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<title>bioRxiv Channel: California Institute of Technology</title>
<link>https://biorxiv.org</link>
<description>
This feed contains articles for bioRxiv Channel "California Institute of Technology"
</description>

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<item rdf:about="https://biorxiv.org/content/10.1101/000091v1?rss=1">
<title>
<![CDATA[
Designing Robustness to Temperature in a Feedforward Loop Circuit 
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</title>
<link>https://biorxiv.org/content/10.1101/000091v1?rss=1</link>
<description><![CDATA[
Incoherent feedforward loops represent important biomolecular circuit elements capable of a rich set of dynamic behavior including adaptation and pulsed responses. Temperature can modulate some of these properties through its effect on the underlying reaction rate parameters. It is generally unclear how to design such a circuit where the properties are robust to variations in temperature. Here, we address this issue using a combination of tools from control and dynamical systems theory as well as preliminary experimental measurements towards such a design. We formalize temperature as an uncertainty acting on system dynamics, exploring both structured and unstructured uncertainty representations. Next, we analyze a standard incoherent feedforward loop circuit, noting mechanisms that intrinsically confer temperature robustness to some of its properties. Further, we explore different negative feedback configurations that can enhance the robustness to temperature. Finally, we find that the response of an incoherent feedforward loop circuit in cells can change with temperature. These results present groundwork for the design of a temperature-robust incoherent feedforward loop circuit.
]]></description>
<dc:creator>Shaunak Sen</dc:creator>
<dc:creator>Jongmin Kim</dc:creator>
<dc:creator>Richard M. Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2013-11-07</dc:date>
<dc:identifier>doi:10.1101/000091</dc:identifier>
<dc:title><![CDATA[Designing Robustness to Temperature in a Feedforward Loop Circuit]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2013-11-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/000448v1?rss=1">
<title>
<![CDATA[
Design and implementation of a synthetic biomolecular concentration tracker 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/000448v1?rss=1</link>
<description><![CDATA[
As a field, synthetic biology strives to engineer increasingly complex artificial systems in living cells. Active feedback in closed loop systems offers a dynamic and adaptive way to ensure constant relative activity independent of intrinsic and extrinsic noise. In this work, we design, model, and implement a biomolecular concentration tracker, in which an output protein tracks the concentration of an input protein. Synthetic modular protein scaffold domains are used to colocalize a two-component system, and a single negative feedback loop modulates the production of the output protein. Using a combination of model and experimental work, we show that the circuit achieves real-time protein concentration tracking in Escherichia coli and that steady state outputs can be tuned.
]]></description>
<dc:creator>Victoria Hsiao</dc:creator>
<dc:creator>Emmanuel LC de los Santos</dc:creator>
<dc:creator>Weston R Whitaker</dc:creator>
<dc:creator>John E Dueber</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2013-11-15</dc:date>
<dc:identifier>doi:10.1101/000448</dc:identifier>
<dc:title><![CDATA[Design and implementation of a synthetic biomolecular concentration tracker]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2013-11-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/000885v1?rss=1">
<title>
<![CDATA[
Resource usage and gene circuit performance characterization in a cell-free ?breadboard? 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/000885v1?rss=1</link>
<description><![CDATA[
The many successes of synthetic biology have come in a manner largely different from those in other engineering disciplines; in particular, without well-characterized and simplified prototyping environments to play a role analogous to wind-tunnels in aerodynamics and breadboards in electrical engineering. However, as the complexity of synthetic circuits increases, the benefits--in cost savings and design cycle time--of a more traditional engineering approach can be significant. We have recently developed an in vitro  breadboard prototyping platform based on E. coli cell extract that allows biocircuits to operate in an environment considerably simpler than but functionally similar to in vivo. The simplicity of this system makes it a promising tool for rapid biocircuit design and testing, as well as for probing fundamental aspects of gene circuit operation normally masked by cellular complexity. In this work we characterize the cell-free breadboard using real-time and simultaneous measurements of transcriptional and translational activities of a small set of reporter genes and a transcriptional activation cascade. We determine the effects of promoter strength, gene concentration, and nucleoside triphosphate concentration on biocircuit properties, and we isolate the specific contributions of essential biomolecular resources--core RNA polymerase and ribosomes--to overall performance. Importantly, we show how limits on resources, particularly those involved in translation, are manifested as reduced expression in the presence of orthogonal genes that serve as additional loads on the system.
]]></description>
<dc:creator>Dan Siegal-Gaskins</dc:creator>
<dc:creator>Zoltan A. Tuza</dc:creator>
<dc:creator>Jongmin Kim</dc:creator>
<dc:creator>Vincent Noireaux</dc:creator>
<dc:creator>Richard M. Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2013-11-25</dc:date>
<dc:identifier>doi:10.1101/000885</dc:identifier>
<dc:title><![CDATA[Resource usage and gene circuit performance characterization in a cell-free ?breadboard?]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2013-11-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/001602v1?rss=1">
<title>
<![CDATA[
p97-dependent retrotranslocation and proteolytic processing govern formation of active Nrf1 upon proteasome inhibition 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/001602v1?rss=1</link>
<description><![CDATA[
Proteasome inhibition elicits an evolutionarily conserved response wherein proteasome subunit mRNAs are upregulated, resulting in recovery of proteasome activity. We previously demonstrated that the transcription factor Nrf1 mediates this homeostatic response in mammalian cells. We show here that Nrf1 is initially translocated into the lumen of the ER, but is rapidly and efficiently retrotranslocated to the cytosolic side of the membrane in a manner that depends on p97/VCP. Normally, retrotranslocated Nrf1 is degraded by the proteasome and active species do not accumulate. However, in cells with compromised proteasomes, retrotranslocated Nrf1 escapes degradation and is cleaved N-terminal to Leu-104 to yield a fragment that is no longer tethered to the ER-membrane. Importantly, this cleavage event is essential for Nrf1-dependent activation of proteasome gene expression upon proteasome inhibition. Our data uncover an unexpected role for p97 in activation of a transcription factor by relocalizing it from the ER lumen to the cytosol.
]]></description>
<dc:creator>Senthil K Radhakrishnan</dc:creator>
<dc:creator>Willem den Besten</dc:creator>
<dc:creator>Raymond J Deshaies</dc:creator>
<dc:creator></dc:creator>
<dc:date>2013-12-29</dc:date>
<dc:identifier>doi:10.1101/001602</dc:identifier>
<dc:title><![CDATA[p97-dependent retrotranslocation and proteolytic processing govern formation of active Nrf1 upon proteasome inhibition]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2013-12-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/002907v1?rss=1">
<title>
<![CDATA[
Population diversification in a yeast metabolic program promotes anticipation of environmental shifts 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/002907v1?rss=1</link>
<description><![CDATA[
Delineating the strategies by which cells contend with combinatorial changing environments is crucial for understanding cellular regulatory organization. When presented with two carbon sources, microorganisms first consume the carbon substrate that supports the highest growth rate (e.g. glucose) and then switch to the secondary carbon source (e.g. galactose), a paradigm known as the Monod model. Sequential sugar utilization has been attributed to transcriptional repression of the secondary metabolic pathway, followed by activation of this pathway upon depletion of the preferred carbon source. In this work, we challenge this notion. Although Saccharomyces cerevisiae cells consume glucose before galactose, we demonstrate that the galactose regulatory pathway is activated in a fraction of the cell population hours before glucose is fully consumed. This early activation reduces the time required for the population to transition between the two metabolic programs and provides a fitness advantage that might be crucial in competitive environments. Importantly, these findings define a new paradigm for the response of microbial populations to combinatorial carbon sources.
]]></description>
<dc:creator>Ophelia S Venturelli</dc:creator>
<dc:creator>Ignacio Zuleta</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator>Hana El-Samad</dc:creator>
<dc:creator></dc:creator>
<dc:date>2014-02-21</dc:date>
<dc:identifier>doi:10.1101/002907</dc:identifier>
<dc:title><![CDATA[Population diversification in a yeast metabolic program promotes anticipation of environmental shifts]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2014-02-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/003335v1?rss=1">
<title>
<![CDATA[
Rapidly characterizing the fast dynamics of RNA genetic circuitry with cell-free transcription-translation (TX-TL) systems 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/003335v1?rss=1</link>
<description><![CDATA[
RNA regulators are emerging as powerful tools to engineer synthetic genetic networks or rewire existing ones. A potential strength of RNA networks is that they may be able to propagate signals on timescales that are set by the fast degradation rates of RNAs. However, a current bottleneck to verifying this potential is the slow design-build-test cycle of evaluating these networks in vivo. Here we adapt an Escherichia coli-based cell-free transcription-translation (TX-TL) system for rapidly prototyping RNA networks. We used this system to measure the response time of an RNA transcription cascade to be approximately five minutes per step of the cascade. We also show that this response time can be adjusted with temperature and regulator threshold response tuning. Finally we use TX-TL to prototype a new RNA network, an RNA single input module, and show that this network temporally stages the expression of two genes in vivo.
]]></description>
<dc:creator>Melissa K Takahashi</dc:creator>
<dc:creator>James Chappell</dc:creator>
<dc:creator>Clarmyra A Hayes</dc:creator>
<dc:creator>Zachary Z Sun</dc:creator>
<dc:creator>Vipul Singhal</dc:creator>
<dc:creator>Kevin J Spring</dc:creator>
<dc:creator>Shaima Al-Khabouri</dc:creator>
<dc:creator>Christopher P Fall</dc:creator>
<dc:creator>Vincent Noireaux</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator>Julius B Lucks</dc:creator>
<dc:creator></dc:creator>
<dc:date>2014-03-17</dc:date>
<dc:identifier>doi:10.1101/003335</dc:identifier>
<dc:title><![CDATA[Rapidly characterizing the fast dynamics of RNA genetic circuitry with cell-free transcription-translation (TX-TL) systems]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2014-03-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/003772v1?rss=1">
<title>
<![CDATA[
Comparison of the theoretical and real-world evolutionary potential of a genetic circuit. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/003772v1?rss=1</link>
<description><![CDATA[
With the development of next-generation sequencing technologies, many large scale experimental efforts aim to map genotypic variability among individuals. This natural variability in populations fuels many fundamental biological processes, ranging from evolutionary adaptation and speciation to the spread of genetic diseases and drug resistance. An interesting and important component of this variability is present within the regulatory regions of genes. As these regions evolve, accumulated mutations lead to modulation of gene expression, which may have consequences for the phenotype. A simple model system where the link between genetic variability, gene regulation and function can be studied in detail is missing. In this article we develop a model to explore how the sequence of the wild-type lac promoter dictates the fold change in gene expression. The model combines single-base pair resolution maps of transcription factor and RNA polymerase binding energies with a comprehensive thermodynamic model of gene regulation. The model was validated by predicting and then measuring the variability of lac operon regulation in a collection of natural isolates. We then implement the model to analyze the sensitivity of the promoter sequence to the regulatory output, and predict the potential for regulation to evolve due to point mutations in the promoter region.
]]></description>
<dc:creator>Manuel Razo-Mejia</dc:creator>
<dc:creator>James Boedicker</dc:creator>
<dc:creator>Daniel Jones</dc:creator>
<dc:creator>Alexander de Luna</dc:creator>
<dc:creator>Justin Block Kinney</dc:creator>
<dc:creator>Rob Phillips</dc:creator>
<dc:creator></dc:creator>
<dc:date>2014-04-02</dc:date>
<dc:identifier>doi:10.1101/003772</dc:identifier>
<dc:title><![CDATA[Comparison of the theoretical and real-world evolutionary potential of a genetic circuit.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2014-04-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/008581v1?rss=1">
<title>
<![CDATA[
An analytical approach to bistable biological circuit discrimination using real algebraic geometry 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/008581v1?rss=1</link>
<description><![CDATA[
Biomolecular circuits with two distinct and stable steady states have been identified as essential components in a wide range of biological networks, with a variety of mechanisms and topologies giving rise to their important bistable property. Understanding the differences between circuit implementations is an important question, particularly for the synthetic biologist faced with determining which bistable circuit design out of many is best for their specific application. In this work we explore the applicability of Sturms theorem--a tool from 19th-century real algebraic geometry--to comparing "functionally equivalent" bistable circuits without the need for numerical simulation. We first consider two genetic toggle variants and two different positive feedback circuits, and show how specific topological properties present in each type of circuit can serve to increase the size of the regions of parameter space in which they function as switches. We then demonstrate that a single competitive monomeric activator added to a purely-monomeric (and otherwise monostable) mutual repressor circuit is sufficient for bistability. Finally, we compare our approach with the Routh-Hurwitz method and derive consistent, yet more powerful, parametric conditions. The predictive power and ease of use of Sturms theorem demonstrated in this work suggests that algebraic geometric techniques may be underutilized in biomolecular circuit analysis.
]]></description>
<dc:creator>Dan Siegal-Gaskins</dc:creator>
<dc:creator>Elisa Franco</dc:creator>
<dc:creator>Tiffany Zhou</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2014-08-30</dc:date>
<dc:identifier>doi:10.1101/008581</dc:identifier>
<dc:title><![CDATA[An analytical approach to bistable biological circuit discrimination using real algebraic geometry]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2014-08-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/008771v1?rss=1">
<title>
<![CDATA[
Synthetic logic circuits using RNA aptamer against T7 RNA polymerase 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/008771v1?rss=1</link>
<description><![CDATA[
Recent advances in nucleic acids engineering introduced several RNA-based regulatory components for synthetic gene circuits, expanding the toolsets to engineer organisms. In this work, we designed genetic circuits implementing an RNA aptamer previously described to have the capability of binding to the T7 RNA polymerase and inhibiting its activity in vitro. Using in vitro transcription assays, we first demonstrated the utility of the RNA aptamer in combination with programmable synthetic transcription networks. As a step to quickly assess the feasibility of aptamer functions in vivo, a cell-free expression system was used as a breadboard to emulate the in vivo conditions of E. coli. We tested the aptamer and its three sequence variants in the cell-free expression system, verifying the aptamer functionality in the cell-free testbed. In vivo expression of aptamer and its variants demonstrated control over GFP expression driven by T7 RNA polymerase with different response curves, indicating its ability to serve as building blocks for both logic circuits and transcriptional cascades. This work elucidates the potential of RNA-based regulators for cell programming with improved controllability leveraging the fast production and degradation time scales of RNA molecules.
]]></description>
<dc:creator>Jongmin Kim</dc:creator>
<dc:creator>Juan F Quijano</dc:creator>
<dc:creator>Enoch Yeung</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2014-09-04</dc:date>
<dc:identifier>doi:10.1101/008771</dc:identifier>
<dc:title><![CDATA[Synthetic logic circuits using RNA aptamer against T7 RNA polymerase]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2014-09-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/015438v1?rss=1">
<title>
<![CDATA[
Engineering Transcriptional Regulator Effector Specificity using Computational Design and In Vitro Rapid Prototyping: Developing a Vanillin Sensor 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/015438v1?rss=1</link>
<description><![CDATA[
The pursuit of circuits and metabolic pathways of increasing complexity and ro-bustness in synthetic biology will require engineering new regulatory tools. Feedback control based on relevant molecules, including toxic intermediates and environmental signals, would enable genetic circuits to react appropriately to changing conditions. In this work, variants of qacR, a tetR family repressor, were generated by computational protein design and screened in a cell-free transcription-translation (TX-TL) system for responsiveness to a new targeted effector. The modified repressors target vanillin, a growth-inhibiting small molecule found in lignocellulosic hydrolysates and other industrial processes. Promising candidates from the in vitro screen were further characterized in vitro and in vivo in a gene circuit. The screen yielded two qacR mutants that respond to vanillin both in vitro and in vivo. We believe this process, a combination of the generation of variants coupled with in vitro screening, can serve as a framework for designing new sensors for other target compounds.
]]></description>
<dc:creator>Emmanuel Lorenzo Cornejo de los Santos</dc:creator>
<dc:creator>Joseph T Meyerowitz</dc:creator>
<dc:creator>Stephen L Mayo</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-02-19</dc:date>
<dc:identifier>doi:10.1101/015438</dc:identifier>
<dc:title><![CDATA[Engineering Transcriptional Regulator Effector Specificity using Computational Design and In Vitro Rapid Prototyping: Developing a Vanillin Sensor]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-02-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/017814v1?rss=1">
<title>
<![CDATA[
Prototyping 1,4-butanediol (BDO) biosynthesis pathway in a cell-free transcription-translation (TX-TL) system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/017814v1?rss=1</link>
<description><![CDATA[
Current methods for assembling metabolic pathways require a process of repeated trial and error and have a long design-build-test cycle. Further, it remains a challenge to precisely tune enzyme expression levels for maximizing target metabolite production. Recently it was shown that a cell-free transcriptional-translation system (TX-TL) can be used to rapidly prototype novel complex biocircuits as well as metabolic pathways. TX-TL systems allow protein expression from multiple DNA pieces, opening up the possibility of modulating concentrations of DNA encoding individual pathway enzymes and testing the related effect on metabolite production. In this work, we demonstrate TX-TL as a platform for exploring the design space of metabolic pathways using a 1,4-BDO biosynthesis pathway as an example. Using TX-TL, we verified enzyme expression and enzyme activity and identified the conversion of 4-hydroxybutyrate to downstream metabolites as a limiting step of the 1,4-BDO pathway. We further tested combinations of various enzyme expression levels and found increasing downstream enzyme expression levels improved 1,4-BDO production.
]]></description>
<dc:creator>Yong Y Wu</dc:creator>
<dc:creator>Stephanie Culler</dc:creator>
<dc:creator>Julia Khandurina</dc:creator>
<dc:creator>Stephen Van Dien</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-04-09</dc:date>
<dc:identifier>doi:10.1101/017814</dc:identifier>
<dc:title><![CDATA[Prototyping 1,4-butanediol (BDO) biosynthesis pathway in a cell-free transcription-translation (TX-TL) system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-04-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/019620v1?rss=1">
<title>
<![CDATA[
Characterizing and Prototyping Genetic Networks with Cell-Free Transcription-Translation Reactions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/019620v1?rss=1</link>
<description><![CDATA[
A central goal of synthetic biology is to engineer cellular behavior by engineering synthetic gene networks for a variety of biotechnology and medical applications. The process of engineering gene networks often involves an iterative  design-build-test cycle, whereby the parts and connections that make up the network are built, characterized and varied until the desired network function is reached. Many advances have been made in the design and build portions of this cycle. However, the slow process of in vivo characterization of network function often limits the timescale of the testing step. Cell-free transcription-translation (TX-TL) systems offer a simple and fast alternative to performing these characterizations in cells. Here we provide an overview of a cell-free TX-TL system that utilizes the native Escherichia coli TX-TL machinery, thereby allowing a large repertoire of parts and networks to be characterized. As a way to demonstrate the utility of cell-free TX-TL, we illustrate the characterization of two genetic networks: an RNA transcriptional cascade and a protein regulated incoherent feed-forward loop. We also provide guidelines for designing TX-TL experiments to characterize new genetic networks. We end with a discussion of current and emerging applications of cell free systems.nnAbbreviations
]]></description>
<dc:creator>Melissa K Takahashi</dc:creator>
<dc:creator>Clarmyra A. Hayes</dc:creator>
<dc:creator>James Chappell</dc:creator>
<dc:creator>Zachary Z. Sun</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator>Vincent Noireaux</dc:creator>
<dc:creator>Julius B. Lucks</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-05-21</dc:date>
<dc:identifier>doi:10.1101/019620</dc:identifier>
<dc:title><![CDATA[Characterizing and Prototyping Genetic Networks with Cell-Free Transcription-Translation Reactions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-05-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/019695v1?rss=1">
<title>
<![CDATA[
Protein degradation in a TX-TL cell-free expression system using ClpXP protease 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/019695v1?rss=1</link>
<description><![CDATA[
Introduction Introduction RESULTS AND DISCUSSION CONCLUSION ACKNOWLEDGEMENTS MATERIALS AND METHODS REFERENCES An in vitro S30-based Escherichia coli expression system ("Transcription-Translation", or "TX-TL") has been developed as an alternative prototyping environment to the cell for synthetic circuits [1-5]. Basic circuit elements, such as switches and cascades, have been shown to function in TX-TL, as well as bacteriophage assembly [2, 6]. Circuits can also be prototyped from basic parts within 8 hours, avoiding cloning and transformation steps [7]. However, most published results have been obtained in a "batch mode" reaction, where factors that play an important role for in vivo circuit dynamics ...
]]></description>
<dc:creator>Zachary Sun</dc:creator>
<dc:creator>Jongmin Kim</dc:creator>
<dc:creator>Vipul Singhal</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-05-22</dc:date>
<dc:identifier>doi:10.1101/019695</dc:identifier>
<dc:title><![CDATA[Protein degradation in a TX-TL cell-free expression system using ClpXP protease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-05-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/027656v1?rss=1">
<title>
<![CDATA[
Design Space Exploration of the Violacein Pathway in Escherichia coli Based Transcription Translation Cell-Free System (TX-TL) 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/027656v1?rss=1</link>
<description><![CDATA[
In this study, an Escherichia coli (E. coli) based transcription translation cell-free system (TX-TL) was employed to sample various enzyme expression levels of the violacein pathway. The pathway was successfully reconstructed in TX-TL. Its variation produced different metabolites as evident from the extracts assorted colors. Analysis of the violacein product via UV-Vis absorption and liquid chromatography-mass spectrometry (LC-MS) detected 68 ng of violacein per l reaction volume. Significant buildup of prodeoxyviolacein intermediate was also detected in the equimolar TX-TL reaction. Finally, design space exploration experiments suggested an improvement in violacein production at high VioC and VioD DNA concentrations.
]]></description>
<dc:creator>Phuc H.B. Nguyen</dc:creator>
<dc:creator>Yong Wu</dc:creator>
<dc:creator>Shaobin Guo</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-09-27</dc:date>
<dc:identifier>doi:10.1101/027656</dc:identifier>
<dc:title><![CDATA[Design Space Exploration of the Violacein Pathway in Escherichia coli Based Transcription Translation Cell-Free System (TX-TL)]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-09-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/029819v1?rss=1">
<title>
<![CDATA[
Generalized Regressive Motion: a Visual Cue to Collision 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/029819v1?rss=1</link>
<description><![CDATA[
Brains and sensory systems evolved to guide motion. Central to this task is controlling the approach to stationary obstacles and detecting moving organisms. Looming has been proposed as the main monocular visual cue for detecting the approach of other animals and avoiding collisions with stationary obstacles. Elegant neural mechanisms for looming detection have been found in the brain of insects and vertebrates. However, looming has not been analyzed in the context of collisions between two moving animals. We propose an alternative strategy, generalized regressive motion (GRM), which is consistent with recently observed behavior in fruit flies. Geometric analysis proves that GRM is a reliable cue to collision among conspecifics, whereas agent-based modeling suggests that GRM is a better cue than looming as a means to detect approach, prevent collisions and maintain mobility.
]]></description>
<dc:creator>Krzysztof Chalupka</dc:creator>
<dc:creator>Michael Dickinson</dc:creator>
<dc:creator>Pietro Perona</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-10-26</dc:date>
<dc:identifier>doi:10.1101/029819</dc:identifier>
<dc:title><![CDATA[Generalized Regressive Motion: a Visual Cue to Collision]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-10-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/029967v1?rss=1">
<title>
<![CDATA[
A population-based temporal logic gate for timing and recording chemical events 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/029967v1?rss=1</link>
<description><![CDATA[
Single-cell bacterial sensors have numerous applications in human health monitoring, environmental chemical detection, and materials biosynthesis. Such bacterial devices need not only the capability to differentiate between combinations of inputs, but also the ability to process signal timing and duration. In this work, we present a two-input temporal logic gate that can sense and record the order of the inputs, the timing between inputs, and the duration of input pulses. The temporal logic gate design relies on unidirectional DNA recombination with bacteriophage integrases to detect and encode sequences of input events. When implemented in a chromosomally-modified E. coli strain, we can utilize stochastic single cell responses to predict overall heterogeneous population behavior. We show that a stochastic model can be used to predict final population distributions of this E. coli strain, and thus that final differentiated sub-populations can be used to deduce the timing and duration of transient chemical events.
]]></description>
<dc:creator>Victoria Hsiao</dc:creator>
<dc:creator>Yutaka Hori</dc:creator>
<dc:creator>Paul Rothemund</dc:creator>
<dc:creator>Richard Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-10-27</dc:date>
<dc:identifier>doi:10.1101/029967</dc:identifier>
<dc:title><![CDATA[A population-based temporal logic gate for timing and recording chemical events]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-10-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/031658v1?rss=1">
<title>
<![CDATA[
DataJoint: managing big scientific data using MATLAB or Python 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/031658v1?rss=1</link>
<description><![CDATA[
The rise of big data in modern research poses serious challenges for data management: Large and intricate datasets from diverse instrumentation must be precisely aligned, annotated, and processed in a variety of ways to extract new insights. While high levels of data integrity are expected, research teams have diverse backgrounds, are geographically dispersed, and rarely possess a primary interest in data science. Here we describe DataJoint, an open-source toolbox designed for manipulating and processing scientific data under the relational data model. Designed for scientists who need a flexible and expressive database language with few basic concepts and operations, DataJoint facilitates multiuser access, efficient queries, and distributed computing. With implementations in both MATLAB and Python, DataJoint is not limited to particular file formats, acquisition systems, or data modalities and can be quickly adapted to new experimental designs. DataJoint and related resources are available at http://datajoint.github.com.
]]></description>
<dc:creator>Dimitri Yatsenko</dc:creator>
<dc:creator>Jacob Reimer</dc:creator>
<dc:creator>Alexander S Ecker</dc:creator>
<dc:creator>Edgar Y Walker</dc:creator>
<dc:creator>Fabian Sinz</dc:creator>
<dc:creator>Philipp Berens</dc:creator>
<dc:creator>Andreas Hoenselaar</dc:creator>
<dc:creator>Ronald James Cotton</dc:creator>
<dc:creator>Athanassios S. Siapas</dc:creator>
<dc:creator>Andreas S. Tolias</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-11-14</dc:date>
<dc:identifier>doi:10.1101/031658</dc:identifier>
<dc:title><![CDATA[DataJoint: managing big scientific data using MATLAB or Python]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-11-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/037234v1?rss=1">
<title>
<![CDATA[
Intracranial Markers of Conscious Face Perception in Humans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/037234v1?rss=1</link>
<description><![CDATA[
The comparison between perceived and unperceived trials at perceptual threshold isolates not only the core neuronal substrate of a particular conscious perception, but also aspects of brain activity that facilitate, hinder or tend to follow conscious perception. We take a step towards the resolution of these confounds by combining an analysis of ECoG neuronal responses observed during the presentation of faces partially masked by Continuous Flash Suppression, and those responses observed during the unmasked presentation of faces and other images in the same subjects. Neuronal activity in both the fusiform gyrus and the superior temporal sulcus discriminated seen vs. unseen faces in the masked paradigm and upright faces vs. other categories in the unmasked paradigm. However, only the former discriminated upright vs. inverted faces in the unmasked paradigm. Our results suggest a prominent role for the fusiform gyrus in the configural perception of faces.
]]></description>
<dc:creator>Fabiano Baroni</dc:creator>
<dc:creator>Jochem van Kempen</dc:creator>
<dc:creator>Hiroto Kawasaki</dc:creator>
<dc:creator>Christopher K. Kovach</dc:creator>
<dc:creator>Hiroyuki Oya</dc:creator>
<dc:creator>Matthew A. Howard</dc:creator>
<dc:creator>Ralph Adolphs</dc:creator>
<dc:creator>Naotsugu Tsuchiya</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-02-01</dc:date>
<dc:identifier>doi:10.1101/037234</dc:identifier>
<dc:title><![CDATA[Intracranial Markers of Conscious Face Perception in Humans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-02-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/037515v1?rss=1">
<title>
<![CDATA[
A Genetically Encoded Reporter for Diffusion Weighted Magnetic Resonance Imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/037515v1?rss=1</link>
<description><![CDATA[
The ability to monitor gene expression in intact, optically opaque animals is important for a multitude of applications including longitudinal imaging of transgene expression and long term tracking of cell based therapeutics. Magnetic resonance imaging (MRI) could enable such monitoring with high spatial and temporal resolution. However, existing MRI reporter genes, based primarily on metal-binding proteins or chemical exchange saturation transfer probes, are limited by their reliance on metal ions or relatively low sensitivity. In this work, we introduce a new class of genetically encoded reporters for MRI that work by altering water diffusivity. We show that overexpression of the human water channel aquaporin 1 (AQP1) produces robust contrast in diffusion weighted MRI by increasing effective water diffusivity in tissues by over 100% without affecting cell viability or morphology. Low levels of AQP1 expression ({small tilde}1 M), or mixed populations comprising as few as 10% AQP1-expressing cells, produce sufficient contrast to be observed by MRI. We demonstrate the utility of AQP1 in vivo by imaging gene expression in intracranial tumor xenografts. Overall, our results establish AQP1 as a new, metal-free, nontoxic and sensitive genetically encoded reporter for diffusion weighted MRI.
]]></description>
<dc:creator>Arnab Mukherjee</dc:creator>
<dc:creator>Di Wu</dc:creator>
<dc:creator>Hunter C. Davis</dc:creator>
<dc:creator>Mikhail G. Shapiro</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-01-25</dc:date>
<dc:identifier>doi:10.1101/037515</dc:identifier>
<dc:title><![CDATA[A Genetically Encoded Reporter for Diffusion Weighted Magnetic Resonance Imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-01-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/039032v1?rss=1">
<title>
<![CDATA[
Contents of Consciousness Investigated as Integrated Information in Direct Human Brain Recordings 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/039032v1?rss=1</link>
<description><![CDATA[
Integrated information theory postulates that the particular way stimuli appear when we consciously experience them arises from integrated information relationships across neural populations. We investigated if such equivalence holds by testing if similar/different percepts map onto similar/different information structures. We computed integrated information structure from intracranial EEGs recorded in 6 neurosurgical patients who had electrodes implanted over posterior cortices. During recording, we dissociated subjective percepts from physical inputs in three distinct stimulus paradigms (passive viewing, continuous flash suppression, and backward masking). Unsupervised classification showed that integrated information within stimulus-selective cortical regions classified visual experiences with significant accuracy (peaking on average around 64% classification accuracy). Classification by other relevant information theoretic measures such as mutual information and entropy was consistently poorer (56% and 54% accuracy). The findings argue that concepts from integrated information theory are empirically testable, promising a potential link between conscious experience and informational structures.
]]></description>
<dc:creator>Andrew M. Haun</dc:creator>
<dc:creator>Masafumi Oizumi</dc:creator>
<dc:creator>Christopher K Kovach</dc:creator>
<dc:creator>Hiroto Kawasaki</dc:creator>
<dc:creator>Hiroyuki Oya</dc:creator>
<dc:creator>Matthew A Howard</dc:creator>
<dc:creator>Ralph Adolphs</dc:creator>
<dc:creator>Naotsugu Tsuchiya</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-02-15</dc:date>
<dc:identifier>doi:10.1101/039032</dc:identifier>
<dc:title><![CDATA[Contents of Consciousness Investigated as Integrated Information in Direct Human Brain Recordings]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-02-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/040741v1?rss=1">
<title>
<![CDATA[
Coarse-grained simulation reveals key features of HIV-1 capsid self-assembly 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/040741v1?rss=1</link>
<description><![CDATA[
AbstractThe maturation of HIV-1 viral particles is essential for viral infectivity. During maturation, many copies of the capsid protein (CA) self-assemble into a capsid shell to enclose the viral RNA. The mechanistic details of the initiation and early stages of capsid assembly remain to be delineated. We present coarse-grained simulations of capsid assembly under various conditions, considering not only capsid lattice self-assembly but also the potential disassembly of capsid upon delivery to the cytoplasm of a target cell. The effects of CA concentration, molecular crowding, and the conformational variability of CA are described, with results indicating that capsid nucleation and growth is a multi-stage process requiring well-defined metastable intermediates. Generation of the mature capsid lattice is sensitive to local conditions, with relatively subtle changes in CA concentration and molecular crowding influencing self-assembly and the ensemble of structural morphologies.
]]></description>
<dc:creator>John M A Grime</dc:creator>
<dc:creator>James F Dama</dc:creator>
<dc:creator>Barbie K Ganser-Pornillos</dc:creator>
<dc:creator>Cora L Woodward</dc:creator>
<dc:creator>Grant J Jensen</dc:creator>
<dc:creator>Mark J Yeager</dc:creator>
<dc:creator>Gregory Voth</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-02-23</dc:date>
<dc:identifier>doi:10.1101/040741</dc:identifier>
<dc:title><![CDATA[Coarse-grained simulation reveals key features of HIV-1 capsid self-assembly]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-02-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/041624v1?rss=1">
<title>
<![CDATA[
Sporulation, bacterial cell envelopes, and the origin of life 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/041624v1?rss=1</link>
<description><![CDATA[
Four recent papers from our group exploiting the power of electron cryotomography to produce 3-D reconstructions of intact cells in a near-native state have led to the proposal that an ancient sporulation-like event gave rise to the second membrane in diderm bacteria. Here we review the images of sporulating monoderm and diderm cells which show how sporulation leads to diderm cells. We also review the images of Gram-negative and Gram-positive cell walls that show they are more closely related than previously thought, and explain how this provides critical support for the hypothesis. Mapping the distribution of cell envelope architectures onto the most recent phylogenetic tree of life then leads to the conclusion that the diderm cell plan, and therefore the sporulation-like event that gave rise to it, must be very ancient. One explanation for the biogeologic record is that during the cataclysmic transitions of early Earth, cellular evolution may have gone through a bottleneck where only spores survived (LUCA was a spore).
]]></description>
<dc:creator>Elitza I Tocheva</dc:creator>
<dc:creator>Davi R Ortega</dc:creator>
<dc:creator>Grant J Jensen</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-02-29</dc:date>
<dc:identifier>doi:10.1101/041624</dc:identifier>
<dc:title><![CDATA[Sporulation, bacterial cell envelopes, and the origin of life]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-02-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/041632v1?rss=1">
<title>
<![CDATA[
Rational design and whole-genome predictions of single guide RNAs for efficient CRISPR/Cas9-mediated genome editing in Ciona 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/041632v1?rss=1</link>
<description><![CDATA[
The CRISPR/Cas9 system has emerged as an important tool for various genome engineering applications. A current obstacle to high throughput applications of CRISPR/Cas9 is the imprecise prediction of highly active single guide. RNAs (sgRNAs). We previously implemented the CRISPR/Cas9 system to induce tissue-specific mutations in the tunicate Ciona. In the present study, we designed and tested 83 single guide RNA (sgRNA) vectors targeting 23 genes expressed in the cardiopharyngeal progenitors and surrounding tissues of Ciona embryo. Using high-throughput sequencing of mutagenized alleles, we identified guide sequences that correlate with sgRNA mutagenesis activity and used this information for the rational design of all possible sgRNAs targeting the Ciona transcriptome. We also describe a one-step cloning-free protocol for the assembly of sgRNA expression cassettes. These cassettes can be directly electroporated as unpurified PCR products into Ciona embryos for sgRNA expression in vivo, resulting in high frequency of CRISPR/Cas9-mediated mutagenesis in somatic cells of electroporated embryos.nnWe found a strong correlation between the frequency of an Ebf loss-of-function phenotype and the mutagenesis efficacies of individual Ebf-targeting sgRNAs tested using this method. We anticipate that our approach can be scaled up to systematically design and deliver highly efficient sgRNAs for the tissue-specific investigation of gene functions in Ciona.
]]></description>
<dc:creator>Shashank Gandhi</dc:creator>
<dc:creator>Lionel Christiaen</dc:creator>
<dc:creator>Alberto Stolfi</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-02-28</dc:date>
<dc:identifier>doi:10.1101/041632</dc:identifier>
<dc:title><![CDATA[Rational design and whole-genome predictions of single guide RNAs for efficient CRISPR/Cas9-mediated genome editing in Ciona]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-02-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/044149v1?rss=1">
<title>
<![CDATA[
Divergence of gene regulatory network linkages during specification of ectoderm and mesoderm in early development of sea urchins 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/044149v1?rss=1</link>
<description><![CDATA[
Developmental gene regulatory networks (dGRNs) are assemblages of interacting regulatory factors that direct ontogeny of animal body plans. The hierarchical topology of these networks predicts that their nodes will evolve at different rates and consequently will bias the trajectories of embryonic evolution. To test this, detailed, comparative analyses of dGRNs that specify early, global embryonic domains are required. The most extensively detailed dGRNs have been documented for one of the two subclasses of extant sea urchins, the euechinoids. Remarkably, euechinoid dGRNs operating in early development show little appreciable change even though they diverged approximately 90 million years ago (mya). Therefore, to better understand the evolutionary dynamics of dGRNs, comparative microdissection must be undertaken for sea urchins that diverged deeper in geological time. Recent studies of cidaroids, the sister clade of euechinoid sea urchins, suggest that comparative analyses of their embryonic domain specification may prove insightful for understanding the evolutionary dynamics of dGRNs. Here, I report the spatiotemporal dynamics of 19 regulatory factors involved in dorsal-ventral patterning of non-skeletogenic mesodermal and ectodermal domains in the early development of Eucidaris tribuloides, a cidaroid sea urchin. Multiple lines of evidence indicate that deployment of ectodermal regulatory factors is more impervious to change than mesodermal regulatory factors in the sea urchin lineage and are supported by multiple lines of experimental evidence. Additionally, endogenous spatiotemporal expression data, intra-class reporter microinjections, and perturbation analyses of Nodal and Notch signaling allow the enumeration of numerous alterations to regulatory factor deployment since the divergence of echinoids. These results provide a global view of early embryonic developmental processes in two clades that diverged at least 268.8 mya and show that the dGRNs controlling embryonic specification exhibit differential lability, supporting the hypothesis that the topologies of dGRNs bias rates of evolutionary change and alter the developmental evolutionary trajectories of embryogenesis.nnAuthor SummaryEarly in the development of an embryo, networks of genes are initiated to differentiate the rapidly dividing cells into distinct territories that will later serve specific functions. Sea urchins have revealed much about how this process unfolds. Recent studies have focused on one of the two modern lineages of sea urchins and have shown that these processes have not appreciably changed over the past 90 million years. I sought to determine if this trend extends over even larger evolutionary distances by investigating similar processes in a sea urchin from the second modern lineage, which is removed by 268 million years of evolution. By revealing where and when these genes are expressed and interfering with common mechanisms of development in a distantly related sea urchin, I show that changes to these networks of genes have occurred at all levels of the network. Additionally, I present data that suggests that changes to these networks of genes occur disproportionately in certain embryonic territories, which may be true for early development for other groups of organisms as well.
]]></description>
<dc:creator>Eric M Erkenbrack</dc:creator>
<dc:creator>Eric H Davidson</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-03-16</dc:date>
<dc:identifier>doi:10.1101/044149</dc:identifier>
<dc:title><![CDATA[Divergence of gene regulatory network linkages during specification of ectoderm and mesoderm in early development of sea urchins]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-03-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/045435v1?rss=1">
<title>
<![CDATA[
Modeling multi-particle complexes in stochastic chemical systems 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/045435v1?rss=1</link>
<description><![CDATA[
Large complexes of classical particles play central roles in biology, in polymer physics, and in other disciplines. However, physics currently lacks mathematical methods for describing such complexes in terms of component particles, interaction energies, and assembly rules. Here we describe a Fock space structure that addresses this need, as well as diagrammatic methods that facilitate the use of this formalism. These methods can dramatically simplify the equations governing both equilibrium and non-equilibrium stochastic chemical systems. A mathematical relationship between the set of all complexes and a list of rules for complex assembly is also identified.
]]></description>
<dc:creator>Muir J Morrison</dc:creator>
<dc:creator>Justin B Kinney</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-03-23</dc:date>
<dc:identifier>doi:10.1101/045435</dc:identifier>
<dc:title><![CDATA[Modeling multi-particle complexes in stochastic chemical systems]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-03-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/046813v1?rss=1">
<title>
<![CDATA[
A new computational model captures fundamental architectural features of diverse biological networks 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/046813v1?rss=1</link>
<description><![CDATA[
Complex biological systems are often represented by network graphs; however, their structural features are not adequately captured by existing computational graph models, perhaps because the datasets used to assemble them are incomplete and contain elements that lack shared functions. Here, we analyze three large, near-complete networks that produce specific cellular or behavioral outputs: a molecular yeast mitochondrial regulatory protein network, and two anatomical networks of very different scale, the mouse brain mesoscale connectivity network, and the C. elegans neuronal network. Surprisingly, these networks share similar characteristics. All consist of large communities composed of modules with general functions, and topologically distinct subnetworks spanning modular boundaries responsible for their more specific phenotypical outputs. We created a new model, SBM-PS, which generates networks by combining communities, followed by adjustment of connections by a  path selection mechanism. This model captures fundamental architectural features that are common to the three networks.
]]></description>
<dc:creator>Bader Al-Anzi</dc:creator>
<dc:creator>Noah Olsman</dc:creator>
<dc:creator>Christopher Ormerod</dc:creator>
<dc:creator>Sherif Gerges</dc:creator>
<dc:creator>Georgios Piliouras</dc:creator>
<dc:creator>John Ormerod</dc:creator>
<dc:creator>Kai Zinn</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-04-02</dc:date>
<dc:identifier>doi:10.1101/046813</dc:identifier>
<dc:title><![CDATA[A new computational model captures fundamental architectural features of diverse biological networks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-04-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/050948v1?rss=1">
<title>
<![CDATA[
Neighborhood regulation by lncRNA promoters, transcription, and splicing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/050948v1?rss=1</link>
<description><![CDATA[
Mammalian genomes are pervasively transcribed to produce thousands of spliced long noncoding RNAs (lncRNAs), whose functions remain poorly understood. Because recent evidence has implicated several specific lncRNA loci in the local regulation of gene expression, we sought to determine whether such local regulation is a property of many lncRNA loci. We used genetic manipulations to dissect 12 genomic loci that produce lncRNAs and found that 5 of these loci influence the expression of a neighboring gene in cis. Surprisingly, however, none of these effects required the specific lncRNA transcripts themselves and instead involved general processes associated with their production, including enhancer-like activity of gene promoters, the process of transcription, and the splicing of the transcript. Interestingly, such effects are not limited to lncRNA loci: we found similar effects on local gene expression at 4 of 6 protein-coding loci. These results demonstrate that  crosstalk among neighboring genes is a prevalent phenomenon that can involve multiple mechanisms and cis regulatory signals, including a novel role for RNA splicing. These mechanisms may explain the function and evolution of some genomic loci that produce lncRNAs.
]]></description>
<dc:creator>Jesse M Engreitz</dc:creator>
<dc:creator>Jenna E Haines</dc:creator>
<dc:creator>Glen Munson</dc:creator>
<dc:creator>Jenny Chen</dc:creator>
<dc:creator>Elizabeth M Perez</dc:creator>
<dc:creator>Michael Kane</dc:creator>
<dc:creator>Patrick E McDonel</dc:creator>
<dc:creator>Mitchell Guttman</dc:creator>
<dc:creator>Eric S Lander</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-04-29</dc:date>
<dc:identifier>doi:10.1101/050948</dc:identifier>
<dc:title><![CDATA[Neighborhood regulation by lncRNA promoters, transcription, and splicing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-04-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/054676v1?rss=1">
<title>
<![CDATA[
MPAthic: quantitative modeling of sequence-function relationships for massively parallel assays 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/054676v1?rss=1</link>
<description><![CDATA[
Massively parallel assays (MPAs) are being rapidly adopted for studying a wide range of DNA, RNA, and protein sequence-function relationships. However, the software available for quantitatively modeling these relationships is severely limited. Here we describe MPAthic, a software package that enables the rapid inference of such models from a variety of MPA datasets. Using both simulated and previously published data, we show that the modeling capabilities of MPAthic greatly improve on those of existing software. In particular, only MPAthic can accurately quantify the strength of epistatic interactions. These capabilities address a major need in the analysis of MPA data.
]]></description>
<dc:creator>William T. Ireland</dc:creator>
<dc:creator>Justin B. Kinney</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-05-21</dc:date>
<dc:identifier>doi:10.1101/054676</dc:identifier>
<dc:title><![CDATA[MPAthic: quantitative modeling of sequence-function relationships for massively parallel assays]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-05-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/056564v1?rss=1">
<title>
<![CDATA[
iSUMO - integrative prediction of functionally relevant SUMOylated proteins 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/056564v1?rss=1</link>
<description><![CDATA[
Post-translational modifications by the Small Ubiquitin-like Modifier (SUMO) are essential for diverse cellular functions. Large-scale experiment and sequence-based predictions have identified thousands of SUMOylated proteins. However, the overlap between the datasets is small, suggesting many false positives with low functional relevance. Therefore, we integrated ~800 sequence features and protein characteristics such as cellular function and protein-protein interactions in a machine learning approach to score likely functional SUMOylation events (iSUMO). iSUMO is trained on a total of 24 large-scale datasets, and it predicts 2,291 and 706 SUMO targets in human and yeast, respectively. These estimates are five times higher than what existing sequence-based tools predict at the same 5% false positive rate. Protein-protein and protein-nucleic acid interactions are highly predictive of protein SUMOylation, supporting a role of the modification in protein complex formation. We note the marked prevalence of SUMOylation amongst RNA-binding proteins. We validate iSUMO predictions by experimental or other evidence. iSUMO therefore represents a comprehensive tool to identify high-confidence, functional SUMOylation events for human and yeast.
]]></description>
<dc:creator>Xiaotong Yao</dc:creator>
<dc:creator>Rebecca Bish</dc:creator>
<dc:creator>Christine Vogel</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-06-01</dc:date>
<dc:identifier>doi:10.1101/056564</dc:identifier>
<dc:title><![CDATA[iSUMO - integrative prediction of functionally relevant SUMOylated proteins]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-06-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/058016v1?rss=1">
<title>
<![CDATA[
Binding of synGAP to PDZ Domains of PSD-95 is Regulated by Phosphorylation and Shapes the Composition of the Postsynaptic Density 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/058016v1?rss=1</link>
<description><![CDATA[
SynGAP is a Ras/Rap GTPase-activating protein (GAP) present in high concentration in postsynaptic densities (PSDs) from mammalian forebrain where it binds to all three PDZ (PSD-95, Discs-large, ZO-1) domains of PSD-95. We show that phosphorylation of synGAP by Ca2+/calmodulin-dependent protein kinase II (CaMKII) decreases its affinity for the PDZ domains as much as 10-fold, measured by surface plasmon resonance. SynGAP is abundant enough in postsynaptic densities (PSDs) to occupy about one third of the PDZ domains of PSD-95. Therefore, we hypothesize that phosphorylation by CaMKII reduces synGAP's ability to restrict binding of other proteins to the PDZ domains of PSD-95. We support this hypothesis by showing that three critical postsynaptic signaling proteins that bind to the PDZ domains of PSD-95 are present at a higher ratio to PSD-95 in PSDs isolated from synGAP heterozygous mice.
]]></description>
<dc:creator>Ward G Walkup</dc:creator>
<dc:creator>Tara L Mastro</dc:creator>
<dc:creator>Leslie T Schenker</dc:creator>
<dc:creator>Jost Vielmetter</dc:creator>
<dc:creator>Rebecca Hu</dc:creator>
<dc:creator>Ariella Iancu</dc:creator>
<dc:creator>Meera Reghunathan</dc:creator>
<dc:creator>Barry D Bannon</dc:creator>
<dc:creator>Mary B Kennedy</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-06-09</dc:date>
<dc:identifier>doi:10.1101/058016</dc:identifier>
<dc:title><![CDATA[Binding of synGAP to PDZ Domains of PSD-95 is Regulated by Phosphorylation and Shapes the Composition of the Postsynaptic Density]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-06-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/059675v1?rss=1">
<title>
<![CDATA[
The role of single occupancy effects on integrase dynamics in a cell-free system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/059675v1?rss=1</link>
<description><![CDATA[
Phage integrase-based circuits are an alternative approach to relying on transcriptional and translational repression for biomolecular circuits. Previous research has shown that circuits based on integrases can perform a variety of functions, including counters, Boolean logic operators, memory modules and temporal event detectors. It is therefore essential to develop a principled theoretical and experimental framework for the design, implementation and study of such circuits. One of the fundamental questions that such a framework should address concerns the functionality limitations and temporal dynamics of the integrases as regulatory elements. Here, we test the functionality of several large serine integrases from a recently published library in a cell-free transcription-translation (TX-TL) platform. Additionally, we use a combination of experimental data and models to investigate integrase dynamics as a function of enzyme concentration and number of binding sites.nnWe report that sequestration of integrase molecules, either in the form of monomers or dimers, by the integrase's own binding sites dominates integrase dynamics, and that the delay in the activation of the reporter is negatively correlated with integrase plasmid concentration. We have validated our sequestration hypothesis by building a model with MATLABs SimBiology toolbox, and running simulations with various integrase and binding sites concentrations. The simulation results qualitatively match the experimental results, and offer further insights into the system.
]]></description>
<dc:creator>Georgios Artavanis</dc:creator>
<dc:creator>Victoria Hsiao</dc:creator>
<dc:creator>Clarmyra A Hayes</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-06-18</dc:date>
<dc:identifier>doi:10.1101/059675</dc:identifier>
<dc:title><![CDATA[The role of single occupancy effects on integrase dynamics in a cell-free system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-06-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/061218v1?rss=1">
<title>
<![CDATA[
Enhancer sharing promotes neighborhoods of transcriptional regulation across eukaryotes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/061218v1?rss=1</link>
<description><![CDATA[
Enhancers physically interact with transcriptional promoters, looping over distances that can span multiple regulatory elements. Given that enhancer-promoter (EP) interactions generally occur via common protein complexes, it is unclear whether EP pairing is predominantly deterministic or proximity guided. Here we present cross-organismic evidence suggesting that most EP pairs are compatible, largely determined by physical proximity rather than specific interactions. By re-analyzing transcriptome datasets, we find that the transcription of gene neighbors is correlated over distances that scale with genome size. We experimentally show that non-specific EP interactions can explain such correlation, and that EP distance acts as a scaling factor for the transcriptional influence of an enhancer. We propose that enhancer sharing is commonplace among eukaryotes, and that EP distance is an important layer of information in gene regulation.
]]></description>
<dc:creator>Porfirio Quintero-Cadena</dc:creator>
<dc:creator>Paul Sternberg</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-06-28</dc:date>
<dc:identifier>doi:10.1101/061218</dc:identifier>
<dc:title><![CDATA[Enhancer sharing promotes neighborhoods of transcriptional regulation across eukaryotes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-06-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/067892v1?rss=1">
<title>
<![CDATA[
Low activity microstates during sleep 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/067892v1?rss=1</link>
<description><![CDATA[
A better understanding of sleep requires evaluating the distinct activity patterns of the brain during sleep. We performed extracellular recordings of large populations of hippocampal region CA1 neurons in freely moving rats across sleep and waking states. Throughout non-REM (non-rapid eye movement) sleep, we observed periods of diminished oscillatory and population spiking activity lasting on the order of seconds, which we refer to as "LOW" activity sleep states. LOW states featured enhanced firing in a subset of "LOW-active" cells, and greater firing in putative interneurons compared to DOWN/OFF states. LOW activity sleep was preceded and followed by increased sharp-wave ripple (SWR) activity. We also observed decreased slow-wave activity (SWA) and sleep spindles in the hippocampus local-field potential (LFP) and neocortical electroencephalogram (EEG) upon LOW onset, but only a partial rebound immediately after LOW. LOW states demonstrated LFP, EEG, and EMG patterns consistent with sleep, but frequently transitioned into microarousals (MAs) and showed EMG and LFP spectral differences from previously described small-amplitude irregular activity (SIA) during quiet waking. Their likelihood increased over the course of sleep, particularly following REM sleep. To confirm that LOW is a brain-wide phenomenon, we analyzed data from the entorhinal cortex of rats, medial prefrontal cortex, and anterior thalamus of mice, obtained from crcns.org and found that LOW states corresponded to markedly diminished activity simultaneously in all of these regions. We propose that LOW states are an important microstate within non-REM sleep that provide respite from high-activity sleep, and may serve a restorative function.
]]></description>
<dc:creator>Hiroyuki Miyawaki</dc:creator>
<dc:creator>Yazan Billeh</dc:creator>
<dc:creator>Kamran Diba</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-08-04</dc:date>
<dc:identifier>doi:10.1101/067892</dc:identifier>
<dc:title><![CDATA[Low activity microstates during sleep]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-08-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/083329v1?rss=1">
<title>
<![CDATA[
The Effect of Compositional Context on Synthetic Gene Net-works 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/083329v1?rss=1</link>
<description><![CDATA[
It is well known that synthetic gene expression is highly sensitive to how comprising genetic elements (promoter structure, spacing regions between promoter and coding sequences, ribosome binding sites, etc.) are spatially configured. An important topic that has received far less attention is how the physical layout of entire genes within a synthetic gene network affects their individual expression levels. In this paper we show, both quantitatively and qualitatively, that compositional context can significantly alter expression levels in synthetic gene networks. We also show that these compositional context effects are pervasive both at the transcriptional and translational level. Further, we demonstrate that key characteristics of gene induction, such as ultra-sensitivity and dynamic range, are heavily dependent on compositional context. We postulate that supercoiling can be used to explain these interference effects and validate this hypothesis through modeling and a series of in vitro supercoiling relaxation experiments. On the whole, these results suggest that compositional context introduces feedback in synthetic gene networks. As an illustrative example, we show that a design strategy incorporating compositional context effects can improve threshold detection and memory properties of the toggle switch.
]]></description>
<dc:creator>Yeung, E.</dc:creator>
<dc:creator>Dy, A. J.</dc:creator>
<dc:creator>Martin, K. B.</dc:creator>
<dc:creator>Ng, A. H.</dc:creator>
<dc:creator>Del Vecchio, D.</dc:creator>
<dc:creator>Beck, J. L.</dc:creator>
<dc:creator>Collins, J. J.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2016-10-25</dc:date>
<dc:identifier>doi:10.1101/083329</dc:identifier>
<dc:title><![CDATA[The Effect of Compositional Context on Synthetic Gene Net-works]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-10-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/085977v1?rss=1">
<title>
<![CDATA[
Structure of the Legionella Dot/Icm type IV secretion system in situ by electron cryotomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/085977v1?rss=1</link>
<description><![CDATA[
Type IV secretion systems (T4SSs) are large macromolecular machines that translocate protein and DNA and are involved in the pathogenesis of multiple human diseases. Here, using electron cryotomography (ECT), we report the in situ structure of the Dot/Icm type IVB secretion system (T4BSS) utilized by the human pathogen Legionella pneumophila. This is the first structure of a type IVB secretion system, and also the first structure of any T4SS in situ. While the Dot/Icm system shares almost no sequence homology with type IVA secretion systems (T4ASSs), its overall structure shows remarkable similarities to two previously imaged T4ASSs, suggesting shared aspects of mechanism. However, compared to one of these, the negative-stain reconstruction of the purified T4ASS from the R388 plasmid, it is approximately twice as long and wide and exhibits several additional large densities, reflecting type-specific elaborations and potentially better structural preservation in situ.
]]></description>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Chang, Y.-W.</dc:creator>
<dc:creator>Jeong, K. C.</dc:creator>
<dc:creator>Vogel, J. P.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2016-11-07</dc:date>
<dc:identifier>doi:10.1101/085977</dc:identifier>
<dc:title><![CDATA[Structure of the Legionella Dot/Icm type IV secretion system in situ by electron cryotomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-11-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/086553v1?rss=1">
<title>
<![CDATA[
Novel computational method for predicting polytherapy switching strategies to overcome tumor heterogeneity and evolution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/086553v1?rss=1</link>
<description><![CDATA[
1The success of targeted cancer therapy is limited by drug resistance that can result from tumor genetic heterogeneity. The current approach to address resistance typically involves initiating a new treatment after clinical/radiographic disease progression, ultimately resulting in futility in most patients. Towards a potential alternative solution, we developed a novel computational framework that uses human cancer profiling data to systematically identify dynamic, pre-emptive, and sometimes non-intuitive treatment strategies that can better control tumors in real-time. By studying lung adenocarcinoma clinical specimens and preclinical models, our computational analyses revealed that the best anti-cancer strategies addressed existing resistant subpopulations as they emerged dynamically during treatment. In some cases, the best computed treatment strategy used unconventional therapy switching while the bulk tumor was responding, a prediction we confirmed in vitro. The new framework presented here could guide the principled implementation of dynamic molecular monitoring and treatment strategies to improve cancer control.
]]></description>
<dc:creator>Jonsson, V. D.</dc:creator>
<dc:creator>Blakely, C. M.</dc:creator>
<dc:creator>Lin, L.</dc:creator>
<dc:creator>Asthana, S.</dc:creator>
<dc:creator>Olivas, V.</dc:creator>
<dc:creator>Gubens, M. A.</dc:creator>
<dc:creator>Matni, N.</dc:creator>
<dc:creator>Bastian, B. C.</dc:creator>
<dc:creator>Taylor, B. S.</dc:creator>
<dc:creator>Doyle, J. C.</dc:creator>
<dc:creator>Bivona, T. G.</dc:creator>
<dc:date>2016-11-08</dc:date>
<dc:identifier>doi:10.1101/086553</dc:identifier>
<dc:title><![CDATA[Novel computational method for predicting polytherapy switching strategies to overcome tumor heterogeneity and evolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-11-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/087379v1?rss=1">
<title>
<![CDATA[
A Bayesian approach to inferring chemical signal timing and amplitude in a temporal logic gate using the cell population distributional response 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/087379v1?rss=1</link>
<description><![CDATA[
1. Introduction 1. Introduction 2. The temporal logic... 3. Bayesian event detection... 4. Applying the Bayesian... 5. Conclusion References Stochastic gene expression poses an important challenge for engineering robust behaviors in a heterogeneous cell population [1]. Cells address this challenge using the distribution of cellular responses during some gene regulation and differentiation processes [2]. Similarly, the temporal logic gate design in Hsiao et al. [3] considers the distribution of responses across a cell population. The design employs integrases Bxb1 and TP901-1 [4] to engineer an E. coli strain with four DNA states that record the temporal order of two chemical signals. Hsiao et al. [3] also use the heter ...
]]></description>
<dc:creator>Baetica, A.-A.</dc:creator>
<dc:creator>Catanach, T. A.</dc:creator>
<dc:creator>Hsiao, V.</dc:creator>
<dc:creator>Murray, R.</dc:creator>
<dc:creator>Beck, J.</dc:creator>
<dc:date>2016-11-14</dc:date>
<dc:identifier>doi:10.1101/087379</dc:identifier>
<dc:title><![CDATA[A Bayesian approach to inferring chemical signal timing and amplitude in a temporal logic gate using the cell population distributional response]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-11-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/087585v1?rss=1">
<title>
<![CDATA[
Cobalt enrichment in anaerobic microbial cocultures revealed by synchrotron X-ray fluorescence imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/087585v1?rss=1</link>
<description><![CDATA[
Metal cofactors are required for many enzymes in anaerobic microbial respiration. This study examined iron, cobalt, nickel, copper, and zinc in cellular and abiotic phases at the single-cell scale for a sulfate-reducing bacterium (Desulfococcus multivorans) and a methanogenic archaeon (Methanosarcina acetivorans) using synchrotron x-ray fluorescence microscopy. Relative abundances of cellular metals were also measured by inductively coupled plasma mass spectrometry. For both species, zinc and iron were consistently the most abundant cellular metals. M. acetivorans contained higher nickel and cobalt content than D. multivorans, likely due to elevated metal requirements for methylotrophic methanogenesis. Cocultures contained spheroid zinc sulfides and cobalt/copper-sulfides.
]]></description>
<dc:creator>Glass, J. B.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Dawson, K. S.</dc:creator>
<dc:creator>Horton, D. R.</dc:creator>
<dc:creator>Vogt, S.</dc:creator>
<dc:creator>Ingall, E. D.</dc:creator>
<dc:creator>Twining, B. S.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2016-11-14</dc:date>
<dc:identifier>doi:10.1101/087585</dc:identifier>
<dc:title><![CDATA[Cobalt enrichment in anaerobic microbial cocultures revealed by synchrotron X-ray fluorescence imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-11-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/088393v1?rss=1">
<title>
<![CDATA[
Engineered reciprocal chromosome translocations drive high threshold, reversible population replacement in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/088393v1?rss=1</link>
<description><![CDATA[
Replacement of wild insect populations with transgene-bearing individuals unable to transmit disease or survive under specific environmental conditions provides self-perpetuating methods of disease prevention and population suppression, respectively. Gene drive mechanisms that require the gene drive element and linked cargo exceed a high threshold frequency to spread are attractive because they offer several points of control: they bring about local, but not global population replacement; and transgenes can be eliminated by reintroducing wildtypes into the population so as to drive the frequency of transgenes below the threshold required for drive. It has long been recognized that reciprocal chromosome translocations could, in principal, be used to bring about high threshold gene drive through a form of underdominance. However, translocations able to drive population replacement have not been reported, leaving it unclear if translocation-bearing strains fit enough to mediate gene drive can easily be generated. Here we use modeling to identify a range of conditions under which translocations should spread, and the equilibrium frequencies achieved, given specific introduction frequencies, fitness costs and migration rates. We also report the creation of engineered translocation-bearing strains of Drosophila melanogaster, generated through targeted chromosomal breakage and homologous recombination. By several measures translocation-bearing strains are fit, and drive high threshold, reversible population replacement in laboratory populations. These observations, together with the generality of the tools used to generate translocations, suggest that engineered translocations may be useful for controlled population replacement in many species.
]]></description>
<dc:creator>Buchman, A. B.</dc:creator>
<dc:creator>Ivy, T.</dc:creator>
<dc:creator>Marshall, J. M.</dc:creator>
<dc:creator>Akbari, O.</dc:creator>
<dc:creator>Hay, B. A.</dc:creator>
<dc:date>2016-11-17</dc:date>
<dc:identifier>doi:10.1101/088393</dc:identifier>
<dc:title><![CDATA[Engineered reciprocal chromosome translocations drive high threshold, reversible population replacement in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-11-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/089714v1?rss=1">
<title>
<![CDATA[
FlyLimbTracker: an active contour based approach for leg segment tracking in unmarked, freely behaving Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/089714v1?rss=1</link>
<description><![CDATA[
Understanding the biological underpinnings of movement and action requires the development of tools for precise, quantitative, and high-throughput measurements of animal behavior. Drosophila melanogaster provides an ideal model for developing such tools: the fly has unparalleled genetic accessibility and depends on a relatively compact nervous system to generate sophisticated limbed behaviors including walking, reaching, grooming, courtship, and boxing. Here we describe a method that uses active contours to semi-automatically track body and leg segments from video image sequences of unmarked, freely behaving Drosophila. We show that this approach is robust to wide variations in video spatial and temporal resolution and that it can be used to measure leg segment motions during a variety of locomotor and grooming behaviors. FlyLimbTracker, the software implementation of this method, is open-source and our approach is generalizable. This opens up the possibility of tracking leg movements in other species by modifications of underlying active contour models.nnAuthor SummaryIn terrestrial animals, including humans, fundamental actions like locomotion and grooming emerge from the displacement of multiple limbs through space. Therefore, precise measurements of limb movements are critical for investigating and, ultimately, understanding the neural basis for behavior. The vinegar fly, Drosophila melanogaster, is an attractive animal model for uncovering general principles about limb control since its genome and nervous system are easy to manipulate. However, existing methods for measuring leg movements in freely behaving Drosophila have significant drawbacks: they require complicated experimental setups and provide limited information about each leg. Here we report a new method - and provide its open-source software implementation, FlyLimbTracker - for tracking the body and leg segments of freely behaving flies using only computational image processing approaches. We illustrate the power of this method by tracking fly limbs during five distinct walking and grooming behaviors and from videos across a wide range of spatial and temporal resolutions. Our approach is generalizable, allowing researchers to use and customize our software for limb tracking in Drosophila and in other species.
]]></description>
<dc:creator>Uhlmann, V.</dc:creator>
<dc:creator>Ramdya, P.</dc:creator>
<dc:creator>Delgado-Gonzalo, R.</dc:creator>
<dc:creator>Benton, R.</dc:creator>
<dc:creator>Unser, M.</dc:creator>
<dc:date>2016-11-26</dc:date>
<dc:identifier>doi:10.1101/089714</dc:identifier>
<dc:title><![CDATA[FlyLimbTracker: an active contour based approach for leg segment tracking in unmarked, freely behaving Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-11-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/091520v1?rss=1">
<title>
<![CDATA[
Prototyping a valinomycin biosynthesis pathway within a cell-free transcription-translation (TX-TL) system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/091520v1?rss=1</link>
<description><![CDATA[
1Many natural metabolites have antibacterial, antiviral, or anticancer effects and can be developed into new drugs. However, working with the microorganisms that produce these products can be challenging since they are not as well characterized as a model organism like Escherichia coli. In this paper, we investigate the potential for a cell-free transcription-translation (TX-TL) system to provide a rapid prototyping platform for characterizing new genetic pathways. We use the valinomycin biosynthesis pathway as a test case, and we show successful heterologous expression of the heterodimeric valinomycin synthetase (VlmSyn, Vlm1: 374 kDa and Vlm2: 284 kDa) from Strep-tomyces tsusimaensis within the TX-TL system. Using LC-MS analysis, we find that valinomycin is produced at low but detectable levels, even when only one out of the three basic precursors is fed into the system. Our work represents another step towards applying cell-free biosynthesis to the discovery and characterization of new natural products.
]]></description>
<dc:creator>Zhou, T.</dc:creator>
<dc:date>2016-12-04</dc:date>
<dc:identifier>doi:10.1101/091520</dc:identifier>
<dc:title><![CDATA[Prototyping a valinomycin biosynthesis pathway within a cell-free transcription-translation (TX-TL) system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-12-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/098673v1?rss=1">
<title>
<![CDATA[
Decoding sequence-level information to predict membrane protein expression 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/098673v1?rss=1</link>
<description><![CDATA[
The expression of integral membrane proteins (IMPs) remains a major bottleneck in the characterization of this important protein class. IMP expression levels are currently unpredictable, which renders the pursuit of IMPs for structural and biophysical characterization challenging and inefficient. Experimental evidence demonstrates that changes within the nucleotide or amino-acid sequence for a given IMP can dramatically affect expression; yet these observations have not resulted in generalizable approaches to improved expression. Here, we develop a data-driven statistical predictor named IMProve, that, using only sequence information, increases the likelihood of selecting an IMP that expresses in E. coli. The IMProve model, trained on experimental data, combines a set of sequence-derived features resulting in an IMProve score, where higher values have a higher probability of success. The model is rigorously validated against a variety of independent datasets that contain a wide range of experimental outcomes from various IMP expression trials. The results demonstrate that use of the model can more than double the number of successfully expressed targets at any experimental scale. IMProve can immediately be used to identify favorable targets for characterization.
]]></description>
<dc:creator>Saladi, S. M.</dc:creator>
<dc:creator>Muller, A.</dc:creator>
<dc:creator>Javed, N.</dc:creator>
<dc:creator>Clemons, W. M.</dc:creator>
<dc:date>2017-01-05</dc:date>
<dc:identifier>doi:10.1101/098673</dc:identifier>
<dc:title><![CDATA[Decoding sequence-level information to predict membrane protein expression]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-01-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/101477v1?rss=1">
<title>
<![CDATA[
Multiplexed dynamic imaging of genomic loci in single cells by combined CRISPR imaging and DNA sequential FISH 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/101477v1?rss=1</link>
<description><![CDATA[
Visualization of chromosome dynamics allows the investigation of spatiotemporal chromatin organization and its role in gene regulation and other cellular processes. However, current approaches to label multiple genomic loci in live cells have a fundamental limitation in the number of loci that can be labelled and uniquely identified. Here we describe an approach we call "track first and identify later" for multiplexed visualization of chromosome dynamics by combining two techniques: CRISPR labeling and DNA sequential fluorescence in situ hybridization (DNA seqFISH). Our approach first labels and tracks chromosomal loci in live cells with the CRISPR system, then barcodes those loci by DNA seqFISH in fixed cells and resolves their identities. We demonstrate our approach by tracking telomere dynamics, identifying 12 unique subtelomeric regions with variable detection efficiencies, and tracking back the telomere dynamics of respective chromosomes in mouse embryonic stem cells.
]]></description>
<dc:creator>Takei, Y.</dc:creator>
<dc:creator>Shah, S.</dc:creator>
<dc:creator>Harvey, S.</dc:creator>
<dc:creator>Qi, L. S.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:date>2017-01-18</dc:date>
<dc:identifier>doi:10.1101/101477</dc:identifier>
<dc:title><![CDATA[Multiplexed dynamic imaging of genomic loci in single cells by combined CRISPR imaging and DNA sequential FISH]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-01-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/102194v1?rss=1">
<title>
<![CDATA[
Monod-Wyman-Changeux Analysis of Ligand-Gated Ion Channel Mutants 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/102194v1?rss=1</link>
<description><![CDATA[
We present a framework for computing the gating properties of ligand-gated ion channel mutants using the Monod-Wyman-Changeux (MWC) model of allostery. We derive simple analytic formulas for key functional properties such as the leakiness, dynamic range, half-maximal effective concentration ([EC50]), and effective Hill coefficient, and explore the full spectrum of phenotypes that are accessible through mutations. Specifically, we consider mutations in the channel pore of nicotinic acetylcholine receptor (nAChR) and the ligand binding domain of a cyclic nucleotide-gated (CNG) ion channel, demonstrating how each mutation can be characterized as only affecting a subset of the biophysical parameters. In addition, we show how the unifying perspective offered by the MWC model allows us, perhaps surprisingly, to collapse the plethora of dose-response data from different classes of ion channels into a universal family of curves.
]]></description>
<dc:creator>Einav, T.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2017-01-22</dc:date>
<dc:identifier>doi:10.1101/102194</dc:identifier>
<dc:title><![CDATA[Monod-Wyman-Changeux Analysis of Ligand-Gated Ion Channel Mutants]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-01-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/103242v1?rss=1">
<title>
<![CDATA[
The ultrastructure of Shewanella oneidensis MR-1 nanowires revealed by electron cryo-tomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/103242v1?rss=1</link>
<description><![CDATA[
AbstractBacterial nanowires have garnered recent interest as a proposed Extracellular Electron Transfer (EET) pathway that links the bacterial electron transport chain to solid-phase electron acceptors away from the cell. In vivo fluorescence Light Microscopy (fLM) imaging recently showed that Shewanella oneidensis MR-1 nanowires are extensions of the outer membrane that contain EET components. However, their fine structure and distribution of cytochrome electron carriers remained unclear, making it difficult to evaluate the electron transport mechanism along the nanowires. Here, we report high-resolution images of nanowires using Electron Cryo-Tomography (ECT). We developed a robust method for fLM imaging of nanowire growth on electron microscopy grids and used correlative light and electron microscopy to identify and image the same nanowires by ECT. Our results confirm that S. oneidensis nanowires are outer membrane extensions, and further reveal that nanowires are dynamic chains of interconnected Outer Membrane Vesicles (OMVs) with variable dimensions, curvature, and extent of tubulation. Junction densities that potentially stabilize OMV chains are seen between neighboring vesicles in cryotomograms. Our ECT results also provide the first hints of the positions and packing of periplasmic and outer membrane proteins consistent with cytochromes. We observe tight packing of putative cytochromes along lateral patches that extend tens of nanometers, but not across the micrometer scale of whole nanowires. We therefore propose that electron transfer along nanowires involves a combination of direct hopping and diffusive events that link neighboring redox proteins.
]]></description>
<dc:creator>Subramanian, P.</dc:creator>
<dc:creator>Pirbadian, S.</dc:creator>
<dc:creator>El-Naggar, M. Y.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2017-01-28</dc:date>
<dc:identifier>doi:10.1101/103242</dc:identifier>
<dc:title><![CDATA[The ultrastructure of Shewanella oneidensis MR-1 nanowires revealed by electron cryo-tomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-01-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/103499v1?rss=1">
<title>
<![CDATA[
The 4D Nucleome Project 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/103499v1?rss=1</link>
<description><![CDATA[
Summary Summary Background Overview of the goals... Structure of the 4D... Research Plans References The spatial organization of the genome and its dynamics contribute to gene expression and cellular function in normal development as well as in disease. Although we are increasingly well equipped to determine a genomes sequence and linear chromatin composition, studying the three-dimensional organization of the genome with high spatial and temporal resolution remains challenging. The 4D Nucleome Network aims to develop and apply approaches to map the structure and dynamics of the human and mouse genomes in space and time with the long term goal of gaining deeper mechanistic understanding of how the nucleus is organized. The project will develop and benchmark experimental and computational approaches for meas ...
]]></description>
<dc:creator>Dekker, J.</dc:creator>
<dc:creator>Belmont, A. S.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:creator>Leshyk, V. O.</dc:creator>
<dc:creator>Lis, J. T.</dc:creator>
<dc:creator>Lomvardas, S.</dc:creator>
<dc:creator>Mirny, L. A.</dc:creator>
<dc:creator>O'Shea, C. C.</dc:creator>
<dc:creator>Park, P. J.</dc:creator>
<dc:creator>Ren, B.</dc:creator>
<dc:creator>Ritland, J. C.</dc:creator>
<dc:creator>Shendure, J.</dc:creator>
<dc:creator>Zhong, S.</dc:creator>
<dc:creator>The 4D Nucleome Network,</dc:creator>
<dc:date>2017-01-26</dc:date>
<dc:identifier>doi:10.1101/103499</dc:identifier>
<dc:title><![CDATA[The 4D Nucleome Project]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-01-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/104455v1?rss=1">
<title>
<![CDATA[
Expressing Biologically Active Membrane Proteins in a Cell-Free Transcription-Translation Platform 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/104455v1?rss=1</link>
<description><![CDATA[
Cell-free transcription-translation platforms have been widely utilized to express soluble proteins in basic synthetic biological circuit prototyping. From a synthetic biology point of view, it is critical to express membrane proteins in cell-free transcription-translation systems, and use them directly in biocircuits, considering the fact that histidine kinases, G-protein coupled receptors (GPCRs) and other important biosensors are all membrane proteins. Previous studies have expressed membrane proteins in cell-free systems with the help of detergents, liposomes or nanodiscs, but have not demonstrated the ability to prototype circuit behavior for the purpose of testing more complex circuit functions involving membrane-bound proteins. Built on previous efforts, in this work we demonstrated that we could co-translationally express solubilized and active membrane proteins in our cell-free TX-TL platform with membrane-like materials. We first tested the expression of several constructs with {beta}1 and {beta}2 adrenergic receptors in TX-TL and observed significant insoluble membrane protein production. The addition of nanodiscs to the cell free expression system enabled solubilization of membrane proteins. Nanodisc is lipoprotein-based membrane-like material. The activity of {beta}2 adrenergic receptor was tested with both fluorescence and Surface Plasmon Resonance (SPR) binding assays by monitoring the specific binding response of small-molecule binders, carazolol and norepinephrine. Our results suggest that it is promising to use cell-free expression systems to prototype synthetic biocircuits involving single chain membrane proteins without extra procedures. This data made us one step closer to testing complex membrane protein circuits in cell-free environment.
]]></description>
<dc:creator>Guo, S.</dc:creator>
<dc:creator>Vaish, A.</dc:creator>
<dc:creator>Chen, Q.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2017-01-30</dc:date>
<dc:identifier>doi:10.1101/104455</dc:identifier>
<dc:title><![CDATA[Expressing Biologically Active Membrane Proteins in a Cell-Free Transcription-Translation Platform]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-01-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/107722v1?rss=1">
<title>
<![CDATA[
SUPERMAN prevents stamen formation and promotes stem cell termination in the fourth whorl of the Arabidopsis flower 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/107722v1?rss=1</link>
<description><![CDATA[
The molecular and genetic networks underlying the determination of floral organ identity are well studied, but much less is known about how the flower is partitioned into four developmentally distinct whorls. The SUPERMAN gene is required for proper specification of the boundary between stamens in whorl 3 and carpels in whorl 4, as superman mutants exhibit supernumerary stamens but usually lack carpels. However, it has remained unclear whether extra stamens in superman mutants originate from an organ identity change in whorl 4 or the overproliferation of whorl 3. Using live confocal imaging, we show that the extra stamens in superman mutants arise from cells in whorl 4, which change their fate from female to male, while floral stem cells proliferate longer, allowing for the production of additional stamens.
]]></description>
<dc:creator>Prunet, N.</dc:creator>
<dc:creator>Yang, W.</dc:creator>
<dc:creator>Das, P.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:creator>Jack, T. P.</dc:creator>
<dc:date>2017-02-10</dc:date>
<dc:identifier>doi:10.1101/107722</dc:identifier>
<dc:title><![CDATA[SUPERMAN prevents stamen formation and promotes stem cell termination in the fourth whorl of the Arabidopsis flower]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-02-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/108191v1?rss=1">
<title>
<![CDATA[
Uncharacterized bacterial structures revealed by electron cryotomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/108191v1?rss=1</link>
<description><![CDATA[
SUMMARY STATEMENTHere we present a survey of previously uncharacterized structures we have observed in bacterial cells by electron cryotomography, in the hopes of spurring their identification and study.nnABSTRACTElectron cryotomography (ECT) can reveal the native structure and arrangement of macromolecular complexes inside intact cells. This technique has greatly advanced our understanding of the ultrastructure of bacterial cells. Rather than undifferentiated bags of enzymes, we now view bacteria as structurally complex assemblies of macromolecular machines. To date, our group has applied ECT to nearly 90 different bacterial species, collecting more than 15,000 cryotomograms. In addition to known structures, we have observed several, to our knowledge, uncharacterized features in these tomograms. Some are completely novel structures; others expand the features or species range of known structure types. Here we present a survey of these uncharacterized bacterial structures in the hopes of accelerating their identification and study, and furthering our understanding of the structural complexity of bacterial cells.
]]></description>
<dc:creator>Dobro, M. J.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>Piper, A.</dc:creator>
<dc:creator>Cohen, J.</dc:creator>
<dc:creator>Guo, K.</dc:creator>
<dc:creator>Jensen, T.</dc:creator>
<dc:creator>Tadayon, J.</dc:creator>
<dc:creator>Donermeyer, J.</dc:creator>
<dc:creator>Park, Y.</dc:creator>
<dc:creator>Solis, B. A.</dc:creator>
<dc:creator>Kjaer, A.</dc:creator>
<dc:creator>Jewett, A. I.</dc:creator>
<dc:creator>McDowall, A. W.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Chang, Y.-W.</dc:creator>
<dc:creator>Shi, J.</dc:creator>
<dc:creator>Subramanian, P.</dc:creator>
<dc:creator>Iancu, C. V.</dc:creator>
<dc:creator>Li, Z.</dc:creator>
<dc:creator>Briegel, A.</dc:creator>
<dc:creator>Tocheva, E. I.</dc:creator>
<dc:creator>Pilhofer, M.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2017-02-13</dc:date>
<dc:identifier>doi:10.1101/108191</dc:identifier>
<dc:title><![CDATA[Uncharacterized bacterial structures revealed by electron cryotomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-02-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/108209v1?rss=1">
<title>
<![CDATA[
Structure of the archaellar motor and associated cytoplasmic cone in Thermococcus kodakaraensis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/108209v1?rss=1</link>
<description><![CDATA[
Archaeal swimming motility is driven by rotary motors called archaella. The structure of these motors, and particularly how they are anchored in the absence of a peptidoglycan cell wall, is unknown. Here, we use electron cryotomography to visualize the archaellar motor in vivo in Thermococcus kodakaraensis. Compared to the homologous bacterial type IV pilus (T4P), we observe structural similarities as well as several unique features. While the position of the cytoplasmic ATPase appears conserved, it is not braced by linkages that extend upward through the cell envelope as in the T4P, but rather by cytoplasmic components that attach it to a large conical frustum up to 500 nm in diameter at its base. In addition to anchoring the lophotrichous bundle of archaella, the conical frustum associates with chemosensory arrays and ribosome-excluding material and may function as a polar organizing center for the coccoid cells.
]]></description>
<dc:creator>Briegel, A.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>Chang, Y.-W.</dc:creator>
<dc:creator>Kjaer, A.</dc:creator>
<dc:creator>Huang, A. N.</dc:creator>
<dc:creator>Kim, K. W.</dc:creator>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Gunsalus, R. P.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2017-02-13</dc:date>
<dc:identifier>doi:10.1101/108209</dc:identifier>
<dc:title><![CDATA[Structure of the archaellar motor and associated cytoplasmic cone in Thermococcus kodakaraensis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-02-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/108233v1?rss=1">
<title>
<![CDATA[
In vivo structures of an intact type VI secretion system revealed by electron cryotomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/108233v1?rss=1</link>
<description><![CDATA[
The type VI secretion system (T6SS) is a versatile molecular weapon used by many bacteria against eukaryotic hosts or prokaryotic competitors. It consists of a cytoplasmic bacteriophage tail-like structure anchored in the bacterial cell envelope via a cytoplasmic baseplate and a periplasmic membrane complex. Rapid contraction of the sheath in the bacteriophage tail-like structure propels an inner tube/spike complex through the target cell envelope to deliver effectors. While structures of purified contracted sheath and purified membrane complex have been solved, because sheaths contract upon cell lysis and purification, no structure is available for the extended sheath. Structural information about the baseplate is also lacking. Here we use electron cryotomography to directly visualize intact T6SS structures inside Myxococcus xanthus cells. Using sub-tomogram averaging, we resolve the structure of the extended sheath and membrane-associated components including the baseplate. Moreover, we identify novel extracellular bacteriophage tail fiber-like antennae. These results provide new structural insights into how the extended sheath prevents premature disassembly and how this sophisticated machine may recognize targets.
]]></description>
<dc:creator>Chang, Y.-W.</dc:creator>
<dc:creator>Rettberg, L. A.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2017-02-14</dc:date>
<dc:identifier>doi:10.1101/108233</dc:identifier>
<dc:title><![CDATA[In vivo structures of an intact type VI secretion system revealed by electron cryotomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-02-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/109850v1?rss=1">
<title>
<![CDATA[
Model-based spike sorting with a mixture of drifting t-distributions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/109850v1?rss=1</link>
<description><![CDATA[
Chronic extracellular recordings are a powerful tool for systems neuroscience, but spike sorting remains a challenge. A common approach is to fit a generative model, such as a mixture of Gaussians, to the observed spike data. Even if non-parametric methods are used for spike sorting, such generative models provide a quantitative measure of unit isolation quality, which is crucial for subsequent interpretation of the sorted spike trains. We present a spike sorting strategy that models the data as a mixture of drifting t-distributions. This model captures two important features of chronic extracellular recordings--cluster drift over time and heavy tails in the distribution of spikes--and offers improved robustness to outliers. We evaluate this model on several thousand hours of chronic tetrode recordings and show that it fits the empirical data substantially better than a mixture of Gaussians. We also provide a software implementation that can re-fit long datasets (several hours, millions of spikes) in a few seconds, enabling interactive clustering of chronic recordings. Using experimental data, we identify three common failure modes of spike sorting methods that assume stationarity. We also characterize the limitations of several popular unit isolation metrics in the presence of empirically-observed variations in cluster size and scale. We find that the mixture of drifting t-distributions model enables efficient spike sorting of long datasets and provides an accurate measure of unit isolation quality over a wide range of conditions.
]]></description>
<dc:creator>Shan, K. Q.</dc:creator>
<dc:creator>Lubenov, E. V.</dc:creator>
<dc:creator>Siapas, A. G.</dc:creator>
<dc:date>2017-02-20</dc:date>
<dc:identifier>doi:10.1101/109850</dc:identifier>
<dc:title><![CDATA[Model-based spike sorting with a mixture of drifting t-distributions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-02-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/110254v1?rss=1">
<title>
<![CDATA[
Repressing Integrase attachment site operation with CRISPR-Cas9 in E. coli 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/110254v1?rss=1</link>
<description><![CDATA[
Serine integrases are bacteriophage proteins responsible for integrating the phage genome into that of the host. Synthetic biologists have co-opted these proteins into useful tools for permanent DNA logic, utilizing their specific DNA recombination abilities to build synthetic cell differentiation and genetic memory systems. Each integrase has a specific pair of DNA sequences (attP/attB sites) that it recombines, but multiple identical sites can result in unpredictable recombination. We have developed a way to control integrase activity on identical attP/attB sites by using catalytically dead Cas9 (dCas9) as a programmable binding protein that can compete with integrase for binding to specific attachment sites. Utilizing a plasmid that contains two identical Bxb1 attP sites, integration can be repressed up to 8 fold at either one of the two attP sites when guide RNA and dCas9 are present. Guide RNA sequences that bind specifically to attB, or either of two attP sites, have been developed. Future goals are to utilize this technology to construct larger and more complex integrase logic circuits.
]]></description>
<dc:creator>Shur, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2017-02-21</dc:date>
<dc:identifier>doi:10.1101/110254</dc:identifier>
<dc:title><![CDATA[Repressing Integrase attachment site operation with CRISPR-Cas9 in E. coli]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-02-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/111906v1?rss=1">
<title>
<![CDATA[
Engineering pulsatile communication in bacterial consortia 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/111906v1?rss=1</link>
<description><![CDATA[
Lux-type quorum sensing systems enable communication in bacteria with only two protein components: a signal synthase and an inducible transcription activator. The simplicity of these systems makes them a popular choice for engineering collaborative behaviors in synthetic bacterial consortia, such as photographic edge detection and synchronized oscillation. To add to this body of work, we propose a pulsatile communication circuit that enables dynamic patterning and long-distance communication analogous to action potentials traveling through nerve tissue. We employed a model-driven design paradigm involving incremental characterization of in vivo design candidates with increasing circuit complexity. Beginning with a simple inducible reporter system, we screened a small number of circuits varying in their promoter and ribosomal binding site (RBS) strengths. From this candidate pool, we selected a candidate to be the seed network for the subsequent round of more complex circuit variants, likewise variable in promoter and RBS strengths. The selection criteria at each level of complexity is tailored to optimize a different desirable performance characteristic. By this approach we individually optimized reporter signal-to-background ratio, pulsatile response to induction, and quiescent basal transcription, avoiding large library screens while ensuring robust performance of the composite circuit.
]]></description>
<dc:creator>Parkin, J.</dc:creator>
<dc:creator>Hsiao, V.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2017-02-26</dc:date>
<dc:identifier>doi:10.1101/111906</dc:identifier>
<dc:title><![CDATA[Engineering pulsatile communication in bacterial consortia]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-02-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/113340v1?rss=1">
<title>
<![CDATA[
Finding analytic stationary solutions to the chemical master equation by gluing state spaces at one or two states recursively 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/113340v1?rss=1</link>
<description><![CDATA[
Noise is often indispensable to key cellular activities, such as gene expression, necessitating the use of stochastic models to capture its dynamics. The chemical master equation (CME) is a commonly used stochastic model that describes how the probability distribution of a chemically reacting system varies with time. Knowing analytic solutions to the CME can have benefits, such as expediting simulations of multiscale biochemical reaction networks and aiding the design of distributional responses. However, analytic solutions are rarely known. A recent method of computing analytic stationary solutions relies on gluing simple state spaces together recursively at one or two states. We explore the capabilities of this method and introduce algorithms to derive analytic stationary solutions to the CME. We first formally characterise state spaces that can be constructed by performing single-state gluing of paths, cycles or both sequentially. We then study stochastic biochemical reaction networks that consist of reversible, elementary reactions with two-dimensional state spaces. We also discuss extending the method to infinite state spaces and designing stationary distributions that satisfy user-specified constraints. Finally, we illustrate the aforementioned ideas using examples that include two interconnected transcriptional components and chemical reactions with two-dimensional state spaces.nnSubject AreasSystems biology, synthetic biology, biomathematics, bioengineering
]]></description>
<dc:creator>Meng, X. F.</dc:creator>
<dc:creator>Baetica, A.-A.</dc:creator>
<dc:creator>Singhal, V.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2017-03-03</dc:date>
<dc:identifier>doi:10.1101/113340</dc:identifier>
<dc:title><![CDATA[Finding analytic stationary solutions to the chemical master equation by gluing state spaces at one or two states recursively]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-03-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/120253v1?rss=1">
<title>
<![CDATA[
Population regulation in microbial consortia using dual feedback control 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/120253v1?rss=1</link>
<description><![CDATA[
An ongoing area of study in synthetic biology has been the design and construction of synthetic circuits that maintain homeostasis at the population level. Here, we are interested in designing a synthetic control circuit that regulates the total cell population and the relative ratio between cell strains in a culture containing two different cell strains. We have developed a dual feedback control strategy that uses two separate control loops to achieve the two functions respectively. By combining both of these control loops, we have created a population regulation circuit where both the total population size and relative cell type ratio can be set by reference signals. The dynamics of the regulation circuit show robustness and adaptation to perturbations in cell growth rate and changes in cell numbers. The control architecture is general and could apply to any organism for which synthetic biology tools for quorum sensing, comparison between outputs, and growth control are available.
]]></description>
<dc:creator>Ren, X.</dc:creator>
<dc:creator>Baetica, A.-A.</dc:creator>
<dc:creator>Swaminathan, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2017-03-24</dc:date>
<dc:identifier>doi:10.1101/120253</dc:identifier>
<dc:title><![CDATA[Population regulation in microbial consortia using dual feedback control]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-03-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/120642v1?rss=1">
<title>
<![CDATA[
Distinguishing Signal From Autofluorescence In Cryogenic Correlated Light And Electron Microscopy Of Mammalian Cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/120642v1?rss=1</link>
<description><![CDATA[
Cryogenic correlated light and electron microscopy (cryo-CLEM) is a valuable tool for studying biological processes in situ. In cryo-CLEM, a target protein of interest is tagged with a fluorophore and the location of the corresponding fluorescent signal is used to identify the structure in low-contrast but feature-rich cryo-EM images. To date, cryo-CLEM studies of mammalian cells have relied on very bright organic dyes or fluorescent protein tags concentrated in virus particles. Here we describe a method to expand the application of cryo-CLEM to cells harboring genetically-encoded fluorescent proteins. We discovered that a variety of mammalian cells exhibit strong punctate autofluorescence when imaged under cryogenic conditions (80K). Compared to fluorescent protein tags, these sources of autofluorescence exhibit a broader spectrum of fluorescence, which we exploited to develop a simple, robust approach to discriminate between the two. We validate this method in INS-1 E cells using a mitochondrial marker, and apply it to study the ultrastructural variability of secretory granules in a near-native state within intact INS-1E pancreatic cells by high-resolution 3D electron cryotomography.
]]></description>
<dc:creator>Carter, S. D.</dc:creator>
<dc:creator>Mageswaran, S. K.</dc:creator>
<dc:creator>Farino, Z. J.</dc:creator>
<dc:creator>Mamede, J. I.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>Hope, T. J.</dc:creator>
<dc:creator>Freyberg, Z.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2017-03-26</dc:date>
<dc:identifier>doi:10.1101/120642</dc:identifier>
<dc:title><![CDATA[Distinguishing Signal From Autofluorescence In Cryogenic Correlated Light And Electron Microscopy Of Mammalian Cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-03-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/122606v1?rss=1">
<title>
<![CDATA[
Implementation and System Identification of a Phosphorylation-Based Insulator in a Cell-Free Transcription-Translation System 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/122606v1?rss=1</link>
<description><![CDATA[
An outstanding challenge in the design of synthetic biocircuits is the development of a robust and efficient strategy for interconnecting functional modules. Recent work demonstrated that a phosphorylation-based insulator (PBI) implementing a dual strategy of high gain and strong negative feedback can be used as a device to attenuate retroactivity. This paper describes the implementation of such a biological circuit in a cell-free transcription-translation system and the structural identifiability of the PBI in the system. We first show that the retroactivity also exists in the cell-free system by testing a simple negative regulation circuit. Then we demonstrate that the PBI circuit helps attenuate the retroactivity significantly compared to the control. We consider a complex model that provides an intricate description of all chemical reactions and leveraging specific physiologically plausible assumptions. We derive a rigorous simplified model that captures the output dynamics of the PBI. We perform standard system identification analysis and determine that the model is globally identifiable with respect to three critical parameters. These three parameters are identifiable under specific experimental conditions and we perform these experiments to estimate the parameters. Our experimental results suggest that the functional form of our simplified model is sufficient to describe the reporter dynamics and enable parameter estimation. In general, this research illustrates the utility of the cell-free expression system as an alternate platform for biocircuit implementation and system identification and it can provide helpful insights into future biological circuit designs.
]]></description>
<dc:creator>Guo, S.</dc:creator>
<dc:creator>Yeung, E.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2017-03-30</dc:date>
<dc:identifier>doi:10.1101/122606</dc:identifier>
<dc:title><![CDATA[Implementation and System Identification of a Phosphorylation-Based Insulator in a Cell-Free Transcription-Translation System]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-03-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/122903v1?rss=1">
<title>
<![CDATA[
Hypocretin underlies the evolution of sleep loss in the Mexican cavefish 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/122903v1?rss=1</link>
<description><![CDATA[
The duration of sleep varies dramatically between species, yet little is known about genetic bases or evolutionary factors driving this variation in behavior. The Mexican cavefish, Astyanax mexicanus, exists as surface populations that inhabit rivers, and multiple independently derived cave populations with convergent evolution on sleep loss. The number of Hypocretin/Orexin (HCRT)-positive hypothalamic neurons is increased significantly in cavefish, and HCRT is upregulated at both the transcript and protein levels. Pharmacological or genetic inhibition of HCRT signaling increases sleep duration in cavefish without affecting sleep in surface fish, suggesting enhanced HCRT signaling underlies sleep loss in cavefish. Ablation of the lateral line or starvation, manipulations that selectively promote sleep in cavefish, inhibit hcrt expression in cavefish while having little effect in surface fish. These findings provide the first evidence of genetic and neuronal changes that contribute to the evolution of sleep loss, and support a conserved role for HCRT in sleep regulation.
]]></description>
<dc:creator>Jaggard, J. B.</dc:creator>
<dc:creator>Stahl, B. A.</dc:creator>
<dc:creator>Lloyd, E.</dc:creator>
<dc:creator>Duboue, E. R.</dc:creator>
<dc:creator>Keene, A. C.</dc:creator>
<dc:date>2017-03-31</dc:date>
<dc:identifier>doi:10.1101/122903</dc:identifier>
<dc:title><![CDATA[Hypocretin underlies the evolution of sleep loss in the Mexican cavefish]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-03-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/123190v1?rss=1">
<title>
<![CDATA[
Prototyping And Implementation Of A Novel Feedforward Loop In A Cell-Free Transcription-Translation System And Cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/123190v1?rss=1</link>
<description><![CDATA[
Building novel synthetic biological devices is a time-consuming task because of the lengthy cell-based testing and optimization processes. Recent progress made in the cell-free field suggests that the utilization of mathematical models and cell-free transcription-translation testing platforms to systematically design and test novel synthetic biocircuits may help streamline some of the processes. Here we present a study of building a novel functional biological network motif from scratch with the aid of the mathematical modeling and the cell-free prototyping. In this work, we demonstrated that we were able to make a 3-promoter feedforward circuit from a concept to a working biocircuit in cells within a month. We started with performing simulations with a cell-free transcription-translation simulation toolbox. After verifying the feasibility of the circuit design, we used a fast assembling method to build the constructs and used the linear DNAs directly in the cell-free system for prototyping. After additional tests and assemblies, we implemented the circuit in plasmid forms in cells and showed that the in vivo results were consistent with the simulations and the outcomes in the cell-free platform. This study showed the usefulness of modeling and prototyping in building synthetic biocircuits and that we can use these tools to help streamline the process of circuit optimizations in future studies.
]]></description>
<dc:creator>Guo, S.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2017-04-02</dc:date>
<dc:identifier>doi:10.1101/123190</dc:identifier>
<dc:title><![CDATA[Prototyping And Implementation Of A Novel Feedforward Loop In A Cell-Free Transcription-Translation System And Cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-04-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/124214v1?rss=1">
<title>
<![CDATA[
FtsEX-Mediated Regulation Of Inner Membrane Fusion And Cell Separation Reveals Morphogenetic Plasticity In Caulobacter crescentus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/124214v1?rss=1</link>
<description><![CDATA[
During its life cycle, Caulobacter crescentus undergoes a series of coordinated shape changes, including generation of a polar stalk and reshaping of the cell envelope to produce new daughter cells through the process of cytokinesis. The mechanisms by which these morphogenetic processes are coordinated in time and space remain largely unknown. Here we demonstrate that the conserved division complex FtsEX controls both the early and late stages of cytokinesis in C. crescentus, namely initiation of constriction and final cell separation. {Delta}ftsE cells display a striking phenotype: cells are chained, with skinny connections between cell bodies resulting from defects in inner membrane fusion and cell separation. Surprisingly, the thin connections in {Delta}ftsE cells share morphological and molecular features with C. crescentus stalks. Our data uncover unanticipated morphogenetic plasticity in C. crescentus, with loss of FtsE causing a stalk-like program to take over at failed division sites and yield novel cell morphology.nnAuthor SummaryBacterial cell shape is genetically hardwired and is critical for fitness and, in certain cases, pathogenesis. In most bacteria, a semi-rigid structure called the cell wall surrounds the inner membrane, offering protection against cell lysis while simultaneously maintaining cell shape. A highly dynamic macromolecular structure, the cell wall undergoes extensive remodeling as bacterial cells grow and divide. We demonstrate that a broadly conserved cell division complex, FtsEX, relays signals from the cytoplasm to the cell wall to regulate key developmental shape changes in the -proteobacterium Caulobacter crescentus. Consistent with studies in diverse bacteria, we observe strong synthetic interactions between ftsE and cell wall hydrolytic factors, suggesting that regulation of cell wall remodeling is a conserved function of FtsEX. Loss of FtsE causes morphological defects associated with both the early and late stages of division. Intriguingly, without FtsE, cells frequently fail to separate and instead elaborate a thin, tubular structure between cell bodies, a growth mode observed in other -proteobacteria. Overall, our results highlight the plasticity of bacterial cell shape and demonstrate how altering the activity of one morphogenetic program can produce diverse morphologies resembling those of other bacteria in nature.
]]></description>
<dc:creator>Meier, E. L.</dc:creator>
<dc:creator>Yao, Q.</dc:creator>
<dc:creator>Daitch, A. K.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Goley, E. D.</dc:creator>
<dc:date>2017-04-04</dc:date>
<dc:identifier>doi:10.1101/124214</dc:identifier>
<dc:title><![CDATA[FtsEX-Mediated Regulation Of Inner Membrane Fusion And Cell Separation Reveals Morphogenetic Plasticity In Caulobacter crescentus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-04-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/126466v1?rss=1">
<title>
<![CDATA[
Cell type boundaries organize plant development 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/126466v1?rss=1</link>
<description><![CDATA[
In plants the dorsoventral boundary of leaves defines an axis of symmetry through the centre of the organ separating the top (dorsal) and bottom (ventral) tissues. Although the positioning of this boundary is critical for leaf morphogenesis, how the boundary is established and how it influences development remains unclear. Using live-imaging and perturbation experiments we show that leaf orientation, morphology and position are pre-patterned by HD-ZIPIII and KAN gene expression in the shoot, leading to a model in which dorsoventral genes coordinate to regulate plant development by localizing auxin response between their expression domains. However we also find that auxin levels feedback on dorsoventral patterning by spatially organizing HD-ZIPIII and KAN expression in the shoot periphery. By demonstrating that the regulation of these genes by auxin also governs their response to wounds, our results also provide a parsimonious explanation for the influence of wounds on leaf dorsoventrality.nnOnce sentence summaryCell type boundaries regulate plant development
]]></description>
<dc:creator>Heisler, M. G.</dc:creator>
<dc:creator>Caggiano, M. P.</dc:creator>
<dc:creator>Yu, X.</dc:creator>
<dc:creator>Bhatia, N.</dc:creator>
<dc:creator>Larsson, A.</dc:creator>
<dc:creator>Ram, H.</dc:creator>
<dc:creator>Ohno, C. K.</dc:creator>
<dc:creator>Sappl, P.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:creator>Jonsson, H.</dc:creator>
<dc:date>2017-04-11</dc:date>
<dc:identifier>doi:10.1101/126466</dc:identifier>
<dc:title><![CDATA[Cell type boundaries organize plant development]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-04-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/127761v1?rss=1">
<title>
<![CDATA[
Challenges And Emerging Directions In Single-Cell Analysis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/127761v1?rss=1</link>
<description><![CDATA[
Single-cell analysis is a rapidly evolving approach to characterize genome-scale molecular information at the individual cell level. Development of single-cell technologies and computational methods has enabled systematic investigation of cellular heterogeneity in a wide range of tissues and cell populations, yielding fresh insights into the composition, dynamics, and regulatory mechanisms of cell states in development and disease. Despite substantial advances, significant challenges remain in the analysis, integration, and interpretation of single-cell omics data. Here, we discuss the state of the field and recent advances, and look to future opportunities.
]]></description>
<dc:creator>Yuan, G.-C.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:creator>Elowitz, M.</dc:creator>
<dc:creator>Enver, T.</dc:creator>
<dc:creator>Fan, G.</dc:creator>
<dc:creator>Guo, G.</dc:creator>
<dc:creator>Irizarry, R.</dc:creator>
<dc:creator>Kharchenko, P.</dc:creator>
<dc:creator>Kim, J.</dc:creator>
<dc:creator>Orkin, S.</dc:creator>
<dc:creator>Quackenbush, J.</dc:creator>
<dc:creator>Saadatpour, A.</dc:creator>
<dc:creator>Schroeder, T.</dc:creator>
<dc:creator>Shivdasani, R.</dc:creator>
<dc:creator>Tirosh, I.</dc:creator>
<dc:date>2017-04-15</dc:date>
<dc:identifier>doi:10.1101/127761</dc:identifier>
<dc:title><![CDATA[Challenges And Emerging Directions In Single-Cell Analysis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-04-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/129528v1?rss=1">
<title>
<![CDATA[
Ubiquitin and ATP-dependent unfoldase activity of P97/VCP·NPLOC4·UFD1L1 is enhanced by a mutation that causes multisystem proteinopathy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/129528v1?rss=1</link>
<description><![CDATA[
p97 is a  segregase that plays a key role in numerous ubiquitin-dependent pathways, such as ER-associated degradation (ERAD). It has been hypothesized that p97 extracts proteins from membranes or macromolecular complexes to enable their proteasomal degradation; however, the complex nature of p97 substrates has made it difficult to directly observe the fundamental basis for this activity. To address this issue, we developed a soluble p97 substrate--Ub-GFP modified with K48-linked ubiquitin chains--for in vitro p97 activity assays. We demonstrate for the first time that wild type p97 can unfold proteins and that this activity is dependent on the p97 adaptor NPLOC4-UFD1L, ATP hydrolysis, and substrate ubiquitination, with branched chains providing maximal stimulation. Furthermore, we show that a p97 mutant that causes inclusion body myopathy, Pagets Disease of bone, and frontotemporal dementia (IBMPFD) in humans unfolds substrate faster, suggesting that excess activity may underlie pathogenesis. This work overcomes a significant barrier in the study of p97 and will allow the future dissection of p97 mechanism at a level of detail previously unattainable.
]]></description>
<dc:creator>Blythe, E.</dc:creator>
<dc:creator>Olson, K.</dc:creator>
<dc:creator>Chau, V.</dc:creator>
<dc:creator>Deshaies, R.</dc:creator>
<dc:date>2017-04-21</dc:date>
<dc:identifier>doi:10.1101/129528</dc:identifier>
<dc:title><![CDATA[Ubiquitin and ATP-dependent unfoldase activity of P97/VCP·NPLOC4·UFD1L1 is enhanced by a mutation that causes multisystem proteinopathy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-04-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/131946v1?rss=1">
<title>
<![CDATA[
Optimal Sensory Coding By Populations Of ON And OFF Neurons 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/131946v1?rss=1</link>
<description><![CDATA[
In many sensory systems the neural signal is coded by the coordinated response of heterogeneous populations of neurons. What computational benefit does this diversity confer on information processing? We derive an efficient coding framework assuming that neurons have evolved to communicate signals optimally given natural stimulus statistics and metabolic constraints. Incorporating nonlinearities and realistic noise, we study optimal population coding of the same sensory variable using two measures: maximizing the mutual information between stimuli and responses, and minimizing the error incurred by the optimal linear decoder of responses. Our theory is applied to a commonly observed splitting of sensory neurons into ON and OFF that signal stimulus increases or decreases, and to populations of monotonically increasing responses of the same type, ON. Depending on the optimality measure, we make different predictions about how to optimally split a population into ON and OFF, and how to allocate the firing thresholds of individual neurons given realistic stimulus distributions and noise, which accord with certain biases observed experimentally.
]]></description>
<dc:creator>Gjorgjieva, J.</dc:creator>
<dc:creator>Meister, M.</dc:creator>
<dc:creator>Sompolinsky, H.</dc:creator>
<dc:date>2017-04-28</dc:date>
<dc:identifier>doi:10.1101/131946</dc:identifier>
<dc:title><![CDATA[Optimal Sensory Coding By Populations Of ON And OFF Neurons]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-04-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/136242v1?rss=1">
<title>
<![CDATA[
Barcode identification for single cell genomics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/136242v1?rss=1</link>
<description><![CDATA[
Single-cell sequencing experiments use short DNA barcode  tags to identify reads that originate from the same cell. In order to recover single-cell information from such experiments, reads must be grouped based on their barcode tag, a crucial processing step that precedes other computations. However, this step can be difficult due to high rates of mismatch and deletion errors that can afflict barcodes. Here we present an approach to identify and error-correct barcodes by traversing the de Bruijn graph of circularized barcode k-mers. This allows for assignment of reads to consensus fingerprints constructed from k-mers, and we show that for single-cell RNA-Seq this improves the recovery of accurate single-cell transcriptome estimates.
]]></description>
<dc:creator>Tambe, A.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2017-05-09</dc:date>
<dc:identifier>doi:10.1101/136242</dc:identifier>
<dc:title><![CDATA[Barcode identification for single cell genomics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-05-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/137588v1?rss=1">
<title>
<![CDATA[
Responses To Mechanically And Visually Cued Water Waves In The Nervous System Of The Medicinal Leech 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/137588v1?rss=1</link>
<description><![CDATA[
Summary statementCues from water movement help aquatic predators find their prey. We study how the nervous system of the medicinal leech processes visual and mechanical information derived from surface waves.nnAbstractSensitivity to water waves is a key modality by which aquatic predators can detect and localize their prey. For one such predator, the medicinal leech, Hirudo verbana, behavioral responses to visual and mechanical cues from water waves are well documented. Here, we quantitatively characterized the response patterns of a multisensory interneuron, the S cell, to mechanically and visually cued water waves. The frequency dependence of the S-cell response matched the behavioral response well, in that sensitivity was higher for low frequencies in the visual modality and for high frequencies in the mechanical modality. We demonstrated that neither the cephalic ganglia nor the tail brain is required for the S cell to respond to visually cued water waves. The direction of spike propagation within the S- cell system did follow the direction of wave propagation under certain circumstances, but it is unlikely that downstream neuronal targets can use this information. In terms of overall firing rate, the S cell response was not direction selective. Accordingly we propose a role for the S cell in the detection of waves but not in the localization of their source.
]]></description>
<dc:creator>Lehmkuhl, A. M.</dc:creator>
<dc:creator>Muthusamy, A.</dc:creator>
<dc:creator>Wagenaar, D. A.</dc:creator>
<dc:date>2017-05-13</dc:date>
<dc:identifier>doi:10.1101/137588</dc:identifier>
<dc:title><![CDATA[Responses To Mechanically And Visually Cued Water Waves In The Nervous System Of The Medicinal Leech]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-05-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/138420v1?rss=1">
<title>
<![CDATA[
Enzyme-Free Nucleic Acid Dynamical Systems 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/138420v1?rss=1</link>
<description><![CDATA[
Chemistries exhibiting complex dynamics--from inorganic oscillators to gene regulatory networks--have been long known but either cannot be reprogrammed at will, or rely on the sophisticated chemistry underlying the central dogma. Can simpler molecular mechanisms, designed from scratch, exhibit the same range of behaviors? Abstract coupled chemical reactions have been proposed as a programming language for complex dynamics, along with their systematic implementation using short synthetic DNA molecules. We developed this technology for dynamical systems, identifying critical design principles and codifying them into a compiler automating the design process. Using this approach, we built an oscillator containing only DNA components, establishing that Watson-Crick base pairing interactions alone suffice for arbitrarily complex dynamics. Our results argue that autonomous molecular systems that interact with and control their chemical environment can be designed via molecular programming languages.
]]></description>
<dc:creator>Srinivas, N.</dc:creator>
<dc:creator>Parkin, J.</dc:creator>
<dc:creator>Seelig, G.</dc:creator>
<dc:creator>Winfree, E.</dc:creator>
<dc:creator>Soloveichik, D.</dc:creator>
<dc:date>2017-05-16</dc:date>
<dc:identifier>doi:10.1101/138420</dc:identifier>
<dc:title><![CDATA[Enzyme-Free Nucleic Acid Dynamical Systems]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-05-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/145144v1?rss=1">
<title>
<![CDATA[
Whole-Ganglion Imaging Of Voltage In The Medicinal Leech Using A Double-Sided Microscope 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/145144v1?rss=1</link>
<description><![CDATA[
Studies of neuronal network emergence during sensory processing and motor control are greatly promoted by technologies that allow us to simultaneously record the membrane potential dynamics of a large population of neurons in single cell resolution. To achieve whole-brain recording with the ability to detect both small synaptic potentials and action potentials, we developed a voltage-sensitive dye (VSD) imaging technique based on a double-sided microscope that can image two sides of a nervous system simultaneously. We applied this system to the segmental ganglia of the medicinal leech. Double-sided VSD imaging enabled simultaneous recording of membrane potential events from almost all of the identifiable neurons. Using data obtained from double-sided VSD imaging we analyzed neuronal dynamics in both sensory processing and generation of behavior and constructed functional maps for identification of neurons contributing to these processes.
]]></description>
<dc:creator>Tomina, Y.</dc:creator>
<dc:creator>Wagenaar, D. A.</dc:creator>
<dc:date>2017-06-02</dc:date>
<dc:identifier>doi:10.1101/145144</dc:identifier>
<dc:title><![CDATA[Whole-Ganglion Imaging Of Voltage In The Medicinal Leech Using A Double-Sided Microscope]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-06-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/159079v1?rss=1">
<title>
<![CDATA[
Column subset selection for single-cell RNA-Seq clustering 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/159079v1?rss=1</link>
<description><![CDATA[
The first step in the analysis of single-cell RNA sequencing (scRNA-Seq) is dimensionality reduction, which reduces noise and simplifies data visualization. However, techniques such as principal components analysis (PCA) fail to preserve non-negativity and sparsity structures present in the original matrices, and the coordinates of projected cells are not easily interpretable. Commonly used thresholding methods avoid those pitfalls, but ignore collinearity and covariance in the original matrix. We show that a deterministic column subset selection (DCSS) method possesses many of the favorable properties of PCA and common thresholding methods, while avoiding pitfalls from both. We derive new spectral bounds for DCSS. We apply DCSS to two measures of gene expression from two scRNA-Seq experiments with different clustering workflows, and compare to three thresholding methods. In each case study, the clusters based on the small subset of the complete gene expression profile selected by DCSS are similar to clusters produced from the full set. The resulting clusters are informative for cell type.
]]></description>
<dc:creator>McCurdy, S.</dc:creator>
<dc:creator>Ntranos, V.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2017-07-03</dc:date>
<dc:identifier>doi:10.1101/159079</dc:identifier>
<dc:title><![CDATA[Column subset selection for single-cell RNA-Seq clustering]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-07-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/159988v1?rss=1">
<title>
<![CDATA[
Cell-free and in vivo characterization of Lux, Las, and Rpa quorum activation systems in E. coli 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/159988v1?rss=1</link>
<description><![CDATA[
Synthetic biologists have turned towards quorum systems as a path for building sophisticated microbial consortia that exhibit group decision making. Currently, however, even the most complex consortium circuits rely on only one or two quorum sensing systems, greatly restricting the available design space. High-throughput characterization of available quorum sensing systems is useful for finding compatible sets of systems that are suitable for a defined circuit architecture. Recently, cell-free systems have gained popularity as a test-bed for rapid prototyping of genetic circuitry.nnWe take advantage of the transcription-translation cell-free system to characterize three commonly used Lux-type quorum activators, Lux, Las, and Rpa. We then compare the cell-free characterization to results obtained in vivo. We find significant genetic crosstalk in both the Las and Rpa systems and substantial signal crosstalk in Lux activation. We show that cell-free characterization predicts crosstalk observed in vivo.
]]></description>
<dc:creator>Halleran, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2017-07-07</dc:date>
<dc:identifier>doi:10.1101/159988</dc:identifier>
<dc:title><![CDATA[Cell-free and in vivo characterization of Lux, Las, and Rpa quorum activation systems in E. coli]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-07-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/162842v1?rss=1">
<title>
<![CDATA[
Monomerization of Far-Red Fluorescent Proteins 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/162842v1?rss=1</link>
<description><![CDATA[
Anthozoa class red fluorescent proteins (RFPs) are frequently used as biological markers, with far-red emitting variants ({lambda}em ~ 600 - 900 nm) sought for whole animal imaging because biological tissues are permeable to light in this range. A barrier to the use of naturally occurring RFP variants as molecular markers is that all are tetrameric, which is not ideal for cell biological applications. Efforts to engineer monomeric RFPs have usually produced dimmer and blue-shifted variants, as the chromophore is sensitive to small structural perturbations. In fact, despite much effort, only four native RFPs have been successfully monomerized, leaving the vast majority of RFP biodiversity untapped in biomarker development. Here we report the generation of monomeric variants of HcRed and mCardinal, both far-red dimers, and describe a comprehensive methodology for the rapid monomerization of novel red-shifted oligomeric RFPs. Among the resultant variants, is mKelly1 (emission maximum: {lambda}em = 656 nm), which along with the recently reported mGarnet2 (1), forms a new class of bright, monomeric, far-red FPs.
]]></description>
<dc:creator>Wannier, T. M.</dc:creator>
<dc:creator>Gillespie, S.</dc:creator>
<dc:creator>Hutchins, N.</dc:creator>
<dc:creator>McIsaac, R. S.</dc:creator>
<dc:creator>Brown, K. S.</dc:creator>
<dc:creator>Mayo, S. L.</dc:creator>
<dc:date>2017-07-20</dc:date>
<dc:identifier>doi:10.1101/162842</dc:identifier>
<dc:title><![CDATA[Monomerization of Far-Red Fluorescent Proteins]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-07-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/163402v1?rss=1">
<title>
<![CDATA[
Heterogeneous Responses of Hematopoietic Stem Cells to Inflammatory Stimuli are Altered with Age 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/163402v1?rss=1</link>
<description><![CDATA[
Long-term hematopoietic stem cells (LT-HSCs) maintain hematopoietic output throughout an animal's lifespan. With age, however, they produce a myeloid-biased output that may lead to poor immune responses to infectious challenge and the development of myeloid leukemias. Here, we show that young and aged LT-HSCs respond differently to inflammatory stress, such that aged LT-HSCs produce a cell-intrinsic, myeloid-biased expression program. Using single-cell RNA-seq, we identify a myeloid-biased subset within the LT-HSC population (mLT-HSCs) that is much more common amongst aged LT-HSCs and is uniquely primed to respond to acute inflammatory challenge. We predict several transcription factors to regulate differentially expressed genes between mLT-HSCs and other LT-HSC subsets. Among these, we show that Klf5, Ikzf1 and Stat3 play important roles in age-related inflammatory myeloid bias. These factors may regulate myeloid versus lymphoid balance with age, and can potentially mitigate the long-term deleterious effects of inflammation that lead to hematopoietic pathologies.nnHighlightsO_LILT-HSCs from young and aged mice have differential responses to acute inflammatory challenge.nC_LIO_LIHSPCs directly sense inflammatory stimuli in vitro and have a robust transcriptional response.nC_LIO_LIAged LT-HSCs demonstrate a cell-intrinsic myeloid bias during inflammatory challenge.nC_LIO_LISingle-cell RNA-seq unmasked the existence of two subsets within the LT-HSC population that was apparent upon stimulation but not steady-state. One of the LT-HSC subsets is more prevalent in young and the other in aged mice.nC_LIO_LIKlf5, Ikzf1 and Stat3 regulate age- and inflammation-related LT-HSC myeloid-bias.nC_LInnOne sentence summaryMurine hematopoietic stem cells display transcriptional heterogeneity that is quantitatively altered with age and leads to the age-dependent myeloid bias evident after inflammatory challenge.
]]></description>
<dc:creator>Mann, M.</dc:creator>
<dc:creator>Mehta, A.</dc:creator>
<dc:creator>de Boer, C.</dc:creator>
<dc:creator>Kowalczyk, M. S.</dc:creator>
<dc:creator>Lee, K.</dc:creator>
<dc:creator>Farouq, D.</dc:creator>
<dc:creator>Regev, A.</dc:creator>
<dc:creator>Baltimore, D.</dc:creator>
<dc:date>2017-07-13</dc:date>
<dc:identifier>doi:10.1101/163402</dc:identifier>
<dc:title><![CDATA[Heterogeneous Responses of Hematopoietic Stem Cells to Inflammatory Stimuli are Altered with Age]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-07-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/166322v1?rss=1">
<title>
<![CDATA[
Fusion detection and quantification by pseudoalignment 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/166322v1?rss=1</link>
<description><![CDATA[
RNA sequencing in cancer cells is a powerful technique to detect chromosomal rearrangements, allowing for de novo discovery of actively expressed fusion genes. Here we focus on the problem of detecting gene fusions from raw sequencing data, assembling the reads to define fusion transcripts and their associated breakpoints, and quantifying their abundances. Building on the pseudoalignment idea that simplifies and accelerates transcript quantification, we introduce a novel approach to fusion detection based on inspecting paired reads that cannot be pseudoaligned due to conflicting matches. The method and software, called pizzly, filters false positives, assembles new transcripts from the fusion reads, and reports candidate fusions. With pizzly, fusion detection from raw RNA-Seq reads can be performed in a matter of minutes, making the program suitable for the analysis of large cancer gene expression databases and for clinical use. pizzly is available at https://github.com/pmelsted/pizzly
]]></description>
<dc:creator>Melsted, P.</dc:creator>
<dc:creator>Hateley, S.</dc:creator>
<dc:creator>Joseph, I. C.</dc:creator>
<dc:creator>Pimentel, H.</dc:creator>
<dc:creator>Bray, N. L.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2017-07-20</dc:date>
<dc:identifier>doi:10.1101/166322</dc:identifier>
<dc:title><![CDATA[Fusion detection and quantification by pseudoalignment]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-07-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/166652v1?rss=1">
<title>
<![CDATA[
Systematic mapping of chromatin state landscapes during mouse development 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/166652v1?rss=1</link>
<description><![CDATA[
Embryogenesis requires epigenetic information that allows each cell to respond appropriately to developmental cues. Histone modifications are core components of a cells epigenome, giving rise to chromatin states that modulate genome function. Here, we systematically profile histone modifications in a diverse panel of mouse tissues at 8 developmental stages from 10.5 days post conception until birth, performing a total of 1,128 ChIP-seq assays across 72 distinct tissue-stages. We combine these histone modification profiles into a unified set of chromatin state annotations, and track their activity across developmental time and space. Through integrative analysis we identify dynamic enhancers, reveal key transcriptional regulators, and characterize the role of chromatin-based repression in developmental gene regulation. We also leverage these data to link enhancers to putative target genes, revealing connections between coding and non-coding sequence variation in disease etiology. Our study provides a compendium of resources for biomedical researchers, and achieves the most comprehensive view of embryonic chromatin states to date.
]]></description>
<dc:creator>Gorkin, D.</dc:creator>
<dc:creator>Barozzi, I.</dc:creator>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Lee, A. Y.</dc:creator>
<dc:creator>Lee, B.</dc:creator>
<dc:creator>Zhao, Y.</dc:creator>
<dc:creator>Wildberg, A.</dc:creator>
<dc:creator>Ding, B.</dc:creator>
<dc:creator>Zhang, B.</dc:creator>
<dc:creator>Wang, M.</dc:creator>
<dc:creator>Strattan, J. S.</dc:creator>
<dc:creator>Davidson, J. M.</dc:creator>
<dc:creator>Qiu, Y.</dc:creator>
<dc:creator>Afzal, V.</dc:creator>
<dc:creator>Akiyama, J. A.</dc:creator>
<dc:creator>Plajzer-Frick, I.</dc:creator>
<dc:creator>Pickle, C. S.</dc:creator>
<dc:creator>Kato, M.</dc:creator>
<dc:creator>Garvin, T. H.</dc:creator>
<dc:creator>Pham, Q. T.</dc:creator>
<dc:creator>Harrington, A. N.</dc:creator>
<dc:creator>Mannion, B. J.</dc:creator>
<dc:creator>Lee, E. A.</dc:creator>
<dc:creator>Fukuda-Yuzawa, Y.</dc:creator>
<dc:creator>He, Y.</dc:creator>
<dc:creator>Preissl, S.</dc:creator>
<dc:creator>Chee, S.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>Trout, D.</dc:creator>
<dc:creator>Amrhein, H.</dc:creator>
<dc:creator>Yang, H.</dc:creator>
<dc:creator>Cherry, J. M.</dc:creator>
<dc:creator>Shen, Y.</dc:creator>
<dc:creator>Ecker, J. R.</dc:creator>
<dc:creator>Wang, W.</dc:creator>
<dc:creator>Dickel, D. E.</dc:creator>
<dc:creator>Visel, A.</dc:creator>
<dc:creator>Pennacchio, L. A.</dc:creator>
<dc:creator>Ren, B.</dc:creator>
<dc:date>2017-07-21</dc:date>
<dc:identifier>doi:10.1101/166652</dc:identifier>
<dc:title><![CDATA[Systematic mapping of chromatin state landscapes during mouse development]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-07-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/166744v1?rss=1">
<title>
<![CDATA[
Spatiotemporal DNA Methylome Dynamics of the Developing Mammalian Fetus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/166744v1?rss=1</link>
<description><![CDATA[
Genetic studies have revealed an essential role for cytosine DNA methylation in mammalian development. However, its spatiotemporal distribution in the developing embryo remains obscure. Here, we profiled the methylome landscapes of 12 mouse tissues/organs at 8 developmental stages spanning from early embryogenesis to birth. Indepth analysis of these spatiotemporal epigenome maps systematically delineated ~2 million methylation variant regions and uncovered widespread methylation dynamics at nearly one-half million tissue-specific enhancers, whose human counterparts were enriched for variants involved in genetic diseases. Strikingly, these predicted regulatory elements predominantly lose CG methylation during fetal development, whereas the trend is reversed after birth. Accumulation of non-CG methylation within gene bodies of key developmental transcription factors coincided with their transcriptional repression during later stages of fetal development. These spatiotemporal epigenomic maps provide a valuable resource for studying gene regulation during mammalian tissue/organ progression and for pinpointing regulatory elements involved in human developmental diseases.
]]></description>
<dc:creator>He, Y.</dc:creator>
<dc:creator>Hariharan, M.</dc:creator>
<dc:creator>Gorkin, D. U.</dc:creator>
<dc:creator>Dickel, D. E.</dc:creator>
<dc:creator>Luo, C.</dc:creator>
<dc:creator>Castanon, R. G.</dc:creator>
<dc:creator>Nery, J. R.</dc:creator>
<dc:creator>Lee, A. Y.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>Trout, D.</dc:creator>
<dc:creator>Amrhein, H.</dc:creator>
<dc:creator>Fang, R.</dc:creator>
<dc:creator>Chen, H.</dc:creator>
<dc:creator>Li, B.</dc:creator>
<dc:creator>Visel, A.</dc:creator>
<dc:creator>Pennacchio, L.</dc:creator>
<dc:creator>Ren, B.</dc:creator>
<dc:creator>Ecker, J.</dc:creator>
<dc:date>2017-07-21</dc:date>
<dc:identifier>doi:10.1101/166744</dc:identifier>
<dc:title><![CDATA[Spatiotemporal DNA Methylome Dynamics of the Developing Mammalian Fetus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-07-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/167874v1?rss=1">
<title>
<![CDATA[
Tau Internalization is Regulated by 6-O Sulfation on Heparan Sulfate Proteoglycans (HSPGs) 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/167874v1?rss=1</link>
<description><![CDATA[
The misfolding and accumulation of tau protein into intracellular aggregates known as neurofibrillary tangles is a pathological hallmark of neurodegenerative diseases such as Alzheimers disease. However, while tau propagation is a known marker for disease progression, exactly how tau propagates from one cell to another and what mechanisms govern this spread are still unclear. Here, we report that cellular internalization of tau is regulated by quaternary structure and have developed a cellular assay to screen for genetic modulators of tau uptake. Using CRISPRi technology we have tested 3200 genes for their ability to regulate tau entry and identified enzymes in the heparan sulfate proteoglycan biosynthetic pathway as key regulators. We show that 6-O-sulfation is critical for tauheparan sulfate interactions and that this modification regulates uptake in human central nervous system cell lines, iPS-derived neurons, and mouse organotypic brain slice culture. Together, these results suggest novel strategies to halt tau transmission.
]]></description>
<dc:creator>Rauch, J.</dc:creator>
<dc:creator>Chen, J. J.</dc:creator>
<dc:creator>Sorum, A. W.</dc:creator>
<dc:creator>Miller, G. M.</dc:creator>
<dc:creator>Sharf, T.</dc:creator>
<dc:creator>See, S. K.</dc:creator>
<dc:creator>Hsieh-Wilson, L. C.</dc:creator>
<dc:creator>Kampmann, M.</dc:creator>
<dc:creator>Kosik, K. S.</dc:creator>
<dc:date>2017-07-24</dc:date>
<dc:identifier>doi:10.1101/167874</dc:identifier>
<dc:title><![CDATA[Tau Internalization is Regulated by 6-O Sulfation on Heparan Sulfate Proteoglycans (HSPGs)]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-07-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/172007v1?rss=1">
<title>
<![CDATA[
System-level studies of a cell-free transcription-translation platform for metabolic engineering 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/172007v1?rss=1</link>
<description><![CDATA[
Current methods for assembling biosynthetic pathways in microorganisms require a process of repeated trial and error and have long design-build-test cycles. We describe the use of a cell-free transcription-translation (TX-TL) system as a biomolecular breadboard for the rapid engineering of the 1,4-butanediol (BDO) pathway. We demonstrate the reliability of TX-TL as a platform for engineering biological systems by undertaking a careful characterization of its transcription and translation capabilities and provide a detailed analysis of its metabolic output. Using TX-TL to survey the design space of the BDO pathway enables rapid tuning of pathway enzyme expression levels for improved product yield. Leveraging TX-TL to screen enzyme variants for improved catalytic activity accelerates design iterations that can be directly applied to in vivo strain development.
]]></description>
<dc:creator>Wu, Y. Y.</dc:creator>
<dc:creator>Sato, H.</dc:creator>
<dc:creator>Huang, H.</dc:creator>
<dc:creator>Culler, S. J.</dc:creator>
<dc:creator>Khandurina, J.</dc:creator>
<dc:creator>Nagarajan, H.</dc:creator>
<dc:creator>Yang, T. H.</dc:creator>
<dc:creator>Van Dien, S.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2017-08-03</dc:date>
<dc:identifier>doi:10.1101/172007</dc:identifier>
<dc:title><![CDATA[System-level studies of a cell-free transcription-translation platform for metabolic engineering]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-08-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/172726v1?rss=1">
<title>
<![CDATA[
Modulation of host learning in Aedes aegypti mosquitoes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/172726v1?rss=1</link>
<description><![CDATA[
How mosquitoes determine which individuals to bite has important epidemiological consequences. This choice is not random; most mosquitoes specialize in one or a few vertebrate host species, and some individuals in a host population are preferred over others. Here we show that aversive olfactory learning contributes to mosquito preference both between and within host species. Combined electrophysiological and behavioural recordings from tethered flying mosquitoes demonstrated that these odours evoke changes in both behaviour and antennal lobe (AL) neuronal responses. Using electrophysiological and behavioural approaches, and CRISPR gene editing, we demonstrate that dopamine plays a critical role in aversive olfactory learning and modulating odour-evoked responses in AL neurons. Collectively, these results provide the first experimental evidence that olfactory learning in mosquitoes can play an epidemiological role.
]]></description>
<dc:creator>Vinauger, C.</dc:creator>
<dc:creator>Lahondere, C.</dc:creator>
<dc:creator>Wolff, G.</dc:creator>
<dc:creator>Locke, L.</dc:creator>
<dc:creator>Liaw, J.</dc:creator>
<dc:creator>Parrish, J.</dc:creator>
<dc:creator>Akbari, O.</dc:creator>
<dc:creator>Dickinson, M.</dc:creator>
<dc:creator>Riffell, J.</dc:creator>
<dc:date>2017-08-04</dc:date>
<dc:identifier>doi:10.1101/172726</dc:identifier>
<dc:title><![CDATA[Modulation of host learning in Aedes aegypti mosquitoes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-08-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/178590v1?rss=1">
<title>
<![CDATA[
Accurate typing of class I human leukocyte antigen by Oxford nanopore sequencing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/178590v1?rss=1</link>
<description><![CDATA[
Oxford Nanopore Technologies MinION has expanded the current DNA sequencing toolkit by delivering long read lengths and extreme portability. The MinION has the potential to enable expedited point-of-care human leukocyte antigen (HLA) typing, an assay routinely used to assess the immunological compatibility between organ donors and recipients, but the platforms high error rate makes it challenging to type alleles with clinical-grade accuracy. Here, we developed and validated Athlon, an algorithm that iteratively scores nanopore reads mapped to a hierarchical database of HLA alleles to arrive at a consensus diploid genotype; Athlon achieved a 100% accuracy in class I HLA typing at high resolution.
]]></description>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Xiao, F.</dc:creator>
<dc:creator>Hoisington-Lopez, J.</dc:creator>
<dc:creator>Lang, K.</dc:creator>
<dc:creator>Quenzel, P.</dc:creator>
<dc:creator>Duffy, B.</dc:creator>
<dc:creator>Mitra, R. D.</dc:creator>
<dc:date>2017-08-20</dc:date>
<dc:identifier>doi:10.1101/178590</dc:identifier>
<dc:title><![CDATA[Accurate typing of class I human leukocyte antigen by Oxford nanopore sequencing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-08-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/178954v1?rss=1">
<title>
<![CDATA[
The role of stimulus similarity on the summation effect in human causal learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/178954v1?rss=1</link>
<description><![CDATA[
Several contemporary models of associative learning anticipate that the higher responding to a compound of two cues separately trained with a common outcome than to each of the cues alone -a summation effect-is modulated by the similarity between the cues forming the compound. Here, we explored this hypothesis in a series of causal learning experiments with humans. Participants were presented with two visual cues that separately predicted a common outcome and later asked for the outcome predicted by the compound of the two cues. Importantly, the cues similarity was varied between groups through changes in shape, spatial position, color, configuration and rotation. In variance with the predictions of these models, we observed similar and strong levels of summation in both groups across all manipulations of similarity (Experiments 1-5). The summation effect was significantly reduced by manipulations intended to impact assumptions about the causal independence of the cues forming the compound, but this reduction was independent of stimulus similarity (Experiment 6). These results are problematic for similarity-based models and can be more readily explained by rational approaches to causal learning.
]]></description>
<dc:creator>Perez, O. D.</dc:creator>
<dc:creator>San Martin, R.</dc:creator>
<dc:creator>Soto, F. A.</dc:creator>
<dc:date>2017-08-21</dc:date>
<dc:identifier>doi:10.1101/178954</dc:identifier>
<dc:title><![CDATA[The role of stimulus similarity on the summation effect in human causal learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-08-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/180281v1?rss=1">
<title>
<![CDATA[
What if you are not certain? A common computation underlying action selection, reaction time and confidence judgment 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/180281v1?rss=1</link>
<description><![CDATA[
From what to wear to a friends party, to whether to stay in academia or pursue a career in industry, nearly all of our decisions are accompanied by a degree of confidence that provides an assessment of the expected outcome. Although significant progress has been made in understanding the computations underlying confidence judgment, the preponderance of studies focuses on perceptual decisions, in which individuals sequentially sample noisy information and accumulate it as evidence until a threshold is exceeded. Once a decision is made, they initiate an action to implement the choice. However, we often have to make decisions during ongoing actions in dynamic environments where the value and the availability of the alternative options can change with time and previous actions. The current study aims to decipher the computations underlying confidence judgment in action decisions that are made in a dynamic environment. Using a reaching task in which movements are initiated to multiple potential targets, we show that action selection, reaction time and choice confidence all emerge from a common computation in which parallel prepared actions compete based on the overall desirability of targets and action plans.
]]></description>
<dc:creator>Christopoulos, V.</dc:creator>
<dc:creator>Enachescu, V.</dc:creator>
<dc:creator>Schrater, P.</dc:creator>
<dc:creator>Schaal, S.</dc:creator>
<dc:date>2017-08-24</dc:date>
<dc:identifier>doi:10.1101/180281</dc:identifier>
<dc:title><![CDATA[What if you are not certain? A common computation underlying action selection, reaction time and confidence judgment]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-08-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/194902v1?rss=1">
<title>
<![CDATA[
Structure of the fission yeast actomyosin ring during constriction 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/194902v1?rss=1</link>
<description><![CDATA[
Cell division in many eukaryotes is driven by a ring containing actin and myosin. While much is known about the main proteins involved, the precise arrangement of actin filaments within the contractile machinery, and how force is transmitted to the membrane remains unclear. Here we use cryosectioning and cryo-focused ion beam milling to gain access to cryo-preserved actomyosin rings in Schizosaccharomyces pombe for direct three-dimensional imaging by electron cryotomography. Our results show that straight, overlapping actin filaments, running nearly parallel to each other and to the membrane, form a loose bundle of approximately 150 nm in diameter that "saddles" the inward-bending membrane at the leading edge of the division septum. The filaments do not make direct contact with the membrane. Our analysis of the actin filaments reveals the variability in filament number, nearest-neighbor distances between filaments within the bundle, their distance from the membrane and angular distribution with respect to the membrane.nnSignificance StatementMost eukaryotic cells divide using a contractile actomyosin ring, but its structure is unknown. Here we use new specimen preparation methods and electron cryotomography to image constricting rings directly in 3D, in a near-native state in the model organism Schizosaccharomyces pombe. Our images reveal the arrangement of individual actin filaments within the contracting actomyosin ring.
]]></description>
<dc:creator>Swulius, M. T.</dc:creator>
<dc:creator>Nguyen, L. T.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Ortega, D. R.</dc:creator>
<dc:creator>Aich, S.</dc:creator>
<dc:creator>Mishra, M.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2017-10-31</dc:date>
<dc:identifier>doi:10.1101/194902</dc:identifier>
<dc:title><![CDATA[Structure of the fission yeast actomyosin ring during constriction]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/194910v1?rss=1">
<title>
<![CDATA[
Coarse-grained simulations of actomyosin rings point to a nodeless model involving both unipolar and bipolar myosins 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/194910v1?rss=1</link>
<description><![CDATA[
Cytokinesis in most eukaryotic cells is orchestrated by a contractile actomyosin ring. While many of the proteins involved are known, the mechanism of constriction remains unclear. Informed by existing literature and new 3D molecular details from electron cryotomography, here we develop 3D coarse-grained models of actin filaments, unipolar and bipolar myosins, actin crosslinkers, and membranes and simulate their nteractions. Exploring a matrix of possible actomyosin configurations suggested that node-based architectures ike those presently described for ring assembly result in membrane puckers not seen in EM images of real cells. Instead, the model that best matches data from fluorescence microscopy, electron cryotomography, and biochemical experiments is one in which actin filaments transmit force to the membrane through evenly-distributed, membrane-attached, unipolar myosins, with bipolar myosins in the ring driving contraction. While at this point this model is only favored (not proven), the work highlights the power of coarse-grained biophysical simulations to compare complex mechanistic hypotheses.nnSignificance StatementIn most eukaryotes, a ring of actin and myosin drives cell division, but how the elements of the ring are arranged and constrict remain unclear. Here we use 3D coarse-grained simulations to explore various possibilities. Our simulations suggest that if actomyosin is arranged in nodes (as suggested by a popular model of ring assembly), the membrane distorts in ways not seen experimentally. Instead, actin and myosin are more ikely uniformly distributed around the ring. In the model that best fits experimental data, ring tension is generated by interactions between bipolar myosins and actin, and transmitted to the membrane via unipolar myosins. Technologically the study highlights how coarse-grained simulations can test specific mechanistic hypotheses by comparing their predicted outcomes to experimental results.
]]></description>
<dc:creator>Nguyen, L.</dc:creator>
<dc:creator>Swulius, M. T.</dc:creator>
<dc:creator>Aich, S.</dc:creator>
<dc:creator>Mishra, M.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2017-11-18</dc:date>
<dc:identifier>doi:10.1101/194910</dc:identifier>
<dc:title><![CDATA[Coarse-grained simulations of actomyosin rings point to a nodeless model involving both unipolar and bipolar myosins]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/195685v1?rss=1">
<title>
<![CDATA[
In vivo structures of the Helicobacter pylori cag type IV secretion system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/195685v1?rss=1</link>
<description><![CDATA[
The bacterial type IV secretion system (T4SS) is a versatile nanomachine that translocates diverse effector molecules between microbes and into eukaryotic cells. Using electron cryotomography, here we reveal the molecular architecture of the cancer-associated Helicobacter pylori cag T4SS. Although most components are unique to H. pylori, the cag T4SS exhibits remarkable architectural similarity to previously studied T4SSs. When H. pylori encounters host cells, however, the bacterium elaborates rigid, membranous tubes perforated by lateral ports. Dense, pilus-like rod structures extending from the inner membrane were also observed. We propose that the membrane tubes assemble out of the T4SS and are the delivery system for cag T4SS cargo. These studies reveal the architecture of a dynamic molecular machine that evolved to function in the human gastric niche.
]]></description>
<dc:creator>Chang, Y.-W.</dc:creator>
<dc:creator>Shaffer, C. L.</dc:creator>
<dc:creator>Rettberg, L. A.</dc:creator>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2017-09-28</dc:date>
<dc:identifier>doi:10.1101/195685</dc:identifier>
<dc:title><![CDATA[In vivo structures of the Helicobacter pylori cag type IV secretion system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-09-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/198598v1?rss=1">
<title>
<![CDATA[
Gene expression dynamics and inter-tissue recognition mechanisms during tissue fusion at the Arabidopsis graft junction 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/198598v1?rss=1</link>
<description><![CDATA[
The ability for cut tissues to join together and form a chimeric organism is a remarkable property of many plants, however, grafting is poorly characterized at the molecular level. To better understand this process we monitored genome-wide temporal and spatial gene expression changes in grafted Arabidopsis thaliana hypocotyls. Tissues above and below the graft rapidly developed an asymmetry such that many genes were more highly expressed on one side than the other. This asymmetry correlated with sugar responsive genes and we observed an accumulation of starch above the graft that decreased along with asymmetry once the sugar-transporting vascular tissues reconnected. Despite the initial starvation response below the graft, many genes associated with vascular formation were rapidly activated in grafted tissues but not in cut and separated tissues indicating that a recognition mechanism activated that was independent of functional vascular connections. Auxin which is transported cell-to-cell, had a rapidly elevated response that was symmetric, suggesting that auxin was perceived by the root within hours of tissue attachment to activate the vascular regeneration process. A subset of genes were expressed only in grafted tissues, indicating that wound healing proceeded via different mechanisms depending on the presence or absence of adjoining tissues. Such a recognition process could have broader relevance for tissue regeneration, inter-tissue communication and tissue fusion events.
]]></description>
<dc:creator>Melnyk, C. W.</dc:creator>
<dc:creator>Gabel, A.</dc:creator>
<dc:creator>Hardcastle, T. J.</dc:creator>
<dc:creator>Robinson, S.</dc:creator>
<dc:creator>Miyashima, S.</dc:creator>
<dc:creator>Grosse, I.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:date>2017-10-05</dc:date>
<dc:identifier>doi:10.1101/198598</dc:identifier>
<dc:title><![CDATA[Gene expression dynamics and inter-tissue recognition mechanisms during tissue fusion at the Arabidopsis graft junction]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/198945v1?rss=1">
<title>
<![CDATA[
Hox-logic of preadaptations for social insect symbiosis in rove beetles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/198945v1?rss=1</link>
<description><![CDATA[
How symbiotic lifestyles evolve from free-living ecologies is poorly understood. In Metazoas largest family, Staphylinidae (rove beetles), numerous lineages have evolved obligate behavioral symbioses with ants or termites. Widespread convergence of this lifestyle is thought to stem from a novel, chemically defended body plan that enables free-living species to infiltrate colonies and undergo extreme evolutionary specialization. Here we show how this innovative body plan evolved, via new Hox functions in staphylinids that remodeled the coleopteran groundplan. Using a model staphylinid, Dalotia coriaria, we reveal the Hox basis for changes in thoracic appendage morphology that shortened the beetle elytron and left the abdomen physically unprotected, selecting for an abdominal defense gland that was likely key to unlocking ant and termite societies. We present evidence that the gland evolved through a novel, combinatorial role of the abdominal Hox proteins AbdA and AbdB. These proteins function together to specify distinct gland cell types in neighboring segmental compartments, each cell type synthesizing a different class of compound--irritant, ester and solvent. Only when secreted together do these compounds constitute a bioactive secretion, providing an example of emergent chemical functionality that arises from synergy between individual gland cell types. Hox-controlled specification of glandular diversity implies a modularity in compound biosynthesis that likely catalyzed the evolvability of rove beetle chemistry, including the capacity of symbiotic taxa to produce potent compounds for host deception. This study reveals how Hox-controlled body axis modifications predispose a major animal to convergently evolve into symbionts.
]]></description>
<dc:creator>Parker, J.</dc:creator>
<dc:creator>Eldredge, K. T.</dc:creator>
<dc:creator>Thomas, I.</dc:creator>
<dc:creator>Coleman, R.</dc:creator>
<dc:creator>Davis, S.</dc:creator>
<dc:date>2017-10-05</dc:date>
<dc:identifier>doi:10.1101/198945</dc:identifier>
<dc:title><![CDATA[Hox-logic of preadaptations for social insect symbiosis in rove beetles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/198978v1?rss=1">
<title>
<![CDATA[
Cell Cycle Control by Nuclear Sequestration of CDC20 and CDH1 mRNA in Plant Stem Cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/198978v1?rss=1</link>
<description><![CDATA[
In eukaryotic cells, most RNA molecules are exported into the cytoplasm after being transcribed in the nucleus. Long noncoding RNAs (lncRNAs) have been found to reside and function primarily inside the nucleus, but nuclear localization of protein-coding messenger RNAs (mRNAs) has been considered rare in both animals and plants. Here we show that two mRNAs, transcribed from the CDC20 and CCS52B (plant orthologue of CDH1) genes, are specifically sequestered inside the nucleus during the cell cycle. CDC20 and CDH1 both function as coactivators of the anaphase-promoting complex or cyclosome (APC/C) E3 ligase to trigger cyclin B (C YCB) destruction. In the Arabidopsis thaliana shoot apical meristem (SAM), we find CDC20 and CCS52B are co-expressed with CYCBs in mitotic cells. CYCB transcripts can be exported and translated, whereas CDC20 and CCS52B mRNAs are strictly confined to the nucleus at prophase and the cognate proteins are not translated until the redistribution of the mRNAs to the cytoplasm after nuclear envelope breakdown (NEBD) at prometaphase. The 5 untranslated region (UTR) is necessary and sufficient for CDC20 mRNA nuclear localization as well as protein translation. Mitotic enrichment of CDC20 and CCS52B transcripts enables the timely and rapid activation of APC/C, while their nuclear sequestration at prophase appears to protect cyclins from precocious degradation.
]]></description>
<dc:creator>Yang, W.</dc:creator>
<dc:creator>Wightman, R.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:date>2017-10-05</dc:date>
<dc:identifier>doi:10.1101/198978</dc:identifier>
<dc:title><![CDATA[Cell Cycle Control by Nuclear Sequestration of CDC20 and CDH1 mRNA in Plant Stem Cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/200758v1?rss=1">
<title>
<![CDATA[
A Deep Recurrent Neural Network Discovers Complex Biological Rules to Decipher RNA Protein-Coding Potential 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/200758v1?rss=1</link>
<description><![CDATA[
The current deluge of newly identified RNA transcripts presents a singular opportunity for improved assessment of coding potential, a cornerstone of genome annotation, and for machine-driven discovery of biological knowledge. While traditional, feature-based methods for RNA classification are limited by current scientific knowledge, deep learning methods can independently discover complex biological rules in the data de novo. We trained a gated recurrent neural network (RNN) on human messenger RNA (mRNA) and long noncoding RNA (lncRNA) sequences. Our model, mRNA RNN (mRNN), surpasses state-of-the-art methods at predicting protein-coding potential. To understand what mRNN learned, we probed the network and uncovered several context-sensitive codons highly predictive of coding potential. Our results suggest that gated RNNs can learn complex and long-range patterns in full-length human transcripts, making them ideal for performing a wide range of difficult classification tasks and, most importantly, for harvesting new biological insights from the rising flood of sequencing data.
]]></description>
<dc:creator>Hill, S. T.</dc:creator>
<dc:creator>Kuintzle, R. C.</dc:creator>
<dc:creator>Teegarden, A.</dc:creator>
<dc:creator>Merrill, E.</dc:creator>
<dc:creator>Danaee, P.</dc:creator>
<dc:creator>Hendrix, D. A.</dc:creator>
<dc:date>2017-10-13</dc:date>
<dc:identifier>doi:10.1101/200758</dc:identifier>
<dc:title><![CDATA[A Deep Recurrent Neural Network Discovers Complex Biological Rules to Decipher RNA Protein-Coding Potential]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/201517v1?rss=1">
<title>
<![CDATA[
Accurate design of translational output by a neural network model of ribosome distribution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/201517v1?rss=1</link>
<description><![CDATA[
Synonymous codon choice can have dramatic effects on ribosome speed, RNA stability, and protein expression. Ribosome profiling experiments have underscored that ribosomes do not move uniformly along mRNAs, exposing a need for models of coding sequences that capture the full range of empirically observed variation. We present a method, Ixnos, that models this variation in translation elongation using a feedforward neural network to predict the translation elongation rate at each codon as a function of its sequence neighborhood. Our approach revealed sequence features affecting translation elongation and quantified the impact of large technical biases in ribosome profiling. We applied our model to design synonymous variants of a fluorescent protein spanning the range of possible translation speeds predicted with our model. We found that levels of the fluorescent protein in yeast closely tracked the predicted translation speeds across their full range. We therefore demonstrate that our model captures information determining translation dynamics in vivo, and that control of translation elongation alone is sufficient to produce large, quantitative differences in protein output.
]]></description>
<dc:creator>Tunney, R. J.</dc:creator>
<dc:creator>McGlincy, N. J.</dc:creator>
<dc:creator>Graham, M. E.</dc:creator>
<dc:creator>Naddaf, N.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Lareau, L.</dc:creator>
<dc:date>2017-10-11</dc:date>
<dc:identifier>doi:10.1101/201517</dc:identifier>
<dc:title><![CDATA[Accurate design of translational output by a neural network model of ribosome distribution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2019.12.12.872085v1?rss=1">
<title>
<![CDATA[
Extracellular DNA promotes efficient extracellular electron transfer by pyocyanin in Pseudomonas aeruginosa biofilms 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2019.12.12.872085v1?rss=1</link>
<description><![CDATA[
Extracellular electron transfer (EET), the process whereby cells access electron acceptors or donors that reside many cell lengths away, enables metabolic activity by microorganisms, particularly under oxidant-limited conditions that occur in multicellular bacterial biofilms. Although different mechanisms underpin this process in select organisms, a widespread strategy involves extracellular electron shuttles, redox-active metabolites that are secreted and recycled by diverse bacteria. How these shuttles catalyze electron transfer within biofilms without being lost to the environment has been a long-standing question. Here, we show that phenazine electron shuttles mediate efficient EET through interactions with extracellular DNA (eDNA) in Pseudomonas aeruginosa biofilms, which are important in nature and disease. Retention of pyocyanin (PYO) and phenazine carboxamide in the biofilm matrix is facilitated by binding to eDNA. In vitro, different phenazines can exchange electrons in the presence or absence of DNA and phenazines can participate directly in redox reactions through DNA; the biofilm eDNA can also support rapid electron transfer between redox active intercalators. Electrochemical measurements of biofilms indicate that retained PYO supports an efficient redox cycle with rapid EET and slow loss from the biofilm. Together, these results establish that eDNA facilitates phenazine metabolic processes in P. aeruginosa biofilms, suggesting a model for how extracellular electron shuttles achieve retention and efficient EET in biofilms.
]]></description>
<dc:creator>Saunders, S. H.</dc:creator>
<dc:creator>Tse, E. C. M.</dc:creator>
<dc:creator>Yates, M. D.</dc:creator>
<dc:creator>Jimenez Otero, F.</dc:creator>
<dc:creator>Trammell, S. A.</dc:creator>
<dc:creator>Stemp, E. D. A.</dc:creator>
<dc:creator>Barton, J. K.</dc:creator>
<dc:creator>Tender, L. M.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2019-12-12</dc:date>
<dc:identifier>doi:10.1101/2019.12.12.872085</dc:identifier>
<dc:title><![CDATA[Extracellular DNA promotes efficient extracellular electron transfer by pyocyanin in Pseudomonas aeruginosa biofilms]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2019.12.16.878652v1?rss=1">
<title>
<![CDATA[
Contrast-Enhanced, Molecular Imaging of Vascular Inflammation in the Mouse Model by Simultaneous PET/MRI 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2019.12.16.878652v1?rss=1</link>
<description><![CDATA[
Despite advances in diagnosis and management, cardiovascular diseases (CVDs) remain the leading cause of death in the US. Atherosclerosis is the most common form of CVD and the vulnerability of atherosclerotic plaques to rupture is a primary determinant for risk of catastrophic ischemic events. Current imaging of atherosclerotic disease focuses on assessing plaque size and the degree of luminal stenosis, which are not good predictors of plaque stability. Functional methods to identify biomarkers of inflammation in plaques could facilitate assessment of plaque instability to allow early intervention. In this study, we validate the use of a purpose-built, magnetic resonance imaging (MRI)-compatible positron emission tomography (PET) insert for multimodal, molecular imaging of vulnerable plaques in mice. We illustrate the application of PET to screen for inflamed regions to guide the application of MRI. Molecular MRI visualizes regions of vascular inflammation and is coupled with anatomical MRI to generate detailed maps of the inflammatory marker within the context of an individual vessel. As a testbed for this imaging methodology, we developed a multimodal, iron oxide nanoparticle (NP) targeting vascular cell adhesion molecule-1 (VCAM-1) for simultaneous PET/MRI of vascular inflammation performed on a mouse carotid ligation model. In vitro cell studies confirmed that the NPs are not cytotoxic to liver cells. In vivo simultaneous PET/MRI imaging identified regions of inflammation. Three-dimensional rendering of the MRI data facilitated high-resolution visualization of patterns of inflammation along the injured vessel. Histology validated the co-localization of the NPs with VCAM-1 expression at sites of induced inflammation. The results of this work validate the utility of the simultaneous PET/MR insert as a research tool for small animals and lays groundwork to further advance the potential clinical utility of integrated imaging systems.
]]></description>
<dc:creator>Du, S.</dc:creator>
<dc:creator>Ng, T.</dc:creator>
<dc:creator>House, A.</dc:creator>
<dc:creator>Tang, T.</dc:creator>
<dc:creator>Zheng, L.</dc:creator>
<dc:creator>Tu, C.</dc:creator>
<dc:creator>Peake, J.</dc:creator>
<dc:creator>Espiritu, I.</dc:creator>
<dc:creator>Ma, K.-L.</dc:creator>
<dc:creator>Pinkerton, K.</dc:creator>
<dc:creator>Jacobs, R.</dc:creator>
<dc:creator>Louie, A.</dc:creator>
<dc:date>2019-12-17</dc:date>
<dc:identifier>doi:10.1101/2019.12.16.878652</dc:identifier>
<dc:title><![CDATA[Contrast-Enhanced, Molecular Imaging of Vascular Inflammation in the Mouse Model by Simultaneous PET/MRI]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2019.12.19.878462v1?rss=1">
<title>
<![CDATA[
Physiological Adaptability and Parametric Versatility in a Simple Genetic Circuit 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2019.12.19.878462v1?rss=1</link>
<description><![CDATA[
The intimate relationship between the environment and cellular growth rate has remained a major topic of inquiry in bacterial physiology for over a century. Now, as it becomes possible to understand how the growth rate dictates the wholesale reorganization of the intracellular molecular composition, we can interrogate the biophysical principles underlying this adaptive response. Regulation of gene expression drives this adaptation, with changes in growth rate tied to the activation or repression of genes covering enormous swaths of the genome. Here, we dissect how physiological perturbations alter the expression of a circuit which has been extensively characterized in a single physiological state. Given a complete thermodynamic model, we map changes in physiology directly to the biophysical parameters which define the expression. Controlling the growth rate via modulating the available carbon source or growth temperature, we measure the level of gene expression from a LacI-regulated promoter where the LacI copy number is directly measured in each condition, permitting parameter-free prediction of the expression level. The transcriptional output of this circuit is remarkably robust, with expression of the repressor being largely insensitive to the growth rate. The predicted gene expression quantitatively captures the observations under different carbon conditions, indicating that the bio-physical parameters are indifferent to the physiology. Interestingly, temperature controls the expression level in ways that are inconsistent with the prediction, revealing temperature-dependent effects that challenge current models. This work exposes the strengths and weaknesses of thermodynamic models in fluctuating environments, posing novel challenges and utility in studying physiological adaptation.

SignificanceCells adapt to changing environmental conditions by repressing or activating gene expression from enormous fractions of their genome, drastically changing the molecular composition of the cell. This requires the concerted adaptation of transcription factors to the environmental signals, leading to binding or releasing of their cognate sequences. Here, we dissect a well characterized genetic circuit in a number of physiological states, make predictions of the response, and measure how the copy number of a regulator and its gene target are affected. We find the parameters defining the regulators behavior are remarkably robust to changes in the nutrient availability, but are susceptible to temperature changes. We quantitatively explore these two effects and discuss how they challenge current models of transcriptional regulation.
]]></description>
<dc:creator>Chure, G.</dc:creator>
<dc:creator>Kaczmarek, Z. A.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2019-12-19</dc:date>
<dc:identifier>doi:10.1101/2019.12.19.878462</dc:identifier>
<dc:title><![CDATA[Physiological Adaptability and Parametric Versatility in a Simple Genetic Circuit]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2019.12.19.883173v1?rss=1">
<title>
<![CDATA[
No strong evidence that social network index is associated with gray matter volume from a data-driven investigation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2019.12.19.883173v1?rss=1</link>
<description><![CDATA[
Recent studies in adult humans have reported correlations between individual differences in peoples Social Network Index (SNI) and gray matter volume (GMV) across multiple regions of the brain. However, the cortical and subcortical loci identified are inconsistent across studies. These discrepancies might arise because different regions of interest were hypothesized and tested in different studies without controlling for multiple comparisons, and/or from insufficiently large sample sizes to fully protect against statistically unreliable findings. Here we took a data-driven approach in a pre-registered study to comprehensively investigate the relationship between SNI and GMV in every cortical and subcortical region, using three predictive modeling frameworks. We also included psychological predictors such as cognitive and emotional intelligence, personality, and mood. In a sample of healthy adults (n = 92), neither multivariate frameworks (e.g., ridge regression with cross-validation) nor univariate frameworks (e.g., univariate linear regression with cross-validation) showed a significant association between SNI and any GMV or psychological feature after multiple comparison corrections (all R-squared values [&le;] 0.1). These results emphasize the importance of large sample sizes and hypothesis-driven studies to derive statistically reliable conclusions, and suggest that future meta-analyses will be needed to more accurately estimate the true effect sizes in this field.
]]></description>
<dc:creator>Lin, C.</dc:creator>
<dc:creator>Keles, U.</dc:creator>
<dc:creator>Tyszka, M. J.</dc:creator>
<dc:creator>Gallo, M.</dc:creator>
<dc:creator>Paul, L.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:date>2019-12-27</dc:date>
<dc:identifier>doi:10.1101/2019.12.19.883173</dc:identifier>
<dc:title><![CDATA[No strong evidence that social network index is associated with gray matter volume from a data-driven investigation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2019.12.21.885830v1?rss=1">
<title>
<![CDATA[
Dissecting the regulatory activity and key sequence elements of loci with exceptional numbers of transcription factor associations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2019.12.21.885830v1?rss=1</link>
<description><![CDATA[
DNA associated proteins (DAPs) classically regulate gene expression by binding to regulatory loci such as enhancers or promoters. As expanding catalogs of genome-wide DAP binding maps reveal thousands of loci that, unlike the majority of conventional enhancers and promoters, associate with dozens of different DAPs with apparently little regard for motif preference, an understanding of DAP association and coordination at such regulatory loci is essential to deciphering how these regions contribute to normal development and disease. In this study, we aggregated publicly available ChIP-seq data from 469 human DAPs assayed in three cell lines and integrated these data with an orthogonal dataset of 352 non-redundant, in vitro-derived motifs mapped to the genome within DNase hypersensitivity footprints in an effort to characterize regions of the genome that have exceptionally high numbers of DAP associations. We subsequently performed a massively parallel mutagenesis assay to search for sequence elements driving transcriptional activity at such loci and explored plausible biological mechanisms underlying their formation. We establish a generalizable definition for High Occupancy Target (HOT) loci and identify putative driver DAP motifs in HEPG2 cells, including HNF4A, SP1, SP5, and ETV4, that are highly prevalent and exhibit sequence conservation at HOT loci. The number of different DAPs associated with an element is positively associated with evidence of regulatory activity and, by systematically mutating 245 HOT loci, we localized regulatory activity to a central core region that depends on the motif sequences of our previously nominated driver DAPs. In sum, this work leverages the increasingly large number of DAP motif and ChIP-seq data publicly available to explore how DAP associations contribute to genome-wide transcriptional regulation.
]]></description>
<dc:creator>Ramaker, R. C.</dc:creator>
<dc:creator>Hardigan, A. A.</dc:creator>
<dc:creator>Goh, S.-T.</dc:creator>
<dc:creator>Partridge, E. C.</dc:creator>
<dc:creator>Wold, B.</dc:creator>
<dc:creator>Cooper, S. J.</dc:creator>
<dc:creator>Myers, R. M.</dc:creator>
<dc:date>2019-12-23</dc:date>
<dc:identifier>doi:10.1101/2019.12.21.885830</dc:identifier>
<dc:title><![CDATA[Dissecting the regulatory activity and key sequence elements of loci with exceptional numbers of transcription factor associations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2019.12.23.887638v1?rss=1">
<title>
<![CDATA[
Plasma membrane damage removal by F-actin-mediated shedding from repurposed filopodia 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2019.12.23.887638v1?rss=1</link>
<description><![CDATA[
Repairing plasma membrane damage is vital to eukaryotic cell survival. Membrane shedding is thought to be key to this repair process, but a detailed view of how the process occurs is still missing. Here we used electron cryotomography to image the ultrastructural details of plasma membrane wound healing. We found that filopodia-like protrusions are built at damage sites, accompanied by retraction of neighboring filopodia, and that these repurposed protrusions act as scaffolds for membrane shedding. This suggests a new role for filopodia as reservoirs of membrane and actin for plasma membrane damage repair. Damage-induced shedding was dependent on F-actin dynamics and Myo1a, as well as Vps4B, an important component of the ESCRT machinery. Thus we find that damage shedding is more complex than current models of simple vesiculation from flat membrane domains. Rather, we observe structural similarities between damage-mediated shedding and constitutive shedding from enterocytes that argue for conservation of a general membrane shedding mechanism.
]]></description>
<dc:creator>Mageswaran, S. K.</dc:creator>
<dc:creator>Yang, W. Y.</dc:creator>
<dc:creator>Chakrabarty, Y.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2019-12-24</dc:date>
<dc:identifier>doi:10.1101/2019.12.23.887638</dc:identifier>
<dc:title><![CDATA[Plasma membrane damage removal by F-actin-mediated shedding from repurposed filopodia]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2019.12.23.887653v1?rss=1">
<title>
<![CDATA[
Sequestration of Methane by Symbiotic Deep-Sea Annelids: Ancient and Future Implications of Redefining the Seep Influence 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2019.12.23.887653v1?rss=1</link>
<description><![CDATA[
Deep-sea methane seeps are dynamic sources of greenhouse gas production and unique habitats supporting ocean biodiversity and productivity. Here, we demonstrate new animal-bacterial symbioses fueled by methane, between two undescribed species of annelid (a serpulid Laminatubus and sabellid Bispira) and distinct methane-oxidizing Methylococcales bacteria. Worm tissue {delta}13C of -44{per thousand} to -58{per thousand} suggested methane-fueled nutrition for both species and shipboard experiments revealed active assimilation of 13C-labelled CH4 into animal biomass, occurring via engulfment of methanotrophic bacteria across the host epidermal surface. These worms represent a new addition to the few animals known to intimately associate with methane-oxidizing bacteria, and further explain their enigmatic mass occurrence at 150-million-year-old fossil seeps. High-resolution seafloor surveys document significant coverage by these symbioses, beyond typical obligate seep fauna. These findings uncover novel consumers of methane in the deep-sea, and by expanding the known spatial extent of methane seeps, may have important implications for deep-sea conservation.
]]></description>
<dc:creator>Goffredi, S. K.</dc:creator>
<dc:creator>Tilic, E.</dc:creator>
<dc:creator>Mullin, S. W.</dc:creator>
<dc:creator>Dawson, K. S.</dc:creator>
<dc:creator>Keller, A.</dc:creator>
<dc:creator>Lee, R.</dc:creator>
<dc:creator>Wu, F.</dc:creator>
<dc:creator>Levin, L. A.</dc:creator>
<dc:creator>Rouse, G. W.</dc:creator>
<dc:creator>Cordes, E.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2019-12-27</dc:date>
<dc:identifier>doi:10.1101/2019.12.23.887653</dc:identifier>
<dc:title><![CDATA[Sequestration of Methane by Symbiotic Deep-Sea Annelids: Ancient and Future Implications of Redefining the Seep Influence]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2019.12.27.889402v1?rss=1">
<title>
<![CDATA[
Neuropeptide VF neurons promote sleep via the serotonergic raphe 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2019.12.27.889402v1?rss=1</link>
<description><![CDATA[
Although several sleep-regulating neurons have been identified, little is known about how they interact with each other for sleep/wake control. We previously identified neuropeptide VF (NPVF) and the hypothalamic neurons that produce it as a sleep-promoting system (Lee et al., 2017). Here we use zebrafish to describe a neural circuit in which neuropeptide VF (npvf)-expressing neurons control sleep via the serotonergic raphe nuclei (RN), a hindbrain structure that promotes sleep in both diurnal zebrafish and nocturnal mice. Using genetic labeling and calcium imaging, we show that npvf-expressing neurons innervate and activate serotonergic RN neurons. We additionally demonstrate that optogenetic stimulation of npvf-expressing neurons induces sleep in a manner that requires NPVF and is abolished when the RN are ablated or lack serotonin. Finally, genetic epistasis demonstrates that NPVF acts upstream of serotonin in the RN to maintain normal sleep levels. These findings reveal a novel hypothalamic-hindbrain circuit for sleep/wake control.
]]></description>
<dc:creator>Lee, D. A.</dc:creator>
<dc:creator>Oikonomou, G.</dc:creator>
<dc:creator>Cammidge, T.</dc:creator>
<dc:creator>Hong, Y.</dc:creator>
<dc:creator>Prober, D. A.</dc:creator>
<dc:date>2019-12-28</dc:date>
<dc:identifier>doi:10.1101/2019.12.27.889402</dc:identifier>
<dc:title><![CDATA[Neuropeptide VF neurons promote sleep via the serotonergic raphe]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2019.12.30.890087v1?rss=1">
<title>
<![CDATA[
Designing signaling environments to steer transcriptional diversity in neural progenitor cell populations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2019.12.30.890087v1?rss=1</link>
<description><![CDATA[
Stem and progenitor populations within developing embryos are diverse, composed of different subpopulations of precursor cells with varying developmental potential. How these different subpopulations are coordinately regulated by their signaling environments is not well understood. In this paper we develop a framework for controlling progenitor population structure in cell culture using high-throughput single cell mRNA-seq and computational analysis. We find that the natural transcriptional diversity of neural stem cell populations from the developing mouse brain collapses during in vitro culture. Cell populations are depleted of committed neuroblast progenitors and become dominated by a single pre-astrocytic cell population. By analyzing the response of neural stem cell populations to forty combinatorial signaling conditions, we demonstrate that signaling environments can restructure cell populations by modulating the relative abundance of pre-astrocytic and pre-neuronal subpopulations according to a simple log-linear model. Our work demonstrates that single-cell RNA-seq can be applied to learn how to modulate the diversity of stem cell populations, providing a new strategy for population-level stem cell control.

HighlightsO_LINatural progenitor diversity in the brain collapses during in vitro culture to a single progenitor type
C_LIO_LILoss of progenitor diversity alters fate potential of cells during differentiation
C_LIO_LILarge scale single-cell signaling screen identifies signals that reshape population structure towards neuronal cell types
C_LIO_LISignals regulate population structure according to a simple log-linear model
C_LI

GRAPHICAL ABSTRACT

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=89 SRC="FIGDIR/small/890087v3_ufig1.gif" ALT="Figure 1">
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]]></description>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Park, J. H.</dc:creator>
<dc:creator>Tsou, T.</dc:creator>
<dc:creator>Rivaud, P.</dc:creator>
<dc:date>2019-12-31</dc:date>
<dc:identifier>doi:10.1101/2019.12.30.890087</dc:identifier>
<dc:title><![CDATA[Designing signaling environments to steer transcriptional diversity in neural progenitor cell populations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2019.12.31.892067v1?rss=1">
<title>
<![CDATA[
Dual roles of the Sterol Recognition Region in Hedgehog protein modification 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2019.12.31.892067v1?rss=1</link>
<description><![CDATA[
Nature provides a number of mechanisms to encode dynamic information in biomolecules. In metazoans, there exist rare chemical modifications that occur through entirely unique mechanistic regimes. One such example occurs in the Hedgehog (Hh) morphogens, proteins singular across all domains of life for the nature of their covalent ligation to cholesterol. The isoform- and context-specific efficiency of the ligation reaction has profound impact on the activity of Hh morphogens and represents an unexplored aspect of Hh ligand-dependent cancers. To elucidate the chemical mechanism of this modification, we have defined roles of the uncharacterized sterol recognition region (SRR) in Hh proteins. We use a combination of sequence conservation, directed mutagenesis, and biochemical assays to specify residues of the SRR that are responsible for cellular and biochemical processes in Hh cholesterolysis. Our investigations offer the first functional template of this region, providing opportunities to identify parallel reactivity in nature and revealing new mechanisms that can be exploited as tools in chemical biology.
]]></description>
<dc:creator>Purohit, R.</dc:creator>
<dc:creator>Peng, D. S.</dc:creator>
<dc:creator>Vielmas, E.</dc:creator>
<dc:creator>Ondrus, A. E.</dc:creator>
<dc:date>2020-01-01</dc:date>
<dc:identifier>doi:10.1101/2019.12.31.892067</dc:identifier>
<dc:title><![CDATA[Dual roles of the Sterol Recognition Region in Hedgehog protein modification]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-01-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.01.07.897827v1?rss=1">
<title>
<![CDATA[
Receptor compaction and GTPase movements drive cotranslational protein translocation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.01.07.897827v1?rss=1</link>
<description><![CDATA[
Signal recognition particle (SRP) is a universally conserved targeting machine that couples the synthesis of ~30% of the proteome to their proper membrane localization1,2. In eukaryotic cells, SRP recognizes translating ribosomes bearing hydrophobic signal sequences and, through interaction with SRP receptor (SR), delivers them to the Sec61p translocase on the endoplasmic reticulum (ER) membrane1,2. How SRP ensures efficient and productive initiation of protein translocation at the ER is not well understood. Here, single molecule fluorescence spectroscopy demonstrates that cargo-loaded SRP induces a global compaction of SR, driving a >90 [A] movement of the SRP*SR GTPase complex from the vicinity of the ribosome exit, where it initially assembles, to the distal site of SRP. These rearrangements bring translating ribosomes near the membrane, expose conserved Sec61p docking sites on the ribosome and weaken SRPs interaction with the signal sequence on the nascent polypeptide, thus priming the translating ribosome for engaging the translocation machinery. Disruption of these rearrangements severely impairs cotranslational protein translocation and is the cause of failure in an SRP54 mutant linked to severe congenital neutropenia. Our results demonstrate that multiple largescale molecular motions in the SRP*SR complex are required to drive the transition from protein targeting to translocation; these post-targeting rearrangements provide potential new points for biological regulation as well as disease intervention.
]]></description>
<dc:creator>Lee, J. H.</dc:creator>
<dc:creator>Chung, S.</dc:creator>
<dc:creator>Hwang Fu, Y.-H.</dc:creator>
<dc:creator>Qian, R.</dc:creator>
<dc:creator>Sun, X.</dc:creator>
<dc:creator>Weiss, S.</dc:creator>
<dc:creator>Shan, S.-o.</dc:creator>
<dc:date>2020-01-08</dc:date>
<dc:identifier>doi:10.1101/2020.01.07.897827</dc:identifier>
<dc:title><![CDATA[Receptor compaction and GTPase movements drive cotranslational protein translocation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-01-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.01.18.911388v1?rss=1">
<title>
<![CDATA[
Construction, characterization, and immunization of nanoparticles that display a diverse array of influenza HA trimers 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.01.18.911388v1?rss=1</link>
<description><![CDATA[
Current influenza vaccines do not elicit broadly protective immune responses against multiple strains. New strategies to focus the humoral immune response to conserved regions on influenza antigens are therefore required for recognition by broadly neutralizing antibodies. It has been suggested that B-cells with receptors that recognize conserved epitopes would be preferentially stimulated through avidity effects by mosaic particles presenting multiple forms of a variable antigen. We adapted SpyCatcher-based platforms, AP205 virus-like particles (VLPs) and mi3 nanoparticles (NPs), to covalently co-display SpyTagged hemagglutinin (HA) trimers from group 1 and group 2 influenza A strains. Here we show successful homotypic and heterotypic conjugation of up to 8 different HA trimers to both VLPs and NPs. We characterized the HA-VLPs and HA-NPs by cryo-electron tomography to derive the average number of conjugated HAs and their separation distances on particles, and compared immunizations of mosaic and homotypic particles in wild-type mice. Both types of HA particles elicited strong antibody responses, but the mosaic particles did not consistently elicit broader immune responses than mixtures of homotypic particles. We conclude that covalent attachment of HAs from currently-circulating influenza strains represents a viable alternative to current annual influenza vaccine strategies, but in the absence of further modifications, is unlikely to represent a method for making a universal influenza vaccine.
]]></description>
<dc:creator>Cohen, A. A.</dc:creator>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Gnanapragasam, P.</dc:creator>
<dc:creator>Ou, S.</dc:creator>
<dc:creator>Dam, K.-M.</dc:creator>
<dc:creator>Wang, H.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2020-01-19</dc:date>
<dc:identifier>doi:10.1101/2020.01.18.911388</dc:identifier>
<dc:title><![CDATA[Construction, characterization, and immunization of nanoparticles that display a diverse array of influenza HA trimers]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-01-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.01.22.914705v1?rss=1">
<title>
<![CDATA[
Quantitative microbiome profiling in lumenal and tissue samples with broad coverage and dynamic range via a single-step 16S rRNA gene DNA copy quantification and amplicon barcoding 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.01.22.914705v1?rss=1</link>
<description><![CDATA[
Current methods for detecting, accurately quantifying, and profiling complex microbial communities based on the microbial 16S rRNA marker genes are limited by a number of factors, including inconsistent extraction of microbial nucleic acids, amplification interference from contaminants and host DNA, different coverage of PCR primers utilized for quantification and sequencing, and potentially biases in PCR amplification rates among microbial taxa during amplicon barcoding. Here, we describe a single-step method that enables the quantification of microbial 16S rRNA gene DNA copies with wide dynamic range and broad microbial diversity, and simultaneous amplicon barcoding for quantitative 16S rRNA gene amplicon profiling of microbiota. The method is suitable for a variety of sample types and is robust in samples with low microbial abundance, including samples containing high levels of host mammalian DNA, as is common in human clinical samples. We demonstrate that our modification to the Earth Microbiome Project (EMP) V4 16S rRNA gene primers expands their microbial coverage while dramatically reducing non-specific mammalian mitochondrial DNA amplification, thus achieving wide dynamic range in microbial quantification and broad coverage for capturing high microbial diversity in samples with or without high host DNA background. The approach relies only on broadly available hardware (real-time PCR instruments) and standard reagents utilized for conventional 16S rRNA gene amplicon library preparation both of which make it amenable for immediate and widespread adoption. Simultaneous 16S rRNA gene DNA copy quantification and amplicon barcoding for multiplexed next-generation sequencing from the same analyzed sample, performed in a combined workflow, reduces the amount of sample needed and reduces time and reagent costs. Additionally, we demonstrate that using our modified 16S rRNA gene primers in a digital PCR (dPCR) format enables precise and exact microbial quantification in samples with very high host DNA background levels without the need for quantification standards. Potential future applications of this approach include: (1) quantitative microbiome profiling in human and animal microbiome research; (2) detection of monoinfections and profiling of polymicrobial infections in tissues, stool, and bodily fluids in human and veterinary medicine; (3) environmental sample analyses (e.g., soil and water); and (4) broad-coverage detection of microbial food contamination in products high in mammalian DNA, such as meat products. We predict that utilization of this approach primarily for quantitative microbiome profiling will be invaluable to microbiome studies, which have historically been limited to analysis of relative abundances of microbes.
]]></description>
<dc:creator>Bogatyrev, S. R.</dc:creator>
<dc:creator>Ismagilov, R. F.</dc:creator>
<dc:date>2020-01-22</dc:date>
<dc:identifier>doi:10.1101/2020.01.22.914705</dc:identifier>
<dc:title><![CDATA[Quantitative microbiome profiling in lumenal and tissue samples with broad coverage and dynamic range via a single-step 16S rRNA gene DNA copy quantification and amplicon barcoding]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-01-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.01.22.915199v1?rss=1">
<title>
<![CDATA[
Cancer-associated HIF-2α impacts trunk neural crest stemness 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.01.22.915199v1?rss=1</link>
<description><![CDATA[
The neural crest is a stem cell population that gives rise to sympathetic ganglia, the cell type of origin of neuroblastoma. Hypoxia Inducible Factor (HIF)-2 is associated with high risk neuroblastoma, however, little is known about its role in normal neural crest development. To address this important question, here we show that HIF-2 is expressed in trunk neural crest cells of human, murine and avian embryos. Modulating HIF-2 in vivo not only causes developmental delays but also induces proliferation and stemness of neural crest cells while altering the number of cells migrating ventrally to sympathoadrenal sites. Transcriptome changes after loss of HIF-2 reflect the in vivo phenotype. The results suggest that expression levels of HIF-2 must be strictly controlled and abnormal levels increase stemness and may promote metastasis. Our findings help elucidate the role of HIF-2 during normal development with implications also in tumor initiation at the onset of neuroblastoma.
]]></description>
<dc:creator>Mohlin, S.</dc:creator>
<dc:creator>Persson, C. U.</dc:creator>
<dc:creator>Fredlund, E.</dc:creator>
<dc:creator>Monni, E.</dc:creator>
<dc:creator>Lindvall, J. M.</dc:creator>
<dc:creator>Kokaia, Z.</dc:creator>
<dc:creator>Hammarlund, E.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:date>2020-01-23</dc:date>
<dc:identifier>doi:10.1101/2020.01.22.915199</dc:identifier>
<dc:title><![CDATA[Cancer-associated HIF-2α impacts trunk neural crest stemness]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-01-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.01.27.921734v1?rss=1">
<title>
<![CDATA[
Theoretical Design of Paradoxical Signaling-Based Synthetic Population Control Circuit in E. coli 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.01.27.921734v1?rss=1</link>
<description><![CDATA[
We have developed a mathematical framework to analyze the cooperative control of cell population homeostasis via paradoxical signaling in synthetic contexts. Paradoxical signaling functions through quorum sensing (where cells produce and release a chemical signal as a function of cell density). Precisely, the same quorum sensing signal provides both positive (proliferation) and negative (death) feedback in different signal concentration regimes. As a consequence, the relationship between intercellular quorum sensing signal concentration and net growth rate (cell proliferation minus death rates) can be non-monotonic. This relationship is a condition for robustness to certain cell mutational overgrowths and allows for increased stability in the presence of environmental perturbations. Here, we explore stability and robustness of a conceptualized synthetic circuit. Furthermore, we asses possible design principles that could exist among a subset of paradoxical circuit implementations. This analysis sparks the development a bio-molecular control theory to identify ideal underlying characteristics for paradoxical signaling control systems.
]]></description>
<dc:creator>Mayalu, M. N.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2020-01-28</dc:date>
<dc:identifier>doi:10.1101/2020.01.27.921734</dc:identifier>
<dc:title><![CDATA[Theoretical Design of Paradoxical Signaling-Based Synthetic Population Control Circuit in E. coli]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-01-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.01.30.926147v1?rss=1">
<title>
<![CDATA[
A Prokaryotic Membrane Sculpting BAR Domain Protein 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.01.30.926147v1?rss=1</link>
<description><![CDATA[
Bin/Amphiphysin/RVS (BAR) domain proteins belong to a superfamily of coiled-coil proteins influencing membrane curvature in eukaryotes and are associated with vesicle biogenesis, vesicle-mediated protein trafficking, and intracellular signaling. Here we report the first prokaryotic BAR domain protein, BdpA, from Shewanella oneidensis MR-1, known to produce redox-active membrane vesicles and micrometer-scale outer membrane extensions (OMEs). BdpA is required for uniform size distribution of membrane vesicles and scaffolding OMEs into a consistent diameter and curvature. Cryogenic transmission electron microscopy reveals a strain lacking BdpA produces lobed, disordered OMEs rather than membrane tubes produced by the wild type strain. Overexpression of BdpA promotes OME formation during conditions where they are less common. Heterologous expression results in OME production in Marinobacter atlanticus and Escherichia coli. Based on the ability of BdpA to alter membrane curvature in vivo, we propose that BdpA and its homologs comprise a newly identified class of prokaryotic BAR (P-BAR) domains.
]]></description>
<dc:creator>Phillips, D. A.</dc:creator>
<dc:creator>Zacharoff, L. A.</dc:creator>
<dc:creator>Hampton, C. M.</dc:creator>
<dc:creator>Chong, G. W.</dc:creator>
<dc:creator>Malanoski, A. P.</dc:creator>
<dc:creator>Metskas, L. A.</dc:creator>
<dc:creator>Xu, S.</dc:creator>
<dc:creator>Bird, L. J.</dc:creator>
<dc:creator>Eddie, B. J.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Drummy, L. F.</dc:creator>
<dc:creator>El-Naggar, M. Y.</dc:creator>
<dc:creator>Glaven, S. M.</dc:creator>
<dc:date>2020-01-31</dc:date>
<dc:identifier>doi:10.1101/2020.01.30.926147</dc:identifier>
<dc:title><![CDATA[A Prokaryotic Membrane Sculpting BAR Domain Protein]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-01-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.01.31.926899v1?rss=1">
<title>
<![CDATA[
A Combination of Two Human Monoclonal Antibodies Limits Fetal Damage by Zika Virus in Macaques 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.01.31.926899v1?rss=1</link>
<description><![CDATA[
Human infection by Zika virus (ZIKV) during pregnancy can lead to vertical transmission and fetal aberrations, including microcephaly. Prophylactic administration of antibodies can diminish or prevent ZIKV infection in animal models, but whether passive immunization can protect nonhuman primates and their fetuses during pregnancy has not been determined. Z004 and Z021 are neutralizing monoclonal antibodies to domain III of the envelope (EDIII) of ZIKV. Together the two antibodies protect nonpregnant macaques against infection even after Fc modifications to prevent antibody-dependent enhancement in vitro (ADE) and extend their half-lives. Here we report on prophylactic co-administration of the Fc-modified antibodies to pregnant rhesus macaques challenged 3 times with ZIKV during first and second trimester. The two antibodies did not entirely eliminate maternal viremia but limited vertical transmission protecting the fetus from neurologic damage. Thus, maternal passive immunization with two antibodies to EDIII can shield primate fetuses from the harmful effects of ZIKV.

Significance statementZika virus (ZIKV) infection during pregnancy can cause fetal abnormalities. Vaccines against ZIKV are under development, but because of potential safety concerns due to disease enhancing antibodies, and the time required by active immunization to induce protective antibodies, there is a need to explore alternative strategies. Recombinant monoclonal antibodies can be modified to prevent enhancement of infection, and thus could be an efficacious and safe alternative to vaccines to confer rapid protection. We show that prophylactic administration of two engineered antibodies, Z004 and Z021, to pregnant macaques partially protects against fetal neurologic damage and limits vertical transmission of ZIKV.
]]></description>
<dc:creator>Van Rompay, K. K. A.</dc:creator>
<dc:creator>Coffey, L. L.</dc:creator>
<dc:creator>Kapoor, T.</dc:creator>
<dc:creator>Gazumyan, A.</dc:creator>
<dc:creator>Keesler, R. I.</dc:creator>
<dc:creator>Jurado, A.</dc:creator>
<dc:creator>Peace, A.</dc:creator>
<dc:creator>Agudelo, M.</dc:creator>
<dc:creator>Watanabe, J.</dc:creator>
<dc:creator>Usachenko, J.</dc:creator>
<dc:creator>Singapuri, A.</dc:creator>
<dc:creator>Immareddy, R.</dc:creator>
<dc:creator>Ardeshir, A.</dc:creator>
<dc:creator>Stuart, J. B.</dc:creator>
<dc:creator>Bournazos, S.</dc:creator>
<dc:creator>Ravetch, J. V.</dc:creator>
<dc:creator>Balderes, P. J.</dc:creator>
<dc:creator>Lorenz, I. C.</dc:creator>
<dc:creator>Esswein, S. R.</dc:creator>
<dc:creator>Keeffe, J.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Wang, Q.</dc:creator>
<dc:creator>Rice, C. M.</dc:creator>
<dc:creator>MacDonald, M. R.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:creator>Robbiani, D. F.</dc:creator>
<dc:date>2020-02-02</dc:date>
<dc:identifier>doi:10.1101/2020.01.31.926899</dc:identifier>
<dc:title><![CDATA[A Combination of Two Human Monoclonal Antibodies Limits Fetal Damage by Zika Virus in Macaques]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.01.31.928689v1?rss=1">
<title>
<![CDATA[
Multiplexed characterization of rationally designed promoter architectures deconstructs combinatorial logic for IPTG-inducible systems 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.01.31.928689v1?rss=1</link>
<description><![CDATA[
A crucial step towards engineering biological systems is the ability to precisely tune the genetic response to environmental stimuli. In the case of Escherichia coli inducible promoters, our incomplete understanding of the relationship between sequence composition and gene expression hinders our ability to predictably control transcriptional responses. Here, we profile the expression dynamics of 8,269 rationally designed IPTG-inducible promoters that collectively explore the individual and combinatorial effects of RNA polymerase and LacI repressor binding site strengths. Using these data, we fit a statistical mechanics model that accurately models gene expression and reveals properties of theoretically optimal inducible promoters. Furthermore, we characterize three novel promoter architectures and show that repositioning binding sites within promoters influences the types of combinatorial effects observed between promoter elements. In total, this approach enables us to deconstruct relationships between inducible promoter elements and discover practical insights for engineering inducible promoters with desirable characteristics.
]]></description>
<dc:creator>Yu, T. C.</dc:creator>
<dc:creator>Liu, W. L.</dc:creator>
<dc:creator>Brinck, M. S.</dc:creator>
<dc:creator>Davis, J. E.</dc:creator>
<dc:creator>Shek, J.</dc:creator>
<dc:creator>Bower, G.</dc:creator>
<dc:creator>Einav, T.</dc:creator>
<dc:creator>Insigne, K. D.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:creator>Kosuri, S.</dc:creator>
<dc:creator>Urtecho, G.</dc:creator>
<dc:date>2020-02-02</dc:date>
<dc:identifier>doi:10.1101/2020.01.31.928689</dc:identifier>
<dc:title><![CDATA[Multiplexed characterization of rationally designed promoter architectures deconstructs combinatorial logic for IPTG-inducible systems]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.05.936039v1?rss=1">
<title>
<![CDATA[
Instant FLIM enables 4D in vivo lifetime imaging of intact brains 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.05.936039v1?rss=1</link>
<description><![CDATA[
Traditional fluorescence microscopy is blind to molecular microenvironment information that is present in fluorescence lifetime, which can be measured by fluorescence lifetime imaging microscopy (FLIM). However, existing FLIM techniques are typically slow to acquire and process lifetime images, difficult to implement, and expensive. Here, we present instant FLIM, an analog signal processing method that allows real-time streaming of fluorescence intensity, lifetime, and phasor imaging data through simultaneous image acquisition and instantaneous data processing. Instant FLIM can be easily implemented by upgrading an existing two-photon microscope using cost-effective components and our open-source software. We further improve the functionality, penetration depth, and resolution of instant FLIM using phasor segmentation, adaptive optics, and super-resolution techniques. We demonstrate through-skull intravital 3D FLIM of mouse brains to depths of 300 m and present the first in vivo 4D FLIM of microglial dynamics in intact and injured zebrafish and mouse brains up to 12 hours.
]]></description>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Guldner, I. H.</dc:creator>
<dc:creator>Nichols, E. L.</dc:creator>
<dc:creator>Benirschke, D.</dc:creator>
<dc:creator>Smith, C. J.</dc:creator>
<dc:creator>Zhang, S.</dc:creator>
<dc:creator>Howard, S. S.</dc:creator>
<dc:date>2020-02-06</dc:date>
<dc:identifier>doi:10.1101/2020.02.05.936039</dc:identifier>
<dc:title><![CDATA[Instant FLIM enables 4D in vivo lifetime imaging of intact brains]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.07.939504v1?rss=1">
<title>
<![CDATA[
A fast genetically encoded fluorescent sensor for faithful in vivo acetylcholine detection in mice, fish, worms and flies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.07.939504v1?rss=1</link>
<description><![CDATA[
Here we design and optimize a genetically encoded fluorescent indicator, iAChSnFR, for the ubiquitous neurotransmitter acetylcholine, based on a bacterial periplasmic binding protein. iAChSnFR shows large fluorescence changes, rapid rise and decay kinetics, and insensitivity to most cholinergic drugs. iAChSnFR revealed large transients in a variety of slice and in vivo preparations in mouse, fish, fly and worm. iAChSnFR will be useful for the study of acetylcholine in all animals.
]]></description>
<dc:creator>Borden, P. M.</dc:creator>
<dc:creator>Zhang, P.</dc:creator>
<dc:creator>Shivange, A. V.</dc:creator>
<dc:creator>Marvin, J. S.</dc:creator>
<dc:creator>Cichon, J.</dc:creator>
<dc:creator>Dan, C.</dc:creator>
<dc:creator>Podgorski, K.</dc:creator>
<dc:creator>Figueiredo, A.</dc:creator>
<dc:creator>Novak, O.</dc:creator>
<dc:creator>Tanimoto, M.</dc:creator>
<dc:creator>Shigetomi, E.</dc:creator>
<dc:creator>Lobas, M. A.</dc:creator>
<dc:creator>Kim, H.</dc:creator>
<dc:creator>Zhu, P. K.</dc:creator>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Zheng, W. S.</dc:creator>
<dc:creator>Fan, C.</dc:creator>
<dc:creator>Wang, G.</dc:creator>
<dc:creator>Xiang, B.</dc:creator>
<dc:creator>Gan, L.</dc:creator>
<dc:creator>Zhang, G.-X.</dc:creator>
<dc:creator>Guo, K.</dc:creator>
<dc:creator>Lin, L.</dc:creator>
<dc:creator>Cai, Y.</dc:creator>
<dc:creator>Yee, A.</dc:creator>
<dc:creator>Aggarwal, A.</dc:creator>
<dc:creator>Ford, C. P.</dc:creator>
<dc:creator>Rees, D. C.</dc:creator>
<dc:creator>Dietrich, D.</dc:creator>
<dc:creator>KHAKH, B. S.</dc:creator>
<dc:creator>Dittman, J. S.</dc:creator>
<dc:creator>Gan, W.-B.</dc:creator>
<dc:creator>Koyama, M. S.</dc:creator>
<dc:creator>Jayaraman, V.</dc:creator>
<dc:creator>Cheer, J. F.</dc:creator>
<dc:creator>Lester, H. A.</dc:creator>
<dc:creator>Zhu, J. J.</dc:creator>
<dc:creator>Looger, L. L.</dc:creator>
<dc:date>2020-02-08</dc:date>
<dc:identifier>doi:10.1101/2020.02.07.939504</dc:identifier>
<dc:title><![CDATA[A fast genetically encoded fluorescent sensor for faithful in vivo acetylcholine detection in mice, fish, worms and flies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.10.940734v1?rss=1">
<title>
<![CDATA[
Ecotype Simulation 2: An improved algorithm for efficiently demarcating microbial species from large sequence datasets 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.10.940734v1?rss=1</link>
<description><![CDATA[
BackgroundMicrobial systematists have used molecular cutoffs to classify the vast diversity present within a natural microbial community without invoking ecological theory. The use of ecological theory is needed to identify whether or not demarcated groups are the ecologically distinct, fundamental units (ecotypes), necessary for understanding the system. Ecotype Simulation, a Monte-Carlo approach to modeling the evolutionary dynamics of a microbial population based on the Stable Ecotype Model of microbial speciation, has proven useful for finding these fundamental units. For instance, predicted ecotypes of Synechococcus forming microbial mats in Yellowstone National Park hot springs, which were previously considered to be a single species based on phenotype, have been shown to be ecologically distinct, with specialization to different temperature and light levels. Unfortunately, development of high-throughput DNA sequencing methods has outpaced the ability of the program to analyze all of the sequence data produced.

ResultsWe developed an improved version of the program called Ecotype Simulation 2, which can rapidly analyze alignments of very large sequence datasets. For instance, while the older version takes days to analyze 200 sequences, the new version can analyze 1.92 x 105 sequences in about six hours. The faster simulation identified similar ecotypes as found with the slower version, but from larger amounts of sequence data.

ConclusionsBased on ecological theory, Ecotype Simulation 2 provides a much-needed approach that will help guide microbial ecologists and systematists to the natural, fundamental units of bacterial diversity.
]]></description>
<dc:creator>Wood, J. M.</dc:creator>
<dc:creator>Becraft, E. M.</dc:creator>
<dc:creator>Cohan, F.</dc:creator>
<dc:creator>Krizanc, D.</dc:creator>
<dc:creator>Ward, D. M.</dc:creator>
<dc:date>2020-02-12</dc:date>
<dc:identifier>doi:10.1101/2020.02.10.940734</dc:identifier>
<dc:title><![CDATA[Ecotype Simulation 2: An improved algorithm for efficiently demarcating microbial species from large sequence datasets]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.15.950840v1?rss=1">
<title>
<![CDATA[
Model Reduction Tools For Phenomenological Modeling of Input-Controlled Biological Circuits 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.15.950840v1?rss=1</link>
<description><![CDATA[
We present a Python-based software package to automatically obtain phenomenological models of input-controlled synthetic biological circuits from descriptive models. From the parts and mechanism description of a synthetic biological circuit, it is easy to obtain a chemical reaction model of the circuit under the assumptions of mass-action kinetics using various existing tools. However, using these models to guide design decisions during an experiment is difficult due to a large number of reaction rate parameters and species in the model. Hence, phenomenological models are often developed that describe the effective relationships among the circuit inputs, outputs, and only the key states and parameters. In this paper, we present an algorithm to obtain these phenomenological models in an automated manner using a Python package for circuits with inputs that control the desired outputs. This model reduction approach combines the common assumptions of time-scale separation, conservation laws, and species abundance to obtain the reduced models that can be used for design of synthetic biological circuits. We consider an example of a simple gene expression circuit and another example of a layered genetic feedback control circuit to demonstrate the use of the model reduction procedure.
]]></description>
<dc:creator>Pandey, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2020-02-15</dc:date>
<dc:identifier>doi:10.1101/2020.02.15.950840</dc:identifier>
<dc:title><![CDATA[Model Reduction Tools For Phenomenological Modeling of Input-Controlled Biological Circuits]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.16.951780v1?rss=1">
<title>
<![CDATA[
The Structures of Secretory and Dimeric Immunoglobulin A 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.16.951780v1?rss=1</link>
<description><![CDATA[
Secretory (S) Immunoglobulin (I) A is the predominant mucosal antibody, which binds pathogens and commensal microbes. SIgA is a polymeric antibody, typically containing two copies of IgA that assemble with one joining-chain (JC) to form dimeric (d) IgA that is bound by the polymeric Ig-receptor ectodomain, called secretory component (SC). Here we report the cryo-electron microscopy structures of murine SIgA and dIgA. Structures reveal two IgAs conjoined through four heavy-chain tailpieces and the JC that together form a {beta}-sandwich-like fold. The two IgAs are bent and tilted with respect to each other, forming distinct concave and convex surfaces. In SIgA, SC is bound to one face, asymmetrically contacting both IgAs and JC. The bent and tilted arrangement of complex components limits the possible positions of both sets of antigen binding fragments (Fabs) and preserves steric accessibility to receptor binding sites, likely influencing antigen binding and effector functions.
]]></description>
<dc:creator>Kumar Bharathkar, S.</dc:creator>
<dc:creator>Parker, B. W.</dc:creator>
<dc:creator>Malyutin, A.</dc:creator>
<dc:creator>Haloi, N.</dc:creator>
<dc:creator>Tajkhorshid, E.</dc:creator>
<dc:creator>Stadtmueller, B.</dc:creator>
<dc:date>2020-02-17</dc:date>
<dc:identifier>doi:10.1101/2020.02.16.951780</dc:identifier>
<dc:title><![CDATA[The Structures of Secretory and Dimeric Immunoglobulin A]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.18.952945v1?rss=1">
<title>
<![CDATA[
Distinct representations of finger movement and force in human motor and premotor cortices 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.18.952945v1?rss=1</link>
<description><![CDATA[
The ability to grasp and manipulate objects requires controlling both finger movement kinematics and isometric force. Previous work suggests that these behavioral modes are controlled separately, but it is unknown whether the cerebral cortex represents them differently. Here, we investigated this question by recording high-density electrocorticography from the motor and premotor cortices of seven human subjects performing a sequential movement-force motor task. We decoded finger movement (0.7{+/-}0.3 fractional variance account for; FVAF) and force (0.7{+/-}0.2 FVAF) with high accuracy, yet found different spatial representations. We also found clear distinctions in electrocorticographic activity by using deep learning methods to uncover state-space representations, and by developing a new metric, the neural vector angle. Thus, state-space techniques can help to investigate broad cortical networks. Finally, we were able to classify the behavioral mode from neural signals with high accuracy (90{+/-}6%). Thus, finger movement and force have distinct representations in motor/premotor cortices. This will inform our understanding of the neural control of movement as well as the design of grasp brain-machine interfaces.
]]></description>
<dc:creator>Flint, R. D.</dc:creator>
<dc:creator>Tate, M. C.</dc:creator>
<dc:creator>Li, K.</dc:creator>
<dc:creator>Templer, J. W.</dc:creator>
<dc:creator>Rosenow, J. M.</dc:creator>
<dc:creator>Pandarinath, C.</dc:creator>
<dc:creator>Slutzky, M. W.</dc:creator>
<dc:date>2020-02-19</dc:date>
<dc:identifier>doi:10.1101/2020.02.18.952945</dc:identifier>
<dc:title><![CDATA[Distinct representations of finger movement and force in human motor and premotor cortices]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.18.953620v1?rss=1">
<title>
<![CDATA[
A geometric and structural approach to the analysis and design of biological circuit dynamics: a theory tailored for synthetic biology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.18.953620v1?rss=1</link>
<description><![CDATA[
Much of the progress in developing our ability to successfully design genetic circuits with predictable dynamics has followed the strategy of molding biological systems to fit into conceptual frameworks used in other disciplines, most notably the engineering sciences. Because biological systems have fundamental differences from systems in these other disciplines, this approach is challenging and the insights obtained from such analyses are often not framed in a biologically-intuitive way. Here, we present a new theoretical framework for analyzing the dynamics of genetic circuits that is tailored towards the unique properties associated with biological systems and experiments. Our framework approximates a complex circuit as a set of simpler circuits, which the system can transition between by saturating its various internal components. These approximations are connected to the intrinsic structure of the system, so this representation allows the analysis of dynamics which emerge solely from the systems structure. Using our framework, we analyze the presence of structural bistability in a leaky autoactivation motif and the presence of structural oscillations in the Repressilator.
]]></description>
<dc:creator>Marken, J. P.</dc:creator>
<dc:creator>Xiao, F.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2020-02-19</dc:date>
<dc:identifier>doi:10.1101/2020.02.18.953620</dc:identifier>
<dc:title><![CDATA[A geometric and structural approach to the analysis and design of biological circuit dynamics: a theory tailored for synthetic biology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.21.958678v1?rss=1">
<title>
<![CDATA[
Imaging cell lineage with a synthetic digital recording system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.21.958678v1?rss=1</link>
<description><![CDATA[
Multicellular development depends on the differentiation of cells into specific fates with precise spatial organization. Lineage history plays a pivotal role in cell fate decisions, but is inaccessible in most contexts. Engineering cells to actively record lineage information in a format readable in situ would provide a spatially resolved view of lineage in diverse developmental processes. Here, we introduce a serine integrase-based recording system that allows in situ readout, and demonstrate its ability to reconstruct lineage relationships in cultured stem cells and flies. The system, termed intMEMOIR, employs an array of independent three-state genetic memory elements that can recombine stochastically and irreversibly, allowing up to 59,049 distinct digital states. intMEMOIR accurately reconstructed lineage trees in stem cells and enabled simultaneous analysis of single cell clonal history, spatial position, and gene expression in Drosophila brain sections. These results establish a foundation for microscopy-readable clonal analysis and recording in diverse systems.

One sentence summaryA new genetic editing system termed intMEMOIR reveals the lineage histories of individual cells directly within their native tissue context.
]]></description>
<dc:creator>Chow, K.-H. K.</dc:creator>
<dc:creator>Budde, M. W.</dc:creator>
<dc:creator>Granados, A. A.</dc:creator>
<dc:creator>Cabrera, M.</dc:creator>
<dc:creator>Yoon, S.</dc:creator>
<dc:creator>Cho, S.</dc:creator>
<dc:creator>Huang, T.-h.</dc:creator>
<dc:creator>Koulena, N.</dc:creator>
<dc:creator>Frieda, K. L.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:creator>Lois, C.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:date>2020-02-25</dc:date>
<dc:identifier>doi:10.1101/2020.02.21.958678</dc:identifier>
<dc:title><![CDATA[Imaging cell lineage with a synthetic digital recording system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.28.968941v1?rss=1">
<title>
<![CDATA[
Metabolic multi-stability and hysteresis in a model aerobe-anaerobe microbiome community 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.28.968941v1?rss=1</link>
<description><![CDATA[
Changes in the composition of the human microbiome are associated with health and disease. Some microbiome states persist in seemingly unfavorable conditions, e.g., the proliferation of aerobe-anaerobe communities in oxygen-exposed environments in wounds or small intestinal bacterial overgrowth. However, it remains unclear how different stable microbiome states can exist under the same conditions, or why some states persist under seemingly unfavorable conditions. Here, using two microbes relevant to the human microbiome, we combine genome-scale mathematical modeling, bioreactor experiments, transcriptomics, and dynamical systems theory, to show that multi-stability and hysteresis (MSH) is a mechanism that can describe the shift from an aerobe-dominated state to a resilient, paradoxically persistent aerobe-anaerobe state. We examine the impact of changing oxygen and nutrient regimes and identify factors, including changes in metabolism and gene expression, that lead to MSH. When analyzing the transitions between the two states in this system, the familiar conceptual connection between causation and correlation is broken and MSH must be used to interpret the dynamics. Using MSH to analyze microbiome dynamics will improve our conceptual understanding of the stability of microbiome states and the transitions among microbiome states.

One sentence summaryMulti-stability and hysteresis (MSH) is a potential mechanism to describe shifts to and persistence of aerobe-anaerobe communities in the microbiome.
]]></description>
<dc:creator>Khazaei, T.</dc:creator>
<dc:creator>Williams, R. L.</dc:creator>
<dc:creator>Bogatyrev, S. R.</dc:creator>
<dc:creator>Doyle, J. C.</dc:creator>
<dc:creator>Henry, C. S.</dc:creator>
<dc:creator>Ismagilov, R. F.</dc:creator>
<dc:date>2020-02-29</dc:date>
<dc:identifier>doi:10.1101/2020.02.28.968941</dc:identifier>
<dc:title><![CDATA[Metabolic multi-stability and hysteresis in a model aerobe-anaerobe microbiome community]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.28.969527v1?rss=1">
<title>
<![CDATA[
Improved reference genome of the arboviral vector Aedes albopictus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.28.969527v1?rss=1</link>
<description><![CDATA[
The Asian tiger mosquito Aedes albopictus is globally expanding and has become the main vector for human arboviruses in Europe. Here we present AalbF2, a dramatically improved assembly of the Ae. albopictus genome that has revealed widespread viral insertions, novel microRNAs and piRNA clusters, the sex determining locus, new immunity genes, and has enabled genome-wide studies of geographically diverse Ae. albopictus populations and analyses of the developmental and stage-dependent network of expression data. Additionally, we built the first physical map for this species with 75% of the assembled genome anchored to the chromosomes. These up-to-date resources of the genome provide a foundation to improve understanding of the adaptation potential and the epidemiological relevance of this species and foster the development of innovative control measures.

One Sentence SummaryLong-read and Hi-C-based de novo assembly of the arboviral vector Aedes albopictus genome fosters deeper understanding of its biological features.
]]></description>
<dc:creator>Palatini, U.</dc:creator>
<dc:creator>Masri, R.</dc:creator>
<dc:creator>Cosme, L. V.</dc:creator>
<dc:creator>Koren, S.</dc:creator>
<dc:creator>Thibaud-Nissen, F.</dc:creator>
<dc:creator>Biedler, J. K.</dc:creator>
<dc:creator>Krsticevic, F.</dc:creator>
<dc:creator>Johnston, S.</dc:creator>
<dc:creator>Halbach, R.</dc:creator>
<dc:creator>Crawford, J. E.</dc:creator>
<dc:creator>Antoshechkin, I.</dc:creator>
<dc:creator>Failloux, A.-B.</dc:creator>
<dc:creator>Pischedda, E.</dc:creator>
<dc:creator>Marconcini, M.</dc:creator>
<dc:creator>Ghurye, J.</dc:creator>
<dc:creator>Rhie, A.</dc:creator>
<dc:creator>Sharma, A.</dc:creator>
<dc:creator>Karagodin, D. A.</dc:creator>
<dc:creator>Jentette, J.</dc:creator>
<dc:creator>Gamez, S.</dc:creator>
<dc:creator>Miesen, P.</dc:creator>
<dc:creator>Caccone, A.</dc:creator>
<dc:creator>Sharakhova, M. V.</dc:creator>
<dc:creator>Tu, Z.</dc:creator>
<dc:creator>Papathanos, P. A.</dc:creator>
<dc:creator>van Rij, R. P.</dc:creator>
<dc:creator>Akbari, O. S.</dc:creator>
<dc:creator>Powell, J.</dc:creator>
<dc:creator>Phillippy, A. M.</dc:creator>
<dc:creator>Bonizzoni, M.</dc:creator>
<dc:date>2020-02-28</dc:date>
<dc:identifier>doi:10.1101/2020.02.28.969527</dc:identifier>
<dc:title><![CDATA[Improved reference genome of the arboviral vector Aedes albopictus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.28.970087v1?rss=1">
<title>
<![CDATA[
A Quantitative Sequencing Framework for Absolute Abundance Measurements of Mucosal and Lumenal Microbial Communities 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.28.970087v1?rss=1</link>
<description><![CDATA[
A fundamental goal in microbiome studies is to determine which microbes affect host physiology. Standard methods for determining changes in microbial taxa measure relative microbial abundances, which cannot capture absolute changes. Moreover, studies often focus on a single site (usually stool), although microbial demographics differ substantially among gastrointestinal (GI) locations. Here, we developed a quantitative framework to accurately measure absolute abundances of individual bacterial taxa by combining the precision of digital PCR with the high-throughput nature of 16S rRNA gene amplicon sequencing. In a murine ketogenic-diet study, we compared microbial loads in lumenal and mucosal samples at several sites along the GI tract. Measurements of absolute (but not relative) abundances revealed decreases in total microbial loads on the ketogenic diet and enabled us to accurately determine the effect of the diet on each taxon at each GI location. Quantitative measurements also revealed different patterns in how the ketogenic diet affected each taxons abundance in stool and small-intestine mucosa samples. This rigorous quantitative microbial analysis framework applied to samples from relevant GI locations will enable mapping microbial biogeography of the mammalian GI tract and more accurately capture the changes of microbial taxa in experimental microbiome studies.
]]></description>
<dc:creator>Barlow, J. T.</dc:creator>
<dc:creator>Bogatyrev, S. R.</dc:creator>
<dc:creator>Ismagilov, R. F.</dc:creator>
<dc:date>2020-02-28</dc:date>
<dc:identifier>doi:10.1101/2020.02.28.970087</dc:identifier>
<dc:title><![CDATA[A Quantitative Sequencing Framework for Absolute Abundance Measurements of Mucosal and Lumenal Microbial Communities]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.29.970558v1?rss=1">
<title>
<![CDATA[
An integrated transcriptomic and epigenomic atlas of mouse primary motor cortex cell types 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.29.970558v1?rss=1</link>
<description><![CDATA[
Single cell transcriptomics has transformed the characterization of brain cell identity by providing quantitative molecular signatures for large, unbiased samples of brain cell populations. With the proliferation of taxonomies based on individual datasets, a major challenge is to integrate and validate results toward defining biologically meaningful cell types. We used a battery of single-cell transcriptome and epigenome measurements generated by the BRAIN Initiative Cell Census Network (BICCN) to comprehensively assess the molecular signatures of cell types in the mouse primary motor cortex (MOp). We further developed computational and statistical methods to integrate these multimodal data and quantitatively validate the reproducibility of the cell types. The reference atlas, based on more than 600,000 high quality single-cell or -nucleus samples assayed by six molecular modalities, is a comprehensive molecular account of the diverse neuronal and non-neuronal cell types in MOp. Collectively, our study indicates that the mouse primary motor cortex contains over 55 neuronal cell types that are highly replicable across analysis methods, sequencing technologies, and modalities. We find many concordant multimodal markers for each cell type, as well as thousands of genes and gene regulatory elements with discrepant transcriptomic and epigenomic signatures. These data highlight the complex molecular regulation of brain cell types and will directly enable design of reagents to target specific MOp cell types for functional analysis.
]]></description>
<dc:creator>Yao, Z.</dc:creator>
<dc:creator>Liu, H.</dc:creator>
<dc:creator>Xie, F.</dc:creator>
<dc:creator>Fischer, S.</dc:creator>
<dc:creator>Adkins, R. S.</dc:creator>
<dc:creator>Aldrige, A. I.</dc:creator>
<dc:creator>Ament, S. A.</dc:creator>
<dc:creator>Bartlett, A.</dc:creator>
<dc:creator>Behrens, M. M.</dc:creator>
<dc:creator>Van den Berge, K.</dc:creator>
<dc:creator>Bertagnolli, D.</dc:creator>
<dc:creator>Biancalani, T.</dc:creator>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Corrada Bravo, H.</dc:creator>
<dc:creator>Casper, T.</dc:creator>
<dc:creator>Colantuoni, C.</dc:creator>
<dc:creator>Crabtree, J.</dc:creator>
<dc:creator>Creasy, H.</dc:creator>
<dc:creator>Crichton, K.</dc:creator>
<dc:creator>Crow, M.</dc:creator>
<dc:creator>Dee, N.</dc:creator>
<dc:creator>Dougherty, E. L.</dc:creator>
<dc:creator>Doyle, W. I.</dc:creator>
<dc:creator>Dudoit, S.</dc:creator>
<dc:creator>Fang, R.</dc:creator>
<dc:creator>Felix, V.</dc:creator>
<dc:creator>Fong, O.</dc:creator>
<dc:creator>Giglio, M.</dc:creator>
<dc:creator>Goldy, J.</dc:creator>
<dc:creator>Hawrylycz, M.</dc:creator>
<dc:creator>Bezieux, H. R. d.</dc:creator>
<dc:creator>Herb, B. R.</dc:creator>
<dc:creator>Hertzano, R.</dc:creator>
<dc:creator>Hou, X.</dc:creator>
<dc:creator>Hu, Q.</dc:creator>
<dc:creator>Huang, Z. J.</dc:creator>
<dc:creator>Kancherla, J.</dc:creator>
<dc:creator>Kroll, M.</dc:creator>
<dc:creator>Lathia, K.</dc:creator>
<dc:creator>Li, Y. E.</dc:creator>
<dc:creator>Lucero, J. D.</dc:creator>
<dc:creator>Luo, C.</dc:creator>
<dc:creator>Mahurkar, A.</dc:creator>
<dc:creator>McMillen, D.</dc:creator>
<dc:creator>Nadaf, N. M.</dc:creator>
<dc:creator>Ner</dc:creator>
<dc:date>2020-03-02</dc:date>
<dc:identifier>doi:10.1101/2020.02.29.970558</dc:identifier>
<dc:title><![CDATA[An integrated transcriptomic and epigenomic atlas of mouse primary motor cortex cell types]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-03-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.03.01.971358v1?rss=1">
<title>
<![CDATA[
pAgo-induced DNA interference protects bacteria from invader DNA 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.03.01.971358v1?rss=1</link>
<description><![CDATA[
Members of the conserved Argonaute protein family use small RNA guides to find their mRNA targets to regulate gene expression and suppress mobile genetic elements in eukaryotes. Argonautes are also present in many bacterial and archaeal species 1-3. Unlike eukaryotic proteins, several studied prokaryotic Argonautes use small DNA guides to cleave DNA, a process dubbed DNA interference 4-8. However, the natural functions and targets of DNA interference are poorly understood and the mechanisms of DNA guide generation and target discrimination remain unknown. Here, we studied the in vivo activities of a bacterial Argonaute nuclease CbAgo and demonstrated that it induces cleavage of multicopy genetic elements, including plasmids, transposons and repetitive chromosomal loci. Generation of small DNA guides employed by CbAgo requires cooperation between its intrinsic endonuclease activity and the cellular double-strand break repair machinery. The mechanism of guide generation ensures that small DNA guides are enriched in sequences that target foreign DNA and endows CbAgo with capacity to eliminate plasmids and fight phage infection. Similar principles may underlie the specificity of self-nonself discrimination by diverse defense systems in prokaryotes.
]]></description>
<dc:creator>Kuzmenko, A.</dc:creator>
<dc:creator>Oguienko, A.</dc:creator>
<dc:creator>Esyunina, D.</dc:creator>
<dc:creator>Yudin, D.</dc:creator>
<dc:creator>Petrova, M.</dc:creator>
<dc:creator>Kudinova, A.</dc:creator>
<dc:creator>Maslova, O.</dc:creator>
<dc:creator>Ninova, M.</dc:creator>
<dc:creator>Ryazansky, S.</dc:creator>
<dc:creator>Leach, D.</dc:creator>
<dc:creator>Aravin, A. A.</dc:creator>
<dc:creator>Kulbachinskiy, A.</dc:creator>
<dc:date>2020-03-03</dc:date>
<dc:identifier>doi:10.1101/2020.03.01.971358</dc:identifier>
<dc:title><![CDATA[pAgo-induced DNA interference protects bacteria from invader DNA]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-03-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.03.02.973560v1?rss=1">
<title>
<![CDATA[
HCN domain is required for HCN channel expression and couples voltage- and cAMP-dependent gating mechanisms 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.03.02.973560v1?rss=1</link>
<description><![CDATA[
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are major regulators of synaptic plasticity, and rhythmic activity in the heart and brain. Opening of HCN channels requires membrane hyperpolarization and is further facilitated by intracellular cyclic nucleotides (cNMPs). In HCN channels, membrane hyperpolarization is sensed by the membrane-spanning voltage sensor domain (VSD) and the cNMP-dependent gating is mediated by the intracellular cyclic nucleotide-binding domain (CNBD) connected to the pore-forming S6 transmembrane domain via the C-linker. Previous functional analysis of HCN channels suggested a direct or allosteric coupling between the voltage- and cNMP-dependent activation mechanisms. However, the specifics of the coupling were unclear. The first cryo-EM structure of an HCN1 channel revealed that a novel structural element, dubbed HCN domain (HCND), forms a direct structural link between the VSD and C-linker/CNBD. In this study, we investigated the functional significance of the HCND. Deletion of the HCND prevented surface expression of HCN2 channels. Based on the HCN1 structure analysis, we identified R237 and G239 residues on the S2 of the VSD that form direct interactions with I135 on the HCND. Disrupting these interactions abolished HCN2 currents. We then identified three residues on the C-linker/CNBD (E478, Q382 and H559) that form direct interactions with residues R154 and S158 on the HCND. Disrupting these interactions affected both voltage- and cAMP-dependent gating of HCN2 channels. These findings indicate that the HCND is necessary for the surface expression of HCN channels, and provides a functional link between the voltage- and cAMP-dependent mechanisms of HCN channel gating.
]]></description>
<dc:creator>Wang, Z.-J.</dc:creator>
<dc:creator>Blanco, I.</dc:creator>
<dc:creator>Hayoz, S.</dc:creator>
<dc:creator>Brelidze, T. I.</dc:creator>
<dc:date>2020-03-02</dc:date>
<dc:identifier>doi:10.1101/2020.03.02.973560</dc:identifier>
<dc:title><![CDATA[HCN domain is required for HCN channel expression and couples voltage- and cAMP-dependent gating mechanisms]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-03-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.03.03.975896v1?rss=1">
<title>
<![CDATA[
CryoEM structure of the Vibrio cholerae Type IV competence pilus secretin PilQ 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.03.03.975896v1?rss=1</link>
<description><![CDATA[
Natural transformation is the process by which bacteria take up genetic material from their environment and integrate it into their genome by homologous recombination. It represents one mode of horizontal gene transfer and contributes to the spread of traits like antibiotic resistance. In Vibrio cholerae, the Type IV competence pilus is thought to facilitate natural transformation by extending from the cell surface, binding to exogenous DNA, and retracting to thread this DNA through the outer membrane secretin, PilQ. A lack of structural information has hindered our understanding of this process, however. Here, we solved the first ever high-resolution structure of a Type IV competence pilus secretin. A functional tagged allele of VcPilQ purified from native V. cholerae cells was used to determine the cryoEM structure of the PilQ secretin in amphipol to [~]2.7 [A]. This structure highlights for the first time key differences in the architecture of the Type IV competence pilus secretin from the Type II and Type III Secretin System secretins. Based on our cryoEM structure, we designed a series of mutants to interrogate the mechanism of PilQ. These experiments provide insight into the channel that DNA likely traverses to promote the spread of antibiotic resistance via horizontal gene transfer by natural transformation. We prove that it is possible to reduce pilus biogenesis and natural transformation by sealing the gate, suggesting VcPilQ as a new drug target.
]]></description>
<dc:creator>Weaver, S. J.</dc:creator>
<dc:creator>Sazinsky, M. H.</dc:creator>
<dc:creator>Dalia, T. N.</dc:creator>
<dc:creator>Dalia, A. B.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2020-03-04</dc:date>
<dc:identifier>doi:10.1101/2020.03.03.975896</dc:identifier>
<dc:title><![CDATA[CryoEM structure of the Vibrio cholerae Type IV competence pilus secretin PilQ]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-03-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.03.05.977991v1?rss=1">
<title>
<![CDATA[
Isoform specificity in the mouse primary motor cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.03.05.977991v1?rss=1</link>
<description><![CDATA[
Full-length SMART-Seq single-cell RNA-seq can be used to measure gene expression at isoform resolution, making possible the identification of isoform markers for cell types and for an isoform atlas. In a comprehensive analysis of 6,160 mouse primary motor cortex cells assayed with SMART-Seq, we find numerous examples of isoform specificity in cell types, including isoform shifts between cell types that are masked in gene-level analysis. These findings can be used to refine spatial gene expression information to isoform resolution. Our results highlight the utility of full-length single-cell RNA-seq when used in conjunction with other single-cell RNA-seq technologies.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Yao, Z.</dc:creator>
<dc:creator>Velthoven, C. v.</dc:creator>
<dc:creator>Smith, K.</dc:creator>
<dc:creator>Tasic, B.</dc:creator>
<dc:creator>Zeng, H.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2020-03-05</dc:date>
<dc:identifier>doi:10.1101/2020.03.05.977991</dc:identifier>
<dc:title><![CDATA[Isoform specificity in the mouse primary motor cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-03-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.03.09.979369v1?rss=1">
<title>
<![CDATA[
An Xist-dependent protein assembly mediates Xist localization and gene silencing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.03.09.979369v1?rss=1</link>
<description><![CDATA[
Nuclear compartments play diverse roles in regulating gene expression, yet the molecular forces and components driving compartment formation are not well understood. Studying how the lncRNA Xist establishes the inactive-X-chromosome (Xi)-compartment, we found that the Xist RNA-binding-proteins PTBP1, MATR3, TDP43, and CELF1 form a condensate to create an Xi-domain that can be sustained in the absence of Xist. The E-repeat-sequence of Xist serves a multivalent binding-platform for these proteins. Without the E-repeat, Xist initially coats the X-chromosome during XCI onset but subsequently disperses across the nucleus with loss of gene silencing. Recruitment of PTBP1, MATR3, TDP-43 or CELF1 to {Delta}E-Xist rescues these phenotypes, and requires both self-association of MATR3 and TDP-43 and a heterotypic PTBP1-MATR3-interaction. Together, our data reveal that Xist sequesters itself within the Xi-territory and perpetuates gene silencing by seeding a protein-condensate. Our findings uncover an unanticipated mechanism for epigenetic memory and elucidate the interplay between RNA and RNA-binding-proteins in creating compartments for gene regulation.
]]></description>
<dc:creator>Plath, K.</dc:creator>
<dc:creator>Black, D. L.</dc:creator>
<dc:creator>Pandya-Jones, A.</dc:creator>
<dc:creator>Markaki, Y.</dc:creator>
<dc:creator>Serizay, J.</dc:creator>
<dc:creator>Chitiashvili, T.</dc:creator>
<dc:creator>Mancia, W.</dc:creator>
<dc:creator>Damianov, A.</dc:creator>
<dc:creator>Chronis, K.</dc:creator>
<dc:creator>Papp, B.</dc:creator>
<dc:creator>Chen, C.-K.</dc:creator>
<dc:creator>McKee, R.</dc:creator>
<dc:creator>Wang, X.-J.</dc:creator>
<dc:creator>Chau, A.</dc:creator>
<dc:creator>Leonhardt, H.</dc:creator>
<dc:creator>Zheng, S.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:date>2020-03-09</dc:date>
<dc:identifier>doi:10.1101/2020.03.09.979369</dc:identifier>
<dc:title><![CDATA[An Xist-dependent protein assembly mediates Xist localization and gene silencing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-03-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.03.09.984013v1?rss=1">
<title>
<![CDATA[
Combined membrane potential imaging and connectome of behavioral circuits in an annelid worm 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.03.09.984013v1?rss=1</link>
<description><![CDATA[
Dorsal Excitor motor neuron DE-3 in the medicinal leech plays three very different dynamical roles in three different behaviors. Without rewiring its anatomical connectivity, how can a motor neuron dynamically switch roles to play appropriate roles in various behaviors? We previously used voltage-sensitive dye imaging to record from DE-3 and most other neurons in the leech segmental ganglion during (fictive) swimming, crawling, and local-bend escape (Tomina and Wagenaar, 2017). Here, we repeated that experiment, then re-imaged the same ganglion using serial blockface electron microscopy and traced all of DE-3s processes. Further, we traced back the processes of all of DE-3s presynaptic partners to their respective somata. This allowed us to analyze the relationship between circuit anatomy and the activity patterns it sustains. We found that input synapses important for all of the behaviors were widely distributed over DE-3s branches, yet that functional clusters were different during (fictive) swimming vs. crawling.
]]></description>
<dc:creator>Ashaber, M.</dc:creator>
<dc:creator>Tomina, Y.</dc:creator>
<dc:creator>Kassraian-Fard, P.</dc:creator>
<dc:creator>Bushong, E. A.</dc:creator>
<dc:creator>Kristan, W. B.</dc:creator>
<dc:creator>Ellisman, M. H.</dc:creator>
<dc:creator>Wagenaar, D. A.</dc:creator>
<dc:date>2020-03-10</dc:date>
<dc:identifier>doi:10.1101/2020.03.09.984013</dc:identifier>
<dc:title><![CDATA[Combined membrane potential imaging and connectome of behavioral circuits in an annelid worm]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-03-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.03.24.006528v1?rss=1">
<title>
<![CDATA[
Layered Feedback Control Improves Robust Functionality across Heterogeneous Cell Populations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.03.24.006528v1?rss=1</link>
<description><![CDATA[
Realizing homeostatic control of metabolites or proteins is one of the key goals of synthetic circuits. However, if control is only implemented internally in individual cells, cell-cell heterogeneity may break the homeostasis on population level since cells do not contribute equally to the production or regulation. New control structures are needed to achieve robust functionality in heterogeneous cell populations. Quorum sensing (QS) serves as a collective mechanism by releasing and sensing small and diffusible signaling molecules for group decision-making. We propose a layered feedback control structure that includes a global controller using quorum sensing and a local controller via internal signal-receptor systems. We demonstrate with modeling and simulation that the global controller drives contributing cells to compensate for disturbances while the local controller governs the fail-mode performance in non-contributing cells. The layered controller can tolerate a higher portion of non-contributing cells or longer generations of mutant cells while maintaining metabolites or proteins level within a small error range, compared with only internal feedback control. We further discuss the potential of such layered structures in robust control of cell population size, population fraction and other population-dependent functions.
]]></description>
<dc:creator>Ren, X.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2020-03-25</dc:date>
<dc:identifier>doi:10.1101/2020.03.24.006528</dc:identifier>
<dc:title><![CDATA[Layered Feedback Control Improves Robust Functionality across Heterogeneous Cell Populations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-03-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.02.021436v1?rss=1">
<title>
<![CDATA[
Transient Pupil Constriction Reflects and Affects Facial Attractiveness 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.02.021436v1?rss=1</link>
<description><![CDATA[
Contrary to the long-held belief of a close linkage between pupil dilation and attractiveness, we found an early and transient pupil constriction response when participants viewed an attractive face (and the effect of luminance/contrast is controlled). While human participants were making an attractiveness judgment on faces, their pupil constricted more for the more attractive (as-to-be-rated) faces. Further experiments showed that the effect of pupil constriction to attractiveness judgment extended to intrinsically aesthetic visual objects such as natural scene images (as well as faces) but not to line-drawing geometric figures. When participants were asked to judge the roundness of faces, pupil constriction still correlated with their attractiveness but not the roundness rating score, indicating the automaticity of the pupil constriction to attractiveness. When pupillary responses were manipulated implicitly by relative background luminance changes (from the pre-stimulus screen), the facial attractiveness ratings were in accordance with the amount of pupil constriction, which could not be explained solely by simultaneous or sequential luminance contrast. The overall results suggest that pupil constriction not only reflects but, as a part of self-monitoring and attribution mechanisms, also possibly contributes facial attractiveness implicitly.
]]></description>
<dc:creator>Liao, H.-I.</dc:creator>
<dc:creator>Kashino, M.</dc:creator>
<dc:creator>Shimojo, S.</dc:creator>
<dc:date>2020-04-03</dc:date>
<dc:identifier>doi:10.1101/2020.04.02.021436</dc:identifier>
<dc:title><![CDATA[Transient Pupil Constriction Reflects and Affects Facial Attractiveness]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.02.021451v1?rss=1">
<title>
<![CDATA[
Decrease in ACE2 mRNA expression in aged mouse lung 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.02.021451v1?rss=1</link>
<description><![CDATA[
Angiotensin-converting enzyme 2 (ACE2) has been identified as a critical receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This has led to extensive speculation on the role of ACE2 in disease severity, and in particular, whether variation in its expression can explain higher mortality in older individuals. We examine this question in mouse lung and show that 24-month old mice have significantly reduced ACE2 mRNA expression relative to 3-month old mice. The differences appear to be localized to ciliated cells.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2020-04-05</dc:date>
<dc:identifier>doi:10.1101/2020.04.02.021451</dc:identifier>
<dc:title><![CDATA[Decrease in ACE2 mRNA expression in aged mouse lung]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.03.024042v1?rss=1">
<title>
<![CDATA[
Common Fronto-temporal Effective Connectivity in Humans and Monkeys 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.03.024042v1?rss=1</link>
<description><![CDATA[
Cognitive pathways supporting human language and declarative memory are thought to have uniquely evolutionarily differentiated in our species. However, cross-species comparisons are missing on site-specific effective connectivity between regions important for cognition. We harnessed a new approach using functional imaging to visualize the impact of direct electrical brain stimulation in human neurosurgery patients. Applying the same approach with macaque monkeys, we found remarkably comparable patterns of effective connectivity between auditory cortex and ventro-lateral prefrontal cortex (vlPFC) and parahippocampal cortex in both species. Moreover, in humans electrical tractography revealed rapid evoked potentials in vlPFC from stimulating auditory cortex and speech sounds drove vlPFC, consistent with prior evidence in monkeys of direct projections from auditory cortex to vocalization responsive regions in vlPFC. The results identify a common effective connectivity signature that from auditory cortex is equally direct to vlPFC and indirect to the hippocampus (via parahippocampal cortex) in human and nonhuman primates.

HighlightsO_LIPrivileged human auditory to inferior frontal connectivity, linked to monkeys
C_LIO_LICommon auditory to parahippocampal effective connectivity in both species
C_LIO_LIGreater lateralization in human effective connectivity, more symmetrical in monkeys
C_LIO_LIHuman fronto-temporal network function rooted in evolutionarily conserved signature
C_LI

eTOC short summaryFunctional connectivity between regions crucial for language and declarative memory is thought to have substantially differentiated in humans. Using a new technique to similarly visualize directional effective connectivity in humans and monkeys, we found remarkably comparable connectivity patterns in both species between fronto-temporal regions crucial for cognition.
]]></description>
<dc:creator>Rocchi, F.</dc:creator>
<dc:creator>Oya, H.</dc:creator>
<dc:creator>Balezeau, F.</dc:creator>
<dc:creator>Billig, A. J.</dc:creator>
<dc:creator>Kocsis, Z.</dc:creator>
<dc:creator>Jenison, R.</dc:creator>
<dc:creator>Nourski, K. V.</dc:creator>
<dc:creator>Kovach, C. K.</dc:creator>
<dc:creator>Steinschneider, M.</dc:creator>
<dc:creator>Kikuchi, Y.</dc:creator>
<dc:creator>Rhone, A. E.</dc:creator>
<dc:creator>Dlouhy, B. J.</dc:creator>
<dc:creator>Kawasaki, H.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:creator>Greenlee, J. D. W.</dc:creator>
<dc:creator>Griffiths, T. D.</dc:creator>
<dc:creator>Howard, M. A.</dc:creator>
<dc:creator>Petkov, C. I.</dc:creator>
<dc:date>2020-04-05</dc:date>
<dc:identifier>doi:10.1101/2020.04.03.024042</dc:identifier>
<dc:title><![CDATA[Common Fronto-temporal Effective Connectivity in Humans and Monkeys]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.06.027227v1?rss=1">
<title>
<![CDATA[
Causally Linking Neural Dominance to Perceptual Dominance in a Multisensory Conflict 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.06.027227v1?rss=1</link>
<description><![CDATA[
When different senses are in conflict, one sense may dominate the perception of other sense, but it is not known whether the sensory cortex associated with the dominant modality exerts directional influence, at the functional brain level, over the sensory cortex associated with the dominated modality; in short, the link between sensory dominance and neuronal dominance is not established. In a task involving audio-visual conflict, using magnetoencephalography recordings in humans, we first demonstrated that the neuronal dominance - visual cortex being functionally influenced by the auditory cortex - was associated with the sensory dominance - participants visual perception being qualitatively altered by sound. Further, we found that prestimulus auditory-to-visual connectivity could predict the perceptual outcome on a trial-by-trial basis. Subsequently, we performed an effective connectivity-guided neurofeedback electroencephalography experiment and showed that participants who were briefly trained to increase the neuronal dominance from auditory to visual cortex also showed higher sensory, i.e. auditory, dominance during the conflict task immediately after the training. The results shed new light into the interactive neuronal nature of multisensory integration and open up exciting opportunities by enhancing or suppressing targeted mental functions subserved by effective connectivity.
]]></description>
<dc:creator>Yun, K.</dc:creator>
<dc:creator>Bhattacharya, J.</dc:creator>
<dc:creator>Sandkuhler, S.</dc:creator>
<dc:creator>Lin, Y.-J.</dc:creator>
<dc:creator>Iwaki, S.</dc:creator>
<dc:creator>Shimojo, S.</dc:creator>
<dc:date>2020-04-06</dc:date>
<dc:identifier>doi:10.1101/2020.04.06.027227</dc:identifier>
<dc:title><![CDATA[Causally Linking Neural Dominance to Perceptual Dominance in a Multisensory Conflict]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.10.036657v1?rss=1">
<title>
<![CDATA[
Large hydrogen isotope fractionations distinguish nitrogenase-derived methane from other sources 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.10.036657v1?rss=1</link>
<description><![CDATA[
Nitrogenase is the main source of natural fixed nitrogen for the biosphere. Two forms of this metalloenzyme, the vanadium (V) and iron (Fe)-only nitrogenases, were recently found to reduce small amounts of carbon dioxide into the potent greenhouse gas methane. Here we report carbon and hydrogen stable isotopic compositions and fractionations of methane generated by V- and Fe-only nitrogenases in the metabolically versatile nitrogen fixer Rhodopseudomonas palustris. The stable carbon isotope fractionation imparted by both forms of alternative nitrogenase are within the range observed for hydrogenotrophic methanogenesis (13CO2/CH4 = 1.051 {+/-} 0.002 for V-nitrogenase and 1.055 {+/-} 0.001 for Fe-only nitrogenase, mean {+/-} SE). In contrast, the hydrogen isotope fractionations (2H2O/CH4 = 2.071 {+/-} 0.014 for V-nitrogenase and 2.078 {+/-} 0.018 for Fe-only nitrogenase) are the largest of any known biogenic or geogenic pathway. The large 2H2O/CH4 shows that the reaction pathway nitrogenases use to form methane strongly discriminates against 2H, and that 2H2O/CH4 distinguishes nitrogenase-derived methane from all other known biotic and abiotic sources. These findings on nitrogenase-derived methane will help constrain carbon and nitrogen flows in microbial communities and the role of the alternative nitrogenases in global biogeochemical cycles.

ImportanceAll forms of life require nitrogen for growth. Many different kinds of microbes living in diverse environments make inert nitrogen gas from the atmosphere bioavailable using a special protein, nitrogenase. Nitrogenase has a wide substrate range, and in addition to producing bioavailable nitrogen, some forms of nitrogenase also produce small amounts of the greenhouse gas methane. This is different from other microbes that produce methane to generate energy. Until now, there was no good way to determine when microbes with nitrogenases are making methane in nature. Here, we developed an isotopic fingerprint that allows scientists to distinguish methane from microbes making it for energy versus those making it as a byproduct of nitrogen acquisition. With this new fingerprint, it will be possible to improve our understanding of the relationship between methane production and nitrogen acquisition in nature.
]]></description>
<dc:creator>Luxem, K. E.</dc:creator>
<dc:creator>Leavitt, W. D.</dc:creator>
<dc:creator>Zhang, X.</dc:creator>
<dc:date>2020-04-12</dc:date>
<dc:identifier>doi:10.1101/2020.04.10.036657</dc:identifier>
<dc:title><![CDATA[Large hydrogen isotope fractionations distinguish nitrogenase-derived methane from other sources]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.12.038331v1?rss=1">
<title>
<![CDATA[
Experimentally-validated correlation analysis reveals new anaerobic methane oxidation partnerships with consortium-level heterogeneity in diazotrophy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.12.038331v1?rss=1</link>
<description><![CDATA[
Archaeal anaerobic methanotrophs ( ANME) and sulfate-reducing Deltaproteobacteria ( SRB) form symbiotic multicellular consortia capable of anaerobic methane oxidation (AOM), and in so doing modulate methane flux from marine sediments. The specificity with which ANME associate with particular SRB partners in situ, however, is poorly understood. To characterize partnership specificity in ANME-SRB consortia, we applied the correlation inference technique SparCC to 310 16S rRNA Illumina iTag amplicon libraries prepared from Costa Rica sediment samples, uncovering a strong positive correlation between ANME-2b and members of a clade of Deltaproteobacteria we termed SEEP-SRB1g. We confirmed this association by examining 16S rRNA diversity in individual ANME-SRB consortia sorted using flow cytometry and by imaging ANME-SRB consortia with fluorescence in situ hybridization (FISH) microscopy using newly-designed probes targeting the SEEP-SRB1g clade. Analysis of genome bins belonging to SEEP-SRB1g revealed the presence of a complete nifHDK operon required for diazotrophy, unusual in published genomes of ANME-associated SRB. Active expression of nifH in SEEP-SRB1g and diazotrophic activity within ANME-2b/SEEP-SRB1g consortia was then demonstrated by microscopy using hybridization chain-reaction (HCR-) FISH targeting nifH transcripts and by FISH-nanoSIMS experiments. NanoSIMS analysis of ANME-2b/SEEP-SRB1g consortia incubated with a headspace containing CH4 and 15N2 revealed differences in cellular 15N-enrichment between the two partners that varied between individual consortia, with SEEP-SRB1g cells enriched in 15N relative to ANME-2b in one consortium and the opposite pattern observed in others, indicating both ANME-2b and SEEP-SRB1g are capable of nitrogen fixation, but with consortium-specific variation in whether the archaea or bacterial partner is the dominant diazotroph.
]]></description>
<dc:creator>Metcalfe, K. S.</dc:creator>
<dc:creator>Murali, R. S.</dc:creator>
<dc:creator>Mullin, S. W.</dc:creator>
<dc:creator>Connon, S. A.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2020-04-13</dc:date>
<dc:identifier>doi:10.1101/2020.04.12.038331</dc:identifier>
<dc:title><![CDATA[Experimentally-validated correlation analysis reveals new anaerobic methane oxidation partnerships with consortium-level heterogeneity in diazotrophy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.16.045146v1?rss=1">
<title>
<![CDATA[
Thermal Control of T-cell Immunotherapy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.16.045146v1?rss=1</link>
<description><![CDATA[
Genetically engineered T-cells are being developed to perform a variety of therapeutic functions. However, no robust mechanisms exist to externally control the activity of T-cells at specific locations within the body. Such spatiotemporal control could help mitigate potential off-target toxicity due to incomplete molecular specificity in applications such as T-cell immunotherapy against solid tumors. Temperature is a versatile external control signal that can be delivered to target tissues in vivo using techniques such as focused ultrasound and magnetic hyperthermia. Here, we test the ability of heat shock promoters to mediate thermal actuation of genetic circuits in primary human T-cells in the well-tolerated temperature range of 37-42{degrees}C, and introduce genetic architectures enabling the tuning of the amplitude and duration of thermal activation. We demonstrate the use of these circuits to control the expression of chimeric antigen receptors and cytokines, and the killing of target tumor cells. This technology provides a critical tool to direct the activity of T-cells after they are deployed inside the body.
]]></description>
<dc:creator>Abedi, M. H.</dc:creator>
<dc:creator>Lee, J.</dc:creator>
<dc:creator>Piraner, D. I.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2020-04-18</dc:date>
<dc:identifier>doi:10.1101/2020.04.16.045146</dc:identifier>
<dc:title><![CDATA[Thermal Control of T-cell Immunotherapy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.16.045237v1?rss=1">
<title>
<![CDATA[
Transcranial Focused Ultrasound Generates Skull-Conducted Shear Waves: Computational Model and Implications for Neuromodulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.16.045237v1?rss=1</link>
<description><![CDATA[
Focused ultrasound (FUS) is an established technique for non-invasive surgery and has recently attracted considerable attention as a potential method for non-invasive neuromodulation. While the pressure waves generated by FUS in this context have been extensively studied, the accompanying shear waves are often neglected due to the relatively high shear compliance of soft tissues. However, in bony structures such as the skull, acoustic pressure can also induce significant shear waves that could propagate outside the ultrasound focus. Here, we investigate wave propagation in the human cranium by means of a finite-element model that accounts for the anatomy, elasticity and viscoelasticity of the skull and brain. We show that, when a region on the frontal lobe is subjected to FUS, the skull acts as a wave guide for shear waves, resulting in their propagation to off-target structures such as the cochlea. This effect helps explain the off-target auditory responses observed during neuromodulation experiments and informs the development of mitigation and sham control strategies.
]]></description>
<dc:creator>Salahshoor, H.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Ortiz, M.</dc:creator>
<dc:date>2020-04-18</dc:date>
<dc:identifier>doi:10.1101/2020.04.16.045237</dc:identifier>
<dc:title><![CDATA[Transcranial Focused Ultrasound Generates Skull-Conducted Shear Waves: Computational Model and Implications for Neuromodulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.16.045534v1?rss=1">
<title>
<![CDATA[
Structure of the bacterial cellulose ribbon and its assembly-guiding cytoskeleton by electron cryotomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.16.045534v1?rss=1</link>
<description><![CDATA[
Cellulose is a widespread component of bacterial biofilms, where its properties of exceptional water retention, high tensile strength and stiffness prevents dehydration and mechanical disruption of the biofilm. Bacteria in the Gluconacetobacter genus secrete crystalline cellulose, with a structure very similar to that found in plant cell walls. How this higher-order structure is produced is poorly understood. We used cryo-electron tomography and focused ion beam milling of native bacterial biofilms to image cellulose-synthesizing G. hansenii and G. xylinus bacteria in a frozen-hydrated, near-native state. We confirm previous results suggesting that cellulose crystallization occurs serially following its secretion along one side of the cell, leading to a cellulose ribbon that can reach several microns in length and combine with ribbons from other cells to form a robust biofilm matrix. We were able to take direct measurements in a near-native state of the cellulose sheets. Our results also reveal a novel cytoskeletal structure, that we name the cortical belt, adjacent to the inner membrane and underlying the sites where cellulose is seen emerging from the cell. We find that this structure is not present in other cellulose-synthesizing bacterial species, Agrobacterium tumefaciens and Escherichia coli 1094, which do not produce organized cellulose ribbons. We therefore propose that the cortical belt holds the cellulose synthase complexes in a line, to form higher-order cellulose structures such as sheets and ribbons.
]]></description>
<dc:creator>NICOLAS, W. J.</dc:creator>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Tocheva, E. I.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2020-04-17</dc:date>
<dc:identifier>doi:10.1101/2020.04.16.045534</dc:identifier>
<dc:title><![CDATA[Structure of the bacterial cellulose ribbon and its assembly-guiding cytoskeleton by electron cryotomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.20.039529v1?rss=1">
<title>
<![CDATA[
A shared neural substrate for action verbs and observed actions in human posterior parietal cortex. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.20.039529v1?rss=1</link>
<description><![CDATA[
High-level sensory and motor cortical areas are activated when processing the meaning of language, but it is unknown whether, and how, words share a neural substrate with corresponding sensorimotor representations. We recorded from single neurons in human posterior parietal cortex (PPC) while participants viewed action verbs and corresponding action videos from multiple views. We find that PPC neurons exhibit a common neural substrate for action verbs and observed actions. Further, videos were encoded with mixtures of invariant and idiosyncratic responses across views. Action verbs elicited selective responses from a fraction of these invariant and idiosyncratic neurons, without preference, thus associating with a statistical sampling of the diverse sensory representations related to the corresponding action concept. Controls indicated the results are not the product of visual imagery nor arbitrary learned associations. Our results suggest that language may activate the consolidated visual experience of the reader.
]]></description>
<dc:creator>Aflalo, T.</dc:creator>
<dc:creator>Zhang, C.</dc:creator>
<dc:creator>Rosario, E.</dc:creator>
<dc:creator>Pouratian, N.</dc:creator>
<dc:creator>Orban, G. A.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2020-04-20</dc:date>
<dc:identifier>doi:10.1101/2020.04.20.039529</dc:identifier>
<dc:title><![CDATA[A shared neural substrate for action verbs and observed actions in human posterior parietal cortex.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.20.041269v1?rss=1">
<title>
<![CDATA[
Neural correlates of cognitive motor signals in primary somatosensory cortex. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.20.041269v1?rss=1</link>
<description><![CDATA[
Classical systems neuroscience positions primary sensory areas as early feed-forward processing stations for refining incoming sensory information. This view may oversimplify their role given extensive bi-directional connectivity with multimodal cortical and subcortical regions. Here we show that single units in human primary somatosensory cortex encode imagined reaches centered on imagined limb positions in a cognitive motor task. This result suggests a broader role of primary somatosensory cortex in cortical function than previously demonstrated.
]]></description>
<dc:creator>Jaffari, M.</dc:creator>
<dc:creator>Aflalo, T.</dc:creator>
<dc:creator>Chivukula, S.</dc:creator>
<dc:creator>Kellis, S.</dc:creator>
<dc:creator>Armenta Salas, M.</dc:creator>
<dc:creator>Norman, S.</dc:creator>
<dc:creator>Pejsa, K.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2020-04-21</dc:date>
<dc:identifier>doi:10.1101/2020.04.20.041269</dc:identifier>
<dc:title><![CDATA[Neural correlates of cognitive motor signals in primary somatosensory cortex.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.20.049437v1?rss=1">
<title>
<![CDATA[
Bacterial defenses against a natural antibiotic promote collateral resilience to clinical antibiotics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.20.049437v1?rss=1</link>
<description><![CDATA[
As antibiotic-resistant infections become increasingly prevalent worldwide, understanding the factors that lead to antimicrobial treatment failure is essential to optimizing the use of existing drugs. Opportunistic human pathogens in particular typically exhibit high levels of intrinsic antibiotic resistance and tolerance1, leading to chronic infections that can be nearly impossible to eradicate2. We asked whether the recalcitrance of these organisms to antibiotic treatment could be driven in part by their evolutionary history as environmental microbes, which frequently produce or encounter natural antibiotics3,4. Using the opportunistic pathogen Pseudomonas aeruginosa as a model, we demonstrate that the self-produced natural antibiotic pyocyanin (PYO) activates bacterial defenses that confer collateral tolerance to certain synthetic antibiotics, including in a clinically-relevant growth medium. Non-PYO-producing opportunistic pathogens isolated from lung infections similarly display increased antibiotic tolerance when they are co-cultured with PYO-producing P. aeruginosa. Furthermore, we show that beyond promoting bacterial survival in the presence of antibiotics, PYO can increase the apparent rate of mutation to antibiotic resistance by up to two orders of magnitude. Our work thus suggests that bacterial production of natural antibiotics in infections could play an important role in modulating not only the immediate efficacy of clinical antibiotics, but also the rate at which antibiotic resistance arises in multispecies bacterial communities.
]]></description>
<dc:creator>Meirelles, L. A.</dc:creator>
<dc:creator>Perry, E. K.</dc:creator>
<dc:creator>Bergkessel, M.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2020-04-20</dc:date>
<dc:identifier>doi:10.1101/2020.04.20.049437</dc:identifier>
<dc:title><![CDATA[Bacterial defenses against a natural antibiotic promote collateral resilience to clinical antibiotics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.21.045195v1?rss=1">
<title>
<![CDATA[
Term Matrix: A novel Gene Ontology annotation quality control system based on ontology term co-annotation patterns 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.21.045195v1?rss=1</link>
<description><![CDATA[
Biological processes are accomplished by the coordinated action of gene products. Gene products often participate in multiple processes, and can therefore be annotated to multiple Gene Ontology (GO) terms. Nevertheless, processes that are functionally, temporally, and/or spatially distant may have few gene products in common, and co-annotation to unrelated processes likely reflects errors in literature curation, ontology structure, or automated annotation pipelines. We have developed an annotation quality control workflow that uses rules based on mutually exclusive processes to detect annotation errors, based on and validated by case studies including the three we present here: fission yeast protein-coding gene annotations over time; annotations for cohesin complex subunits in human and model species; and annotations using a selected set of GO biological process terms in human and five model species. For each case study, we reviewed available GO annotations, identified pairs of biological processes which are unlikely to be correctly co-annotated to the same gene products (e.g., amino acid metabolism and cytokinesis), and traced erroneous annotations to their sources. To date we have generated 107 quality control rules, and corrected 289 manual annotations in eukaryotes and over 2.5 million automatically propagated annotations across all taxa.
]]></description>
<dc:creator>Wood, V.</dc:creator>
<dc:creator>Carbon, S.</dc:creator>
<dc:creator>Harris, M. A.</dc:creator>
<dc:creator>Lock, A.</dc:creator>
<dc:creator>Engel, S. R.</dc:creator>
<dc:creator>Hill, D. P.</dc:creator>
<dc:creator>Van Auken, K.</dc:creator>
<dc:creator>Attrill, H.</dc:creator>
<dc:creator>Feuermann, M.</dc:creator>
<dc:creator>Gaudet, P.</dc:creator>
<dc:creator>Lovering, R. C.</dc:creator>
<dc:creator>Poux, S.</dc:creator>
<dc:creator>Rutherford, K. M.</dc:creator>
<dc:creator>Mungall, C. J.</dc:creator>
<dc:date>2020-04-23</dc:date>
<dc:identifier>doi:10.1101/2020.04.21.045195</dc:identifier>
<dc:title><![CDATA[Term Matrix: A novel Gene Ontology annotation quality control system based on ontology term co-annotation patterns]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.21.050690v1?rss=1">
<title>
<![CDATA[
Sensory-evoked extracellular vesicle release and targeting 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.21.050690v1?rss=1</link>
<description><![CDATA[
Extracellular vesicles (EVs) are emerging as a universal means of cell-to-cell communication and hold great potential in diagnostics and regenerative therapies [1]. An urgent need in the field is a fundamental understanding of physiological mechanisms driving EV generation and function. Ciliary EVs act as signaling devices in Chlamydomonas and C. elegans [2-4]. Mammalian cilia shed EVs to eliminate unwanted receptors [5] or to retract cilia before entering the cell cycle [6]. Here we used our established C. elegans model to study sensory-evoked ciliary EV release and targeting using a fluorescently labeled EV cargo polycystin-2 (PKD-2). In C. elegans and mammals, the Autosomal Dominant Polycystic Kidney Disease (ADPKD) gene products polycystin-1 and polycystin-2 localize to cilia and EVs, act in the same genetic pathway, and function in a sensory capacity, suggesting ancient conservation [7]. We find that males deposit PKD-2-carrying EVs onto the vulva of the hermaphrodite during mating. We also show that mechanical stimulation triggers release of PKD-2-carrying EVs from cilia. To our knowledge this is the first report of mechanoresponsive nature of the ciliary EV release and of ciliary EV directional transfer from one animal to another animal. Since the polycystins are evolutionarily conserved ciliary EV cargoes, our findings suggest that similar mechanisms for EV release and targeting may occur in other systems and biological contexts.
]]></description>
<dc:creator>Wang, J.</dc:creator>
<dc:creator>Nikonorova, I. A.</dc:creator>
<dc:creator>Gu, A.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Barr, M. M.</dc:creator>
<dc:date>2020-04-22</dc:date>
<dc:identifier>doi:10.1101/2020.04.21.050690</dc:identifier>
<dc:title><![CDATA[Sensory-evoked extracellular vesicle release and targeting]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.21.052647v1?rss=1">
<title>
<![CDATA[
Modulation of the tumour promoting functions of cancer associated fibroblasts by phosphodiesterase type 5 inhibition increases the efficacy of chemotherapy in human preclinical models of esophageal adenocarcinoma. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.21.052647v1?rss=1</link>
<description><![CDATA[
Background and aimsEsophageal adenocarcinoma (EAC) is chemoresistant in the majority of cases. The tumor-promoting biology of cancer associated fibroblasts (CAF) make them a target for novel therapies. Phosphodiesterase type 5 inhibitors (PDE5i) have been shown to regulate the activated fibroblast phenotype in benign disease. We investigated the potential for CAF modulation in EAC using PDE5i to enhance the efficacy of chemotherapy.

MethodsEAC fibroblasts were treated with PDE5i and phenotypic effects examined using immunoblotting, immunohistochemistry, gel contraction, transwell invasion, organotypics, single cell RNAseq and shotgun proteomics. The combination of PDE5i with standard-of-care chemotherapy (Epirubicin, 5-Fluorouracil and Cisplatin) was tested for safety and efficacy in validated near-patient model systems (3D tumor growth assays (3D-TGAs) and patient derived xenograft (PDX) mouse models).

ResultsPDE5i treatment reduced -SMA expression in CAFs by 50% (p<0.05), associated with a significant reduction in the ability of CAFs to contract collagen-1 gels and induce cancer cell invasion, (p<0.05). RNAseq and proteomic analysis of CAF and EAC cell lines revealed PDE5i specific regulation of pathways related to fibroblast activation and tumor promotion. 3D-TGA assays confirmed the importance of stromal cells to chemoresistance in EAC, which could be attenuated by PDE5i. Chemotherapy+PDE5i in PDX-bearing mice was safe and significantly reduced PDX tumor volume (p<0.05).

ConclusionPDE5 is a candidate for clinical trials to alter the fibroblast phenotype in esophageal cancer. We demonstrate the specificity of PDE5i for fibroblasts to prevent transdifferentiation and revert the CAF phenotype. Finally, we confirm the efficacy of PDE5i in combination with chemotherapy in close-to-patient in vitro and in vivo PDX-based model systems.
]]></description>
<dc:creator>Hayden, A.</dc:creator>
<dc:creator>Manousopoulou, A.</dc:creator>
<dc:creator>Cowie, A.</dc:creator>
<dc:creator>Walker, R.</dc:creator>
<dc:creator>Sharpe, B. P.</dc:creator>
<dc:creator>Harrington, J.</dc:creator>
<dc:creator>Izadi, F.</dc:creator>
<dc:creator>Kyle, E.</dc:creator>
<dc:creator>Saunders, J. H.</dc:creator>
<dc:creator>Parsons, S. L.</dc:creator>
<dc:creator>Ritchie, A. A.</dc:creator>
<dc:creator>Clarke, P. A.</dc:creator>
<dc:creator>Collier, P.</dc:creator>
<dc:creator>Garbis, S. D.</dc:creator>
<dc:creator>Rose-Zerilli, M.</dc:creator>
<dc:creator>Grabowska, A. M.</dc:creator>
<dc:creator>Underwood, T. J.</dc:creator>
<dc:date>2020-04-23</dc:date>
<dc:identifier>doi:10.1101/2020.04.21.052647</dc:identifier>
<dc:title><![CDATA[Modulation of the tumour promoting functions of cancer associated fibroblasts by phosphodiesterase type 5 inhibition increases the efficacy of chemotherapy in human preclinical models of esophageal adenocarcinoma.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.22.047522v1?rss=1">
<title>
<![CDATA[
Representation of conscious percept without report in the macaque face patch network 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.22.047522v1?rss=1</link>
<description><![CDATA[
A powerful paradigm to identify the neural correlates of consciousness is binocular rivalry, wherein a constant visual stimulus evokes a varying conscious percept. It has recently been suggested that activity modulations observed during rivalry could represent the act of report rather than the conscious percept itself. Here, we performed single-unit recordings from face patches in macaque inferotemporal (IT) cortex using a no-report paradigm in which the animals conscious percept was inferred from eye movements. We found high proportions of IT neurons represented the conscious percept even without active report. Population activity in single trials, measured using a new 128-site Neuropixels-like electrode, was more weakly modulated by rivalry than by physical stimulus transitions, but nevertheless allowed decoding of the changing conscious percept. These findings suggest that macaque face patches encode both the physical stimulus and the animals conscious visual percept, and the latter encoding does not require active report.
]]></description>
<dc:creator>Hesse, J. K.</dc:creator>
<dc:creator>Tsao, D. Y.</dc:creator>
<dc:date>2020-04-24</dc:date>
<dc:identifier>doi:10.1101/2020.04.22.047522</dc:identifier>
<dc:title><![CDATA[Representation of conscious percept without report in the macaque face patch network]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.04.29.068775v1?rss=1">
<title>
<![CDATA[
Electron tomography visualization of HIV-1 fusion with target cells using fusion inhibitors to trap the pre-hairpin intermediate 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.04.29.068775v1?rss=1</link>
<description><![CDATA[
Fusion of HIV-1 with the membrane of its target cell, an obligate first step in virus infectivity, is mediated by binding of the viral envelope (Env) spike protein to its receptors, CD4 and CCR5/CXCR4, on the cell surface. The process of viral fusion appears to be fast compared with viral egress and has not been visualized by electron microscopy (EM). To capture fusion events for EM, the process must be slowed or stopped by trapping Env-receptor binding at an intermediate stage. Here we describe using fusion inhibitors to trap HIV-1 virions attached to target cells by Envs in an extended pre-hairpin intermediate state. Electron tomography revealed HIV-1 virions bound to TZM-bl cells by 2-4 narrow spokes, with slightly more spokes present when evaluated with mutant virions that lacked the Env cytoplasmic tail. These results represent the first direct visualization of the hypothesized pre-hairpin intermediate and improve our understanding of Env-mediated HIV-1 fusion and infection of host cells.
]]></description>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Gnanapragasam, P. N. P.</dc:creator>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Kay, M. S.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2020-04-30</dc:date>
<dc:identifier>doi:10.1101/2020.04.29.068775</dc:identifier>
<dc:title><![CDATA[Electron tomography visualization of HIV-1 fusion with target cells using fusion inhibitors to trap the pre-hairpin intermediate]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-04-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.02.043554v1?rss=1">
<title>
<![CDATA[
Catalytic cleavage of HEAT and subsequent covalent binding of the tetralone moiety by the SARS-CoV-2 main protease 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.02.043554v1?rss=1</link>
<description><![CDATA[
Here we present the crystal structure of SARS-CoV-2 main protease (Mpro) covalently bound to 2-methyl-1-tetralone. This complex was obtained by co-crystallization of Mpro with HEAT (2-(((4-hydroxyphenethyl)amino)methyl)-3,4-dihydronaphthalen-1(2H)-one) in the framework of a large X-ray crystallographic screening project of Mpro against a drug repurposing library, consisting of 5632 approved drugs or compounds in clinical phase trials. Further investigations showed that HEAT is cleaved by Mpro in an E1cB-like reaction mechanism into 2-methylene-1-tetralone and tyramine. The catalytic Cys145 subsequently binds covalently in a Michael addition to the methylene carbon atom of 2-methylene-1-tetralone. According to this postulated model HEAT is acting in a pro-drug-like fashion. It is metabolized by Mpro, followed by covalent binding of one metabolite to the active site. The structure of the covalent adduct elucidated in this study opens up a new path for developing non-peptidic inhibitors.
]]></description>
<dc:creator>Günther, S.</dc:creator>
<dc:creator>Reinke, P. Y. A.</dc:creator>
<dc:creator>Oberthuer, D.</dc:creator>
<dc:creator>Yefanov, O.</dc:creator>
<dc:creator>Ginn, H.</dc:creator>
<dc:creator>Meier, S.</dc:creator>
<dc:creator>Lane, T. J.</dc:creator>
<dc:creator>Lorenzen, K.</dc:creator>
<dc:creator>Gelisio, L.</dc:creator>
<dc:creator>Brehm, W.</dc:creator>
<dc:creator>Dunkel, I.</dc:creator>
<dc:creator>Domaracky, M.</dc:creator>
<dc:creator>Saouane, S.</dc:creator>
<dc:creator>Lieske, J.</dc:creator>
<dc:creator>Ehrt, C.</dc:creator>
<dc:creator>Koua, F.</dc:creator>
<dc:creator>Tolstikova, A.</dc:creator>
<dc:creator>White, T. A.</dc:creator>
<dc:creator>Groessler, M.</dc:creator>
<dc:creator>Fleckenstein, H.</dc:creator>
<dc:creator>Trost, F.</dc:creator>
<dc:creator>Galchenkova, M.</dc:creator>
<dc:creator>Gevorkov, Y.</dc:creator>
<dc:creator>Li, C.</dc:creator>
<dc:creator>Awel, S.</dc:creator>
<dc:creator>Peck, A.</dc:creator>
<dc:creator>Xavier, P. L.</dc:creator>
<dc:creator>Barthelmess, M.</dc:creator>
<dc:creator>Schlünzen, F.</dc:creator>
<dc:creator>Werner, N.</dc:creator>
<dc:creator>Andaleeb, H.</dc:creator>
<dc:creator>Ullah, N.</dc:creator>
<dc:creator>Falke, S.</dc:creator>
<dc:creator>Franca, B. A.</dc:creator>
<dc:creator>Schwinzer, M.</dc:creator>
<dc:creator>Brognaro, H.</dc:creator>
<dc:creator>Seychell, B.</dc:creator>
<dc:creator>Gieseler, H.</dc:creator>
<dc:creator>Melo, D.</dc:creator>
<dc:creator>Zaitsev-Doyle, J. J.</dc:creator>
<dc:creator>Norton-Baker, B.</dc:creator>
<dc:creator>Knoska, J.</dc:creator>
<dc:creator>Esperanza, G.</dc:creator>
<dc:creator>Mashhour, A. R.</dc:creator>
<dc:creator>G</dc:creator>
<dc:date>2020-05-04</dc:date>
<dc:identifier>doi:10.1101/2020.05.02.043554</dc:identifier>
<dc:title><![CDATA[Catalytic cleavage of HEAT and subsequent covalent binding of the tetralone moiety by the SARS-CoV-2 main protease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.07.082883v1?rss=1">
<title>
<![CDATA[
Rising through the Ranks: Seasonal and Diel Patterns of Marine Viruses 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.07.082883v1?rss=1</link>
<description><![CDATA[
Virus-microbe interactions have been studied in great molecular details for many years in cultured model systems, yielding a plethora of knowledge on how viruses use and manipulate host machinery. Since the advent of molecular techniques and high-throughput sequencing, viruses have been deemed the most abundant organisms on earth and methods such as co-occurrence, nucleotide composition and other statistical frameworks have been widely used to infer virus-microbe interactions, overcoming the limitations of culturing methods. However, their accuracy and relevance is still debatable, as co-occurrence does not necessarily mean interaction. Here, we introduce an ecological perspective of marine viral communities and potential interaction with their hosts, using analyses that make no prior assumptions on specific virus-host pairs. By size fractioning water samples into "free viruses" and "microbes" (i.e. also viruses inside or attached to their hosts) and looking at how viral groups abundance changes over time along both fractions, we show that the viral community is undergoing a change in rank abundance across seasons, suggesting a seasonal succession of viruses in the Red Sea. We use abundance patterns in the different size fractions to classify viral populations, indicating potential diverse interactions with their hosts and potential differences in life history traits between major viral groups. Finally, we show hourly resolved variations of intracellular abundance of similar viral groups, which might indicate differences in their infection cycles or metabolic capacities.
]]></description>
<dc:creator>Hevroni, G.</dc:creator>
<dc:creator>Flores-Uribe, J.</dc:creator>
<dc:creator>Beja, O.</dc:creator>
<dc:creator>Philosof, A.</dc:creator>
<dc:date>2020-05-07</dc:date>
<dc:identifier>doi:10.1101/2020.05.07.082883</dc:identifier>
<dc:title><![CDATA[Rising through the Ranks: Seasonal and Diel Patterns of Marine Viruses]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.11.089839v1?rss=1">
<title>
<![CDATA[
MapA, a second large RTX adhesin, contributes to biofilm formation by Pseudomonas fluorescens 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.11.089839v1?rss=1</link>
<description><![CDATA[
Mechanisms by which cells attach to a surface and form a biofilm are diverse and differ greatly between organisms. The Gram-negative, Gammaproteobacterium Pseudomonas fluorescens attaches to a surface through the localization of the large type 1-secreted RTX adhesin LapA to the outer surface of the cell. LapA localization to the cell surface is controlled by the activities of a periplasmic protease, LapG and an inner-membrane spanning cyclic di-GMP responsive effector protein, LapD. A previous study identified a second, LapA-like protein encoded in the P. fluorescens Pf0-1 genome: Pfl01_1463. However, deletion of this gene had no discernible phenotype under our standard laboratory growth conditions. Here, we identified specific growth conditions wherein, Pfl01_1463, hereafter called MapA (Medium Adhesion Protein A) is a functional adhesin contributing to biofilm formation. This adhesin, like LapA, appears to be secreted through a Lap-related type 1 secretion machinery. We show MapA involvement in biofilm formation is also controlled by LapD and LapG, and that the differing roles of LapA and MapA in biofilm formation are achieved, at least in part, through the differences in the sequences of the two adhesins and their differential, cyclic di-GMP-dependent transcriptional regulation. This differential regulation appears to lead to different distributions of the expression of lapA and mapA within a biofilm. Our data indicate that the mechanisms by which a cell forms a biofilm and the components of a biofilm matrix can differ depending on growth conditions in the biofilm.

ImportanceAdhesins are critical for the formation and maturation of bacterial biofilms. We identify a second adhesin in P. fluorescens, called MapA, which appears to play a role in biofilm maturation and whose regulation is distinct from the previously reported LapA adhesin, which is critical for biofilm initiation. Analysis of bacterial adhesins show that LapA-like and MapA-like adhesins are found broadly in Pseudomonads and related organisms, indicating that the utilization of different suites of adhesins may be broadly important in the Gammaproteobacteria.
]]></description>
<dc:creator>Collins, A. J.</dc:creator>
<dc:creator>Pastora, A. B.</dc:creator>
<dc:creator>Smith, T. J.</dc:creator>
<dc:creator>Dahlstrom, K. M.</dc:creator>
<dc:creator>O'Toole, G.</dc:creator>
<dc:date>2020-05-13</dc:date>
<dc:identifier>doi:10.1101/2020.05.11.089839</dc:identifier>
<dc:title><![CDATA[MapA, a second large RTX adhesin, contributes to biofilm formation by Pseudomonas fluorescens]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.12.086132v1?rss=1">
<title>
<![CDATA[
Single Trial Decoding of Movement Intentions Using Functional Ultrasound Neuroimaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.12.086132v1?rss=1</link>
<description><![CDATA[
Brain-machine interfaces (BMI) are powerful devices for restoring function to people living with paralysis. Leveraging significant advances in neurorecording technology, computational power, and understanding of the underlying neural signals, BMI have enabled severely paralyzed patients to control external devices, such as computers and robotic limbs. However, high-performance BMI currently require highly invasive recording techniques, and are thus only available to niche populations. Here, we show that a minimally invasive neuroimaging approach based on functional ultrasound (fUS) imaging can be used to detect and decode movement intention signals usable for BMI. We trained non-human primates to perform memory-guided movements while using epidural fUS imaging to record changes in cerebral blood volume from the posterior parietal cortex - a brain area important for spatial perception, multisensory integration, and movement planning. Using hemodynamic signals acquired during movement planning, we classified left-cued vs. right-cued movements, establishing the feasibility of ultrasonic BMI. These results demonstrate the ability of fUS-based neural interfaces to take advantage of the excellent spatiotemporal resolution, sensitivity, and field of view of ultrasound without breaching the dura or physically penetrating brain tissue.
]]></description>
<dc:creator>Norman, S. L.</dc:creator>
<dc:creator>Maresca, D.</dc:creator>
<dc:creator>Christopoulos, V. N.</dc:creator>
<dc:creator>Griggs, W. S.</dc:creator>
<dc:creator>Demene, C.</dc:creator>
<dc:creator>Tanter, M.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2020-05-14</dc:date>
<dc:identifier>doi:10.1101/2020.05.12.086132</dc:identifier>
<dc:title><![CDATA[Single Trial Decoding of Movement Intentions Using Functional Ultrasound Neuroimaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.12.090068v1?rss=1">
<title>
<![CDATA[
Cell-extracellular matrix interactions in the fluidic phase direct the topology and polarity of self-organized epithelial structures 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.12.090068v1?rss=1</link>
<description><![CDATA[
In vivo, cells are surrounded by extracellular matrix (ECM). To build organs from single cells, it is generally believed that ECM serves as scaffolds to coordinate cell positioning and differentiation. Nevertheless, how cells utilize cell-ECM interactions for the spatiotemporal coordination to different ECM at the tissue scale is not fully understood. Here, using in vitro assay with engineered MDCK cells expressing H2B-mCherry (nucleus) and gp135/Podocalyxin-GFP (apical marker), we show in multi-dimensions that such coordination for epithelial morphogenesis can be determined by cell-soluble ECM interaction in the fluidic phase. The coordination depends on the native topology of ECM components such as sheet-like basement membrane (BM) and type I collagen (COL) fibers: scaffold formed by BM (COL) facilitates a close-ended (open-ended) coordination that leads to the formation of lobular (tubular) epithelium. Further, cells form apicobasal polarity throughout the entire lobule/tubule without a complete coverage of ECM at the basal side, and time-lapse two-photon scanning imaging reveals the polarization occurring early and maintained through the lobular expansion. During polarization, gp135-GFP was converged to the apical surface collectively in the lobular/tubular structures, suggesting possible intercellular communications. Under suspension culture, the polarization was impaired with multi-lumen formation in the tubules, implying the importance of ECM biomechanical microenvironment. Our results suggest a biophysical mechanism for cells to form polarity and coordinate positioning at tissue scale, and in engineering epithelium through cell-soluble ECM interaction and self-assembly.
]]></description>
<dc:creator>Ouyang, M.</dc:creator>
<dc:creator>Yu, J.-Y.</dc:creator>
<dc:creator>Chen, Y.</dc:creator>
<dc:creator>Deng, L.</dc:creator>
<dc:creator>Guo, C.-L.</dc:creator>
<dc:date>2020-05-14</dc:date>
<dc:identifier>doi:10.1101/2020.05.12.090068</dc:identifier>
<dc:title><![CDATA[Cell-extracellular matrix interactions in the fluidic phase direct the topology and polarity of self-organized epithelial structures]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.13.094771v1?rss=1">
<title>
<![CDATA[
In situ structure and organisation of the type IX secretion system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.13.094771v1?rss=1</link>
<description><![CDATA[
The Bacteroidetes type IX secretion system (T9SS) consists of at least 19 components that translocate proteins with a type A or type B C-terminal domain (CTD) signal across the outer membrane. The overall organisation and architecture of this system including how the secretion pore (Sov) interacts with the other components is unknown. We used cryo-electron tomography to obtain the first images of the T9SS including PorK/N rings inside intact Porphyromonas gingivalis cells. Using proteomics, we identified a novel complex between Sov, PorV and PorA and showed that Sov interacts with the PorK/N rings via PorW and a new component PGN_1783. A separate complex comprising the outer membrane {beta}-barrel protein PorP, PorE, and the type B CTD protein PG1035 was also identified. Similarly, the Flavobacterium johnsoniae PorP-like protein, SprF was found bound to the major gliding motility adhesin, SprB. Based on these data, we propose cell surface anchorage for type B CTD proteins to PorP-like proteins and a unique model where the PorK/N rings function as an outer membrane barrier to maintain the close proximity of the translocon to the shuttle and attachment complexes inside the rings, ensuring the harmonized secretion and cell surface attachment of the T9SS substrates.
]]></description>
<dc:creator>Gorasia, D. G.</dc:creator>
<dc:creator>Chreifi, G.</dc:creator>
<dc:creator>Seers, C. A.</dc:creator>
<dc:creator>Butler, C. A.</dc:creator>
<dc:creator>Heath, J. E.</dc:creator>
<dc:creator>Glew, M. D.</dc:creator>
<dc:creator>McBride, M. J.</dc:creator>
<dc:creator>Subramanian, P.</dc:creator>
<dc:creator>Kjaer, A.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Veith, P. D.</dc:creator>
<dc:creator>Reynolds, E. C.</dc:creator>
<dc:date>2020-05-14</dc:date>
<dc:identifier>doi:10.1101/2020.05.13.094771</dc:identifier>
<dc:title><![CDATA[In situ structure and organisation of the type IX secretion system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.17.098806v1?rss=1">
<title>
<![CDATA[
Plasma and Fecal Metabolite Profiles in Autism Spectrum Disorder 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.17.098806v1?rss=1</link>
<description><![CDATA[
Autism Spectrum Disorder (ASD) is a neurodevelopmental condition with hallmark behavioral manifestations including impaired social communication and restricted repetitive behavior. In addition, many affected individuals display metabolic imbalances, immune dysregulation, gastrointestinal (GI) dysfunction, and altered gut microbiome compositions. We sought to better understand non-behavioral features of ASD by determining molecular signatures in peripheral tissues. Herein, we present the untargeted metabolome of 231 plasma and 97 fecal samples from a large cohort of children with ASD and typically developing (TD) controls. Differences in lipid, amino acid, and xenobiotic metabolism discriminate ASD and TD samples. We reveal correlations between specific metabolite profiles and clinical behavior scores, and identify metabolites particularly associated with GI dysfunction in ASD. These findings support a connection between GI physiology, metabolism, and complex behavioral traits, and may advance discovery and development of molecular biomarkers for ASD.
]]></description>
<dc:creator>Needham, B. D.</dc:creator>
<dc:creator>Adame, M. D.</dc:creator>
<dc:creator>Serena, G.</dc:creator>
<dc:creator>Rose, D. R.</dc:creator>
<dc:creator>Preston, G. M.</dc:creator>
<dc:creator>Conrad, M. C.</dc:creator>
<dc:creator>Campbell, A. S.</dc:creator>
<dc:creator>Donabedian, D. H.</dc:creator>
<dc:creator>Fasano, A.</dc:creator>
<dc:creator>Ashwood, P.</dc:creator>
<dc:creator>Mazmanian, S. D.</dc:creator>
<dc:date>2020-05-19</dc:date>
<dc:identifier>doi:10.1101/2020.05.17.098806</dc:identifier>
<dc:title><![CDATA[Plasma and Fecal Metabolite Profiles in Autism Spectrum Disorder]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.19.100214v1?rss=1">
<title>
<![CDATA[
log(x+1)* and log(1+x)* 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.19.100214v1?rss=1</link>
<description><![CDATA[
Single-cell RNA-seq technologies have been successfully employed over the past decade to generate many high resolution cell atlases. These have proved invaluable in recent efforts aimed at understanding the cell type specificity of host genes involved in SARS-CoV-2 infections. While single-cell atlases are based on well-sampled highly-expressed genes, many of the genes of interest for understanding SARS-CoV-2 can be expressed at very low levels. Common assumptions underlying standard single-cell analyses dont hold when examining low-expressed genes, with the result that standard workflows can produce misleading results.

Key PointsLowly expressed genes in single-cell RNA-seq can be easliy misanalyzed.
log(1+x) count normalization introduces errors for lowly expressed genes
The average log(1+x) expression differs considerably from log(x) when x is small
An alternative approach is to use the fraction of cells with non-zero expression
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2020-05-19</dc:date>
<dc:identifier>doi:10.1101/2020.05.19.100214</dc:identifier>
<dc:title><![CDATA[log(x+1)* and log(1+x)*]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.19.101196v1?rss=1">
<title>
<![CDATA[
Focused ultrasound excites neurons via mechanosensitive calcium accumulation and ion channel amplification 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.19.101196v1?rss=1</link>
<description><![CDATA[
Ultrasonic neuromodulation has the unique potential to provide non-invasive control of neural activity in deep brain regions with high spatial precision and without chemical or genetic modification. However, the biomolecular and cellular mechanisms by which focused ultrasound excites mammalian neurons have remained unclear, posing significant challenges for the use of this technology in research and potential clinical applications. Here, we show that focused ultrasound excites neurons through a primarily mechanical mechanism mediated by specific calcium-selective mechanosensitive ion channels. The activation of these channels results in a gradual build-up of calcium, which is amplified by calcium- and voltage-gated channels, generating a burst firing response. Cavitation, temperature changes, large-scale deformation, and synaptic transmission are not required for this excitation to occur. Pharmacological and genetic inhibition of specific ion channels leads to reduced responses to ultrasound, while over-expressing these channels results in stronger ultrasonic stimulation. These findings provide a critical missing explanation for the effect of ultrasound on neurons and facilitate the further development of ultrasonic neuromodulation and sonogenetics as unique tools for neuroscience research.
]]></description>
<dc:creator>Yoo, S.</dc:creator>
<dc:creator>Mittelstein, D. R.</dc:creator>
<dc:creator>Hurt, R. C.</dc:creator>
<dc:creator>Lacroix, J. J.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2020-05-22</dc:date>
<dc:identifier>doi:10.1101/2020.05.19.101196</dc:identifier>
<dc:title><![CDATA[Focused ultrasound excites neurons via mechanosensitive calcium accumulation and ion channel amplification]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.19.104828v1?rss=1">
<title>
<![CDATA[
Rapid Tilt-Series Method for Cryo-Electron Tomography: Characterizing Stage Behavior During FISE Acquisition 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.19.104828v1?rss=1</link>
<description><![CDATA[
We and others recently developed rapid tilt-series acquisition methods for cryo-electron tomography on a Titan Krios G3i equipped with a single axis holder and a K-series direct electron detector and showed that one of these, the fast-incremental single exposure (FISE) method, significantly accelerates tilt-series acquisition when compared to traditional methods while preserving the quality of the images. Here, we characterize the behavior of our single axis holder in detail during a FISE experiment to optimally balance data quality with speed. We explain our methodology in detail so others can characterize their own stages, and conclude with recommendations for projects with different resolution goals.
]]></description>
<dc:creator>Chreifi, G.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2020-05-21</dc:date>
<dc:identifier>doi:10.1101/2020.05.19.104828</dc:identifier>
<dc:title><![CDATA[Rapid Tilt-Series Method for Cryo-Electron Tomography: Characterizing Stage Behavior During FISE Acquisition]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.21.108852v1?rss=1">
<title>
<![CDATA[
A workflow for accurate metabarcoding using nanopore MinION sequencing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.21.108852v1?rss=1</link>
<description><![CDATA[
Metabarcoding has become a common approach to the rapid identification of the species composition in a mixed sample. The majority of studies use established short-read high-throughput sequencing platforms. The Oxford Nanopore MinION, a portable sequencing platform, represents a low-cost alternative allowing researchers to generate sequence data in the field. However, a major drawback is the high raw read error rate that can range from 10% to 22%.

To test if the MinION represents a viable alternative to other sequencing platforms we used rolling circle amplification (RCA) to generate full-length consensus DNA barcodes (658bp of cytochrome oxidase I - COI) for a bulk mock sample of 50 aquatic invertebrate species. By applying two different laboratory protocols, we generated two MinION runs that were used to build consensus sequences. We also developed a novel Python pipeline, ASHURE, for processing, consensus building, clustering, and taxonomic assignment of the resulting reads.

We were able to show that it is possible to reduce error rates to a median accuracy of up to 99.3% for long RCA fragments (>45 barcodes). Our pipeline successfully identified all 50 species in the mock community and exhibited comparable sensitivity and accuracy to MiSeq. The use of RCA was integral for increasing consensus accuracy, but it was also the most time-consuming step during the laboratory workflow and most RCA reads were skewed towards a shorter read length range with a median RCA fragment length of up to 1262bp. Our study demonstrates that Nanopore sequencing can be used for metabarcoding but we recommend the exploration of other isothermal amplification procedures to improve consensus length.
]]></description>
<dc:creator>Baloglu, B.</dc:creator>
<dc:creator>Chen, Z.</dc:creator>
<dc:creator>Elbrecht, V.</dc:creator>
<dc:creator>Braukmann, T.</dc:creator>
<dc:creator>MacDonald, S.</dc:creator>
<dc:creator>Steinke, D.</dc:creator>
<dc:date>2020-05-25</dc:date>
<dc:identifier>doi:10.1101/2020.05.21.108852</dc:identifier>
<dc:title><![CDATA[A workflow for accurate metabarcoding using nanopore MinION sequencing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.23.112664v1?rss=1">
<title>
<![CDATA[
Proofreading through spatial gradients 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.23.112664v1?rss=1</link>
<description><![CDATA[
Key enzymatic processes in biology use the nonequilibrium error correction mechanism called kinetic proofreading to enhance their specificity. Kinetic proofreading typically requires several dedicated structural features in the enzyme, such as a nucleotide hydrolysis site and multiple enzyme-substrate conformations that delay product formation. Such requirements limit the applicability and the adaptability of traditional proofreading schemes. Here, we explore an alternative conceptual mechanism of error correction that achieves delays between substrate binding and subsequent product formation by having these events occur at distinct physical locations. The time taken by the enzyme-substrate complex to diffuse from one location to another is leveraged to discard wrong substrates. This mechanism does not require dedicated structural elements on the enzyme, making it easier to overlook in experiments but also making proofreading tunable on the fly. We discuss how tuning the length scales of enzyme or substrate concentration gradients changes the fidelity, speed and energy dissipation, and quantify the performance limitations imposed by realistic diffusion and reaction rates in the cell. Our work broadens the applicability of kinetic proofreading and sets the stage for the study of spatial gradients as a possible route to specificity.
]]></description>
<dc:creator>Galstyan, V.</dc:creator>
<dc:creator>Husain, K.</dc:creator>
<dc:creator>Xiao, F.</dc:creator>
<dc:creator>Murugan, A.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2020-05-24</dc:date>
<dc:identifier>doi:10.1101/2020.05.23.112664</dc:identifier>
<dc:title><![CDATA[Proofreading through spatial gradients]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.27.119909v1?rss=1">
<title>
<![CDATA[
Engineering multiple levels of specificity in an RNA viral vector 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.27.119909v1?rss=1</link>
<description><![CDATA[
Synthetic molecular circuits could provide powerful therapeutic capabilities, but delivering them to specific cell types and controlling them remains challenging. An ideal “smart” viral delivery system would enable controlled release of viral vectors from “sender” cells, conditional entry into target cells based on cell-surface proteins, conditional replication specifically in target cells based on their intracellular protein content, and an evolutionarily robust system that allows viral elimination with drugs. Here, combining diverse technologies and components, including pseudotyping, engineered bridge proteins, degrons, and proteases, we demonstrate each of these control modes in a model system based on the rabies virus. This work shows how viral and protein engineering can enable delivery systems with multiple levels of control to maximize therapeutic specificity.Competing Interest StatementX.J.G, L.S.C., M.S.K., and M.B.E. are inventors on a U.S. patent provisional application related to this work.View Full Text
]]></description>
<dc:creator>Gao, X. J.</dc:creator>
<dc:creator>Chong, L. S.</dc:creator>
<dc:creator>Ince, M. H.</dc:creator>
<dc:creator>Kim, M. S.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:date>2020-05-27</dc:date>
<dc:identifier>doi:10.1101/2020.05.27.119909</dc:identifier>
<dc:title><![CDATA[Engineering multiple levels of specificity in an RNA viral vector]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.28.118398v1?rss=1">
<title>
<![CDATA[
Compensatory ion transport buffers daily protein rhythms to regulate osmotic balance and cellular physiology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.28.118398v1?rss=1</link>
<description><![CDATA[
Between 6-20% of the cellular proteome is under circadian control to tune cell function with cycles of environmental change. For cell viability, and to maintain volume within narrow limits, the osmotic pressure exerted by changes in the soluble proteome must be compensated. The mechanisms and consequences underlying compensation are not known. Here, we show in cultured mammalian cells and in vivo that compensation requires electroneutral active transport of Na+, K+, and Cl- through differential activity of SLC12A family cotransporters. In cardiomyocytes ex vivo and in vivo, compensatory ion fluxes alter their electrical activity at different times of the day. Perturbation of soluble protein abundance has commensurate effects on ion composition and cellular function across the circadian cycle. Thus, circadian regulation of the proteome impacts ion homeostasis with substantial consequences for the physiology of electrically active cells such as cardiomyocytes.
]]></description>
<dc:creator>Stangherlin, A.</dc:creator>
<dc:creator>Wong, D. C. S.</dc:creator>
<dc:creator>Barbiero, S.</dc:creator>
<dc:creator>Watson, J. L.</dc:creator>
<dc:creator>Zeng, A.</dc:creator>
<dc:creator>Seinkmane, E.</dc:creator>
<dc:creator>Chew, S. P.</dc:creator>
<dc:creator>Beale, A. D.</dc:creator>
<dc:creator>Hayter, E. A.</dc:creator>
<dc:creator>Guna, A.</dc:creator>
<dc:creator>Inglis, A.</dc:creator>
<dc:creator>Bartolami, E.</dc:creator>
<dc:creator>Matile, S.</dc:creator>
<dc:creator>Lequeux, N.</dc:creator>
<dc:creator>Pons, T.</dc:creator>
<dc:creator>Day, J.</dc:creator>
<dc:creator>van Ooijen, G.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:creator>Bechtold, D.</dc:creator>
<dc:creator>Derivery, E.</dc:creator>
<dc:creator>Edgar, R. S.</dc:creator>
<dc:creator>Newham, P.</dc:creator>
<dc:creator>O'Neill, J. S.</dc:creator>
<dc:date>2020-05-28</dc:date>
<dc:identifier>doi:10.1101/2020.05.28.118398</dc:identifier>
<dc:title><![CDATA[Compensatory ion transport buffers daily protein rhythms to regulate osmotic balance and cellular physiology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.28.121533v1?rss=1">
<title>
<![CDATA[
Structures of human antibodies bound to SARS-CoV-2 spike reveal common epitopes and recurrent features of antibodies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.28.121533v1?rss=1</link>
<description><![CDATA[
Neutralizing antibody responses to coronaviruses focus on the trimeric spike, with most against the receptor-binding domain (RBD). Here we characterized polyclonal IgGs and Fabs from COVID-19 convalescent individuals for recognition of coronavirus spikes. Plasma IgGs differed in their degree of focus on RBD epitopes, recognition of SARS-CoV, MERS-CoV, and mild coronaviruses, and how avidity effects contributed to increased binding/neutralization of IgGs over Fabs. Electron microscopy reconstructions of polyclonal plasma Fab-spike complexes showed recognition of both S1A and RBD epitopes. A 3.4[A] cryo-EM structure of a neutralizing monoclonal Fab-S complex revealed an epitope that blocks ACE2 receptor-binding on "up" RBDs. Modeling suggested that IgGs targeting these sites have different potentials for inter-spike crosslinking on viruses and would not be greatly affected by identified SARS-CoV-2 spike mutations. These studies structurally define a recurrent anti-SARS-CoV-2 antibody class derived from VH3-53/VH3-66 and similarity to a SARS-CoV VH3-30 antibody, providing criteria for evaluating vaccine-elicited antibodies.
]]></description>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Huey-Tubman, K.</dc:creator>
<dc:creator>Hoffmann, M. A. G.</dc:creator>
<dc:creator>Sharaf, N. G.</dc:creator>
<dc:creator>Hoffman, P. R.</dc:creator>
<dc:creator>Koranda, N.</dc:creator>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>Gaebler, C.</dc:creator>
<dc:creator>Muecksch, F.</dc:creator>
<dc:creator>Cetrulo Lorenzi, J. C.</dc:creator>
<dc:creator>Finkin, S.</dc:creator>
<dc:creator>Hagglof, T.</dc:creator>
<dc:creator>Hurley, A.</dc:creator>
<dc:creator>Millard, K. G.</dc:creator>
<dc:creator>Weisblum, Y.</dc:creator>
<dc:creator>Schmidt, F.</dc:creator>
<dc:creator>Hatziioannou, T.</dc:creator>
<dc:creator>Bieniasz, P. D.</dc:creator>
<dc:creator>Caskey, M.</dc:creator>
<dc:creator>Robbiani, D.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2020-05-29</dc:date>
<dc:identifier>doi:10.1101/2020.05.28.121533</dc:identifier>
<dc:title><![CDATA[Structures of human antibodies bound to SARS-CoV-2 spike reveal common epitopes and recurrent features of antibodies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.01.127712v1?rss=1">
<title>
<![CDATA[
De novo enteric neurogenesis in post-embryonic zebrafish from Schwann cell precursors rather than resident cell types 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.01.127712v1?rss=1</link>
<description><![CDATA[
The enteric nervous system is essential for normal gastrointestinal function, but evidence regarding postnatal enteric neurogenesis is conflicting. Using zebrafish as a model, we explored the origin of enteric neurons that arise in post-embryonic life in normal development and injury, and tested effects of the 5-HT4 receptor agonist, prucalopride.

To assess enteric neurogenesis, all enteric neurons were photoconverted prior to time-lapse imaging to detect emergence of new neurons. Injury was modeled by two-photon laser ablation of enteric neurons. Lineage tracing was performed with neural tube injections of lipophilic dye and with an inducible Sox10-Cre line. Lastly, we tested prucaloprides effect on post-embryonic enteric neurogenesis.

The post-embryonic zebrafish intestine appears to lack resident neurogenic precursors and enteric glia. However, enteric neurogenesis persists post-embryonically during development and after injury. New enteric neurons arise from trunk neural crest-derived Schwann cell precursors. Prucalopride increases enteric neurogenesis in normal development and after injury if exposure occurs prior to injury.

Enteric neurogenesis persists in the post-embryonic period in both normal development and injury, appears to arise from gut-extrinsic Schwann cell precursors, and is promoted by prucalopride.

SUMMARY STATEMENTTrunk crest-derived enteric neurogenesis is poorly understood. We find post-embryonic zebrafish lack resident neuronal precursors yet enteric neurogenesis from trunk crest-derived precursors occurs in development, injury, and is promoted by prucalopride.
]]></description>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>El-Nachef, W. N.</dc:creator>
<dc:date>2020-06-02</dc:date>
<dc:identifier>doi:10.1101/2020.06.01.127712</dc:identifier>
<dc:title><![CDATA[De novo enteric neurogenesis in post-embryonic zebrafish from Schwann cell precursors rather than resident cell types]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.01.128165v1?rss=1">
<title>
<![CDATA[
Scalable, continuous evolution for the generation of diverse enzyme variants encompassing promiscuous activities 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.01.128165v1?rss=1</link>
<description><![CDATA[
Enzyme orthologs sharing identical primary functions can have different promiscuous activities. While it is possible to mine this natural diversity to obtain useful biocatalysts, generating comparably rich ortholog diversity is difficult, as it is the product of deep evolutionary processes occurring in a multitude of separate species and populations. Here, we take a first step in recapitulating the depth and scale of natural ortholog evolution on laboratory timescales. Using a continuous directed evolution platform called OrthoRep, we rapidly evolved the Thermotoga maritima tryptophan synthase β-subunit (TmTrpB) through multi-mutation pathways in many independent replicates, selecting only onTmTrpB’s primary activity (synthesizing L-tryptophan from indole and L-serine). We find that the resulting sequence-diverseTmTrpB variants span a range of substrate profiles useful in industrial biocatalysis and suggest that the depth and scale of evolution that OrthoRep affords will be generally valuable in enzyme engineering and the evolution of new biomolecular functions.Competing Interest StatementC.E.B and F.H.A. are co-founders of Aralez Bio, focusing on the enzymatic synthesis of unnatural amino acids.View Full Text
]]></description>
<dc:creator>Rix, G.</dc:creator>
<dc:creator>Watkins-Dulaney, E. J.</dc:creator>
<dc:creator>Almhjell, P. J.</dc:creator>
<dc:creator>Boville, C. E.</dc:creator>
<dc:creator>Arnold, F. H.</dc:creator>
<dc:creator>Liu, C. C.</dc:creator>
<dc:date>2020-06-02</dc:date>
<dc:identifier>doi:10.1101/2020.06.01.128165</dc:identifier>
<dc:title><![CDATA[Scalable, continuous evolution for the generation of diverse enzyme variants encompassing promiscuous activities]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.05.136879v1?rss=1">
<title>
<![CDATA[
Global landscape of phenazine biosynthesis and biodegradation reveals species-specific colonization patterns in agricultural soils and crop microbiomes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.05.136879v1?rss=1</link>
<description><![CDATA[
Phenazines are natural bacterial antibiotics that can protect crops from disease. However, for most crops it is unknown which producers and specific phenazines are ecologically relevant, and whether phenazine biodegradation can counter their effects. To better understand their ecology, we developed and environmentally-validated a quantitative metagenomic approach to mine for phenazine biosynthesis and biodegradation genes, applying it to >800 soil and plant-associated shotgun-metagenomes. We discover novel producer-crop associations and demonstrate that phenazine biosynthesis is prevalent across habitats and preferentially enriched in rhizospheres, whereas biodegrading bacteria are rare. We validate an association between maize and Dyella japonica, a putative producer abundant in crop microbiomes. D. japonica upregulates phenazine biosynthesis during phosphate limitation and robustly colonizes maize seedling roots. This work provides a global picture of phenazines in natural environments and highlights plant-microbe associations of agricultural potential. Our metagenomic approach may be extended to other metabolites and functional traits in diverse ecosystems.
]]></description>
<dc:creator>Dar, D.</dc:creator>
<dc:creator>Thomashow, L. S.</dc:creator>
<dc:creator>Weller, D. M.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2020-06-05</dc:date>
<dc:identifier>doi:10.1101/2020.06.05.136879</dc:identifier>
<dc:title><![CDATA[Global landscape of phenazine biosynthesis and biodegradation reveals species-specific colonization patterns in agricultural soils and crop microbiomes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.05.137075v1?rss=1">
<title>
<![CDATA[
The Role of the Medial Prefrontal Cortex in Spatial Margin of Safety Calculations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.05.137075v1?rss=1</link>
<description><![CDATA[
Humans, like many other animals, pre-empt danger by moving to locations that maximize their success at escaping future threats. We test the idea that spatial margin of safety (MOS) decisions, a form of pre-emptive avoidance, results in participants placing themselves closer to safer locations when facing more unpredictable threats. Using multivariate pattern analysis on fMRI data collected while subjects engaged in MOS decisions with varying attack location predictability, we show that while the hippocampus encodes MOS decisions across all types of threat, a vmPFC anterior-posterior gradient tracked threat predictability. The posterior vmPFC encoded for more unpredictable threat and showed functional coupling with the amygdala and hippocampus. Conversely, the anterior vmPFC was more active for the more predictable attacks and showed coupling with the striatum. Our findings suggest that when pre-empting danger, the anterior vmPFC may provide a safety signal, possibly via predictable positive outcomes, while the posterior vmPFC drives prospective danger signals.
]]></description>
<dc:creator>Qi, S.</dc:creator>
<dc:creator>Cross, L.</dc:creator>
<dc:creator>Wise, T.</dc:creator>
<dc:creator>Sui, X.</dc:creator>
<dc:creator>O'Doherty, J.</dc:creator>
<dc:creator>Mobbs, d.</dc:creator>
<dc:date>2020-06-08</dc:date>
<dc:identifier>doi:10.1101/2020.06.05.137075</dc:identifier>
<dc:title><![CDATA[The Role of the Medial Prefrontal Cortex in Spatial Margin of Safety Calculations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.08.140426v1?rss=1">
<title>
<![CDATA[
Multiplexed imaging of human tuberculosis granulomas uncovers immunoregulatory features conserved across tissue and blood 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.08.140426v1?rss=1</link>
<description><![CDATA[
Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis that is distinctly characterized by granuloma formation within infected tissues. Granulomas are dynamic and organized immune cell aggregates that limit dissemination, but can also hinder bacterial clearance. Consequently, outcome in TB is influenced by how granuloma structure and composition shift the balance between these two functions. To date, our understanding of what factors drive granuloma function in humans is limited. With this in mind, we used Multiplexed Ion Beam Imaging by Time-of-Flight (MIBI-TOF) to profile 37 proteins in tissues from thirteen patients with active TB disease from the U.S. and South Africa. With this dataset, we constructed a comprehensive tissue atlas where the lineage, functional state, and spatial distribution of 19 unique cell subsets were mapped onto eight phenotypically-distinct granuloma microenvironments. This work revealed an immunosuppressed microenvironment specific to TB granulomas with spatially coordinated co-expression of IDO1 and PD-L1 by myeloid cells and proliferating regulatory T cells. Interestingly, this microenvironment lacked markers consistent with T-cell activation, supporting a myeloid-mediated mechanism of immune suppression. We observed similar trends in gene expression of immunoregulatory proteins in a confirmatory transcriptomic analysis of peripheral blood collected from over 1500 individuals with latent or active TB infection and healthy controls across 29 cohorts spanning 14 countries. Notably, PD-L1 gene expression was found to correlate with TB progression and treatment response, supporting its potential use as a blood-based biomarker. Taken together, this study serves as a framework for leveraging independent cohorts and complementary methodologies to understand how local and systemic immune responses are linked in human health and disease.
]]></description>
<dc:creator>McCaffrey, E. F.</dc:creator>
<dc:creator>Donato, M.</dc:creator>
<dc:creator>Keren, L.</dc:creator>
<dc:creator>Chen, Z.</dc:creator>
<dc:creator>Fitzpatrick, M.</dc:creator>
<dc:creator>Jojic, V.</dc:creator>
<dc:creator>Delmastro, A.</dc:creator>
<dc:creator>Greenwald, N. F.</dc:creator>
<dc:creator>Baranski, A.</dc:creator>
<dc:creator>Graf, W.</dc:creator>
<dc:creator>Bosse, M.</dc:creator>
<dc:creator>Ramdial, P. K.</dc:creator>
<dc:creator>Forgo, E.</dc:creator>
<dc:creator>Van Valen, D.</dc:creator>
<dc:creator>van de Rijn, M.</dc:creator>
<dc:creator>Bendall, S. C.</dc:creator>
<dc:creator>Banaei, N.</dc:creator>
<dc:creator>Steyn, A. J. C.</dc:creator>
<dc:creator>Khatri, P.</dc:creator>
<dc:creator>Angelo, M.</dc:creator>
<dc:date>2020-06-09</dc:date>
<dc:identifier>doi:10.1101/2020.06.08.140426</dc:identifier>
<dc:title><![CDATA[Multiplexed imaging of human tuberculosis granulomas uncovers immunoregulatory features conserved across tissue and blood]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.10.145169v1?rss=1">
<title>
<![CDATA[
The long-distance flight behavior of Drosophila suggests a general model for wind-assisted dispersal in insects. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.10.145169v1?rss=1</link>
<description><![CDATA[
Despite the ecological importance of long-distance dispersal in insects, its underlying mechanistic basis is poorly understood. One critical question is how insects interact with the wind to increase their travel distance as they disperse. To gain insight into dispersal using a species amenable to further investigation using genetic tools, we conducted release-and-recapture experiments in the Mojave Desert using the fruit fly, Drosophila melanogaster. We deployed chemically-baited traps in a 1 km-radius ring around the release site, equipped with machine vision systems that captured the arrival times of flies as they landed. In each experiment, we released between 30,000 and 200,000 flies. By repeating the experiments under a variety of conditions, we were able to quantify the influence of wind on flies’ dispersal behavior. Our results confirm that even tiny fruit flies could disperse ∼15 km in a single flight in still air, and might travel many times that distance in a moderate wind. The dispersal behavior of the flies is well explained by a model in which animals maintain a fixed body orientation relative to celestial cues, actively regulate groundspeed along their body axis, and allow the wind to advect them sideways. The model accounts for the observation that flies actively fan out in all directions in still air, but are increasingly advected downwind as winds intensify. In contrast, our field data do not support a Lévy flight model of dispersal, despite the fact that our experimental conditions almost perfectly match the core assumptions of that theory.Significance Statement Flying insects play a vital role in terrestrial ecosystems, and their decline over the past few decades has been implicated in a collapse of many species that depend upon them for food. By dispersing over large distances, insects transport biomass from one region to another and thus their flight behavior influences ecology on a global scale. Our experiments provide key insight into the dispersal behavior of insects, and suggest that these animals employ a single algorithm that is functionally robust in both still air and under windy conditions. Our results will make it easier to study the ecologically important phenomenon of long-distance dispersal in a genetic model organism, facilitating the identification of cellular and genetic mechanisms.Competing Interest StatementThe authors have declared no competing interest.View Full Text
]]></description>
<dc:creator>Leitch, K.</dc:creator>
<dc:creator>Ponce, F. V.</dc:creator>
<dc:creator>van Breugel, F.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:date>2020-06-11</dc:date>
<dc:identifier>doi:10.1101/2020.06.10.145169</dc:identifier>
<dc:title><![CDATA[The long-distance flight behavior of Drosophila suggests a general model for wind-assisted dispersal in insects.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.14.150599v1?rss=1">
<title>
<![CDATA[
The changing mouse embryo transcriptome at whole tissue and single-cell resolution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.14.150599v1?rss=1</link>
<description><![CDATA[
In mammalian embryogenesis differential gene expression gradually builds the identity and complexity of each tissue and organ system. We systematically quantified mouse polyA-RNA from embryo day E10.5 to birth, sampling 17 whole tissues, enhanced with single-cell measurements for the developing limb. The resulting developmental transcriptome is globally structured by dynamic cytodifferentiation, body-axis and cell-proliferation gene sets, characterized by their promoters transcription factor (TF) motif codes. We decomposed the tissue-level transcriptome using scRNA-seq and found that neurogenesis and haematopoiesis dominate at both the gene and cellular levels, jointly accounting for 1/3 of differential gene expression and over 40% of identified cell types. Integrating promoter sequence motifs with companion ENCODE epigenomic profiles identified a promoter de-repression mechanism unique to neuronal expression clusters and attributable to known and novel repressors. Focusing on the developing limb, scRNA-seq identified 25 known and candidate novel cell types, including progenitor and differentiating states with computationally inferred lineage relationships. We extracted cell type TF networks and complementary sets of candidate enhancer elements by de-convolving whole-tissue IDEAS epigenome chromatin state models. These ENCODE reference data, computed network components and IDEAS chromatin segmentations, are companion resources to the matching epigenomic developmental matrix, available for researchers to further mine and integrate.
]]></description>
<dc:creator>He, P.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>Trout, D.</dc:creator>
<dc:creator>Marinov, G. K.</dc:creator>
<dc:creator>Amrhein, H.</dc:creator>
<dc:creator>Berghella, L.</dc:creator>
<dc:creator>Goh, S.-T.</dc:creator>
<dc:creator>Plajzer-Frick, I.</dc:creator>
<dc:creator>Afzal, V.</dc:creator>
<dc:creator>Pennacchio, L. A.</dc:creator>
<dc:creator>Dickel, D. E.</dc:creator>
<dc:creator>Visel, A.</dc:creator>
<dc:creator>Ren, B.</dc:creator>
<dc:creator>Hardison, R. C.</dc:creator>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Wold, B. J.</dc:creator>
<dc:date>2020-06-14</dc:date>
<dc:identifier>doi:10.1101/2020.06.14.150599</dc:identifier>
<dc:title><![CDATA[The changing mouse embryo transcriptome at whole tissue and single-cell resolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.16.152975v1?rss=1">
<title>
<![CDATA[
Broad gene expression throughout the mouse and marmoset brain after intravenous delivery of engineered AAV capsids 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.16.152975v1?rss=1</link>
<description><![CDATA[
Genetic intervention is increasingly explored as a therapeutic option for debilitating disorders of the central nervous system. The safety and efficacy of gene therapies relies upon expressing a transgene in affected cells while minimizing off-target expression. To achieve organ/cell-type specific targeting after intravenous delivery of viral vectors, we employed a Cre-transgenic-based screening platform for fast and efficient capsid selection, paired with sequential engineering of multiple surface-exposed loops. We identified capsid variants that are enriched in the brain and detargeted from the liver in mice. The improved enrichment in the brain extends to non-human primates, enabling robust, non-invasive gene delivery to the marmoset brain following IV administration. Importantly, the capsids identified display non-overlapping cell-type tropisms within the brain, with one exhibiting high specificity to neurons. The ability to cross the blood-brain barrier with cell-type specificity in rodents and non-human primates enables new avenues for basic research and potential therapeutic interventions unattainable with naturally occurring serotypes.
]]></description>
<dc:creator>Flytzanis, N. C.</dc:creator>
<dc:creator>Goeden, N.</dc:creator>
<dc:creator>Goertsen, D.</dc:creator>
<dc:creator>Cummins, A.</dc:creator>
<dc:creator>Pickel, J.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2020-06-17</dc:date>
<dc:identifier>doi:10.1101/2020.06.16.152975</dc:identifier>
<dc:title><![CDATA[Broad gene expression throughout the mouse and marmoset brain after intravenous delivery of engineered AAV capsids]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.17.157990v1?rss=1">
<title>
<![CDATA[
Team flow is a unique brain state associated with enhanced information integration and neural synchrony 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.17.157990v1?rss=1</link>
<description><![CDATA[
Team flow occurs when a group of people reaches high task engagement while sharing a common goal as in sports teams and music bands. While team flow is a superior enjoyable experience to individuals experiencing flow or regular socialization, the neural basis for such superiority is still unclear. Here, we addressed this question utilizing a music rhythm task and electroencephalogram hyper-scanning. Experimental manipulations held the motor task constant while disrupted the hedonic musical correspondence to blocking flow or occluded the partners body and task feedback to block social interaction. The manipulations effectiveness was confirmed using psychometric ratings and an objective measure for the depth of flow experience through the inhibition of the auditory-evoked potential to a task-irrelevant stimulus. Spectral power analysis revealed higher beta/gamma power specific to team flow at the left temporal cortex. Causal interaction analysis revealed that the left temporal cortex receives information from areas encoding individual flow or socialization. The left temporal cortex was also significantly involved in integrated information at both the intra- and inter-brains levels. Moreover, team flow resulted in enhanced global inter-brain integrated information and neural synchrony. Thus, our report presents neural evidence that team flow results in a distinct brain state and suggests a neurocognitive mechanism by which the brain creates this unique experience.

Data AvailabilityAll data and analysis codes used in the preparation of this article are available at https://osf.io/3b4hp.
]]></description>
<dc:creator>Shehata, M.</dc:creator>
<dc:creator>Cheng, M.</dc:creator>
<dc:creator>Leung, A.</dc:creator>
<dc:creator>Tsuchiya, N.</dc:creator>
<dc:creator>Wu, D.-A.</dc:creator>
<dc:creator>Tseng, C.-h.</dc:creator>
<dc:creator>Nakauchi, S.</dc:creator>
<dc:creator>Shimojo, S.</dc:creator>
<dc:date>2020-06-19</dc:date>
<dc:identifier>doi:10.1101/2020.06.17.157990</dc:identifier>
<dc:title><![CDATA[Team flow is a unique brain state associated with enhanced information integration and neural synchrony]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.18.160689v1?rss=1">
<title>
<![CDATA[
Cryptosporulation in Kurthia spp. forces a rethinking of asporogenesis in Firmicutes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.18.160689v1?rss=1</link>
<description><![CDATA[
Sporulation is a complex morphophysiological process resulting in a cellular structure that is more resistant than the vegetative form. In Firmicutes, this structure is produced within the mother cell, and is called an endospore. Endospore formation is thought to have evolved in the common ancestor of Firmicutes. However, sporulation has apparently been lost in some extant lineages that are defined as asporogenic. We isolated strain 11kri321, a representative of the genus Kurthia, from an oligotrophic geothermal reservoir. While Kurthia spp. is considered to comprise only asporogenic species, strain 11kri321 produced spores. Genomic reconstruction of the sporulation pathway shows elements typical of sporulation in Bacilli, including the signaling for sporulation onset. However, key genes were missing, including those involved in engulfment and dipicolinic acid synthesis. Based on the results for strain 11kri321, sporulation was investigated in other Kurthia strains. Genes involved in signaling, cell division and spore coat formation were detected in three available Kurthia genomes. Moreover, endosporulation was clearly visualized in at least two of the four strains tested. These results show that Kurthia is an endospore-forming Firmicute lineage. However, the genetic background of sporulation in this genus deviates from the known sporulation pathway in Firmicutes and even within Bacilli, suggesting that a revision of the minimal set of genes used for genomic detection of sporulation is required. Based on our findings we propose the term cryptosporulant to refer to putative asporogenic Firmicutes for which a detailed genomic and physiological characterization of sporulating is missing.

ImportanceEndospore-forming Firmicutes include many environmental and medical relevant bacterial clades. In these microorganisms, the ability to produce endospores is essential for survival in the environment and even for pathogenesis. The minimum core of genes required to produce a viable and resistant spore, the distinction between endospore-forming and asporogenic groups, as well as the evolution of sporulation have been a subject of investigation and debate for decades. Here, we demonstrate endosporulation in the genus Kurthia, considered as asporogenic. Morphological, physiological and genomic analyses were undertaken to demonstrate that sporulation is not lost within this lineage. Based on our results we propose a re-examination of the minimal genetic requirements of sporulation and the use of the term cryptosporulant to describe lineages of Firmicutes that have not previously been observed to sporulate, but for which a detailed analysis is still missing.
]]></description>
<dc:creator>Filippidou, S.</dc:creator>
<dc:creator>Fatton, M.</dc:creator>
<dc:creator>Junier, T.</dc:creator>
<dc:creator>Berge, M.</dc:creator>
<dc:creator>Poppleton, D.</dc:creator>
<dc:creator>Blum, T. B.</dc:creator>
<dc:creator>Kaminek, M.</dc:creator>
<dc:creator>Odriozola, A.</dc:creator>
<dc:creator>Blom, J.</dc:creator>
<dc:creator>Johnson, S. L.</dc:creator>
<dc:creator>Abrahams, J. P.</dc:creator>
<dc:creator>Chain, P. S. G.</dc:creator>
<dc:creator>Gribaldo, S.</dc:creator>
<dc:creator>Tocheva, E. I.</dc:creator>
<dc:creator>Zuber, B.</dc:creator>
<dc:creator>Viollier, P. H.</dc:creator>
<dc:creator>Junier, P.</dc:creator>
<dc:date>2020-06-20</dc:date>
<dc:identifier>doi:10.1101/2020.06.18.160689</dc:identifier>
<dc:title><![CDATA[Cryptosporulation in Kurthia spp. forces a rethinking of asporogenesis in Firmicutes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.19.160374v1?rss=1">
<title>
<![CDATA[
A Biodiversity Composition Map of California Derived from Environmental DNA Metabarcoding and Earth Observation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.19.160374v1?rss=1</link>
<description><![CDATA[
Unique ecosystems globally are under threat from ongoing anthropogenic environmental change. Effective conservation management requires more thorough biodiversity surveys that can reveal system-level patterns and that can be applied rapidly across space and time. We offer a way to use environmental DNA, community science and remote sensing together as methods to reduce the discrepancy between the magnitude of change and historical approaches to measure it. Taking advantages of modern ecological models, we integrate environmental DNA and Earth observations to evaluate regional biodiversity patterns for a snapshot of time, and provide critical community-level characterization. We collected 278 samples in Spring 2017 from coastal, shrub and lowland forest sites in California, a large-scale biodiversity hotspot. We applied gradient forest to model 915 family occurrences and community composition together with environmental variables and multi-scalar habitat classifications to produce a statewide biodiversity-based map. 16,118 taxonomic entries recovered were associated with environmental variables to test their predictive strength on alpha, beta, and zeta diversity. Local habitat classification was diagnostic of community composition, illuminating a characteristic of biodiversity hotspots. Using gradient forest models, environmental variables predicted 35% of the variance in eDNA patterns at the family level, with elevation, sand percentage, and greenness (NDVI32) as the top predictors. This predictive power was higher than we found in published literature at global scale. In addition to this indication of substantial environmental filtering, we also found a positive relationship between environmentally predicted families and their numbers of biotic interactions. In aggregate, these analyses showed that strong eDNA community-environment correlation is a general characteristic of temperate ecosystems, and may explain why communities easily destabilize under disturbances. Our study provides the first example of integrating citizen science based eDNA with biodiversity mapping across the tree of life, with promises to produce large scale, high resolution assessments that promote a more comprehensive and predictive understanding of the factors that influence biodiversity and enhance its maintenance.
]]></description>
<dc:creator>Lin, M.</dc:creator>
<dc:creator>Simons, A. L.</dc:creator>
<dc:creator>Curd, E. E.</dc:creator>
<dc:creator>Harrigan, R. J.</dc:creator>
<dc:creator>Schneider, F. D.</dc:creator>
<dc:creator>Ruiz-Ramos, D. V.</dc:creator>
<dc:creator>Gold, Z.</dc:creator>
<dc:creator>Osborne, M. G.</dc:creator>
<dc:creator>Shirazi, S.</dc:creator>
<dc:creator>Schweizer, T. M.</dc:creator>
<dc:creator>Moore, T. N.</dc:creator>
<dc:creator>Fox, E. A.</dc:creator>
<dc:creator>Turba, R.</dc:creator>
<dc:creator>Garcia-Vedrenne, A. E.</dc:creator>
<dc:creator>Helman, S. K.</dc:creator>
<dc:creator>Rutledge, K.</dc:creator>
<dc:creator>Mejia, M. P.</dc:creator>
<dc:creator>Munguia Ramos, M. N.</dc:creator>
<dc:creator>Wetzer, R.</dc:creator>
<dc:creator>Pentcheff, D.</dc:creator>
<dc:creator>McTavish, E. J.</dc:creator>
<dc:creator>Dawson, M. N.</dc:creator>
<dc:creator>Shapiro, B.</dc:creator>
<dc:creator>Wayne, R. K.</dc:creator>
<dc:creator>Meyer, R. S.</dc:creator>
<dc:date>2020-06-20</dc:date>
<dc:identifier>doi:10.1101/2020.06.19.160374</dc:identifier>
<dc:title><![CDATA[A Biodiversity Composition Map of California Derived from Environmental DNA Metabarcoding and Earth Observation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.29.128439v1?rss=1">
<title>
<![CDATA[
Discovery of a Cellular Mechanism Regulating Transcriptional Noise 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.29.128439v1?rss=1</link>
<description><![CDATA[
Stochastic fluctuations in gene expression (‘noise’) are often considered detrimental but, in other fields, fluctuations are harnessed for benefit (e.g., ‘dither’ or amplification of thermal fluctuations to accelerate chemical reactions). Here, we find that DNA base-excision repair amplifies transcriptional noise, generating increased cellular plasticity and facilitating reprogramming. The DNA-repair protein Apex1 recognizes modified nucleoside substrates to amplify expression noise—while homeostatically maintaining mean levels of expression— for virtually all genes across the transcriptome. This noise amplification occurs for both naturally occurring base modifications and unnatural base analogs. Single-molecule imaging shows amplified noise originates from shorter, but more intense, transcriptional bursts that occur via increased DNA supercoiling which first impedes and then accelerates transcription, thereby maintaining mean levels. Strikingly, homeostatic noise amplification potentiates fate-conversion signals during cellular reprogramming. These data suggest a functional role for the observed occurrence of modified bases within DNA in embryonic development and disease.Competing Interest StatementThe authors have declared no competing interest.View Full Text
]]></description>
<dc:creator>Desai, R.</dc:creator>
<dc:creator>Hansen, M. M. K.</dc:creator>
<dc:creator>Martin, B.</dc:creator>
<dc:creator>Yu, C.</dc:creator>
<dc:creator>Ding, S.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Weinberger, L. S.</dc:creator>
<dc:date>2020-06-30</dc:date>
<dc:identifier>doi:10.1101/2020.06.29.128439</dc:identifier>
<dc:title><![CDATA[Discovery of a Cellular Mechanism Regulating Transcriptional Noise]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.02.183590v1?rss=1">
<title>
<![CDATA[
Developmental, cellular, and biochemical basis of transparency in the glasswing butterfly Greta oto 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.02.183590v1?rss=1</link>
<description><![CDATA[
Numerous species of Lepidoptera have transparent wings, which often possess scales of altered morphology and reduced size, and the presence of membrane surface nanostructures that dramatically reduce reflection. Optical properties and anti-reflective nanostructures have been characterized for several  clearwing Lepidoptera, but the developmental basis of wing transparency is unknown. We apply confocal and electron microscopy to create a developmental time-series in the glasswing butterfly, Greta oto, comparing transparent and non-transparent wing regions. We find that scale precursor cell density is reduced in transparent regions, and cytoskeletal organization differs between flat scales in opaque regions, and thin, bristle-like scales in transparent regions. We also reveal that sub-wavelength nanopillars on the wing membrane are wax-based, derive from wing epithelial cells and their associated microvillar projections, and demonstrate their role in enhancing-anti-reflective properties. These findings provide insight into morphogenesis of naturally organized micro- and nanostructures and may provide bioinspiration for new anti-reflective materials.
]]></description>
<dc:creator>Pomerantz, A. F.</dc:creator>
<dc:creator>Siddique, R. H.</dc:creator>
<dc:creator>Cash, E. I.</dc:creator>
<dc:creator>Kishi, Y.</dc:creator>
<dc:creator>Pinna, C.</dc:creator>
<dc:creator>Hammar, K.</dc:creator>
<dc:creator>Gomez, D.</dc:creator>
<dc:creator>Elias, M.</dc:creator>
<dc:creator>Patel, N. H.</dc:creator>
<dc:date>2020-07-02</dc:date>
<dc:identifier>doi:10.1101/2020.07.02.183590</dc:identifier>
<dc:title><![CDATA[Developmental, cellular, and biochemical basis of transparency in the glasswing butterfly Greta oto]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.04.187286v1?rss=1">
<title>
<![CDATA[
Evolution of DNA Replication Origin Specification and Gene Silencing Mechanisms 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.04.187286v1?rss=1</link>
<description><![CDATA[
DNA replication in eukaryotic cells initiates from chromosomal locations, called replication origins, that bind the Origin Recognition Complex (ORC) prior to S phase. Origin establishment is guided by well-defined DNA sequence motifs in Saccharomyces cerevisiae and some other budding yeasts, but most eukaryotes lack sequence-specific origins. At present, the mechanistic and evolutionary reasons for this difference are unclear. A 3.9 Å structure of S. cerevisiae ORC-Cdc6-Cdt1-Mcm2-7 (OCCM) bound to origin DNA revealed, among other things, that a loop within Orc2 inserts into a DNA minor groove and an α-helix within Orc4 inserts into a DNA major groove1. We show that this Orc4 α-helix mediates the sequence-specificity of origins in S. cerevisiae. Specifically, mutations were identified within this α-helix that alter the sequence-dependent activity of individual origins as well as change global genomic origin firing patterns. This was accomplished using a massively parallel origin selection assay analyzed using a custom mutual-information-based modeling approach and a separate analysis of whole-genome replication profiling and statistics. Interestingly, the sequence specificity of DNA replication initiation, as mediated by the Orc4 α-helix, has evolved in close conjunction with the gain of ORC-Sir4-mediated gene silencing and the loss of RNA interference.Competing Interest StatementThe authors have declared no competing interest.View Full Text
]]></description>
<dc:creator>Hu, Y.</dc:creator>
<dc:creator>Tareen, A.</dc:creator>
<dc:creator>Sheu, Y.-J.</dc:creator>
<dc:creator>Ireland, W. T. T.</dc:creator>
<dc:creator>Speck, C.</dc:creator>
<dc:creator>Li, H.</dc:creator>
<dc:creator>Joshua-Tor, L.</dc:creator>
<dc:creator>Kinney, J. B.</dc:creator>
<dc:creator>Stillman, B.</dc:creator>
<dc:date>2020-07-04</dc:date>
<dc:identifier>doi:10.1101/2020.07.04.187286</dc:identifier>
<dc:title><![CDATA[Evolution of DNA Replication Origin Specification and Gene Silencing Mechanisms]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.06.188003v1?rss=1">
<title>
<![CDATA[
Addressing the pooled amplification paradox with unique molecular identifiers in single-cell RNA-seq 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.06.188003v1?rss=1</link>
<description><![CDATA[
The incorporation of unique molecular identifiers (UMIs) in single-cell RNA-seq assays allows for the removal of amplification bias in the estimation of gene abundances. We show that UMIs can also be used to address a problem resulting from incomplete sequencing of amplified molecules in sequencing libraries that can lead to bias in gene abundance estimates. Our method, called BUTTERFLY, is based on a zero truncated negative binomial estimator and is implemented in the kallisto bustools single-cell RNA-seq workflow. We demonstrate its efficacy using a range of datasets and show that it can invert the relative abundance of certain genes in cases of a pooled amplification paradox.
]]></description>
<dc:creator>Gustafsson, J.</dc:creator>
<dc:creator>Robinson, J.</dc:creator>
<dc:creator>Nielsen, J.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2020-07-06</dc:date>
<dc:identifier>doi:10.1101/2020.07.06.188003</dc:identifier>
<dc:title><![CDATA[Addressing the pooled amplification paradox with unique molecular identifiers in single-cell RNA-seq]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.14.203158v1?rss=1">
<title>
<![CDATA[
Repression of interrupted and intact rDNA by the SUMO pathway in Drosophila melanogaster 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.14.203158v1?rss=1</link>
<description><![CDATA[
Ribosomal RNAs (rRNAs) are essential components of the ribosome and are among the most abundant macromolecules in the cell. To ensure high rRNA level, eukaryotic genomes contain dozens to hundreds of rDNA genes, however, only a fraction of the rRNA genes seems to be active, while others are transcriptionally silent. We found that individual rDNA genes have high level of cell-to-cell heterogeneity in their expression in Drosophila melanogaster. Insertion of heterologous sequences into rDNA leads to repression associated with reduced expression in individual cells and decreased number of cells expressing rDNA with insertions. We found that SUMO (Small Ubiquitin-like Modifier) and SUMO ligase Ubc9 are required for efficient repression of interrupted rDNA units and variable expression of intact rDNA. Disruption of the SUMO pathway abolishes discrimination of interrupted and intact rDNAs and removes cell-to-cell heterogeneity leading to uniformly high expression of individual rDNA in single cells. Our results suggest that the SUMO pathway is responsible for both repression of interrupted units and control of intact rDNA expression.
]]></description>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>Fefelova, E.</dc:creator>
<dc:creator>Ninova, M.</dc:creator>
<dc:creator>Chen, Y.-C. A.</dc:creator>
<dc:creator>Aravin, A.</dc:creator>
<dc:date>2020-07-14</dc:date>
<dc:identifier>doi:10.1101/2020.07.14.203158</dc:identifier>
<dc:title><![CDATA[Repression of interrupted and intact rDNA by the SUMO pathway in Drosophila melanogaster]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.14.203323v1?rss=1">
<title>
<![CDATA[
Binding of guide piRNA triggers methylation of the unstructured N-terminal region of Aub leading to assembly of the piRNA amplification complex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.14.203323v1?rss=1</link>
<description><![CDATA[
Piwi proteins use guide piRNAs to repress selfish genomic elements, protecting the genomic integrity of gametes and ensuring the fertility of animal species. Efficient transposon repression depends on amplification of piRNA guides in the ping-pong cycle, which in Drosophila entails tight cooperation between two Piwi proteins, Aub and Ago3. Here we show that post-translational modification, symmetric dimethylarginine (sDMA), of Aub is essential for piRNA biogenesis, transposon silencing and fertility. Methylation is triggered by loading of a piRNA guide into Aub, which exposes its unstructured N-terminal region to the PRMT5 methylosome complex. Thus, sDMA modification is a signal that Aub is loaded with piRNA guide. Amplification of piRNA in the ping-pong cycle requires assembly of a tertiary complex scaffolded by Krimper, which simultaneously binds the N-terminal regions of Aub and Ago3. To promote generation of new piRNA, Krimp uses its two Tudor domains to bind Aub and Ago3 in opposite modification and piRNA-loading states. Our results reveal that post-translational modifications in unstructured regions of Piwi proteins and their binding by Tudor domains that are capable of discriminating between modification states is essential for piRNA biogenesis and silencing.

HighlightsO_LIsDMA modification of Aub is essential for ping-pong cycle, transposon silencing and fertility.
C_LIO_LIpiRNA loading triggers Aub sDMA modification by exposing its unstructured N terminal region to the methylosome complex.
C_LIO_LIA single molecule of Krimp simultaneously binds piRNA-bound Aub and empty Ago3 to assemble ping-pong complex.
C_LIO_LIThe distinct structure of two Tudor domains of Krimp ensures binding of Ago3 and Aub in opposite modification and piRNA-loading states.
C_LI
]]></description>
<dc:creator>Huang, X.</dc:creator>
<dc:creator>Hu, H.</dc:creator>
<dc:creator>Webster, A.</dc:creator>
<dc:creator>Zou, F.</dc:creator>
<dc:creator>Du, J.</dc:creator>
<dc:creator>Fejes Toth, K.</dc:creator>
<dc:creator>Aravin, A.</dc:creator>
<dc:creator>Li, S.</dc:creator>
<dc:date>2020-07-14</dc:date>
<dc:identifier>doi:10.1101/2020.07.14.203323</dc:identifier>
<dc:title><![CDATA[Binding of guide piRNA triggers methylation of the unstructured N-terminal region of Aub leading to assembly of the piRNA amplification complex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.16.205153v1?rss=1">
<title>
<![CDATA[
Characterizing the diverse cells that associate with the developing commissures of the zebrafish forebrain 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.16.205153v1?rss=1</link>
<description><![CDATA[
During embryonic development of bilateral organisms, neurons send axons across the midline at specific points to connect the two halves of the nervous system with a commissure. Little is known about the cells at the midline that facilitate this tightly regulated process. We exploit the con served process of vertebrate embryonic development in the zebrafish model system to elucidate the identity of cells at the midline that may facilitate postoptic (POC) and anterior commissure (AC) development. We have discovered that three differentgfap+ astroglial cell morphologies persist in contact with pathfinding axons throughout commissure formation. Similarly, olig2+ progenitor cells occupy delineated portions of the postoptic and anterior commissures. These early olig2+ progenitors demonstrate glial-like morphologies despite the lack of a myelination marker. Moreover, we conclude that both the gfap+ and olig2+progenitor cells give rise to neuronal populations in both the telencephalon and diencephalon. Interestingly, these varied cell populations showed significant developmental heterochrony between the telencephalon and diencephalon. Lastly, we also showed that fli1a+ mesenchymal cells migrate along the presumptive commissure regions before and during midline axon crossing. Furthermore, following commissure maturation, specific blood vessels formed at the midline of the POC and immediately ventral and parallel to the AC. This comprehensive account of the cellular populations that correlate with the timing and position of commissural axon pathfinding has supported the conceptual modeling and identification of the early forebrain architecture that may be necessary for proper commissure development.
]]></description>
<dc:creator>Schnabl, J.</dc:creator>
<dc:creator>Litz, M. P. H.</dc:creator>
<dc:creator>Schneider, C.</dc:creator>
<dc:creator>PenkoffLidbeck, N.</dc:creator>
<dc:creator>Bashiruddin, S.</dc:creator>
<dc:creator>Schwartz, M. S.</dc:creator>
<dc:creator>Alligood, K.</dc:creator>
<dc:creator>Barresi, M. J. F.</dc:creator>
<dc:date>2020-07-17</dc:date>
<dc:identifier>doi:10.1101/2020.07.16.205153</dc:identifier>
<dc:title><![CDATA[Characterizing the diverse cells that associate with the developing commissures of the zebrafish forebrain]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.18.210294v1?rss=1">
<title>
<![CDATA[
Generation of ordered protein assemblies using rigid three-body fusion 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.18.210294v1?rss=1</link>
<description><![CDATA[
Protein nanomaterial design is an emerging discipline with applications in medicine and beyond. A longstanding design approach uses genetic fusion to join protein homo-oligomer subunits via -helical linkers to form more complex symmetric assemblies, but this method is hampered by linker flexibility and a dearth of geometric solutions. Here, we describe a general computational method that performs rigid three-body fusion of homo-oligomer and spacer building blocks to generate user-defined architectures, while at the same time significantly increasing the number of geometric solutions over typical symmetric fusion. The fusion junctions are then optimized using Rosetta to minimize flexibility. We apply this method to design and test 92 dihedral symmetric protein assemblies from a set of designed homo-dimers and repeat protein building blocks. Experimental validation by native mass spectrometry, small angle X-ray scattering, and negative-stain single-particle electron microscopy confirms the assembly states for 11 designs. Most of these assemblies are constructed from DARPins (designed ankyrin repeat proteins), anchored on one end by -helical fusion and on the other by a designed homo-dimer interface, and we explored their use for cryo-EM structure determination by incorporating DARPin variants selected to bind targets of interest. Although the target resolution was limited by preferred orientation effects, small scaffold size, and the low-order symmetry of these dihedral scaffolds, we found that the dual anchoring strategy reduced the flexibility of the target-DARPIN complex with respect to the overall assembly, suggesting that multipoint anchoring of binding domains could contribute to cryo-EM structure determination of small proteins.
]]></description>
<dc:creator>Vulovic, I.</dc:creator>
<dc:creator>Yao, Q.</dc:creator>
<dc:creator>Park, Y.-J.</dc:creator>
<dc:creator>Courbet, A.</dc:creator>
<dc:creator>Norris, A.</dc:creator>
<dc:creator>Busch, F.</dc:creator>
<dc:creator>Sahasrabuddhe, A.</dc:creator>
<dc:creator>Merten, H.</dc:creator>
<dc:creator>Sahtoe, D. D.</dc:creator>
<dc:creator>Ueda, G.</dc:creator>
<dc:creator>Fallas, J. A.</dc:creator>
<dc:creator>Hsia, Y.</dc:creator>
<dc:creator>Weaver, S. J.</dc:creator>
<dc:creator>Langan, R. A.</dc:creator>
<dc:creator>Pluckthun, A.</dc:creator>
<dc:creator>Wysocki, V. H.</dc:creator>
<dc:creator>Veesler, D.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Baker, D.</dc:creator>
<dc:date>2020-07-19</dc:date>
<dc:identifier>doi:10.1101/2020.07.18.210294</dc:identifier>
<dc:title><![CDATA[Generation of ordered protein assemblies using rigid three-body fusion]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.20.213066v1?rss=1">
<title>
<![CDATA[
Regulated assembly of the ER membrane protein complex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.20.213066v1?rss=1</link>
<description><![CDATA[
The assembly of nascent proteins into multi-subunit complexes is tightly regulated to maintain cellular homeostasis. The ER membrane protein complex (EMC) is an essential insertase that requires seven membrane-spanning and two soluble subunits for function. Here we show that the kinase With no lysine 1 (WNK1), known for its role in hypertension and neuropathy, is required for assembly of the human EMC. WNK1 uses a conserved amphipathic helix to stabilize the soluble subunit, EMC2, by binding to the EMC2-8 interface. Shielding this hydrophobic surface prevents promiscuous interactions of unassembled EMC2 and precludes binding of ubiquitin ligases, permitting assembly. Using biochemical reconstitution, we show that after EMC2 reaches the membrane, its interaction partners within the EMC displace WNK1, and similarly shield its exposed hydrophobic surfaces. This work describes an unexpected role for WNK1 in protein biogenesis, and defines the general requirements of an assembly factor that will apply across the proteome.
]]></description>
<dc:creator>Pleiner, T.</dc:creator>
<dc:creator>Januszyk, K.</dc:creator>
<dc:creator>Tomaleri, G. P.</dc:creator>
<dc:creator>Oania, R. S.</dc:creator>
<dc:creator>Hazu, M.</dc:creator>
<dc:creator>Sweredoski, M. J.</dc:creator>
<dc:creator>Moradian, A.</dc:creator>
<dc:creator>Guna, A.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:date>2020-07-21</dc:date>
<dc:identifier>doi:10.1101/2020.07.20.213066</dc:identifier>
<dc:title><![CDATA[Regulated assembly of the ER membrane protein complex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.22.216887v1?rss=1">
<title>
<![CDATA[
Dynamics and functional roles of splicing factor autoregulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.22.216887v1?rss=1</link>
<description><![CDATA[
Non-spliceosomal splicing factors are essential, conserved regulators of alternative splicing. They provide concentration-dependent control of diverse pre-mRNAs. Many splicing factors direct unproductive splicing of their own pre-mRNAs through negative autoregulation. However, the impact of such feedback loops on splicing dynamics at the single cell level remains unclear. We developed a system to dynamically, quantitatively analyze negative autoregulatory splicing by the SF2 splicing factor in response to perturbations in single HEK293 cells. Here, we show that negative autoregulatory splicing provides critical functions for gene regulation, establishing a ceiling of SF2 protein concentration, reducing cell-cell heterogeneity in SF2 levels, and buffering variation in SF2 transcription. Most importantly, it adapts SF2 splicing activity to variations in demand from other pre-mRNA substrates. A minimal mathematical model of autoregulatory splicing explains these experimentally observed features, and provides values for effective biochemical parameters. These results reveal the unique functional roles that splicing negative autoregulation plays in homeostatically regulating transcriptional programs.
]]></description>
<dc:creator>Ding, F.</dc:creator>
<dc:creator>Su, C.</dc:creator>
<dc:creator>Chow, K.-H. K.</dc:creator>
<dc:creator>Elowitz, M.</dc:creator>
<dc:date>2020-07-24</dc:date>
<dc:identifier>doi:10.1101/2020.07.22.216887</dc:identifier>
<dc:title><![CDATA[Dynamics and functional roles of splicing factor autoregulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.25.210468v1?rss=1">
<title>
<![CDATA[
Enabling out-of-clinic human immunity studies via single-cell profiling of capillary blood 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.25.210468v1?rss=1</link>
<description><![CDATA[
An individuals immune system is driven by both genetic and environmental factors that vary over time. To better understand the temporal and inter-individual variability of gene expression within distinct immune cell types, we developed a platform that leverages multiplexed single-cell sequencing and out-of-clinic capillary blood extraction to enable simplified, cost-effective profiling of the human immune system across people and time at single-cell resolution. Using the platform, we detect widespread differences in cell type-specific gene expression between subjects that are stable over multiple days.

SummaryIncreasing evidence implicates the immune system in an overwhelming number of diseases, and distinct cell types play specific roles in their pathogenesis.1,2 Studies of peripheral blood have uncovered a wealth of associations between gene expression, environmental factors, disease risk, and therapeutic efficacy.4 For example, in rheumatoid arthritis, multiple mechanistic paths have been found that lead to disease, and gene expression of specific immune cell types can be used as a predictor of therapeutic non-response.12 Furthermore, vaccines, drugs, and chemotherapy have been shown to yield different efficacy based on time of administration, and such findings have been linked to the time-dependence of gene expression in downstream pathways.21,22,23 However, human immune studies of gene expression between individuals and across time remain limited to a few cell types or time points per subject, constraining our understanding of how networks of heterogeneous cells making up each individuals immune system respond to adverse events and change over time.
]]></description>
<dc:creator>Dobreva, T.</dc:creator>
<dc:creator>Brown, D.</dc:creator>
<dc:creator>Park, J. H.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2020-07-26</dc:date>
<dc:identifier>doi:10.1101/2020.07.25.210468</dc:identifier>
<dc:title><![CDATA[Enabling out-of-clinic human immunity studies via single-cell profiling of capillary blood]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.26.222117v1?rss=1">
<title>
<![CDATA[
Predicting the Emergence of SARS-CoV-2 Clades 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.26.222117v1?rss=1</link>
<description><![CDATA[
Evolution is a process of change where mutations in the viral RNA are selected based on their fitness for replication and survival. Given that current phylogenetic analysis of SARS-CoV-2 identifies new viral clades after they exhibit evolutionary selections, one wonders whether we can identify the viral selection and predict the emergence of new viral clades? Inspired by the Kolmogorov complexity concept, we propose a generative complexity (algorithmic) framework capable to analyze the viral RNA sequences by mapping the multiscale nucleotide dependencies onto a state machine, where states represent subsequences of nucleotides and state-transition probabilities encode the higher order interactions between these states. We apply computational learning and classification techniques to identify the active state-transitions and use those as features in clade classifiers to decipher the transient mutations (still evolving within a clade) and stable mutations (typical to a clade). As opposed to current analysis tools that rely on the edit distance between sequences and require sequence alignment, our method is computationally local, does not require sequence alignment and is robust to random errors (substitution, insertions and deletions). Relying on the GISAID viral sequence database, we demonstrate that our method can predict clade emergence, potentially aiding with the design of medications and vaccines.
]]></description>
<dc:creator>Jain, S.</dc:creator>
<dc:creator>Xiao, X.</dc:creator>
<dc:creator>Bogdan, P.</dc:creator>
<dc:creator>Bruck, J.</dc:creator>
<dc:date>2020-07-27</dc:date>
<dc:identifier>doi:10.1101/2020.07.26.222117</dc:identifier>
<dc:title><![CDATA[Predicting the Emergence of SARS-CoV-2 Clades]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.26.222299v1?rss=1">
<title>
<![CDATA[
The Mouse Action Recognition System (MARS): a software pipeline for automated analysis of social behaviors in mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.26.222299v1?rss=1</link>
<description><![CDATA[
The study of naturalistic social behavior requires quantification of animals interactions. This is generally done through manual annotation--a highly time consuming and tedious process. Recent advances in computer vision enable tracking the pose (posture) of freely-behaving animals. However, automatically and accurately classifying complex social behaviors remains technically challenging. We introduce the Mouse Action Recognition System (MARS), an automated pipeline for pose estimation and behavior quantification in pairs of freely interacting mice. We compare MARSs annotations to human annotations and find that MARSs pose estimation and behavior classification achieve human-level performance. We also release the pose and annotation datasets used to train MARS, to serve as community benchmarks and resources. Finally, we introduce the Behavior Ensemble and Neural Trajectory Observatory (BENTO), a graphical user interface for analysis of multimodal neuroscience datasets. Together, MARS and BENTO provide an end-to-end pipeline for behavior data extraction and analysis, in a package that is user-friendly and easily modifiable.
]]></description>
<dc:creator>Segalin, C.</dc:creator>
<dc:creator>Williams, J.</dc:creator>
<dc:creator>Karigo, T.</dc:creator>
<dc:creator>Hui, M.</dc:creator>
<dc:creator>Zelikowsky, M.</dc:creator>
<dc:creator>Sun, J. J.</dc:creator>
<dc:creator>Perona, P.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:creator>Kennedy, A.</dc:creator>
<dc:date>2020-07-27</dc:date>
<dc:identifier>doi:10.1101/2020.07.26.222299</dc:identifier>
<dc:title><![CDATA[The Mouse Action Recognition System (MARS): a software pipeline for automated analysis of social behaviors in mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.27.222729v1?rss=1">
<title>
<![CDATA[
Dorsal raphe dopamine neurons signal motivational salience dependent on internal and external states 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.27.222729v1?rss=1</link>
<description><![CDATA[
The ability to recognize motivationally salient events and respond to them adaptively is critical for survival. Here we tested whether dopamine (DA) neurons in the dorsal raphe nucleus (DRN) contribute to this process. Population recordings of DRNDA neurons during associative learning tasks showed that their activity dynamically tracks salience, developing excitation to both reward- and punishment-paired cues. The DRNDA response to reward-predicting cues was diminished after satiety, suggesting modulation by internal states. DRNDA activity was also greater for unexpected outcomes than for expected outcomes. Two-photon imaging of DRNDA neurons demonstrated that the majority of individual neurons developed activation to reward-predicting cues but not to punishment-predicting cues, which was surprising and qualitatively distinct from the population results. Head-fixation during fear learning abolished the neural response to aversive cues, indicating modulation by behavioral context. Overall, these results suggest that DRNDA neurons encode motivational salience, dependent on internal and external factors.
]]></description>
<dc:creator>Cho, J. R.</dc:creator>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>Kahan, A.</dc:creator>
<dc:creator>Robinson, E.</dc:creator>
<dc:creator>Wagenaar, D. A.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2020-07-27</dc:date>
<dc:identifier>doi:10.1101/2020.07.27.222729</dc:identifier>
<dc:title><![CDATA[Dorsal raphe dopamine neurons signal motivational salience dependent on internal and external states]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.27.223636v1?rss=1">
<title>
<![CDATA[
NEURAL ENCODING OF FELT AND IMAGINED TOUCH WITHIN HUMAN POSTERIOR PARIETAL CORTEX 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.27.223636v1?rss=1</link>
<description><![CDATA[
In the human posterior parietal cortex (PPC), single units encode high-dimensional information with partially mixed representations that enable small populations of neurons to encode many variables relevant to movement planning, execution, cognition, and perception. Here we test whether a PPC neuronal population previously demonstrated to encode visual and motor information is similarly selective in the somatosensory domain. We recorded from 1423 neurons within the PPC of a human clinical trial participant during objective touch presentation and during tactile imagery. Neurons encoded experienced touch with bilateral receptive fields, organized by body part, and covered all tested regions. Tactile imagery evoked body part specific responses that shared a neural substrate with experienced touch. Our results are the first neuron level evidence of touch encoding in human PPC and its cognitive engagement during tactile imagery which may reflect semantic processing, sensory anticipation, and imagined touch.
]]></description>
<dc:creator>Chivukula, S.</dc:creator>
<dc:creator>Zhang, C.</dc:creator>
<dc:creator>Aflalo, T.</dc:creator>
<dc:creator>Jafari, M.</dc:creator>
<dc:creator>Pejsa, K.</dc:creator>
<dc:creator>Pouratian, N.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2020-07-29</dc:date>
<dc:identifier>doi:10.1101/2020.07.27.223636</dc:identifier>
<dc:title><![CDATA[NEURAL ENCODING OF FELT AND IMAGINED TOUCH WITHIN HUMAN POSTERIOR PARIETAL CORTEX]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.31.231860v1?rss=1">
<title>
<![CDATA[
P-bodies are sites of rapid RNA decay during the neural crest epithelial-mesenchymal transition 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.31.231860v1?rss=1</link>
<description><![CDATA[
The epithelial--mesenchymal transition (EMT) drives cellular movements during development to create specialized tissues and structures in metazoans, using mechanisms often coopted during metastasis. Neural crest cells are a multipotent stem cell population that undergo a developmentally regulated EMT and are prone to metastasis in the adult, providing an excellent model to study cell state changes and mechanisms underlying EMT. A hallmark of neural crest EMT during avian development is temporally restricted expression followed by rapid down-regulation of the Wnt antagonist Draxin. Using live RNA imaging, here we demonstrate that rapid clearance of Draxin transcripts is mediated post-transcriptionally via localization to processing bodies (P-bodies), small cytoplasmic granules which are established sites of RNA processing. Contrasting with recent work in immortalized cell lines suggesting that P-bodies are sites of storage rather than degradation, we show that targeted decay of Draxin occurs within P-bodies during neural crest migration. Furthermore, P-body disruption via DDX6 knockdown inhibits not only endogenous Draxin down-regulation but also neural crest EMT in vivo. Together, our data highlight a novel and important role for P-bodies in an intact organismal context--controlling a developmental EMT program via post-transcriptional target degradation.
]]></description>
<dc:creator>Hutchins, E. J.</dc:creator>
<dc:creator>Piacentino, M. L.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:date>2020-08-01</dc:date>
<dc:identifier>doi:10.1101/2020.07.31.231860</dc:identifier>
<dc:title><![CDATA[P-bodies are sites of rapid RNA decay during the neural crest epithelial-mesenchymal transition]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.02.233478v1?rss=1">
<title>
<![CDATA[
BioCRNpyler: Compiling Chemical Reaction Networks from Biomolecular Parts in Diverse Contexts 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.02.233478v1?rss=1</link>
<description><![CDATA[
Biochemical interactions in systems and synthetic biology are often modeled with chemical reaction networks (CRNs). CRNs provide a principled modeling environment capable of expressing a huge range of biochemical processes. In this paper, we present a software toolbox, written in Python, that compiles high-level design specifications represented using a modular library of biochemical parts, mechanisms, and contexts to CRN implementations. This compilation process offers four advantages. First, the building of the actual CRN representation is automatic and outputs Systems Biology Markup Language (SBML) models compatible with numerous simulators. Second, a library of modular biochemical components allows for different architectures and implementations of biochemical circuits to be represented succinctly with design choices propagated throughout the underlying CRN automatically. This prevents the often occurring mismatch between high-level designs and model dynamics. Third, high-level design specification can be embedded into diverse biomolecular environments, such as cell-free extracts and in vivo milieus. Finally, our software toolbox has a parameter database, which allows users to rapidly prototype large models using very few parameters which can be customized later. By using BioCRNpyler, users ranging from expert modelers to novice script-writers can easily build, manage, and explore sophisticated biochemical models using diverse biochemical implementations, environments, and modeling assumptions.

Author summaryThis paper describes a new software package BioCRNpyler (pronounced "Biocompiler") designed to support rapid development and exploration of mathematical models of biochemical networks and circuits by computational biologists, systems biologists, and synthetic biologists. BioCRNpyler allows its users to generate large complex models using very few lines of code in a way that is modular. To do this, BioCRNpyler uses a powerful new representation of biochemical circuits which defines their parts, underlying biochemical mechanisms, and chemical context independently. BioCRNpyler was developed as a Python scripting language designed to be accessible to beginning users as well as easily extendable and customizable for advanced users. Ultimately, we see Biocrnpyler being used to accelerate computer automated design of biochemical circuits and model driven hypothesis generation in biology.
]]></description>
<dc:creator>Poole, W.</dc:creator>
<dc:creator>Pandey, A.</dc:creator>
<dc:creator>Tuza, Z.</dc:creator>
<dc:creator>Shur, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2020-08-03</dc:date>
<dc:identifier>doi:10.1101/2020.08.02.233478</dc:identifier>
<dc:title><![CDATA[BioCRNpyler: Compiling Chemical Reaction Networks from Biomolecular Parts in Diverse Contexts]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.10.244582v1?rss=1">
<title>
<![CDATA[
A Broadly Neutralizing Macaque Monoclonal Antibody Against the HIV-1 V3-Glycan Patch 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.10.244582v1?rss=1</link>
<description><![CDATA[
A small fraction of HIV-1 infected humans develop potent broadly neutralizing antibodies (bNAbs) against HIV-1 that can protect macaques from infection with simian immunodeficiency HIV chimeric virus (SHIV). Similarly, a small number of macaques infected with SHIVs also develop broadly neutralizing serologic activity, but less is known about the nature of these simian antibodies. Here we report on a monoclonal antibody, Ab1485, isolated from a macaque infected with SHIVAD8 that developed broadly neutralizing serologic activity mapping to the V3-glycan region of HIV-1 Env. Ab1485 neutralizes 38.1 % of HIV-1 isolates in a panel of 42 pseudoviruses with a geometric mean IC50 of 0.055 g/ml and SHIVAD8 with an IC50 of 0.028 g/ml. Ab1485 binds to the V3-glycan epitope in a glycan-dependent manner as determined by ELISA and neutralization assays with JRCSF mutant viruses. A 3.5 [A] cryo-electron microscopy structure of Ab1485 in complex with a native-like SOSIP Env trimer showed conserved contacts with the N332gp120 glycan and gp120 GDIR peptide motif, but in a distinct Env-binding orientation relative to human V3/N332gp120 glycan-targeting bNAbs. Finally, intravenous infusion of Ab1485 protected macaques from a high dose intrarectal challenge with SHIVAD8. We conclude that macaques can develop bNAbs against the V3-glycan patch that resemble human V3-glycan bNAbs.

Significance statementRhesus macaques infected with SHIV are an important model for evaluating HIV-1 prevention and therapy strategies and can also be used to evaluate humoral immune responses to candidate HIV-1 vaccines, but whether macaques produce human-like bNAbs has not been evaluated. Like HIV-1 infected humans, 10-20% of the SHIVAD8 challenged macaques develop low levels of neutralizing antibodies, and only one macaque has developed broad and potent serologic neutralizing activity. We have examined the antibody response of this macaque (CE8J) and we report on the cloning and molecular characterization of a bNAb produced in this elite neutralizing non-human primate, its structure bound to an HIV-1 Env trimer, and the implications for development of vaccines targeting the V3-glycan patch of Env.
]]></description>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Gautam, R.</dc:creator>
<dc:creator>Cetrulo Lorenzi, J. C.</dc:creator>
<dc:creator>Mayer, C. T.</dc:creator>
<dc:creator>Oliveira, T. Y.</dc:creator>
<dc:creator>Ramos, V.</dc:creator>
<dc:creator>Cipolla, M.</dc:creator>
<dc:creator>Gordon, K. M.</dc:creator>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Nishimura, Y.</dc:creator>
<dc:creator>Raina, H.</dc:creator>
<dc:creator>Seaman, M. S.</dc:creator>
<dc:creator>Gazumyan, A.</dc:creator>
<dc:creator>Martin, M. A.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Escolano, A.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:date>2020-08-10</dc:date>
<dc:identifier>doi:10.1101/2020.08.10.244582</dc:identifier>
<dc:title><![CDATA[A Broadly Neutralizing Macaque Monoclonal Antibody Against the HIV-1 V3-Glycan Patch]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.11.242081v1?rss=1">
<title>
<![CDATA[
A single-cell method to map higher-order 3D genome organization in thousands of individual cells reveals structural heterogeneity in mouse ES cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.11.242081v1?rss=1</link>
<description><![CDATA[
In eukaryotes, the nucleus is organized into a three dimensional structure consisting of both local interactions such as those between enhancers and promoters, and long-range higher-order structures such as nuclear bodies. This organization is central to many aspects of nuclear function, including DNA replication, transcription, and cell cycle progression. Nuclear structure intrinsically occurs within single cells; however, measuring such a broad spectrum of 3D DNA interactions on a genome-wide scale and at the single cell level has been a great challenge. To address this, we developed single-cell split-pool recognition of interactions by tag extension (scSPRITE), a new method that enables measurements of genome-wide maps of 3D DNA structure in thousands of individual nuclei. scSPRITE maximizes the number of DNA contacts detected per cell enabling high-resolution genome structure maps within each cells and is easy-to-use and cost-effective. scSPRITE accurately detects chromosome territories, active and inactive compartments, topologically associating domains (TADs), and higher-order structures within single cells. In addition, scSPRITE measures cell-to-cell heterogeneity in genome structure at different levels of resolution and shows that TADs are dynamic units of genome organization that can vary between different cells within a population. scSPRITE will improve our understanding of nuclear architecture and its relationship to nuclear function within an individual nucleus from complex cell types and tissues containing a diverse population of cells.
]]></description>
<dc:creator>Arrastia, M. V.</dc:creator>
<dc:creator>Jachowicz, J. W.</dc:creator>
<dc:creator>Ollikainen, N.</dc:creator>
<dc:creator>Curtis, M. S.</dc:creator>
<dc:creator>Lai, C.</dc:creator>
<dc:creator>Quinodoz, S.</dc:creator>
<dc:creator>Selck, D. A.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:creator>Ismagilov, R. F.</dc:creator>
<dc:date>2020-08-12</dc:date>
<dc:identifier>doi:10.1101/2020.08.11.242081</dc:identifier>
<dc:title><![CDATA[A single-cell method to map higher-order 3D genome organization in thousands of individual cells reveals structural heterogeneity in mouse ES cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.13.249730v1?rss=1">
<title>
<![CDATA[
Single position substitution of hairpin pyrrole-imidazole polyamides imparts distinct DNA-binding profiles across the human genome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.13.249730v1?rss=1</link>
<description><![CDATA[
Regulating desired loci in the genome with sequence-specific DNA-binding molecules is a major goal for the development of precision medicine. Pyrrole-imidazole (Py-Im) polyamides are synthetic molecules that can be rationally designed to target specific DNA sequences to both disrupt and recruit transcriptional machinery. While in vitro binding has been extensively studied, in vivo effects are often difficult to predict using current models of DNA binding. Determining the impact of genomic architecture and the local chromatin landscape on polyamide-DNA sequence specificity remains an unresolved question that impedes their effective deployment in vivo. In this report we identified polyamide-DNA interaction sites across the entire genome, by covalently crosslinking and capturing these events in the nuclei of human LNCaP cells. This method, termed COSMIC-seq, confirms the ability of hairpin-polyamides, with similar architectures but differing at a single ring position, to retain in vitro specificities and display distinct genome-wide binding profiles. These results underpin the development of Py-Im polyamides as DNA-targeting molecules that mediate their regulatory or remedial functions at desired genomic loci.
]]></description>
<dc:creator>Finn, P. B.</dc:creator>
<dc:creator>Bhimsaria, D.</dc:creator>
<dc:creator>Ali, A.</dc:creator>
<dc:creator>Eguchi, A.</dc:creator>
<dc:creator>Ansari, A. Z.</dc:creator>
<dc:creator>Dervan, P. B.</dc:creator>
<dc:date>2020-08-14</dc:date>
<dc:identifier>doi:10.1101/2020.08.13.249730</dc:identifier>
<dc:title><![CDATA[Single position substitution of hairpin pyrrole-imidazole polyamides imparts distinct DNA-binding profiles across the human genome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.14.250951v1?rss=1">
<title>
<![CDATA[
Low-cost, bottom-up fabrication of large-scale single-molecule nanoarrays by DNA origami placement 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.14.250951v1?rss=1</link>
<description><![CDATA[
Large-scale nanoarrays of single biomolecules enable high-throughput assays while unmasking the underlying heterogeneity within ensemble populations. Until recently, creating such grids which combine the unique advantages of microarrays and single-molecule experiments (SMEs) has been particularly challenging due to the mismatch between the size of these molecules and the resolution of top-down fabrication techniques. DNA Origami Placement (DOP) combines two powerful techniques to address this issue: (i) DNA origami, which provides a [~] 100-nm self-assembled template for single-molecule organization with 5 nm resolution, and (ii) top-down lithography, which patterns these DNA nanostructures, transforming them into functional nanodevices via large-scale integration with arbitrary substrates. Presently, this technique relies on state-of-the-art infrastructure and highly-trained personnel, making it prohibitively expensive for researchers. Here, we introduce a bench-top technique to create meso-to-macro-scale DNA origami nanoarrays using self-assembled colloidal nanoparticles, thereby circumventing the need for top-down fabrication. We report a maximum yield of 74%, two-fold higher than the statistical limit of 37% imposed on non-specific molecular loading alternatives. Furthermore, we provide a proof-of-principle for the ability of this nanoarray platform to transform traditionally low-throughput, stochastic, single-molecule assays into high-throughput, deterministic ones, without compromising data quality. Our approach has the potential to democratize single-molecule nanoarrays and demonstrates their utility as a tool for biophysical assays and diagnostics.
]]></description>
<dc:creator>Shetty, R. M.</dc:creator>
<dc:creator>Brady, S. R.</dc:creator>
<dc:creator>Rothemund, P. W.</dc:creator>
<dc:creator>Hariadi, R. F.</dc:creator>
<dc:creator>Gopinath, A.</dc:creator>
<dc:date>2020-08-14</dc:date>
<dc:identifier>doi:10.1101/2020.08.14.250951</dc:identifier>
<dc:title><![CDATA[Low-cost, bottom-up fabrication of large-scale single-molecule nanoarrays by DNA origami placement]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.19.258046v1?rss=1">
<title>
<![CDATA[
Coherence Shifts in Attribute Evaluations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.19.258046v1?rss=1</link>
<description><![CDATA[
In five experiments, people repeatedly judged individual options with respect to both overall value and attribute values. When required to choose between two snacks, each differing in two attributes (pleasure and nutrition), peoples assessments of value shifted from pre- to post-choice in the direction that spread the alternatives further apart so as to favor the winner, thereby increasing confidence in the choice. This shift was observed not only for ratings of overall value, but also for each of the two individual attributes. The magnitude of the coherence shift increased with choice difficulty as measured by the difference in initial ratings of overall value for the two options, as well as with a measure of attribute disparity (the degree to which individual attributes "disagree" with one another as to which option is superior). In Experiments 2-5, tasks other than explicit choice generated the same qualitative pattern of value changes, confidence, and response time. These findings support the hypothesis that active consideration of options, whether or not explicitly related to value, automatically refines the mental value representations for the options, which in turn allows them to be more precisely distinguished when later included in a value-based choice set.
]]></description>
<dc:creator>Lee, D.</dc:creator>
<dc:creator>Holyoak, K.</dc:creator>
<dc:date>2020-08-20</dc:date>
<dc:identifier>doi:10.1101/2020.08.19.258046</dc:identifier>
<dc:title><![CDATA[Coherence Shifts in Attribute Evaluations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.22.262956v1?rss=1">
<title>
<![CDATA[
Modular metabolite assembly in C. elegans lysosome-related organelles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.22.262956v1?rss=1</link>
<description><![CDATA[
Signaling molecules derived from attachment of diverse metabolic building blocks to ascarosides play a central role in the life history of C. elegans and other nematodes; however, many aspects of their biogenesis remain unclear. Using comparative metabolomics, we show that a pathway mediating formation of intestinal lysosome-related organelles (LROs) is required for biosynthesis of most modular ascarosides as well as previously undescribed modular glucosides. Similar to modular ascarosides, the modular glucosides are derived from highly selective assembly of moieties from nucleoside, amino acid, neurotransmitter, and lipid metabolism, suggesting that modular glucosides, like the ascarosides, may serve signaling functions. We further show that carboxylesterases that localize to intestinal organelles are required for the assembly of both modular ascarosides and glucosides via ester and amide linkages. Further exploration of LRO function and carboxylesterase homologs in C. elegans and other animals may reveal additional new compound families and signaling paradigms.



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]]></description>
<dc:creator>Le, H. H.</dc:creator>
<dc:creator>Wrobel, C. J.</dc:creator>
<dc:creator>Cohen, S. M.</dc:creator>
<dc:creator>Yu, J.</dc:creator>
<dc:creator>Park, H.</dc:creator>
<dc:creator>Helf, M. J.</dc:creator>
<dc:creator>Curtis, B. J.</dc:creator>
<dc:creator>Rodrigues, P. R.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Schroeder, F. C.</dc:creator>
<dc:date>2020-08-24</dc:date>
<dc:identifier>doi:10.1101/2020.08.22.262956</dc:identifier>
<dc:title><![CDATA[Modular metabolite assembly in C. elegans lysosome-related organelles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.25.266585v1?rss=1">
<title>
<![CDATA[
piRNA-mediated gene regulation and adaptation to sex-specific transposon expression in D. melanogaster male germline 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.25.266585v1?rss=1</link>
<description><![CDATA[
Small non-coding piRNAs act as sequence-specific guides to repress complementary targets in Metazoa. Prior studies in Drosophila ovaries have demonstrated the function of piRNA pathway in transposon silencing and therefore genome defense. However, the ability of piRNA program to respond to different transposon landscape and the role of piRNAs in regulating host gene expression remain poorly understood. Here, we comprehensively analyzed piRNA expression and defined the repertoire of their targets in Drosophila melanogaster testes. Comparison of piRNA programs between sexes revealed sexual dimorphism in piRNA programs that parallel sex-specific transposon expression. Using a novel bioinformatic pipeline, we identified new piRNA clusters and established complex satellites as dual-strand piRNA clusters. While sharing most piRNA clusters, two sexes employ them differentially to combat sex-specific transposon landscape. We found several host genes targeted by piRNAs in testis, including CG12717/pita, a SUMO protease gene. piRNAs encoded on Y chromosome silence pita, but not its paralog, to exert sex- and paralog-specific gene regulation. Interestingly, pita is targeted by endogenous siRNAs in a sibling species, Drosophila mauritiana, suggesting distinct but related silencing strategies invented in recent evolution to regulate a conserved protein-encoding gene.
]]></description>
<dc:creator>Chen, P.</dc:creator>
<dc:creator>Kotov, A. A.</dc:creator>
<dc:creator>Godneeva, B. K.</dc:creator>
<dc:creator>Bazylev, S. S.</dc:creator>
<dc:creator>Olenina, L. V.</dc:creator>
<dc:creator>Aravin, A. A.</dc:creator>
<dc:date>2020-08-25</dc:date>
<dc:identifier>doi:10.1101/2020.08.25.266585</dc:identifier>
<dc:title><![CDATA[piRNA-mediated gene regulation and adaptation to sex-specific transposon expression in D. melanogaster male germline]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.25.266643v1?rss=1">
<title>
<![CDATA[
RDC complex executes a dynamic piRNA program during Drosophila spermatogenesis to safeguard male fertility 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.25.266643v1?rss=1</link>
<description><![CDATA[
piRNAs are small non-coding RNAs that guide the silencing of transposons and other targets in animal gonads. In Drosophila female germline, many piRNA source loci dubbed  piRNA clusters lack hallmarks of active genes and exploit an alternative path for transcription, which relies on the Rhino-Deadlock-Cutoff (RDC) complex. It remains to date unknown how piRNA cluster transcription is regulated in the male germline. We found that components of RDC complex are expressed in male germ cells during early spermatogenesis, from germline stem cells (GSCs) to early spermatocytes. RDC is essential for expression of dual-strand piRNA clusters and transposon silencing in testis; however, it is dispensable for expression of Y-linked Suppressor of Stellate piRNAs and therefore Stellate silencing. Despite intact Stellate repression, rhi mutant males exhibited compromised fertility accompanied by germline DNA damage and GSC loss. Thus, piRNA-guided repression is essential for normal spermatogenesis beyond Stellate silencing. While RDC associates with multiple piRNA clusters in GSCs and early spermatogonia, its localization changes in later stages as RDC concentrates on a single X-linked locus, AT-chX. Dynamic RDC localization is paralleled by changes in piRNA cluster expression, indicating that RDC executes a fluid piRNA program during different stages of spermatogenesis.
]]></description>
<dc:creator>Chen, P.</dc:creator>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>Aravin, A. A.</dc:creator>
<dc:date>2020-08-25</dc:date>
<dc:identifier>doi:10.1101/2020.08.25.266643</dc:identifier>
<dc:title><![CDATA[RDC complex executes a dynamic piRNA program during Drosophila spermatogenesis to safeguard male fertility]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.25.266791v1?rss=1">
<title>
<![CDATA[
Distributed Visual Category Processing Across Medial Superior Temporal and Lateral Intraparietal Cortices 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.25.266791v1?rss=1</link>
<description><![CDATA[
Categorization is an essential cognitive and perceptual process for recognition and decision making. The posterior parietal cortex (PPC), particularly the lateral intraparietal (LIP) area has been suggested to transform visual feature encoding into cognitive or abstract category representations. By contrast, areas closer to sensory input, such as the middle temporal (MT) area, encode stimulus features but not more abstract categorical information during categorization tasks. Here, we compare the contributions of PPC subregions in category computation by recording neuronal activity in the medial superior temporal (MST) and LIP areas during a categorization task. MST is a core motion processing area interconnected with MT, and often considered an intermediate processing stage between MT and LIP. Here we show that MST shows robust decision-correlated category encoding and working memory encoding similar to LIP, suggesting that MST plays a substantial role in cognitive computation, extending beyond its widely recognized role in visual motion processing.
]]></description>
<dc:creator>Zhou, Y.</dc:creator>
<dc:creator>Mohan, K.</dc:creator>
<dc:creator>Freedman, D. J.</dc:creator>
<dc:date>2020-08-25</dc:date>
<dc:identifier>doi:10.1101/2020.08.25.266791</dc:identifier>
<dc:title><![CDATA[Distributed Visual Category Processing Across Medial Superior Temporal and Lateral Intraparietal Cortices]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.25.267435v1?rss=1">
<title>
<![CDATA[
RNA promotes the formation of spatial compartments in the nucleus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.25.267435v1?rss=1</link>
<description><![CDATA[
The nucleus is a highly organized arrangement of RNA, DNA, and protein molecules that are compartmentalized within three-dimensional (3D) structures involved in shared functional and regulatory processes. Although RNA has long been proposed to play a global role in organizing nuclear structure, exploring the role of RNA in shaping nuclear structure has remained a challenge because no existing methods can simultaneously measure RNA-RNA, RNA-DNA, and DNA-DNA contacts within 3D structures. To address this, we developed RNA & DNA SPRITE (RD-SPRITE) to comprehensively map the location of all RNAs relative to DNA and other RNAs. Using this approach, we identify many RNAs that are localized near their transcriptional loci (RNA-DNA) together with other diffusible ncRNAs (RNA-RNA) within higher-order DNA structures (DNA-DNA). These RNA-chromatin compartments span three major classes of nuclear functions: RNA processing (including ribosome biogenesis, mRNA splicing, snRNA biogenesis, and histone mRNA processing), heterochromatin assembly, and gene regulation. More generally, we identify hundreds of ncRNAs that form stable nuclear compartments in spatial proximity to their transcriptional loci. We find that dozens of nuclear compartments require RNA to guide protein regulators into these 3D structures, and focusing on several ncRNAs, we show that these ncRNAs specifically regulate heterochromatin assembly and the expression of genes contained within these compartments. Together, our results demonstrate a unique mechanism by which RNA acts to shape nuclear structure by forming high concentration territories immediately upon transcription, binding to diffusible regulators, and guiding them into spatial compartments to regulate a wide range of essential nuclear functions.
]]></description>
<dc:creator>Quinodoz, S. A.</dc:creator>
<dc:creator>Bhat, P.</dc:creator>
<dc:creator>Ollikainen, N.</dc:creator>
<dc:creator>Jachowicz, J. W.</dc:creator>
<dc:creator>Banerjee, A. K.</dc:creator>
<dc:creator>Chovanec, P.</dc:creator>
<dc:creator>Blanco, M. R.</dc:creator>
<dc:creator>Chow, A.</dc:creator>
<dc:creator>Markaki, Y.</dc:creator>
<dc:creator>Plath, K.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:date>2020-08-25</dc:date>
<dc:identifier>doi:10.1101/2020.08.25.267435</dc:identifier>
<dc:title><![CDATA[RNA promotes the formation of spatial compartments in the nucleus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.30.273920v1?rss=1">
<title>
<![CDATA[
Structural classification of neutralizing antibodies against the SARS-CoV-2 spike receptor-binding domain suggests vaccine and therapeutic strategies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.30.273920v1?rss=1</link>
<description><![CDATA[
The COVID-19 pandemic presents an urgent health crisis. Human neutralizing antibodies (hNAbs) that target the host ACE2 receptor-binding domain (RBD) of the SARS-CoV-2 spike1-5 show therapeutic promise and are being evaluated clincally6-8. To determine structural correlates of SARS-CoV-2 neutralization, we solved 8 new structures of distinct COVID-19 hNAbs5 in complex with SARS-CoV-2 spike trimer or RBD. Structural comparisons allowed classification into categories: (1) VH3-53 hNAbs with short CDRH3s that block ACE2 and bind only to "up" RBDs, (2) ACE2-blocking hNAbs that bind both "up" and "down" RBDs and can contact adjacent RBDs, (3) hNAbs that bind outside the ACE2 site and recognize "up" and "down" RBDs, and (4) Previously-described antibodies that do not block ACE2 and bind only "up" RBDs9. Class 2 comprised four hNAbs whose epitopes bridged RBDs, including a VH3-53 hNAb that used a long CDRH3 with a hydrophobic tip to bridge between adjacent "down" RBDs, thereby locking spike into a closed conformation. Epitope/paratope mapping revealed few interactions with host-derived N-glycans and minor contributions of antibody somatic hypermutations to epitope contacts. Affinity measurements and mapping of naturally-occurring and in vitro-selected spike mutants in 3D provided insight into the potential for SARS-CoV-2 escape from antibodies elicited during infection or delivered therapeutically. These classifications and structural analyses provide rules for assigning current and future human RBD-targeting antibodies into classes, evaluating avidity effects, suggesting combinations for clinical use, and providing insight into immune responses against SARS-CoV-2.
]]></description>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Jette, C. A.</dc:creator>
<dc:creator>Abernathy, M. E.</dc:creator>
<dc:creator>Dam, K.-M. A.</dc:creator>
<dc:creator>Esswein, S. R.</dc:creator>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>Malyutin, A. G.</dc:creator>
<dc:creator>Sharaf, N. G.</dc:creator>
<dc:creator>Huey-Tubman, K. E.</dc:creator>
<dc:creator>Lee, Y. E.</dc:creator>
<dc:creator>Robbiani, D. F.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2020-08-30</dc:date>
<dc:identifier>doi:10.1101/2020.08.30.273920</dc:identifier>
<dc:title><![CDATA[Structural classification of neutralizing antibodies against the SARS-CoV-2 spike receptor-binding domain suggests vaccine and therapeutic strategies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.01.278283v1?rss=1">
<title>
<![CDATA[
Feature-based encoding of face identity by single neurons in the human medial temporal lobe 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.01.278283v1?rss=1</link>
<description><![CDATA[
Neurons in the human amygdala and hippocampus that are selective for the identity of specific people are classically thought to encode a persons identity invariant to visual features (e.g., skin tone, eye shape). However, it remains largely unknown how visual information from higher visual cortical areas is translated into such a semantic representation of an individual person. Here, we show that some amygdala and hippocampal neurons are selective to multiple different unrelated face identities based on shared visual features. The encoded identities form clusters in the representation of a deep neural network trained to recognize faces. Contrary to prevailing views, these neurons thus represent an individuals face with a visual feature-based code rather than one based on association with known concepts. Feature neurons encoded faces regardless of their identity, race, gender, familiarity, or pixel-level visual features; and the region of feature space to which feature neurons are tuned predicted their response to new face stimuli. Our results reveal a new class of neurons that bridge the perception-driven representation of facial features in the higher visual cortex with mnemonic semantic representations in the MTL, which may form the basis for declarative memory.
]]></description>
<dc:creator>Cao, R.</dc:creator>
<dc:creator>Wang, J.</dc:creator>
<dc:creator>Lin, C.</dc:creator>
<dc:creator>Rutishauser, U.</dc:creator>
<dc:creator>Todorov, A.</dc:creator>
<dc:creator>Li, X.</dc:creator>
<dc:creator>Brandmeir, N.</dc:creator>
<dc:creator>Wang, S.</dc:creator>
<dc:date>2020-09-02</dc:date>
<dc:identifier>doi:10.1101/2020.09.01.278283</dc:identifier>
<dc:title><![CDATA[Feature-based encoding of face identity by single neurons in the human medial temporal lobe]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.02.278564v1?rss=1">
<title>
<![CDATA[
Synthetic mammalian signaling circuits for robust cell population control 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.02.278564v1?rss=1</link>
<description><![CDATA[
In multicellular organisms, cells actively sense and control their own population density. Synthetic mammalian quorum sensing circuits could provide insight into principles of population control and extend cell therapies. However, a key challenge is reducing their inherent sensitivity to "cheater" mutations that evade control. Here, we repurposed the plant hormone auxin to enable orthogonal mammalian cell-cell communication and quorum sensing. We designed a paradoxical population control circuit, termed Paradaux, in which auxin stimulates and inhibits net cell growth at different concentrations. This circuit limited population size over extended timescales, of up to 42 days of continuous culture. By contrast, when operating in a non-paradoxical regime, the same cells limited population growth, but were more susceptible to mutational escape. These results establish auxin as a versatile "private" communication system, and demonstrate that paradoxical circuit architectures can provide robust population control.
]]></description>
<dc:creator>Ma, Y.</dc:creator>
<dc:creator>Budde, M. W.</dc:creator>
<dc:creator>Mayalu, M. N.</dc:creator>
<dc:creator>Zhu, J.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:date>2020-09-03</dc:date>
<dc:identifier>doi:10.1101/2020.09.02.278564</dc:identifier>
<dc:title><![CDATA[Synthetic mammalian signaling circuits for robust cell population control]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.07.281501v1?rss=1">
<title>
<![CDATA[
Hmx gene conservation identifies the evolutionary origin of vertebrate cranial ganglia 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.07.281501v1?rss=1</link>
<description><![CDATA[
The evolutionary origin of vertebrates included innovations in sensory processing associated with the acquisition of a predatory lifestyle1. Vertebrates perceive external stimuli through sensory systems serviced by cranial sensory ganglia (CSG) which develop from cranial placodes; however understanding the evolutionary origin of placodes and CSGs is hampered by the gulf between living lineages and difficulty in assigning homology between cell types and structures. Here we use the Hmx gene family to address this question. We show Hmx is a constitutive component of vertebrate CSG development and that Hmx in the tunicate Ciona is able to drive the differentiation program of Bipolar Tail Neurons (BTNs), cells previously thought neural crest homologs2,3. Using Ciona and lamprey transgenesis we demonstrate that a unique, tandemly duplicated enhancer pair regulated Hmx in the stem-vertebrate lineage. Strikingly, we also show robust vertebrate Hmx enhancer function in Ciona, demonstrating that deep conservation of the upstream regulatory network spans the evolutionary origin of vertebrates. These experiments demonstrate regulatory and functional conservation between Ciona and vertebrate Hmx, and confirm BTNs as CSG homologs. Our analysis also identifies derived evolutionary changes, including a genetic basis for secondary simplicity in Ciona and unique regulatory complexity in vertebrates.
]]></description>
<dc:creator>Papadogiannis, V.</dc:creator>
<dc:creator>Parker, H. J.</dc:creator>
<dc:creator>Pennati, A.</dc:creator>
<dc:creator>Patthey, C.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>Shimeld, S. M.</dc:creator>
<dc:date>2020-09-07</dc:date>
<dc:identifier>doi:10.1101/2020.09.07.281501</dc:identifier>
<dc:title><![CDATA[Hmx gene conservation identifies the evolutionary origin of vertebrate cranial ganglia]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.09.284620v1?rss=1">
<title>
<![CDATA[
Targeting Neuroplasticity to Improve Motor Recovery after Stroke 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.09.284620v1?rss=1</link>
<description><![CDATA[
After neurological injury, people develop abnormal patterns of neural activity that limit motor recovery. Traditional rehabilitation, which concentrates on practicing impaired skills, is seldom fully effective. New targeted neuroplasticity (TNP) protocols interact with the CNS to induce beneficial plasticity in key sites and thereby enable wider beneficial plasticity. They can complement traditional therapy and enhance recovery. However, their development and validation is difficult because many different TNP protocols are conceivable, and evaluating even one of them is lengthy, laborious, and expensive. Computational models can address this problem by triaging numerous candidate protocols rapidly and effectively. Animal and human empirical testing can then concentrate on the most promising ones. Here we simulate a neural network of corticospinal neurons that control motoneurons eliciting unilateral finger extension. We use this network to (1) study the mechanisms and patterns of cortical reorganization after a stroke, and (2) identify and parameterize a TNP protocol that improves recovery of extension force. After a simulated stroke, standard training produced abnormal bilateral cortical activation and suboptimal force recovery. To enhance recovery, we interdigitated standard trials with trials in which the teaching signal came from a targeted population of sub-optimized neurons. Targeting neurons in secondary motor areas on 5-20% of the total trials restored lateralized cortical activation and improved recovery of extension force. The results illuminate mechanisms underlying suboptimal cortical activity post-stroke; they enable identification and parameterization of the most promising TNP protocols. By providing initial guidance, computational models could facilitate and accelerate realization of new therapies that improve motor recovery.
]]></description>
<dc:creator>Norman, S. L.</dc:creator>
<dc:creator>Wolpaw, J. R.</dc:creator>
<dc:creator>Reinkensmeyer, D. J.</dc:creator>
<dc:date>2020-09-09</dc:date>
<dc:identifier>doi:10.1101/2020.09.09.284620</dc:identifier>
<dc:title><![CDATA[Targeting Neuroplasticity to Improve Motor Recovery after Stroke]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.11.294058v1?rss=1">
<title>
<![CDATA[
Neural encoding of socially adjusted value during competitive and hazardous foraging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.11.294058v1?rss=1</link>
<description><![CDATA[
In group foraging organisms, optimizing the conflicting demands of competitive food loss and safety is critical. We demonstrate that humans select competition avoidant and risk diluting strategies during foraging depending on socially adjusted value. We formulate a mathematically grounded quantification of socially adjusted value in foraging environments and show using multivariate fMRI analyses that socially adjusted value is encoded by mid-cingulate and ventromedial prefrontal cortices, regions that integrate value and action signals.
]]></description>
<dc:creator>Silston, B.</dc:creator>
<dc:creator>Wise, T.</dc:creator>
<dc:creator>Qi, S.</dc:creator>
<dc:creator>Sui, X.</dc:creator>
<dc:creator>Dayan, P.</dc:creator>
<dc:creator>Mobbs, D.</dc:creator>
<dc:date>2020-09-12</dc:date>
<dc:identifier>doi:10.1101/2020.09.11.294058</dc:identifier>
<dc:title><![CDATA[Neural encoding of socially adjusted value during competitive and hazardous foraging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.16.300319v1?rss=1">
<title>
<![CDATA[
A soluble ACE2 microbody protein fused to a single immunoglobulin Fc domain is a potent inhibitor of SARS-CoV-2 infection in cell culture 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.16.300319v1?rss=1</link>
<description><![CDATA[
Soluble forms of ACE2 have recently been shown to inhibit SARS-CoV-2 infection. We report on an improved soluble ACE2, termed a "microbody" in which the ACE2 ectodomain is fused to Fc domain 3 of the immunoglobulin heavy chain. The protein is smaller than previously described ACE2-Ig Fc fusion proteins and contains an H345A mutation in the ACE2 catalytic active site that inactivates the enzyme without reducing its affinity for the SARS-CoV-2 spike. The disulfide-bonded ACE2 microbody protein inhibited entry of lentiviral SARS-CoV-2 spike protein pseudotyped virus and live SARS-CoV-2 with a potency 10-fold higher than unmodified soluble ACE2 and was active after initial virus binding to the cell. The ACE2 microbody inhibited the entry of ACE2-specific {beta} coronaviruses and viruses with the high infectivity variant D614G spike. The ACE2 microbody may be a valuable therapeutic for COVID-19 that is active against SARS-CoV-2 variants and future coronaviruses that may arise.
]]></description>
<dc:creator>Tada, T.</dc:creator>
<dc:creator>Fan, C.</dc:creator>
<dc:creator>Kaur, R.</dc:creator>
<dc:creator>Stapleford, K. A.</dc:creator>
<dc:creator>Gristick, H.</dc:creator>
<dc:creator>Nimigean, C.</dc:creator>
<dc:creator>Landau, N. R.</dc:creator>
<dc:date>2020-09-17</dc:date>
<dc:identifier>doi:10.1101/2020.09.16.300319</dc:identifier>
<dc:title><![CDATA[A soluble ACE2 microbody protein fused to a single immunoglobulin Fc domain is a potent inhibitor of SARS-CoV-2 infection in cell culture]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.18.298562v1?rss=1">
<title>
<![CDATA[
Challenges in solving structures from radiation-damaged tomograms of protein nanocrystals assessed by simulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.18.298562v1?rss=1</link>
<description><![CDATA[
Structure determination methods are needed to resolve the atomic details that underlie protein function. X-ray crystallography has provided most of our knowledge of protein structure but is constrained by the need for large, well-ordered crystals and the loss of phase information. The rapidly developing methods of serial femtosecond crystallography, micro-electron diffraction, and single-particle reconstruction circumvent the first of these limitations by enabling data collection from nanocrystals or purified proteins. However, the first two methods also suffer from the phase problem, while many proteins fall below the molecular weight threshold required by single-particle reconstruction. Cryo-electron tomography of protein nanocrystals has the potential to overcome these obstacles of mainstream structure determination methods. Here we present a data processing scheme that combines routines from X-ray crystallography and new algorithms we developed to solve structures from tomograms of nanocrystals. This pipeline handles image processing challenges specific to tomographic sampling of periodic specimens and is validated using simulated crystals. We also assess the tolerance of this workflow to the effects of radiation damage. Our simulations indicate a trade-off between a wider tilt-range to facilitate merging data from multiple tomograms and a smaller tilt increment to improve phase accuracy. Since phase errors but not merging errors can be overcome with additional datasets, these results recommend distributing the dose over a wide angular range rather than using a finer sampling interval to solve the protein structure.
]]></description>
<dc:creator>Peck, A.</dc:creator>
<dc:creator>Yao, Q.</dc:creator>
<dc:creator>Brewster, A. S.</dc:creator>
<dc:creator>Zwart, P. H.</dc:creator>
<dc:creator>Heumann, J. M.</dc:creator>
<dc:creator>Sauter, N. K.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2020-09-20</dc:date>
<dc:identifier>doi:10.1101/2020.09.18.298562</dc:identifier>
<dc:title><![CDATA[Challenges in solving structures from radiation-damaged tomograms of protein nanocrystals assessed by simulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.22.308395v1?rss=1">
<title>
<![CDATA[
The structure of the UDP-Glc/GlcNAc 4-epimerase from the human pathogen Campylobacter jejuni 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.22.308395v1?rss=1</link>
<description><![CDATA[
Worldwide, the food-born pathogen Campylobacter jejuni is the leading bacterial source of human gastroenteritis. C. jejuni produces a variety of diverse cell-surface carbohydrates that are essential for pathogenicity. A critical component of these oligo- and polysaccharides is the sugar N-acetylgalactosamine (GalNAc). The sole source of this sugar is the epimerization of UDP-N-acetylglucosamine (GlcNAc), a reaction catalyzed by the enzyme UDP-GlcNAc 4-epimerase (Gne). This enzyme is unique among known bacterial epimerases in that it also catalyzes the equivalent reaction with the non-N-acetylated sugars. Understanding how CjGne catalyzes these various interconversions is critical to designing novel inhibitors of this enzyme. Here, to further the mechanistic understanding we present a 2.0[A] structure of CjGne with its NAD+ co-factor bound. Based on novel features found in the structure we perform a variety of biochemical studies to probe the mechanism and compare these results to another bifunctional epimerase, human GalE. We further show that ebselen, previously identified for inhibition of HsGalE, is active against CjGne, suggesting a route for antibiotic development.
]]></description>
<dc:creator>Yun, H. G.</dc:creator>
<dc:creator>Jang, K.-S.</dc:creator>
<dc:creator>Tanaka, S.</dc:creator>
<dc:creator>Clemons, W. M.</dc:creator>
<dc:date>2020-09-22</dc:date>
<dc:identifier>doi:10.1101/2020.09.22.308395</dc:identifier>
<dc:title><![CDATA[The structure of the UDP-Glc/GlcNAc 4-epimerase from the human pathogen Campylobacter jejuni]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.22.308593v1?rss=1">
<title>
<![CDATA[
Structural biologists, lets mind our colors 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.22.308593v1?rss=1</link>
<description><![CDATA[
In structural biology, most figures of macromolecules are aimed at those well-versed in structure, requiring prior familiarity with scales and commonly used color schemes. Yet, as structural biology becomes democratized with the increasing pace of structure determination, the accessibility of structural data is paramount. Here, we identify three keys, and have written accompanying software plugins, for structural biologists to create figures truer to the hard-won data and clearer across different modes of color vision and to non-expert readers.

O_LIUse perceptually uniform colormaps
C_LIO_LIConsider readers with different modes of color vision
C_LIO_LIBe explicit about scales and color usage
C_LI
]]></description>
<dc:creator>Saladi, S. M.</dc:creator>
<dc:creator>Maggiolo, A. O.</dc:creator>
<dc:creator>Radford, K.</dc:creator>
<dc:creator>Clemons, W. M.</dc:creator>
<dc:date>2020-09-24</dc:date>
<dc:identifier>doi:10.1101/2020.09.22.308593</dc:identifier>
<dc:title><![CDATA[Structural biologists, lets mind our colors]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.23.310680v1?rss=1">
<title>
<![CDATA[
Mechanism of cell polarisation and first lineage segregation in the human embryo 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.23.310680v1?rss=1</link>
<description><![CDATA[
The formation of differential cell lineages in the mammalian blastocyst from the totipotent zygote is crucial for implantation and the success of the whole pregnancy. The first lineage segregation generates the polarised trophectoderm (TE) tissue, which forms the placenta, and the apolar inner cell mass (ICM), which mainly gives rise to all foetal tissues and also the yolk sac1-3. The mechanism underlying this cell fate segregation has been extensively studied in the mouse embryo4,5. However, when and how it takes place in the human embryo remains unclear. Here, using time-lapse imaging and 325 surplus human embryos, we provide a detailed characterisation of morphological events and transcription factor expression and localisation to understand how they lead to the first lineage segregation in human embryogenesis. We show that the first lineage segregation of the human embryo is triggered by cell polarisation that occurs at the 8-cell stage in two sequential steps. In the first step, F-actin becomes apically polarised concomitantly with embryo compaction. In the second step, the Par complex becomes polarised to form the apical cellular domain. Mechanistically, we show that activation of Phospholipase C (PLC) triggers actin polarisation and is therefore essential for apical domain formation, as is the case in mouse embryos6. Finally, we show that, in contrast to the mouse embryo, the key extra-embryonic determinant GATA37,8 is expressed not only in extra-embryonic lineage precursors upon blastocyst formation. However, the cell polarity machinery enhances the expression and nuclear accumulation of GATA3. In summary, our results demonstrate for the first time that cell polarisation reinforces the first lineage segregation in the human embryo.
]]></description>
<dc:creator>Zhu, M.</dc:creator>
<dc:creator>Shahbazi, M. N.</dc:creator>
<dc:creator>Martin, A.</dc:creator>
<dc:creator>Zhang, C.</dc:creator>
<dc:creator>Sozen, B.</dc:creator>
<dc:creator>Borsos, M.</dc:creator>
<dc:creator>Mandelbaum, R. S.</dc:creator>
<dc:creator>Paulson, R. J.</dc:creator>
<dc:creator>Mole, M. A.</dc:creator>
<dc:creator>Esbert, M.</dc:creator>
<dc:creator>Scott, R. T.</dc:creator>
<dc:creator>Campbell, A.</dc:creator>
<dc:creator>Fishel, S.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:creator>Zhao, H.</dc:creator>
<dc:creator>Wu, K.</dc:creator>
<dc:creator>Chen, Z.</dc:creator>
<dc:creator>Seli, E.</dc:creator>
<dc:creator>de los Santos, M. J.</dc:creator>
<dc:creator>Zernicka-Goetz, M.</dc:creator>
<dc:date>2020-09-23</dc:date>
<dc:identifier>doi:10.1101/2020.09.23.310680</dc:identifier>
<dc:title><![CDATA[Mechanism of cell polarisation and first lineage segregation in the human embryo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.24.312025v1?rss=1">
<title>
<![CDATA[
Three-Dimensional Impedance Tomographic Mapping of Metabolically Active Endolumen 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.24.312025v1?rss=1</link>
<description><![CDATA[
Real-time detection of vulnerable atherosclerotic lesions, characterized by a high content of oxidized low-density lipoprotein (oxLDL)-laden macrophages or foam cells, remains an unmet clinical need. While fractional flow reserve (FFR)-guided revascularization in angiographically intermediate stenoses is utilized to assess hemodynamic significance, in vivo detection of oxLDL-rich plaques may provide a new paradigm for treating metabolically unstable lesions. Herein, we have demonstrated endoluminal mapping of lipid-laden lesions using 3-D electrical impedance spectroscopy-derived impedance tomography (EIT) in a pre-clinical swine model. We performed surgical banding of the right carotid arteries of Yucatan mini-pigs, followed by 16 weeks of high-fat diet, to promote the development of lipid-rich lesions. We implemented an intravascular sensor combining an FFR pressure transducer with a 6-point micro-electrode array for electrical impedance spectroscopy (EIS) measurements. 3-D EIT mapping was achieved using an EIS-based reconstruction algorithm. We demonstrated that EIT mapping corresponds to endoluminal histology for oxLDL-laden lesions. We further used computational models to theoretically predict and validate EIS measurements. Thus, our 3-D EIS-derived EIT provides in vivo detection of metabolically active plaques with the goal of guiding optimal intravascular intervention.

One Sentence SummaryThis work demonstrates in vivo mapping of oxidized LDL-laden endolumen by deploying an intravascular dual-sensor to a swine model of atherosclerosis.
]]></description>
<dc:creator>Abiri, P.</dc:creator>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>Huang, Z.-Y.</dc:creator>
<dc:creator>Roustaei, M.</dc:creator>
<dc:creator>Duarte-Vogel, S.</dc:creator>
<dc:creator>Cui, Q.</dc:creator>
<dc:creator>Packard, R. R. S.</dc:creator>
<dc:creator>Ebrahimi, R.</dc:creator>
<dc:creator>Benharash, P.</dc:creator>
<dc:creator>Tai, Y.-C.</dc:creator>
<dc:creator>Hsiai, T. K.</dc:creator>
<dc:date>2020-09-25</dc:date>
<dc:identifier>doi:10.1101/2020.09.24.312025</dc:identifier>
<dc:title><![CDATA[Three-Dimensional Impedance Tomographic Mapping of Metabolically Active Endolumen]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.24.312322v1?rss=1">
<title>
<![CDATA[
Field testing of biohybrid robotic jellyfish to demonstrate enhanced swimming speeds 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.24.312322v1?rss=1</link>
<description><![CDATA[
Biohybrid robotic designs incorporating live animals and self-contained microelectronic systems can leverage the animals own metabolism to reduce power constraints and act as natural chassis and actuators with damage tolerance. Previous work established that biohybrid robotic jellyfish can exhibit enhanced speeds up to 2.8 times their baseline behavior in laboratory environments. However, it remains unknown if the results could be applied in natural, dynamic ocean environments and what factors can contribute to large animal variability. Deploying this system in the coastal waters of Massachusetts, we validate and extend prior laboratory work by demonstrating increases in jellyfish swimming speeds up to 2.3 times greater than their baseline, with absolute swimming speeds up to 6.6 {+/-} 0.3 cm s-1. These experimental swimming speeds are predicted using a hydrodynamic model with morphological and time-dependent input parameters obtained from field experiment videos. The theoretical model can provide a basis to choose specific jellyfish with desirable traits to maximize enhancements from robotic manipulation. With future work to increase maneuverability and incorporate sensors, biohybrid robotic jellyfish can potentially be used track environmental changes in applications for ocean monitoring.
]]></description>
<dc:creator>Xu, N. W.</dc:creator>
<dc:creator>Townsend, J. P.</dc:creator>
<dc:creator>Costello, J. H. H.</dc:creator>
<dc:creator>Colin, S.</dc:creator>
<dc:creator>Gemmell, B.</dc:creator>
<dc:creator>Dabiri, J. O.</dc:creator>
<dc:date>2020-09-25</dc:date>
<dc:identifier>doi:10.1101/2020.09.24.312322</dc:identifier>
<dc:title><![CDATA[Field testing of biohybrid robotic jellyfish to demonstrate enhanced swimming speeds]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.25.312868v1?rss=1">
<title>
<![CDATA[
Intrinsic and extrinsic noise are distinguishable in a synthesis - export - degradation model of mRNA production 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.25.312868v1?rss=1</link>
<description><![CDATA[
Intrinsic and extrinsic noise sources in gene expression, originating respectively from transcriptional stochasticity and from differences between cells, complicate the determination of transcriptional models. In particularly degenerate cases, the two noise sources are altogether impossible to distinguish. However, the incorporation of downstream processing, such as the mRNA splicing and export implicated in gene expression buffering, recovers the ability to identify the relevant source of noise. We report analytical copy-number distributions, discuss the noise sources qualitative effects on lower moments, and provide simulation routines for both models.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2020-09-25</dc:date>
<dc:identifier>doi:10.1101/2020.09.25.312868</dc:identifier>
<dc:title><![CDATA[Intrinsic and extrinsic noise are distinguishable in a synthesis - export - degradation model of mRNA production]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.25.313312v1?rss=1">
<title>
<![CDATA[
A multiscale analysis of early flower development in Arabidopsis provides an integrated view of molecular regulation and growth control 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.25.313312v1?rss=1</link>
<description><![CDATA[
The link between gene regulation and morphogenesis of multicellular organisms is a fundamental problem in biology. We address this question in the floral meristem of Arabidopsis, which generates new tissues and organs through complex changes in growth patterns. Starting from high-resolution time-lapse images, we generated a comprehensive 4-D atlas of early flower development including cell lineage, cellular growth rates and the expression patterns of 28 regulatory genes. This information was introduced in MorphoNet, a web-based open-access platform.

The application of mechanistic computational models indicated that the molecular network based on the literature only explained a minority of the expression patterns. This was substantially improved by adding single regulatory hypotheses for individual genes. We next used the integrated information to correlate growth with the combinatorial expression of multiple genes. This led us to propose a set of hypotheses for the action of individual genes in morphogenesis, not visible by simply correlating gene expression and growth. This identified the central transcription factor LEAFY as a potential regulator of heterogeneous growth, which was supported by quantifying growth patterns in a leafy mutant. By providing an integrated, multiscale view of flower development, this atlas should represent a fundamental step towards mechanistic multiscale-scale models of flower development.
]]></description>
<dc:creator>Refahi, Y.</dc:creator>
<dc:creator>Zardilis, A.</dc:creator>
<dc:creator>Michelin, G.</dc:creator>
<dc:creator>Wightman, R.</dc:creator>
<dc:creator>Leggio, B.</dc:creator>
<dc:creator>Legrand, J.</dc:creator>
<dc:creator>Faure, E.</dc:creator>
<dc:creator>Vachez, L.</dc:creator>
<dc:creator>Armezzani, A.</dc:creator>
<dc:creator>Zhao, F.</dc:creator>
<dc:creator>Das, P.</dc:creator>
<dc:creator>Prunet, N.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:creator>Godin, C.</dc:creator>
<dc:creator>Malandain, G.</dc:creator>
<dc:creator>Jonsson, H.</dc:creator>
<dc:creator>Traas, J.</dc:creator>
<dc:date>2020-09-26</dc:date>
<dc:identifier>doi:10.1101/2020.09.25.313312</dc:identifier>
<dc:title><![CDATA[A multiscale analysis of early flower development in Arabidopsis provides an integrated view of molecular regulation and growth control]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.26.314773v1?rss=1">
<title>
<![CDATA[
Genotypic similarity among algal symbionts corresponds to associations with closely related coral hosts 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.26.314773v1?rss=1</link>
<description><![CDATA[
Mutualisms where hosts are coupled metabolically to their symbionts often exhibit high partner fidelity. Most reef-building corals form obligate symbioses with specific species of photosymbionts, dinoflagellates in the family Symbiodiniaceae, despite needing to acquire symbionts early in their development from environmental sources. Three Caribbean acroporids (Acropora palmata, A. cervicornis, and their hybrid A. prolifera) are geographically sympatric across much of their range in the greater Caribbean, but often occupy different depth and light habitats. Both species and their hybrid associate with Symbiodinium  fitti, a genetically diverse species of symbiont that is specific to these hosts. Since the physiology of the dinoflagellate partner is strongly influenced by light (and therefore depth), we investigated whether S.  fitti populations from each host source were differentiated genetically. We generated shallow genome sequences of acroporid colonies sampled from across the Caribbean. Single Nucleotide Polymorphisms (SNPs) among S.  fitti strains were identified by aligning sequences to a ~600 Mb draft assembly of the S.  fitti genome, assembled from an A. cervicornis metagenome. Phylogenomic and multivariate analyses revealed that allelic variation among S.  fitti partitioned to each host species, as well as their hybrid, rather than by biogeographic origin. This is particularly noteworthy because the hybrid, A. prolifera, has a sparse fossil record and may be of relatively recent origin. Many of the SNPs putatively under selection were non-synonymous mutations predicted to alter protein efficiency. Differences in allele frequency among S.  fitti populations from each host taxon may correspond to distinct phenotypes that thrive in the different cellular environments found in each acroporid. The non-random sorting among genetically diverse strains, or genotypes, to different hosts could be the basis for lineage diversification via disruptive selection, leading to ecological specialization and ultimately speciation.
]]></description>
<dc:creator>Reich, H. G.</dc:creator>
<dc:creator>Kitchen, S. A.</dc:creator>
<dc:creator>Stankiewicz, K. H.</dc:creator>
<dc:creator>Devlin-Durante, M.</dc:creator>
<dc:creator>Fogarty, N. D.</dc:creator>
<dc:creator>Baums, I. B.</dc:creator>
<dc:date>2020-09-26</dc:date>
<dc:identifier>doi:10.1101/2020.09.26.314773</dc:identifier>
<dc:title><![CDATA[Genotypic similarity among algal symbionts corresponds to associations with closely related coral hosts]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.27.315283v1?rss=1">
<title>
<![CDATA[
Residue-by-residue analysis of cotranslational membrane protein integration in vivo 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.27.315283v1?rss=1</link>
<description><![CDATA[
We follow the cotranslational biosynthesis of three multi-spanning E. coli inner membrane proteins in vivo using high-resolution Force Profile Analysis. The force profiles show that the nascent chain is subjected to rapidly varying pulling forces during translation, and reveal unexpected complexities in the membrane integration process. We find that an N-terminal cytoplasmic domains can fold in the ribosome exit tunnel before membrane integration starts, that charged residues and membrane-interacting segments such as re-entrant loops and surface helices flanking a transmembrane helix (TMH) can advance or delay membrane integration, and that point mutations in an upstream TMH can affect the pulling forces generated by downstream TMHs in a highly position-dependent manner, suggestive of residue-specific interactions between TMHs during the integration process.
]]></description>
<dc:creator>Nicolaus, F.</dc:creator>
<dc:creator>Metola, A.</dc:creator>
<dc:creator>Mermans, D.</dc:creator>
<dc:creator>Liljenstrom, A.</dc:creator>
<dc:creator>Krc, A.</dc:creator>
<dc:creator>Abdullahi, S. M.</dc:creator>
<dc:creator>Zimmer, M.</dc:creator>
<dc:creator>Miller, T. F.</dc:creator>
<dc:creator>Von Heijne, G.</dc:creator>
<dc:date>2020-09-28</dc:date>
<dc:identifier>doi:10.1101/2020.09.27.315283</dc:identifier>
<dc:title><![CDATA[Residue-by-residue analysis of cotranslational membrane protein integration in vivo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.27.315556v1?rss=1">
<title>
<![CDATA[
Signal separability in integrated neurophotonics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.27.315556v1?rss=1</link>
<description><![CDATA[
A new modality Photonic probes record fluorescent signals by using arrays of light emitters and detectors embedded in neural tissue. Neither the emitted nor collected light fields are focused. Instead, in proposed configurations, hundreds of emitters will form rapid sequences of structured illumination patterns--providing sufficient spatial and temporal differentiation of neural signals for computational demixing. Here we define criteria for evaluating probe designs for achieving better signal separability. We find that probe geometry has profound, often unintuitive, effects on the separability of neural signals, providing initial design guidelines to achieve separation of individual cells in densely labeled populations.
]]></description>
<dc:creator>Yatsenko, D.</dc:creator>
<dc:creator>Moreaux, L. C.</dc:creator>
<dc:creator>Choi, J.</dc:creator>
<dc:creator>Tolias, A.</dc:creator>
<dc:creator>Shepard, K. L.</dc:creator>
<dc:creator>Roukes, M. L.</dc:creator>
<dc:date>2020-09-29</dc:date>
<dc:identifier>doi:10.1101/2020.09.27.315556</dc:identifier>
<dc:title><![CDATA[Signal separability in integrated neurophotonics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.30.317214v1?rss=1">
<title>
<![CDATA[
Implantable photonic neural probes for light-sheet fluorescence brain imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.30.317214v1?rss=1</link>
<description><![CDATA[
SignificanceLight-sheet fluorescence microscopy is a powerful technique for high-speed volumetric functional imaging. However, in typical light-sheet microscopes, the illumination and collection optics impose significant constraints upon the imaging of non-transparent brain tissues. Here, we demonstrate that these constraints can be surmounted using a new class of implantable photonic neural probes.

AimMass manufacturable, silicon-based light-sheet photonic neural probes can generate planar patterned illumination at arbitrary depths in brain tissues without any additional micro-optic components.

ApproachWe develop implantable photonic neural probes that generate light sheets in tissue. The probes were fabricated in a photonics foundry on 200 mm diameter silicon wafers. The light sheets were characterized in fluorescein and in free space. The probe-enabled imaging approach was tested in fixed and in vitro mouse brain tissues. Imaging tests were also performed using fluorescent beads suspended in agarose.

ResultsThe probes had 5 to 10 addressable sheets and average sheet thicknesses < 16 m for propagation distances up to 300 m in free space. Imaging areas were as large as {approx} 240 m x 490 m in brain tissue. Image contrast was enhanced relative to epifluorescence microscopy.

ConclusionsThe neural probes can lead to new variants of light-sheet fluorescence microscopy for deep brain imaging and experiments in freely-moving animals.
]]></description>
<dc:creator>Sacher, W. D.</dc:creator>
<dc:creator>Chen, F.-D.</dc:creator>
<dc:creator>Moradi-Chameh, H.</dc:creator>
<dc:creator>Luo, X.</dc:creator>
<dc:creator>Fomenko, A.</dc:creator>
<dc:creator>Shah, P.</dc:creator>
<dc:creator>Lordello, T.</dc:creator>
<dc:creator>Liu, X.</dc:creator>
<dc:creator>Felts Almog, I.</dc:creator>
<dc:creator>Straguzzi, J. N.</dc:creator>
<dc:creator>Fowler, T. M.</dc:creator>
<dc:creator>Jung, Y.</dc:creator>
<dc:creator>Hu, T.</dc:creator>
<dc:creator>Jeong, J.</dc:creator>
<dc:creator>Lozano, A. M.</dc:creator>
<dc:creator>Guo-Qiang Lo, P.</dc:creator>
<dc:creator>Valiante, T. A.</dc:creator>
<dc:creator>Moreaux, L. C.</dc:creator>
<dc:creator>Poon, J. K. S.</dc:creator>
<dc:creator>Roukes, M. L.</dc:creator>
<dc:date>2020-09-30</dc:date>
<dc:identifier>doi:10.1101/2020.09.30.317214</dc:identifier>
<dc:title><![CDATA[Implantable photonic neural probes for light-sheet fluorescence brain imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.02.323477v1?rss=1">
<title>
<![CDATA[
Neurogenetic and genomic approaches reveal roles for Dpr/DIP cell adhesion molecules in Drosophila reproductive behavior 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.02.323477v1?rss=1</link>
<description><![CDATA[
Drosophila reproductive behaviors are directed by fruitless neurons (fru P1 isoforms). A reanalysis of genomic studies shows that genes encoding dpr and DIP Immunoglobulin superfamily (IgSF) members are expressed in fru P1 neurons. Each fru P1and dpr/DIP (fru P1 {cap} dpr/DIP) overlapping expression pattern is similar in both sexes, with dimorphism in neuronal morphology and cell number. Behavioral studies of fru P1 {cap} dpr/DIP perturbation genotypes point to the mushroom body functioning together with the lateral protocerebral complex. Functionally, we find that perturbations of sex hierarchy genes and DIP-{varepsilon} changes sex-specific morphology of fru P1 {cap} DIP- neurons. A single-cell RNA-seq analysis shows that the DIPs have high expression in a restricted set of fru P1 neurons, whereas the dprs are expressed in larger set of neurons at intermediate levels, with a myriad of combinations.
]]></description>
<dc:creator>Arbeitman, M.</dc:creator>
<dc:creator>Brovero, S. G.</dc:creator>
<dc:creator>Fortier, J. C.</dc:creator>
<dc:creator>Hu, H.</dc:creator>
<dc:creator>Lovejoy, P. C.</dc:creator>
<dc:creator>Newell, N. R.</dc:creator>
<dc:creator>Palmateer, C.</dc:creator>
<dc:creator>Tzeng, R.-Y.</dc:creator>
<dc:creator>Lee, P.-T.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:date>2020-10-04</dc:date>
<dc:identifier>doi:10.1101/2020.10.02.323477</dc:identifier>
<dc:title><![CDATA[Neurogenetic and genomic approaches reveal roles for Dpr/DIP cell adhesion molecules in Drosophila reproductive behavior]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.14.338715v1?rss=1">
<title>
<![CDATA[
RNA-binding protein Elavl1/HuR is required for maintenance of cranial neural crest specification 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.14.338715v1?rss=1</link>
<description><![CDATA[
While neural crest development is known to be transcriptionally controlled via sequential activation of gene regulatory networks (GRNs), recent evidence increasingly implicates a role for post-transcriptional regulation in modulating the output of these regulatory circuits. Using available single cell RNA-sequencing datasets from avian embryos to identify potential post-transcriptional regulators, we found that Elavl1, which encodes for an RNA-binding protein with roles in transcript stability, was enriched in the premigratory cranial neural crest. Perturbation of Elavl1 resulted in premature neural crest delamination from the neural tube as well as significant reduction in transcripts associated with the neural crest specification GRN, phenotypes that are also observed with downregulation of the canonical Wnt inhibitor Draxin. That Draxin is the primary target for stabilization by Elavl1 during cranial neural crest specification was shown by RNA-sequencing, RNA-immunoprecipitation, RNA decay measurement and proximity ligation assays, further supporting the idea that the downregulation of neural crest specifier expression upon Elavl1 knockdown was largely due to loss of Draxin. Importantly, exogenous Draxin rescued cranial neural crest specification defects observed with Elavl1 knockdown. Thus, Elavl1 plays a critical a role in the maintenance of cranial neural crest specification via Draxin mRNA stabilization. Together, these data highlight an important intersection of post-transcriptional regulation with modulation of the neural crest specification GRN.
]]></description>
<dc:creator>Hutchins, E. J.</dc:creator>
<dc:creator>Chacon, J.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:date>2020-10-14</dc:date>
<dc:identifier>doi:10.1101/2020.10.14.338715</dc:identifier>
<dc:title><![CDATA[RNA-binding protein Elavl1/HuR is required for maintenance of cranial neural crest specification]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.16.342899v1?rss=1">
<title>
<![CDATA[
Force transduction creates long-ranged coupling in ribosomes stalled by arrest peptides 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.16.342899v1?rss=1</link>
<description><![CDATA[
Force-sensitive arrest peptides regulate protein biosynthesis by stalling the ribosome as they are translated. Synthesis can be resumed when the nascent arrest peptide experiences a pulling force of sufficient magnitude to break the stall. Efficient stalling is dependent on the specific identity of a large number of amino acids, including amino acids which are tens of angstroms away from the peptidyl transferase center (PTC). The mechanism of force-induced restart and the role of these essential amino acids far from the PTC is currently unknown. We use hundreds of independent molecular dynamics trajectories spanning over 120 s in combination with kinetic analysis to characterize the barriers along the force-induced restarting pathway for the arrest peptide SecM. We find that the essential amino acids far from the PTC play a major role in controlling the transduction of applied force. In successive states along the stall-breaking pathway, the applied force propagates up the nascent chain until it reaches the C-terminus of SecM and the PTC, inducing conformational changes that allow for restart of translation. A similar mechanism of force propagation through multiple states is observed in the VemP stall-breaking pathway, but secondary structure in VemP allows for heterogeneity in the order of transitions through intermediate states. Results from both arrest peptides explain how residues that are tens of angstroms away from the catalytic center of the ribosome impact stalling efficiency by mediating the response to an applied force and shielding the amino acids responsible for maintaining the stalled state of the PTC.

Significance StatementAs nascent proteins are synthesized by the ribosome, their interactions with the environment can create pulling forces on the nascent protein that can be transmitted to the ribosomes catalytic center. These forces can affect the rate and even the outcome of translation. We use simulations to characterize the pathway of force transduction along arrest peptides and discover how secondary structure in the nascent protein and its interactions with the ribosome exit tunnel impede force propagation. This explains how amino acids in arrest peptides that are tens of angstroms away from the ribosomes catalytic center contribute to stalling, and, more broadly, suggests how structural features in the nascent protein dictate the ribosomes ability to functionally respond to its environment.
]]></description>
<dc:creator>Zimmer, M. H.</dc:creator>
<dc:creator>Niesen, M. J.</dc:creator>
<dc:creator>Miller, T. F.</dc:creator>
<dc:date>2020-10-16</dc:date>
<dc:identifier>doi:10.1101/2020.10.16.342899</dc:identifier>
<dc:title><![CDATA[Force transduction creates long-ranged coupling in ribosomes stalled by arrest peptides]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.18.344382v1?rss=1">
<title>
<![CDATA[
Fundamental limits on the rate of bacterial growth 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.18.344382v1?rss=1</link>
<description><![CDATA[
Recent years have seen an experimental deluge interrogating the relationship between bacterial growth rate, cell size, and protein content, quantifying the abundance of proteins across growth conditions with unprecedented resolution. However, we still lack a rigorous understanding of what sets the scale of these quantities and when protein abundances should (or should not) depend on growth rate. Here, we seek to quantitatively understand this relationship across a collection of Escherichia coli proteomic data covering {approx} 4000 proteins and 36 growth rates. We estimate the basic requirements for steady-state growth by considering key processes in nutrient transport, cell envelope biogenesis, energy generation, and the central dogma. From these estimates, ribosome biogenesis emerges as a primary determinant of growth rate. We expand on this assessment by exploring a model of proteomic regulation as a function of the nutrient supply, revealing a mechanism that ties cell size and growth rate to ribosomal content.
]]></description>
<dc:creator>Belliveau, N. M.</dc:creator>
<dc:creator>Chure, G. D.</dc:creator>
<dc:creator>Hueschen, C. L.</dc:creator>
<dc:creator>Garcia, H. G.</dc:creator>
<dc:creator>Kondev, J.</dc:creator>
<dc:creator>Fisher, D. S.</dc:creator>
<dc:creator>Theriot, J. A.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2020-10-18</dc:date>
<dc:identifier>doi:10.1101/2020.10.18.344382</dc:identifier>
<dc:title><![CDATA[Fundamental limits on the rate of bacterial growth]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.18.344523v1?rss=1">
<title>
<![CDATA[
Temporal changes in plasma membrane lipid content induce endocytosis to regulate developmental epithelial-to-mesenchymal transition 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.18.344523v1?rss=1</link>
<description><![CDATA[
Epithelial-to-mesenchymal transition (EMT) is a dramatic change in cellular physiology during development and metastasis which involves coordination between cell signaling, adhesion, and membrane protrusions. These processes all involve dynamic changes in the plasma membrane, yet how membrane lipid content regulates membrane function during developmental EMT remains incompletely understood. By screening for differential expression of lipid-modifying genes over the course of EMT in avian neural crest, we have identified the ceramide-producing enzyme neutral sphingomyelinase 2 (nSMase2) as a critical regulator of a developmental EMT. nSMase2 expression begins at the onset of EMT, and in vivo knockdown experiments demonstrate that nSMase2 is necessary for neural crest migration. Further, we find that nSMase2 promotes Wnt and BMP signaling, and is required to activate the mesenchymal gene expression program. Mechanistically, we show that nSMase2 is sufficient to induce endocytosis, and that inhibition of endocytosis mimics nSMase2 knockdown. Our results support a model in which nSMase2 is expressed at the onset of neural crest EMT to produce ceramide and induce membrane curvature, thus increasing endocytosis of Wnt and BMP signaling complexes and activating pro-migratory gene expression. These results highlight the critical role of plasma membrane lipid metabolism in regulating transcriptional changes during developmental EMT programs.
]]></description>
<dc:creator>Piacentino, M. L.</dc:creator>
<dc:creator>Hutchins, E. J.</dc:creator>
<dc:creator>Andrews, C. J.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:date>2020-10-18</dc:date>
<dc:identifier>doi:10.1101/2020.10.18.344523</dc:identifier>
<dc:title><![CDATA[Temporal changes in plasma membrane lipid content induce endocytosis to regulate developmental epithelial-to-mesenchymal transition]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.19.343129v1?rss=1">
<title>
<![CDATA[
A multimodal cell census and atlas of the mammalian primary motor cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.19.343129v1?rss=1</link>
<description><![CDATA[
We report the generation of a multimodal cell census and atlas of the mammalian primary motor cortex (MOp or M1) as the initial product of the BRAIN Initiative Cell Census Network (BICCN). This was achieved by coordinated large-scale analyses of single-cell transcriptomes, chromatin accessibility, DNA methylomes, spatially resolved single-cell transcriptomes, morphological and electrophysiological properties, and cellular resolution input-output mapping, integrated through cross-modal computational analysis. Together, our results advance the collective knowledge and understanding of brain cell type organization: First, our study reveals a unified molecular genetic landscape of cortical cell types that congruently integrates their transcriptome, open chromatin and DNA methylation maps. Second, cross-species analysis achieves a unified taxonomy of transcriptomic types and their hierarchical organization that are conserved from mouse to marmoset and human. Third, cross-modal analysis provides compelling evidence for the epigenomic, transcriptomic, and gene regulatory basis of neuronal phenotypes such as their physiological and anatomical properties, demonstrating the biological validity and genomic underpinning of neuron types and subtypes. Fourth, in situ single-cell transcriptomics provides a spatially-resolved cell type atlas of the motor cortex. Fifth, integrated transcriptomic, epigenomic and anatomical analyses reveal the correspondence between neural circuits and transcriptomic cell types. We further present an extensive genetic toolset for targeting and fate mapping glutamatergic projection neuron types toward linking their developmental trajectory to their circuit function. Together, our results establish a unified and mechanistic framework of neuronal cell type organization that integrates multi-layered molecular genetic and spatial information with multi-faceted phenotypic properties.
]]></description>
<dc:creator>BRAIN Initiative Cell Census Network (BICCN),</dc:creator>
<dc:creator>Adkins, R. S.</dc:creator>
<dc:creator>Aldridge, A. I.</dc:creator>
<dc:creator>Allen, S.</dc:creator>
<dc:creator>Ament, S. A.</dc:creator>
<dc:creator>An, X.</dc:creator>
<dc:creator>Armand, E.</dc:creator>
<dc:creator>Ascoli, G. A.</dc:creator>
<dc:creator>Bakken, T. E.</dc:creator>
<dc:creator>Bandrowski, A.</dc:creator>
<dc:creator>Banerjee, S.</dc:creator>
<dc:creator>Barkas, N.</dc:creator>
<dc:creator>Bartlett, A.</dc:creator>
<dc:creator>Bateup, H. S.</dc:creator>
<dc:creator>Behrens, M. M.</dc:creator>
<dc:creator>Berens, P.</dc:creator>
<dc:creator>Berg, J.</dc:creator>
<dc:creator>Bernabucci, M.</dc:creator>
<dc:creator>Bernaerts, Y.</dc:creator>
<dc:creator>Bertagnolli, D.</dc:creator>
<dc:creator>Biancalani, T.</dc:creator>
<dc:creator>Boggeman, L.</dc:creator>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Bowman, I.</dc:creator>
<dc:creator>Bravo, H. C.</dc:creator>
<dc:creator>Cadwell, C. R.</dc:creator>
<dc:creator>Callaway, E. M.</dc:creator>
<dc:creator>Carlin, B.</dc:creator>
<dc:creator>O'Connor, C.</dc:creator>
<dc:creator>Carter, R.</dc:creator>
<dc:creator>Casper, T.</dc:creator>
<dc:creator>Castanon, R. G.</dc:creator>
<dc:creator>Castro, J. R.</dc:creator>
<dc:creator>Chance, R. K.</dc:creator>
<dc:creator>Chatterjee, A.</dc:creator>
<dc:creator>Chen, H.</dc:creator>
<dc:creator>Chun, J.</dc:creator>
<dc:creator>Colantuoni, C.</dc:creator>
<dc:creator>Crabtree, J.</dc:creator>
<dc:creator>Creasy, H.</dc:creator>
<dc:creator>Cric</dc:creator>
<dc:date>2020-10-21</dc:date>
<dc:identifier>doi:10.1101/2020.10.19.343129</dc:identifier>
<dc:title><![CDATA[A multimodal cell census and atlas of the mammalian primary motor cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.19.344838v1?rss=1">
<title>
<![CDATA[
The Brain Knows enough to take into account Light and Shadow 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.19.344838v1?rss=1</link>
<description><![CDATA[
Visual perception requires to infer object and light source color to maintain constancy. This study demonstrates the influences of environmental sunlight color trajectory (blue-white-yellow-red), and associated color of scattered light in shadows on color perception. In Adelsons checkerboard shadow illusion, squares of equal luminance appear lighter or darker depending on whether they are inside or outside a cast shadow1. In some color variations, illusion magnitude is attenuated by specific colors of the cast shadow. Particularly in the green monotone environment (green checkerboard under green ambient and diffusion light), illusion magnitude reduces down nearly to zero. In contrast, shading by structure is not affected by the color environment. Thus, the cast shadow and shading by structure have distinct effects on surface color constancy. This illusion attenuation may be related to the absence of green in the natural environmental light spectrum, including in cast shadows. The brain may utilize the implicit learned trajectory of natural light to resolve ambiguity in surface reflectance. Our results provide a new formula not only to understand, but also to generate new variations of other illusions such as #The Dress.
]]></description>
<dc:creator>Yamamoto, M.</dc:creator>
<dc:creator>Shimojo, S.</dc:creator>
<dc:date>2020-10-19</dc:date>
<dc:identifier>doi:10.1101/2020.10.19.344838</dc:identifier>
<dc:title><![CDATA[The Brain Knows enough to take into account Light and Shadow]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.19.345538v1?rss=1">
<title>
<![CDATA[
Juvenile corals inherit mutations acquired during the parents lifespan 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.19.345538v1?rss=1</link>
<description><![CDATA[
128 years ago, August Weismann proposed that the only source of inherited genetic variation in animals is the germline1. Julian Huxley reasoned that if this were true, it would falsify Jean-Baptiste Lamarcks theory that acquired characteristics are heritable2. Since then, scientists have discovered that not all animals segregate germline cells from somatic cells permanently and early in development3. In fact, throughout their lives, Cnidaria4-6 and Porifera7 maintain primordial stem cells that continuously give rise to both germline and somatic cells. The fate of mutations generated in this primordial stem cell line during adulthood remains an open question. It was unknown whether post-embryonic mutations could be heritable in animals8-10--until now. Here we use two independent genetic marker analyses to show that post-embryonic mutations are inherited in the coral Acropora palmata (Cnidaria, Anthozoa). This discovery upends the long-held supposition that post-embryonic genetic mutations acquired over an animals lifetime in non-germline tissues are not heritable2. Over the centuries-long lifespan of a coral, the inheritance of post-embryonic mutations may not only change allele frequencies in the local larval pool but may also spread novel alleles across great distances via larval dispersal. Thus, corals may have the potential to adapt to changing environments via heritable somatic mutations10. This mechanism challenges our understanding of animal adaptation and prompts a deeper examination of both the process of germline determination in Cnidaria and the role of post-embryonic genetic mutations in adaptation and epigenetics of modular animals. Understanding the role of post-embryonic mutations in animal adaptation will be crucial as ecological change accelerates in the Anthropocene.
]]></description>
<dc:creator>Vasquez-Kuntz, K. L.</dc:creator>
<dc:creator>Kitchen, S. A.</dc:creator>
<dc:creator>Conn, T. L.</dc:creator>
<dc:creator>Vohsen, S. A.</dc:creator>
<dc:creator>Chan, A. N.</dc:creator>
<dc:creator>Vermeij, M. J.</dc:creator>
<dc:creator>Page, C.</dc:creator>
<dc:creator>Marhaver, K. L.</dc:creator>
<dc:creator>Baums, I. B.</dc:creator>
<dc:date>2020-10-20</dc:date>
<dc:identifier>doi:10.1101/2020.10.19.345538</dc:identifier>
<dc:title><![CDATA[Juvenile corals inherit mutations acquired during the parents lifespan]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.20.347427v1?rss=1">
<title>
<![CDATA[
In vivo  imaging of retrovirus infection reveals a role for Siglec-1/CD169 in multiple routes of transmission 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.20.347427v1?rss=1</link>
<description><![CDATA[
Early events in retrovirus transmission are determined by interactions between incoming viruses and frontline cells near entry sites. Despite their importance for retroviral pathogenesis, very little is known about these events. We developed a bioluminescence imaging (BLI)-guided multiscale imaging approach to study these events in vivo. Engineered murine leukemia reporter viruses allowed us to monitor individual stages of the retrovirus life cycle including virus particle flow, virus entry into cells, infection and spread for retroorbital, subcutaneous and oral routes. BLI permitted temporal tracking of orally administered retroviruses along the gastrointestinal tract as they traversed the lumen through Peyers Patch to reach the draining mesenteric sac. Importantly, capture and acquisition of lymph-, blood- and milk-borne retroviruses spanning three routes, was promoted by a common host factor, the I-type lectin CD169, expressed on sentinel macrophages. These results highlight how retroviruses co-opt the immune surveillance function of tissue resident sentinel macrophages for establishing infection.
]]></description>
<dc:creator>Haugh, K. A.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Ullah, I.</dc:creator>
<dc:creator>Pi, R.</dc:creator>
<dc:creator>Gilardet, A.</dc:creator>
<dc:creator>Kumar, P.</dc:creator>
<dc:creator>Bjorkman, P.</dc:creator>
<dc:creator>Mothes, W.</dc:creator>
<dc:creator>Uchil, P. D.</dc:creator>
<dc:date>2020-10-20</dc:date>
<dc:identifier>doi:10.1101/2020.10.20.347427</dc:identifier>
<dc:title><![CDATA[In vivo  imaging of retrovirus infection reveals a role for Siglec-1/CD169 in multiple routes of transmission]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.03.367391v1?rss=1">
<title>
<![CDATA[
Evolution of Antibody Immunity to SARS-CoV-2 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.03.367391v1?rss=1</link>
<description><![CDATA[
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has infected 78 million individuals and is responsible for over 1.7 million deaths to date. Infection is associated with development of variable levels of antibodies with neutralizing activity that can protect against infection in animal models. Antibody levels decrease with time, but the nature and quality of the memory B cells that would be called upon to produce antibodies upon re-infection has not been examined. Here we report on the humoral memory response in a cohort of 87 individuals assessed at 1.3 and 6.2 months after infection. We find that IgM, and IgG anti-SARS-CoV-2 spike protein receptor binding domain (RBD) antibody titers decrease significantly with IgA being less affected. Concurrently, neutralizing activity in plasma decreases by five-fold in pseudotype virus assays. In contrast, the number of RBD-specific memory B cells is unchanged. Memory B cells display clonal turnover after 6.2 months, and the antibodies they express have greater somatic hypermutation, increased potency and resistance to RBD mutations, indicative of continued evolution of the humoral response. Analysis of intestinal biopsies obtained from asymptomatic individuals 4 months after coronavirus disease-2019 (COVID-19) onset, using immunofluorescence, or polymerase chain reaction, revealed persistence of SARS-CoV-2 nucleic acids and immunoreactivity in the small bowel of 7 out of 14 volunteers. We conclude that the memory B cell response to SARS-CoV-2 evolves between 1.3 and 6.2 months after infection in a manner that is consistent with antigen persistence.
]]></description>
<dc:creator>Gaebler, C.</dc:creator>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>Lorenzi, J. C. C.</dc:creator>
<dc:creator>Muecksch, F.</dc:creator>
<dc:creator>Finkin, S.</dc:creator>
<dc:creator>Tokuyama, M.</dc:creator>
<dc:creator>Ladinsky, M.</dc:creator>
<dc:creator>Cho, A.</dc:creator>
<dc:creator>Jankovic, M.</dc:creator>
<dc:creator>Schaefer-Babajew, D.</dc:creator>
<dc:creator>Oliveira, T. Y.</dc:creator>
<dc:creator>Cipolla, M.</dc:creator>
<dc:creator>Viant, C.</dc:creator>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Hurley, A.</dc:creator>
<dc:creator>Turroja, M.</dc:creator>
<dc:creator>Gordon, K.</dc:creator>
<dc:creator>Millard, K. G.</dc:creator>
<dc:creator>Ramos, V.</dc:creator>
<dc:creator>Schmidt, F.</dc:creator>
<dc:creator>Weisblum, Y.</dc:creator>
<dc:creator>Jha, D.</dc:creator>
<dc:creator>Tankelevich, M.</dc:creator>
<dc:creator>Yee, J.</dc:creator>
<dc:creator>Shimeliovich, I.</dc:creator>
<dc:creator>Robbiani, D. F.</dc:creator>
<dc:creator>Zhao, Z.</dc:creator>
<dc:creator>Gazumyan, A.</dc:creator>
<dc:creator>Hatziioannou, T.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Mehandru, S.</dc:creator>
<dc:creator>Bieniasz, P. D.</dc:creator>
<dc:creator>Caskey, M.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:date>2020-11-05</dc:date>
<dc:identifier>doi:10.1101/2020.11.03.367391</dc:identifier>
<dc:title><![CDATA[Evolution of Antibody Immunity to SARS-CoV-2]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.03.367540v1?rss=1">
<title>
<![CDATA[
Sticks and Stones, a conserved cell surface ligand for the Type IIa RPTP Lar, regulates neural circuit wiring in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.03.367540v1?rss=1</link>
<description><![CDATA[
Control of tyrosine phosphorylation is an essential element of many cellular processes, including proliferation, differentiation neurite outgrowth, and synaptogenesis. Receptor-like protein-tyrosine phosphatases (RPTPs) have cytoplasmic phosphatase domains and cell adhesion molecule (CAM)-like extracellular domains that interact with cell-surface ligands and/or co-receptors. We identified a new ligand for the Drosophila Lar RPTP, the immunoglobulin superfamily CAM Sticks and Stones (Sns). Lar is orthologous to the three Type IIa mammalian RPTPs, PTPRF (LAR), PTPRD (PTP{delta}), and PTPRS (PTP{sigma}). Lar and Sns bind to each other in embryos and in vitro. The human Sns ortholog, Nephrin, binds to PTPRD and PTPRF. Genetic interaction studies show that Sns is essential to Lars functions in several developmental contexts in the larval and adult nervous systems. In the larval neuromuscular system, Lar and sns transheterozygotes (Lar/sns transhets) have synaptic defects like those seen in Lar mutants and Sns knockdown animals. Lar and Sns reporters are both expressed in motor neurons and not in muscles, so Lar and Sns likely act in cis (in the same neurons). Lar mutants and Lar/sns transhets have identical axon guidance defects in the larval mushroom body in which Kenyon cell axons fail to stop at the midline and do not branch. Pupal Kenyon cell axon guidance is similarly affected, resulting in adult mushroom body defects. Lar is expressed in larval and pupal Kenyon cells, but Sns is not, so Lar-Sns interactions in this system must be in trans (between neurons). Lastly, R7 photoreceptor axons in Lar mutants and Lar/sns transhets fail to innervate the correct M6 layer of the medulla in the optic lobe. Lar acts cell-autonomously in R7s, while Sns is only in lamina and medulla neurons that arborize near the R7 target layer. Therefore, the Lar-Sns interactions that control R7 targeting also occur in trans.
]]></description>
<dc:creator>Bali, N.</dc:creator>
<dc:creator>Lee, H.-K.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:date>2020-11-05</dc:date>
<dc:identifier>doi:10.1101/2020.11.03.367540</dc:identifier>
<dc:title><![CDATA[Sticks and Stones, a conserved cell surface ligand for the Type IIa RPTP Lar, regulates neural circuit wiring in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.04.368381v1?rss=1">
<title>
<![CDATA[
Stability and Control of Biomolecular Circuits through Structure 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.04.368381v1?rss=1</link>
<description><![CDATA[
Due to omnipresent uncertainties and environmental disturbances, natural and engineered biological organisms face the challenging control problem of achieving robust performance using unreliable parts. The key to overcoming this challenge rests in identifying structures of biomolecular circuits that are largely invariant despite uncertainties, and building feedback control through such structures. In this work, we develop the tool of log derivatives to capture structures in how the production and degradation rates of molecules depend on concentrations of reactants. We show that log derivatives could establish stability of fixed points based on structure, despite large variations in rates and functional forms of models. Furthermore, we demonstrate how control objectives, such as robust perfect adaptation (i.e. step disturbance rejection), could be implemented through the structures captured. Due to the methods simplicity, structural properties for analysis and design of biomolecular circuits can often be determined by a glance at the equations.
]]></description>
<dc:creator>Xiao, F.</dc:creator>
<dc:creator>Doyle, J. C.</dc:creator>
<dc:creator>Khammash, M.</dc:creator>
<dc:date>2020-11-05</dc:date>
<dc:identifier>doi:10.1101/2020.11.04.368381</dc:identifier>
<dc:title><![CDATA[Stability and Control of Biomolecular Circuits through Structure]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.10.377051v1?rss=1">
<title>
<![CDATA[
Bistable State Switch Enables Ultrasensitive Feedback Control in Heterogeneous Microbial Populations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.10.377051v1?rss=1</link>
<description><![CDATA[
Molecular feedback control circuits can improve robustness of gene expression at the single cell-level. This achievement can be offset by requirements of rapid protein expression, that may induce cellular stress, known as burden, that reduces colony growth. To begin to address this challenge we take inspiration by  division-of-labor in heterogeneous cell populations: we propose to combine bistable switches and quorum sensing systems to coordinate gene expression at the population-level. We show that bistable switches in individual cells operating in parallel yield an ultrasensitive response, while cells maintain heterogeneous levels of gene expression to avoid burden across all cells. Within a feedback loop, these switches can achieve robust reference tracking and adaptation to disturbances at the population-level. We also demonstrate that molecular sequestration enables tunable hysteresis in individual switches, making it possible to obtain a wide range of stable population-level expressions.
]]></description>
<dc:creator>Ren, X.</dc:creator>
<dc:creator>Samaniego, C. C.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:creator>Franco, E.</dc:creator>
<dc:date>2020-11-10</dc:date>
<dc:identifier>doi:10.1101/2020.11.10.377051</dc:identifier>
<dc:title><![CDATA[Bistable State Switch Enables Ultrasensitive Feedback Control in Heterogeneous Microbial Populations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.10.377085v1?rss=1">
<title>
<![CDATA[
Engineering Logical Inflammation Sensing Circuit for Modulating Gut Conditions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.10.377085v1?rss=1</link>
<description><![CDATA[
Bacteria genetically engineered to execute defined therapeutic and diagnostic functions in physiological settings can be applied to colonize the human microbiome, providing in situ surveillance and conditional disease modulation. However, many engineered microbes can only respond to single-input environmental factors, limiting their tunability, precision, and effectiveness as living diagnostic and therapeutic systems. For engineering microbes to improve complex chronic disorders such as inflammatory bowel disease, the bacteria must respond to combinations of stimuli in the proper context and time. This work implements a previously characterized split activator AND logic gate in the probiotic Escherichia coli strain Nissle 1917. Our system can respond to two input signals: the inflammatory biomarker tetrathionate and a second input signal, anhydrotetracycline (aTc), for manual control. We report 4-6 fold induction with a minimal leak when the two chemical signals are present. We model the AND gate dynamics using chemical reaction networks and tune parameters in silico to identify critical perturbations that affect our circuits selectivity. Finally, we engineer the optimized AND gate to secrete a therapeutic anti-inflammatory cytokine IL-22 using the hemolysin secretion pathway in the probiotic E. coli strain. We used a germ-free transwell model of the human gut epithelium to show that our engineering bacteria produce similar host cytokine responses compared to pure cytokine. Our study presents a scalable workflow to engineer cytokine-secreting microbes. It demonstrates the feasibility of IL-22 derived from probiotic E. coli Nissle with minimal off-target effects in a gut epithelial context.
]]></description>
<dc:creator>Merk, L. N.</dc:creator>
<dc:creator>Shur, A.</dc:creator>
<dc:creator>Pandey, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:creator>Green, L. N.</dc:creator>
<dc:date>2020-11-10</dc:date>
<dc:identifier>doi:10.1101/2020.11.10.377085</dc:identifier>
<dc:title><![CDATA[Engineering Logical Inflammation Sensing Circuit for Modulating Gut Conditions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.12.378422v1?rss=1">
<title>
<![CDATA[
Massive X-ray screening reveals two allosteric drug binding sites of SARS-CoV-2 main protease 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.12.378422v1?rss=1</link>
<description><![CDATA[
The coronavirus disease (COVID-19) caused by SARS-CoV-2 is creating tremendous health problems and economical challenges for mankind. To date, no effective drug is available to directly treat the disease and prevent virus spreading. In a search for a drug against COVID-19, we have performed a massive X-ray crystallographic screen of two repurposing drug libraries against the SARS-CoV-2 main protease (Mpro), which is essential for the virus replication and, thus, a potent drug target. In contrast to commonly applied X-ray fragment screening experiments with molecules of low complexity, our screen tested already approved drugs and drugs in clinical trials. From the three-dimensional protein structures, we identified 37 compounds binding to Mpro. In subsequent cell-based viral reduction assays, one peptidomimetic and five non-peptidic compounds showed antiviral activity at non-toxic concentrations. We identified two allosteric binding sites representing attractive targets for drug development against SARS-CoV-2.
]]></description>
<dc:creator>Guenther, S.</dc:creator>
<dc:creator>Reinke, P. Y. A.</dc:creator>
<dc:creator>Fernandez-Garcia, Y.</dc:creator>
<dc:creator>Lieske, J.</dc:creator>
<dc:creator>Lane, T. J.</dc:creator>
<dc:creator>Ginn, H.</dc:creator>
<dc:creator>Koua, F.</dc:creator>
<dc:creator>Ehrt, C.</dc:creator>
<dc:creator>Ewert, W.</dc:creator>
<dc:creator>Oberthuer, D.</dc:creator>
<dc:creator>Yefanov, O.</dc:creator>
<dc:creator>Meier, S.</dc:creator>
<dc:creator>Lorenzen, K.</dc:creator>
<dc:creator>Krichel, B.</dc:creator>
<dc:creator>Kopicki, J.</dc:creator>
<dc:creator>Gelisio, L.</dc:creator>
<dc:creator>Brehm, W.</dc:creator>
<dc:creator>Dunkel, I.</dc:creator>
<dc:creator>Seychell, B.</dc:creator>
<dc:creator>Gieseler, H.</dc:creator>
<dc:creator>Norton-Baker, B.</dc:creator>
<dc:creator>Escudero-Perez, B.</dc:creator>
<dc:creator>Domaracky, M.</dc:creator>
<dc:creator>Saouane, S.</dc:creator>
<dc:creator>Tolstikova, A.</dc:creator>
<dc:creator>White, T.</dc:creator>
<dc:creator>Haenle, A.</dc:creator>
<dc:creator>Groessler, M.</dc:creator>
<dc:creator>Fleckenstein, H.</dc:creator>
<dc:creator>Trost, F.</dc:creator>
<dc:creator>Galchenkova, M.</dc:creator>
<dc:creator>Gevorkov, Y.</dc:creator>
<dc:creator>Li, C.</dc:creator>
<dc:creator>Awel, S.</dc:creator>
<dc:creator>Peck, A.</dc:creator>
<dc:creator>Barthelmess, M.</dc:creator>
<dc:creator>Schluenzen, F.</dc:creator>
<dc:creator>Lourdu, X. P.</dc:creator>
<dc:creator>Werner, N.</dc:creator>
<dc:creator>Andaleeb, H.</dc:creator>
<dc:creator>Ullah, N.</dc:creator>
<dc:creator>Falke, S.</dc:creator>
<dc:creator>Srinivasan, V.</dc:creator>
<dc:creator>Franca, B.</dc:creator>
<dc:creator>Schwi</dc:creator>
<dc:date>2020-11-12</dc:date>
<dc:identifier>doi:10.1101/2020.11.12.378422</dc:identifier>
<dc:title><![CDATA[Massive X-ray screening reveals two allosteric drug binding sites of SARS-CoV-2 main protease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.17.384669v1?rss=1">
<title>
<![CDATA[
Inhibition of VCP preserves retinal structure and function in autosomal dominant retinal degeneration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.17.384669v1?rss=1</link>
<description><![CDATA[
Due to continuously high production rates of rhodopsin (RHO) and high metabolic activity, photoreceptor neurons are especially vulnerable to defects in proteostasis. A proline to histidine substitution at position 23 (P23H) leads to production of structurally misfolded RHO, causing the most common form of autosomal dominant Retinitis Pigmentosa (adRP) in North America. The AAA-ATPase valosin-containing protein (VCP) extracts misfolded proteins from the ER membrane for cytosolic degradation. Here, we provide the first evidence that inhibition of VCP activity rescues degenerating P23H rod cells and improves their functional properties in P23H transgenic rat and P23H knock-in mouse retinae, both in vitro and in vivo. This improvement correlates with the restoration of the physiological RHO localization to rod outer segments (OS) and properly-assembled OS disks. As a single intravitreal injection suffices to deliver a long-lasting benefit in vivo, we suggest VCP inhibition as a potential therapeutic strategy for adRP patients carrying mutations in the RHO gene.
]]></description>
<dc:creator>Arango-Gonzalez, B.</dc:creator>
<dc:creator>Sen, M.</dc:creator>
<dc:creator>Guarascio, R.</dc:creator>
<dc:creator>Ziaka, K.</dc:creator>
<dc:creator>del Amo, E. M.</dc:creator>
<dc:creator>Hau, K.</dc:creator>
<dc:creator>Poultney, H.</dc:creator>
<dc:creator>Asfahani, R.</dc:creator>
<dc:creator>Urtti, A.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Bolz, S.</dc:creator>
<dc:creator>Deshaies, R. J.</dc:creator>
<dc:creator>Haq, W.</dc:creator>
<dc:creator>Cheetham, M. E.</dc:creator>
<dc:creator>Ueffing, M.</dc:creator>
<dc:date>2020-11-19</dc:date>
<dc:identifier>doi:10.1101/2020.11.17.384669</dc:identifier>
<dc:title><![CDATA[Inhibition of VCP preserves retinal structure and function in autosomal dominant retinal degeneration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.17.387092v1?rss=1">
<title>
<![CDATA[
Mosaic RBD nanoparticles elicit neutralizing antibodies against SARS-CoV-2 and zoonotic coronaviruses 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.17.387092v1?rss=1</link>
<description><![CDATA[
Protection against SARS-CoV-2 and SARS-related emergent zoonotic coronaviruses is urgently needed. We made homotypic nanoparticles displaying the receptor-binding domain (RBD) of SARS-CoV-2 or co-displaying SARS-CoV-2 RBD along with RBDs from animal betacoronaviruses that represent threats to humans (mosaic nanoparticles; 4-8 distinct RBDs). Mice immunized with RBD-nanoparticles, but not soluble antigen, elicited cross-reactive binding and neutralization responses. Mosaic-RBD-nanoparticles elicited antibodies with superior cross-reactive recognition of heterologous RBDs compared to sera from immunizations with homotypic SARS-CoV-2-RBD-nanoparticles or COVID-19 convalescent human plasmas. Moreover, sera from mosaic-RBD-immunized mice neutralized heterologous pseudotyped coronaviruses equivalently or better after priming than sera from homotypic SARS-CoV-2-RBD-nanoparticle immunizations, demonstrating no immunogenicity loss against particular RBDs resulting from co-display. A single immunization with mosaic-RBD-nanoparticles provides a potential strategy to simultaneously protect against SARS-CoV-2 and emerging zoonotic coronaviruses.

One sentence summaryNanoparticle strategy for pan-sarbecovirus vaccine

125-character summary for online ToCImmunizing with nanoparticles displaying diverse coronavirus RBDs elicits cross-reactive and neutralizing antibody responses.
]]></description>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Cohen, A. A.</dc:creator>
<dc:creator>Gnanapragasam, P. N. P.</dc:creator>
<dc:creator>Lee, Y. E.</dc:creator>
<dc:creator>Ou, S.</dc:creator>
<dc:creator>Kakutani, L. M.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:date>2020-11-17</dc:date>
<dc:identifier>doi:10.1101/2020.11.17.387092</dc:identifier>
<dc:title><![CDATA[Mosaic RBD nanoparticles elicit neutralizing antibodies against SARS-CoV-2 and zoonotic coronaviruses]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.17.387860v1?rss=1">
<title>
<![CDATA[
cancerAlign: Stratifying tumors by unsupervised alignment across cancer types 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.17.387860v1?rss=1</link>
<description><![CDATA[
Tumor stratification, which aims at clustering tumors into biologically meaningful subtypes, is the key step towards personalized treatment. Large-scale profiled cancer genomics data enables us to develop computational methods for tumor stratification. However, most of the existing approaches only considered tumors from an individual cancer type during clustering, leading to the overlook of common patterns across cancer types and the vulnerability to the noise within that cancer type. To address these challenges, we proposed cancerAlign to map tumors of the target cancer type into latent spaces of other source cancer types. These tumors were then clustered in each latent space rather than the original space in order to exploit shared patterns across cancer types. Due to the lack of aligned tumor samples across cancer types, cancerAlign used adversarial learning to learn the mapping at the population level. It then used consensus clustering to integrate cluster labels from different source cancer types. We evaluated cancerAlign on 7,134 tumors spanning 24 cancer types from TCGA and observed substantial improvement on tumor stratification and cancer gene prioritization. We further revealed the transferability across cancer types, which reflected the similarity among them based on the somatic mutation profile. cancerAlign is an unsupervised approach that provides deeper insights into the heterogeneous and rapidly accumulating somatic mutation profile and can be also applied to other genome-scale molecular information.

Availabilityhttps://github.com/bowen-gao/cancerAlign
]]></description>
<dc:creator>Gao, B.</dc:creator>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>Ma, J.</dc:creator>
<dc:creator>Wang, S.</dc:creator>
<dc:date>2020-11-20</dc:date>
<dc:identifier>doi:10.1101/2020.11.17.387860</dc:identifier>
<dc:title><![CDATA[cancerAlign: Stratifying tumors by unsupervised alignment across cancer types]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.18.388736v1?rss=1">
<title>
<![CDATA[
A genetic screen identifies dreammist as a regulator of sleep 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.18.388736v1?rss=1</link>
<description><![CDATA[
Sleep is a nearly universal feature of animal behaviour, yet many of the molecular, genetic, and neuronal substrates that orchestrate sleep/wake transitions lie undiscovered. Employing a viral insertion sleep screen in larval zebrafish, we identified a novel gene, dreammist (dmist), whose loss results in behavioural hyperactivity and reduced sleep at night. The neuronally expressed dmist gene is conserved across vertebrates and encodes a small single-pass transmembrane protein that is structurally similar to the Na+,K+-ATPase regulator, FXYD1/Phospholemman. Disruption of either fxyd1 or atp1a3a, a Na+,K+-ATPase alpha-3 subunit associated with several heritable movement disorders in humans, led to decreased night-time sleep. Since atpa1a3a and dmist mutants have elevated intracellular Na+ levels and non-additive effects on sleep amount at night, we propose that Dmist-dependent enhancement of Na+ pump function modulates neuronal excitability to maintain normal sleep behaviour.

Significance statementSleep is an essential behavioral state, but the genes that regulate sleep and wake states are still being uncovered. A viral insertion screen in zebrafish identified a novel sleep mutant called dreammist, in which a small, highly-conserved transmembrane protein is disrupted. The discovery of dreammist highlights the importance of a class of small transmembrane-protein modulators of the sodium pump in setting appropriate sleep duration.
]]></description>
<dc:creator>Barlow, I. L.</dc:creator>
<dc:creator>Mackay, E.</dc:creator>
<dc:creator>Wheater, E.</dc:creator>
<dc:creator>Goel, A.</dc:creator>
<dc:creator>Lim, S.</dc:creator>
<dc:creator>Zimmerman, S.</dc:creator>
<dc:creator>Woods, I.</dc:creator>
<dc:creator>Prober, D. A.</dc:creator>
<dc:creator>Rihel, J.</dc:creator>
<dc:date>2020-11-18</dc:date>
<dc:identifier>doi:10.1101/2020.11.18.388736</dc:identifier>
<dc:title><![CDATA[A genetic screen identifies dreammist as a regulator of sleep]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.20.391896v1?rss=1">
<title>
<![CDATA[
Highly multiplexed spatially resolved gene expression profiling of mouse organogenesis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.20.391896v1?rss=1</link>
<description><![CDATA[
Transcriptional and epigenetic profiling of single-cells has advanced our knowledge of the molecular bases of gastrulation and early organogenesis. However, current approaches rely on dissociating cells from tissues, thereby losing the crucial spatial context that is necessary for understanding cell and tissue interactions during development. Here, we apply an image-based single-cell transcriptomics method, seqFISH, to simultaneously and precisely detect mRNA molecules for 387 selected target genes in 8-12 somite stage mouse embryo tissue sections. By integrating spatial context and highly multiplexed transcriptional measurements with two single-cell transcriptome atlases we accurately characterize cell types across the embryo and demonstrate how spatially-resolved expression of genes not profiled by seqFISH can be imputed. We use this high-resolution spatial map to characterize fundamental steps in the patterning of the midbrain-hindbrain boundary and the developing gut tube. Our spatial atlas uncovers axes of resolution that are not apparent from single-cell RNA sequencing data - for example, in the gut tube we observe early dorsal-ventral separation of esophageal and tracheal progenitor populations. In sum, by computationally integrating high-resolution spatially-resolved gene expression maps with single-cell genomics data, we provide a powerful new approach for studying how and when cell fate decisions are made during early mammalian development.
]]></description>
<dc:creator>Lohoff, T.</dc:creator>
<dc:creator>Ghazanfar, S.</dc:creator>
<dc:creator>Missarova, A.</dc:creator>
<dc:creator>Koulena, N.</dc:creator>
<dc:creator>Pierson, N.</dc:creator>
<dc:creator>Griffiths, J. A.</dc:creator>
<dc:creator>Bardot, E. S.</dc:creator>
<dc:creator>Eng, C.-H. L.</dc:creator>
<dc:creator>Tyser, R. C. V.</dc:creator>
<dc:creator>Argelaguet, R.</dc:creator>
<dc:creator>Guibentif, C.</dc:creator>
<dc:creator>Srinivas, S.</dc:creator>
<dc:creator>Briscoe, J.</dc:creator>
<dc:creator>Simons, B. D.</dc:creator>
<dc:creator>Hadjantonakis, A.-K.</dc:creator>
<dc:creator>Gottgens, B.</dc:creator>
<dc:creator>Reik, W.</dc:creator>
<dc:creator>Nichols, J.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:creator>Marioni, J. C.</dc:creator>
<dc:date>2020-11-21</dc:date>
<dc:identifier>doi:10.1101/2020.11.20.391896</dc:identifier>
<dc:title><![CDATA[Highly multiplexed spatially resolved gene expression profiling of mouse organogenesis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.21.392720v1?rss=1">
<title>
<![CDATA[
A conserved strategy for inducing appendage regeneration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.21.392720v1?rss=1</link>
<description><![CDATA[
Can limb regeneration be induced? Few have pursued this question, and an evolutionarily conserved strategy has yet to emerge. This study reports a strategy for inducing regenerative response in appendages, which works across three species that span the animal phylogeny. In Cnidaria, the frequency of appendage regeneration in the moon jellyfish Aurelia was increased by feeding with the amino acid L-leucine and the growth hormone insulin. In insects, the same strategy induced tibia regeneration in adult Drosophila. Finally, in mammals, L-leucine and sucrose administration induced digit regeneration in adult mice, including dramatically from mid-phalangeal amputation. The conserved effect of L-leucine and insulin/sugar suggests a key role for energetic parameters in regeneration induction. The simplicity by which nutrient supplementation can induce appendage regeneration provides a testable hypothesis across animals.
]]></description>
<dc:creator>Abrams, M. J.</dc:creator>
<dc:creator>Tan, F. H.</dc:creator>
<dc:creator>Basinger, T.</dc:creator>
<dc:creator>Heithe, M. L.</dc:creator>
<dc:creator>Li, Y.</dc:creator>
<dc:creator>Raffiee, M.</dc:creator>
<dc:creator>Leahy, P.</dc:creator>
<dc:creator>Dabiri, J. O.</dc:creator>
<dc:creator>Gold, D. A.</dc:creator>
<dc:creator>Goentoro, L. A.</dc:creator>
<dc:date>2020-11-22</dc:date>
<dc:identifier>doi:10.1101/2020.11.21.392720</dc:identifier>
<dc:title><![CDATA[A conserved strategy for inducing appendage regeneration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.22.393546v1?rss=1">
<title>
<![CDATA[
Xist-seeded nucleation sites form local concentration gradients of silencing proteins to inactivate the X-chromosome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.22.393546v1?rss=1</link>
<description><![CDATA[
The long non-coding RNA Xist exploits numerous effector proteins to progressively induce gene silencing across the X chromosome and form the inactive X (Xi)-compartment. The mechanism underlying formation of the chromosome-wide Xi-compartment is poorly understood. Here, we find that formation of the Xi-compartment is induced by [~]50 locally confined granules, where two Xist RNA molecules nucleate supra-molecular complexes (SMCs) of interacting proteins. Xist-SMCs are transient structures that concentrate rapidly recycling proteins in the X by increasing protein binding affinity. We find that gene silencing originates at Xist-SMCs and propagates across the entire chromosome over time, achieved by Polycomb-mediated coalescence of chromatin regions and aggregation, via its intrinsically disordered domains, of the critical silencing factor SPEN. Our results suggest a new model for X chromosome inactivation, in which Xist RNA induces macromolecular crowding of heterochromatinizing proteins near distinct sites which ultimately increases their density throughout the chromosome. This mechanism enables deterministic gene silencing without the need for Xist ribonucleoprotein complex-chromatin interactions at each target gene.
]]></description>
<dc:creator>Markaki, Y.</dc:creator>
<dc:creator>Chong, J. G.</dc:creator>
<dc:creator>Luong, C.</dc:creator>
<dc:creator>Tan, S. Y. X.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Jacobson, E. C.</dc:creator>
<dc:creator>Maestrini, D.</dc:creator>
<dc:creator>Dror, I.</dc:creator>
<dc:creator>Mistry, B. A.</dc:creator>
<dc:creator>Schoeneberg, J.</dc:creator>
<dc:creator>Banerjee, A.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:creator>Chou, T.</dc:creator>
<dc:creator>Plath, K.</dc:creator>
<dc:date>2020-11-23</dc:date>
<dc:identifier>doi:10.1101/2020.11.22.393546</dc:identifier>
<dc:title><![CDATA[Xist-seeded nucleation sites form local concentration gradients of silencing proteins to inactivate the X-chromosome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.23.395335v1?rss=1">
<title>
<![CDATA[
Bidirectional redox cycling of phenazine-1-carboxylic acid by Citrobacter portucalensis MBL drives increased nitrate reduction 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.23.395335v1?rss=1</link>
<description><![CDATA[
Phenazines are secreted metabolites that microbes use in diverse ways, from quorum sensing to antimicrobial warfare to energy conservation. Phenazines are able to contribute to these activities due to their redox activity. The physiological consequences of cellular phenazine reduction have been extensively studied, but the counterpart phenazine oxidation has been largely overlooked. Phenazine-1-carboxylic acid (PCA) is common in the environment and readily reduced by its producers. Here, we describe its anaerobic oxidation by Citrobacter portucalensis strain MBL, which was isolated from topsoil in Falmouth, MA, and which does not produce phenazines itself. This activity depends on the availability of a suitable terminal electron acceptor, specifically nitrate or fumarate. When C. portucalensis MBL is provided reduced PCA and either nitrate or fumarate, it continuously oxidizes the PCA. We compared this terminal electron acceptor-dependent PCA-oxidizing activity of C. portucalensis MBL to that of several other {gamma}-proteobacteria with varying capacities to respire nitrate and/or fumarate. We found that PCA oxidation by these strains in a fumarate-or nitrate-dependent manner is decoupled from growth and correlated with their possession of the fumarate or periplasmic nitrate reductases, respectively. We infer that bacterial PCA oxidation is widespread and genetically determined. Notably, reduced PCA enhances the rate of nitrate reduction to nitrite by C. portucalensis MBL beyond the stoichiometric prediction, which we attribute to C. portucalensis MBLs ability to also reduce oxidized PCA, thereby catalyzing a complete PCA redox cycle. This bidirectionality highlights the versatility of PCA as a biological redox agent.

IMPORTANCEPhenazines are increasingly appreciated for their roles in structuring microbial communities. These tricyclic aromatic molecules have been found to regulate gene expression, be toxic, promote antibiotic tolerance, and promote survival under oxygen starvation. In all of these contexts, however, phenazines are studied as electron acceptors. Even if their utility arises primarily from being readily reduced, they would need to be oxidized in order to be recycled. While oxygen and ferric iron can oxidize phenazines abiotically, biotic oxidation of phenazines has not been studied previously. We observed bacteria that readily oxidize phenazine-1-carboxylic acid (PCA) in a nitrate-dependent fashion, concomitantly increasing the rate of nitrate reduction to nitrite. Because nitrate is a prevalent terminal electron acceptor in diverse anoxic environments, including soils, and phenazine-producers are widespread, this observation of linked phenazine and nitrogen redox cycling suggests an underappreciated role for redox-active secreted metabolites in the environment.
]]></description>
<dc:creator>Tsypin, L. M.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2020-11-24</dc:date>
<dc:identifier>doi:10.1101/2020.11.23.395335</dc:identifier>
<dc:title><![CDATA[Bidirectional redox cycling of phenazine-1-carboxylic acid by Citrobacter portucalensis MBL drives increased nitrate reduction]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.25.399287v1?rss=1">
<title>
<![CDATA[
A two-state ribosome and protein model can robustly capture the chemical reaction dynamics of gene expression 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.25.399287v1?rss=1</link>
<description><![CDATA[
We derive phenomenological models of gene expression from a mechanistic description of chemical reactions using an automated model reduction method. Using this method, we get analytical descriptions and computational performance guarantees to compare the reduced dynamics with the full models. We develop a new two-state model with the dynamics of the available free ribosomes in the system and the protein concentration. We show that this new two-state model captures the detailed mass-action kinetics of the chemical reaction network under various biologically plausible conditions on model parameters. On comparing the performance of this model with the commonly used mRNA transcript-protein dynamical model for gene expression, we analytically show that the free ribosome and protein model has superior error and robustness performance.
]]></description>
<dc:creator>Pandey, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2020-11-26</dc:date>
<dc:identifier>doi:10.1101/2020.11.25.399287</dc:identifier>
<dc:title><![CDATA[A two-state ribosome and protein model can robustly capture the chemical reaction dynamics of gene expression]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.29.403055v1?rss=1">
<title>
<![CDATA[
Global architecture of the nucleus in single cells by DNA seqFISH+ and multiplexed immunofluorescence 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.29.403055v1?rss=1</link>
<description><![CDATA[
Identifying the relationships between chromosome structures, chromatin states, and gene expression is an overarching goal of nuclear organization studies. Because individual cells are highly variable at all three levels, it is essential to map all three modalities in the same single cell, a task that has been difficult to accomplish with existing tools. Here, we report the direct super-resolution imaging of over 3,660 chromosomal loci in single mouse embryonic stem cells (mESCs) by DNA seqFISH+, along with 17 chromatin marks by sequential immunofluorescence (IF) and the expression profile of 70 RNAs, in the same cells. We discovered that the nucleus is separated into zones defined by distinct combinatorial chromatin marks. DNA loci and nascent transcripts are enriched at the interfaces between specific nuclear zones, and the level of gene expression correlates with an association between active or nuclear speckle zones. Our analysis also uncovered several distinct mESCs subpopulations with characteristic combinatorial chromatin states that extend beyond known transcriptional states, suggesting that the metastable states of mESCs are more complex than previously appreciated. Using clonal analysis, we show that the global levels of some chromatin marks, such as H3K27me3 and macroH2A1 (mH2A1), are heritable over at least 3-4 generations, whereas other marks fluctuate on a faster time scale. The long-lived chromatin states may represent "hidden variables" that explain the observed functional heterogeneity in differentiation decisions in single mESCs. Our integrated spatial genomics approach can be used to further explore the existence and biological relevance of molecular heterogeneity within cell populations in diverse biological systems.
]]></description>
<dc:creator>Takei, Y.</dc:creator>
<dc:creator>Yun, J.</dc:creator>
<dc:creator>Ollikainen, N.</dc:creator>
<dc:creator>Zheng, S.</dc:creator>
<dc:creator>Pierson, N.</dc:creator>
<dc:creator>White, J.</dc:creator>
<dc:creator>Shah, S.</dc:creator>
<dc:creator>Thomassie, J.</dc:creator>
<dc:creator>Eng, C.-H. L.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:creator>Yuan, G.-C.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:date>2020-11-30</dc:date>
<dc:identifier>doi:10.1101/2020.11.29.403055</dc:identifier>
<dc:title><![CDATA[Global architecture of the nucleus in single cells by DNA seqFISH+ and multiplexed immunofluorescence]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.12.03.410571v1?rss=1">
<title>
<![CDATA[
Stimulus-selective lateral signaling between olfactory afferents enables parallel encoding of distinct CO2 dynamics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.12.03.410571v1?rss=1</link>
<description><![CDATA[
An important problem in sensory processing is how lateral interactions that mediate the integration of information across sensory channels function with respect to stimulus tuning. We demonstrate a novel form of selective crosstalk between specific olfactory channels that occurs between primary olfactory receptor neurons (ORNs). Neurotransmitter release from ORNs can be driven by two distinct sources of excitation, feedforward activity derived from the odorant receptor and lateral input originating from specific subsets of other ORNs. Consequently, levels of presynaptic release can become dissociated from firing rate. Stimulus-selective lateral signaling results in the distributed representation of CO2, a behaviorally important environmental cue that elicits spiking in only a single ORN class, in multiple olfactory channels. Different CO2-responsive channels preferentially transmit distinct stimulus dynamics, thereby expanding the coding bandwidth for CO2. These results generalize to additional odors and olfactory channels, revealing a subnetwork of lateral interactions between ORNs that reshape the spatial and temporal structure of odor representations in a stimulus-specific manner.

One Sentence SummaryA novel subnetwork of stimulus-selective lateral interactions between primary olfactory sensory neurons enables new sensory computations.
]]></description>
<dc:creator>Zocchi, D.</dc:creator>
<dc:creator>Hong, E. J.</dc:creator>
<dc:date>2020-12-03</dc:date>
<dc:identifier>doi:10.1101/2020.12.03.410571</dc:identifier>
<dc:title><![CDATA[Stimulus-selective lateral signaling between olfactory afferents enables parallel encoding of distinct CO2 dynamics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-12-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.12.04.408955v1?rss=1">
<title>
<![CDATA[
Machine Learning-Assisted Directed Evolution Navigates a Combinatorial Epistatic Fitness Landscape with Minimal Screening Burden 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.12.04.408955v1?rss=1</link>
<description><![CDATA[
Due to screening limitations, in directed evolution (DE) of proteins it is rarely feasible to fully evaluate combinatorial mutant libraries made by mutagenesis at multiple sites. Instead, DE often involves a single-step greedy optimization in which the mutation in the highest-fitness variant identified in each round of single-site mutagenesis is fixed. However, because the effects of a mutation can depend on the presence or absence of other mutations, the efficiency and effectiveness of a single-step greedy walk is influenced by both the starting variant and the order in which beneficial mutations are identified--the process is path-dependent. We recently demonstrated a path-independent machine learning-assisted approach to directed evolution (MLDE) that allows in silico screening of full combinatorial libraries made by simultaneous saturation mutagenesis, thus explicitly capturing the effects of cooperative mutations and bypassing the path-dependence that can limit greedy optimization. Here, we thoroughly investigate and optimize an MLDE workflow by testing a number of design considerations of the MLDE pipeline. Specifically, we (1) test the effects of different encoding strategies on MLDE efficiency, (2) integrate new models and a training procedure more amenable to protein engineering tasks, and (3) incorporate training set design strategies to avoid information-poor low-fitness protein variants ("holes") in the training data. When applied to an epistatic, hole-filled, four-site combinatorial fitness landscape of protein G domain B1 (GB1), the resulting focused training MLDE (ftMLDE) protocol achieved the global fitness maximum up to 92% of the time at a total screening burden of 470 variants. In contrast, minimal-screening-burden single-step greedy optimization over the GB1 fitness landscape reached the global maximum just 1.2% of the time; ftMLDE matching this minimal screening burden (80 total variants) achieved the global optimum up to 9.6% of the time with a 49% higher expected maximum fitness achieved. To facilitate further development of MLDE, we present the MLDE software package (https://github.com/fhalab/MLDE), which is designed for use by protein engineers without computational or machine learning expertise.
]]></description>
<dc:creator>Wittmann, B. J.</dc:creator>
<dc:creator>Yue, Y.</dc:creator>
<dc:creator>Arnold, F. H.</dc:creator>
<dc:date>2020-12-04</dc:date>
<dc:identifier>doi:10.1101/2020.12.04.408955</dc:identifier>
<dc:title><![CDATA[Machine Learning-Assisted Directed Evolution Navigates a Combinatorial Epistatic Fitness Landscape with Minimal Screening Burden]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-12-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.12.08.388942v1?rss=1">
<title>
<![CDATA[
Indoxyl sulfate, a gut microbiome-derived uremic toxin, is associated with psychic anxiety and its functional magnetic resonance imaging-based neurologic signature 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.12.08.388942v1?rss=1</link>
<description><![CDATA[
BackgroundIt is unknown whether indoles, metabolites of tryptophan that are derived entirely from bacterial metabolism in the gut, are associated with symptoms of depression and anxiety.

MethodsSerum samples (baseline, 12 weeks) were drawn from participants (n=196) randomized to treatment with cognitive behavioral therapy (CBT), escitalopram, or duloxetine for major depressive disorder.

ResultsBaseline indoxyl sulfate abundance was positively correlated with severity of psychic anxiety and total anxiety and with resting state functional connectivity to a network that processes aversive stimuli (which includes the subcallosal cingulate cortex (SCC-FC), bilateral anterior insula, right anterior midcingulate cortex, and the right premotor areas). The relation between indoxyl sulfate and psychic anxiety was mediated only through the metabolites effect on the SCC-FC with the premotor area. Baseline indole abundances were unrelated to post-treatment outcome measures, which suggests that CBT and antidepressant medications relieve anxiety via mechanisms unrelated to gut microbiota.

ConclusionsA peripheral gut microbiome-derived metabolite was associated with altered neural processing and with psychiatric symptom (anxiety) in humans, which provides further evidence that gut microbiome disruption can contribute to neuropsychiatric disorders that may require different therapeutic approaches.
]]></description>
<dc:creator>Brydges, C. R.</dc:creator>
<dc:creator>Fiehn, O.</dc:creator>
<dc:creator>Mayberg, H. S.</dc:creator>
<dc:creator>Schreiber, H.</dc:creator>
<dc:creator>Mahmoudian Dehkordi, S.</dc:creator>
<dc:creator>Bhattacharyya, S.</dc:creator>
<dc:creator>Cha, J.</dc:creator>
<dc:creator>Choi, K. S.</dc:creator>
<dc:creator>Craighead, W. E.</dc:creator>
<dc:creator>Krishnan, R. R.</dc:creator>
<dc:creator>Rush, A. J.</dc:creator>
<dc:creator>Dunlop, B. W.</dc:creator>
<dc:creator>Kaddurah-Daouk, R.</dc:creator>
<dc:date>2020-12-09</dc:date>
<dc:identifier>doi:10.1101/2020.12.08.388942</dc:identifier>
<dc:title><![CDATA[Indoxyl sulfate, a gut microbiome-derived uremic toxin, is associated with psychic anxiety and its functional magnetic resonance imaging-based neurologic signature]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-12-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.12.08.416503v1?rss=1">
<title>
<![CDATA[
The context-dependent, combinatorial logic of BMP signaling 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.12.08.416503v1?rss=1</link>
<description><![CDATA[
Cell-cell communication systems typically comprise families of ligand and receptor variants that function together in combinations. Pathway activation depends in a complex way on which ligands are present and what receptors are expressed by the signal-receiving cell. To understand the combinatorial logic of such a system, we systematically measured pairwise Bone Morphogenetic Protein (BMP) ligand interactions in cells with varying receptor expression. Ligands could be classified into equivalence groups based on their profile of positive and negative synergies with other ligands. These groups varied with receptor expression, explaining how ligands can functionally replace each other in one context but not another. Context-dependent combinatorial interactions could be explained by a biochemical model based on competitive formation of alternative signaling complexes with distinct activities. Together, these results provide insights into the roles of BMP combinations in developmental and therapeutic contexts and establish a framework for analyzing other combinatorial, context-dependent signaling systems.
]]></description>
<dc:creator>Klumpe, H. E.</dc:creator>
<dc:creator>Langley, M. A.</dc:creator>
<dc:creator>Linton, J. M.</dc:creator>
<dc:creator>Su, C. J.</dc:creator>
<dc:creator>Antebi, Y. E.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:date>2020-12-08</dc:date>
<dc:identifier>doi:10.1101/2020.12.08.416503</dc:identifier>
<dc:title><![CDATA[The context-dependent, combinatorial logic of BMP signaling]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-12-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.12.20.423607v1?rss=1">
<title>
<![CDATA[
In vitro characterization of engineered red blood cells as potent viral traps against HIV-1 and SARS-CoV-2 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.12.20.423607v1?rss=1</link>
<description><![CDATA[
Engineered red blood cells (RBCs) expressing viral receptors could be used therapeutically as viral traps as RBCs lack nuclei and other organelles required for viral replication. Here we show that the combination of a powerful erythroid-specific expression system and transgene codon optimization yields high expression levels of the HIV-1 receptors CD4 and CCR5, as well as a CD4-glycophorin A (CD4-GpA) fusion protein on enucleated RBCs. Engineered RBCs expressing CD4 and CCR5 were efficiently infected by HIV-1, but CD4 or CD4-GpA expression in the absence of CCR5 was sufficient to potently neutralize HIV-1 in vitro. To facilitate continuous large-scale production of engineered RBCs, we generated erythroblast cell lines stably expressing CD4-GpA or ACE2-GpA fusion proteins, which produced potent RBC viral traps against HIV-1 and SARS-CoV-2. Our results suggest that this approach warrants further investigation as a potential treatment against viral infections.
]]></description>
<dc:creator>Hoffmann, M. A. G.</dc:creator>
<dc:creator>Kieffer, C.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2020-12-21</dc:date>
<dc:identifier>doi:10.1101/2020.12.20.423607</dc:identifier>
<dc:title><![CDATA[In vitro characterization of engineered red blood cells as potent viral traps against HIV-1 and SARS-CoV-2]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-12-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.12.21.423854v1?rss=1">
<title>
<![CDATA[
Liver Electrical Impedance Tomography for Early Identification of Fatty Infiltrate in Obesity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.12.21.423854v1?rss=1</link>
<description><![CDATA[
Non-alcoholic fatty liver disease (NAFLD) is endemic in developed countries and is one of the most common causes of cardiometabolic diseases in overweight/obese individuals. While liver biopsy or magnetic resonance imaging (MRI) is the current gold standard to diagnose NAFLD, the former is prone to bleeding and the latter is costly. We hereby demonstrated liver electrical impedance tomography (EIT) as a non-invasive and portable detection method for fatty infiltrate. We enrolled 19 subjects (15 females and 4 males; 27 to 74 years old) to undergo liver MRI scans, followed by EIT measurements via a multi-electrode array. The liver MRI scans provided subject-specific a priori knowledge of the liver boundary conditions for segmentation and EIT reconstruction, and the 3-D multi-echo MRI data quantified liver proton-density fat fraction (PDFF%) as a recognized reference standard for validating liver fat infiltrate. Using acquired voltage data and the reconstruction algorithm for the EIT imaging, we computed the absolute conductivity distribution of abdomen in 2-D. Correlation analyses were performed to compare the individual EIT conductivity vs. MRI PDFF with their demographics in terms of gender, BMI (kg{middle dot}m-2), age (years), waist circumference (cm), height (cm), and weight (kg). Our results indicate that EIT conductivity (S{middle dot}m-1) and liver MRI for PDFF were not correlated with the demographics, whereas the decrease in EIT conductivity was correlated with the increase in MRI PDFF (R = - 0.69, p= 0.003). Thus, EIT conductivity holds promise for developing a non-invasive, portable, and quantitative method to detect fatty liver disease.
]]></description>
<dc:creator>Chang, C.-C.</dc:creator>
<dc:creator>Huang, Z.-Y.</dc:creator>
<dc:creator>Shih, S.-F.</dc:creator>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>Ko, A.</dc:creator>
<dc:creator>Cui, Q.</dc:creator>
<dc:creator>Cavallero, S.</dc:creator>
<dc:creator>Das, S.</dc:creator>
<dc:creator>Thames, G.</dc:creator>
<dc:creator>Bui, A.</dc:creator>
<dc:creator>Jacobs, J. P.</dc:creator>
<dc:creator>Pajukanta, P.</dc:creator>
<dc:creator>Wu, H.</dc:creator>
<dc:creator>Tai, Y.-C.</dc:creator>
<dc:creator>Li, Z.</dc:creator>
<dc:creator>Hsiai, T.</dc:creator>
<dc:date>2020-12-22</dc:date>
<dc:identifier>doi:10.1101/2020.12.21.423854</dc:identifier>
<dc:title><![CDATA[Liver Electrical Impedance Tomography for Early Identification of Fatty Infiltrate in Obesity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-12-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.07.425611v1?rss=1">
<title>
<![CDATA[
Neural correlates of orbital telorism 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.07.425611v1?rss=1</link>
<description><![CDATA[
Orbital telorism, the interocular distance, is a clinically informative and in extremes is considered a minor physical anomaly. While its extremes, hypo- and hypertelorism, have been linked to disorders often related to cognitive ability, little is known about the neural correlates of normal variation of telorism within the general population. We derived measures of orbital telorism from cranial magnetic resonance imaging (MRI) by calculating the distance between the eyeball center of gravity in two population-based datasets (N=5,653, N=29,824, Mean age 64.66, 63.75 years). This measure was found to be related grey matter tissue density within numerous regions of the brain, including, but surprisingly not limited to, the frontal regions, in both positive and negative directions. Additionally, telorism was related to several cognitive functions, such as Perdue Pegboard test (Beta, P-value, (CI95%) -0.02, 1.63x10-7(-0.03;-0.01)) and fluid intelligence (0.02, 4.75x10-06 (0.01:0.02)), with some relationships driven by individuals with a smaller orbital telorism. This is reflective of the higher prevalence of hypo-telorism in developmental disorders, specifically those that accompany lower cognitive lower functioning. This study suggests, despite previous links only made in clinical extremes, that orbital telorism holds some relation to structural brain development and cognitive function in the general population. This relationship is likely driven by shared developmental periods.
]]></description>
<dc:creator>Pawlak, M. A.</dc:creator>
<dc:creator>Knol, M. J.</dc:creator>
<dc:creator>Vernoiij, M. W.</dc:creator>
<dc:creator>Ikram, M. A.</dc:creator>
<dc:creator>Adams, H.</dc:creator>
<dc:creator>Evans, T. E.</dc:creator>
<dc:date>2021-01-08</dc:date>
<dc:identifier>doi:10.1101/2021.01.07.425611</dc:identifier>
<dc:title><![CDATA[Neural correlates of orbital telorism]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.08.425924v1?rss=1">
<title>
<![CDATA[
CYK-1/Formin activation in cortical RhoA signaling centers promotes organismal left-right symmetry breaking 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.08.425924v1?rss=1</link>
<description><![CDATA[
1Proper left-right symmetry breaking is essential for animal development and in many species the actin cytoskeleton plays an instrumental role in this process. Active torque generation in the actomyosin layer promotes left-right symmetry breaking in C. elegans embryos by driving chiral counter-rotating cortical flows. While both Formins and Myosins have been implied in left-right symmetry breaking, and both can rotate actin filaments in vitro, it remains unclear if active torques in the actomyosin cortex are generated by Formins, Myosins, or both. We combined the strength of C. elegans genetics with quantitative imaging and thin film, chiral active fluid theory to show that, while Non-Muscle Myosin II activity drives cortical actomyosin flows, it is permissive for chiral counter-rotation and dispensable for chiral symmetry breaking of cortical flows. Instead, we find that CYK-1/Formin activation in RhoA foci is instructive for chiral counter-rotation and promotes in-plane, active torque generation in the actomyosin cortex. Notably, we observe that artificially generated large active RhoA patches undergo rotations with consistent handedness in a CYK-1/Formin-dependent manner. Altogether, we conclude that, CYK-1/Formin-dependent active torque generation facilitates chiral symmetry breaking of actomyosin flows and drives organismal left-right symmetry breaking in the nematode worm.

2 SignificanceActive torque generation in the actin cytoskeleton has been implicated in driving left-right symmetry breaking of developing embryos, but which molecules generate the active torque and how active torque generation is organized subcellularly remains unclear. This study shows that cortical Formin, recruited to cortical regions where RhoA signaling is active, promotes active torque generation in the actomyosin layer. We find that active torque tends to locally rotate the cortex in a clockwise fashion, which drives the emergence of chiral counter-rotating flows with consistent handedness and facilitates left-right symmetry breaking of C. elegans embryos.
]]></description>
<dc:creator>Middelkoop, T. C.</dc:creator>
<dc:creator>Garcia-Baucells, J.</dc:creator>
<dc:creator>Quintero-Cadena, P.</dc:creator>
<dc:creator>Pimpale, L. G.</dc:creator>
<dc:creator>Yazdi, S.</dc:creator>
<dc:creator>Sternberg, P.</dc:creator>
<dc:creator>Gross, P.</dc:creator>
<dc:creator>Grill, S. W.</dc:creator>
<dc:date>2021-01-08</dc:date>
<dc:identifier>doi:10.1101/2021.01.08.425924</dc:identifier>
<dc:title><![CDATA[CYK-1/Formin activation in cortical RhoA signaling centers promotes organismal left-right symmetry breaking]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.08.425961v1?rss=1">
<title>
<![CDATA[
Super-Resolution Label-free Volumetric Vibrational Imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.08.425961v1?rss=1</link>
<description><![CDATA[
Innovations in high-resolution optical imaging have allowed visualization of nanoscale biological structures and connections. However, super-resolution fluorescence techniques, including both optics-oriented and sample-expansion based, are limited in quantification and throughput especially in tissues from photobleaching or quenching of the fluorophores, and low-efficiency or non-uniform delivery of the probes. Here, we report a general sample-expansion vibrational imaging strategy, termed VISTA, for scalable label-free high-resolution interrogations of protein-rich biological structures with resolution down to 82 nm. VISTA achieves decent three-dimensional image quality through optimal retention of endogenous proteins, isotropic sample expansion, and deprivation of scattering lipids. Free from probe-labeling associated issues, VISTA offers unbiased and high-throughput tissue investigations. With correlative VISTA and immunofluorescence, we further validated the imaging specificity of VISTA and trained an image-segmentation model for label-free multi-component and volumetric prediction of nucleus, blood vessels, neuronal cells and dendrites in complex mouse brain tissues. VISTA could hence open new avenues for versatile biomedical studies.
]]></description>
<dc:creator>Qian, C.</dc:creator>
<dc:creator>Miao, K.</dc:creator>
<dc:creator>Lin, L.-E.</dc:creator>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>Du, J.</dc:creator>
<dc:creator>Wei, L.</dc:creator>
<dc:date>2021-01-09</dc:date>
<dc:identifier>doi:10.1101/2021.01.08.425961</dc:identifier>
<dc:title><![CDATA[Super-Resolution Label-free Volumetric Vibrational Imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.11.426256v1?rss=1">
<title>
<![CDATA[
High levels of Dorsal transcription factor downregulate, not promote, snail expression by regulating enhancer action 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.11.426256v1?rss=1</link>
<description><![CDATA[
In Drosophila embryos, genes expressed along the dorsal-ventral axis are responsive to concentration of the Dorsal (Dl) transcription factor, which varies in space; however, levels of this morphogen also build over time. Since expression of high-threshold Dl target genes such as snail (sna) is supported before Dl levels peak, it is unclear what role increasing levels have if any. Here we investigated action of two enhancers that control sna expression in embryos, demonstrating using genome editing that Dl binding sites within one enhancer located promoter proximally, sna.prox, can limit the ability of the other distally-located enhancer, sna.dis, to increase sna levels. In addition, MS2-MCP live imaging was used to study sna transcription rate in wildtype, dl heterozygote, and a background in which a photo-sensitive degron is fused to Dl (dl-BLID). The results demonstrate that, when Dl levels are high, Dl acts through sna.prox to limit the activity of sna.dis and thereby influence sna transcription rate. In contrast, when Dl levels are kept low using dl-BLID, sna.prox positively influences sna transcription rate. Collectively, our data support the view that Dls effect on gene expression changes over time, switching from promoting sna expression at low concentration to dampening sna expression at high concentration by regulating enhancer interactions. We propose this differential action of the Dl morphogen is likely supported by occupancy of this factor first to high and then low affinity binding sites over time as Dl levels rise to coordinate action of these two co-acting enhancers.

Significance statementA gradient of the maternal transcription factor Dorsal is important for establishing spatial expression of target genes along the dorsal-ventral axis of Drosophila embryos. Dorsal levels are also dynamic as nuclear concentration builds in time. Surprisingly, expression of high-threshold target genes such as snail is supported before levels peak, raising the question why levels continue to build. Our data support the view that peak Dorsal levels act to preferentially support activity of one enhancer over another to effectively decrease snail expression. In addition, while the morphogen Dorsal acts early to support gene expression, later it effectively acts as a damper to limit gene expression. Our results suggest other morphogens also have effects on gene expression that change over time.
]]></description>
<dc:creator>Irizarry, J.</dc:creator>
<dc:creator>McGehee, J.</dc:creator>
<dc:creator>Stathopoulos, A.</dc:creator>
<dc:date>2021-01-11</dc:date>
<dc:identifier>doi:10.1101/2021.01.11.426256</dc:identifier>
<dc:title><![CDATA[High levels of Dorsal transcription factor downregulate, not promote, snail expression by regulating enhancer action]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.15.426911v1?rss=1">
<title>
<![CDATA[
mRNA vaccine-elicited antibodies to SARS-CoV-2 and circulating variants 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.15.426911v1?rss=1</link>
<description><![CDATA[
To date severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has infected over 100 million individuals resulting in over two million deaths. Many vaccines are being deployed to prevent coronavirus disease 2019 (COVID-19) including two novel mRNA-based vaccines1,2. These vaccines elicit neutralizing antibodies and appear to be safe and effective, but the precise nature of the elicited antibodies is not known3-6. Here we report on the antibody and memory B cell responses in a cohort of 20 volunteers who received either the Moderna (mRNA-1273) or Pfizer-BioNTech (BNT162b2) vaccines. Consistent with prior reports, 8 weeks after the second vaccine injection volunteers showed high levels of IgM, and IgG anti-SARS-CoV-2 spike protein (S) and receptor binding domain (RBD) binding titers3,5,6. Moreover, the plasma neutralizing activity, and the relative numbers of RBD-specific memory B cells were equivalent to individuals who recovered from natural infection7,8. However, activity against SARS-CoV-2 variants encoding E484K or N501Y or the K417N:E484K:N501Y combination was reduced by a small but significant margin. Consistent with these findings, vaccine-elicited monoclonal antibodies (mAbs) potently neutralize SARS-CoV-2, targeting a number of different RBD epitopes in common with mAbs isolated from infected donors. Structural analyses of mAbs complexed with S trimer suggest that vaccine- and virus-encoded S adopts similar conformations to induce equivalent anti-RBD antibodies. However, neutralization by 14 of the 17 most potent mAbs tested was reduced or abolished by either K417N, or E484K, or N501Y mutations. Notably, the same mutations were selected when recombinant vesicular stomatitis virus (rVSV)/SARS-CoV-2 S was cultured in the presence of the vaccine elicited mAbs. Taken together the results suggest that the monoclonal antibodies in clinical use should be tested against newly arising variants, and that mRNA vaccines may need to be updated periodically to avoid potential loss of clinical efficacy.
]]></description>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>Schmidt, F.</dc:creator>
<dc:creator>Weisblum, Y.</dc:creator>
<dc:creator>Muecksch, F.</dc:creator>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Finkin, S.</dc:creator>
<dc:creator>Schaefer-Babajew, D.</dc:creator>
<dc:creator>Cipolla, M.</dc:creator>
<dc:creator>Gaebler, C.</dc:creator>
<dc:creator>Lieberman, J. A.</dc:creator>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Abernathy, M. E.</dc:creator>
<dc:creator>Huey-Tubman, K. E.</dc:creator>
<dc:creator>Hurley, A.</dc:creator>
<dc:creator>Turroja, M.</dc:creator>
<dc:creator>West, K. A.</dc:creator>
<dc:creator>Gordon, K.</dc:creator>
<dc:creator>Millard, K. G.</dc:creator>
<dc:creator>Ramos, V.</dc:creator>
<dc:creator>Silva, J. D.</dc:creator>
<dc:creator>Xu, J.</dc:creator>
<dc:creator>Colbert, R. A.</dc:creator>
<dc:creator>Patel, R.</dc:creator>
<dc:creator>Dizon, J. P.</dc:creator>
<dc:creator>Unson-O'Brien, C.</dc:creator>
<dc:creator>Shimeliovich, I.</dc:creator>
<dc:creator>Gazumyan, A.</dc:creator>
<dc:creator>Caskey, M.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Casellas, R.</dc:creator>
<dc:creator>Hatziioannou, T.</dc:creator>
<dc:creator>Bieniasz, P. D.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:date>2021-01-19</dc:date>
<dc:identifier>doi:10.1101/2021.01.15.426911</dc:identifier>
<dc:title><![CDATA[mRNA vaccine-elicited antibodies to SARS-CoV-2 and circulating variants]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.16.426941v1?rss=1">
<title>
<![CDATA[
Intracranial electrical stimulation alters meso-scale network integration as a function of network topology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.16.426941v1?rss=1</link>
<description><![CDATA[
Human brain dynamics are organized into a multi-scale network structure that contains multiple tight-knit, meso-scale communities. Recent work has demonstrated that many psychological capacities, as well as impairments in cognitive function secondary to damage, can be mapped onto organizing principles at this mesoscopic scale. However, we still dont know the rules that govern the dynamic interactions between regions that are constrained by the topology of the broader network. In this preregistered study, we utilized a unique human dataset in which whole brain BOLD-fMRI activity was recorded simultaneously with intracranial electrical stimulation, to characterize the effects of direct neural stimulation on the dynamic reconfiguration of the broader network. Direct neural stimulation increased the extent to which the stimulation sites own mesoscale community integrated with the rest of the brain. Further, we found that these network changes depended on the topological role of the stimulation site itself: stimulating regions with high participation coefficients led to global integration, whereas stimulating sites with low participation coefficients integrated that regions own community with the rest of the brain. These findings provide direct causal evidence for how network topology shapes and constrains inter-regional coordination, and suggest applications for targeted therapeutic interventions in patients with deep-brain stimulation.
]]></description>
<dc:creator>Thompson, W. H.</dc:creator>
<dc:creator>Esteban, O.</dc:creator>
<dc:creator>Oya, H.</dc:creator>
<dc:creator>Nair, R.</dc:creator>
<dc:creator>Eberhardt, F.</dc:creator>
<dc:creator>Dubois, J.</dc:creator>
<dc:creator>Poldrack, R. A.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:creator>Shine, J. M.</dc:creator>
<dc:date>2021-01-19</dc:date>
<dc:identifier>doi:10.1101/2021.01.16.426941</dc:identifier>
<dc:title><![CDATA[Intracranial electrical stimulation alters meso-scale network integration as a function of network topology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.16.426971v1?rss=1">
<title>
<![CDATA[
Evolution of the cytochrome-bd type oxygen reductase superfamily and the function of cydAA in Archaea 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.16.426971v1?rss=1</link>
<description><![CDATA[
Cytochrome bd-type oxygen reductases (cytbd) belong to one of three enzyme superfamilies that catalyze oxygen reduction to water. They are widely distributed in Bacteria and Archaea, but the full extent of their biochemical diversity is unknown. Here we used phylogenomics to identify 3 families and several subfamilies within the cytbd superfamily. The core architecture shared by all members of the superfamily consists of four transmembrane helices that bind two active site hemes, which are responsible for oxygen reduction. While previously characterized cytochrome bd-type oxygen reductases use quinol as an electron donor to reduce oxygen, sequence analysis shows that only one of the identified families has a conserved quinol binding site. The other families are missing this feature, suggesting that they use an alternative electron donor. Multiple gene duplication events were identified within the superfamily, resulting in significant evolutionary and structural diversity. The CydAA cytbd, found exclusively in Archaea, is formed by the co-association of two superfamily paralogs. We heterologously expressed CydAA from Caldivirga maquilingensis and demonstrated that it performs oxygen reduction with quinol as an electron donor. Strikingly, CydAA is the first isoform of cytbd containing only b-type hemes shown to be active when isolated, demonstrating that oxygen reductase activity in this superfamily is not dependent on heme d.
]]></description>
<dc:creator>Murali, R.</dc:creator>
<dc:creator>Gennis, R. B.</dc:creator>
<dc:creator>Hemp, J.</dc:creator>
<dc:date>2021-01-17</dc:date>
<dc:identifier>doi:10.1101/2021.01.16.426971</dc:identifier>
<dc:title><![CDATA[Evolution of the cytochrome-bd type oxygen reductase superfamily and the function of cydAA in Archaea]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.18.427191v1?rss=1">
<title>
<![CDATA[
Drosophila local search emerges from iterative odometry of consecutive run lengths. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.18.427191v1?rss=1</link>
<description><![CDATA[
The ability to keep track of ones location in space is a critical behavior for animals navigating to and from a salient location, and its computational basis is now beginning to be unraveled. Here, we tracked flies in a ring-shaped channel as they executed bouts of search triggered by optogenetic activation of sugar receptors. Unlike experiments in open field arenas, which produce highly tortuous search trajectories, our geometrically constrained paradigm enabled us to monitor flies decisions to move toward or away from the fictive food. Our results suggest that flies use path integration to remember the location of a food site even after it has disappeared, and that flies can remember the location of a former food site even after walking around the arena one or more times. To determine the behavioral algorithms underlying Drosophila search, we developed multiple state transition models and found that flies likely accomplish path integration by combining odometry and compass navigation to keep track of their position relative to the fictive food. Our results indicate that whereas flies re-zero their path integrator at food when only one feeding site is present, they adjust their path integrator to a central location between sites when experiencing food at two or more locations. Together, this work provides a simple experimental paradigm and theoretical framework to advance investigations of the neural basis of path integration.
]]></description>
<dc:creator>Behbahani, A. H.</dc:creator>
<dc:creator>Palmer, E. H.</dc:creator>
<dc:creator>Corfas, R. A.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:date>2021-01-19</dc:date>
<dc:identifier>doi:10.1101/2021.01.18.427191</dc:identifier>
<dc:title><![CDATA[Drosophila local search emerges from iterative odometry of consecutive run lengths.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.20.427480v1?rss=1">
<title>
<![CDATA[
Direct simulation of a stochastically driven multi-step birth-death process 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.20.427480v1?rss=1</link>
<description><![CDATA[
1The description of transcription as a stochastic process provides a framework for the analysis of intrinsic and extrinsic noise in cells. To better understand the behaviors and possible extensions of existing models, we design an exact stochastic simulation algorithm for a multimolecular transcriptional system with an Ornstein-Uhlenbeck birth rate that is implemented via a special function-based time-stepping algorithm. We demonstrate that its joint copy-number distributions reduce to analytically well-studied cases in several limiting regimes, and suggest avenues for generalizations.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2021-01-21</dc:date>
<dc:identifier>doi:10.1101/2021.01.20.427480</dc:identifier>
<dc:title><![CDATA[Direct simulation of a stochastically driven multi-step birth-death process]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.22.427567v1?rss=1">
<title>
<![CDATA[
Bispecific antibody prevents SARS-CoV-2 escape and protects mice from disease 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.22.427567v1?rss=1</link>
<description><![CDATA[
Neutralizing antibodies targeting the receptor binding domain (RBD) of the SARS-CoV-2 Spike (S) are among the most promising approaches against coronavirus disease 2019 (COVID-19)1,2. We developed a bispecific, IgG1-like molecule (CoV-X2) based on two antibodies derived from COVID-19 convalescent donors, C121 and C1353. CoV-X2 simultaneously binds two independent sites on the RBD and, unlike its parental antibodies, prevents detectable S binding to Angiotensin-Converting Enzyme 2 (ACE2), the virus cellular receptor. Furthermore, CoV-X2 neutralizes SARS-CoV-2 and its variants of concern, as well as the escape mutants generated by the parental monoclonals. In a novel animal model of SARS-CoV-2 infection with lung inflammation, CoV-X2 protects mice from disease and suppresses viral escape. Thus, simultaneous targeting of non-overlapping RBD epitopes by IgG-like bispecific antibodies is feasible and effective, combining into a single molecule the advantages of antibody cocktails.
]]></description>
<dc:creator>De Gasparo, R.</dc:creator>
<dc:creator>Pedotti, M.</dc:creator>
<dc:creator>Simonelli, L.</dc:creator>
<dc:creator>Nickl, P.</dc:creator>
<dc:creator>Muecksch, F.</dc:creator>
<dc:creator>Lorenzi, J. C. C.</dc:creator>
<dc:creator>Mazzola, F.</dc:creator>
<dc:creator>Magri, D.</dc:creator>
<dc:creator>Michalcikova, T.</dc:creator>
<dc:creator>Haviernik, J.</dc:creator>
<dc:creator>Honig, V.</dc:creator>
<dc:creator>Cassaniti, I.</dc:creator>
<dc:creator>Percivalle, E.</dc:creator>
<dc:creator>Mrazkova, B.</dc:creator>
<dc:creator>Polakova, N.</dc:creator>
<dc:creator>Fortova, A.</dc:creator>
<dc:creator>Tureckova, J.</dc:creator>
<dc:creator>Iatsiuk, V.</dc:creator>
<dc:creator>Di Girolamo, S.</dc:creator>
<dc:creator>Palus, M.</dc:creator>
<dc:creator>Zudova, D.</dc:creator>
<dc:creator>Bednar, P.</dc:creator>
<dc:creator>Bukova, I.</dc:creator>
<dc:creator>Bianchini, F.</dc:creator>
<dc:creator>Mehn, D.</dc:creator>
<dc:creator>Nencka, R.</dc:creator>
<dc:creator>Strakova, P.</dc:creator>
<dc:creator>Pavlis, O.</dc:creator>
<dc:creator>Rozman, J.</dc:creator>
<dc:creator>Gioria, S.</dc:creator>
<dc:creator>Sammartino, J. C.</dc:creator>
<dc:creator>Giardina, F.</dc:creator>
<dc:creator>Gaiarsa, S.</dc:creator>
<dc:creator>Hammarström, Q. P.</dc:creator>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Piralla, A.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Baldanti, F.</dc:creator>
<dc:creator>Calzolai, L.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:creator>Bieniasz, P. D.</dc:creator>
<dc:creator>Hatziioannou, T.</dc:creator>
<dc:date>2021-01-22</dc:date>
<dc:identifier>doi:10.1101/2021.01.22.427567</dc:identifier>
<dc:title><![CDATA[Bispecific antibody prevents SARS-CoV-2 escape and protects mice from disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.22.427725v1?rss=1">
<title>
<![CDATA[
Measuring gas vesicle dimensions by electron microscopy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.22.427725v1?rss=1</link>
<description><![CDATA[
Gas vesicles (GVs) are cylindrical or spindle-shaped protein nanostructures filled with air and used for flotation by various cyanobacteria, heterotrophic bacteria, and Archaea. Recently, GVs have gained interest in biotechnology applications due to their ability to serve as imaging agents and actuators for ultrasound, magnetic resonance and several optical techniques. The diameter of GVs is a crucial parameter contributing to their mechanical stability, buoyancy function and evolution in host cells, as well as their properties in imaging applications. Despite its importance, reported diameters for the same types of GV differ depending on the method used for its assessment. Here, we provide an explanation for these discrepancies and utilize electron microscopy (EM) techniques to accurately estimate the diameter of the most commonly studied types of GVs. We show that during air drying on the EM grid, GVs flatten, leading to a ~1.5-fold increase in their apparent diameter. We demonstrate that GVs diameter can be accurately determined by direct measurements from cryo-EM samples or alternatively indirectly derived from widths of flat collapsed and negatively stained GVs. Our findings help explain the inconsistency in previously reported data and provide accurate methods to measure GV dimensions.
]]></description>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Metskas, L. A.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Hurt, R. C.</dc:creator>
<dc:creator>Lu, G. J.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2021-01-22</dc:date>
<dc:identifier>doi:10.1101/2021.01.22.427725</dc:identifier>
<dc:title><![CDATA[Measuring gas vesicle dimensions by electron microscopy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.22.427844v1?rss=1">
<title>
<![CDATA[
Whole Animal Multiplexed Single-Cell RNA-Seq Reveals Plasticity of Clytia Medusa Cell Types 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.22.427844v1?rss=1</link>
<description><![CDATA[
We present an organism-wide, transcriptomic cell atlas of the hydrozoan medusa Clytia hemisphaerica, and determine how its component cell types respond to starvation. Utilizing multiplexed scRNA-seq, in which individual animals were indexed and pooled from control and perturbation conditions into a single sequencing run, we avoid artifacts from batch effects and are able to discern shifts in cell state in response to organismal perturbations. This work serves as a foundation for future studies of development, function, and plasticity in a genetically tractable jellyfish species. Moreover, we introduce a powerful workflow for high-resolution, whole animal, multiplexed single-cell genomics (WHAM-seq) that is readily adaptable to other traditional or non-traditional model organisms.
]]></description>
<dc:creator>Chari, T.</dc:creator>
<dc:creator>Weissbourd, B.</dc:creator>
<dc:creator>Gehring, J.</dc:creator>
<dc:creator>Ferraioli, A.</dc:creator>
<dc:creator>Leclere, L.</dc:creator>
<dc:creator>Herl, M.</dc:creator>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>Chevalier, S.</dc:creator>
<dc:creator>Copley, R. R.</dc:creator>
<dc:creator>Houliston, E.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2021-01-23</dc:date>
<dc:identifier>doi:10.1101/2021.01.22.427844</dc:identifier>
<dc:title><![CDATA[Whole Animal Multiplexed Single-Cell RNA-Seq Reveals Plasticity of Clytia Medusa Cell Types]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.23.427872v1?rss=1">
<title>
<![CDATA[
From zero to infinity: minimum to maximum diversity of the planet by spatio-parametric Rao's quadratic entropy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.23.427872v1?rss=1</link>
<description><![CDATA[
AimThe majority of work done to gather information on Earth diversity has been carried out by in-situ data, with known issues related to epistemology (e.g., species determination and taxonomy), spatial uncertainty, logistics (time and costs), among others. An alternative way to gather information about spatial ecosystem variability is the use of satellite remote sensing. It works as a powerful tool for attaining rapid and standardized information. Several metrics used to calculate remotely sensed diversity of ecosystems are based on Shannons Information Theory, namely on the differences in relative abundance of pixel reflectances in a certain area. Additional metrics like the Raos quadratic entropy allow the use of spectral distance beside abundance, but they are point descriptors of diversity, namely they can account only for a part of the whole diversity continuum. The aim of this paper is thus to generalize the Raos quadratic entropy by proposing its parameterization for the first time.

InnovationThe parametric Raos quadratic entropy, coded in R, i) allows to represent the whole continuum of potential diversity indices in one formula, and ii) starting from the Raos quadratic entropy, allows to explicitly make use of distances among pixel reflectance values, together with relative abundances.

Main conclusionsThe proposed unifying measure is an integration between abundance- and distance-based algorithms to map the continuum of diversity given a satellite image at any spatial scale.
]]></description>
<dc:creator>Rocchini, D.</dc:creator>
<dc:creator>Marcantonio, M.</dc:creator>
<dc:creator>Da Re, D.</dc:creator>
<dc:creator>Bacaro, G.</dc:creator>
<dc:creator>Feoli, E.</dc:creator>
<dc:creator>Foody, G. M.</dc:creator>
<dc:creator>Harrigan, R. J.</dc:creator>
<dc:creator>Kleijn, D.</dc:creator>
<dc:creator>Iannacito, M.</dc:creator>
<dc:creator>Lenoir, J.</dc:creator>
<dc:creator>Lin, M.</dc:creator>
<dc:creator>Malavasi, M.</dc:creator>
<dc:creator>Marchetto, E.</dc:creator>
<dc:creator>Meyer, R. S.</dc:creator>
<dc:creator>Moudry, V.</dc:creator>
<dc:creator>Schneider, F. D.</dc:creator>
<dc:creator>Simova, P.</dc:creator>
<dc:creator>Thornhill, A. H.</dc:creator>
<dc:creator>Thouverai, E.</dc:creator>
<dc:creator>Vicario, S.</dc:creator>
<dc:creator>Wayne, R. K.</dc:creator>
<dc:creator>Ricotta, C.</dc:creator>
<dc:date>2021-01-25</dc:date>
<dc:identifier>doi:10.1101/2021.01.23.427872</dc:identifier>
<dc:title><![CDATA[From zero to infinity: minimum to maximum diversity of the planet by spatio-parametric Rao's quadratic entropy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.25.428188v1?rss=1">
<title>
<![CDATA[
Benchmarking of lightweight-mapping based single-cell RNA-seq pre-processing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.25.428188v1?rss=1</link>
<description><![CDATA[
We compare and benchmark the two lightweight-mapping tools that have been developed for pre-processing single-cell RNA-seq data, namely the kallisto-bustools and Salmon-Alevin-fry programs. We find that they output similar results, and to the extent that there are differences, they are irrelevant for downstream analysis. However, the Salmon-Alevin-fry program is significantly slower and requires much more memory to run, making it much more expensive to process large datasets limiting its use to larger servers.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2021-01-26</dc:date>
<dc:identifier>doi:10.1101/2021.01.25.428188</dc:identifier>
<dc:title><![CDATA[Benchmarking of lightweight-mapping based single-cell RNA-seq pre-processing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.27.428538v1?rss=1">
<title>
<![CDATA[
Low-cost, scalable, and automated fluid sampling for fluidics applications 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.27.428538v1?rss=1</link>
<description><![CDATA[
We present colosseum, a low-cost, modular, and automated fluid sampling device for scalable fluidic applications. The colosseum fraction collector uses a single motor, can be built for less than $100 using off-the-shelf and 3D-printed components, and can be assembled in less than an hour. Build Instructions and source files are available at https://github.com/pachterlab/colosseum.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Kil, Y.</dc:creator>
<dc:creator>Min, K. H.</dc:creator>
<dc:creator>Gehring, J.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2021-01-28</dc:date>
<dc:identifier>doi:10.1101/2021.01.27.428538</dc:identifier>
<dc:title><![CDATA[Low-cost, scalable, and automated fluid sampling for fluidics applications]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.28.428658v1?rss=1">
<title>
<![CDATA[
The evolution of interdependence in a four-way mealybug symbiosis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.28.428658v1?rss=1</link>
<description><![CDATA[
Mealybugs are insects that maintain intracellular bacterial symbionts to supplement their nutrientpoor plant sap diets. Some mealybugs have a single betaproteobacterial endosymbiont, a Candidatus Tremblaya species (hereafter Tremblaya) that alone provides the insect with its required nutrients. Other mealybugs have two nutritional endosymbionts that together provide these nutrients, where Tremblaya has gained a gammaproteobacterial partner that resides in the cytoplasm of Tremblaya. Previous work had established that Pseudococcus longispinus mealybugs maintain not one but two species of gammaproteobacterial endosymbionts along with Tremblaya. Preliminary genomic analyses suggested that these two gammaproteobacterial endosymbionts have large genomes with features consistent with a relatively recent origin as insect endosymbionts, but the patterns of genomic complementarity between members of the symbiosis and their relative cellular locations were unknown. Here, using long-read sequencing and various types of microscopy, we show that the two gammaproteobacterial symbionts of P. longispinus are mixed together within Tremblaya cells, and that their genomes are somewhat reduced in size compared to their closest non-endosymbiotic relatives. Both gammaproteobacterial genomes contain thousands of pseudogenes, consistent with a relatively recent shift from a free-living to endosymbiotic lifestyle. Biosynthetic pathways of key metabolites are partitioned in complex interdependent patterns among the two gammaproteobacterial genomes, the Tremblaya genome, and horizontally acquired bacterial genes that are encoded on the mealybug nuclear genome. Although these two gammaproteobacterial endosymbionts have been acquired recently in evolutionary time, they have already evolved co-dependencies with each other, Tremblaya, and their insect host.

SignificanceMealybugs are sap-feeding insects that house between one and three bacterial endosymbionts to supplement their nutritionally poor diets. Many mealybug-bacteria relationships were established tens or hundreds of millions of years ago, and these ancient examples show high levels host-endosymbiont genomic and metabolic integration. Here, we describe the complete genomes and cellular locations for two bacterial endosymbiont which have recently transitioned from a free-living to an intracellular state. Our work reveals the rapid emergence of metabolic interdependence between these two nascent endosymbionts, their partner bacterial co-symbiont in whose cytoplasm they reside, and their insect host cell. Our work confirms that intracellular bacteria rapidly adapt to a host-restricted lifestyle through breakage or loss of redundant genes.
]]></description>
<dc:creator>Garber, A. I.</dc:creator>
<dc:creator>Kupper, M.</dc:creator>
<dc:creator>Laetsch, D. R.</dc:creator>
<dc:creator>Weldon, S. R.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>McCutcheon, J. P.</dc:creator>
<dc:date>2021-01-29</dc:date>
<dc:identifier>doi:10.1101/2021.01.28.428658</dc:identifier>
<dc:title><![CDATA[The evolution of interdependence in a four-way mealybug symbiosis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.02.02.429476v1?rss=1">
<title>
<![CDATA[
LIFE AND WORK OF RESEARCHERS TRAPPED IN THE COVID-19PANDEMIC VICIOUS CYCLE 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.02.02.429476v1?rss=1</link>
<description><![CDATA[
AO_SCPLOWBSTRACTC_SCPLOWCOVID-19 has disrupted researchers work and posed challenges to their life routines. We have surveyed 740 researchers of which 66% experienced a decrease in productivity, 50% indicated increased workload, and 66% reported they have been feeling internal pressure to make progress. Those whose research required physical presence in a lab or the field experienced considerable disruption and productivity decrease. About 82% of this group will try to permanently reduce their work dependency on physical presence. Parents and those taking care of vulnerable dependents have been spending less time on research due to their role conflict. We further observed a gender gap in the overall disruption consequences; more female researchers have been experiencing a reduction in productivity and external pressure to make progress. The results of this study can help institution leaders and policymakers better understand the pandemics challenges for the research community and motivate appropriate measures to instill long-term solutions.
]]></description>
<dc:creator>Ghaffarizadeh, S. A.</dc:creator>
<dc:creator>Ghaffarizadeh, S. A.</dc:creator>
<dc:creator>Behbahani, A. H.</dc:creator>
<dc:creator>Mehdizadeh, M.</dc:creator>
<dc:creator>Olechowski, A.</dc:creator>
<dc:date>2021-02-03</dc:date>
<dc:identifier>doi:10.1101/2021.02.02.429476</dc:identifier>
<dc:title><![CDATA[LIFE AND WORK OF RESEARCHERS TRAPPED IN THE COVID-19PANDEMIC VICIOUS CYCLE]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-02-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.02.03.429301v1?rss=1">
<title>
<![CDATA[
A programmable pAgo nuclease with universal guide and target specificity from the mesophilic bacterium Kurthia massiliensis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.02.03.429301v1?rss=1</link>
<description><![CDATA[
Argonaute proteins are programmable nucleases that are found in both eukaryotes and prokaryotes and provide defense against invading genetic elements. Although some prokaryotic Argonautes (pAgos) were shown to recognize RNA targets in vitro, the majority of studied pAgos have strict specificity toward DNA, which limits their practical use in RNA-centric applications. Here, we describe a unique KmAgo nuclease from the mesophilic bacterium Kurthia massiliensis that can be programmed with either DNA or RNA guides and can precisely cleave both DNA and RNA targets. KmAgo preferentially binds 16-20 nt long 5'-phosphorylated guide molecules with no strict specificity for their sequence and is active in a wide range of temperatures. In bacterial cells, KmAgo is loaded with small DNAs with no obvious sequence preferences suggesting that it can uniformly target genomic sequences. Target cleavage by KmAgo depends on the formation of secondary structure indicating that KmAgo can be used for structural probing of RNA targets. Mismatches between the guide and target sequences greatly affect the efficiency and precision of target cleavage, depending on the mismatch position and the nature of the reacting nucleic acid. These properties of KmAgo open the way for its use for highly specific nucleic acid detection and cleavage.
]]></description>
<dc:creator>Kropocheva, E.</dc:creator>
<dc:creator>Kuzmenko, A.</dc:creator>
<dc:creator>Aravin, A.</dc:creator>
<dc:creator>Esyunina, D.</dc:creator>
<dc:creator>Kulbachiskiy, A.</dc:creator>
<dc:date>2021-02-03</dc:date>
<dc:identifier>doi:10.1101/2021.02.03.429301</dc:identifier>
<dc:title><![CDATA[A programmable pAgo nuclease with universal guide and target specificity from the mesophilic bacterium Kurthia massiliensis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-02-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.02.10.430659v1?rss=1">
<title>
<![CDATA[
Synthetic multistability in mammalian cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.02.10.430659v1?rss=1</link>
<description><![CDATA[
In multicellular organisms, gene regulatory circuits generate thousands of molecularly distinct, mitotically heritable states, through the property of multistability. Designing synthetic multistable circuits would provide insight into natural cell fate control circuit architectures and allow engineering of multicellular programs that require interactions among cells in distinct states. Here we introduce MultiFate, a naturally-inspired, synthetic circuit that supports long-term, controllable, and expandable multistability in mammalian cells. MultiFate uses engineered zinc finger transcription factors that transcriptionally self-activate as homodimers and mutually inhibit one another through heterodimerization. Using model-based design, we engineered MultiFate circuits that generate up to seven states, each stable for at least 18 days. MultiFate permits controlled state-switching and modulation of state stability through external inputs, and can be easily expanded with additional transcription factors. Together, these results provide a foundation for engineering multicellular behaviors in mammalian cells.
]]></description>
<dc:creator>Zhu, R.</dc:creator>
<dc:creator>del Rio-Salgado, J. M.</dc:creator>
<dc:creator>Garcia-Ojalvo, J.</dc:creator>
<dc:creator>Elowitz, M.</dc:creator>
<dc:date>2021-02-11</dc:date>
<dc:identifier>doi:10.1101/2021.02.10.430659</dc:identifier>
<dc:title><![CDATA[Synthetic multistability in mammalian cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-02-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.02.12.427428v1?rss=1">
<title>
<![CDATA[
The making of cauliflowers: the story of unsuccessful flowers 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.02.12.427428v1?rss=1</link>
<description><![CDATA[
The arrangement of plant organs, called phyllotaxis, produce remarkable spiral or whorled patterns. Cauliflowers present a unique phyllotaxis with a multitude of spirals over a wide range of scales. How such a self-similar fractal organization emerges from developmental mechanisms has remained elusive. Combining experimental assays with modeling, we found that cauliflowers arise due to the hysteresis of the bistable floral network that generates inflorescences imprinted by a transient floral state. We further show how additional mutations affecting meristem growth dynamics can induce the production of conical phyllotactic structures reminiscent of the conspicuous fractal Romanesco shape. This study reveals how the spectacular morphological modification of the inflorescences in cauliflower and Romanesco shape arises from the hysteresis of the genetic programs controlling inflorescence development.

One Sentence SummaryThe molecular making of cauliflowers
]]></description>
<dc:creator>Azpeitia, E.</dc:creator>
<dc:creator>Tichtinsky, G.</dc:creator>
<dc:creator>Le Masson, M.</dc:creator>
<dc:creator>Serrano-Mislata, A.</dc:creator>
<dc:creator>Gregis, V.</dc:creator>
<dc:creator>Gimenez, C.</dc:creator>
<dc:creator>Prunet, N.</dc:creator>
<dc:creator>Lucas, J.</dc:creator>
<dc:creator>Farcot, E.</dc:creator>
<dc:creator>Kater, M.</dc:creator>
<dc:creator>Bradley, D.</dc:creator>
<dc:creator>Madueno, F.</dc:creator>
<dc:creator>Godin, C.</dc:creator>
<dc:creator>Parcy, F.</dc:creator>
<dc:date>2021-02-12</dc:date>
<dc:identifier>doi:10.1101/2021.02.12.427428</dc:identifier>
<dc:title><![CDATA[The making of cauliflowers: the story of unsuccessful flowers]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-02-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.02.14.431043v1?rss=1">
<title>
<![CDATA[
SARS-CoV-2 lineage B.1.526 emerging in the New York region detected by software utility created to query the spike mutational landscape 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.02.14.431043v1?rss=1</link>
<description><![CDATA[
Wide-scale SARS-CoV-2 genome sequencing is critical to tracking viral evolution during the ongoing pandemic. Variants first detected in the United Kingdom, South Africa, and Brazil have spread to multiple countries. We developed the software tool, Variant Database (VDB), for quickly examining the changing landscape of spike mutations. Using VDB, we detected an emerging lineage of SARS-CoV-2 in the New York region that shares mutations with previously reported variants. The most common sets of spike mutations in this lineage (now designated as B.1.526) are L5F, T95I, D253G, E484K or S477N, D614G, and A701V. This lineage was first sequenced in late November 2020 when it represented <1% of sequenced coronavirus genomes that were collected in New York City (NYC). By February 2021, genomes from this lineage accounted for ~32% of 3288 sequenced genomes from NYC specimens. Phylodynamic inference confirmed the rapid growth of the B.1.526 lineage in NYC, notably the sub-clade defined by the spike mutation E484K, which has outpaced the growth of other variants in NYC. Pseudovirus neutralization experiments demonstrated that B.1.526 spike mutations adversely affect the neutralization titer of convalescent and vaccinee plasma, indicating the public health importance of this lineage.
]]></description>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2021-02-15</dc:date>
<dc:identifier>doi:10.1101/2021.02.14.431043</dc:identifier>
<dc:title><![CDATA[SARS-CoV-2 lineage B.1.526 emerging in the New York region detected by software utility created to query the spike mutational landscape]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-02-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.02.16.431482v1?rss=1">
<title>
<![CDATA[
Affinity Requirements For Control Of Synaptic Targeting And Neuronal Cell Survival By Heterophilic IgSF Cell Adhesion Molecules 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.02.16.431482v1?rss=1</link>
<description><![CDATA[
Neurons in the developing brain express many different cell adhesion molecules (CAMs) on their surfaces, and CAM interactions are essential for the determination of synaptic connectivity patterns. CAM binding affinities can vary by more than 200-fold, but the significance of affinity differences among CAMs is unknown. Here we provide a systematic characterization of the in vivo consequences of altering CAM affinity. Interactions between DIP- and its binding partners Dpr6 and Dpr10 control synaptic targeting and cell survival for Drosophila optic lobe neurons. We generated mutations that change DIP-::Dpr10 binding affinity and introduced these into the endogenous loci. We show that cell survival and synaptic targeting have different affinity requirements, and that there is a threshold affinity required for targeting. Reducing affinity causes graded loss-of-function phenotypes, while increasing affinity rescues cells that would normally die. Affinity reduction can be compensated for by increasing gene copy number.
]]></description>
<dc:creator>Xu, S.</dc:creator>
<dc:creator>Sergeeva, A. P.</dc:creator>
<dc:creator>Katsamba, P. S.</dc:creator>
<dc:creator>Mannepalli, S.</dc:creator>
<dc:creator>Bahna, F.</dc:creator>
<dc:creator>Bimela, J.</dc:creator>
<dc:creator>Zipursky, L. S.</dc:creator>
<dc:creator>Shapiro, L.</dc:creator>
<dc:creator>Honig, B.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:date>2021-02-17</dc:date>
<dc:identifier>doi:10.1101/2021.02.16.431482</dc:identifier>
<dc:title><![CDATA[Affinity Requirements For Control Of Synaptic Targeting And Neuronal Cell Survival By Heterophilic IgSF Cell Adhesion Molecules]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-02-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.02.22.432372v1?rss=1">
<title>
<![CDATA[
Functional modules within a distributed neural network control feeding in a model medusa 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.02.22.432372v1?rss=1</link>
<description><![CDATA[
Jellyfish are free-swimming, radially symmetric organisms with complex behaviors that arise from coordinated interactions between distinct, autonomously functioning body parts. This behavioral complexity evolved without a corresponding cephalization of the nervous system. The systems-level neural mechanisms through which such decentralized control is achieved remain unclear. Here, we address this question using the jellyfish, Clytia, and present it as a new neuroscience model. We describe a coordinated, asymmetric behavior in which food is passed from the umbrellar margin to the central mouth via directed margin folding. Using newly developed transgenic jellyfish lines to ablate or image specific neuronal subpopulations, we find, unexpectedly, that margin folding reflects the local activation of neural subnetworks that tile the umbrella. Modeling suggests that this structured ensemble activity emerges from sparse, local connectivity rules. These findings reveal how an organismal behavior can emerge from local interactions between functional modules in the absence of a central brain.
]]></description>
<dc:creator>Weissbourd, B.</dc:creator>
<dc:creator>Momose, T.</dc:creator>
<dc:creator>Nair, A.</dc:creator>
<dc:creator>Kennedy, A.</dc:creator>
<dc:creator>Hunt, B.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:date>2021-02-23</dc:date>
<dc:identifier>doi:10.1101/2021.02.22.432372</dc:identifier>
<dc:title><![CDATA[Functional modules within a distributed neural network control feeding in a model medusa]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-02-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.02.24.432779v1?rss=1">
<title>
<![CDATA[
The stress-sensing domain of activated IRE1α forms helical filaments in narrow ER membrane tubes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.02.24.432779v1?rss=1</link>
<description><![CDATA[
The signaling network of the unfolded protein response (UPR) adjusts the protein folding capacity of the endoplasmic reticulum (ER) according to need. The most conserved UPR sensor, IRE1, spans the ER membrane and activates through oligomerization. IRE1 oligomers accumulate in dynamic foci. We determined the in-situ structure of IRE1 foci by cryogenic correlated light and electron microscopy (cryo-CLEM), combined with electron cryo-tomography (cryo-ET) and complementary immuno-electron microscopy. IRE1 oligomers localize to a network of narrow anastomosing ER tubes (diameter ~28 nm) with complex branching. The lumen of the tubes contains protein filaments, likely composed of linear arrays of IRE1 lumenal domain dimers, arranged in two intertwined, left-handed helices. Our findings define a previously unrecognized ER subdomain and suggest positive feedback in IRE1 signaling.
]]></description>
<dc:creator>Carter, S. D.</dc:creator>
<dc:creator>Tran, N.-H.</dc:creator>
<dc:creator>De Maziere, A.</dc:creator>
<dc:creator>Ashkenazi, A.</dc:creator>
<dc:creator>Klumperman, J.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Walter, P.</dc:creator>
<dc:date>2021-02-24</dc:date>
<dc:identifier>doi:10.1101/2021.02.24.432779</dc:identifier>
<dc:title><![CDATA[The stress-sensing domain of activated IRE1α forms helical filaments in narrow ER membrane tubes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-02-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.02.24.432792v1?rss=1">
<title>
<![CDATA[
In situ single-cell activities of microbial populations revealed by spatial transcriptomics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.02.24.432792v1?rss=1</link>
<description><![CDATA[
Microbial populations and communities are heterogeneous, yet capturing their diverse activities has proven challenging at the relevant spatiotemporal scales. Here we present par-seqFISH, a targeted transcriptome-imaging approach that records both gene-expression and spatial context within microscale assemblies at a single-cell and molecule resolution. We apply this approach to the opportunistic bacterial pathogen, Pseudomonas aeruginosa, analyzing [~]600,000 individuals across dozens of physiological conditions in planktonic and biofilm cultures. We explore the phenotypic landscape of this bacterium and identify metabolic and virulence related cell-states that emerge dynamically during growth. We chart the spatial context of biofilm-related processes including motility and kin-exclusion mechanisms and identify extensive and highly spatially-resolved metabolic heterogeneity. We find that distinct physiological states can co-exist within the same biofilm, just a few microns away, underscoring the importance of the microenvironment. Together, our results illustrate the complexity of microbial populations and present a new way of studying them at high-resolution.
]]></description>
<dc:creator>Dar, D.</dc:creator>
<dc:creator>Dar, N.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2021-02-25</dc:date>
<dc:identifier>doi:10.1101/2021.02.24.432792</dc:identifier>
<dc:title><![CDATA[In situ single-cell activities of microbial populations revealed by spatial transcriptomics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-02-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.02.25.432623v1?rss=1">
<title>
<![CDATA[
A functional logic for neurotransmitter co-release in the cholinergic forebrain pathway 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.02.25.432623v1?rss=1</link>
<description><![CDATA[
The forebrain cholinergic system has recently been shown to co-release both acetylcholine and GABA. We have discovered that such co-release by cholinergic inputs to the claustrum differentially affects neurons that project to cortical versus subcortical targets. The resulting changes in neuronal gain toggles network efficiency and discriminability of output between two different projection subcircuits. Our results provide a potential logic for neurotransmitter co-release in cholinergic systems.
]]></description>
<dc:creator>Nair, A.</dc:creator>
<dc:creator>Graf, M.</dc:creator>
<dc:creator>Teo, Y. Y.</dc:creator>
<dc:creator>Augustine, G. J.</dc:creator>
<dc:date>2021-02-25</dc:date>
<dc:identifier>doi:10.1101/2021.02.25.432623</dc:identifier>
<dc:title><![CDATA[A functional logic for neurotransmitter co-release in the cholinergic forebrain pathway]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-02-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.02.27.433214v1?rss=1">
<title>
<![CDATA[
Confirmation bias optimizes reward learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.02.27.433214v1?rss=1</link>
<description><![CDATA[
Confirmation bias--the tendency to overweight information that matches prior beliefs or choices--has been shown to manifest even in simple reinforcement learning. In line with recent work, we find that participants learned significantly more from choice-confirming outcomes in a reward-learning task. What is less clear is whether asymmetric learning rates somehow benefit the learner. Here, we combine data from human participants and artificial agents to examine how confirmation-biased learning might improve performance by counteracting decisional and environmental noise. We evaluate one potential mechanism for such noise reduction: visual attention--a demonstrated driver of both value-based choice and predictive learning. Surprisingly, visual attention showed the opposite pattern to confirmation bias, as participants were most likely to fixate on "missed opportunities", slightly dampening the effects of the confirmation bias we observed. Several million simulated experiments with artificial agents showed this bias to be a reward-maximizing strategy compared to several alternatives, but only if disconfirming feedback is not completely ignored--a condition that visual attention may help to enforce.
]]></description>
<dc:creator>Tarantola, T. O.</dc:creator>
<dc:creator>Folke, T.</dc:creator>
<dc:creator>Boldt, A.</dc:creator>
<dc:creator>Perez, O. D.</dc:creator>
<dc:creator>De Martino, B.</dc:creator>
<dc:date>2021-03-01</dc:date>
<dc:identifier>doi:10.1101/2021.02.27.433214</dc:identifier>
<dc:title><![CDATA[Confirmation bias optimizes reward learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.01.431313v1?rss=1">
<title>
<![CDATA[
Whole-cell segmentation of tissue images with human-level performance using large-scale data annotation and deep learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.01.431313v1?rss=1</link>
<description><![CDATA[
Understanding the spatial organization of tissues is of critical importance for both basic and translational research. While recent advances in tissue imaging are opening an exciting new window into the biology of human tissues, interpreting the data that they create is a significant computational challenge. Cell segmentation, the task of uniquely identifying each cell in an image, remains a substantial barrier for tissue imaging, as existing approaches are inaccurate or require a substantial amount of manual curation to yield useful results. Here, we addressed the problem of cell segmentation in tissue imaging data through large-scale data annotation and deep learning. We constructed TissueNet, an image dataset containing >1 million paired whole-cell and nuclear annotations for tissue images from nine organs and six imaging platforms. We created Mesmer, a deep learning-enabled segmentation algorithm trained on TissueNet that performs nuclear and whole-cell segmentation in tissue imaging data. We demonstrated that Mesmer has better speed and accuracy than previous methods, generalizes to the full diversity of tissue types and imaging platforms in TissueNet, and achieves human-level performance for whole-cell segmentation. Mesmer enabled the automated extraction of key cellular features, such as subcellular localization of protein signal, which was challenging with previous approaches. We further showed that Mesmer could be adapted to harness cell lineage information present in highly multiplexed datasets. We used this enhanced version to quantify cell morphology changes during human gestation. All underlying code and models are released with permissive licenses as a community resource.
]]></description>
<dc:creator>Greenwald, N. F.</dc:creator>
<dc:creator>Miller, G.</dc:creator>
<dc:creator>Moen, E.</dc:creator>
<dc:creator>Kong, A.</dc:creator>
<dc:creator>Kagel, A.</dc:creator>
<dc:creator>Fullaway, C. C.</dc:creator>
<dc:creator>McIntosh, B. J.</dc:creator>
<dc:creator>Leow, K.</dc:creator>
<dc:creator>Schwartz, M. S.</dc:creator>
<dc:creator>Dougherty, T.</dc:creator>
<dc:creator>Pavelchek, C.</dc:creator>
<dc:creator>Cui, S.</dc:creator>
<dc:creator>Camplisson, I.</dc:creator>
<dc:creator>Bar-Tal, O.</dc:creator>
<dc:creator>Singh, J.</dc:creator>
<dc:creator>Fong, M.</dc:creator>
<dc:creator>Chaudhry, G.</dc:creator>
<dc:creator>Abraham, Z.</dc:creator>
<dc:creator>Moseley, J.</dc:creator>
<dc:creator>Warshawsky, S.</dc:creator>
<dc:creator>Soon, E.</dc:creator>
<dc:creator>Greenbaum, S.</dc:creator>
<dc:creator>Risom, T.</dc:creator>
<dc:creator>Hollmann, T.</dc:creator>
<dc:creator>Keren, L.</dc:creator>
<dc:creator>Graf, W.</dc:creator>
<dc:creator>Angelo, M.</dc:creator>
<dc:creator>Van Valen, D.</dc:creator>
<dc:date>2021-03-02</dc:date>
<dc:identifier>doi:10.1101/2021.03.01.431313</dc:identifier>
<dc:title><![CDATA[Whole-cell segmentation of tissue images with human-level performance using large-scale data annotation and deep learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.01.431439v1?rss=1">
<title>
<![CDATA[
Placental uptake and metabolism as determinants of pregnancy vitamin D status 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.01.431439v1?rss=1</link>
<description><![CDATA[
Pregnancy 25-hydroxyvitamin D (25(OH)D) concentrations are associated with maternal and fetal health outcomes. Using physiological human placental perfusion and villous explants, we investigate the role of the placenta in regulating the relationships between maternal 25(OH)D and fetal physiology. We demonstrate active placental uptake of 25(OH)D3 by endocytosis, placental metabolism of 25(OH)D3 into 24,25-dihydroxyvitamin D3 and active 1,25-dihydroxyvitamin D [1,25(OH)2D3], with subsequent release of these metabolites into both the maternal and fetal circulations. Active placental transport of 25(OH)D3 and synthesis of 1,25(OH)2D3 demonstrate that fetal supply is dependent on placental function rather than simply the availability of maternal 25(OH)D3. We demonstrate that 25(OH)D3 exposure induces rapid effects on the placental transcriptome and proteome. These map to multiple pathways central to placental function and thereby fetal development, independent of vitamin D transfer. Our data suggest that the underlying epigenetic landscape helps dictate the transcriptional response to vitamin D treatment. This is the first quantitative study demonstrating vitamin D transfer and metabolism by the human placenta, with widespread effects on the placenta itself. These data demonstrate a complex interplay between vitamin D and the placenta and will inform future interventions using vitamin D to support fetal development and maternal adaptations to pregnancy.
]]></description>
<dc:creator>Ashley, B.</dc:creator>
<dc:creator>Simner, C.</dc:creator>
<dc:creator>Manousopoulou, A.</dc:creator>
<dc:creator>Jenkinson, C.</dc:creator>
<dc:creator>Hey, F.</dc:creator>
<dc:creator>Frost, J. M.</dc:creator>
<dc:creator>Rezwan, F. I.</dc:creator>
<dc:creator>White, C. H.</dc:creator>
<dc:creator>Lofthouse, E. M.</dc:creator>
<dc:creator>Hyde, E.</dc:creator>
<dc:creator>Cooke, L.</dc:creator>
<dc:creator>Barton, S.</dc:creator>
<dc:creator>Mahon, P.</dc:creator>
<dc:creator>Curtis, E. M.</dc:creator>
<dc:creator>Moon, R. J.</dc:creator>
<dc:creator>Crozier, S. R.</dc:creator>
<dc:creator>Inskip, H. M.</dc:creator>
<dc:creator>Godfrey, K. M.</dc:creator>
<dc:creator>Holloway, J. W.</dc:creator>
<dc:creator>Cooper, C.</dc:creator>
<dc:creator>Jones, K. S.</dc:creator>
<dc:creator>Lewis, R. M.</dc:creator>
<dc:creator>Hewison, M.</dc:creator>
<dc:creator>Garbis, S. D.</dc:creator>
<dc:creator>Branco, M. R.</dc:creator>
<dc:creator>Harvey, N. C.</dc:creator>
<dc:creator>Cleal, J. K.</dc:creator>
<dc:date>2021-03-01</dc:date>
<dc:identifier>doi:10.1101/2021.03.01.431439</dc:identifier>
<dc:title><![CDATA[Placental uptake and metabolism as determinants of pregnancy vitamin D status]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.02.433560v1?rss=1">
<title>
<![CDATA[
Modelling the impact of decidual senescence on embryo implantation in human endometrial assembloids 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.02.433560v1?rss=1</link>
<description><![CDATA[
Decidual remodelling of midluteal endometrium leads to a short implantation window after which the uterine mucosa either breaks down or is transformed into a robust matrix that accommodates the placenta throughout pregnancy. To gain insights into the underlying mechanisms, we established and characterised endometrial assembloids, consisting of gland organoids and primary stromal cells. Single-cell transcriptomics revealed that decidualized assembloids closely resemble midluteal endometrium, harbouring differentiated and senescent subpopulations in both glands and stroma. We show that acute senescence in glandular epithelium drives secretion of multiple canonical implantation factors, whereas in the stroma it calibrates the emergence of anti-inflammatory decidual cells and pro-inflammatory senescent decidual cells. Pharmacological inhibition of stress responses in pre-decidual cells accelerated decidualization by inhibiting senescence and mesenchymal-epithelial transition, processes involved in endometrial breakdown and regeneration, respectively. Accelerated decidualization resulted in entrapment of co-cultured human blastocysts in a largely static decidual matrix. By contrast, the presence of senescent decidual cells created a dynamic implantation environment, enabling embryo expansion and attachment, although their persistence led to gradual disintegration of assembloids. Our findings demonstrate that senescence controls endometrial fate decisions at implantation and highlight how endometrial assembloids may accelerate the discovery of new treatments to prevent reproductive failure.
]]></description>
<dc:creator>Rawlings, T. M.</dc:creator>
<dc:creator>Makwana, K.</dc:creator>
<dc:creator>Taylor, D. M.</dc:creator>
<dc:creator>Mole, M. A.</dc:creator>
<dc:creator>Fishwick, K. J.</dc:creator>
<dc:creator>Tryfonos, M.</dc:creator>
<dc:creator>Odendaal, J.</dc:creator>
<dc:creator>Hawkes, A.</dc:creator>
<dc:creator>Zernicka-Goetz, M.</dc:creator>
<dc:creator>Hartshorne, G.</dc:creator>
<dc:creator>Brosens, J.</dc:creator>
<dc:creator>Lucas, E. S.</dc:creator>
<dc:date>2021-03-02</dc:date>
<dc:identifier>doi:10.1101/2021.03.02.433560</dc:identifier>
<dc:title><![CDATA[Modelling the impact of decidual senescence on embryo implantation in human endometrial assembloids]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.05.434127v1?rss=1">
<title>
<![CDATA[
The Mycobacterium tuberculosis transposon sequencing database (MtbTnDB): a large-scale guide to genetic conditional essentiality 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.05.434127v1?rss=1</link>
<description><![CDATA[
Characterizing genetic essentiality across various conditions is fundamental for understanding gene function. Transposon sequencing (TnSeq) is a powerful technique to generate genome-wide essentiality profiles in bacteria and has been extensively applied to Mycobacterium tuberculosis (Mtb). Dozens of TnSeq screens have yielded valuable insights into the biology of Mtb in vitro, inside macrophages, and in model host organisms. Despite their value, these Mtb TnSeq profiles have not been standardized or collated into a single, easily searchable database. This results in significant challenges when attempting to query and compare these resources, limiting our ability to obtain a comprehensive and consistent understanding of genetic conditional essentiality in Mtb. We address this problem by building a central repository of publicly available Mtb TnSeq screens, the Mtb transposon sequencing database (MtbTnDB). The MtbTnDB is a living resource that encompasses to date {approx}150 standardized TnSeq screens, enabling open access to data, visualizations, and functional predictions through an interactive web app (www.mtbtndb.app). We conduct several statistical analyses on the complete database, such as demonstrating that (i) genes in the same genomic neighborhood have similar TnSeq profiles, and (ii) clusters of genes with similar TnSeq profiles are enriched for genes from similar functional categories. We further analyze the performance of machine learning models trained on TnSeq profiles to predict functional annotation of orphan genes in Mtb. By facilitating the comparison of TnSeq screens across conditions, the MtbTnDB will accelerate the exploration of conditional genetic essentiality, provide insights into the functional organization of Mtb genes, and help predict gene function in this important human pathogen.
]]></description>
<dc:creator>Jinich, A.</dc:creator>
<dc:creator>Zaveri, A.</dc:creator>
<dc:creator>DeJesus, M. A.</dc:creator>
<dc:creator>Flores-Bautista, E.</dc:creator>
<dc:creator>Smith, C. M.</dc:creator>
<dc:creator>Sassetti, C. M.</dc:creator>
<dc:creator>Rock, J. M.</dc:creator>
<dc:creator>Ehrt, S.</dc:creator>
<dc:creator>Schnappinger, D.</dc:creator>
<dc:creator>Ioerger, T. R.</dc:creator>
<dc:creator>Rhee, K. Y.</dc:creator>
<dc:date>2021-03-06</dc:date>
<dc:identifier>doi:10.1101/2021.03.05.434127</dc:identifier>
<dc:title><![CDATA[The Mycobacterium tuberculosis transposon sequencing database (MtbTnDB): a large-scale guide to genetic conditional essentiality]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.07.434227v1?rss=1">
<title>
<![CDATA[
Development of potency, breadth and resilience to viral escape mutations in SARS-CoV-2 neutralizing antibodies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.07.434227v1?rss=1</link>
<description><![CDATA[
Antibodies elicited in response to infection undergo somatic mutation in germinal centers that can result in higher affinity for the cognate antigen. To determine the effects of somatic mutation on the properties of SARS-CoV-2 spike receptor-binding domain (RBD)-specific antibodies, we analyzed six independent antibody lineages. As well as increased neutralization potency, antibody evolution changed pathways for acquisition of resistance and, in some cases, restricted the range of neutralization escape options. For some antibodies, maturation apparently imposed a requirement for multiple spike mutations to enable escape. For certain antibody lineages, maturation enabled neutralization of circulating SARS-CoV-2 variants of concern and heterologous sarbecoviruses. Antibody-antigen structures revealed that these properties resulted from substitutions that allowed additional variability at the interface with the RBD. These findings suggest that increasing antibody diversity through prolonged or repeated antigen exposure may improve protection against diversifying SARS-CoV-2 populations, and perhaps against other pandemic threat coronaviruses.
]]></description>
<dc:creator>Muecksch, F.</dc:creator>
<dc:creator>Weisblum, Y.</dc:creator>
<dc:creator>Barnes, C.</dc:creator>
<dc:creator>Schmidt, F.</dc:creator>
<dc:creator>Schaefer-Babajew, D.</dc:creator>
<dc:creator>Lorenzi, J.</dc:creator>
<dc:creator>Flyak, A.</dc:creator>
<dc:creator>DeLaitsch, A.</dc:creator>
<dc:creator>Huey-Tubman, K.</dc:creator>
<dc:creator>Hou, S.</dc:creator>
<dc:creator>Schiffer, C.</dc:creator>
<dc:creator>Gaebler, C.</dc:creator>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>Da Silva, J.</dc:creator>
<dc:creator>Poston, D.</dc:creator>
<dc:creator>Finkin, S.</dc:creator>
<dc:creator>Cho, A.</dc:creator>
<dc:creator>Cipolla, M.</dc:creator>
<dc:creator>Oliveira, T.</dc:creator>
<dc:creator>Millard, K.</dc:creator>
<dc:creator>Ramos, V.</dc:creator>
<dc:creator>Gazumyan, A.</dc:creator>
<dc:creator>Rutkowska, M.</dc:creator>
<dc:creator>Caskey, M.</dc:creator>
<dc:creator>Nussenzweig, M.</dc:creator>
<dc:creator>Bjorkman, P.</dc:creator>
<dc:creator>Hatziioannou, T.</dc:creator>
<dc:creator>Bieniasz, P.</dc:creator>
<dc:date>2021-03-08</dc:date>
<dc:identifier>doi:10.1101/2021.03.07.434227</dc:identifier>
<dc:title><![CDATA[Development of potency, breadth and resilience to viral escape mutations in SARS-CoV-2 neutralizing antibodies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.10.434868v1?rss=1">
<title>
<![CDATA[
Droplet-based single cell RNA sequencing of bacteria identifies known and previously unseen cellular states 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.10.434868v1?rss=1</link>
<description><![CDATA[
Clonal bacterial populations rely on transcriptional variation to differentiate into specialized cell states that increase the communitys fitness. Such heterogeneous gene expression is implicated in many fundamental microbial processes including sporulation, cell communication, detoxification, substrate utilization, competence, biofilm formation, motility, pathogenicity, and antibiotic resistance1. To identify these specialized cell states and determine the processes by which they develop, we need to study isogenic bacterial populations at the single cell level2,3. Here, we develop a method that uses DNA probes and leverages an existing commercial microfluidic platform (10X Chromium) to conduct bacterial single cell RNA sequencing. We sequenced the transcriptome of over 15,000 individual bacterial cells, detecting on average 365 transcripts mapping to 265 genes per cell in B. subtilis and 329 transcripts mapping to 149 genes per cell in E. coli. Our findings correctly identify known cell states and uncover previously unreported cell states. Interestingly, we find that some metabolic pathways segregate into distinct subpopulations across different bacteria and growth conditions, suggesting that some cellular processes may be more prone to differentiation than others. Our high throughput, highly resolved single cell transcriptomic platform can be broadly used for understanding heterogeneity in microbial populations.
]]></description>
<dc:creator>McNulty, R. A.</dc:creator>
<dc:creator>Sritharan, D.</dc:creator>
<dc:creator>Liu, S.</dc:creator>
<dc:creator>Hormoz, S.</dc:creator>
<dc:creator>Rosenthal, A. Z.</dc:creator>
<dc:date>2021-03-10</dc:date>
<dc:identifier>doi:10.1101/2021.03.10.434868</dc:identifier>
<dc:title><![CDATA[Droplet-based single cell RNA sequencing of bacteria identifies known and previously unseen cellular states]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.11.435011v1?rss=1">
<title>
<![CDATA[
Coordination of -1 Programmed Ribosomal Frameshifting by Transcript and Nascent Chain Features Revealed by Deep Mutational Scanning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.11.435011v1?rss=1</link>
<description><![CDATA[
Programmed ribosomal frameshifting (PRF) is a translational recoding mechanism that enables the synthesis of multiple polypeptides from a single transcript. In the alphavirus structural polyprotein, -1PRF is coordinated by a "slippery" sequence in the transcript, an RNA stem-loop, and a conformational transition in the nascent polypeptide chain. To characterize each of these effectors, we measured the effects of 4,530 mutations on -1PRF by deep mutational scanning. While most mutations within the slip-site and stem-loop disrupt -1PRF, mutagenic effects upstream of the slip-site are far more variable. Molecular dynamics simulations of polyprotein biogenesis suggest many of these mutations alter stimulatory forces on the nascent chain through their effects on translocon-mediated cotranslational folding. Finally, we provide evidence suggesting the coupling between cotranslational folding and -1PRF depends on the translation kinetics upstream of the slip-site. These findings demonstrate how -1PRF is coordinated by features within both the transcript and nascent chain.
]]></description>
<dc:creator>Carmody, P. J.</dc:creator>
<dc:creator>Zimmer, M. H.</dc:creator>
<dc:creator>Kuntz, C. P.</dc:creator>
<dc:creator>Harrington, H. R.</dc:creator>
<dc:creator>Duckworth, K. E.</dc:creator>
<dc:creator>Penn, W. D.</dc:creator>
<dc:creator>Mukhopahyay, S.</dc:creator>
<dc:creator>Miller, T. F.</dc:creator>
<dc:creator>Schlebach, J. P.</dc:creator>
<dc:date>2021-03-11</dc:date>
<dc:identifier>doi:10.1101/2021.03.11.435011</dc:identifier>
<dc:title><![CDATA[Coordination of -1 Programmed Ribosomal Frameshifting by Transcript and Nascent Chain Features Revealed by Deep Mutational Scanning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.12.435035v1?rss=1">
<title>
<![CDATA[
Learning accurate path integration in a ring attractor model of the head direction system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.12.435035v1?rss=1</link>
<description><![CDATA[
Ring attractor models for angular path integration have recently received strong experimental support. To function as integrators, head-direction (HD) circuits require precisely tuned connectivity, but it is currently unknown how such tuning could be achieved. Here, we propose a network model in which a local, biologically plausible learning rule adjusts synaptic efficacies during development, guided by supervisory allothetic cues. Applied to the Drosophila HD system, the model learns to path-integrate accurately and develops a connectivity strikingly similar to the one reported in experiments. The mature network is a quasi-continuous attractor and reproduces key experiments in which optogenetic stimulation controls the internal representation of heading, and where the network remaps to integrate with different gains. Our model predicts that path integration requires supervised learning during a developmental phase. The model setting is general and also applies to architectures that lack the physical topography of a ring, like the mammalian HD system.
]]></description>
<dc:creator>Vafidis, P.</dc:creator>
<dc:creator>Owald, D.</dc:creator>
<dc:creator>D'Albis, T.</dc:creator>
<dc:creator>Kempter, R.</dc:creator>
<dc:date>2021-03-12</dc:date>
<dc:identifier>doi:10.1101/2021.03.12.435035</dc:identifier>
<dc:title><![CDATA[Learning accurate path integration in a ring attractor model of the head direction system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.12.435175v1?rss=1">
<title>
<![CDATA[
Reconstructing human early embryogenesis in vitro with pluripotent stem cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.12.435175v1?rss=1</link>
<description><![CDATA[
Understanding human development is of fundamental biological and clinical importance. Yet despite its significance, insights into early developmental events in humans still remain largely unknown. While recent advances show that stem cells can mimic embryogenesis1-9 to unravel hidden developmental mechanisms, a stem cell-based model of early human embryogenesis is lacking. Here, we use human extended pluripotent stem cells10to reconstitute early human development in 3-dimensions and recapitulate early embryo-like events. We first perform a systematic characterisation to reveal unique signalling requirements for building the human pre-implantation blastocyst. Further, we show that these in vitro stem cell-derived blastocyst-like structures are able to undertake spatiotemporal self-organisation to mimic peri-implantation remodelling in which a polarised rosette opens up the amniotic cavity within a developing disc. The hallmarks of human early development displayed by this stem cell-based in vitro model mimics features of embryonic day 3 to day 9/10 of natural development. Thus, this platform represents a tractable model system to contribute to the basic understanding of cellular and molecular mechanisms governing early embryonic events in humans and to provide valuable insights into the design of differentiation protocols for human stem cells in clinical applications.
]]></description>
<dc:creator>Zernicka-Goetz, M.</dc:creator>
<dc:creator>Sozen, B.</dc:creator>
<dc:creator>Jorgensen, V.</dc:creator>
<dc:creator>Cui, T.</dc:creator>
<dc:creator>Zhu, M.</dc:creator>
<dc:date>2021-03-12</dc:date>
<dc:identifier>doi:10.1101/2021.03.12.435175</dc:identifier>
<dc:title><![CDATA[Reconstructing human early embryogenesis in vitro with pluripotent stem cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.17.435888v1?rss=1">
<title>
<![CDATA[
Nanoparticle Cellular Internalization is Not Required for RNA Delivery to Mature Plant Leaves 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.17.435888v1?rss=1</link>
<description><![CDATA[
Rapidly growing interest in nanoparticle-mediated delivery of DNA and RNA to plants requires a better understanding of how nanoparticles and their cargoes translocate in plant tissues and into plant cells. However, little is known about how the size and shape of nanoparticles influences transport in plants and use of their cargoes, limiting development and deployment of nanotechnology in plant systems. Here, we employ non-biolistically delivered DNA-modified gold nanoparticles (AuNP) spanning various sizes (5 - 20 nm) and shapes (spheres and rods) to systematically investigate their transport following infiltration into Nicotiana benthamiana (Nb) leaves. Generally, smaller AuNPs demonstrate more rapid, higher, and longer-lasting levels of association with plant cell walls compared to larger AuNPs. We observe internalization of rod-shaped but not spherical AuNPs into plant cells, yet surprisingly, 10 nm spherical AuNP functionalized with small-interfering RNA (siRNA) are most efficient at siRNA delivery and inducing gene silencing in mature plant leaves. These results indicate the importance of nanoparticle size in efficient biomolecule delivery, and, counterintuitively, demonstrate that efficient cargo delivery is possible and potentially optimal in the absence of nanoparticle cellular internalization. Our results highlight nanoparticle features of importance for transport within plant tissues, providing a mechanistic overview of how nanoparticles can be designed to achieve efficacious bio-cargo delivery for future developments in plant nanobiotechnology.
]]></description>
<dc:creator>Zhang, H.</dc:creator>
<dc:creator>Goh, N. S.</dc:creator>
<dc:creator>Wang, J.</dc:creator>
<dc:creator>Demirer, G. S.</dc:creator>
<dc:creator>Butrus, S.</dc:creator>
<dc:creator>Park, S.-J.</dc:creator>
<dc:creator>Landry, M. P.</dc:creator>
<dc:date>2021-03-19</dc:date>
<dc:identifier>doi:10.1101/2021.03.17.435888</dc:identifier>
<dc:title><![CDATA[Nanoparticle Cellular Internalization is Not Required for RNA Delivery to Mature Plant Leaves]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.17.435890v1?rss=1">
<title>
<![CDATA[
Gold nanocluster mediated delivery of siRNA to intact plant cells for efficient gene knockdown 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.17.435890v1?rss=1</link>
<description><![CDATA[
RNA interference (RNAi), which involves the delivery of small interfering RNA molecules (siRNA), has been used to validate target genes in plants, to understand and control cellular metabolic pathways, and as a  green alternative for crop pest tolerance. Conventional siRNA delivery methods such as viruses and Agrobacterium-mediated delivery exhibit limitations in host plant species range and their use can result in uncontrolled DNA integration into the plant host genome. Here, we synthesize polyethyleneimine functionalized gold nanoclusters (PEI-AuNCs) to mediate siRNA delivery into intact plant cells and show these constructs enable efficient gene knockdown. We demonstrate that functionalized AuNCs protect siRNA from RNase degradation and are small enough (~2 nm) to bypass the plant cell wall which exhibits a size exclusion limit of 5-20 nm. These AuNCs in turn enable up to 76.5 {+/-} 5.9% GFP mRNA knockdown efficiency with no cellular toxicity. Our data suggest this simple and biocompatible platform for passive delivery of siRNA into intact plant cells could have broad applications in plant biotechnology.
]]></description>
<dc:creator>Zhang, H.</dc:creator>
<dc:creator>Cao, Y.</dc:creator>
<dc:creator>Xu, D.</dc:creator>
<dc:creator>Goh, N. S.</dc:creator>
<dc:creator>Demirer, G. S.</dc:creator>
<dc:creator>Landry, M. P.</dc:creator>
<dc:creator>Yang, P.</dc:creator>
<dc:date>2021-03-17</dc:date>
<dc:identifier>doi:10.1101/2021.03.17.435890</dc:identifier>
<dc:title><![CDATA[Gold nanocluster mediated delivery of siRNA to intact plant cells for efficient gene knockdown]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.22.434850v1?rss=1">
<title>
<![CDATA[
A novel approach to comparative RNA-Seq does not support a conserved set of genes underlying animal regeneration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.22.434850v1?rss=1</link>
<description><![CDATA[
Molecular studies of animal regeneration typically focus on conserved genes and signaling pathways that underlie morphogenesis. To date, a holistic analysis of gene expression across animals has not been attempted, as it presents a suite of problems related to differences in experimental design and gene homology. By combining orthology analysis with a novel statistical method for testing gene enrichment across large datasets, we are able to test whether biological processes across organisms share transcriptional regulation. We applied this method to six publicly available RNA-seq datasets from diverse examples of animal regeneration. We recovered 160 conserved orthologous gene clusters, which are enriched in structural genes as opposed to those regulating morphogenesis. A breakdown of gene presence/absence provides only limited support for the conservation of pathways typically implicated in regeneration, such as Wnt signaling and cell pluripotency. Specifically, these pathways are only conserved if we allow gene paralogs to be interchangeable through evolution. Overall, our analysis does not support the hypothesis that a shared set of ancestral genes underlie regeneration mechanisms in animals. The methods described in this paper will be broadly applicable for studying the genetic underpinnings of traits across distantly related organisms.
]]></description>
<dc:creator>Sierra, N.</dc:creator>
<dc:creator>Olsman, N.</dc:creator>
<dc:creator>Yi, L.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Goentoro, L.</dc:creator>
<dc:creator>Gold, D. A.</dc:creator>
<dc:date>2021-03-23</dc:date>
<dc:identifier>doi:10.1101/2021.03.22.434850</dc:identifier>
<dc:title><![CDATA[A novel approach to comparative RNA-Seq does not support a conserved set of genes underlying animal regeneration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.22.436337v1?rss=1">
<title>
<![CDATA[
Live imaging of SARS-CoV-2 infection in mice reveals neutralizing antibodies require Fc function for optimal efficacy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.22.436337v1?rss=1</link>
<description><![CDATA[
Neutralizing antibodies (NAbs) are effective in treating COVID-19 but the mechanism of immune protection is not fully understood. Here, we applied live bioluminescence imaging (BLI) to monitor the real-time effects of NAb treatment in prophylaxis and therapy of K18-hACE2 mice intranasally infected with SARS-CoV-2-nanoluciferase. We could visualize virus spread sequentially from the nasal cavity to the lungs and thereafter systemically to various organs including the brain, which culminated in death. Highly potent NAbs from a COVID-19 convalescent subject prevented, and also effectively resolved, established infection when administered within three days. In addition to direct Fab-mediated neutralization, Fc effector interactions of NAbs with monocytes, neutrophils and natural killer cells were required to effectively dampen inflammatory responses and limit immunopathology. Our study highlights that both Fab and Fc effector functions of NAbs are essential for optimal in vivo efficacy against SARS-CoV-2.
]]></description>
<dc:creator>Ullah, I.</dc:creator>
<dc:creator>Prevost, J.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Stone, H.</dc:creator>
<dc:creator>Lu, M.</dc:creator>
<dc:creator>Anand, S. P.</dc:creator>
<dc:creator>Beaudoin-Bussieres, G.</dc:creator>
<dc:creator>Benlarbi, M.</dc:creator>
<dc:creator>Ding, S.</dc:creator>
<dc:creator>Gasser, R.</dc:creator>
<dc:creator>Fink, C.</dc:creator>
<dc:creator>Chen, Y.</dc:creator>
<dc:creator>Tauzin, A.</dc:creator>
<dc:creator>Goyette, G.</dc:creator>
<dc:creator>Bourassa, C.</dc:creator>
<dc:creator>Medjahed, H.</dc:creator>
<dc:creator>Mack, M.</dc:creator>
<dc:creator>Chung, K.</dc:creator>
<dc:creator>Wilen, C. B.</dc:creator>
<dc:creator>Dekaban, G. A.</dc:creator>
<dc:creator>Dikeakos, J. D.</dc:creator>
<dc:creator>Bruce, E. A.</dc:creator>
<dc:creator>Kaufmann, D. E.</dc:creator>
<dc:creator>Stamatatos, L.</dc:creator>
<dc:creator>McGuire, A.</dc:creator>
<dc:creator>Richard, J.</dc:creator>
<dc:creator>Pazgier, M.</dc:creator>
<dc:creator>Bjorkman, P.</dc:creator>
<dc:creator>Mothes, W.</dc:creator>
<dc:creator>Finzi, A.</dc:creator>
<dc:creator>Kumar, P.</dc:creator>
<dc:creator>Uchil, P. D.</dc:creator>
<dc:date>2021-03-22</dc:date>
<dc:identifier>doi:10.1101/2021.03.22.436337</dc:identifier>
<dc:title><![CDATA[Live imaging of SARS-CoV-2 infection in mice reveals neutralizing antibodies require Fc function for optimal efficacy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.24.436847v1?rss=1">
<title>
<![CDATA[
Analytical solutions of the chemical master equation with bursty production and isomerization reactions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.24.436847v1?rss=1</link>
<description><![CDATA[
Splicing cascades that alter gene products post-transcriptionally also affect expression dynamics. We study a class of processes and associated distributions that emerge from a bursty promoter model coupled to a path graph of downstream mRNA splicing, and more generally examine the behavior of finite-activity jump drivers coupled to a directed acyclic graph of splicing with one or more roots. These solutions provide full time-dependent joint distributions for an arbitrary number of species, offering qualitative and quantitative insights about how splicing can regulate expression dynamics. Finally, we derive a set of quantitative constraints on the minimum complexity necessary to reproduce gene co-expression patterns using synchronized burst models. We validate these findings by analyzing long-read sequencing data, where we find evidence of expression patterns largely consistent with these constraints.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2021-03-24</dc:date>
<dc:identifier>doi:10.1101/2021.03.24.436847</dc:identifier>
<dc:title><![CDATA[Analytical solutions of the chemical master equation with bursty production and isomerization reactions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.25.434639v1?rss=1">
<title>
<![CDATA[
Acoustic Remote Control of Bacterial Immunotherapy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.25.434639v1?rss=1</link>
<description><![CDATA[
Rapid advances in synthetic biology are driving the development of genetically engineered microbes as therapeutic agents for a multitude of human diseases, including cancer. In particular, the immunosuppressive microenvironment of solid tumors creates a favorable niche for systemically administered bacteria to engraft in the tumor and release therapeutic payloads. However, such payloads can be harmful if released in healthy tissues where the bacteria also engraft in smaller numbers. To address this limitation, we engineer therapeutic bacteria to be controlled by focused ultrasound, a form of energy that can be applied noninvasively to specific anatomical sites such as solid tumors. This control is provided by a temperature-actuated genetic state switch that produces lasting therapeutic output in response to briefly applied focused ultrasound hyperthermia. Using a combination of rational design and high-throughput screening we optimized the switching circuits of engineered cells and connected their activity to the release of immune checkpoint inhibitors. In a clinically relevant cancer model, ultrasound-activated therapeutic microbes successfully turned on in situ and induced a marked suppression of tumor growth. This technology provides a critical tool for the spatiotemporal targeting of potent bacterial therapeutics in a variety of biological and clinical scenarios.
]]></description>
<dc:creator>Abedi, M.</dc:creator>
<dc:creator>Yao, M.</dc:creator>
<dc:creator>Mittelstein, D. R.</dc:creator>
<dc:creator>Bar-Zion, A.</dc:creator>
<dc:creator>Swift, M.</dc:creator>
<dc:creator>Lee-Gosselin, A.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2021-03-25</dc:date>
<dc:identifier>doi:10.1101/2021.03.25.434639</dc:identifier>
<dc:title><![CDATA[Acoustic Remote Control of Bacterial Immunotherapy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.26.436869v1?rss=1">
<title>
<![CDATA[
Tracking the rates and mechanisms of canopy damage and recovery following Hurricane Maria using multitemporal lidar data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.26.436869v1?rss=1</link>
<description><![CDATA[
Hurricane Maria (Category 4) snapped and uprooted canopy trees, removed large branches, and defoliated vegetation across Puerto Rico. The magnitude of forest damages and the rates and mechanisms of forest recovery following Maria provide important benchmarks for understanding the ecology of extreme events. We used airborne lidar data acquired before (2017) and after Maria (2018, 2020) to quantify landscape-scale changes in forest structure along a 439-ha elevational gradient (100 to 800 m) in the Luquillo Experimental Forest. Damages from Maria were widespread, with 73% of the study area losing [&ge;]1 m in canopy height (mean = -7.1 m). Taller forests at lower elevations suffered more damage than shorter forests above 600 m. Yet only 13% of the study area had canopy heights [&le;]2 m in 2018, a typical threshold for forest gaps, highlighting the importance of damaged trees and advanced regeneration on post-storm forest structure. Heterogeneous patterns of regrowth and recruitment yielded shorter and more open forests by 2020. Nearly 45% of forests experienced initial height loss (<-1 m, 2017-2018) followed by rapid height gain (>1 m, 2018-2020), whereas 21.6% of forests with initial height losses showed little or no height gain, and 17.8% of forests exhibited no structural changes >|1| m in either period. Canopy layers <10 m accounted for most increases in canopy height and fractional cover between 2018-2020, with gains split evenly between height growth and lateral crown expansion by surviving individuals. These findings benchmark rates of gap formation, crown expansion, and canopy closure following hurricane damage.

MANUSCRIPT HIGHLIGHTSO_LIHurricane Maria gave forests a haircut by toppling trees and shearing branches.
C_LIO_LIRegrowth after Maria was patchy, with equal areas of height gain and no change.
C_LIO_LI3-D measures of forest recovery after hurricanes can improve ecosystem models.
C_LI
]]></description>
<dc:creator>Leitold, V.</dc:creator>
<dc:creator>Morton, D. C.</dc:creator>
<dc:creator>Martinuzzi, S.</dc:creator>
<dc:creator>Paynter, I.</dc:creator>
<dc:creator>Uriarte, M.</dc:creator>
<dc:creator>Keller, M.</dc:creator>
<dc:creator>Ferraz, A.</dc:creator>
<dc:creator>Cook, B. D.</dc:creator>
<dc:creator>Corp, L. A.</dc:creator>
<dc:creator>Gonzalez, G.</dc:creator>
<dc:date>2021-03-28</dc:date>
<dc:identifier>doi:10.1101/2021.03.26.436869</dc:identifier>
<dc:title><![CDATA[Tracking the rates and mechanisms of canopy damage and recovery following Hurricane Maria using multitemporal lidar data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.28.437412v1?rss=1">
<title>
<![CDATA[
Paraburkholderia edwinii protects Aspergillus sp. from phenazines by acting as a toxin sponge 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.28.437412v1?rss=1</link>
<description><![CDATA[
Many environmentally and clinically important fungi are sensitive to toxic, bacterially-produced, redox-active molecules called phenazines. Despite being vulnerable to phenazine-assault, fungi inhabit microbial communities that contain phenazine producers. Because many fungi cannot withstand phenazine challenge, but some bacterial species can, we hypothesized that bacterial partners may protect fungi in phenazine-replete environments. In the first soil sample we collected, we co-isolated several such physically associated pairings. We discovered the novel species Paraburkholderia edwinii and demonstrated it can protect a co-isolated Aspergillus species from phenazine-1-carboxylic acid (PCA) by sequestering it, acting as a toxin sponge; in turn, it also gains protection. When challenged with PCA, P. edwinii changes its morphology, forming aggregates within the growing fungal colony. Further, the fungal partner triggers P. edwinii to sequester PCA and maintains conditions that limit PCA toxicity by promoting an anoxic and highly reducing environment. A mutagenic screen revealed this program depends on the stress-inducible transcriptional repressor HrcA. We show that one relevant stressor in response to PCA challenge is fungal acidification and that acid stress causes P. edwinii to behave as though the fungus were present. Finally, we reveal this phenomenon as widespread among Paraburkholderia with moderate specificity among bacterial and fungal partners, including plant and human pathogens. Our discovery suggests a common mechanism by which fungi can gain access to phenazine-replete environments, and provides a tractable model system for its study. These results have implications for how rhizosphere microbial communities as well as plant and human infection sites are policed for fungal membership.
]]></description>
<dc:creator>Dahlstrom, K. M.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2021-03-28</dc:date>
<dc:identifier>doi:10.1101/2021.03.28.437412</dc:identifier>
<dc:title><![CDATA[Paraburkholderia edwinii protects Aspergillus sp. from phenazines by acting as a toxin sponge]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.01.438014v1?rss=1">
<title>
<![CDATA[
IQCELL: A platform for predicting the effect of gene perturbations on developmental trajectories using single-cell RNA-seq data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.01.438014v1?rss=1</link>
<description><![CDATA[
The increasing availability of single-cell RNA-sequencing (scRNA-seq) data from various developmental systems provides the opportunity to infer gene regulatory networks (GRNs) directly from data. Herein we describe IQCELL, a platform to infer, simulate, and study executable logical GRNs directly from scRNA-seq data. Such executable GRNs provide an opportunity to inform fundamental hypotheses in developmental programs and help accelerate the design of stem cell-based technologies. We first describe the architecture of IQCELL. Next, we apply IQCELL to a scRNA-seq dataset of early mouse T-cell development and show that it can infer a priori over 75% of causal gene interactions previously reported via decades of research. We will also show that dynamic simulations of the derived GRN qualitatively recapitulate the effects of the known gene perturbations on the T-cell developmental trajectory. IQCELL is applicable to many developmental systems and offers a versatile tool to infer, simulate, and study GRNs in biological systems. (https://gitlab.com/stemcellbioengineering/iqcell)
]]></description>
<dc:creator>Heydari, T.</dc:creator>
<dc:creator>Langley, M. A.</dc:creator>
<dc:creator>Fisher, C.</dc:creator>
<dc:creator>Aguilar-Hidalgo, D.</dc:creator>
<dc:creator>Shukla, S.</dc:creator>
<dc:creator>Yachie-Kinoshita, A.</dc:creator>
<dc:creator>Hughes, M.</dc:creator>
<dc:creator>McNagny, K. M.</dc:creator>
<dc:creator>Zandstra, P. W.</dc:creator>
<dc:date>2021-04-03</dc:date>
<dc:identifier>doi:10.1101/2021.04.01.438014</dc:identifier>
<dc:title><![CDATA[IQCELL: A platform for predicting the effect of gene perturbations on developmental trajectories using single-cell RNA-seq data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.08.438894v1?rss=1">
<title>
<![CDATA[
IKKβ signaling mediates metabolic changes in the hypothalamus of a Huntington's disease mouse model 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.08.438894v1?rss=1</link>
<description><![CDATA[
BackgroundHuntingtons disease (HD) is a neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin (HTT) gene. Metabolic changes are associated with HD progression, and underlying mechanisms are not fully known. As the IKK{beta}/NF-{kappa}B pathway is an essential regulator of metabolism, we investigated the involvement of IKK{beta}, the upstream activator of NF-{kappa}B in hypothalamus-specific HD metabolic changes.

MethodsUsing viral vectors, we expressed amyloidogenic N-terminal fragments of mutant HTT (mHTT) fragments in the hypothalamus of mice without IKK{beta} in the CNS (IKK{beta}-/-) and control mice (IKK{beta}+/+). We assessed effects on body weight, metabolic hormones, and hypothalamic neuropathology.

ResultsHypothalamic expression of mHTT led to an obese phenotype only in female mice. CNS-specific inactivation of IKK{beta} prohibited weight gain in females, which was independent of neuroprotection and microglial activation.

ConclusionsThe expression of mHTT in the hypothalamus causes metabolic imbalance in a sex-specific fashion, and central inhibition of the IKK{beta} pathway attenuates the obese phenotype.
]]></description>
<dc:creator>Soylu Kucharz, R.</dc:creator>
<dc:creator>Khoshnan, A.</dc:creator>
<dc:creator>Petersen, A.</dc:creator>
<dc:date>2021-04-09</dc:date>
<dc:identifier>doi:10.1101/2021.04.08.438894</dc:identifier>
<dc:title><![CDATA[IKKβ signaling mediates metabolic changes in the hypothalamus of a Huntington's disease mouse model]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.12.439539v1?rss=1">
<title>
<![CDATA[
Targeted Neuronal Activation of the Gastrointestinal Tract Shapes the Environment of the Gut in Mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.12.439539v1?rss=1</link>
<description><![CDATA[
The gastrointestinal (GI) tract is extensively innervated by intrinsic neurons of the enteric nervous system (ENS) and extrinsic neurons of the central nervous system and peripheral ganglia, which together regulate gut physiology. The GI tract also harbors a diverse microbiome, but interactions between the ENS and the microbiome remain poorly understood. Herein, we activate choline acetyltransferase (ChAT)-expressing or tyrosine hydroxylase (TH)-expressing gut-associated neurons in mice to determine effects on intestinal microbial communities and their metabolites, as well as on host physiology. The resulting multi-omics datasets support broad roles for discrete peripheral neuronal subtypes in shaping microbiome structure, including modulating bile acid profiles and fungal colonization. Physiologically, activation of either ChAT+ or TH+ neurons increases fecal output, while only ChAT+ activation results in increased colonic migrating motor complexes and diarrhea-like fluid secretion. These findings suggest that specific subsets of peripherally-activated ENS neurons differentially regulate the gut microbiome and GI physiology in mice, without involvement of signals from the brain.
]]></description>
<dc:creator>Yoo, B. B.</dc:creator>
<dc:creator>Griffiths, J. A.</dc:creator>
<dc:creator>Thuy-Boun, P.</dc:creator>
<dc:creator>Cantu, V.</dc:creator>
<dc:creator>Weldon, K.</dc:creator>
<dc:creator>Challis, C.</dc:creator>
<dc:creator>Sweredoski, M. J.</dc:creator>
<dc:creator>Chan, K. Y.</dc:creator>
<dc:creator>Thron, T. M.</dc:creator>
<dc:creator>Sharon, G.</dc:creator>
<dc:creator>Moradian, A.</dc:creator>
<dc:creator>Humphrey, G.</dc:creator>
<dc:creator>Zhu, Q.</dc:creator>
<dc:creator>Shaffer, J.</dc:creator>
<dc:creator>Wolan, D. W.</dc:creator>
<dc:creator>Dorrestein, P.</dc:creator>
<dc:creator>Knight, R.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:creator>Mazmanian, S.</dc:creator>
<dc:date>2021-04-13</dc:date>
<dc:identifier>doi:10.1101/2021.04.12.439539</dc:identifier>
<dc:title><![CDATA[Targeted Neuronal Activation of the Gastrointestinal Tract Shapes the Environment of the Gut in Mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.14.439868v1?rss=1">
<title>
<![CDATA[
Thiophenesulfonamides are specific inhibitors of quorum sensing in pathogenic Vibrios 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.14.439868v1?rss=1</link>
<description><![CDATA[
Vibrio bacteria are pathogens of fish, shellfish, coral, and humans due to contaminated seafood consumption. Vibrio virulence factors are controlled by the cell-to-cell communication called quorum sensing, thus this signaling system is a promising target for therapeutic design. We screened a compound library and identified nine compounds, including several 2-thiophenesulfonamides, that inhibit the master quorum sensing transcription factor LuxR in Vibrio campbellii but do not affect cell growth. We synthesized a panel of 50 thiophenesulfonamide compounds to examine the structure-activity relationship effects on quorum sensing in vivo. The most potent molecule identified, PTSP (3-phenyl-1-(thiophen-2-ylsulfonyl)-1H-pyrazole), specifically inhibits LuxR homologs in multiple strains of Vibrio vulnificus, Vibrio parahaemolyticus, and V. campbellii with sub-micromolar concentrations. PTSP efficacy is driven by amino acid conservation in the binding pocket, which is accurately predicted using in silico modeling of inhibitors. Our results underscore the potential for developing thiophenesulfonamides as specific quorum sensing-directed treatments for Vibrio infections.
]]></description>
<dc:creator>Newman, J. D.</dc:creator>
<dc:creator>Shah, P.</dc:creator>
<dc:creator>Chopra, J.</dc:creator>
<dc:creator>Shi, E.</dc:creator>
<dc:creator>McFadden, M. E.</dc:creator>
<dc:creator>Horness, R. E.</dc:creator>
<dc:creator>Brown, L. C.</dc:creator>
<dc:creator>van Kessel, J. C.</dc:creator>
<dc:date>2021-04-14</dc:date>
<dc:identifier>doi:10.1101/2021.04.14.439868</dc:identifier>
<dc:title><![CDATA[Thiophenesulfonamides are specific inhibitors of quorum sensing in pathogenic Vibrios]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.16.440200v1?rss=1">
<title>
<![CDATA[
Sonicated fibrils of huntingtin exon-1 preferentially seed neurons and produce toxic assemblies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.16.440200v1?rss=1</link>
<description><![CDATA[
Huntingtons disease (HD) is a genetically inherited neurodegenerative disorder caused by expansion of a polyglutamine (polyQ) repeats in the exon-1 of huntingtin protein (HTT). The expanded polyQ enhances the amyloidogenic propensity of HTT exon 1 (HTTex1), which forms a heterogeneous mixture of assemblies with some being neurotoxic. While predominantly intracellular, monomeric and aggregated mutant HTT species are also present in the cerebrospinal fluids of HD patients, however, their biological properties are not well understood. To explore the role of extracellular mutant HTT in aggregation and toxicity, we investigated the possible uptake and amplification of recombinant HTTex1 assemblies in cell culture models. We found seeding-competent species in the sonicated HTTex1 fibrils, which preferentially entered human neurons and triggered the amplification of neurotoxic assemblies; astrocytes or epithelial cells were not permissive to the HTTex1 seeding. The aggregation of HTTex1 seeds in neurons depleted endogenous HTT protein with non-pathogenic polyQ repeat, activated apoptotic caspase-3 pathway and induced nuclear fragmentation. Using a panel of novel monoclonal antibodies and genetic mutation, we identified epitopes within the N-terminal 17 amino acids and proline-rich domain of HTTex1 mediating neural seeding. Synaptosome preparations from the brains of HD mice also contained similar neurotoxic seeding-competent mutant HTT species. Our findings suggest that amyloidogenic extracellular mutant HTT assemblies may selectively enter neurons, propagate and produce neurotoxic assemblies.
]]></description>
<dc:creator>Chongtham, A.</dc:creator>
<dc:creator>Isas, J. M.</dc:creator>
<dc:creator>Pandey, N. K.</dc:creator>
<dc:creator>Rawat, A.</dc:creator>
<dc:creator>Yoo, J. H.</dc:creator>
<dc:creator>Mastro, T. L.</dc:creator>
<dc:creator>Kennedy, M.</dc:creator>
<dc:creator>Langen, R.</dc:creator>
<dc:creator>Khoshnan, A.</dc:creator>
<dc:date>2021-04-18</dc:date>
<dc:identifier>doi:10.1101/2021.04.16.440200</dc:identifier>
<dc:title><![CDATA[Sonicated fibrils of huntingtin exon-1 preferentially seed neurons and produce toxic assemblies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.23.441195v1?rss=1">
<title>
<![CDATA[
Broad cross-reactivity across sarbecoviruses exhibited by a subset of COVID-19 donor-derived neutralizing antibodies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.23.441195v1?rss=1</link>
<description><![CDATA[
Many anti-SARS-CoV-2 neutralizing antibodies target the ACE2-binding site on viral spike receptor-binding domains (RBDs). The most potent antibodies recognize exposed variable epitopes, often rendering them ineffective against other sarbecoviruses and SARS-CoV-2 variants. Class 4 anti-RBD antibodies against a less-exposed, but more-conserved, cryptic epitope could recognize newly-emergent zoonotic sarbecoviruses and variants, but usually show only weak neutralization potencies. We characterized two class 4 anti-RBD antibodies derived from COVID-19 donors that exhibited broad recognition and potent neutralization of zoonotic coronavirus and SARS-CoV-2 variants. C118-RBD and C022-RBD structures revealed CDRH3 mainchain H-bond interactions that extended an RBD {beta}-sheet, thus reducing sensitivity to RBD sidechain changes, and epitopes that extended from the cryptic epitope to occlude ACE2 binding. A C118-spike trimer structure revealed rotated RBDs to allow cryptic epitope access and the potential for intra-spike crosslinking to increase avidity. These studies facilitate vaccine design and illustrate potential advantages of class 4 RBD-binding antibody therapeutics.
]]></description>
<dc:creator>Jette, C. A.</dc:creator>
<dc:creator>Cohen, A. A.</dc:creator>
<dc:creator>Gnanapragasam, P. N. P.</dc:creator>
<dc:creator>Muecksch, F.</dc:creator>
<dc:creator>Lee, Y. E.</dc:creator>
<dc:creator>Huey-Tubman, K. E.</dc:creator>
<dc:creator>Schmidt, F.</dc:creator>
<dc:creator>Hatziioannou, T.</dc:creator>
<dc:creator>Bieniasz, P. D.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>Bjorkman, P.</dc:creator>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:date>2021-04-26</dc:date>
<dc:identifier>doi:10.1101/2021.04.23.441195</dc:identifier>
<dc:title><![CDATA[Broad cross-reactivity across sarbecoviruses exhibited by a subset of COVID-19 donor-derived neutralizing antibodies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.25.441372v1?rss=1">
<title>
<![CDATA[
Control-theoretic immune tradeoffs explain SARS-CoV-2 virulence and transmission variation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.25.441372v1?rss=1</link>
<description><![CDATA[
Dramatic variation in SARS-CoV-2 virulence and transmission between hosts has driven the COVID-19 pandemic. The complexity and dynamics of the immune response present a challenge to understanding variation in SARS-CoV-2 infections. To address this challenge, we apply control theory, a framework used to study complex feedback systems, to establish rigorous mathematical bounds on immune responses. Two mechanisms of SARS-CoV-2 biology are sufficient to create extreme variation between hosts: (1) a sparsely expressed host receptor and (2) potent, but not unique, suppression of interferon. The resulting model unifies disparate and unexplained features of the SARS-CoV-2 pandemic, predicts features of future viruses that threaten to cause pandemics, and identifies potential interventions.
]]></description>
<dc:creator>Sarma, A. A.</dc:creator>
<dc:creator>Sarma, A.</dc:creator>
<dc:creator>Csete, M.</dc:creator>
<dc:creator>Lee, P. P.</dc:creator>
<dc:creator>Doyle, J. C.</dc:creator>
<dc:date>2021-04-26</dc:date>
<dc:identifier>doi:10.1101/2021.04.25.441372</dc:identifier>
<dc:title><![CDATA[Control-theoretic immune tradeoffs explain SARS-CoV-2 virulence and transmission variation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.26.441537v1?rss=1">
<title>
<![CDATA[
Genomically Mined Acoustic Reporter Genes Enable On-Demand In Vivo Monitoring of Tumor-Homing Bacteria 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.26.441537v1?rss=1</link>
<description><![CDATA[
A major outstanding challenge in the fields of biological research, synthetic biology and cell-based medicine is visualizing the function of natural and engineered cells noninvasively inside opaque organisms. Ultrasound imaging has the potential to address this challenge as a widely available technique with a tissue penetration of several centimeters and spatial resolution below 100 m. Recently, the first genetically encoded acoustic reporters were developed based on bacterial gas vesicles to link ultrasound signals to molecular and cellular function. However, the properties of these first-generation acoustic reporter genes (ARGs) resulted in limited sensitivity and specificity for imaging gene expression in vivo. Here, we describe second-generation ARGs with greatly improved acoustic properties and expression characteristics, identified through a phylogenetic screen of candidate gene clusters from diverse bacteria and archaea. The resulting constructs offer major qualitative and quantitative improvements, including much stronger ultrasound contrast, the ability to produce nonlinear signals distinguishable from background tissue, and stable long-term expression. We demonstrate the capabilities of these next-generation ARGs by imaging in situ gene expression in mouse models of breast cancer and tumor-homing therapeutic bacteria, noninvasively revealing the unique spatial distributions of tumor growth and colonization by therapeutic cells in living subjects and providing real-time guidance for interventions such as needle biopsies.
]]></description>
<dc:creator>Hurt, R. C.</dc:creator>
<dc:creator>Buss, M. T.</dc:creator>
<dc:creator>Wong, K.</dc:creator>
<dc:creator>Sawyer, D. P.</dc:creator>
<dc:creator>Swift, M. B.</dc:creator>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Mittelstein, D. R.</dc:creator>
<dc:creator>Jin, Z.</dc:creator>
<dc:creator>Abedi, M. H.</dc:creator>
<dc:creator>Deshpande, R.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2021-04-27</dc:date>
<dc:identifier>doi:10.1101/2021.04.26.441537</dc:identifier>
<dc:title><![CDATA[Genomically Mined Acoustic Reporter Genes Enable On-Demand In Vivo Monitoring of Tumor-Homing Bacteria]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.26.441547v1?rss=1">
<title>
<![CDATA[
Integrated spatial genomics in tissues reveals invariant and cell type dependent nuclear architecture 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.26.441547v1?rss=1</link>
<description><![CDATA[
Nuclear architecture in tissues can arise from cell-type specific organization of nuclear bodies, chromatin states and chromosome structures. However, the lack of genome-wide measurements to interrelate such modalities within single cells limits our overall understanding of nuclear architecture. Here, we demonstrate integrated spatial genomics in the mouse brain cortex, imaging thousands of genomic loci along with RNAs and subnuclear markers simultaneously in individual cells. We revealed chromatin fixed points, combined with cell-type specific organization of nuclear bodies, arrange the interchromosomal organization and radial positioning of chromosomes in diverse cell types. At the sub-megabase level, we uncovered a collection of single-cell chromosome domain structures, including those for the active and inactive X chromosomes. These results advance our understanding of single-cell nuclear architecture in complex tissues.
]]></description>
<dc:creator>Takei, Y.</dc:creator>
<dc:creator>Zheng, S.</dc:creator>
<dc:creator>Yun, J.</dc:creator>
<dc:creator>Shah, S.</dc:creator>
<dc:creator>Pierson, N.</dc:creator>
<dc:creator>White, J.</dc:creator>
<dc:creator>Schindler, S.</dc:creator>
<dc:creator>Tischbirek, C.</dc:creator>
<dc:creator>Yuan, G.-C.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:date>2021-04-27</dc:date>
<dc:identifier>doi:10.1101/2021.04.26.441547</dc:identifier>
<dc:title><![CDATA[Integrated spatial genomics in tissues reveals invariant and cell type dependent nuclear architecture]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.28.441833v1?rss=1">
<title>
<![CDATA[
scvi-tools: a library for deep probabilistic analysis of single-cell omics data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.28.441833v1?rss=1</link>
<description><![CDATA[
AO_SCPLOWBSTRACTC_SCPLOWProbabilistic models have provided the underpinnings for state-of-the-art performance in many single-cell omics data analysis tasks, including dimensionality reduction, clustering, differential expression, annotation, removal of unwanted variation, and integration across modalities. Many of the models being deployed are amenable to scalable stochastic inference techniques, and accordingly they are able to process single-cell datasets of realistic and growing sizes. However, the community-wide adoption of probabilistic approaches is hindered by a fractured software ecosystem resulting in an array of packages with distinct, and often complex interfaces. To address this issue, we developed scvi-tools (https://scvi-tools.org), a Python package that implements a variety of leading probabilistic methods. These methods, which cover many fundamental analysis tasks, are accessible through a standardized, easy-to-use interface with direct links to Scanpy, Seurat, and Bioconductor workflows. By standardizing the implementations, we were able to develop and reuse novel functionalities across different models, such as support for complex study designs through nonlinear removal of unwanted variation due to multiple covariates and reference-query integration via scArches. The extensible software building blocks that underlie scvi-tools also enable a developer environment in which new probabilistic models for single cell omics can be efficiently developed, benchmarked, and deployed. We demonstrate this through a code-efficient reimplementation of Stereoscope for deconvolution of spatial transcriptomics profiles. By catering to both the end user and developer audiences, we expect scvi-tools to become an essential software dependency and serve to formulate a community standard for probabilistic modeling of single cell omics.
]]></description>
<dc:creator>Gayoso, A.</dc:creator>
<dc:creator>Lopez, R.</dc:creator>
<dc:creator>Xing, G.</dc:creator>
<dc:creator>Boyeau, P.</dc:creator>
<dc:creator>Wu, K.</dc:creator>
<dc:creator>Jayasuriya, M.</dc:creator>
<dc:creator>Mehlman, E.</dc:creator>
<dc:creator>Langevin, M.</dc:creator>
<dc:creator>Liu, Y.</dc:creator>
<dc:creator>Samaran, J.</dc:creator>
<dc:creator>Misrachi, G.</dc:creator>
<dc:creator>Nazaret, A.</dc:creator>
<dc:creator>Clivio, O.</dc:creator>
<dc:creator>Xu, C.</dc:creator>
<dc:creator>Ashuach, T.</dc:creator>
<dc:creator>Lotfollahi, M.</dc:creator>
<dc:creator>Svensson, V.</dc:creator>
<dc:creator>da Veiga Beltrame, E.</dc:creator>
<dc:creator>Talavera-Lopez, C.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Theis, F. J.</dc:creator>
<dc:creator>Streets, A.</dc:creator>
<dc:creator>Jordan, M. I.</dc:creator>
<dc:creator>Regier, J.</dc:creator>
<dc:creator>Yosef, N.</dc:creator>
<dc:date>2021-04-29</dc:date>
<dc:identifier>doi:10.1101/2021.04.28.441833</dc:identifier>
<dc:title><![CDATA[scvi-tools: a library for deep probabilistic analysis of single-cell omics data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.28.441877v1?rss=1">
<title>
<![CDATA[
Selection of Sites for Field Trials of Genetically Engineered Mosquitoes with Gene Drive. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.28.441877v1?rss=1</link>
<description><![CDATA[
Novel malaria control strategies using genetically engineered mosquitoes (GEMs) are on the horizon. Population modification is one approach wherein mosquitoes are engineered with genes rendering them refractory to the malaria parasite coupled with a low-threshold, Cas9-based gene drive. When released into a wild vector population, GEMs preferentially transmit these beneficial genes to their offspring, ultimately modifying a vector population into a non-vector one. Deploying this technology awaits evaluation including ecologically contained field trials. Here, we consider a process for site selection, the first critical step in designing a trial. Our goal is to identify a site that maximizes prospects for success, minimizes risk, and serves as a fair, valid, and convincing test of efficacy and impacts of a GEM product intended for large-scale deployment in Africa. We base site selection on geographical, geological, and biological, rather than social or legal, criteria. We recognize the latter as critically important but not preeminent. We propose physical islands as being the best candidates for a GEM field trial and present an evaluation of 22 African islands. We consider geographic and genetic isolation, biological complexity, island size, topography, and identify two island groups that satisfy key criteria for ideal GEM field trial sites.
]]></description>
<dc:creator>Lanzaro, G. C.</dc:creator>
<dc:creator>Campos, M.</dc:creator>
<dc:creator>Crepeau, M.</dc:creator>
<dc:creator>Cornel, A.</dc:creator>
<dc:creator>Estrada, A.</dc:creator>
<dc:creator>Gripkey, H.</dc:creator>
<dc:creator>Haddad, Z.</dc:creator>
<dc:creator>Kormos, A.</dc:creator>
<dc:creator>Palomares, S.</dc:creator>
<dc:creator>Sharpee, W.</dc:creator>
<dc:date>2021-04-28</dc:date>
<dc:identifier>doi:10.1101/2021.04.28.441877</dc:identifier>
<dc:title><![CDATA[Selection of Sites for Field Trials of Genetically Engineered Mosquitoes with Gene Drive.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.29.441975v1?rss=1">
<title>
<![CDATA[
Virtual partition digital PCR for high precision chromosomal counting applications 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.29.441975v1?rss=1</link>
<description><![CDATA[
Digital PCR (dPCR) is the gold standard analytical platform for rapid high precision quantification of genomic fragments. However, current dPCR assays are generally limited to monitoring 1-2 analytes per sample, thereby limiting the platforms ability to address some clinical applications that require the simultaneous monitoring of 20 - 50 analytes per sample. Here we present Virtual Partition dPCR (VPdPCR), a novel analysis methodology enabling the detection of 10 or more target regions per color channel using conventional dPCR hardware and workflow. Furthermore, VPdPCR enables dPCR instruments to overcome upper quantitation limits caused by partitioning error. While traditional dPCR analysis establishes a single threshold to separate negative and positive partitions, VPdPCR establishes multiple thresholds to identify the number of unique targets present in each positive droplet based on fluorescent intensity. Each physical partition is then divided into a series of virtual partitions, and the resulting increase in partition count substantially decreases partitioning error. We present both a theoretical analysis of the advantages of VPdPCR and an experimental demonstration in the form of a 20-plex assay for non-invasive fetal aneuploidy testing. This demonstration assay - tested on 432 samples contrived from sheared cell-line DNA at multiple input concentrations and simulated fractions of euploid or trisomy-21 "fetal" DNA - is analyzed using both traditional dPCR thresholding and VPdPCR. VPdPCR analysis significantly lowers variance of chromosome ratio across replicates and increases the accuracy of trisomy identification when compared to traditional dPCR, yielding >98% single-well sensitivity and specificity. VPdPCR has substantial promise for increasing the utility of dPCR in applications requiring ultra-high-precision quantitation.
]]></description>
<dc:creator>Jacky, L.</dc:creator>
<dc:creator>Yurk, D.</dc:creator>
<dc:creator>Alvarado, J.</dc:creator>
<dc:creator>Leatham, B.</dc:creator>
<dc:creator>Schwartz, J.</dc:creator>
<dc:creator>MacDonald, C.</dc:creator>
<dc:creator>Rajagopal, A.</dc:creator>
<dc:date>2021-04-29</dc:date>
<dc:identifier>doi:10.1101/2021.04.29.441975</dc:identifier>
<dc:title><![CDATA[Virtual partition digital PCR for high precision chromosomal counting applications]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.05.04.442564v1?rss=1">
<title>
<![CDATA[
Characterization of the ABC methionine transporter from Neisseria meningitidis reveals that MetQ is a lipoprotein 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.05.04.442564v1?rss=1</link>
<description><![CDATA[
NmMetQ is a substrate binding protein (SBP) from Neisseria meningitidis that has been identified as a surface-exposed candidate antigen for meningococcal vaccines. However, this location for NmMetQ challenges the prevailing view that SBPs in Gram-negative bacteria are localized to the periplasmic space to promote interaction with their cognate ABC transporter embedded in the bacterial inner membrane. To address the roles of NmMetQ, we characterized NmMetQ with and without its cognate ABC transporter (NmMetNI). Here, we show that NmMetQ is a lipoprotein (lipo-NmMetQ) that binds multiple methionine analogs and stimulates the ATPase activity of NmMetNI. Using single-particle electron cryo-microscopy, we determined the structures of NmMetNI in the absence and presence of lipo-NmMetQ. Based on our data, we propose that NmMetQ tethers to membranes via a lipid anchor and has dual function/topology, playing a role in NmMetNI-mediated transport at the inner-membrane in addition to moonlighting functions on the bacterial surface.
]]></description>
<dc:creator>Sharaf, N. G.</dc:creator>
<dc:creator>Shahgholi, M.</dc:creator>
<dc:creator>Kim, E.</dc:creator>
<dc:creator>Lai, J. Y.</dc:creator>
<dc:creator>VanderVelde, D. G.</dc:creator>
<dc:creator>Lee, A. T.</dc:creator>
<dc:creator>Rees, D. C.</dc:creator>
<dc:date>2021-05-04</dc:date>
<dc:identifier>doi:10.1101/2021.05.04.442564</dc:identifier>
<dc:title><![CDATA[Characterization of the ABC methionine transporter from Neisseria meningitidis reveals that MetQ is a lipoprotein]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.05.07.443175v1?rss=1">
<title>
<![CDATA[
Vaccination boosts naturally enhanced neutralizing breadth to SARS-CoV-2 one year after infection 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.05.07.443175v1?rss=1</link>
<description><![CDATA[
Over one year after its inception, the coronavirus disease-2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) remains difficult to control despite the availability of several excellent vaccines. Progress in controlling the pandemic is slowed by the emergence of variants that appear to be more transmissible and more resistant to antibodies1,2. Here we report on a cohort of 63 COVID-19-convalescent individuals assessed at 1.3, 6.2 and 12 months after infection, 41% of whom also received mRNA vaccines3,4. In the absence of vaccination antibody reactivity to the receptor binding domain (RBD) of SARS-CoV-2, neutralizing activity and the number of RBD-specific memory B cells remain relatively stable from 6 to 12 months. Vaccination increases all components of the humoral response, and as expected, results in serum neutralizing activities against variants of concern that are comparable to or greater than neutralizing activity against the original Wuhan Hu-1 achieved by vaccination of naive individuals2,5-8. The mechanism underlying these broad-based responses involves ongoing antibody somatic mutation, memory B cell clonal turnover, and development of monoclonal antibodies that are exceptionally resistant to SARS-CoV-2 RBD mutations, including those found in variants of concern4,9. In addition, B cell clones expressing broad and potent antibodies are selectively retained in the repertoire over time and expand dramatically after vaccination. The data suggest that immunity in convalescent individuals will be very long lasting and that convalescent individuals who receive available mRNA vaccines will produce antibodies and memory B cells that should be protective against circulating SARS-CoV-2 variants.
]]></description>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>Muecksch, F.</dc:creator>
<dc:creator>Schaefer-Babajew, D.</dc:creator>
<dc:creator>Finkin, S.</dc:creator>
<dc:creator>Viant, C.</dc:creator>
<dc:creator>Gaebler, C.</dc:creator>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Cipolla, M.</dc:creator>
<dc:creator>Ramos, V.</dc:creator>
<dc:creator>Oliveira, T. Y.</dc:creator>
<dc:creator>Cho, A.</dc:creator>
<dc:creator>Schmidt, F.</dc:creator>
<dc:creator>Silva, J. D.</dc:creator>
<dc:creator>Bednarski, E.</dc:creator>
<dc:creator>Daga, M.</dc:creator>
<dc:creator>Turroja, M.</dc:creator>
<dc:creator>Millard, K. G.</dc:creator>
<dc:creator>Jankovic, M.</dc:creator>
<dc:creator>Gazumyan, A.</dc:creator>
<dc:creator>Bieniasz, P. D.</dc:creator>
<dc:creator>Caskey, M.</dc:creator>
<dc:creator>Hatziioannou, T.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:date>2021-05-09</dc:date>
<dc:identifier>doi:10.1101/2021.05.07.443175</dc:identifier>
<dc:title><![CDATA[Vaccination boosts naturally enhanced neutralizing breadth to SARS-CoV-2 one year after infection]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.05.11.443152v1?rss=1">
<title>
<![CDATA[
Museum of Spatial Transcriptomics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.05.11.443152v1?rss=1</link>
<description><![CDATA[
The function of many biological systems, such as embryos, liver lobules, intestinal villi, and tumors depends on the spatial organization of their cells. In the past decade high-throughput technologies have been developed to quantify gene expression in space, and computational methods have been developed that leverage spatial gene expression data to identify genes with spatial patterns and to delineate neighborhoods within tissues. To assess the ability and potential of spatial gene expression technologies to drive biological discovery, we present a curated database of literature on spatial transcriptomics dating back to 1987, along with a thorough analysis of trends in the field such as usage of experimental techniques, species, tissues studied and computational approaches used. Our analysis places current methods in historical context, and we derive insights about the field that can guide current research strategies. A companion supplement offers a more detailed look at the technologies and methods analyzed: https://pachterlab.github.io/LP_2021/.
]]></description>
<dc:creator>Moses, L.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2021-05-12</dc:date>
<dc:identifier>doi:10.1101/2021.05.11.443152</dc:identifier>
<dc:title><![CDATA[Museum of Spatial Transcriptomics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.05.13.444042v1?rss=1">
<title>
<![CDATA[
Evolutionary assembly of cooperating cell types in an animal chemical defense system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.05.13.444042v1?rss=1</link>
<description><![CDATA[
A long-standing challenge in biology is explaining how the functions of multicellular organs emerge from the underlying evolution of cell types. We deconstructed evolution of an organ novelty: a rove beetle gland that secretes a defensive cocktail. We show that gland function was pieced together via assembly of two cell types that manufacture distinct compounds. One cell type forms a chemical reservoir in the beetles abdomen and produces alkane and ester compounds. We demonstrate that this cell type is a hybrid of cuticle cells and ancient pheromone and adipocyte-like cells, and executes its function via a mosaic of enzymes sourced from each parental cell type. The second cell type synthesizes noxious benzoquinones using a chimeric pathway derived from conserved cellular energy and cuticle formation pathways. We present evidence that evolution of each cell type was shaped by coevolution between the two cell types: the benzoquinones produced by the second cell type dissolve in solvents produced by the first, yielding a potent secretion that confers adaptive value onto the gland as a whole. Our findings illustrate how cooperation between cell types can arise, generating new, organ-level behaviors.
]]></description>
<dc:creator>Bruckner, A.</dc:creator>
<dc:creator>Badroos, J.</dc:creator>
<dc:creator>Learsch, R. W.</dc:creator>
<dc:creator>Yousefelahiyeh, M.</dc:creator>
<dc:creator>Kitchen, S. A.</dc:creator>
<dc:creator>Parker, J.</dc:creator>
<dc:date>2021-05-15</dc:date>
<dc:identifier>doi:10.1101/2021.05.13.444042</dc:identifier>
<dc:title><![CDATA[Evolutionary assembly of cooperating cell types in an animal chemical defense system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.05.17.444566v1?rss=1">
<title>
<![CDATA[
Thermodynamics drives coenzyme redundancy in metabolism 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.05.17.444566v1?rss=1</link>
<description><![CDATA[
Coenzymes distribute a variety of chemical moieties throughout cellular metabolism, participating in group (e.g., phosphate, acyl) and electron transfer. For a variety of reactions requiring acceptors or donors of specific resources, there often exist degenerate sets of molecules (e.g., NAD(H) and NADP(H)) that carry out similar functions. Although the physiological roles of various coenzyme systems are well established, it is unclear what selective pressures may have driven the emergence of coenzyme redundancy. Here we use genome-wide metabolic modeling approaches to decompose the selective pressures driving enzymatic specificity for either NAD(H) or NADP(H) in the metabolic network of Escherichia coli. We found that few enzymes are thermodynamically constrained to using a single coenzyme, and in principle, a metabolic network relying on only NAD(H) is feasible. However, structural and sequence analyses revealed widespread conservation of residues that retain selectivity for either NAD(H) or NADP(H), suggesting that additional forces may shape specificity. Using a model accounting for the cost of oxidoreductase enzyme expression, we found that coenzyme redundancy universally reduces the minimal amount of protein required to catalyze coenzyme-coupled reactions, inducing individual reactions to strongly prefer one coenzyme over another when reactions are near thermodynamic equilibrium. We propose that protein minimization generically promotes coenzyme redundancy, and that coenzymes typically thought to exist in a single pool (e.g., CoA) may exist in more than one form (e.g., dephospho-CoA).

Significance statementMetabolism relies on a small class of molecules (coenzymes) that serve as universal donors and acceptors of key chemical groups and electrons. Although metabolic networks crucially depend on structurally redundant coenzymes (e.g., NAD(H) and NADP(H)) associated with different enzymes, the criteria that led to the emergence of this redundancy remain poorly understood. Our combination of modeling, and structural and sequence analysis indicates that coenzyme redundancy is not essential for metabolism, but rather an evolved strategy promoting efficient usage of enzymes when biochemical reactions are near equilibrium. Our work suggests that early metabolism may have operated with fewer coenzymes, and that adaptation for metabolic efficiency may have driven the rise of coenzyme diversity in living systems.
]]></description>
<dc:creator>Goldford, J. E.</dc:creator>
<dc:creator>George, A. B.</dc:creator>
<dc:creator>Flamholz, A. E.</dc:creator>
<dc:creator>Segre, D.</dc:creator>
<dc:date>2021-05-18</dc:date>
<dc:identifier>doi:10.1101/2021.05.17.444566</dc:identifier>
<dc:title><![CDATA[Thermodynamics drives coenzyme redundancy in metabolism]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.05.18.444561v1?rss=1">
<title>
<![CDATA[
Ultrafast amplitude modulation for molecular and hemodynamic ultrasound imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.05.18.444561v1?rss=1</link>
<description><![CDATA[
Ultrasound is playing an emerging role in molecular and cellular imaging thanks to new micro- and nanoscale contrast agents and reporter genes. Acoustic methods for the selective in vivo detection of these imaging agents are needed to maximize their impact in biology and medicine. Existing ultrasound pulse sequences use the nonlinearity in contrast agents response to acoustic pressure to distinguish them from mostly linear tissue scattering. However, such pulse sequences typically scan the sample using focused transmissions, resulting in a limited frame rate and restricted field of view. Meanwhile, existing wide-field scanning techniques based on plane wave transmissions suffer from limited sensitivity or nonlinear artifacts. To overcome these limitations, we introduce an ultrafast nonlinear imaging modality combining amplitude-modulated pulses, multiplane wave transmissions and selective coherent compounding. This technique achieves contrast imaging sensitivity comparable to much slower gold-standard amplitude modulation sequences and enables the acquisition of larger and deeper fields of view, while providing a much faster imaging framerate of 3.2kHz. Additionally, it enables simultaneous nonlinear and linear image formation, and allows concurrent monitoring of phenomena accessible only at ultrafast framerates, such as blood volume variations. We demonstrate the performance of this ultrafast amplitude modulation (uAM) technique by imaging gas vesicles, an emerging class of genetically encodable biomolecular contrast agents, in several in vitro and in vivo contexts. These demonstrations include the rapid discrimination of moving contrast agents and the real-time monitoring of phagolysosomal function in the mouse liver.
]]></description>
<dc:creator>Rabut, C.</dc:creator>
<dc:creator>Wu, D.</dc:creator>
<dc:creator>Ling, B.</dc:creator>
<dc:creator>Jin, Z.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2021-05-20</dc:date>
<dc:identifier>doi:10.1101/2021.05.18.444561</dc:identifier>
<dc:title><![CDATA[Ultrafast amplitude modulation for molecular and hemodynamic ultrasound imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.05.18.444705v1?rss=1">
<title>
<![CDATA[
Open-Source Thermometer, Temperature Controller, and Light Meter for Use in Animal Facilities and During Experiments 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.05.18.444705v1?rss=1</link>
<description><![CDATA[
Experiments with biological samples require precise control of environmental conditions. In our work we use zebrafish (Danio rerio) to understand the neurobiology of sleep, which requires precise control of temperature and lighting. Like many labs, lighting and temperature in the animal facility are centrally controlled in the building. During behavioral experiments and microscopy sessions, we use custom-built heating systems and perform occasional manual checks of conditions. However, without a system to precisely record conditions, gradual changes in temperature can go unnoticed for a long time, and temporary failures may be missed entirely. Here we present the design and characterization of affordable open-source tools to record temperature and light conditions during animal experiments using an Arduino microcontroller or a Raspberry Pi compact computer. The waterproof temperature sensor has high stability over 50 days of recording and is precise to 0.1{degrees}C. The Arduino device can be used through a common serial port interface for which we present code in Python and MATLAB. The Raspberry Pi version can be accessed through a web interface, for which we provide an installation guide. We use the device to record and review temperature and lighting conditions in two zebrafish animal facilities. We use our platform to add a water heating system to maintain temperature at 28{degrees}C during in vivo light-sheet imaging of larval zebrafish. We show that a change in temperature from 28{degrees}C to 32{degrees}C affects resting heart rate of the animal, highlighting the importance of maintaining and recording conditions. The protocols presented here do not require advanced engineering, fabrication, or software skills, and provide an approach to accurately record and report experimental conditions.
]]></description>
<dc:creator>Andreev, A.</dc:creator>
<dc:creator>Vasnarungruengkul, P.</dc:creator>
<dc:creator>Wagenaar, D. A.</dc:creator>
<dc:creator>Prober, D. A.</dc:creator>
<dc:date>2021-05-20</dc:date>
<dc:identifier>doi:10.1101/2021.05.18.444705</dc:identifier>
<dc:title><![CDATA[Open-Source Thermometer, Temperature Controller, and Light Meter for Use in Animal Facilities and During Experiments]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.05.25.445718v1?rss=1">
<title>
<![CDATA[
The globular C1q receptor is required for epidermal growth factor receptor signaling during Candida albicans infection 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.05.25.445718v1?rss=1</link>
<description><![CDATA[
During oropharyngeal candidiasis, Candida albicans activates the epidermal growth factor receptor (EGFR), which induces oral epithelial cells to both endocytose the fungus and synthesize proinflammatory mediators that orchestrate the host immune response. To elucidate the signaling pathways that are stimulated when C. albicans interacts with EGFR, we analyzed the proteins that associate with EGFR when C. albicans infects human oral epithelial cells. We identified 1214 proteins that were associated with EGFR in C. albicans-infected cells. We investigated the function of seven of these proteins that either showed increased association with EGFR in response to C. albicans or that mediated the interaction of other microbial pathogens with epithelial cells. Among these proteins, EGFR was found to associate with WW domain-binding protein 2, toll-interacting protein, interferon-induced transmembrane protein 3, and the globular C1q receptor (gC1qR) in viable epithelial cells. Each of these proteins was required for maximal endocytosis of C. albicans and they all regulated fungal-induced production of IL-1{beta} and/or IL-8, either positively or negatively. gC1qR functioned as a key coreceptor with EGFR. Interacting with the C. albicans Als3 invasin, gC1qR was required for the fungus to stimulate both EGFR and the ephrin type-A receptor 2. The combination of gC1qR and EGFR was necessary for maximal endocytosis of C. albicans and secretion of IL-1{beta}, IL-8, and GM-CSF. Thus, this work provides an atlas of proteins that associate with EGFR and identifies several that play a central role in the response of human oral epithelial cells to C. albicans infection.

IMPORTANCEOral epithelial cells play a key role in the pathogenesis of oropharyngeal candidiasis. In addition to being target host cells for C. albicans adherence and invasion, they secrete proinflammatory cytokines and chemokines that recruit T cells and activated phagocytes to foci of infection. It is known that C. albicans activates EGFR on oral epithelial cells, which induces these cells to endocytose the organism and stimulates them to secrete proinflammatory mediators. To elucidate the EGFR signaling pathways that govern these responses, we analyzed the epithelial cell proteins that associate with EGFR in C. albicans-infected epithelial cells. We identified four proteins that physically associate with EGFR and that regulate different aspects of the epithelial response to C. albicans. One of these is gC1qR, which is required for C. albicans to activate EGFR, induce endocytosis, and stimulate the secretion of proinflammatory mediators, indicating that gC1qR functions as a key co-receptor with EGFR.
]]></description>
<dc:creator>Phan, Q. T.</dc:creator>
<dc:creator>Lin, J.</dc:creator>
<dc:creator>Solis, N. V.</dc:creator>
<dc:creator>Eng, M.</dc:creator>
<dc:creator>Swidergall, M.</dc:creator>
<dc:creator>Wang, F.</dc:creator>
<dc:creator>LI, S.</dc:creator>
<dc:creator>Gaffen, S. L.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Filler, S. G.</dc:creator>
<dc:date>2021-05-26</dc:date>
<dc:identifier>doi:10.1101/2021.05.25.445718</dc:identifier>
<dc:title><![CDATA[The globular C1q receptor is required for epidermal growth factor receptor signaling during Candida albicans infection]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.06.02.446311v1?rss=1">
<title>
<![CDATA[
Hybridization chain reaction enables a unified approach to multiplexed, quantitative, high-resolution immunohistochemistry and in situ hybridization 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.06.02.446311v1?rss=1</link>
<description><![CDATA[
RNA in situ hybridization (RNA-ISH) based on the mechanism of hybridization chain reaction (HCR) enables multiplexed, quantitative, high-resolution RNA imaging in highly autofluorescent samples including whole-mount vertebrate embryos, thick brain slices, and formalin-fixed paraffin-embedded (FFPE) tissue sections. Here, we extend the benefits of 1-step, multiplexed, quantitative, isothermal, enzyme-free HCR signal amplification to immunohistochemistry (IHC), enabling accurate and precise protein relative quantitation with subcellular resolution in an anatomical context. More-over, we provide a unified framework for simultaneous quantitative protein and RNA imaging with 1-step HCR signal amplification performed for all target proteins and RNAs simultaneously.

SUMMARYSignal amplification based on the mechanism of hybridization chain reaction enables multiplexed, quantitative, high-resolution imaging of protein and RNA targets in highly autofluorescent tissues.
]]></description>
<dc:creator>Schwarzkopf, M.</dc:creator>
<dc:creator>Liu, M. C.</dc:creator>
<dc:creator>Schulte, S. J.</dc:creator>
<dc:creator>Ives, R.</dc:creator>
<dc:creator>Husain, N.</dc:creator>
<dc:creator>Choi, H. M. T.</dc:creator>
<dc:creator>Pierce, N.</dc:creator>
<dc:date>2021-06-02</dc:date>
<dc:identifier>doi:10.1101/2021.06.02.446311</dc:identifier>
<dc:title><![CDATA[Hybridization chain reaction enables a unified approach to multiplexed, quantitative, high-resolution immunohistochemistry and in situ hybridization]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-06-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.06.04.447179v1?rss=1">
<title>
<![CDATA[
Nitrate reduction stimulates and is stimulated by phenazine-1-carboxylic acid oxidation by Citrobacter portucalensis MBL 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.06.04.447179v1?rss=1</link>
<description><![CDATA[
Phenazines are secreted metabolites that microbes use in diverse ways, from quorum sensing to antimicrobial warfare to energy conservation. Phenazines are able to contribute to these activities due to their redox activity. The physiological consequences of cellular phenazine reduction have been extensively studied, but the counterpart phenazine oxidation has been largely overlooked. Phenazine-1-carboxylic acid (PCA) is common in the environment and readily reduced by its producers. Here, we describe its anaerobic oxidation by Citrobacter portucalensis strain MBL, which was isolated from topsoil in Falmouth, MA, and which does not produce phenazines itself. This activity depends on the availability of a suitable terminal electron acceptor, specifically nitrate. When C. portucalensis MBL is provided reduced PCA and nitrate, it rapidly oxidizes the PCA. We compared this terminal electron acceptor-dependent PCA-oxidizing activity of C. portucalensis MBL to that of several other {gamma}-proteobacteria with varying capacities to respire nitrate. We found that PCA oxidation by these strains in a nitrate-dependent manner is decoupled from growth and correlated with their possession of the periplasmic nitrate reductase Nap. We infer that bacterial PCA oxidation is widespread and propose that it may be genetically determined. Notably, oxidizing PCA enhances the rate of nitrate reduction to nitrite by C. portucalensis MBL beyond the stoichiometric exchange of electrons from PCA to nitrate, which we attribute to C. portucalensis MBLs ability to also reduce oxidized PCA, thereby catalyzing a complete PCA redox cycle. This bidirectionality highlights the versatility of PCA as a biological redox agent.

IMPORTANCEPhenazines are increasingly appreciated for their roles in structuring microbial communities. These tricyclic aromatic molecules have been found to regulate gene expression, be toxic, promote antibiotic tolerance, and promote survival under oxygen starvation. In all of these contexts, however, phenazines are studied as electron acceptors. Even if their utility arises primarily from being readily reduced, they need to be oxidized in order to be recycled. While oxygen and ferric iron can oxidize phenazines abiotically, biotic oxidation of phenazines has not been studied previously. We observed bacteria that readily oxidize phenazine-1-carboxylic acid (PCA) in a nitrate-dependent fashion, concomitantly increasing the rate of nitrate reduction to nitrite. Because nitrate is a prevalent terminal electron acceptor in diverse anoxic environments, including soils, and phenazine-producers are widespread, this observation of linked phenazine and nitrogen redox cycling suggests an underappreciated role for redox-active secreted metabolites in the environment.
]]></description>
<dc:creator>Tsypin, L. M.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2021-06-05</dc:date>
<dc:identifier>doi:10.1101/2021.06.04.447179</dc:identifier>
<dc:title><![CDATA[Nitrate reduction stimulates and is stimulated by phenazine-1-carboxylic acid oxidation by Citrobacter portucalensis MBL]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-06-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.06.06.447266v1?rss=1">
<title>
<![CDATA[
Quantitative examination of five stochastic cell-cycle and cell-size control models for Escherichia coli and Bacillus subtilis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.06.06.447266v1?rss=1</link>
<description><![CDATA[
We examine five quantitative models of the cell-cycle and cell-size control in Escherichia coli and Bacillus subtilis that have been proposed over the last decade to explain single-cell experimental data generated with high-throughput methods. After presenting the statistical properties of these models, we test their predictions against experimental data. Based on simple calculations of the defining correlations in each model, we first dismiss the stochastic Helmstetter-Cooper model and the Initiation Adder model, and show that both the Replication Double Adder and the Independent Double Adder model are more consistent with the data than the other models. We then apply a recently proposed statistical analysis method and obtain that the Independent Double Adder model is the most likely model of the cell cycle. By showing that the Replication Double Adder model is fundamentally inconsistent with size convergence by the adder principle, we conclude that the Independent Double Adder model is most consistent with the data and the biology of bacterial cell-cycle and cell-size control. Mechanistically, the Independent Adder Model is equivalent to two biological principles: (i) balanced biosynthesis of the cell-cycle proteins, and (ii) their accumulation to a respective threshold number to trigger initiation and division.
]]></description>
<dc:creator>Le Treut, G.</dc:creator>
<dc:creator>Si, F.</dc:creator>
<dc:creator>Li, D.</dc:creator>
<dc:creator>Jun, S.</dc:creator>
<dc:date>2021-06-06</dc:date>
<dc:identifier>doi:10.1101/2021.06.06.447266</dc:identifier>
<dc:title><![CDATA[Quantitative examination of five stochastic cell-cycle and cell-size control models for Escherichia coli and Bacillus subtilis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-06-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.06.07.447366v1?rss=1">
<title>
<![CDATA[
Natural variation in the irld gene family affects insulin/IGF signaling and starvation resistance 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.06.07.447366v1?rss=1</link>
<description><![CDATA[
Starvation resistance is important to disease and fitness, but the genetic basis of its natural variation is unknown. We developed a synthetic-population (re)sequencing approach using molecular inversion probes (MIP-seq) to measure relative fitness during and after larval starvation in C. elegans. We applied this competitive assay to 100 genetically diverse, sequenced, wild strains, revealing natural variation in starvation resistance. We confirmed that the most starvation-resistant strains survive and recover from starvation better than the most starvation-sensitive strain, MY2147, using standard assays. We performed genome-wide association with the MIP-seq trait data and identified three quantitative trait loci (QTL) for starvation resistance. These QTL contain several members of the Insulin/EGF Receptor-L Domain (irld) family with sequence variation associated with variation in starvation resistance. We used genome editing to show that individual modification of four irld genes increases starvation resistance of MY2147. Modification of irld-39 and irld-52 together increases starvation resistance of the laboratory-reference strain N2. Increased starvation resistance of the irld-39; irld-52 double mutant depends on daf-16/FoxO, and these worms also show increased nuclear localization of DAF-16 during starvation. DAF-16/FoxO is a widely conserved transcriptional effector of insulin/IGF signaling (IIS), and these results suggest that IRLD proteins modify IIS. This work demonstrates efficacy of using MIP-seq to dissect a complex trait, identifies irld genes as natural modifiers of starvation resistance in C. elegans, and suggests that an expanded gene family affects a deeply conserved signaling pathway to alter a fitness-proximal trait.
]]></description>
<dc:creator>Webster, A. K.</dc:creator>
<dc:creator>Chitrakar, R.</dc:creator>
<dc:creator>Powell, M.</dc:creator>
<dc:creator>Chen, J.</dc:creator>
<dc:creator>Fisher, K.</dc:creator>
<dc:creator>Tanny, R.</dc:creator>
<dc:creator>Stevens, L.</dc:creator>
<dc:creator>Evans, K.</dc:creator>
<dc:creator>Antoshechkin, I.</dc:creator>
<dc:creator>Andersen, E. C.</dc:creator>
<dc:creator>Baugh, L. R.</dc:creator>
<dc:date>2021-06-07</dc:date>
<dc:identifier>doi:10.1101/2021.06.07.447366</dc:identifier>
<dc:title><![CDATA[Natural variation in the irld gene family affects insulin/IGF signaling and starvation resistance]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-06-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.06.08.447067v1?rss=1">
<title>
<![CDATA[
Liana optical traits increase tropical forest albedo and reduce ecosystem productivity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.06.08.447067v1?rss=1</link>
<description><![CDATA[
Lianas are a key growth form in tropical forests. Their lack of self-supporting tissues and their vertical position on top of the canopy make them strong competitors of resources. A few pioneer studies have shown that liana optical traits differ on average from those of colocated tree. Those trait discrepancies were hypothesized to be responsible for the competitive advantage of lianas over trees. Yet, in the absence of reliable modelling tools, it is impossible to unravel their impact on the forest energy balance, light competition and on the liana success in Neotropical forests. To bridge this gap, we performed a meta-analysis of the literature to gather all published liana leaf optical spectra, as well as all canopy spectra measured over different levels of liana infestation. We then used a Bayesian data assimilation framework applied to two radiative transfer models (RTMs) covering the leaf and canopy scales to derive tropical tree and liana trait distributions, which finally informed a full dynamic vegetation model. According to the RTMs inversion, lianas grew thinner, more horizontal leaves with lower pigment concentrations. Those traits made the lianas particularly efficient at light interception and completely modified the forest energy balance and its carbon cycle. While forest albedo increased by 14% in the shortwave, light availability was dramatically reduced in the understory (-30% of the PAR radiation) and soil temperature decreased by 0.5{degrees}C. Those liana-specific traits were also responsible for a significant reduction of tree (-19%) and ecosystem (-7%) gross primary productivity (GPP) while lianas benefited from them (their GPP increased by +27%). This study provides a novel mechanistic explanation to the increase in liana abundance, new evidence of the impact of structural parasitism on forest functioning, and paves the way for the evaluation of the large-scale impacts of woody vines on forest biogeochemical cycles.
]]></description>
<dc:creator>Meunier, F.</dc:creator>
<dc:creator>Visser, M. D.</dc:creator>
<dc:creator>Shiklomanov, A.</dc:creator>
<dc:creator>Dietze, M. C.</dc:creator>
<dc:creator>Guzman, J. A.</dc:creator>
<dc:creator>Sanchez-Azofeifa, A.</dc:creator>
<dc:creator>De Deurwaerder, H. P. T.</dc:creator>
<dc:creator>Krishna Moorty, S. M.</dc:creator>
<dc:creator>Schnitzer, S. A.</dc:creator>
<dc:creator>Marvin, D. C.</dc:creator>
<dc:creator>Longo, M.</dc:creator>
<dc:creator>Chang, L.</dc:creator>
<dc:creator>Broadbent, E. N.</dc:creator>
<dc:creator>Zambrano, A. M. A.</dc:creator>
<dc:creator>Muller-Landau, H. C.</dc:creator>
<dc:creator>Detto, M.</dc:creator>
<dc:creator>Verbeeck, H.</dc:creator>
<dc:date>2021-06-09</dc:date>
<dc:identifier>doi:10.1101/2021.06.08.447067</dc:identifier>
<dc:title><![CDATA[Liana optical traits increase tropical forest albedo and reduce ecosystem productivity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-06-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.06.14.448362v1?rss=1">
<title>
<![CDATA[
Evolution of the nitric oxide synthase family in vertebrates and novel insights in gill development 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.06.14.448362v1?rss=1</link>
<description><![CDATA[
Nitric oxide (NO) is an ancestral key signaling molecule essential for life and has enormous versatility in biological systems, including cardiovascular homeostasis, neurotransmission, and immunity. Although our knowledge of nitric oxide synthases (Nos), the enzymes that synthesize NO in vivo, is substantial, the origin of a large and diversified repertoire of nos gene orthologs in fish with respect to tetrapods remains a puzzle. The recent identification of nos3 in the ray-finned fish spotted gar, which was considered lost in the ray-finned fish lineage, changed this perspective. This prompted us to explore nos gene evolution and expression in depth, surveying vertebrate species representing key evolutionary nodes. This study provides noteworthy findings: first, nos2 experienced several lineage-specific gene duplications and losses. Second, nos3 was found to be lost independently in two different teleost lineages, Elopomorpha and Clupeocephala. Third, the expression of at least one nos paralog in the gills of developing shark, bichir, sturgeon, and gar but not in arctic lamprey, suggest that nos expression in this organ likely arose in the last common ancestor of gnathostomes. These results provide a framework for continuing research on nos genes roles, highlighting subfunctionalization and reciprocal loss of function that occurred in different lineages during vertebrate genome duplications.
]]></description>
<dc:creator>Annona, G.</dc:creator>
<dc:creator>Sato, I.</dc:creator>
<dc:creator>Pascual-Anaya, J.</dc:creator>
<dc:creator>Braasch, I.</dc:creator>
<dc:creator>Voss, R.</dc:creator>
<dc:creator>Stundl, J.</dc:creator>
<dc:creator>Soukup, V.</dc:creator>
<dc:creator>Kuratani, S.</dc:creator>
<dc:creator>Postlethwait, J.</dc:creator>
<dc:creator>D'Aniello, S.</dc:creator>
<dc:date>2021-06-14</dc:date>
<dc:identifier>doi:10.1101/2021.06.14.448362</dc:identifier>
<dc:title><![CDATA[Evolution of the nitric oxide synthase family in vertebrates and novel insights in gill development]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-06-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.06.15.448478v1?rss=1">
<title>
<![CDATA[
Active feature selection discovers minimal gene-sets for classifying cell-types and disease states in single-cell mRNA-seq data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.06.15.448478v1?rss=1</link>
<description><![CDATA[
Sequencing costs currently prohibit the application of single-cell mRNA-seq to many biological and clinical analyses. Targeted single-cell mRNA-sequencing reduces sequencing costs by profiling reduced gene sets that capture biological information with a minimal number of genes. Here, we introduce an active learning method (ActiveSVM) that identifies minimal but highly-informative gene sets that enable the identification of cell-types, physiological states, and genetic perturbations in single-cell data using a small number of genes. Our active feature selection procedure generates minimal gene sets from single-cell data through an iterative cell-type classification task where misclassified cells are examined at each round of analysis to identify maximally informative genes through an  active support vector machine (ActiveSVM) classifier. By focusing computational resources on misclassified cells, ActiveSVM scales to analyze data sets with over a million single cells. We demonstrate that ActiveSVM feature selection identifies gene sets that enable 90% cell-type classification accuracy across a variety of data sets including cell atlas and disease characterization data sets. The method generalizes to reveal genes that respond to genetic perturbations and to identify region specific gene expression patterns in spatial transcriptomics data. The discovery of small but highly informative gene sets should enable substantial reductions in the number of measurements necessary for application of single-cell mRNA-seq to clinical tests, therapeutic discovery, and genetic screens.
]]></description>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2021-06-16</dc:date>
<dc:identifier>doi:10.1101/2021.06.15.448478</dc:identifier>
<dc:title><![CDATA[Active feature selection discovers minimal gene-sets for classifying cell-types and disease states in single-cell mRNA-seq data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-06-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.06.21.449295v1?rss=1">
<title>
<![CDATA[
Voltage-driven polyelectrolyte complexation inside a nanopore 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.06.21.449295v1?rss=1</link>
<description><![CDATA[
We have investigated how a pair of oppositely charged macromolecules can be driven by an electric field to form a polyelectrolyte complex inside a nanopore. To observe and isolate an individual complex pair, a model protein nanopore, embedded in artificial phospholipid membrane, allowing compartmentalization (cis/trans) is employed. A polyanion in the cis and a polycation in the trans compartments are subjected to electrophoretic capture by the pore. We find that the measured ionic current across the pore has a distinguishable signature of complex formation, which is different from the signature of the passage of individual molecules through the pore. The ionic current signature allows us to detect the interaction between the two oppositely charged macromolecules and thus, enables us to measure the lifetime of the complex inside the nanopore. After showing that we can isolate a complex pair in the nanopore, we studied the effects of molecular identity on the nature of interaction in different complex pairs. In contrast to the irreversible conductance state of the alpha-hemolysin (HL) channel in the complexation of poly-styrene-sulfonate (PSS) and poly-L-lysine (PLL), a reversible conductance state is observed during complexation between single stranded DNA (ssDNA) and PLL. This suggests that there is a weak interaction between ssDNA and PLL, when compared to the interaction in a PSS-PLL complex. Analysis of the PSS-PLL complexation events and its lifetime inside the nanopore supports a four step-mechanism: (i) The polyanion is captured by the pore, (ii) the polyanion starts threading through the pore. (iii) The polycation is captured, a complex pair is formed in the pore, and the polyanion slides along the polycation. (iv) The complex pair can be pulled through the pore into the trans compartment or it can dissociate. Additionally, we have developed a simple theoretical model, which describes the lifetime of the complex inside the pore. The observed reversible two-state conductance across HL channel during ssDNA-PLL complexation, is described as the binding/unbinding of PLL during the translocation of ssDNA. This enables us to evaluate the apparent rate constants for association/dissociation and equilibrium dissociation constants for the interaction of PLL with ssDNA. This work throws light on the behavior of polyelectrolyte complexes in an electric field and enhances our understanding of the electrical aspects of inter-macromolecular interactions, which plays an extremely important role in the organization of macromolecules in the crowded and confined cellular environment.
]]></description>
<dc:creator>Muthukumar, M.</dc:creator>
<dc:creator>Tripathi, P.</dc:creator>
<dc:creator>Jeon, B.-j.</dc:creator>
<dc:date>2021-06-22</dc:date>
<dc:identifier>doi:10.1101/2021.06.21.449295</dc:identifier>
<dc:title><![CDATA[Voltage-driven polyelectrolyte complexation inside a nanopore]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-06-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.06.22.449412v1?rss=1">
<title>
<![CDATA[
Computational neural network provides naturalistic solution for recovery of finger dexterity after stroke 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.06.22.449412v1?rss=1</link>
<description><![CDATA[
Finger dexterity is a fundamental movement skill of humans and the ability to individuate fingers imparts high motor flexibility. Disruption of dexterity due to brain injury reduces quality of life. Thus, understanding the neurological mechanisms responsible for recovery is critical to effective neurorehabilitation. Two neuronal pathways have been proposed to play crucial roles in finger individuation: the corticospinal tract, originating from primary motor cortex and premotor areas, and the subcortical reticulospinal tract, originating from the reticular formation in the brainstem. Finger individuation in patients with lesions to these pathways may recover. However, it remains an open question how the cortical-reticular network reorganizes and contributes to this recovery following a stroke. We hypothesized that interactive connections between cortical and subcortical neurons reflect dynamics appropriate for generating outgoing commands for finger movement. To test this hypothesis, we developed an Artificial Neural Network (ANN) representing a premotor planning input layer, a cortical layer including excitatory and inhibitory neurons and, a reticular layer that control motoneurons eliciting unilateral flexion of two fingers. The ANN was trained to reproduce "normal" activity of finger individuation and strength. Analysis of the trained ANN revealed that the natural dynamical solution was a near-linear relationship between the force of the instructed and uninstructed finger, resembling individuation patterns in humans. A simulated stroke lesion was then applied to the ANN and the resulting finger dexterity was assessed at multiple stages post stroke. Analysis revealed: (1) increased unintended force produced by uninstructed fingers (i.e., enslaving) and (2) weakening of the force in the instructed finger immediately after stroke, (3) improved finger control during recovery that typically occurs early after stroke, and (4) association of this behavior with increased neural plasticity of the residual neurons, as reflected by strengthening of connectivity weights between premotor and focal cortical excitatory and inhibitory neurons, but reduction in connectivity in shared cortical neurons. Interestingly, the network solution predicted that the reticulospinal pathway also contributed to the improved behavior. Lastly, the ANN also predicts the effect of cortical lesion size on finger individuation. Our model provides a framework by which to understand a number of experimental findings. The model solution suggests that a key mechanism of finger individuation is establishment of an interactive relationship between cortical and subcortical regions, appropriate to produce desired finger movement.
]]></description>
<dc:creator>Kadry, A.</dc:creator>
<dc:creator>Norman, S.</dc:creator>
<dc:creator>Xu, J.</dc:creator>
<dc:creator>Solomonow-Avnon, D.</dc:creator>
<dc:creator>Mawase, F.</dc:creator>
<dc:date>2021-06-22</dc:date>
<dc:identifier>doi:10.1101/2021.06.22.449412</dc:identifier>
<dc:title><![CDATA[Computational neural network provides naturalistic solution for recovery of finger dexterity after stroke]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-06-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.06.25.449955v1?rss=1">
<title>
<![CDATA[
Deep parallel characterization of AAV tropism and AAV-mediated transcriptional changes via single-cell RNA sequencing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.06.25.449955v1?rss=1</link>
<description><![CDATA[
Engineered variants of recombinant adeno-associated viruses (rAAVs) are being developed rapidly to meet the need for gene-therapy delivery vehicles with particular cell-type and tissue tropisms. While high-throughput AAV engineering and selection methods have generated numerous variants, subsequent tropism and response characterization have remained low throughput and lack resolution across the many relevant cell and tissue types. To fully leverage the output of these large screening paradigms across multiple targets, we have developed an experimental and computational single-cell RNA sequencing (scRNA-seq) pipeline for in vivo characterization of barcoded rAAV pools at unprecedented resolution. Using our platform, we have corroborated previously reported viral tropisms and discovered unidentified AAV capsid targeting biases. As expected, we observed that the tropism profile of AAV.CAP-B10 in mice was shifted toward neurons and away from astrocytes when compared with AAV-PHP.eB. Our transcriptomic analysis revealed that this neuronal bias is mainly due to increased targeting efficiency for glutamatergic neurons, which we confirmed by RNA fluorescence in situ hybridization. We further uncovered cell subtype tropisms of AAV variants in vascular and glial cells, such as low transduction of pericytes and Myoc+ astrocytes. Additionally, we have observed cell-type-specific responses to systemic AAV-PHP.eB administration, such as upregulation of genes involved in p53 signaling in endothelial cells three days post-injection, which return to control levels by day twenty-five. Such ability to parallelize the characterization of AAV tropism and simultaneously measure the transcriptional response of transduction will facilitate the advancement of safe and precise gene delivery vehicles.
]]></description>
<dc:creator>Brown, D.</dc:creator>
<dc:creator>Altermatt, M.</dc:creator>
<dc:creator>Dobreva, T.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Wang, A.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2021-06-25</dc:date>
<dc:identifier>doi:10.1101/2021.06.25.449955</dc:identifier>
<dc:title><![CDATA[Deep parallel characterization of AAV tropism and AAV-mediated transcriptional changes via single-cell RNA sequencing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-06-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.01.450787v1?rss=1">
<title>
<![CDATA[
Signaling receptor localization maximizes cellular information acquisition in spatially-structured, natural environments 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.01.450787v1?rss=1</link>
<description><![CDATA[
Cells in natural environments like tissue or soil sense and respond to extracellular ligands with intricately structured and non-monotonic spatial distributions, sculpted by processes such as fluid flow and substrate adhesion. In this work, we show that spatial sensing and navigation can be optimized by adapting the spatial organization of signaling pathways to the spatial structure of the environment. We develop an information-theoretic framework for computing the optimal spatial organization of a sensing system for a given signaling environment. We find that receptor localization maximizes information acquisition in simulated natural contexts, including tissue and soil. Receptor localization extends naturally to produce a dynamic protocol for continuously redistributing signaling receptors, which when implemented using simple feedback, boosts cell navigation efficiency by 30-fold. Broadly, our work shows how cells can maximize the fidelity of information transfer by adapting the spatial organization of signaling molecules to the spatial structure of the environment.
]]></description>
<dc:creator>Wang, Z. J.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2021-07-02</dc:date>
<dc:identifier>doi:10.1101/2021.07.01.450787</dc:identifier>
<dc:title><![CDATA[Signaling receptor localization maximizes cellular information acquisition in spatially-structured, natural environments]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.04.451030v1?rss=1">
<title>
<![CDATA[
Single cell tools for WormBase 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.04.451030v1?rss=1</link>
<description><![CDATA[
We present two web apps for interactively performing common tasks with single cell RNA sequencing data: scdefg for interactive differential expression and wormcells-viz for visualization of gene expression. We made these tools available with public C. elegans datasets curated by WormBase at single-cell.wormbase.org. They can also be readily deployed for use with any other datasets using the source code available at github.com/WormBase/scdefg and at github.com/WormBase/wormcells-viz.
]]></description>
<dc:creator>da Veiga Beltrame, E.</dc:creator>
<dc:creator>Arnaboldi, V.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2021-07-04</dc:date>
<dc:identifier>doi:10.1101/2021.07.04.451030</dc:identifier>
<dc:title><![CDATA[Single cell tools for WormBase]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.06.451241v1?rss=1">
<title>
<![CDATA[
UVC inactivation of pathogenic samples suitable for cryoEM analysis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.06.451241v1?rss=1</link>
<description><![CDATA[
Cryo-electron microscopy has become an essential tool to understand structure and function of biological samples, from individual proteins to whole cells. Especially for pathogens, such as disease-causing bacteria and viruses, insights gained by cryo-EM can aid in developing cures. However, due to the biosafety restrictions of human pathogens, samples are often treated by chemical fixation to render the pathogen inert, affecting the delicate ultrastructure of the sample. Alternatively, researchers use in vitro or ex vivo models, which are non-pathogenic but lack the complexity of the pathogen of interest. Here we show that ultraviolet-C (UVC) radiation at cryogenic temperatures can be used to eliminate or dramatically reduce the infectivity of two model organisms, a pathogenic bacterium (Vibrio cholerae) and a virus-like particle (the ICP1 bacteriophage). We show no discernable structural impact of this treatment of either sample using two cryo-EM methods: cryo-electron tomography (cryo-ET) followed by sub-tomogram averaging (STA), and single particle analysis (SPA). Additionally, we applied the UVC irradiation to the protein apoferritin (ApoF), which is a widely used test sample for high resolution SPA studies. The UVC-treated ApoF sample resulted in a 2.1 [A] structure that did not reveal any discernable structural damage. Together, these results show that the UVC irradiation dose that effectively inactivates cryo-EM samples does not negatively impact their structure. This research demonstrates that UVC treatment is an effective and inexpensive addition to the cryo-EM sample preparation toolbox.
]]></description>
<dc:creator>Depelteau, J. S.</dc:creator>
<dc:creator>Renault, L.</dc:creator>
<dc:creator>Althof, N.</dc:creator>
<dc:creator>Cassidy, C. K.</dc:creator>
<dc:creator>Mendonca, L. M.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Resch, G. P.</dc:creator>
<dc:creator>Briegel, A.</dc:creator>
<dc:date>2021-07-06</dc:date>
<dc:identifier>doi:10.1101/2021.07.06.451241</dc:identifier>
<dc:title><![CDATA[UVC inactivation of pathogenic samples suitable for cryoEM analysis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.08.450798v1?rss=1">
<title>
<![CDATA[
FANCD2 directly inhibits DNA2 nuclease at stalled replication forks and acts as a RAD51 mediator in strand exchange 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.08.450798v1?rss=1</link>
<description><![CDATA[
FANCD2 protein, a key coordinator and effector of the interstrand crosslink repair pathway, is also required to prevent excessive nascent strand degradation at hydroxyurea-induced stalled forks. The RAD51 recombinase has also been implicated in regulation of resection at stalled replication forks. The mechanistic contributions of these proteins to fork protection are not well understood. Here, we used purified FANCD2 and RAD51 to study how each protein regulates DNA resection at stalled forks. We showed that FANCD2 inhibits fork degradation in two ways: 1) the N-terminal domain of FANCD2 inhibits DNA2 nuclease activity by directly binding to DNA2. 2) independent of dimerization with FANCI, FANCD2 itself stabilizes RAD51 filaments to inhibit multiple nucleases, including DNA2, MRE11, and EXO1. Unexpectedly, we uncovered a new FANCD2 function: by stabilizing RAD51 filaments, FANCD2 acts as a "RAD51 modulator" to stimulate the strand exchange activity of RAD51. Our work biochemically explains non-canonical mechanisms by which FANCD2 and RAD51 protect stalled forks. We propose a model in which the strand exchange activity of FANCD2 provides a simple molecular explanation for genetic interactions between FANCD2 and the BRCA2 mediator in the FA/BRCA pathway of fork protection
]]></description>
<dc:creator>Liu, W.</dc:creator>
<dc:creator>Roubal, I.</dc:creator>
<dc:creator>Polaczek, P.</dc:creator>
<dc:creator>Meng, Y.</dc:creator>
<dc:creator>Choe, W.-c.</dc:creator>
<dc:creator>Caron, M. C.</dc:creator>
<dc:creator>Sedgeman, C. A.</dc:creator>
<dc:creator>Xi, Y.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Wu, Q.</dc:creator>
<dc:creator>Zheng, L.</dc:creator>
<dc:creator>Masson, J. Y.</dc:creator>
<dc:creator>Shen, B.</dc:creator>
<dc:creator>Campbell, J. L.</dc:creator>
<dc:date>2021-07-09</dc:date>
<dc:identifier>doi:10.1101/2021.07.08.450798</dc:identifier>
<dc:title><![CDATA[FANCD2 directly inhibits DNA2 nuclease at stalled replication forks and acts as a RAD51 mediator in strand exchange]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.08.451594v1?rss=1">
<title>
<![CDATA[
The geometry of domain-general performance monitoring representations in the human medial frontal cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.08.451594v1?rss=1</link>
<description><![CDATA[
Controlling behavior to flexibly achieve desired goals depends on the ability to monitor ones own performance. It is unknown how performance monitoring can be both flexible to support different tasks and specialized to perform well on each. We recorded single neurons in the human medial frontal cortex while subjects performed two tasks that involve three types of cognitive conflict. Neurons encoding predicted conflict, conflict, and error in one or both tasks were intermixed, forming a representational geometry that simultaneously allowed task specialization and generalization. Neurons encoding conflict retrospectively served to update internal estimates of control demand. Population representations of conflict were compositional. These findings reveal how representations of evaluative signals can be both abstract and task-specific and suggest a neuronal mechanism for estimating control demand.
]]></description>
<dc:creator>Fu, Z.</dc:creator>
<dc:creator>Beam, D.</dc:creator>
<dc:creator>Chung, J. M.</dc:creator>
<dc:creator>Reed, C. M.</dc:creator>
<dc:creator>Mamelak, A. N.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:creator>Rutishauser, U.</dc:creator>
<dc:date>2021-07-08</dc:date>
<dc:identifier>doi:10.1101/2021.07.08.451594</dc:identifier>
<dc:title><![CDATA[The geometry of domain-general performance monitoring representations in the human medial frontal cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.09.451694v1?rss=1">
<title>
<![CDATA[
Atp13a5 Marker Reveals Pericytes of The Central Nervous System in Mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.09.451694v1?rss=1</link>
<description><![CDATA[
Perivascular mural cells including vascular smooth cells (VSMCs) and pericytes are integral components of the vascular system. In the central nervous system (CNS), pericytes are also known as the guardian of the blood-brain barrier, blood-spinal cord barrier and blood-retinal barrier, and play key roles in maintaining cerebrovascular and neuronal functions. However, the functional difference between CNS and peripheral pericytes has not been resolved at the genetic and molecular levels. Hence, the generation of reliable CNS pericyte-specific models and genetic tools remains very challenging. Here, we report a new CNS pericyte marker in mice. This cation-transporting ATPase 13A5 (Atp13a5) marker is highly specific to the pericytes in brain, spinal cord and retina. We generated a transgenic model with a knock-in tdTomato reporter and Cre recombinase. The tdTomato reporter reliably labels the CNS pericytes, but not found in any other CNS cell types including closely related VSMCs, or in peripheral organs. More importantly, Atp13a5 is turned on at embryonic day E15, suggesting brain pericytes are shaped by the developing neural environment. We hope that the new tools will allow us to further explore the heterogeneity of pericytes and achieve a better understanding of CNS pericytes in health and diseases.
]]></description>
<dc:creator>Guo, X.</dc:creator>
<dc:creator>Ge, T.</dc:creator>
<dc:creator>Xia, S.</dc:creator>
<dc:creator>Wu, H.</dc:creator>
<dc:creator>Colt, M.</dc:creator>
<dc:creator>Xie, X.</dc:creator>
<dc:creator>Zhang, B.</dc:creator>
<dc:creator>Zeng, J.</dc:creator>
<dc:creator>Chen, J.-F.</dc:creator>
<dc:creator>Zhu, D.</dc:creator>
<dc:creator>Montagne, A.</dc:creator>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>Zhao, Z.</dc:creator>
<dc:date>2021-07-10</dc:date>
<dc:identifier>doi:10.1101/2021.07.09.451694</dc:identifier>
<dc:title><![CDATA[Atp13a5 Marker Reveals Pericytes of The Central Nervous System in Mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.13.452161v1?rss=1">
<title>
<![CDATA[
In situ imaging of bacterial membrane projections and associated protein complexes using electron cryo-tomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.13.452161v1?rss=1</link>
<description><![CDATA[
The ability to produce membrane projections in the form of tubular membrane extensions (MEs) and membrane vesicles (MVs) is a widespread phenomenon among bacteria. Despite this, our knowledge of the ultrastructure of these extensions and their associated protein complexes remains limited. Here, we surveyed the ultrastructure and formation of MEs and MVs, and their associated protein complexes, in tens of thousands of electron cryo-tomograms of [~] 90 bacterial species that we have collected for various projects over the past 15 years (Jensen lab database), in addition to data generated in the Briegel lab. We identified MEs and MVs in 13 species and classified several major ultrastructures: 1) tubes with a uniform diameter (with or without an internal scaffold), 2) tubes with irregular diameter, 3) tubes with a vesicular dilation at their tip, 4) pearling tubes, 5) connected chains of vesicles (with or without neck-like connectors), 6) budding vesicles and nanopods. We also identified several protein complexes associated with these MEs and MVs which were distributed either randomly or exclusively at the tip. These complexes include a secretin-like structure and a novel crown-shaped structure observed primarily in vesicles from lysed cells. In total, this work helps to characterize the diversity of bacterial membrane projections and lays the groundwork for future research in this field.
]]></description>
<dc:creator>Kaplan, M.</dc:creator>
<dc:creator>Chreifi, G.</dc:creator>
<dc:creator>Metskas, L. A.</dc:creator>
<dc:creator>Liedtke, J.</dc:creator>
<dc:creator>Wood, C. R.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>NICOLAS, W. J.</dc:creator>
<dc:creator>Subramanian, P.</dc:creator>
<dc:creator>Zacharoff, L. A.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Chang, Y.-W.</dc:creator>
<dc:creator>Beeby, M.</dc:creator>
<dc:creator>Dobro, M.</dc:creator>
<dc:creator>Mcbride, M. J.</dc:creator>
<dc:creator>Briegel, A.</dc:creator>
<dc:creator>Shaffer, C.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2021-07-13</dc:date>
<dc:identifier>doi:10.1101/2021.07.13.452161</dc:identifier>
<dc:title><![CDATA[In situ imaging of bacterial membrane projections and associated protein complexes using electron cryo-tomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.24.453587v1?rss=1">
<title>
<![CDATA[
Evolution of a chordate-specific mechanism for myoblast fusion 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.24.453587v1?rss=1</link>
<description><![CDATA[
The size of an animal is determined by the size of its musculoskeletal system. Myoblast fusion is an innovative mechanism that allows for multinucleated muscle fibers to compound the size and strength of individual mononucleated cells. However, the evolutionary history of the control mechanism underlying this important process is currently unknown. The phylum Chordata hosts closely related groups that span distinct myoblast fusion states: no fusion in cephalochordates, restricted fusion and multinucleation in tunicates, and extensive, obligatory fusion in vertebrates. To elucidate how these differences may have evolved, we studied the evolutionary origins and function of membrane-coalescing agents Myomaker and Myomixer in various groups of chordates. Here we report that Myomaker likely arose through gene duplication in the last common ancestor of tunicates and vertebrates, while Myomixer appears to have evolved de novo in early vertebrates. Functional tests revealed an unexpectedly complex evolutionary history of myoblast fusion in chordates. A pre-vertebrate phase of muscle multinucleation driven by Myomaker was followed by the later emergence of Myomixer that enables the highly efficient fusion system of vertebrates. Thus, our findings reveal the evolutionary origins of chordate-specific fusogens and illustrate how new genes can shape the emergence of novel morphogenetic traits and mechanisms.
]]></description>
<dc:creator>Zhang, H.</dc:creator>
<dc:creator>Shang, R.</dc:creator>
<dc:creator>Kim, K.</dc:creator>
<dc:creator>Zheng, W.</dc:creator>
<dc:creator>Johnson, C. J.</dc:creator>
<dc:creator>Sun, L.</dc:creator>
<dc:creator>Niu, X.</dc:creator>
<dc:creator>Liu, L.</dc:creator>
<dc:creator>Uyeno, T. A.</dc:creator>
<dc:creator>Zhou, J.</dc:creator>
<dc:creator>Liu, L.</dc:creator>
<dc:creator>Pei, J.</dc:creator>
<dc:creator>Fissette, S. D.</dc:creator>
<dc:creator>Green, S. A.</dc:creator>
<dc:creator>Samudra, S. P.</dc:creator>
<dc:creator>Wen, J.</dc:creator>
<dc:creator>Zhang, J.</dc:creator>
<dc:creator>Eggenschwiler, J.</dc:creator>
<dc:creator>Menke, D.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>Grishin, N. V.</dc:creator>
<dc:creator>Li, W.</dc:creator>
<dc:creator>Ye, K.</dc:creator>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Stolfi, A.</dc:creator>
<dc:creator>Bi, P.</dc:creator>
<dc:date>2021-07-25</dc:date>
<dc:identifier>doi:10.1101/2021.07.24.453587</dc:identifier>
<dc:title><![CDATA[Evolution of a chordate-specific mechanism for myoblast fusion]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.26.453904v1?rss=1">
<title>
<![CDATA[
Engineering Viral Vectors for Acoustically Targeted Gene Delivery 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.26.453904v1?rss=1</link>
<description><![CDATA[
Targeted gene delivery to the brain is a critical tool for neuroscience research and has significant potential to treat human disease. However, the site-specific delivery of common gene vectors such as adeno-associated viruses (AAVs) is typically performed via invasive injections, limiting their scope of research and clinical applications. Alternatively, focused ultrasound blood-brain-barrier opening (FUS-BBBO), performed noninvasively, enables the site-specific entry of AAVs into the brain from systemic circulation. However, when used in conjunction with natural AAV serotypes, this approach has limited transduction efficiency, requires ultrasound parameters close to tissue damage limits, and results in undesirable transduction of peripheral organs. Here, we use high throughput in vivo selection to engineer new AAV vectors specifically designed for local neuronal transduction at the site of FUS-BBBO. The resulting vectors substantially enhance ultrasound-targeted gene delivery and neuronal tropism while reducing peripheral transduction, providing a more than ten-fold improvement in targeting specificity. In addition to enhancing the only known approach to noninvasively target gene delivery to specific brain regions, these results establish the ability of AAV vectors to be evolved for specific physical delivery mechanisms.
]]></description>
<dc:creator>Li, H.</dc:creator>
<dc:creator>Heath, J. E.</dc:creator>
<dc:creator>Trippett, J. S.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Szablowski, J. O.</dc:creator>
<dc:date>2021-07-27</dc:date>
<dc:identifier>doi:10.1101/2021.07.26.453904</dc:identifier>
<dc:title><![CDATA[Engineering Viral Vectors for Acoustically Targeted Gene Delivery]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.29.454365v1?rss=1">
<title>
<![CDATA[
The HMCES DNA-protein cross-link functions as a constitutive DNA repair intermediate 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.29.454365v1?rss=1</link>
<description><![CDATA[
The HMCES protein forms a covalent DNA-protein cross-link (DPC) with abasic (AP) sites in ssDNA, and the resulting HMCES-DPC is thought to suppress double-strand break formation in S phase. However, the dynamics of HMCES cross-linking and whether any DNA repair pathways normally include an HMCES-DPC intermediate remain unknown. Here, we show that an HMCES-DPC forms efficiently on the AP site generated during replication-coupled DNA interstrand cross-link (ICL) repair. We use this system to show that HMCES cross-links form on DNA after the replicative CMG helicase has passed over the AP site, and that HMCES is subsequently removed by the SPRTN protease. The HMCES-DPC suppresses DSB formation, slows translesion synthesis (TLS) past the AP site, and introduces a bias for insertion of deoxyguanosine opposite the AP site. These data show that HMCES-DPCs can form as constitutive intermediates in replication-coupled repair, and they suggest a general model of how HMCES protects AP sites during DNA replication.
]]></description>
<dc:creator>Semlow, D. R.</dc:creator>
<dc:creator>MacKrell, V. A.</dc:creator>
<dc:creator>Walter, J.</dc:creator>
<dc:date>2021-07-29</dc:date>
<dc:identifier>doi:10.1101/2021.07.29.454365</dc:identifier>
<dc:title><![CDATA[The HMCES DNA-protein cross-link functions as a constitutive DNA repair intermediate]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.30.454514v1?rss=1">
<title>
<![CDATA[
Length Biases in Single-Cell RNA Sequencing of pre-mRNA 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.30.454514v1?rss=1</link>
<description><![CDATA[
Single-molecule pre-mRNA and mRNA sequencing data can be modeled and analyzed using the Markov chain formalism to yield genome-wide insights into transcription. However, quantitative inference with such data requires careful assessment and understanding of noise sources. We find that long pre-mRNA transcripts are over-represented in sequencing data, and explore the mechanistic implications. A biological explanation for this phenomenon within our modeling framework requires unrealistic transcriptional parameters, leading us to posit a length-based model of capture bias. We provide solutions for this model, and use them to find concordant and mechanistically plausible parameter trends across data from multiple single-cell RNA-seq experiments in several species.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2021-07-31</dc:date>
<dc:identifier>doi:10.1101/2021.07.30.454514</dc:identifier>
<dc:title><![CDATA[Length Biases in Single-Cell RNA Sequencing of pre-mRNA]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.02.454472v1?rss=1">
<title>
<![CDATA[
Microbial community of recently discovered Auka vent field sheds light on vent biogeography and evolutionary history of thermophily 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.02.454472v1?rss=1</link>
<description><![CDATA[
Hydrothermal vents have been key to our understanding of the limits of life, and the metabolic and phylogenetic diversity of thermophilic organisms. Here we used environmental metagenomics combined with analysis of physico-chemical data and 16S rRNA amplicons to characterize the diversity, temperature optima, and biogeographic distribution of sediment-hosted microorganisms at the recently discovered Auka vents in the Gulf of California, the deepest known hydrothermal vent field in the Pacific Ocean. We recovered 325 metagenome assembled genomes (MAGs) representing 54 phyla, over 1/3 of the currently known phylum diversity, showing the microbial community in Auka hydrothermal sediments is highly diverse. Large scale 16S rRNA amplicon screening of 227 sediment samples across the vent field indicates that the MAGs are largely representative of the microbial community. Metabolic reconstruction of a vent-specific, deeply branching clade within the Desulfobacterota (Tharpobacteria) suggests these organisms metabolize sulfur using novel octaheme cytochrome-c proteins related to hydroxylamine oxidoreductase. Community-wide comparison of the average nucleotide identity of the Auka MAGs with MAGs from the Guaymas Basin vent field, found 400 km to the Northwest, revealed a remarkable 20% species-level overlap between vent sites, suggestive of long-distance species transfer and sediment colonization. An adapted version of a recently developed model for predicting optimal growth temperature to the Auka and Guaymas MAGs indicates several of these uncultured microorganisms could grow at temperatures exceeding the currently known upper limit of life. Extending this analysis to reference data shows that thermophily is a trait that has evolved frequently among Bacteria and Archaea. Combined, our results show that Auka vent field offers new perspectives on our understanding of hydrothermal vent microbiology.
]]></description>
<dc:creator>Speth, D. R.</dc:creator>
<dc:creator>Yu, F. B.</dc:creator>
<dc:creator>Connon, S. A.</dc:creator>
<dc:creator>Lim, S.</dc:creator>
<dc:creator>Magyar, J. S.</dc:creator>
<dc:creator>Pena, M. E.</dc:creator>
<dc:creator>Quake, S. R.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2021-08-02</dc:date>
<dc:identifier>doi:10.1101/2021.08.02.454472</dc:identifier>
<dc:title><![CDATA[Microbial community of recently discovered Auka vent field sheds light on vent biogeography and evolutionary history of thermophily]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.03.453128v1?rss=1">
<title>
<![CDATA[
The kpc-1 (furin) 3'UTR promotes dendritic transport and local translation of mRNAs to regulate dendrite branching and self-avoidance of a nociceptive neuron 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.03.453128v1?rss=1</link>
<description><![CDATA[
A recently reported Schizophrenia-associated genetic variant in the 3UTR of the human furin gene, a homolog of C. elegans kpc-1, highlights an important role of the furin 3UTR in neuronal development(1). We isolate three kpc-1 mutants that display abnormal dendrite arborization in PVD neurons and defective male mating behaviors. We show that the kpc-1 3UTR participates in dendrite branching and self-avoidance. The kpc-1 3UTR facilitates mRNA localization to branching points and contact points between sibling dendrites and promotes local protein synthesis. We identify a secondary structural motif in the kpc-1 3UTR required for dendrite self-avoidance. Animals with dma-1 receptor over-expression exhibit similar dendrite branching and self-avoidance defects that are suppressed with kpc-1 over-expression. Our results support a model in which KPC-1 proteins are synthesized at branching points and contact points to locally down-regulate DMA-1 receptors to promote dendrite branching and self-avoidance of a mechanosensory neuron important for male courtship.
]]></description>
<dc:creator>Zou, Y.</dc:creator>
<dc:creator>Shih, M.</dc:creator>
<dc:creator>Chiu, H.</dc:creator>
<dc:creator>Ferreira, T.</dc:creator>
<dc:creator>Suzuki, N.</dc:creator>
<dc:creator>Zou, W.</dc:creator>
<dc:creator>Chuang, C.-F.</dc:creator>
<dc:creator>Chang, C.</dc:creator>
<dc:date>2021-08-05</dc:date>
<dc:identifier>doi:10.1101/2021.08.03.453128</dc:identifier>
<dc:title><![CDATA[The kpc-1 (furin) 3'UTR promotes dendritic transport and local translation of mRNAs to regulate dendrite branching and self-avoidance of a nociceptive neuron]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.05.455281v1?rss=1">
<title>
<![CDATA[
A population of descending neurons that regulate the flight motor of Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.05.455281v1?rss=1</link>
<description><![CDATA[
Like many insect species, Drosophila melanogaster are capable of maintaining a stable flight trajectory for periods lasting up to several hours(1, 2). Because aerodynamic torque is roughly proportional to the fifth power of wing length(3), even small asymmetries in wing size require the maintenance of subtle bilateral differences in flapping motion to maintain a stable path. Flies can even fly straight after losing half of a wing, a feat they accomplish via very large, sustained kinematic changes to the both damaged and intact wings(4). Thus, the neural network responsible for stable flight must be capable of sustaining fine-scaled control over wing motion across a large dynamic range. In this paper, we describe an unusual type of descending neurons (DNg02) that project directly from visual output regions of the brain to the dorsal flight neuropil of the ventral nerve cord. Unlike most descending neurons, which exist as single bilateral pairs with unique morphology, there is a population of at least 15 DNg02 cell pairs with nearly identical shape. By optogenetically activating different numbers of DNg02 cells, we demonstrate that these neurons regulate wingbeat amplitude over a wide dynamic range via a population code. Using 2-photon functional imaging, we show that DNg02 cells are responsive to visual motion during flight in a manner that would make them well suited to continuously regulate bilateral changes in wing kinematics. Collectively, we have identified a critical set of DNs that provide the sensitivity and dynamic range required for flight control.
]]></description>
<dc:creator>Namiki, S.</dc:creator>
<dc:creator>Ros, I. G.</dc:creator>
<dc:creator>Morrow, C.</dc:creator>
<dc:creator>Rowell, W. J.</dc:creator>
<dc:creator>Card, G. M.</dc:creator>
<dc:creator>Korff, W.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:date>2021-08-06</dc:date>
<dc:identifier>doi:10.1101/2021.08.05.455281</dc:identifier>
<dc:title><![CDATA[A population of descending neurons that regulate the flight motor of Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.06.455469v1?rss=1">
<title>
<![CDATA[
Recombinant NAGLU-IGF2 prevents physical and neurological disease and improves survival in Sanfilippo B syndrome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.06.455469v1?rss=1</link>
<description><![CDATA[
Recombinant human alpha-N-acetylglucosaminidase-insulin-like growth factor-2 (rhNAGLU-IGF2) is an investigational enzyme replacement therapy for Sanfilippo B, a lysosomal storage disease. Because recombinant human NAGLU (rhNAGLU) is poorly mannose 6-phosphorylated, we generated a fusion protein of NAGLU with IGF2 to permit its binding to the cation-independent mannose 6-phosphate receptor. We previously administered rhNAGLU-IGF2 intracerebroventricularly to Sanfilippo B mice, and demonstrated therapeutic restoration of NAGLU, normalization of lysosomal storage, and improvement in markers of neurodegeneration and inflammation. Here, we studied repeated intracerebroventricular rhNAGLU-IGF2 delivery in both murine and canine Sanfilippo B to determine potential effects on their behavioral phenotypes and survival. Treated mice showed improvement in disease markers such as heparan sulfate glycosaminoglycans, beta-hexosaminidase, microglial activation, and lysosomal-associated membrane protein-1. Sanfilippo B mice treated with rhNAGLU-IGF2 displayed partial normalization of their stretch attend postures, a defined fear pose in mice (p<0.001). We found an improved rotarod performance in Sanfilippo B mice treated with rhNAGLU-IGF2 compared to vehicle-treated Sanfilippo B mice (p=0.002). We also found a 61% increase in survival in Sanfilippo B mice treated with rhNAGLU-IGF2 (mean 53w, median 48w) compared to vehicle-treated Sanfilippo B mice (mean 33w, median 37w; p<0.001). In canine Sanfilippo B, we found that rhNAGLU-IGF2 administered into cerebrospinal fluid normalized HS and beta-hexosaminidase activity in gray and white matter brain regions. Proteomic analysis of cerebral cortex showed restoration of protein expression levels in pathways relevant to cognitive, synaptic, and lysosomal functions. These data suggest that treatment with rhNAGLU-IGF2 may improve the phenotype of Sanfilippo B disease.
]]></description>
<dc:creator>Le, S. Q.</dc:creator>
<dc:creator>Kan, S.-h.</dc:creator>
<dc:creator>Nunez, M.</dc:creator>
<dc:creator>Dearborn, J.</dc:creator>
<dc:creator>Wang, F.</dc:creator>
<dc:creator>LI, S.</dc:creator>
<dc:creator>Snella, L.</dc:creator>
<dc:creator>Jens, J. K.</dc:creator>
<dc:creator>Valentine, B. N.</dc:creator>
<dc:creator>Nelvagal, H. R.</dc:creator>
<dc:creator>Sorensen, A.</dc:creator>
<dc:creator>Cooper, J. D.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Ellinwood, N. M.</dc:creator>
<dc:creator>Smith, J. D.</dc:creator>
<dc:creator>Sands, M. S.</dc:creator>
<dc:creator>Dickson, P.</dc:creator>
<dc:date>2021-08-08</dc:date>
<dc:identifier>doi:10.1101/2021.08.06.455469</dc:identifier>
<dc:title><![CDATA[Recombinant NAGLU-IGF2 prevents physical and neurological disease and improves survival in Sanfilippo B syndrome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.08.455573v1?rss=1">
<title>
<![CDATA[
Segregation of neural crest specific lineage trajectories from a heterogeneous neural plate border territory only emerges at neurulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.08.455573v1?rss=1</link>
<description><![CDATA[
The epiblast of vertebrate embryos is comprised of neural and non-neural ectoderm, with the border territory at their intersection harbouring neural crest and cranial placode progenitors. Here we profile avian epiblast cells as a function of time using single-cell RNA-seq to define transcriptional changes in the emerging  neural plate border. The results reveal gradual establishment of heterogeneous neural plate border signatures, including novel genes that we validate by fluorescent in situ hybridisation. Developmental trajectory analysis shows that segregation of neural plate border lineages only commences at early neurulation, rather than at gastrulation as previously predicted. We find that cells expressing the prospective neural crest marker Pax7 contribute to multiple lineages, and a subset of premigratory neural crest cells shares a transcriptional signature with their border precursors. Together, our results suggest that cells at the neural plate border remain heterogeneous until early neurulation, at which time progenitors become progressively allocated toward defined lineages.
]]></description>
<dc:creator>Williams, R.</dc:creator>
<dc:creator>Lukoseviciute, M.</dc:creator>
<dc:creator>Sauka-Spengler, T.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:date>2021-08-08</dc:date>
<dc:identifier>doi:10.1101/2021.08.08.455573</dc:identifier>
<dc:title><![CDATA[Segregation of neural crest specific lineage trajectories from a heterogeneous neural plate border territory only emerges at neurulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.12.456124v1?rss=1">
<title>
<![CDATA[
Gut bacteria regulate the pathogenesis of Huntington's disease in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.12.456124v1?rss=1</link>
<description><![CDATA[
Changes in the composition of gut microbiota are implicated in the pathogenesis of several neurodegenerative disorders. Here, we investigated whether gut bacteria affect the progression of Huntingtons disease (HD) in transgenic Drosophila melanogaster (fruit fly) models expressing human full-length or N-terminal fragments of mutant huntingtin (HTT) protein, here referred to as HD flies. We find that elimination of commensal gut bacteria by antibiotics reduces the aggregation of amyloidogenic N-terminal fragments of HTT and delays the development of motor defects. Conversely, colonization of HD flies with Escherichia coli (E. coli), a known pathobiont of human gut with links to neurodegeneration, accelerates HTT aggregation, aggravates immobility and shortens lifespan. Similar to antibiotics, treatment of HD flies with small compounds such as luteolin, a flavone, or crocin a beta-carotenoid, ameliorates disease phenotypes and promotes survival. Crocin prevents colonization of E. coli in the gut and alters the abundance of commensal bacteria, which may be linked to its protective effects. The opposing effects of E. coli and crocin on HTT aggregation, motor defects and survival in transgenic Drosophila models support the involvement of gut-brain networks in the pathogenesis of HD.
]]></description>
<dc:creator>Chongtham, A.</dc:creator>
<dc:creator>Yoo, J. H.</dc:creator>
<dc:creator>Chin, T. M.</dc:creator>
<dc:creator>Akingbesote, N. D.</dc:creator>
<dc:creator>Huda, A.</dc:creator>
<dc:creator>Khoshnan, A.</dc:creator>
<dc:date>2021-08-13</dc:date>
<dc:identifier>doi:10.1101/2021.08.12.456124</dc:identifier>
<dc:title><![CDATA[Gut bacteria regulate the pathogenesis of Huntington's disease in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.15.456406v1?rss=1">
<title>
<![CDATA[
Optimal dynamic incentive scheduling for Hawk-Dove evolutionary games 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.15.456406v1?rss=1</link>
<description><![CDATA[
The Hawk-Dove mathematical game offers a paradigm of the trade-offs associated with aggressive and passive behaviors. When two (or more) populations of players (animals, insect populations, countries in military conflict, economic competitors, microbial communities, populations of co-evolving tumor cells, or reinforcement learners adopting different strategies) compete, their success or failure can be measured by their frequency in the population (successful behavior is reinforced, unsuccessful behavior is not), and the system is governed by the replicator dynamical system. We develop a time-dependent optimal-adaptive control theory for this nonlinear dynamical system in which the payoffs of the Hawk-Dove payoff matrix are dynamically altered (dynamic incentives) to produce (bang-bang) control schedules that (i) maximize the aggressive population at the end of time T, and (ii) minimize the aggressive population at the end of time T. These two distinct time-dependent strategies produce upper and lower bounds on the outcomes from all strategies since they represent two extremizers of the cost function using the Pontryagin maximum (minimum) principle. We extend the results forward to times nT (n = 1, ..., 5) in an adaptive way that uses the optimal value at the end of time nT to produce the new schedule for time (n + 1)T. Two special schedules and initial conditions are identified that produce absolute maximizers and minimizers over an arbitrary number of cycles for 0 [&le;] T [&le;] 3. For T > 3, our optimum schedules can drive either population to extinction or fixation. The method described can be used to produce optimal dynamic incentive schedules for many different applications in which the 2 x 2 replicator dynamics is used as a governing model.
]]></description>
<dc:creator>Stuckey, K.</dc:creator>
<dc:creator>Dua, R.</dc:creator>
<dc:creator>Ma, Y.</dc:creator>
<dc:creator>Parker, J.</dc:creator>
<dc:creator>Newton, P. K.</dc:creator>
<dc:date>2021-08-15</dc:date>
<dc:identifier>doi:10.1101/2021.08.15.456406</dc:identifier>
<dc:title><![CDATA[Optimal dynamic incentive scheduling for Hawk-Dove evolutionary games]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.16.456551v1?rss=1">
<title>
<![CDATA[
Tuning levels of low-complexity domain interactions to modulate endogenous oncogenic transcription 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.16.456551v1?rss=1</link>
<description><![CDATA[
Gene activation by mammalian transcription factors (TFs) requires dynamic, multivalent, and selective interactions of their intrinsically disordered low-complexity domains (LCDs), but how such interactions mediate transcription remains unclear. It has been proposed that extensive LCD-LCD interactions culminating in liquid-liquid phase separation (LLPS) of TFs is the dominant mechanism underlying transactivation. Here, we investigated how tuning the amount and localization of LCD-LCD interactions in vivo affects transcription of endogenous human genes. Quantitative single-cell and single-molecule imaging reveals that the oncogenic TF EWS/FLI1 requires a finely tuned range of LCD-LCD interactions to efficiently activate target genes. Modest or more dramatic increases in LCD-LCD interactions toward putative LLPS repress EWS/FLI1-driven transcription in patient cells. Likewise, ectopically creating LCD-LCD interactions to sequester EWS/FLI1 into a bona fide LLPS compartment, the nucleolus, inhibits EWS/FLI1-driven transcription and oncogenic transformation. Our findings reveal fundamental principles underlying LCD-mediated transcription and suggest mislocalizing specific LCD-LCD interactions as a novel therapeutic strategy for targeting disease-causing TFs.
]]></description>
<dc:creator>Chong, S.</dc:creator>
<dc:creator>Graham, T. G. W.</dc:creator>
<dc:creator>Dugast-Darzacq, C.</dc:creator>
<dc:creator>Dailey, G. M.</dc:creator>
<dc:creator>Darzacq, X.</dc:creator>
<dc:creator>Tjian, R.</dc:creator>
<dc:date>2021-08-17</dc:date>
<dc:identifier>doi:10.1101/2021.08.16.456551</dc:identifier>
<dc:title><![CDATA[Tuning levels of low-complexity domain interactions to modulate endogenous oncogenic transcription]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.17.456617v1?rss=1">
<title>
<![CDATA[
Distinct neural circuits establish the same chemosensory behavior in C. elegans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.17.456617v1?rss=1</link>
<description><![CDATA[
Animals frequently exhibit the same behavior under different environmental or physiological conditions. To what extent these behaviors are generated by similar vs. distinct mechanisms is unclear. Moreover, the circumstances under which divergent neural mechanisms establish the same behavior, and the molecular signals that regulate the same behavior across conditions, are poorly understood. We show that in C. elegans, distinct neural mechanisms mediate the same chemosensory behavior at two different life stages. Both dauer larvae and starved adults are attracted to carbon dioxide (CO2), but CO2 attraction is mediated by distinct sets of interneurons at the two life stages. Some interneurons mediate CO2 response only in dauers, some show CO2-evoked activity in adults and dauers but contribute to CO2 response only in adults, and some show CO2-evoked activity that opposes CO2 attraction in adults but promotes CO2 attraction in dauers. We also identify a novel role for insulin signaling in establishing life-stage-specific CO2 responses by modulating interneuron activity. Further, we show that a combinatorial code of both shared and life-stage-specific molecular signals regulate CO2 attraction. Our results identify a mechanism by which the same chemosensory behavior can be generated by distinct neural circuits, revealing an unexpected complexity to chemosensory processing.
]]></description>
<dc:creator>Banerjee, N.</dc:creator>
<dc:creator>Shih, P.-Y.</dc:creator>
<dc:creator>Rojas Palato, E. J.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Hallem, E.</dc:creator>
<dc:date>2021-08-17</dc:date>
<dc:identifier>doi:10.1101/2021.08.17.456617</dc:identifier>
<dc:title><![CDATA[Distinct neural circuits establish the same chemosensory behavior in C. elegans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.21.457209v1?rss=1">
<title>
<![CDATA[
Resting Parasympathetic Nervous System Activity is Associated with Greater Antiviral Gene Expression 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.21.457209v1?rss=1</link>
<description><![CDATA[
Parasympathetic nervous system activity can downregulate inflammation, but it remains unclear how parasympathetic nervous system activity relates to antiviral activity. The present study examined associations between parasympathetic nervous system activity and cellular antiviral gene regulation in 90 adolescents (Mage = 16.3, SD = 0.7; 51.1% female) who provided blood samples and measures of cardiac respiratory sinus arrhythmia (RSA), twice, five weeks apart. Using a multilevel analytic framework, we found that higher RSA (an indicator of higher parasympathetic nervous system activity)--both at rest and during paced breathing--was associated with higher expression of Type I interferon (IFN) response genes in circulating leukocytes, even after adjusting for demographic and biological covariates. RSA was not associated with a parallel measure of inflammatory gene expression. These results identify a previously unrecognized immunoregulatory aspect of autonomic nervous system function and highlight a potential biological pathway by which parasympathetic nervous system activity may relate to health.
]]></description>
<dc:creator>Rahal, D.</dc:creator>
<dc:creator>Tashjian, S. M.</dc:creator>
<dc:creator>Karan, M.</dc:creator>
<dc:creator>Eisenberger, N.</dc:creator>
<dc:creator>Galvan, A.</dc:creator>
<dc:creator>Fuligni, A. J.</dc:creator>
<dc:creator>Cole, S. W.</dc:creator>
<dc:date>2021-08-23</dc:date>
<dc:identifier>doi:10.1101/2021.08.21.457209</dc:identifier>
<dc:title><![CDATA[Resting Parasympathetic Nervous System Activity is Associated with Greater Antiviral Gene Expression]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.22.457288v1?rss=1">
<title>
<![CDATA[
Integrative Genome Modeling Platform reveals essentialityof rare contact events in 3D genome organizations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.22.457288v1?rss=1</link>
<description><![CDATA[
A multitude of sequencing-based and microscopy technologies provide the means to unravel the relationship between the three-dimensional (3D) organization of genomes and key regulatory processes of genome function. However, it remains a major challenge to systematically integrate all available data sources to characterize the nuclear organization of genomes across different spatial scales. Here, we develop a multi-modal data integration approach to produce genome structures that are highly predictive for nuclear locations of genes and nuclear bodies, local chromatin compaction, and spatial segregation of functionally related chromatin.

By performing a quantitative assessment of the predictive power of genome structures generated from different data combinations, we demonstrate that multimodal data integration can compensate for systematic errors and missing values in some of the data and thus, greatly increases accuracy and coverage of genome structure models. We also show that alternative combinations of different orthogonal data sources can converge to models with similar predictive power. Moreover, our study reveals the key contributions of low-frequency inter-chromosomal contacts (e.g., "rare" contact events) to accurately predicting the global nuclear architecture, including the positioning of genes and chromosomes. Overall, our results highlight the benefits of multi-modal data integration for genome structure analysis, available through the Integrative Genome structure Modeling (IGM) software package that we introduce here.
]]></description>
<dc:creator>Boninsegna, L.</dc:creator>
<dc:creator>Yildirim, A.</dc:creator>
<dc:creator>Polles, G.</dc:creator>
<dc:creator>Quinodoz, S. A.</dc:creator>
<dc:creator>Finn, E. H.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:creator>Zhou, X. J.</dc:creator>
<dc:creator>Alber, F.</dc:creator>
<dc:date>2021-08-23</dc:date>
<dc:identifier>doi:10.1101/2021.08.22.457288</dc:identifier>
<dc:title><![CDATA[Integrative Genome Modeling Platform reveals essentialityof rare contact events in 3D genome organizations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.25.457696v1?rss=1">
<title>
<![CDATA[
The Specious Art of Single-Cell Genomics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.25.457696v1?rss=1</link>
<description><![CDATA[
Dimensionality reduction is standard practice for filtering noise and identifying relevant features in large-scale data analyses. In biology, single-cell genomics studies typically begin with reduction to two or three dimensions to produce  all-in-one visuals of the data that are amenable to the human eye, and these are subsequently used for qualitative and quantitative exploratory analysis. However, there is little theoretical support for this practice, and we show that extreme dimension reduction, from hundreds or thousands of dimensions to two, inevitably induces significant distortion of high-dimensional datasets. We therefore examine the practical implications of low-dimensional embedding of single-cell data, and find that extensive distortions and inconsistent practices make such embeddings counter-productive for exploratory, biological analyses. In lieu of this, we discuss alternative approaches for conducting targeted embedding and feature exploration, to enable hypothesis-driven biological discovery.
]]></description>
<dc:creator>Chari, T.</dc:creator>
<dc:creator>Banerjee, J.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2021-08-26</dc:date>
<dc:identifier>doi:10.1101/2021.08.25.457696</dc:identifier>
<dc:title><![CDATA[The Specious Art of Single-Cell Genomics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.26.457822v1?rss=1">
<title>
<![CDATA[
The entomopathogenic nematode Steinernema hermaphroditum  is a self-fertilizing hermaphrodite and a genetically tractable system for the study of parasitic and mutualistic symbiosis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.26.457822v1?rss=1</link>
<description><![CDATA[
Entomopathogenic nematodes, including Heterorhabditis and Steinernema, are parasitic to insects and contain mutualistically symbiotic bacteria in their intestines (Photorhabdus and Xenorhabdus, respectively) and therefore offer opportunities to study both mutualistic and parasitic symbiosis. The establishment of genetic tools in entomopathogenic nematodes has been impeded by limited genetic tractability, inconsistent growth in vitro, variable cryopreservation, and low mating efficiency. We obtained the recently described Steinernema hermaphroditum strain CS34 and optimized its in vitro growth, with a rapid generation time on a lawn of its native symbiotic bacteria Xenorhabdus griffiniae. We developed a simple and efficient cryopreservation method. Previously, S. hermaphroditum isolated from insect hosts was described as first-generation hermaphroditic and second-generation gonochoristic. We discovered that CS34, when grown in vitro, produced consecutive generations of autonomously reproducing hermaphrodites accompanied by rare males. We performed mutagenesis screens in S. hermaphroditum that produced mutant lines with visible and heritable phenotypes. Genetic analysis of the mutants demonstrated that this species reproduces by self-fertilization rather than parthenogenesis and that its sex is determined chromosomally. Genetic mapping has thus far identified markers on the X chromosome and three of four autosomes. We report that S. hermaphroditum CS34 is the first consistently hermaphroditic entomopathogenic nematode and is suitable for genetic model development to study naturally occurring mutualistic symbiosis and insect parasitism.
]]></description>
<dc:creator>Cao, M.</dc:creator>
<dc:creator>Schwartz, H. T.</dc:creator>
<dc:creator>Tan, C.-H.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2021-08-27</dc:date>
<dc:identifier>doi:10.1101/2021.08.26.457822</dc:identifier>
<dc:title><![CDATA[The entomopathogenic nematode Steinernema hermaphroditum  is a self-fertilizing hermaphrodite and a genetically tractable system for the study of parasitic and mutualistic symbiosis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.27.457205v1?rss=1">
<title>
<![CDATA[
The STAT5-IRF4-BATF pathway drives heightened epigenetic remodeling in naïve CD4+ T cell responses of older adults 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.27.457205v1?rss=1</link>
<description><![CDATA[
T cell aging is a complex process combining the emergence of cellular defects with activation of adaptive mechanisms. Generation of T cell memory is impaired, while a low-inflammatory state is induced, in part due to effector T cells. To determine whether age-associated changes in T cell fate decisions occur early after T cell activation, we profiled the longitudinal transcriptional and epigenetic landscape induced by TCR stimulation comparing naive CD4+ T cells from young and older adults. In spite of attenuated TCR signaling, activation-induced remodeling of the epigenome increased with age, culminating in heightened BATF and BLIMP1 activity. Single cell studies, integrating ATAC-seq and RNA-seq data, identified increases in dysfunctional and in effector T cells and a decrease in BACH2-expressing memory cell precursors. STAT5 activation, in part due to a decline in HELIOS and aberrant IL-2 receptor expression, accounted for the induction of transcription factor networks favoring effector cell differentiation.
]]></description>
<dc:creator>Zhang, H.</dc:creator>
<dc:creator>Jadhav, R. R.</dc:creator>
<dc:creator>Cao, W.</dc:creator>
<dc:creator>Goronzy, I. N.</dc:creator>
<dc:creator>Jin, J.</dc:creator>
<dc:creator>Greenleaf, W. J.</dc:creator>
<dc:creator>Weyand, C. M.</dc:creator>
<dc:creator>Goronzy, J.</dc:creator>
<dc:date>2021-08-28</dc:date>
<dc:identifier>doi:10.1101/2021.08.27.457205</dc:identifier>
<dc:title><![CDATA[The STAT5-IRF4-BATF pathway drives heightened epigenetic remodeling in naïve CD4+ T cell responses of older adults]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.31.458470v1?rss=1">
<title>
<![CDATA[
Hopanoids confer robustness to physicochemical variability in the niche of the plant symbiont Bradyrhizobium diazoefficiens 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.31.458470v1?rss=1</link>
<description><![CDATA[
Climate change poses a threat to soil health and agriculture, but the potential effects of climate change on soil bacteria that can help maintain soil health are understudied. Rhizobia are a group of bacteria that increase soil nitrogen content through a symbiosis with legume plants. The soil and symbiosis are potentially stressful environments, and the soil will likely become even more stressful as the climate changes. Many rhizobia within the bradyrhizobia clade, like Bradyrhizobium diazoefficiens, possess the genetic capacity to synthesize hopanoids, steroid-like lipids similar in structure and function to cholesterol. Hopanoids are known to protect against stresses relevant to the niche of B. diazoefficiens. Paradoxically, mutants unable to synthesize the extended class of hopanoids participate in similarly successful symbioses compared to the wild type, despite being delayed in root nodule initiation. Here, we show that in B. diazoefficiens, the in vitro growth defects of extended hopanoid deficient mutants can be at least partially compensated for by the physicochemical environment, specifically by optimal osmotic and divalent cation concentrations. Through biophysical measurements, we show that extended hopanoids confer robustness to environmental variability. These results help explain the discrepancy between previous in vitro and in planta results and indicate that hopanoids may provide a greater fitness advantage to rhizobia in the variable soil environment than the more controlled environment within root nodules. To improve the legume-rhizobia symbiosis through either bioengineering or strain selection, it will be important to consider the full lifecycle of rhizobia, from the soil to the symbiosis.

ImportanceRhizobia, such as B. diazoefficiens, play an important role in the nitrogen cycle by making nitrogen gas bioavailable through symbiosis with legume plants. As climate change threatens soil health, this symbiosis has reentered the spotlight as a more sustainable source of soil nitrogen than the energy-intensive Haber-Bosch process. Efforts to use rhizobia as biofertilizers have been effective; however, long term integration of rhizobia into the soil community has been less successful. This work represents a small step towards improving the legume-rhizobia symbiosis by identifying a cellular component--hopanoid lipids--that confers robustness to environmental stresses rhizobia are likely to encounter in soil microenvironments as sporadic desiccation and flooding events become more common.
]]></description>
<dc:creator>Tookmanian, E. M.</dc:creator>
<dc:creator>Junghans, L.</dc:creator>
<dc:creator>Kulkarni, G.</dc:creator>
<dc:creator>Ledermann, R.</dc:creator>
<dc:creator>Saenz, J. P.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2021-09-01</dc:date>
<dc:identifier>doi:10.1101/2021.08.31.458470</dc:identifier>
<dc:title><![CDATA[Hopanoids confer robustness to physicochemical variability in the niche of the plant symbiont Bradyrhizobium diazoefficiens]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.03.458819v1?rss=1">
<title>
<![CDATA[
Metabolic modeling of the International Space Station microbiome reveals key microbial interactions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.03.458819v1?rss=1</link>
<description><![CDATA[
BackgroundRecent studies have provided insights into the persistence and succession of microbes aboard the International Space Station (ISS), notably the dominance of Klebsiella pneumoniae. However, the interactions between the various microbes aboard the ISS, and how it shapes the microbiome remain to be clearly understood. In this study, we apply a computational approach to predict possible metabolic interactions in the ISS microbiome and shed further light on its organization.

ResultsThrough a combination of a systems-based graph-theoretical approach, and a constraint-based community metabolic modelling approach, we demonstrated several key interactions in the ISS microbiome. These complementary approaches provided insights into the metabolic interactions and dependencies present amongst various microbes in a community, highlighting key interactions and keystone species. Our results showed that the presence of K. pneumoniae is beneficial to many other microorganisms it coexists with, notably those from the Pantoea genus. Species belonging to the Enterobacteriaceae family were often found to be the most beneficial for the survival of other microorganisms in the ISS microbiome. However, K. pneumoniae was found to exhibit parasitic and amensalistic interactions with Aspergillus and Penicillium species, respectively. To prove this metabolic prediction, K. pneumoniae and Aspergillus fumigatus were co-cultured under normal and simulated microgravity, where K. pneumoniae cells showed parasitic characteristics to the fungus. The electron micrography revealed that the presence of K. pneumoniae compromised the morphology of fungal conidia and its biofilm biofilm-forming structures.

ConclusionsOur study underscores the importance of K. pneumoniae in the ISS, and its potential contribution to the survival (mutualism) and eradication (parasitism) of other microbes, including potential pathogens. This integrated modelling approach, combined with experiments, demonstrates immense potential for understanding the organization of other such microbiomes, unravelling key organisms and their interdependencies.
]]></description>
<dc:creator>Kumar, R. K.</dc:creator>
<dc:creator>Singh, N. K.</dc:creator>
<dc:creator>Balakrishnan, S.</dc:creator>
<dc:creator>Parker, C. W.</dc:creator>
<dc:creator>Raman, K.</dc:creator>
<dc:creator>Venkateswaran, K.</dc:creator>
<dc:date>2021-09-04</dc:date>
<dc:identifier>doi:10.1101/2021.09.03.458819</dc:identifier>
<dc:title><![CDATA[Metabolic modeling of the International Space Station microbiome reveals key microbial interactions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.03.458834v1?rss=1">
<title>
<![CDATA[
Chronic exposure to odors at naturally occurring concentrations triggers limited plasticity in early stages of Drosophila olfactory processing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.03.458834v1?rss=1</link>
<description><![CDATA[
In insects and mammals, olfactory experience in early life alters olfactory behavior and function in later life. In the vinegar fly Drosophila, flies chronically exposed to a high concentration of a monomolecular odor exhibit reduced behavioral aversion to the familiar odor when it is re- encountered. This change in olfactory behavior has been attributed to selective decreases in the sensitivity of second-order olfactory projection neurons (PNs) in the antennal lobe that respond to the overrepresented odor. However, since odorant compounds do not occur at similarly high concentrations in natural sources, the role of odor experience-dependent plasticity in natural environments is unclear. Here, we investigated olfactory plasticity in the antennal lobe of flies chronically exposed to odors at concentrations that are typically encountered in natural odor sources. These stimuli were chosen to each strongly and selectively excite a single PN type to saturating firing rates, facilitating a rigorous assessment of the selectivity of olfactory plasticity for PNs directly excited by overrepresented stimuli. Unexpectedly, we found that chronic exposure to three such odors did not result in decreased PN sensitivity, but rather mildly increased responses to weak stimuli in most PN types. Odor-evoked PN activity in response to stronger stimuli was mostly unaffected by odor experience. When present, plasticity was observed broadly in multiple PN types and thus was not selective for PNs receiving direct input from the chronically active ORNs. We further investigated the DL5 olfactory coding channel and found that chronic odor-mediated excitation of its input ORNs did not affect PN intrinsic properties, local inhibitory innervation, ORN responses, or ORN-PN synaptic strength; however, broad-acting lateral excitation evoked by some odors was increased. These results show that PN odor coding is only mildly affected by strong persistent activation of a single olfactory input, highlighting the stability of early stages of insect olfactory processing to significant perturbations in the sensory environment.
]]></description>
<dc:creator>Hong, E. J.</dc:creator>
<dc:creator>Gugel, Z. V.</dc:creator>
<dc:creator>Maurais, E.</dc:creator>
<dc:date>2021-09-03</dc:date>
<dc:identifier>doi:10.1101/2021.09.03.458834</dc:identifier>
<dc:title><![CDATA[Chronic exposure to odors at naturally occurring concentrations triggers limited plasticity in early stages of Drosophila olfactory processing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.03.458937v1?rss=1">
<title>
<![CDATA[
A novel widespread bacterial structure related to the flagellar type III secretion system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.03.458937v1?rss=1</link>
<description><![CDATA[
The flagellar type III secretion system (fT3SS) is a suite of membrane-embedded and cytoplasmic proteins responsible for building the bacterial flagellar motility machinery. Homologous proteins form the injectisome machinery bacteria use to deliver effector proteins into eukaryotic cells, and other family members have recently been reported to be involved in the formation of membrane nanotubes. Here we describe a novel, ubiquitous and evolutionarily widespread hat-shaped structure embedded in the inner membrane of bacteria, of yet-unidentified function, that is related to the fT3SS, adding to the already rich repertoire of this family of nanomachines.
]]></description>
<dc:creator>Kaplan, M.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>Wood, c. R.</dc:creator>
<dc:creator>Chreifi, G.</dc:creator>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Dobro, M.</dc:creator>
<dc:creator>Yao, Q.</dc:creator>
<dc:creator>McDowall, A.</dc:creator>
<dc:creator>Briegel, A.</dc:creator>
<dc:creator>Beeby, M.</dc:creator>
<dc:creator>Chang, Y.-W.</dc:creator>
<dc:creator>Shaffer, C.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2021-09-04</dc:date>
<dc:identifier>doi:10.1101/2021.09.03.458937</dc:identifier>
<dc:title><![CDATA[A novel widespread bacterial structure related to the flagellar type III secretion system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.03.458944v1?rss=1">
<title>
<![CDATA[
Single-cell perturbation dissects transcription factor control of progression speed and trajectory choice in early T-cell development 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.03.458944v1?rss=1</link>
<description><![CDATA[
In early T-cell development, single cells dynamically shift expression of multiple transcription factors (TFs) during transition from multipotentiality to T-lineage commitment, but the functional roles of many TFs have been obscure. Here, synchronized in vitro differentiation systems, scRNA-seq with batch indexing, and controlled gene-disruption strategies have unraveled single-cell impacts of perturbing individual TFs at two stages in early T-cell development. Single-cell CRISPR perturbation revealed that early-acting TFs Bcl11a, Erg, Spi1 (PU.1), Gata3, and Tcf7 (TCF1) each play individualized roles promoting or retarding T-lineage progression and suppressing alternative trajectories, collectively determining population dynamics and path topologies. Later, during T-lineage commitment, cells prevented from expressing TF Bcl11b  realized this abnormality not with a developmental block, but by shifting into a divergent path via bZIP and Sox TF activation as well as E protein antagonism, finally exiting the T-lineage trajectory. These TFs thus exert a network of impacts to control progression kinetics, trajectories, and differentiation outcomes of early pro-T cells.
]]></description>
<dc:creator>Zhou, W.</dc:creator>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>Romero-Wolf, M.</dc:creator>
<dc:creator>Jo, S.</dc:creator>
<dc:creator>Rothenberg, E. V.</dc:creator>
<dc:date>2021-09-06</dc:date>
<dc:identifier>doi:10.1101/2021.09.03.458944</dc:identifier>
<dc:title><![CDATA[Single-cell perturbation dissects transcription factor control of progression speed and trajectory choice in early T-cell development]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.04.458989v1?rss=1">
<title>
<![CDATA[
Entry to and exit from diapause arrest in Caenorhabditis elegans are both regulated by a steroid hormone pathway 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.04.458989v1?rss=1</link>
<description><![CDATA[
Diapause arrest in animals such as Caenorhabditis elegans is tightly regulated so that animals make appropriate developmental decisions amidst environmental challenges. Fully understanding diapause requires mechanistic insight of both entry and exit from the arrested state. While a steroid hormone pathway regulates the entry decision into Caenorhabditis elegans dauer diapause, its role in the exit decision is less clear. A complication to understanding steroid hormonal regulation of dauer has been the peculiar fact that steroid hormone mutants such as daf-9 form partial dauers under normal growth conditions. Here, we corroborate previous findings that daf-9 mutants remain capable of forming full dauers under unfavorable growth conditions, and we establish that the daf-9 partial dauer state is likely a partially exited dauer that has initiated but cannot complete the dauer exit decision. We show that the steroid hormone pathway is both necessary for and promotes complete dauer exit, and that the spatiotemporal dynamics of steroid hormone regulation during dauer exit resembles that of dauer entry. Overall, dauer entry and dauer exit are distinct developmental decisions that are both controlled by steroid hormone signaling.

Summary StatementIn animals such as Caenorhabditis elegans, a steroid hormone pathway controls both the entry and exit decisions into and out of the developmentally arrested dauer state in response to environmental signaling.
]]></description>
<dc:creator>Zhang, M. G.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2021-09-06</dc:date>
<dc:identifier>doi:10.1101/2021.09.04.458989</dc:identifier>
<dc:title><![CDATA[Entry to and exit from diapause arrest in Caenorhabditis elegans are both regulated by a steroid hormone pathway]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.06.459173v1?rss=1">
<title>
<![CDATA[
Interpretable and tractable models of transcriptional noise for the rational design of single-molecule quantification experiments 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.06.459173v1?rss=1</link>
<description><![CDATA[
The question of how cell-to-cell differences in transcription rate affect RNA count distributions is fundamental for understanding biological processes underlying transcription. We argue that answering this question requires quantitative models that are both interpretable (describing concrete biophysical phenomena) and tractable (amenable to mathematical analysis). This enables the identification of experiments which best discriminate between competing hypotheses. As a proof of principle, we introduce a simple but flexible class of models involving a stochastic transcription rate coupled to a discrete stochastic RNA transcription and splicing process, and compare and contrast two biologically plausible hypotheses about transcription rate variation. One assumes variation is due to DNA experiencing mechanical strain, while the other assumes it is due to regulator number fluctuations. Although biophysically distinct, these models are mathematically similar, and we show they are hard to distinguish without comparing whole predicted probability distributions. Our work illustrates the importance of theory-guided data collection, and introduces a general framework for constructing and solving mathematically nontrivial continuous-discrete stochastic models.

Significance StatementThe interpretation of transcriptomic observations requires detailed models of biophysical noise that can be compared and fit to experimental data. Models of intrinsic noise, describing stochasticity in molecular reactions, and extrinsic noise, describing cell-to-cell variation, are particularly common. However, integrating and solving them is challenging, and previous results are largely limited to summary statistics. We examine two mechanistically grounded stochastic models of transcriptional variation and demonstrate that (1) well-known regimes naturally emerge in limiting cases, and (2) the choice of noise model significantly affects the RNA distributions, but not the lower moments, offering a route to model identification and inference. This approach provides a simple and biophysically interpretable means to construct and unify models of transcriptional variation.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Vastola, J. J.</dc:creator>
<dc:creator>Fang, M.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2021-09-06</dc:date>
<dc:identifier>doi:10.1101/2021.09.06.459173</dc:identifier>
<dc:title><![CDATA[Interpretable and tractable models of transcriptional noise for the rational design of single-molecule quantification experiments]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.08.459490v1?rss=1">
<title>
<![CDATA[
Spatio-temporal coordination at the maternal-fetal interface promotes trophoblast invasion and vascular remodeling in the first half of human pregnancy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.08.459490v1?rss=1</link>
<description><![CDATA[
Beginning in the first trimester, fetally derived extravillous trophoblasts (EVTs) invade the uterus and remodel its spiral arteries, transforming them into large, dilated blood vessels left with a thin, discontinuous smooth muscle layer and partially lined with EVTs. Several mechanisms have been proposed to explain how EVTs coordinate with the maternal decidua to promote a tissue microenvironment conducive to spiral artery remodeling (SAR). However, it remains a matter of debate which immune and stromal cell types participate in these interactions and how this process evolves with respect to gestational age. Here, we used a multiomic approach that combined the strengths of spatial proteomics and transcriptomics to construct the first spatiotemporal atlas of the human maternal-fetal interface in the first half of pregnancy. We used multiplexed ion beam imaging by time of flight (MIBI-TOF) and a 37-plex antibody panel to analyze [~]500,000 cells and 588 spiral arteries within intact decidua from 66 patients between 6-20 weeks of gestation, integrating this with coregistered transcriptomic profiles. Gestational age substantially influenced the frequency of many maternal immune and stromal cells, with tolerogenic subsets expressing CD206, CD163, TIM-3, Galectin-9, and IDO-1 increasingly enriched and colocalized at later time points. In contrast, SAR progression preferentially correlated with EVT invasion and was transcriptionally defined by 78 gene ontology pathways exhibiting unique monotonic and biphasic trends. Lastly, we developed an integrated model of SAR supporting an intravasation mechanism where invasion is accompanied by upregulation of pro-angiogenic, immunoregulatory EVT programs that promote interactions with vascular endothelium while avoiding activation of immune cells in circulating maternal blood. Taken together, these results support a coordinated model of decidualization in which increasing gestational age drives a transition in maternal decidua towards a tolerogenic niche conducive to locally regulated, EVT-dependent SAR.
]]></description>
<dc:creator>Greenbaum, S.</dc:creator>
<dc:creator>Averbukh, I.</dc:creator>
<dc:creator>Soon, E.</dc:creator>
<dc:creator>Rizzuto, G.</dc:creator>
<dc:creator>Baranski, A.</dc:creator>
<dc:creator>Greenwald, N.</dc:creator>
<dc:creator>Bosse, M.</dc:creator>
<dc:creator>Jaswa, E. G.</dc:creator>
<dc:creator>Khair, Z.</dc:creator>
<dc:creator>Kwok, S.</dc:creator>
<dc:creator>Warshawsky, S.</dc:creator>
<dc:creator>Miller, G.</dc:creator>
<dc:creator>Schwartz, M.</dc:creator>
<dc:creator>Graf, W.</dc:creator>
<dc:creator>Van Valen, D.</dc:creator>
<dc:creator>Keren, L.</dc:creator>
<dc:creator>Hollmann, T.</dc:creator>
<dc:creator>van de Rijn, M.</dc:creator>
<dc:creator>Angelo, M.</dc:creator>
<dc:date>2021-09-10</dc:date>
<dc:identifier>doi:10.1101/2021.09.08.459490</dc:identifier>
<dc:title><![CDATA[Spatio-temporal coordination at the maternal-fetal interface promotes trophoblast invasion and vascular remodeling in the first half of human pregnancy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.12.459953v1?rss=1">
<title>
<![CDATA[
Layered Feedback Control Overcomes Performance Trade-off in Synthetic Biomolecular Networks 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.12.459953v1?rss=1</link>
<description><![CDATA[
Layered feedback is an optimization strategy in feedback control designs widely used in electrical and mechanical engineering. Layered control theory suggests that the performance of controllers is bound by the universal robustness-efficiency tradeoff limit, which could be overcome by layering two or more feedbacks together. In natural biological networks, genes are often regulated with redundancy and layering to adapt to environmental perturbations. Control theory hypothesizes that this layering architecture is also adopted by nature to overcome this performance trade-off. In this work, we validated this property of layered control with a synthetic network in living E. coli cells. We performed system analysis on a node-based design to confirm the tradeoff properties before proceeding to simulations with an effective mechanistic model, which guided us to the best performing design to engineer in cells. Finally, we interrogated its system dynamics experimentally with eight sets of perturbations on chemical signals, nutrient abundance, and growth temperature. For all cases, we consistently observed that the layered control overcomes the robustness-efficiency trade-off limit. This work experimentally confirmed that layered control could be adopted in synthetic biomolecular networks as a performance optimization strategy. It also provided insights in understanding genetic feedback control architectures in nature.



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]]></description>
<dc:creator>Hu, C. Y.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2021-09-13</dc:date>
<dc:identifier>doi:10.1101/2021.09.12.459953</dc:identifier>
<dc:title><![CDATA[Layered Feedback Control Overcomes Performance Trade-off in Synthetic Biomolecular Networks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.14.460356v1?rss=1">
<title>
<![CDATA[
Rapid Identification of Neutralizing Antibodies against SARS-CoV-2 Variants by mRNA Display 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.14.460356v1?rss=1</link>
<description><![CDATA[
The increasing prevalence of SARS-CoV-2 variants with the ability to escape existing humoral protection conferred by previous infection and/or immunization necessitates the discovery of broadly-reactive neutralizing antibodies (nAbs). Utilizing mRNA display, we identified a set of antibodies against SARS-CoV-2 spike (S) proteins and characterized the structures of nAbs that recognized epitopes in the S1 subunit of the S glycoprotein. These structural studies revealed distinct binding modes for several antibodies, including targeting of rare cryptic epitopes in the receptor-binding domain (RBD) of S that interacts with angiotensin- converting enzyme 2 (ACE2) to initiate infection, as well as the S1 subdomain 1. A potent ACE2-blocking nAb was further engineered to sustain binding to S RBD with the E484K and L452R substitutions found in multiple SARS-CoV-2 variants. We demonstrate that mRNA display is a promising approach for the rapid identification of nAbs that can be used in combination to combat emerging SARS-CoV-2 variants.
]]></description>
<dc:creator>Tanaka, S.</dc:creator>
<dc:creator>Olson, C. A.</dc:creator>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Higashide, W.</dc:creator>
<dc:creator>Gonzales, M.</dc:creator>
<dc:creator>Taft, J.</dc:creator>
<dc:creator>Richardson, A.</dc:creator>
<dc:creator>Martin-Fernandez, M.</dc:creator>
<dc:creator>Bogunovic, D.</dc:creator>
<dc:creator>Gnanapragasam, P. N. P.</dc:creator>
<dc:creator>Bjorkman, P.</dc:creator>
<dc:creator>Spilman, P. R.</dc:creator>
<dc:creator>Niazi, K.</dc:creator>
<dc:creator>Rabizadeh, S.</dc:creator>
<dc:creator>Soon-Shiong, P.</dc:creator>
<dc:date>2021-09-15</dc:date>
<dc:identifier>doi:10.1101/2021.09.14.460356</dc:identifier>
<dc:title><![CDATA[Rapid Identification of Neutralizing Antibodies against SARS-CoV-2 Variants by mRNA Display]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.18.460850v1?rss=1">
<title>
<![CDATA[
Lysosome-related organelles contain an expansion compartment that mediates delivery of zinc transporters to promote homeostasis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.18.460850v1?rss=1</link>
<description><![CDATA[
Lysosome-related organelles play evolutionarily conserved roles in zinc storage, but mechanisms that control zinc flow in and out are not well understood. In C. elegans intestinal cells, the CDF-2 transporter stores zinc in these organelles during excess. Here we identify ZIPT-2.3 as the transporter that releases zinc during deficiency. The expression levels of CDF-2 and ZIPT-2.3 are reciprocally regulated in zinc excess and deficiency, establishing a fundamental mechanism of homeostasis. Super-resolution microscopy demonstrated these organelles are composed of a spherical acidified compartment and a hemispherical expansion compartment. The expansion compartment inflates during zinc excess and deficiency by vesicle fusion delivering zinc transporters. These results identify an unexpected structural feature of lysosome-related organelles that facilitates rapid transitions in the composition of zinc transporters to mediate homeostasis.
]]></description>
<dc:creator>Mendoza, A. D.</dc:creator>
<dc:creator>Dietrich, N.</dc:creator>
<dc:creator>Tan, C.-H.</dc:creator>
<dc:creator>Herrera, D. E.</dc:creator>
<dc:creator>Kasiah, J.</dc:creator>
<dc:creator>Payne, Z.</dc:creator>
<dc:creator>Schneider, D. L.</dc:creator>
<dc:creator>Kornfeld, K.</dc:creator>
<dc:date>2021-09-19</dc:date>
<dc:identifier>doi:10.1101/2021.09.18.460850</dc:identifier>
<dc:title><![CDATA[Lysosome-related organelles contain an expansion compartment that mediates delivery of zinc transporters to promote homeostasis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.23.461487v1?rss=1">
<title>
<![CDATA[
Ratiometric RNA labeling allows dynamic multiplexed analysis of gene circuits in single cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.23.461487v1?rss=1</link>
<description><![CDATA[
Biological processes are highly dynamic and are regulated by genes that connect with one and another, forming regulatory circuits and networks. Understanding how gene regulatory circuits operate dynamically requires monitoring the expression of multiple genes in the same cell. However, it is limited by the relatively few distinguishable fluorescent proteins. Here, we developed a multiplexed real-time transcriptional imaging method based on two RNA stem-loop binding proteins, and employed it to analyze the temporal dynamics of synthetic gene circuits. By incorporating different ratios of MS2 and PP7 stem-loops, we were able to monitor the real-time nascent transcriptional activities of up to five genes in the same cell using only two fluorescent proteins. Applying this multiplexing capability to synthetic linear or branched gene regulatory cascades revealed that propagation of transcriptional dynamics is enhanced by non-stationary dynamics and is dictated by the slowest regulatory branch in the presence of combinatorial regulation. Mathematical modeling provided further insight into temporal multi-gene interactions and helped to understand potential challenges in regulatory inference using snapshot single-cell data. Ratiometric multiplexing should scale exponentially with additional labelling channels, providing a way to track the dynamics of larger circuits.
]]></description>
<dc:creator>Xu, S.</dc:creator>
<dc:creator>Li, K.</dc:creator>
<dc:creator>Ma, L.</dc:creator>
<dc:creator>Zhang, J.</dc:creator>
<dc:creator>Yoon, S.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:creator>Lin, Y.</dc:creator>
<dc:date>2021-09-23</dc:date>
<dc:identifier>doi:10.1101/2021.09.23.461487</dc:identifier>
<dc:title><![CDATA[Ratiometric RNA labeling allows dynamic multiplexed analysis of gene circuits in single cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.23.461548v1?rss=1">
<title>
<![CDATA[
A rise-to-threshold signal for a relative value deliberation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.23.461548v1?rss=1</link>
<description><![CDATA[
Whereas progress has been made in identifying neural signals related to rapid, cued decisions1-4, less is known about how brains guide and terminate more ethologically relevant deliberations, where an animals own behavior governs the options experienced over minutes5-8. Drosophila search for many seconds to minutes for egg-laying sites with high relative value9, 10 and neurons, called oviDNs, exist whose activity fulfills necessity and sufficiency criteria for initiating the egg-deposition motor program11. Here we show that oviDNs express a calcium signal that rises over seconds to minutes as a fly deliberates whether to lay an egg. The calcium signal dips when an egg is internally prepared (ovulated), rises at a rate related to the relative value of the current substrate being experienced, and reaches a consistent peak just prior to the abdomen bend for egg deposition. We provide perturbational evidence that the egg-deposition motor program is initiated once this signal hits a threshold and that sub-threshold variation in the signal regulates the time spent deliberating and, ultimately, the option chosen. These results argue that a rise-to-threshold signal guides Drosophila to lay eggs on substrate options with high relative value, with each egg-laying event representing a self-paced decision similar to real-world decisions made by humans and other mammals.
]]></description>
<dc:creator>Vijayan, V.</dc:creator>
<dc:creator>Wang, F.</dc:creator>
<dc:creator>Wang, K.</dc:creator>
<dc:creator>Chakravorty, A.</dc:creator>
<dc:creator>Adachi, A.</dc:creator>
<dc:creator>Akhlaghpour, H.</dc:creator>
<dc:creator>Dickson, B. J.</dc:creator>
<dc:creator>Maimon, G.</dc:creator>
<dc:date>2021-09-24</dc:date>
<dc:identifier>doi:10.1101/2021.09.23.461548</dc:identifier>
<dc:title><![CDATA[A rise-to-threshold signal for a relative value deliberation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.23.461613v1?rss=1">
<title>
<![CDATA[
Mechanics Of Ultrasonic Neuromodulation In A Mouse Subject 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.23.461613v1?rss=1</link>
<description><![CDATA[
Ultrasound neuromodulation (UNM), where a region in the brain is targeted by focused ultrasound (FUS), which, in turn, causes excitation or inhibition of neural activity, has recently received considerable attention as a promising tool for neuroscience. Despite its great potential, several aspects of UNM are still unknown. An important question pertains to the off-target sensory effects of UNM and their dependence on stimulation frequency. To understand these effects, we have developed a finite-element model of a mouse, including elasticity and viscoelasticity, and used it to interrogate the response of mouse models to focused ultrasound (FUS). We find that, while some degree of focusing and magnification of the signal is achieved within the brain, the induced pressure-wave pattern is complex and delocalized. In addition, we find that the brain is largely insulated, or  cloaked, from shear waves by the cranium and that the shear waves are largely carried away from the skull by the vertebral column, which acts as a waveguide. We find that, as expected, this waveguide mechanism is strongly frequency dependent, which may contribute to the frequency dependence of UNM effects. Our calculations further suggest that off-target skin locations experience displacements and stresses at levels that, while greatly attenuated from the source, could nevertheless induce sensory responses in the subject.
]]></description>
<dc:creator>Salahshoor, H.</dc:creator>
<dc:creator>Guo, H.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Ortiz, M.</dc:creator>
<dc:date>2021-09-24</dc:date>
<dc:identifier>doi:10.1101/2021.09.23.461613</dc:identifier>
<dc:title><![CDATA[Mechanics Of Ultrasonic Neuromodulation In A Mouse Subject]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.24.461604v1?rss=1">
<title>
<![CDATA[
Gene identification and genome annotation in Caenorhabditis briggsae by high throughput 5' RNA end determination 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.24.461604v1?rss=1</link>
<description><![CDATA[
The nematode Caenorhabditis briggsae is routinely used in comparative and evolutionary studies involving its well-known cousin C. elegans. The C. briggsae genome sequence has accelerated research by facilitating the generation of new resources, tools, and functional studies of genes. While substantial progress has been made in predicting genes and start sites, experimental evidence is still lacking in many cases. Here, we report an improved annotation of the C. briggsae genome using the Trans-spliced Exon Coupled RNA End Determination (TEC-RED) technique. In addition to identifying the 5 ends of expressed genes, we have discovered operons and paralogs. In summary, our analysis yielded 10,243 unique 5 end sequence tags with matches in the C. briggsae genome. Of these, 6,395 were found to represent 4,252 unique genes along with 362 paralogs and 52 previously unknown exons. These genes included 14 that are exclusively trans-spliced in C. briggsae when compared with C. elegans orthologs. A major contribution of this study is the identification of 493 operons, of which two-thirds are fully supported by tags. In addition, two SL1-type operons were discovered. Interestingly, comparisons with C. elegans showed that only 40% of operons are conserved. Of the remaining operons, 73 are novel, including 12 that entirely lack orthologs in C. elegans. Further analysis revealed that four of the 12 novel operons are conserved in C. nigoni. Altogether, the work described here has significantly advanced our understanding of the C. briggsae system and serves as a rich resource to aid biological studies involving this species.
]]></description>
<dc:creator>Jhaveri, N.</dc:creator>
<dc:creator>van den Berg, W.</dc:creator>
<dc:creator>Hwang, B. J.</dc:creator>
<dc:creator>Muller, H.-M.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Gupta, B. P.</dc:creator>
<dc:date>2021-09-24</dc:date>
<dc:identifier>doi:10.1101/2021.09.24.461604</dc:identifier>
<dc:title><![CDATA[Gene identification and genome annotation in Caenorhabditis briggsae by high throughput 5' RNA end determination]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.25.461819v1?rss=1">
<title>
<![CDATA[
Comparative genomics reveals electron transfer and syntrophic mechanisms differentiating methanotrophic and methanogenic archaea 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.25.461819v1?rss=1</link>
<description><![CDATA[
The anaerobic oxidation of methane coupled to sulfate reduction is a microbially mediated process requiring a syntrophic partnership between anaerobic methanotrophic (ANME) archaea and sulfate reducing bacteria (SRB). Based on genome taxonomy, ANME lineages are polyphyletic within the phylum Halobacterota, none of which have been isolated in pure culture. Here we reconstruct 28 ANME genomes from environmental metagenomes and flow sorted syntrophic consortia. Together with a reanalysis of previously published datasets, these genomes enable a comparative analysis of all marine ANME clades. We review the genomic features which separate ANME from their methanogenic relatives and identify what differentiates ANME clades. Large multiheme cytochromes and bioenergetic complexes predicted to be involved in novel electron bifurcation reactions are well-distributed and conserved in the ANME archaea, while significant variations in the anabolic C1 pathways exists between clades. Our analysis raises the possibility that methylotrophic methanogenesis may have evolved from a methanotrophic ancestor.
]]></description>
<dc:creator>Chadwick, G. L.</dc:creator>
<dc:creator>Skennerton, C. T.</dc:creator>
<dc:creator>Laso-Perez, R.</dc:creator>
<dc:creator>Leu, A. O.</dc:creator>
<dc:creator>Speth, D. R.</dc:creator>
<dc:creator>Yu, H.</dc:creator>
<dc:creator>Morgan-Lang, C.</dc:creator>
<dc:creator>Hatzenpichler, R.</dc:creator>
<dc:creator>Goudeau, D.</dc:creator>
<dc:creator>Malmstrom, R.</dc:creator>
<dc:creator>Brazelton, W. J.</dc:creator>
<dc:creator>Woyke, T.</dc:creator>
<dc:creator>Hallam, S. J.</dc:creator>
<dc:creator>Tyson, G. W.</dc:creator>
<dc:creator>Wegener, G.</dc:creator>
<dc:creator>Boetius, A.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2021-09-26</dc:date>
<dc:identifier>doi:10.1101/2021.09.25.461819</dc:identifier>
<dc:title><![CDATA[Comparative genomics reveals electron transfer and syntrophic mechanisms differentiating methanotrophic and methanogenic archaea]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.03.462901v1?rss=1">
<title>
<![CDATA[
Optimization of anastomotic technique and gastric conduit perfusion with hyperspectral imaging in an experimental model for minimally invasive esophagectomy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.03.462901v1?rss=1</link>
<description><![CDATA[
ObjectiveTo optimize anastomotic technique and gastric conduit perfusion with hyperspectral imaging (HSI) for total minimally invasive esophagectomy (MIE) with linear stapled anastomosis.

Summary Background DataEsophagectomy is the mainstay of esophageal cancer treatment but anastomotic insufficiency related morbidity and mortality remain challenging for patient outcome.

MethodsA live porcine model (n=50) for MIE was used with gastric conduit formation and linear stapled side-to-side esophagogastrostomy. Four main experimental groups differed in stapling length (3 vs. 6 cm) and anastomotic position on the conduit (cranial vs. caudal). Tissue oxygenation around the anastomotic site was evaluated using HSI and was validated with histopathology.

ResultsThe tissue oxygenation ({Delta}StO2) after the anastomosis remained constant only for the short stapler in caudal position (-0.4{+/-} 4.4%, n.s.) while it dropped markedly in the other groups (short-cranial: -15.6{+/-} 11.5%, p=0.0002; long-cranial: -20.4{+/-} 7.6%, p=0.0126; long-caudal: -16.1{+/-} 9.4%, p<0.0001) Tissue samples from deoxygenated stomach as measured by HSI showed correspondent eosinophilic pre-necrotic changes in 35.7{+/-} 9.7% of the surface area.

ConclusionsTissue oxygenation at the anastomotic site of the gastric conduit during MIE is influenced by stapling technique. Optimal oxygenation was achieved with a short stapler (3 cm) and sufficient distance of the anastomosis to the cranial end of the gastric conduit. HSI tissue deoxygenation corresponded to histopathologic necrotic tissue changes. These findings allow for optimization of gastric conduit perfusion and anastomotic technique in MIE.

Level of EvidenceNot applicable. Translational animal science. Original article.
]]></description>
<dc:creator>Nickel, F.</dc:creator>
<dc:creator>Studier-Fischer, A.</dc:creator>
<dc:creator>Oezdemir, B.</dc:creator>
<dc:creator>Odenthal, J.</dc:creator>
<dc:creator>Mueller, L.-R.</dc:creator>
<dc:creator>Knoedler, S.</dc:creator>
<dc:creator>Kowalewski, K.-F.</dc:creator>
<dc:creator>Camplisson, I.</dc:creator>
<dc:creator>Allers, M. M.</dc:creator>
<dc:creator>Dietrich, M.</dc:creator>
<dc:creator>Schmidt, K.</dc:creator>
<dc:creator>Salg, G. A.</dc:creator>
<dc:creator>Kenngott, H. G.</dc:creator>
<dc:creator>Billeter, A.</dc:creator>
<dc:creator>Gockel, I.</dc:creator>
<dc:creator>Sagiv, C.</dc:creator>
<dc:creator>Etz-Hadar, O.</dc:creator>
<dc:creator>Gildenblat, J.</dc:creator>
<dc:creator>Ayala, L.</dc:creator>
<dc:creator>Seidlitz, S.</dc:creator>
<dc:creator>Maier-Hein, L.</dc:creator>
<dc:creator>Mueller-Stich, B. P.</dc:creator>
<dc:date>2021-10-04</dc:date>
<dc:identifier>doi:10.1101/2021.10.03.462901</dc:identifier>
<dc:title><![CDATA[Optimization of anastomotic technique and gastric conduit perfusion with hyperspectral imaging in an experimental model for minimally invasive esophagectomy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.04.462948v1?rss=1">
<title>
<![CDATA[
Structure of an ant-myrmecophile-microbe community 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.04.462948v1?rss=1</link>
<description><![CDATA[
Superorganismal ant colonies play host to a menagerie of symbiotic arthropods, termed myrmecophiles, which exhibit varying degrees of social integration into colony life. Such systems permit examination of how animal community interactions influence microbial assemblages. Here, we present an ecologically and phylogenetically comprehensive characterization of an ant-myrmecophile-microbe community in Southern California. Using 16S rRNA profiling, we find that microbiotas of the velvety tree ant (Liometopum occidentale) and its cohort of myrmecophiles are distinguished by species-specific characteristics but nevertheless bear signatures of their behavioral interactions. We found that the host ant microbiome was diverse at all taxonomic levels; that of a myrmecophilous cricket was moderately diverse, while microbiotas of three myrmecophilous rove beetles (Staphylinidae), which have convergently evolved symbiosis with Liometopum, were dominated by intracellular endosymbionts. Yet, despite these compositional differences, similarities between ant and myrmecophile microbiotas correlated with the nature and intimacy of their behavioral relationships. Physical interactions such as grooming and trophallaxis likely facilitate cross-species extracellular microbial sharing. Further, phylogenetic comparisons of microbiotas from myrmecophile rove beetles and outgroups revealed a lack of co-cladogenesis of beetles and intracellular endosymbionts, and limited evidence for convergence among the myrmecophiles intracellular microbiotas. Comparative genomic analyses of the dominant Rickettsia endosymbiont of the most highly socially integrated myrmecophile imply possible functions unrelated to nutrient-provisioning in the host beetles specialized lifestyle. Our findings indicate that myrmecophile microbiotas evolve largely independently of the constraints of deep evolutionary history, and that the transition to life inside colonies, including social interactions with hosts, plays a significant role in structuring bacterial assemblages of these symbiotic insects.
]]></description>
<dc:creator>Perry, E. K.</dc:creator>
<dc:creator>Siozios, S.</dc:creator>
<dc:creator>Hurst, G. D. D.</dc:creator>
<dc:creator>Parker, J.</dc:creator>
<dc:date>2021-10-05</dc:date>
<dc:identifier>doi:10.1101/2021.10.04.462948</dc:identifier>
<dc:title><![CDATA[Structure of an ant-myrmecophile-microbe community]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.04.463082v1?rss=1">
<title>
<![CDATA[
Fluorescence Activation Mechanism and Imaging of Drug Permeation with New Sensors for Smoking-Cessation Ligands 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.04.463082v1?rss=1</link>
<description><![CDATA[
Nicotinic partial agonists provide an accepted aid for smoking cessation and thus contribute to decreasing tobacco-related disease. Improved drugs constitute a continued area of study. However, there remains no reductionist method to examine the cellular and subcellular pharmacokinetic properties of these compounds in living cells. Here, we developed new intensity-based drug sensing fluorescent reporters ("iDrugSnFRs") for the nicotinic partial agonists dianicline, cytisine, and two cytisine derivatives - 10-fluorocytisine and 9-bromo-10-ethylcytisine. We report the first atomic-scale structures of liganded periplasmic binding protein-based biosensors, accelerating development of iDrugSnFRs and also explaining the activation mechanism. The nicotinic iDrugSnFRs detect their drug partners in solution, as well as at the plasma membrane (PM) and in the endoplasmic reticulum (ER) of cell lines and mouse hippocampal neurons. At the PM, the speed of solution changes limits the growth and decay rates of the fluorescence response in almost all cases. In contrast, we found that rates of membrane crossing differ among these nicotinic drugs by > 30 fold. The new nicotinic iDrugSnFRs provide insight into the real-time pharmacokinetic properties of nicotinic agonists and provide a methodology whereby iDrugSnFRs can inform both pharmaceutical neuroscience and addiction neuroscience.
]]></description>
<dc:creator>Nichols, A. L.</dc:creator>
<dc:creator>Blumenfeld, Z.</dc:creator>
<dc:creator>Fan, C.</dc:creator>
<dc:creator>Luebbert, L.</dc:creator>
<dc:creator>Blom, A. E. M.</dc:creator>
<dc:creator>Cohen, B. N.</dc:creator>
<dc:creator>Marvin, J. S.</dc:creator>
<dc:creator>Borden, P. M.</dc:creator>
<dc:creator>Kim, C.</dc:creator>
<dc:creator>Muthusamy, A. K.</dc:creator>
<dc:creator>Shivange, A. V.</dc:creator>
<dc:creator>Knox, H. J.</dc:creator>
<dc:creator>Campello, H. R.</dc:creator>
<dc:creator>Wang, J. H.</dc:creator>
<dc:creator>Dougherty, D. A.</dc:creator>
<dc:creator>Looger, L.</dc:creator>
<dc:creator>Gallagher, T.</dc:creator>
<dc:creator>Rees, D. C.</dc:creator>
<dc:creator>Lester, H. A.</dc:creator>
<dc:date>2021-10-04</dc:date>
<dc:identifier>doi:10.1101/2021.10.04.463082</dc:identifier>
<dc:title><![CDATA[Fluorescence Activation Mechanism and Imaging of Drug Permeation with New Sensors for Smoking-Cessation Ligands]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.04.463088v1?rss=1">
<title>
<![CDATA[
Video-evoked fMRI BOLD responses are highly consistent across different data acquisition sites 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.04.463088v1?rss=1</link>
<description><![CDATA[
Naturalistic imaging paradigms, in which participants view complex videos in the scanner, are increasingly used in human cognitive neuroscience. Videos evoke temporally synchronized brain responses that are similar across subjects as well as within subjects, but the reproducibility of these brain responses across different data acquisition sites has not yet been quantified. Here we characterize the consistency of brain responses across independent samples of participants viewing the same videos in fMRI scanners at different sites (Indiana University and Caltech). We compared brain responses collected at these different sites for two carefully matched datasets with identical scanner models, acquisition, and preprocessing details, along with a third unmatched dataset in which these details varied. Our overall conclusion is that for matched and unmatched datasets alike, video-evoked brain responses have high consistency across these different sites, both when compared across groups and across pairs of individuals. As one might expect, differences between sites were larger for unmatched datasets than matched datasets. Residual differences between datasets could in part reflect participant-level variability rather than scanner- or data-related effects. Altogether our results indicate promise for the development and, critically, generalization of video fMRI studies of individual differences in healthy and clinical populations alike.
]]></description>
<dc:creator>Byrge, L.</dc:creator>
<dc:creator>Kliemann, D.</dc:creator>
<dc:creator>He, Y.</dc:creator>
<dc:creator>Cheng, H.</dc:creator>
<dc:creator>Tyszka, J. M.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:creator>Kennedy, D. P.</dc:creator>
<dc:date>2021-10-05</dc:date>
<dc:identifier>doi:10.1101/2021.10.04.463088</dc:identifier>
<dc:title><![CDATA[Video-evoked fMRI BOLD responses are highly consistent across different data acquisition sites]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.06.463315v1?rss=1">
<title>
<![CDATA[
Large-scale comparative genomics unravels great genomic diversity across the Rickettsia and Ca. Megaira genera and identifies Torix group as an evolutionarily distinct clade. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.06.463315v1?rss=1</link>
<description><![CDATA[
Rickettsia are intracellular bacteria originally described as arthropod borne pathogens that are emerging as a diverse group of often biologically important, non-pathogenic symbionts of invertebrates and microeukaryotes. However, sparse genomic resources for symbiotic strains and for the sister genus (Candidatus Megaira) inhibit our understanding of Rickettsia evolution and biology. Here, we present the first closed genomes of Ca. Megaira from an alga (Mesostigma viride), and Torix Rickettsia from midge (Culicoides impunctatus) and bed bug (Cimex lectularius) hosts. Additionally, we sequenced and constructed draft genomes for Ca. Megaira from another alga (Carteria cerasiformis), Transitional group Rickettsia from tsetse fly (Glossina morsitans submorsitans), and Torix Rickettsia from a spider mite (Bryobia graminum). We further extract 22 draft genomes from arthropod genome sequencing projects, including 1 Adalia, 4 Transitional, 1 Spotted Fever, 7 Torix, 7 Belli and the first Rhyzobius and Meloidae Rickettsia group genomes. We used new and existing Rickettsia genomes to estimate the phylogeny and metabolic potential across groups and reveal transitions in genomic properties. These data reveal Torix as unique amongst currently described Rickettsia, with highly distinct and diverse accessory genomes. We confirm the presence of a third subclade of Torix, previously only known from gene marker sequences. Further, Torix share an intact pentose phosphate pathway with Ca. Megaira, not observed in other Rickettsia. Considering the distinctness and diversity of Torix, we propose that the group be named Candidatus Tisiphia. The wide host range of Ca. Tisiphia symbionts necessitates onward research to understand the biological and physiological bases of Ca. Tisiphia-host interactions.

Importance statementMembers of the genus Rickettsia were originally identified as causative agents of mammalian vector-borne disease. In the last 25 years we have recognised that many Rickettsia are arthropod symbionts, and sit alongside a sister taxon, Ca. Megaira, which are symbiotic associates of microeukaryotes. The lack of genomic information for symbiotic strains affects our ability to determine the evolutionary relationships between strains and understand the biological underpinnings of the different symbioses. We clarify these relationships by assembling 26 genomes of Rickettsia from understudied groups, and the first two Ca. Megaira, from various insects and microeukaryotes. Of note, the accessory genome diversity and broad host range of Torix Rickettsia parallels all other Rickettsia combined. This diversity, alongside the breadth of host species, make the Torix clade an important hidden player in invertebrate biology and physiology. We argue this clade should be given its own genus status, for which we propose Ca. Tisiphia.
]]></description>
<dc:creator>Davison, H. R.</dc:creator>
<dc:creator>Pilgrim, J.</dc:creator>
<dc:creator>Wybouw, N.</dc:creator>
<dc:creator>Parker, J.</dc:creator>
<dc:creator>Pirro, S.</dc:creator>
<dc:creator>Hunter-Barnett, S.</dc:creator>
<dc:creator>Campbell, P. M.</dc:creator>
<dc:creator>Blow, F.</dc:creator>
<dc:creator>Darby, A. C.</dc:creator>
<dc:creator>Hurst, G. D. D.</dc:creator>
<dc:creator>Siozios, S.</dc:creator>
<dc:date>2021-10-06</dc:date>
<dc:identifier>doi:10.1101/2021.10.06.463315</dc:identifier>
<dc:title><![CDATA[Large-scale comparative genomics unravels great genomic diversity across the Rickettsia and Ca. Megaira genera and identifies Torix group as an evolutionarily distinct clade.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.07.463105v1?rss=1">
<title>
<![CDATA[
Preserved motor representations after paralysis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.07.463105v1?rss=1</link>
<description><![CDATA[
AO_SCPLOWBSTRACTC_SCPLOWNeural plasticity allows us to learn skills and incorporate new experiences. What happens when our lived experiences fundamentally change, such as after a severe injury? To address this question, we analyzed intracortical population activity in a tetraplegic adult as she controlled a virtual hand through a brain-computer interface (BCI). By attempting to move her fingers, she could accurately drive the corresponding virtual fingers. Neural activity during finger movements exhibited robust representational structure and dynamics that matched the representational structure, previously identified in able-bodied individuals. The finger representational structure was consistent during extended use, even though the structure contributed to BCI decoding errors. Our results suggest that motor representations are remarkably stable, even after complete paralysis. BCIs re-engage these preserved representations to restore lost motor functions.
]]></description>
<dc:creator>Guan, C.</dc:creator>
<dc:creator>Aflalo, T.</dc:creator>
<dc:creator>Zhang, C.</dc:creator>
<dc:creator>Rosario, E. R.</dc:creator>
<dc:creator>Pouratian, N.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2021-10-09</dc:date>
<dc:identifier>doi:10.1101/2021.10.07.463105</dc:identifier>
<dc:title><![CDATA[Preserved motor representations after paralysis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.07.463215v1?rss=1">
<title>
<![CDATA[
3D imaging for the quantification of spatial patterns in microbiota of the intestinal mucosa 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.07.463215v1?rss=1</link>
<description><![CDATA[
Improving our understanding of host-microbe relationships in the gut requires the ability to both visualize and quantify the spatial organization of microbial communities in their native orientation with the host tissue. We developed a systematic procedure to quantify the 3D spatial structure of the native mucosal microbiota in any part of the intestines with taxonomic and high spatial resolution. We performed a 3D biogeographical analysis of the microbiota of mouse cecal crypts at different stages of antibiotic exposure. By tracking eubacteria and four dominant bacterial taxa, we found that the colonization of crypts by native bacteria is a dynamic and spatially organized process. Ciprofloxacin treatment drastically reduced bacterial loads and eliminated Muribaculaceae (or all Bacteroidetes entirely) even 10 days after recovery when overall bacterial loads returned to pre-antibiotic levels. Our 3D quantitative imaging approach revealed that the bacterial colonization of crypts is organized in a spatial pattern that consists of clusters of adjacent colonized crypts that are surrounded by unoccupied crypts, and that this spatial pattern was resistant to the elimination of Muribaculaceae or of all Bacteroidetes by ciprofloxacin. Our approach also revealed that the composition of cecal crypt communities is diverse and that bacterial taxa are distributed differently within crypts, with Lactobacilli laying closer to the lumen than Bacteroidetes, Ruminococcaceae, and Lachnospiraceae. Finally, we found that crypts communities with similar taxonomic composition were physically closer to each other than communities that were taxonomically different.

Significance StatementMany human diseases are causally linked to the gut microbiota, yet the field still lacks mechanistic understanding of the underlying complex interactions because existing tools cannot simultaneously quantify microbial communities and their intact native context. In this work, we provide a new approach to tissue clearing and preservation that enables visualization, in 3D and at scales ranging from centimeters to micrometers, of the complete biogeography of the host-microbiota interface. We combine this new tool with sequencing and multiplexed labelling of the microbiota to provide the field with a platform on which to discover patterns in the spatial distribution of microbes. We validated this platform by quantifying the distribution of bacteria in the cecal mucosa at different stages of antibiotic exposure. This approach will enable researchers to formulate and test new hypotheses about host-microbe and microbe-microbe interactions.
]]></description>
<dc:creator>Mondragon-Palomino, O.</dc:creator>
<dc:creator>Poceviciute, R.</dc:creator>
<dc:creator>Lignell, A.</dc:creator>
<dc:creator>Griffiths, J. A.</dc:creator>
<dc:creator>Takko, H.</dc:creator>
<dc:creator>Ismagilov, R. F.</dc:creator>
<dc:date>2021-10-08</dc:date>
<dc:identifier>doi:10.1101/2021.10.07.463215</dc:identifier>
<dc:title><![CDATA[3D imaging for the quantification of spatial patterns in microbiota of the intestinal mucosa]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.07.463289v1?rss=1">
<title>
<![CDATA[
A Systematic Interrogation of MHC Class I Antigen Presentation Identifies Constitutive and Compensatory Protein Degradation Pathways 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.07.463289v1?rss=1</link>
<description><![CDATA[
The adaptive immune system distinguishes self from non-self by surveying peptides generated from degradation of intracellular proteins that are loaded onto MHC Class I molecules for display on the cell surface. While early studies reported that the bulk of cell surface MHC Class I complexes require the ubiquitin-proteasome system (UPS) for their generation, this conclusion has been challenged. To better understand MHC Class I peptide origins, we sought to carry out a comprehensive, quantitative census of the MHC Class I peptide repertoire in the presence and absence of UPS activity. We introduce optimized methodology to enrich for authentic Class I-bound peptides in silico and then quantify by mass spectrometry their relative amounts upon perturbation of the ubiquitin-proteasome system. Whereas most peptides are dependent on the proteasome and ubiquitination for their generation, a surprising 30% of the MHC Class I repertoire, enriched in peptides of mitochondrial origin, appears independent of these pathways. A further [~]10% of Class I-bound peptides were found to be dependent on the proteasome but independent of ubiquitination for their generation. Notably, clinically achievable partial inhibition of the proteasome resulted in display of novel peptides antigens, at least one of which promotes immune system activation. Our results suggest that generation of MHC Class I*peptide complexes is more complex than previously recognized and also provide evidence for compensatory peptide-generating pathways when canonical pathways are impaired.
]]></description>
<dc:creator>Mamrosh, J. L.</dc:creator>
<dc:creator>Li, J.</dc:creator>
<dc:creator>Sherman, D. J.</dc:creator>
<dc:creator>Moradian, A.</dc:creator>
<dc:creator>Sweredoski, M. J.</dc:creator>
<dc:creator>Verma, R.</dc:creator>
<dc:creator>Johnston, J. A.</dc:creator>
<dc:creator>Lipford, J. R.</dc:creator>
<dc:creator>Deshaies, R. J.</dc:creator>
<dc:date>2021-10-08</dc:date>
<dc:identifier>doi:10.1101/2021.10.07.463289</dc:identifier>
<dc:title><![CDATA[A Systematic Interrogation of MHC Class I Antigen Presentation Identifies Constitutive and Compensatory Protein Degradation Pathways]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.09.463779v1?rss=1">
<title>
<![CDATA[
Intelligent Resolution: Integrating Cryo-EM with AI-driven Multi-resolution Simulations to Observe the SARS-CoV-2 Replication-Transcription Machinery in Action 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.09.463779v1?rss=1</link>
<description><![CDATA[
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) replication transcription complex (RTC) is a multi-domain protein responsible for replicating and transcribing the viral mRNA inside a human cell. Attacking RTC function with pharmaceutical compounds is a pathway to treating COVID-19. Conventional tools, e.g., cryo-electron microscopy and all-atom molecular dynamics (AAMD), do not provide sufficiently high resolution or timescale to capture important dynamics of this molecular machine. Consequently, we develop an innovative workflow that bridges the gap between these resolutions, using mesoscale fluctuating finite element analysis (FFEA) continuum simulations and a hierarchy of AI-methods that continually learn and infer features for maintaining consistency between AAMD and FFEA simulations. We leverage a multi-site distributed workflow manager to orchestrate AI, FFEA, and AAMD jobs, providing optimal resource utilization across HPC centers. Our study provides unprecedented access to study the SARS-CoV-2 RTC machinery, while providing general capability for AI-enabled multi-resolution simulations at scale.
]]></description>
<dc:creator>Trifan, A.</dc:creator>
<dc:creator>Gorgun, D.</dc:creator>
<dc:creator>Li, Z.</dc:creator>
<dc:creator>Brace, A.</dc:creator>
<dc:creator>Zvyagin, M.</dc:creator>
<dc:creator>Ma, H.</dc:creator>
<dc:creator>Clyde, A. R.</dc:creator>
<dc:creator>Clark, D. A.</dc:creator>
<dc:creator>Salim, M.</dc:creator>
<dc:creator>Hardy, D.</dc:creator>
<dc:creator>Burnley, T.</dc:creator>
<dc:creator>Huang, L.</dc:creator>
<dc:creator>McCalpin, J.</dc:creator>
<dc:creator>Emani, M.</dc:creator>
<dc:creator>Yoo, H.</dc:creator>
<dc:creator>Yin, J.</dc:creator>
<dc:creator>Tsaris, A.</dc:creator>
<dc:creator>Subbiah, V.</dc:creator>
<dc:creator>Liu, J.</dc:creator>
<dc:creator>Trebesch, N.</dc:creator>
<dc:creator>Wells, G.</dc:creator>
<dc:creator>Mysore, V.</dc:creator>
<dc:creator>Gibbs, T.</dc:creator>
<dc:creator>Phillips, J.</dc:creator>
<dc:creator>Chennubhotla, S. C.</dc:creator>
<dc:creator>Foster, I.</dc:creator>
<dc:creator>Stevens, R.</dc:creator>
<dc:creator>Anandkumar, A.</dc:creator>
<dc:creator>Vishwanath, V.</dc:creator>
<dc:creator>Stone, J. E.</dc:creator>
<dc:creator>Tajkhorshid, E.</dc:creator>
<dc:creator>Harris, S. A.</dc:creator>
<dc:creator>Ramanathan, A.</dc:creator>
<dc:date>2021-10-12</dc:date>
<dc:identifier>doi:10.1101/2021.10.09.463779</dc:identifier>
<dc:title><![CDATA[Intelligent Resolution: Integrating Cryo-EM with AI-driven Multi-resolution Simulations to Observe the SARS-CoV-2 Replication-Transcription Machinery in Action]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.13.464279v1?rss=1">
<title>
<![CDATA[
Novelty and uncertainty interact to regulate the balance between exploration and exploitation in the human brain. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.13.464279v1?rss=1</link>
<description><![CDATA[
Recent evidence suggests that both novelty and uncertainty act as potent features guiding exploration. However, these variables are often conflated with each other experimentally, and an understanding of how these attributes interact to regulate the balance between exploration and exploitation has proved elusive. Using a novel task designed to decouple stimulus novelty and estimation uncertainty, we identify separable behavioral and neural mechanisms by which exploration is colored. We show that uncertainty was avoided except when the information gained through exploration could be reliably exploited in the future. In contrast, and contrary to existing theory, novel options grew increasingly attractive relative to familiar counterparts irrespective of the opportunity to leverage their consequences and despite the uncertainty inherent to novel options. These findings led us to develop a formal computational framework in which uncertainty directed choice adapts to the prospective utility of exploration, while novel stimuli persistently draw favor as a result of inflated reward expectations biasing an exploitative strategy. Crucially, novelty is proposed to actively modulate uncertainty processing, effectively blunting the influence of uncertainty in shaping the subjective utility ascribed to novel stimuli. Both behavioral data and fMRI activity sampled from the ventromedial prefrontal cortex, frontopolar cortex and ventral striatum validate this model, thereby establishing a computational account that can not only explain behavior but also shed light on the functional contribution of these key brain regions to the exploration/exploitation trade-off. Our results point to multiple strategies and neural substrates charged with balancing the explore/exploit dilemma, with each targeting distinct aspects of the decision problem to foster a manageable decomposition of an otherwise intractable task.
]]></description>
<dc:creator>Cockburn, J.</dc:creator>
<dc:creator>Man, V.</dc:creator>
<dc:creator>Cunningham, W. A.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:date>2021-10-14</dc:date>
<dc:identifier>doi:10.1101/2021.10.13.464279</dc:identifier>
<dc:title><![CDATA[Novelty and uncertainty interact to regulate the balance between exploration and exploitation in the human brain.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.15.464467v1?rss=1">
<title>
<![CDATA[
Diversity and evolution of nitric oxide reduction 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.15.464467v1?rss=1</link>
<description><![CDATA[
Nitrogen is an essential element for life, with the availability of fixed nitrogen limiting productivity in many ecosystems. The return of oxidized nitrogen species to the atmospheric N2 pool is predominately catalyzed by microbial denitrification (NO3- [-&gt;] NO2- [-&gt;] NO [-&gt;] N2O [-&gt;] N2)1. Incomplete denitrification can produce N2O as a terminal product, leading to an increase in atmospheric N2O, a potent greenhouse and ozone-depleting gas2. The production of N2O is catalyzed by nitric oxide reductase (NOR) members of the heme-copper oxidoreductase (HCO) superfamily3. Here we use phylogenomics to identify a number of previously uncharacterized HCO families and propose that many of them (eNOR, sNOR, gNOR, and nNOR) perform nitric oxide reduction. These families have novel active-site structures and several have conserved proton channels, suggesting that they might be able to couple nitric oxide reduction to energy conservation. We isolated and biochemically characterized a member of the eNOR family from Rhodothermus marinus, verifying that it performs nitric oxide reduction both in vitro and in vivo. These newly identified NORs exhibit broad phylogenetic and environmental distributions, expanding the diversity of microbes that can perform denitrification. Phylogenetic analyses of the HCO superfamily demonstrate that nitric oxide reductases evolved multiple times independently from oxygen reductases, suggesting that complete denitrification evolved after aerobic respiration.
]]></description>
<dc:creator>Hemp, J.</dc:creator>
<dc:creator>Murali, R.</dc:creator>
<dc:creator>Pace, L. A.</dc:creator>
<dc:creator>Sanford, R. A.</dc:creator>
<dc:creator>Hatzenpichler, R.</dc:creator>
<dc:creator>Ward, L.</dc:creator>
<dc:creator>Lingappa, U.</dc:creator>
<dc:creator>Fischer, W. W.</dc:creator>
<dc:creator>Gennis, R. B.</dc:creator>
<dc:date>2021-10-15</dc:date>
<dc:identifier>doi:10.1101/2021.10.15.464467</dc:identifier>
<dc:title><![CDATA[Diversity and evolution of nitric oxide reduction]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.18.464444v1?rss=1">
<title>
<![CDATA[
Protease-controlled secretion and display of intercellular signals 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.18.464444v1?rss=1</link>
<description><![CDATA[
To program intercellular communication for biomedicine, it is crucial to regulate the secretion and surface display of signaling proteins. If such regulations are at the protein level, there are additional advantages, including compact delivery and direct interactions with endogenous signalling pathways. We created a modular, generalizable design called Retained Endoplasmic Cleavable Secretion (RELEASE), with engineered proteins retained in the endoplasmic reticulum and displayed/secreted in response to specific proteases. The design allows functional regulation of multiple synthetic and natural proteins by synthetic protease circuits to realize diverse signal processing capabilities, including logic operation and threshold tuning. By linking RELEASE to additional novel sensing and processing circuits, we were able to achieve elevated protein secretion in response to "undruggable" oncogene KRAS mutants. RELEASE should enable the local, programmable delivery of intercellular cues for a broad variety of fields such as neurobiology, cancer immunotherapy and cell transplantation.
]]></description>
<dc:creator>Vlahos, A. E.</dc:creator>
<dc:creator>Kang, J.</dc:creator>
<dc:creator>Aldrete, C. A.</dc:creator>
<dc:creator>Zhu, R.</dc:creator>
<dc:creator>Chong, L. S.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:creator>Gao, X. J.</dc:creator>
<dc:date>2021-10-19</dc:date>
<dc:identifier>doi:10.1101/2021.10.18.464444</dc:identifier>
<dc:title><![CDATA[Protease-controlled secretion and display of intercellular signals]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.21.464743v1?rss=1">
<title>
<![CDATA[
Commensal bacteria promote type I interferon signaling to maintain immune tolerance 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.21.464743v1?rss=1</link>
<description><![CDATA[
Type I interferons (IFN) exert a broad range of biological effects important in coordinating immune responses. Host and microbial factors regulate IFN production, triggering a signaling cascade that has classically been studied in the context of pathogen clearance. In particular, commensal bacteria have been shown to induce IFN to protect against viral infections. Yet, whether immunomodulatory bacteria operate through IFN pathways to support immune tolerance remains elusive. Here, we demonstrate microbiota-dependent IFN signaling is required for priming tolerogenic T regulatory cells (Tregs) by intestinal dendritic cells (DCs). DCs deficient in IFN signaling through deletion of IFNAR-1 display dysregulated cytokine production in response to the commensal bacteria Bacteroides fragilis, resulting in blunted downstream Treg responses. Single cell RNA sequencing of gut tissues demonstrated that colonization with B. fragilis promotes a distinct type I IFN gene signature in Tregs during homeostasis and intestinal inflammation. Moreover, B. fragilis-mediated protection during experimental colitis was abrogated in IFNAR1-deficient mice. Altogether, our findings demonstrate an important role of microbiota-mediated immune tolerance via tonic type I IFN signaling.
]]></description>
<dc:creator>Vasquez Ayala, A.</dc:creator>
<dc:creator>Matsuo, K.</dc:creator>
<dc:creator>Hsu, C.-Y.</dc:creator>
<dc:creator>Carrillo Terrazas, M.</dc:creator>
<dc:creator>Chu, H.</dc:creator>
<dc:date>2021-10-21</dc:date>
<dc:identifier>doi:10.1101/2021.10.21.464743</dc:identifier>
<dc:title><![CDATA[Commensal bacteria promote type I interferon signaling to maintain immune tolerance]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.26.465790v1?rss=1">
<title>
<![CDATA[
Architecture of the cytoplasmic face of the nuclear pore 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.26.465790v1?rss=1</link>
<description><![CDATA[
The nuclear pore complex (NPC) is the sole bidirectional gateway for nucleocytoplasmic transport. Despite recent progress in elucidating the NPC symmetric core architecture, the asymmetrically decorated cytoplasmic face, essential for mRNA export and a hotspot for nucleoporin-associated diseases, has remained elusive. Here, we report a composite structure of the entire human cytoplasmic face obtained by combining biochemical reconstitution, crystal structure determination, docking into cryo-electron tomographic reconstructions, and physiological validation, accounting for a third of the NPCs mass. Whereas an evolutionarily conserved [~]540 kDa hetero-hexameric cytoplasmic filament nucleoporin complex is anchored by species-specific motifs above the central transport channel, attachment of the pentameric NUP358 bundles depends on the double-ring arrangement of the coat nucleoporin complex. Our results and the predictive power of our composite structure provide a rich foundation for elucidating the molecular basis of mRNA export and nucleoporin diseases.

One sentence summaryAn interdisciplinary analysis established the near-atomic molecular architecture of the cytoplasmic face of the human nuclear pore complex.
]]></description>
<dc:creator>Bley, C. J.</dc:creator>
<dc:creator>Nie, S.</dc:creator>
<dc:creator>Mobbs, G.</dc:creator>
<dc:creator>Petrovic, S.</dc:creator>
<dc:creator>Gres, A.</dc:creator>
<dc:creator>Liu, X.</dc:creator>
<dc:creator>Mukherjee, S.</dc:creator>
<dc:creator>Harvey, S.</dc:creator>
<dc:creator>Huber, F. M.</dc:creator>
<dc:creator>Lin, D. H.</dc:creator>
<dc:creator>Brown, B.</dc:creator>
<dc:creator>Tang, A. W.</dc:creator>
<dc:creator>Rundlet, E. J.</dc:creator>
<dc:creator>Correia, A. R.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Regmi, S. G.</dc:creator>
<dc:creator>Dasso, M.</dc:creator>
<dc:creator>Patke, A.</dc:creator>
<dc:creator>Palazzo, A. F.</dc:creator>
<dc:creator>Kossiakoff, A. A.</dc:creator>
<dc:creator>Hoelz, A.</dc:creator>
<dc:date>2021-10-26</dc:date>
<dc:identifier>doi:10.1101/2021.10.26.465790</dc:identifier>
<dc:title><![CDATA[Architecture of the cytoplasmic face of the nuclear pore]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.26.465796v1?rss=1">
<title>
<![CDATA[
Architecture of the linker-scaffold in the nuclear pore 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.26.465796v1?rss=1</link>
<description><![CDATA[
The nuclear pore complex (NPC) is the sole bidirectional gateway for nucleocytoplasmic transport. Despite recent progress in elucidating the arrangement of the structured scaffold building blocks in the NPC symmetric core, their cohesion by multivalent unstructured linker proteins remained elusive. Combining biochemical reconstitution, high resolution structure determination, docking into cryo-electron tomographic reconstructions, and physiological validation, we elucidated the architecture of the entire linker-scaffold, yielding a near-atomic composite structure of the symmetric core accounting for [~]77 MDa of the human NPC. Whereas linkers generally play a rigidifying role, the linker-scaffold of the NPC provides the plasticity and robustness necessary for the reversible constriction and dilation of its central transport channel. Our results complete the structural characterization of the NPC symmetric core, providing a rich foundation for future functional studies.

One sentence summaryAn interdisciplinary analysis established the near-atomic molecular architecture and evolutionary conservation of the linker-scaffold of the human nuclear pore complex.
]]></description>
<dc:creator>Petrovic, S.</dc:creator>
<dc:creator>Samanta, D.</dc:creator>
<dc:creator>Perriches, T.</dc:creator>
<dc:creator>Bley, C. J.</dc:creator>
<dc:creator>Thierbach, K.</dc:creator>
<dc:creator>Brown, B.</dc:creator>
<dc:creator>Nie, S.</dc:creator>
<dc:creator>Mobbs, G. W.</dc:creator>
<dc:creator>Stevens, T. A.</dc:creator>
<dc:creator>Liu, X.</dc:creator>
<dc:creator>Hoelz, A.</dc:creator>
<dc:date>2021-10-26</dc:date>
<dc:identifier>doi:10.1101/2021.10.26.465796</dc:identifier>
<dc:title><![CDATA[Architecture of the linker-scaffold in the nuclear pore]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.26.465928v1?rss=1">
<title>
<![CDATA[
Transcriptomic profiling of sex-specific olfactory neurons reveals subset-specific receptor expression in C. elegans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.26.465928v1?rss=1</link>
<description><![CDATA[
SummaryThe nematode Caenorhabditis elegans utilizes chemosensation to navigate an ever-changing environment for its survival. A class of secreted small-molecule pheromones, termed ascarosides, play an important role in olfactory perception by affecting biological functions ranging from development to behavior. The ascaroside ascr#8 mediates sex-specific behaviors, driving avoidance in hermaphrodites and attraction in males. Males sense ascr#8 via the ciliated male-specific cephalic sensory (CEM) neurons, which exhibit radial symmetry along dorsal-ventral and left-right axes. Calcium imaging studies suggest a complex neural coding mechanism that translates stochastic physiological responses in these neurons to reliable behavioral outputs. To test the hypothesis that neurophysiological complexity arises from differential expression of genes, we performed cell-specific transcriptomic profiling; this revealed between 18 and 62 genes with at least two-fold higher expression in a specific CEM neuron type versus both other CEM neurons and adult males. These included two G protein coupled receptor (GPCR) genes, srw-97 and dmsr-12, that were specifically expressed in non-overlapping subsets of CEM neurons and whose expression was confirmed by GFP reporter analysis. Single CRISPR-Cas9 knockouts of either srw-97 or dmsr-12 resulted in partial defects, while a double knockout of both srw-97 and dmsr-12 completely abolished the attractive response to ascr#8. Together, our results suggest that the evolutionarily distinct GPCRs SRW-97 and DMSR-12 act non-redundantly in discrete olfactory neurons to facilitate male-specific sensation of ascr#8.
]]></description>
<dc:creator>Reilly, D. K.</dc:creator>
<dc:creator>Schwarz, E. M.</dc:creator>
<dc:creator>Muirhead, C. S.</dc:creator>
<dc:creator>Robidoux, A. N.</dc:creator>
<dc:creator>Antoscheckin, I.</dc:creator>
<dc:creator>Narayan, A.</dc:creator>
<dc:creator>Doma, M.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Srinivasan, J.</dc:creator>
<dc:date>2021-10-28</dc:date>
<dc:identifier>doi:10.1101/2021.10.26.465928</dc:identifier>
<dc:title><![CDATA[Transcriptomic profiling of sex-specific olfactory neurons reveals subset-specific receptor expression in C. elegans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.27.466000v1?rss=1">
<title>
<![CDATA[
Neurons in human pre-supplementary motor area encode key computations for value-based choice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.27.466000v1?rss=1</link>
<description><![CDATA[
Adaptive behavior in real-world environments demands that choices integrate over several variables, including the novelty of the options under consideration, their expected value, and uncertainty in value estimation. We recorded neurons from the human pre-supplementary motor area (preSMA), ventromedial prefrontal cortex (vmPFC) and dorsal anterior cingulate to probe how integration over decision variables occurs during decision-making. In contrast to the other areas, preSMA neurons not only represented separate pre-decision variables for each choice option, but also encoded an integrated utility signal and, subsequently, the decision itself. Conversely, post-decision related encoding of variables for the chosen option was more widely distributed and especially prominent in vmPFC. Our findings position the human preSMA as central to the implementation of value-based decisions.
]]></description>
<dc:creator>Aquino, T. G.</dc:creator>
<dc:creator>Cockburn, J.</dc:creator>
<dc:creator>Mamelak, A. N.</dc:creator>
<dc:creator>Rutishauser, U.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:date>2021-10-28</dc:date>
<dc:identifier>doi:10.1101/2021.10.27.466000</dc:identifier>
<dc:title><![CDATA[Neurons in human pre-supplementary motor area encode key computations for value-based choice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.27.466149v1?rss=1">
<title>
<![CDATA[
Xist spatially amplifies SHARP recruitment to balance chromosome-wide silencing and specificity to the X chromosome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.27.466149v1?rss=1</link>
<description><![CDATA[
Although thousands of lncRNAs are encoded in mammalian genomes, their mechanisms of action are largely uncharacterized because they are often expressed at significantly lower levels than their proposed targets. One such lncRNA is Xist, which mediates chromosome-wide gene silencing on one of the two X chromosomes to achieve gene expression balance between males and females. How a limited number of Xist molecules can mediate robust silencing of a significantly larger number of target genes ([~]1 Xist RNA: 10 gene targets) while maintaining specificity to genes on the X within each cell is unknown. Here, we show that Xist drives non-stoichiometric recruitment of the essential silencing protein SHARP (also called Spen) to amplify its abundance across the inactive X, including at regions not directly occupied by Xist. This amplification is achieved through concentration-dependent homotypic assemblies of SHARP on the X and is required for chromosome-wide silencing. We find that expressing Xist at higher levels leads to increased localization at autosomal regions, demonstrating that low levels of Xist are critical for ensuring its specificity to the X chromosome. We show that Xist (through SHARP) acts to suppress production of its own RNA which may act to constrain overall RNA levels and restrict its ability to spread beyond the X. Together, our results demonstrate a spatial amplification mechanism that allows Xist to achieve two essential but countervailing regulatory objectives: chromosome-wide gene silencing and specificity to the X. Our results suggest that this spatial amplification mechanism may be a more general mechanism by which other low abundance lncRNAs can balance specificity to, and robust control of, their regulatory targets.
]]></description>
<dc:creator>Jachowicz, J. W.</dc:creator>
<dc:creator>Strehle, M.</dc:creator>
<dc:creator>Banerjee, A. K.</dc:creator>
<dc:creator>Blanco, M. R.</dc:creator>
<dc:creator>Thai, J.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:date>2021-10-28</dc:date>
<dc:identifier>doi:10.1101/2021.10.27.466149</dc:identifier>
<dc:title><![CDATA[Xist spatially amplifies SHARP recruitment to balance chromosome-wide silencing and specificity to the X chromosome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.28.466194v1?rss=1">
<title>
<![CDATA[
GATA4 regionalizes intestinal metabolism and barrier function to prevent immunopathology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.28.466194v1?rss=1</link>
<description><![CDATA[
Different regions of the gastrointestinal tract have distinct digestive and absorptive functions, which may be locally disrupted by infection or autoimmune disease. Yet, the mechanisms underlying intestinal regionalization and its dysregulation in disease are not well understood. Here, we used mouse models, transcriptomics, and immune profiling to show that regional epithelial expression of the transcription factor GATA4 prevented adherent bacterial colonization and inflammation in the proximal small intestine by regulating retinol metabolism and luminal IgA. Loss of epithelial GATA4 expression increased mortality in mice infected with Citrobacter rodentium. In active celiac patients with villous atrophy, low GATA4 expression was associated with metabolic alterations, mucosal Actinobacillus, and increased IL-17 immunity. This study reveals broad impacts of GATA4-regulated intestinal regionalization and highlights an elaborate interdependence of intestinal metabolism, immunity, and microbiota in homeostasis and disease.

One-sentence summaryEpithelial GATA4 regulates intestinal regionalization of bacterial colonization, metabolic pathways, and tissue immunity.
]]></description>
<dc:creator>Earley, Z. M.</dc:creator>
<dc:creator>Lisicka, W.</dc:creator>
<dc:creator>Sifakis, J. J.</dc:creator>
<dc:creator>Gamboa, R. A.</dc:creator>
<dc:creator>Kowalczyk, A.</dc:creator>
<dc:creator>Barlow, J.</dc:creator>
<dc:creator>Shaw, D. G.</dc:creator>
<dc:creator>Discepolo, V.</dc:creator>
<dc:creator>Tan, I. L.</dc:creator>
<dc:creator>Gona, S.</dc:creator>
<dc:creator>Ernest, J.</dc:creator>
<dc:creator>Matzinger, P.</dc:creator>
<dc:creator>Barreiro, L. B.</dc:creator>
<dc:creator>Morgun, A.</dc:creator>
<dc:creator>Bendelac, A.</dc:creator>
<dc:creator>Ismagilov, R. F.</dc:creator>
<dc:creator>Shulzhenko, N.</dc:creator>
<dc:creator>Riesenfeld, S. J.</dc:creator>
<dc:creator>Jabri, B.</dc:creator>
<dc:date>2021-10-28</dc:date>
<dc:identifier>doi:10.1101/2021.10.28.466194</dc:identifier>
<dc:title><![CDATA[GATA4 regionalizes intestinal metabolism and barrier function to prevent immunopathology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.28.466356v1?rss=1">
<title>
<![CDATA[
Elevated Hoxb5b expands vagal neural crest pool and blocks enteric neuronal development in zebrafish 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.28.466356v1?rss=1</link>
<description><![CDATA[
Neural crest cells (NCCs) are a migratory, transient, and multipotent stem cell population essential to vertebrate embryonic development, contributing to numerous cell lineages in the adult organism. While great strides have been made in elucidating molecular and cellular events that drive NCC specification, comprehensive knowledge of the genetic factors that orchestrate NCC developmental programs is still far from complete. We discovered that elevated Hoxb5b levels promoted an expansion of zebrafish NCCs, which persisted throughout multiple stages of development. Correspondingly, elevated Hoxb5b also specifically expanded expression domains of the vagal NCC markers foxd3 and phox2bb. Increases in NCCs were most apparent after pulsed ectopic Hoxb5b expression at early developmental stages, rather than later during differentiation stages, as determined using a novel transgenic zebrafish line. The increase in vagal NCCs early in development led to supernumerary Phox2b+ enteric neural progenitors, while leaving many other NCC-derived tissues without an overt phenotype. Surprisingly, these NCC-derived enteric progenitors failed to expand properly into sufficient quantities of enterically fated neurons and stalled in the gut tissue. These results suggest that while Hoxb5b participates in vagal NCC development as a driver of progenitor expansion, the supernumerary, ectopically localized NCC fail to initiate expansion programs in timely fashion in the gut. All together, these data point to a model in which Hoxb5b regulates NCCs both in a tissue specific and temporally restricted manner.
]]></description>
<dc:creator>Howard, A. G. A.</dc:creator>
<dc:creator>Nguyen, A. C.</dc:creator>
<dc:creator>Tworig, J.</dc:creator>
<dc:creator>Ravisankar, P.</dc:creator>
<dc:creator>Singleton, E. W.</dc:creator>
<dc:creator>Li, C.</dc:creator>
<dc:creator>Kotzur, G.</dc:creator>
<dc:creator>Waxman, J. S.</dc:creator>
<dc:creator>Uribe, R. A.</dc:creator>
<dc:date>2021-10-29</dc:date>
<dc:identifier>doi:10.1101/2021.10.28.466356</dc:identifier>
<dc:title><![CDATA[Elevated Hoxb5b expands vagal neural crest pool and blocks enteric neuronal development in zebrafish]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.29.466528v1?rss=1">
<title>
<![CDATA[
Decoding grasp and speech signals from the cortical grasp circuit in a tetraplegic human 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.29.466528v1?rss=1</link>
<description><![CDATA[
Tetraplegia from spinal cord injury leaves many patients paralyzed below the neck, leaving them unable to perform most activities of daily living. Brain-machine interfaces (BMIs) could give tetraplegic patients more independence by directly utilizing brain signals to control external devices such as robotic arms or hands. The cortical grasp network has been of particular interest because of its potential to facilitate the restoration of dexterous object manipulation. However, a network that involves such high-level cortical areas may also provide additional information, such as the encoding of speech. Towards understanding the role of different brain areas in the human cortical grasp network, neural activity related to motor intentions for grasping and performing speech was recorded in a tetraplegic patient in the supramarginal gyrus (SMG), the ventral premotor cortex (PMv), and the somatosensory cortex (S1). We found that in high-level brain areas SMG and PMv, grasps were well represented by firing rates of neuronal populations already at visual cue presentation. During motor imagery, grasps could be significantly decoded from all brain areas. At identical neuronal population sizes, SMG and PMv achieved similar highly-significant decoding abilities, demonstrating their potential for grasp BMIs. During speech, SMG encoded both spoken grasps and colors, in contrast to PMv and S1, which were not able to significantly decode speech.These findings suggest that grasp signals can robustly be decoded at a single unit level from the cortical grasping circuit in human. Data from PMv suggests a specialized role in grasping, while SMGs role is broader and extends to speech. Together, these results indicate that brain signals from high-level areas of the human cortex can be exploited for a variety of different BMI applications.
]]></description>
<dc:creator>Wandelt, S. K.</dc:creator>
<dc:creator>Kellis, S.</dc:creator>
<dc:creator>Bjanes, D.</dc:creator>
<dc:creator>Pejsa, K.</dc:creator>
<dc:creator>Lee, B.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2021-11-01</dc:date>
<dc:identifier>doi:10.1101/2021.10.29.466528</dc:identifier>
<dc:title><![CDATA[Decoding grasp and speech signals from the cortical grasp circuit in a tetraplegic human]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.01.466752v1?rss=1">
<title>
<![CDATA[
Bacterial growth in multicellular aggregates leads to the emergence of complex lifecycles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.01.466752v1?rss=1</link>
<description><![CDATA[
In response to environmental stresses such as starvation, many bacteria facultatively aggregate into multicellular structures that can attain new metabolic functions and behaviors. Despite the ubiquity and relevance of this form of collective behavior, we lack an understanding of how the spatiotemporal dynamics of aggregate development emerge from cellular physiology. Here, we show that the coupling between growth and spatial gradient formation leads to the emergence of a complex lifecycle, akin to those known for multicellular bacteria. Under otherwise carbon-limited growth conditions, the marine bacterium Vibrio splendidus 12B01 forms multicellular groups to collectively harvest carbon from the brown-algal polysaccharide alginate. This is achieved during growth on dissolved alginate polymer through formation of spherical, clonal clusters of cells that grow up to 40 {micro}m in radius. Clusters develop striking spatial patterning as they grow due to phenotypic differentiation of sub-populations into a  shell of static cells surrounding a motile  core. Combining in situ measurements of cell physiology with transcriptomics, we show that shell cells express adhesive type IV pili, while motile core cells express carbon storage granules. The emergence of shell and core phenotypes is cued by opposing gradients of carbon and nitrogen that form within cell clusters due to local metabolic activity. Eventually, the shell ruptures, releasing the carbon-storing core, and we show that carbon-storing cells more readily propagate on alginate than non-carbon storing cells. We propose that phenotypic differentiation promotes the resilience of 12B01 groups by enabling clonal groups to grow larger and propagate more effectively. Phenotypic differentiation may be a widespread, but overlooked, strategy among bacteria to enhance resilience in the context of resource limitation.
]]></description>
<dc:creator>Schwartzman, J. A.</dc:creator>
<dc:creator>Ebrahimi, A.</dc:creator>
<dc:creator>Chadwick, G.</dc:creator>
<dc:creator>Sato, Y.</dc:creator>
<dc:creator>Orphan, V.</dc:creator>
<dc:creator>Cordero, O. X.</dc:creator>
<dc:date>2021-11-01</dc:date>
<dc:identifier>doi:10.1101/2021.11.01.466752</dc:identifier>
<dc:title><![CDATA[Bacterial growth in multicellular aggregates leads to the emergence of complex lifecycles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.02.466200v1?rss=1">
<title>
<![CDATA[
Neutralizing antibodies induced in immunized macaques recognize the CD4-binding site on an occluded-open HIV-1 envelope trimer 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.02.466200v1?rss=1</link>
<description><![CDATA[
Broadly-neutralizing antibodies (bNAbs) against HIV-1 Env can protect from infection. We characterize Ab1303 and Ab1573, heterologously-neutralizing CD4-binding site (CD4bs) antibodies, isolated from sequentially-immunized macaques. Ab1303/Ab1573 binding is observed only when Env trimers are not constrained in the closed, prefusion conformation. Fab-Env cryo-EM structures show that both antibodies recognize the CD4bs on Env trimer with an  occluded-open conformation between closed, as targeted by bNAbs, and fully-open, as recognized by CD4. The occluded-open Env trimer conformation includes outwardly-rotated gp120 subunits, but unlike CD4-bound Envs, does not exhibit V1V2 displacement, 4-stranded gp120 bridging sheet, or co-receptor binding site exposure. Inter-protomer distances within trimers measured by double electron-electron resonance spectroscopy suggest an equilibrium between occluded-open and closed Env conformations, consistent with Ab1303/Ab1573 binding stabilizing an existing conformation. Studies of Ab1303/Ab1573 demonstrate that CD4bs neutralizing antibodies that bind open Env trimers can be raised by immunization, thereby informing immunogen design and antibody therapeutic efforts.
]]></description>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Dam, K.-M. A.</dc:creator>
<dc:creator>Bridges, M. D.</dc:creator>
<dc:creator>Hoffmann, M. A. G.</dc:creator>
<dc:creator>DeLaitsch, A. T.</dc:creator>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>Escolano, A.</dc:creator>
<dc:creator>Gautam, R.</dc:creator>
<dc:creator>Martin, M. A.</dc:creator>
<dc:creator>Nussenzweig, M.</dc:creator>
<dc:creator>Hubbell, W.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2021-11-04</dc:date>
<dc:identifier>doi:10.1101/2021.11.02.466200</dc:identifier>
<dc:title><![CDATA[Neutralizing antibodies induced in immunized macaques recognize the CD4-binding site on an occluded-open HIV-1 envelope trimer]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.02.466666v1?rss=1">
<title>
<![CDATA[
Montage electron tomography of vitrified specimens 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.02.466666v1?rss=1</link>
<description><![CDATA[
Cryo-electron tomography provides detailed views of macromolecules in situ. However, imaging a large field of view to provide more cellular context requires reducing magnification during data collection, which in turn restricts the resolution. To circumvent this trade-off between field of view and resolution, we have developed a montage data collection scheme that uniformly distributes the dose throughout the specimen. In this approach, sets of slightly overlapping circular tiles are collected at high magnification and stitched to form a composite projection image at each tilt angle. These montage tilt-series are then reconstructed into massive tomograms with a small pixel size but a large field of view. For proof-of-principle, we applied this method to the thin edge of HeLa cells. Thon rings to better than 15 [A] were observed in the montaged tilt-series, and diverse cellular features were evident in the resulting tomograms. These results indicate that the additional dose required by this technique is not prohibitive to performing structural analysis to intermediate resolution across a large field of view. We anticipate that montage tomography will prove particularly useful for lamellae, increase the likelihood of imaging rare cellular events, and facilitate visual proteomics.
]]></description>
<dc:creator>Peck, A.</dc:creator>
<dc:creator>Carter, S. D.</dc:creator>
<dc:creator>Mai, H.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Burt, A.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2021-11-04</dc:date>
<dc:identifier>doi:10.1101/2021.11.02.466666</dc:identifier>
<dc:title><![CDATA[Montage electron tomography of vitrified specimens]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.07.467589v1?rss=1">
<title>
<![CDATA[
Interneuron Control of C. elegans Developmental Decision-making 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.07.467589v1?rss=1</link>
<description><![CDATA[
Animals integrate external stimuli to shape their physiological responses throughout development. In adverse environments, Caenorhabditis elegans larvae can enter a stress-resistant diapause state with arrested metabolism and reproductive physiology. Amphid sensory neurons feed into both rapid chemotactic and short-term foraging mode decisions, mediated by amphid and premotor interneurons, as well as the long-term diapause decision. We identify amphid interneurons that integrate pheromone cues and propagate this information via a neuropeptidergic pathways to influence larval developmental fate, bypassing the pre-motor system. AIA interneuron-derived FLP-2 neuropeptide signaling promotes reproductive growth and AIA activity is suppressed by pheromone. FLP-2 acts antagonistically to the insulin-like INS-1. FLP-2s growth promoting effects are inhibited by upstream metabotropic glutamatergic signaling and mediated by the broadly-expressed neuropeptide receptor NPR-30. Conversely, the AIB interneurons and their neuropeptide receptor NPR-9/GALR2 promote diapause entry. These neuropeptidergic outputs allow reuse of parts of a sensory system for a decision with a distinct timescale.
]]></description>
<dc:creator>Chai, C. M.</dc:creator>
<dc:creator>Torkashvand, M.</dc:creator>
<dc:creator>Seyedolmohadesin, M.</dc:creator>
<dc:creator>Park, H.</dc:creator>
<dc:creator>Venkatachalam, V.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2021-11-08</dc:date>
<dc:identifier>doi:10.1101/2021.11.07.467589</dc:identifier>
<dc:title><![CDATA[Interneuron Control of C. elegans Developmental Decision-making]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.09.467890v1?rss=1">
<title>
<![CDATA[
FLIP: Benchmark tasks in fitness landscape inference for proteins 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.09.467890v1?rss=1</link>
<description><![CDATA[
Machine learning could enable an unprecedented level of control in protein engineering for therapeutic and industrial applications. Critical to its use in designing proteins with desired properties, machine learning models must capture the protein sequence-function relationship, often termed fitness landscape. Existing bench-marks like CASP or CAFA assess structure and function predictions of proteins, respectively, yet they do not target metrics relevant for protein engineering. In this work, we introduce Fitness Landscape Inference for Proteins (FLIP), a benchmark for function prediction to encourage rapid scoring of representation learning for protein engineering. Our curated tasks, baselines, and metrics probe model generalization in settings relevant for protein engineering, e.g. low-resource and extrapolative. Currently, FLIP encompasses experimental data across adeno-associated virus stability for gene therapy, protein domain B1 stability and immunoglobulin binding, and thermostability from multiple protein families. In order to enable ease of use and future expansion to new tasks, all data are presented in a standard format. FLIP scripts and data are freely accessible at https://benchmark.protein.properties.
]]></description>
<dc:creator>Dallago, C.</dc:creator>
<dc:creator>Mou, J.</dc:creator>
<dc:creator>Johnston, K. E.</dc:creator>
<dc:creator>Wittmann, B.</dc:creator>
<dc:creator>Bhattacharya, N.</dc:creator>
<dc:creator>Goldman, S. L.</dc:creator>
<dc:creator>Madani, A.</dc:creator>
<dc:creator>Yang, K. K.</dc:creator>
<dc:date>2021-11-11</dc:date>
<dc:identifier>doi:10.1101/2021.11.09.467890</dc:identifier>
<dc:title><![CDATA[FLIP: Benchmark tasks in fitness landscape inference for proteins]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.10.468102v1?rss=1">
<title>
<![CDATA[
Real-time Image Denoising of Mixed Poisson-Gaussian Noise in Fluorescence Microscopy Images using ImageJ 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.10.468102v1?rss=1</link>
<description><![CDATA[
AO_SCPLOWBSTRACTC_SCPLOWFluorescence microscopy imaging speed is fundamentally limited by the measurement signal-to-noise ratio (SNR). To improve image SNR for a given image acquisition rate, computational denoising techniques can be used to suppress noise. However, common techniques to estimate a denoised image from a single frame are either computationally expensive or rely on simple noise statistical models. These models assume Poisson or Gaussian noise statistics, which are not appropriate for many fluorescence microscopy applications that contain quantum shot noise and electronic Johnson-Nyquist noise, therefore a mixture of Poisson and Gaussian noise. In this paper, we show convolutional neural networks (CNNs) trained on mixed Poisson and Gaussian noise images to overcome the limitations of existing image denoising methods. The trained CNN is presented as an open-source ImageJ plugin that performs real-time image denoising (within tens of milliseconds) with superior performance (SNR improvement) compared to the conventional fluorescence microscopy denoising methods. The method is validated on external datasets with out-of-distribution noise, contrast, structure, and imaging modalities from the training data and consistently achieves high performance (> 8 dB) denoising in less time than other fluorescence microscopy denoising methods.
]]></description>
<dc:creator>Mannam, V.</dc:creator>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Zhu, Y.</dc:creator>
<dc:creator>Nichols, E.</dc:creator>
<dc:creator>Wang, Q.</dc:creator>
<dc:creator>Sundaresan, V.</dc:creator>
<dc:creator>Zhang, S.</dc:creator>
<dc:creator>Smith, C.</dc:creator>
<dc:creator>Bohn, P. W.</dc:creator>
<dc:creator>Howard, S.</dc:creator>
<dc:date>2021-11-13</dc:date>
<dc:identifier>doi:10.1101/2021.11.10.468102</dc:identifier>
<dc:title><![CDATA[Real-time Image Denoising of Mixed Poisson-Gaussian Noise in Fluorescence Microscopy Images using ImageJ]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.10.468161v1?rss=1">
<title>
<![CDATA[
Resting-state functional connectivity of social brain regions predicts motivated dishonesty 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.10.468161v1?rss=1</link>
<description><![CDATA[
Motivated dishonesty is a typical social behavior varying from person to person. Resting-state fMRI (rsfMRI) is capable of identifying unique patterns from functional connectivity (FC) between brain networks. To identify the relevant neural patterns and build an interpretable model to predict dishonesty, we scanned 8-min rsfMRI before an information-passing task. In the task, we employed monetary rewards to induce dishonesty. We applied both connectome-based predictive modeling (CPM) and region-of-interest (ROI) analysis to examine the association between FC and dishonesty. CPM indicated that the stronger FC between fronto-parietal and default mode networks can predict a higher dishonesty rate. The ROIs were set in the regions involving four cognitive processes (self-reference, cognitive control, reward valuation, and moral regulation). The ROI analyses showed that a stronger FC between these regions and the prefrontal cortex can predict a higher dishonesty rate. Our study offers an integrated model to predict dishonesty with rsfMRI, and the results suggest that the frequent motivated dishonest behavior may require a higher engagement of social brain regions.
]]></description>
<dc:creator>Pang, L.</dc:creator>
<dc:creator>Li, H.</dc:creator>
<dc:creator>Liu, Q.</dc:creator>
<dc:creator>Luo, Y.-j.</dc:creator>
<dc:creator>Mobbs, D.</dc:creator>
<dc:creator>Wu, H.</dc:creator>
<dc:date>2021-11-13</dc:date>
<dc:identifier>doi:10.1101/2021.11.10.468161</dc:identifier>
<dc:title><![CDATA[Resting-state functional connectivity of social brain regions predicts motivated dishonesty]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.12.468428v1?rss=1">
<title>
<![CDATA[
#COVIDisAirborne: AI-Enabled Multiscale Computational Microscopy of Delta SARS-CoV-2 in a Respiratory Aerosol 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.12.468428v1?rss=1</link>
<description><![CDATA[
We seek to completely revise current models of airborne transmission of respiratory viruses by providing never-before-seen atomic-level views of the SARS-CoV-2 virus within a respiratory aerosol. Our work dramatically extends the capabilities of multiscale computational microscopy to address the significant gaps that exist in current experimental methods, which are limited in their ability to interrogate aerosols at the atomic/molecular level and thus ob-scure our understanding of airborne transmission. We demonstrate how our integrated data-driven platform provides a new way of exploring the composition, structure, and dynamics of aerosols and aerosolized viruses, while driving simulation method development along several important axes. We present a series of initial scientific discoveries for the SARS-CoV-2 Delta variant, noting that the full scientific impact of this work has yet to be realized.

ACM Reference FormatAbigail Dommer1{dagger}, Lorenzo Casalino1{dagger}, Fiona Kearns1{dagger}, Mia Rosenfeld1, Nicholas Wauer1, Surl-Hee Ahn1, John Russo,2 Sofia Oliveira3, Clare Morris1, AnthonyBogetti4, AndaTrifan5,6, Alexander Brace5,7, TerraSztain1,8, Austin Clyde5,7, Heng Ma5, Chakra Chennubhotla4, Hyungro Lee9, Matteo Turilli9, Syma Khalid10, Teresa Tamayo-Mendoza11, Matthew Welborn11, Anders Christensen11, Daniel G. A. Smith11, Zhuoran Qiao12, Sai Krishna Sirumalla11, Michael OConnor11, Frederick Manby11, Anima Anandkumar12,13, David Hardy6, James Phillips6, Abraham Stern13, Josh Romero13, David Clark13, Mitchell Dorrell14, Tom Maiden14, Lei Huang15, John McCalpin15, Christo- pherWoods3, Alan Gray13, MattWilliams3, Bryan Barker16, HarindaRajapaksha16, Richard Pitts16, Tom Gibbs13, John Stone6, Daniel Zuckerman2*, Adrian Mulholland3*, Thomas MillerIII11,12*, ShantenuJha9*, Arvind Ramanathan5*, Lillian Chong4*, Rommie Amaro1*. 2021. #COVIDisAirborne: AI-Enabled Multiscale Computational Microscopy ofDeltaSARS-CoV-2 in a Respiratory Aerosol. In Supercomputing  21: International Conference for High Perfor-mance Computing, Networking, Storage, and Analysis. ACM, New York, NY, USA, 14 pages. https://doi.org/finalDOI
]]></description>
<dc:creator>Dommer, A.</dc:creator>
<dc:creator>Casalino, L.</dc:creator>
<dc:creator>Kearns, F.</dc:creator>
<dc:creator>Rosenfeld, M.</dc:creator>
<dc:creator>Wauer, N.</dc:creator>
<dc:creator>Ahn, S.-H.</dc:creator>
<dc:creator>Russo, J.</dc:creator>
<dc:creator>Oliveira, S.</dc:creator>
<dc:creator>Morris, C.</dc:creator>
<dc:creator>Bogetti, A.</dc:creator>
<dc:creator>Trifan, A.</dc:creator>
<dc:creator>Brace, A.</dc:creator>
<dc:creator>Sztain, T.</dc:creator>
<dc:creator>Clyde, A.</dc:creator>
<dc:creator>Ma, H.</dc:creator>
<dc:creator>Chennubhotla, C.</dc:creator>
<dc:creator>Lee, H.</dc:creator>
<dc:creator>Turilli, M.</dc:creator>
<dc:creator>Khalid, S.</dc:creator>
<dc:creator>Tamayo-Mendoza, T.</dc:creator>
<dc:creator>Welborn, M.</dc:creator>
<dc:creator>Christiansen, A.</dc:creator>
<dc:creator>Smith, D. G. A.</dc:creator>
<dc:creator>Qiao, Z.</dc:creator>
<dc:creator>Sirumalla, S. K.</dc:creator>
<dc:creator>O'Connor, M.</dc:creator>
<dc:creator>Manby, F.</dc:creator>
<dc:creator>Anandkumar, A.</dc:creator>
<dc:creator>Hardy, D.</dc:creator>
<dc:creator>Phillips, J.</dc:creator>
<dc:creator>Stern, A.</dc:creator>
<dc:creator>Romero, J.</dc:creator>
<dc:creator>Clark, D.</dc:creator>
<dc:creator>Dorrell, M.</dc:creator>
<dc:creator>Maiden, T.</dc:creator>
<dc:creator>Huang, L.</dc:creator>
<dc:creator>McCalpin, J.</dc:creator>
<dc:creator>Woods, C.</dc:creator>
<dc:creator>Gray, A.</dc:creator>
<dc:creator>Williams, M.</dc:creator>
<dc:creator>Barker, B.</dc:creator>
<dc:creator>Rajapaksha, H.</dc:creator>
<dc:creator>Pitts, R.</dc:creator>
<dc:creator>Gibbs, T.</dc:creator>
<dc:creator>Stone, J.</dc:creator>
<dc:creator>Zuckerman, D.</dc:creator>
<dc:creator>Muholland,</dc:creator>
<dc:date>2021-11-15</dc:date>
<dc:identifier>doi:10.1101/2021.11.12.468428</dc:identifier>
<dc:title><![CDATA[#COVIDisAirborne: AI-Enabled Multiscale Computational Microscopy of Delta SARS-CoV-2 in a Respiratory Aerosol]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.15.468770v1?rss=1">
<title>
<![CDATA[
Comparative genomics on cultivated and uncultivated, freshwater and marine Candidatus Manganitrophaceae species implies their worldwide reach in manganese chemolithoautotrophy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.15.468770v1?rss=1</link>
<description><![CDATA[
Chemolithoautotrophic manganese oxidation has long been theorized, but only recently demonstrated in a bacterial co-culture. The majority member of the co-culture, Candidatus Manganitrophus noduliformans, is a distinct but not yet isolated lineage in the phylum Nitrospirota (Nitrospirae). Here, we established two additional MnCO3-oxidizing cultures using inocula from Santa Barbara (USA) and Boetsap (South Africa). Both cultures were dominated by strains of a new species, designated Candidatus Manganitrophus morganii. The next abundant members differed in the available cultures, suggesting that while Ca. Manganitrophus species have not been isolated in pure culture, they may not require a specific syntrophic relationship with another species. Phylogeny of cultivated Ca. Manganitrophus and related metagenome-assembled genomes revealed a coherent taxonomic family, Candidatus Manganitrophaceae, from both freshwater and marine environments and distributed globally. Comparative genomic analyses support this family being Mn(II)-oxidizing chemolithoautotrophs. Among the 895 shared genes were a subset of those hypothesized for Mn(II) oxidation (Cyc2 and PCC_1) and oxygen reduction (TO_1 and TO_2) that could facilitate Mn(II) lithotrophy. An unusual, plausibly reverse Complex 1 containing 2 additional pumping subunits was also shared by the family, as were genes for the reverse TCA carbon fixation cycle, which could enable Mn(II) autotrophy. All members of the family lacked genes for nitrification found in Nitrospira species. The results suggest that Ca. Manganitrophaceae share a core set of candidate genes for the newly discovered manganese dependent chemolithoautotrophic lifestyle, and likely have a broad, global distribution.

ImportanceManganese (Mn) is an abundant redox-active metal that cycled in many of Earths biomes. While diverse bacteria and archaea have been demonstrated to respire Mn(III/IV), only recently have bacteria been implicated in Mn(II) oxidation dependent growth. Here, two new Mn(II)-oxidizing enrichment cultures originated from two continents and hemispheres were examined. By comparing the community composition of the enrichments and performing phylogenomic analysis on the abundant Nitrospirota therein, new insights are gleaned on cell interactions, taxonomy, and machineries that may underlie Mn(II)-based lithotrophy and autotrophy.
]]></description>
<dc:creator>Yu, H.</dc:creator>
<dc:creator>Chadwick, G. L.</dc:creator>
<dc:creator>Lingappa, U. F.</dc:creator>
<dc:creator>Leadbetter, J. R.</dc:creator>
<dc:date>2021-11-16</dc:date>
<dc:identifier>doi:10.1101/2021.11.15.468770</dc:identifier>
<dc:title><![CDATA[Comparative genomics on cultivated and uncultivated, freshwater and marine Candidatus Manganitrophaceae species implies their worldwide reach in manganese chemolithoautotrophy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.17.469050v1?rss=1">
<title>
<![CDATA[
Guide-directed DNA cleavage by a prokaryotic Argonaute protein induces chromosome recombination in Escherichia coli 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.17.469050v1?rss=1</link>
<description><![CDATA[
Many prokaryotic argonautes (pAgos) mediate DNA interference by using small DNA guides to cleave target DNA. A recent study shows that CbAgo, a pAgo from Clostridium butyricum, induces DNA interference between homologous sequences and generates double-stranded breaks (DSBs) in target DNAs. This mechanism enables the host to defend against invading DNAs such as plasmids and viruses. However, whether such a CbAgo-mediated DNA cleavage is mutagenic remains unexplored. Here we demonstrate that CbAgo, directed by plasmid-encoded guide sequences, can cleave genome target sites and induce chromosome recombination between downstream homologous sequences in Escherichia coli. The recombination rate correlates well with pAgo DNA cleavage activity and the mechanistic study suggests the recombination involves DSBs and RecBCD processing. In RecA-deficient E. coli strain, guide-directed CbAgo cleavage on chromosomes severely impairs cell growth, which can be utilized as counter-selection to assist Lambda-Red recombineering. These findings demonstrate the guide-directed cleavage of pAgo on the host genome is mutagenic and can lead to different outcomes according to the function of the host DNA repair machinery. We anticipate this novel DNA-guided interference to be useful in broader genetic manipulation. Our study also provides an in vivo assay to characterize or engineer pAgo DNA cleavage activity.
]]></description>
<dc:creator>Huang, S.</dc:creator>
<dc:creator>Wang, K.</dc:creator>
<dc:creator>Mayo, S. L.</dc:creator>
<dc:date>2021-11-18</dc:date>
<dc:identifier>doi:10.1101/2021.11.17.469050</dc:identifier>
<dc:title><![CDATA[Guide-directed DNA cleavage by a prokaryotic Argonaute protein induces chromosome recombination in Escherichia coli]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.18.469165v1?rss=1">
<title>
<![CDATA[
Adaptive ratchets and the evolution of molecular complexity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.18.469165v1?rss=1</link>
<description><![CDATA[
Biological systems have evolved to amazingly complex states, yet we do not understand in general how evolution operates to generate increasing genetic and functional complexity. Molecular recognition sites are short genome segments or peptides binding a cognate recognition target of sufficient sequence similarity. Such sites are simple, ubiquitous modules of sequence information, cellular function, and evolution. Here we show that recognition sites, if coupled to a time-dependent target, can rapidly evolve to complex states with larger code length and smaller coding density than sites recognising a static target. The underlying fitness model contains selection for recognition, which depends on the sequence similarity between site and target, and a uniform cost per unit of code length. Site sequences are shown to evolve in a specific adaptive ratchet, which produces selection of different strength for code extensions and compressions. Ratchet evolution increases the adaptive width of evolved sites, accelerating the adaptation to moving targets and facilitating refinement and innovation of recognition functions. We apply these results to the recognition of fast-evolving antigens by the human immune system. Our analysis shows how molecular complexity can evolve as a collateral to selection for function in a dynamic environment.
]]></description>
<dc:creator>Röschinger, T.</dc:creator>
<dc:creator>Moran Tovar, R.</dc:creator>
<dc:creator>Pompei, S.</dc:creator>
<dc:creator>Lässig, M.</dc:creator>
<dc:date>2021-11-20</dc:date>
<dc:identifier>doi:10.1101/2021.11.18.469165</dc:identifier>
<dc:title><![CDATA[Adaptive ratchets and the evolution of molecular complexity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.18.469179v1?rss=1">
<title>
<![CDATA[
evSeq: Cost-Effective Amplicon Sequencing of Every Variant in a Protein Library 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.18.469179v1?rss=1</link>
<description><![CDATA[
Widespread availability of protein sequence-fitness data would revolutionize both our biochemical understanding of proteins and our ability to engineer them. Unfortunately, even though thousands of protein variants are generated and evaluated for fitness during a typical protein engineering campaign, most are never sequenced, leaving a wealth of potential sequence-fitness information untapped. This largely stems from the fact that sequencing is unnecessary for many protein engineering strategies; the added cost and effort of sequencing is thus unjustified. Here, we present every variant sequencing (evSeq), an efficient protocol for sequencing a variable region within every variant gene produced during a protein engineering campaign at a cost of cents per variant. Execution of evSeq is simple, requires no sequencing experience to perform, relies only on resources and services typically available to biology labs, and slots neatly into existing protein engineering workflows. Analysis of evSeq data is likewise made simple by its accompanying software (found at github.com/fhalab/evSeq, documentation at fhalab.github.io/evSeq), which can be run on a personal laptop and was designed to be accessible to users with no computational experience. Low-cost and easy to use, evSeq makes collection of extensive protein variant sequence-fitness data practical.
]]></description>
<dc:creator>Wittmann, B. J.</dc:creator>
<dc:creator>Johnston, K. E.</dc:creator>
<dc:creator>Almhjell, P. J.</dc:creator>
<dc:creator>Arnold, F. H.</dc:creator>
<dc:date>2021-11-19</dc:date>
<dc:identifier>doi:10.1101/2021.11.18.469179</dc:identifier>
<dc:title><![CDATA[evSeq: Cost-Effective Amplicon Sequencing of Every Variant in a Protein Library]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.19.469083v1?rss=1">
<title>
<![CDATA[
Doppler Slicing for Ultrasound Super-Resolution Without Contrast Agents 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.19.469083v1?rss=1</link>
<description><![CDATA[
Much of the information needed for diagnosis and treatment monitoring of diseases like cancer and cardiovascular disease is found at scales below the resolution limit of classic ultrasound imaging. Recently introduced vascular super-localization methods provide more than a ten-fold improvement in spatial resolution by precisely estimating the positions of microbubble contrast agents. However, most vascular ultrasound scans are currently performed without contrast agents due to the associated cost, training, and post-scan monitoring. Here we show that super-resolution ultrasound imaging of dense vascular structures can be achieved using the natural contrast of flowing blood cells. Instead of relying on separable targets, we used Fourier-based decomposition to separate signals arising from the different scales of vascular structures while removing speckle noise using multi-ensemble processing. This approach enabled the use of compressed sensing for super-resolution imaging of the underlying vascular structures, improving resolution by a factor of four. Reconstruction of ultrafast mouse brain scans revealed details that could not be resolved in regular Doppler images, agreeing closely with bubble-based super-localization microscopy of the same fields of view. By combining multi-ensemble Doppler acquisitions with narrowband Fourier decomposition and computational super-resolution imaging, this approach opens new opportunities for affordable and scalable super-resolution ultrasound imaging.
]]></description>
<dc:creator>Bar-Zion, A.</dc:creator>
<dc:creator>Solomon, O.</dc:creator>
<dc:creator>Rabut, C.</dc:creator>
<dc:creator>Maresca, D.</dc:creator>
<dc:creator>Eldar, Y. C.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2021-11-20</dc:date>
<dc:identifier>doi:10.1101/2021.11.19.469083</dc:identifier>
<dc:title><![CDATA[Doppler Slicing for Ultrasound Super-Resolution Without Contrast Agents]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.23.469799v1?rss=1">
<title>
<![CDATA[
Prevalence and correlates of phenazine resistance in culturable bacteria from a dryland wheat field 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.23.469799v1?rss=1</link>
<description><![CDATA[
Phenazines are a class of bacterially-produced redox-active natural antibiotics that have demonstrated potential as a sustainable alternative to traditional pesticides for the biocontrol of fungal crop diseases. However, the prevalence of bacterial resistance to agriculturally-relevant phenazines is poorly understood, limiting both the understanding of how these molecules might shape rhizosphere bacterial communities and the ability to perform risk assessment for off-target effects. Here, we describe profiles of susceptibility to the antifungal agent phenazine-1-carboxylic acid (PCA) across more than 100 bacterial strains isolated from a wheat field where PCA producers are indigenous and abundant. We find that Gram-positive bacteria are typically more sensitive to PCA than Gram-negative bacteria, but that there is also significant variability in susceptibility both within and across phyla. Phenazine-resistant strains are more likely to be isolated from the wheat rhizosphere, where PCA producers are also more abundant, compared to bulk soil. Furthermore, PCA toxicity is pH-dependent for most susceptible strains and broadly correlates with PCA reduction rates, suggesting that uptake and redox-cycling are important determinants of phenazine toxicity. Our results shed light on which classes of bacteria are most likely to be susceptible to phenazine toxicity in acidic or neutral soils. In addition, the taxonomic and phenotypic diversity of our strain collection represents a valuable resource for future studies on the role of natural antibiotics in shaping wheat rhizosphere communities.

ImportanceMicrobial communities contribute to crop health in important ways. For example, phenazine metabolites are a class of redox-active molecules made by diverse soil bacteria that underpin the biocontrol of wheat and other crops. Their physiological functions are nuanced: in some contexts they are toxic, in others, beneficial. While much is known about phenazine production and the effect of phenazines on producing strains, our ability to predict how phenazines might shape the composition of environmental microbial communities is poorly constrained; that phenazine prevalence in the rhizosphere is predicted to increase in arid soils as the climate changes provides an impetus for further study. As a step towards gaining a predictive understanding of phenazine-linked microbial ecology, we document the effects of phenazines on diverse bacteria that were co-isolated from a wheat rhizosphere and identify conditions and phenotypes that correlate with how a strain will respond to phenazines.
]]></description>
<dc:creator>Perry, E.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2021-11-24</dc:date>
<dc:identifier>doi:10.1101/2021.11.23.469799</dc:identifier>
<dc:title><![CDATA[Prevalence and correlates of phenazine resistance in culturable bacteria from a dryland wheat field]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.24.469943v1?rss=1">
<title>
<![CDATA[
Spectral organ fingerprints for intraoperative tissue classification with hyperspectral imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.24.469943v1?rss=1</link>
<description><![CDATA[
Visual discrimination of tissue during surgery can be challenging since different tissues appear similar to the human eye. Hyperspectral imaging (HSI) removes this limitation by associating each pixel with high-dimensional spectral information. While previous work has shown its general potential to discriminate tissue, clinical translation has been limited due to the methods current lack of robustness and generalizability. Specifically, it had been unknown whether variability in spectral reflectance is primarily explained by tissue type rather than the recorded individual or specific acquisition conditions. The contribution of this work is threefold: (1) Based on an annotated medical HSI data set (9,059 images from 46 pigs), we present a tissue atlas featuring spectral fingerprints of 20 different porcine organs and tissue types. (2) Using the principle of mixed model analysis, we show that the greatest source of variability related to HSI images is the organ under observation. (3) We show that HSI-based fully-automatic tissue differentiation of 20 organ classes with deep neural networks is possible with high accuracy (> 95 %). We conclude from our study that automatic tissue discrimination based on HSI data is feasible and could thus aid in intraoperative decision making and pave the way for context-aware computer-assisted surgery systems and autonomous robotics.
]]></description>
<dc:creator>Studier-Fischer, A.</dc:creator>
<dc:creator>Seidlitz, S.</dc:creator>
<dc:creator>Sellner, J.</dc:creator>
<dc:creator>Wiesenfarth, M.</dc:creator>
<dc:creator>Ayala, L.</dc:creator>
<dc:creator>Oezdemir, B.</dc:creator>
<dc:creator>Odenthal, J.</dc:creator>
<dc:creator>Knoedler, S.</dc:creator>
<dc:creator>Kowalewski, K.-F.</dc:creator>
<dc:creator>Haney, C. M.</dc:creator>
<dc:creator>Camplisson, I.</dc:creator>
<dc:creator>Dietrich, M.</dc:creator>
<dc:creator>Schmidt, K.</dc:creator>
<dc:creator>Salg, G.</dc:creator>
<dc:creator>Kenngott, H. G.</dc:creator>
<dc:creator>Adler, T. J.</dc:creator>
<dc:creator>Schreck, N.</dc:creator>
<dc:creator>Kopp-Schneider, A.</dc:creator>
<dc:creator>Maier-Hein, K.</dc:creator>
<dc:creator>Maier-Hein, L.</dc:creator>
<dc:creator>Mueller-Stich, B. P.</dc:creator>
<dc:creator>Nickel, F.</dc:creator>
<dc:date>2021-11-25</dc:date>
<dc:identifier>doi:10.1101/2021.11.24.469943</dc:identifier>
<dc:title><![CDATA[Spectral organ fingerprints for intraoperative tissue classification with hyperspectral imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.12.01.470848v1?rss=1">
<title>
<![CDATA[
Redox-active secondary metabolites act as interspecies modulators of antibiotic resilience 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.12.01.470848v1?rss=1</link>
<description><![CDATA[
Bacterial opportunistic pathogens make a wide range of secondary metabolites both in the natural environment and when causing infections, yet how these molecules mediate microbial interactions and their consequences for antibiotic treatment are still poorly understood. Here, we explore the role of two redox-active secondary metabolites, pyocyanin and toxoflavin, as interspecies modulators of antibiotic resilience. We find that these molecules dramatically change susceptibility levels of diverse bacteria to clinical antibiotics. Pyocyanin is made by Pseudomonas aeruginosa, while toxoflavin is made by Burkholderia gladioli, organisms that infect cystic fibrosis and other immunocompromised patients. Both molecules alter the susceptibility profile of pathogenic species within the "Burkholderia cepacia complex" to different antibiotics, either antagonizing or potentiating their effects, depending on the drugs class. Defense responses regulated by the redox-sensitive transcription factor SoxR potentiate the antagonistic effects these metabolites have against fluoroquinolones, and the presence of genes encoding SoxR and the efflux systems it regulates can be used to predict how these metabolites will affect antibiotic susceptibility of different bacteria. Finally, we demonstrate that inclusion of secondary metabolites in standard protocols used to assess antibiotic resistance can dramatically alter the results, motivating the development of new tests for more accurate clinical assessment.
]]></description>
<dc:creator>Meirelles, L. A.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2021-12-02</dc:date>
<dc:identifier>doi:10.1101/2021.12.01.470848</dc:identifier>
<dc:title><![CDATA[Redox-active secondary metabolites act as interspecies modulators of antibiotic resilience]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-12-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.12.08.471788v1?rss=1">
<title>
<![CDATA[
Efficient pre-processing of Single-cell ATAC-seq data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.12.08.471788v1?rss=1</link>
<description><![CDATA[
Single-cell and single-nucleus genomics assays are becoming increasingly complex, with multiple measurements of distinct modalities performed concurrently resulting in "multimodal" readouts. While multimodal single-cell and single-nucleus genomics offers the potential to better understand how distinct cellular processes are coordinated, there can be technical and cost tradeoffs associated with increasing the number of measurement modes. To assess some of the tradeoffs inherent in multimodal assays, we have developed snATAK for preprocessing sequencing-based high-throughput assays that measure single-nucleus chromatin accessibility. Coupled with kallisto bustools for single-nucleus RNA-seq preprocessing, the snATAK workflow can be used for uniform preprocessing of 10x Genomics Multiome and single-nucleus ATAC-seq, SHARE-seq, ISSAAC-seq, spatial ATAC-seq and other chromatin-related assays. Using snATAK, we are able to perform cross-platform comparisons and quantify some of the tradeoffs between Multiome and unregistered single-nucleus RNA-seq/ATAC-seq experiments. We also show that snATAK can be used to assess allele concordance between paired RNAseq and ATACseq. snATAK is available at https://github.com/pachterlab/snATAK/.
]]></description>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2021-12-10</dc:date>
<dc:identifier>doi:10.1101/2021.12.08.471788</dc:identifier>
<dc:title><![CDATA[Efficient pre-processing of Single-cell ATAC-seq data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-12-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.12.09.472001v1?rss=1">
<title>
<![CDATA[
The double-edged role of nitric oxide drives predictable microbial community organization according to the microenvironment 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.12.09.472001v1?rss=1</link>
<description><![CDATA[
Microbial assemblages are omnipresent in the biosphere, forming communities on the surfaces of roots, rocks, and within living tissues. These communities can exhibit strikingly beautiful compositional structures, with certain members reproducibly occupying particular spatiotemporal microniches. Despite this reproducibility, we lack the ability to explain these spatial patterns. We hypothesize that certain spatial patterns in microbial communities may be explained by the exchange of redox-active metabolites whose biological function is sensitive to microenvironmental gradients. To test this, we developed a simple community consisting of synthetic Pseudomonas aeruginosa strains with a partitioned denitrification pathway: a strict consumer and strict producer of nitric oxide (NO), a key pathway intermediate. Because NO can be both toxic or beneficial depending on the amount of oxygen present, this system provided an opportunity to investigate whether dynamic oxygen gradients can tune metabolic cross-feeding and fitness outcomes in a predictable fashion. Using a combination of genetic analysis, controlled growth environments and imaging, we show that oxygen availability dictates whether NO cross-feeding is deleterious or mutually beneficial, and that this organizing principal maps to the microscale. More generally, this work underscores the importance of considering the contrasting and microenvironmentally tuned roles redox-active metabolites can play in shaping microbial communities.
]]></description>
<dc:creator>Wilbert, S. A.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2021-12-09</dc:date>
<dc:identifier>doi:10.1101/2021.12.09.472001</dc:identifier>
<dc:title><![CDATA[The double-edged role of nitric oxide drives predictable microbial community organization according to the microenvironment]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-12-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.12.10.472165v1?rss=1">
<title>
<![CDATA[
Coral larvae suppress the heat stress response during the onset of symbiosis thereby decreasing their odds of survival 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.12.10.472165v1?rss=1</link>
<description><![CDATA[
The endosymbiosis between most corals and their photosynthetic dinoflagellate partners begins early in the host life history, when corals are larvae or juvenile polyps. The capacity of coral larvae to buffer climate-induced stress while in the process of symbiont acquisition could come with physiological trade-offs that alter larval behavior, development, settlement and survivorship. Here we examined the joint effects of thermal stress and symbiosis onset on colonization dynamics, survival, metamorphosis and host gene expression of Acropora digitifera larvae. We found that thermal stress decreased symbiont colonization of hosts by 50% and symbiont density by 98.5% over two weeks. Temperature and colonization also influenced larval survival and metamorphosis in an additive manner, where colonized larvae fared worse or prematurely metamorphosed more often than non-colonized larvae under thermal stress. Transcriptomic responses to colonization and thermal stress treatments were largely independent, while the interaction of these treatments revealed contrasting expression profiles of genes that function in the stress response, immunity, inflammation and cell cycle regulation. The combined treatment either canceled or lowered the magnitude of expression of heat-stress responsive genes in the presence of symbionts, revealing a physiological cost to acquiring symbionts at the larval stage with elevated temperatures. In addition, host immune suppression, a hallmark of symbiosis onset under ambient temperature, turned to immune activation under heat stress. Thus, by integrating the physical environment and biotic pressures that mediate pre-settlement event in corals, our results suggest that colonization may hinder larval survival and recruitment creating isolated, genetically similar populations under projected climate scenarios.
]]></description>
<dc:creator>Kitchen, S. A.</dc:creator>
<dc:creator>Jiang, D.</dc:creator>
<dc:creator>Harii, S.</dc:creator>
<dc:creator>Satoh, N.</dc:creator>
<dc:creator>Weis, V. M.</dc:creator>
<dc:creator>Shinzato, C.</dc:creator>
<dc:date>2021-12-12</dc:date>
<dc:identifier>doi:10.1101/2021.12.10.472165</dc:identifier>
<dc:title><![CDATA[Coral larvae suppress the heat stress response during the onset of symbiosis thereby decreasing their odds of survival]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-12-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.12.13.472443v1?rss=1">
<title>
<![CDATA[
Glutathione binding to the plant At Atm3 transporter and implications for the conformational coupling of ABC transporters 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.12.13.472443v1?rss=1</link>
<description><![CDATA[
The ATP Binding Cassette (ABC) transporter of mitochondria (Atm) from Arabidopsis thaliana (AtAtm3) has been implicated in the maturation of cytosolic iron-sulfur proteins and heavy metal detoxification, plausibly by exporting glutathione derivatives. Using single-particle cryo-electron microscopy, we have determined structures of AtAtm3 in multiple conformational states. These structures not only provide a structural framework for defining the alternating access transport cycle, but also highlight an unappreciated feature of the glutathione binding site, namely the paucity of cysteine residues that could potentially form inhibitory mixed disulfides with glutathione. Despite extensive efforts, we were unable to prepare the ternary complex of AtAtm3 with bound GSSG and MgATP. A survey of structurally characterized type IV ABC transporters that includes AtAtm3 establishes that while nucleotides are found associated with all conformational states, they are effectively required to stabilize occluded and outward-facing conformations. In contrast, transport substrates have only been observed associated with inward-facing conformations. The absence of structures containing both nucleotide and transport substrate suggests that this ternary complex exists only transiently during the transport cycle.
]]></description>
<dc:creator>Fan, C.</dc:creator>
<dc:creator>Rees, D. C.</dc:creator>
<dc:date>2021-12-14</dc:date>
<dc:identifier>doi:10.1101/2021.12.13.472443</dc:identifier>
<dc:title><![CDATA[Glutathione binding to the plant At Atm3 transporter and implications for the conformational coupling of ABC transporters]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-12-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.12.22.473893v1?rss=1">
<title>
<![CDATA[
Coupled protein quality control during nonsense mediated mRNA decay 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.12.22.473893v1?rss=1</link>
<description><![CDATA[
Translation of mRNAs containing premature termination codons (PTCs) can result in truncated protein products with deleterious effects. Nonsense-mediated decay (NMD) is a surveillance path-way responsible for detecting and degrading PTC containing transcripts. While the molecular mechanisms governing mRNA degradation have been extensively studied, the fate of the nascent protein product remains largely uncharacterized. Here, we use a fluorescent reporter system in mammalian cells to reveal a selective degradation pathway specifically targeting the protein product of an NMD mRNA. We show that this process is post-translational, and dependent on an intact ubiquitin proteasome system. To systematically uncover factors involved in NMD-linked protein quality control, we conducted genome-wide flow cytometry-based screens. Our screens recovered known NMD factors, and suggested a lack of dependence on the canonical ribosome-quality control (RQC) pathway. Finally, one of the strongest hits in our screens was the E3 ubiquitin ligase CNOT4, a member of the CCR4-NOT complex, which is involved in initiating mRNA degradation. We show that CNOT4 is involved in NMD coupled protein degradation, and its role depends on a functional RING ubiquitin ligase domain. Our results demonstrate the existence of a targeted pathway for nascent protein degradation from PTC containing mRNAs, and provide a framework for identifying and characterizing factors involved in this process.
]]></description>
<dc:creator>Inglis, A. J.</dc:creator>
<dc:creator>Guna, A.</dc:creator>
<dc:creator>Merchan, A. G.</dc:creator>
<dc:creator>Pal, A.</dc:creator>
<dc:creator>Esantsi, T. K.</dc:creator>
<dc:creator>Keys, H. R.</dc:creator>
<dc:creator>Frenkel, E. M.</dc:creator>
<dc:creator>Oania, R.</dc:creator>
<dc:creator>Weissman, J. S.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:date>2021-12-23</dc:date>
<dc:identifier>doi:10.1101/2021.12.22.473893</dc:identifier>
<dc:title><![CDATA[Coupled protein quality control during nonsense mediated mRNA decay]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-12-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.12.23.473106v1?rss=1">
<title>
<![CDATA[
Polyphosphate affects cytoplasmic and chromosomal dynamics in nitrogen-starved Pseudomonas aeruginosa 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.12.23.473106v1?rss=1</link>
<description><![CDATA[
Polyphosphate (polyP) synthesis is a ubiquitous stress and starvation response in bacteria. In diverse species, mutants unable to make polyP have a wide variety of physiological defects, but the mechanisms by which this simple polyanion exerts its effects remain unclear. One possibility is that polyPs many functions stem from global effects on the biophysical properties of the cell. We characterize the effect of polyphosphate on cytoplasmic mobility under nitrogen-starvation conditions in the opportunistic pathogen Pseudomonas aeruginosa. Using fluorescence microscopy and particle tracking, we characterize the motion of chromosomal loci and free tracer particles in the cytoplasm. In the absence of polyP and upon starvation, we observe an increase in mobility both for chromosomal loci and for tracer particles. Tracer particles reveal that polyP also modulates the partitioning between a  more mobile and a  less mobile population: small particles in cells unable to make polyP are more likely to be  mobile and explore more of the cytoplasm, particularly during starvation. We speculate that this larger freedom of motion may be a consequence of nucleoid decompaction, which we also observe in starved cells deficient in polyP. Our observations suggest that polyP limits cytoplasmic mobility and accessibility during nitrogen starvation, which may help to explain the pleiotropic phenotypes observed in the absence of polyP.
]]></description>
<dc:creator>Magkiriadou, S.</dc:creator>
<dc:creator>Habel, A.</dc:creator>
<dc:creator>Stepp, W. L.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:creator>Manley, S.</dc:creator>
<dc:creator>Racki, L. R.</dc:creator>
<dc:date>2021-12-23</dc:date>
<dc:identifier>doi:10.1101/2021.12.23.473106</dc:identifier>
<dc:title><![CDATA[Polyphosphate affects cytoplasmic and chromosomal dynamics in nitrogen-starved Pseudomonas aeruginosa]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-12-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.12.29.474408v1?rss=1">
<title>
<![CDATA[
Multi-Wavelength Analytical Ultracentrifugation of Biopolymer Mixtures and Interactions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.12.29.474408v1?rss=1</link>
<description><![CDATA[
Multi-wavelength analytical ultracentrifugation (MW-AUC) is a recent development made possible by new analytical ultracentrifuge optical systems. MW-AUC is suitable for a wide range of applications and biopolymer systems and is poised to become an essential tool to characterize macromolecular interactions. It adds an orthogonal spectral dimension to the traditional hydrodynamic characterization by exploiting unique chromophores in analyte mixtures that may or may not interact. Here we illustrate the utility of MW-AUC for representative classes of challenging biopolymer systems, including interactions between mixtures of different sized proteins with small molecules, mixtures of loaded and empty viral AAV capsids contaminated with free DNA, and mixtures of different proteins, where some have identical hydrodynamic properties, all of which are difficult to resolve with traditional AUC methods. We explain the improvement in resolution and information content obtained by this technique compared to traditional single- or dual-wavelength approaches. We discuss experimental design considerations and limitations of the method, and address the advantages and disadvantages of the two MW optical systems available today, and the differences in data analysis strategies between the two systems.
]]></description>
<dc:creator>Henrickson, A.</dc:creator>
<dc:creator>Gorbet, G. E.</dc:creator>
<dc:creator>Savelyev, A.</dc:creator>
<dc:creator>Kim, M.</dc:creator>
<dc:creator>Schultz, S. K.</dc:creator>
<dc:creator>Ding, X.</dc:creator>
<dc:creator>Hargreaves, J.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:creator>Kothe, U.</dc:creator>
<dc:creator>Demeler, B.</dc:creator>
<dc:date>2021-12-30</dc:date>
<dc:identifier>doi:10.1101/2021.12.29.474408</dc:identifier>
<dc:title><![CDATA[Multi-Wavelength Analytical Ultracentrifugation of Biopolymer Mixtures and Interactions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-12-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.01.08.475342v1?rss=1">
<title>
<![CDATA[
Intravenous gene transfer throughout the brain of infant Old World primates using AAV 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.01.08.475342v1?rss=1</link>
<description><![CDATA[
Adeno-associated viruses (AAVs) can enable robust and safe gene delivery to the mammalian central nervous system (CNS). While the scientific community has developed numerous neurotropic AAV variants for systemic gene-transfer to the rodent brain, there are few AAVs that efficiently access the CNS of higher order primates. We describe here AAV.CAP-Mac, an engineered AAV variant that enables systemic, brain-wide gene delivery in infants of two Old World primate species--the rhesus macaque (Macaca mulatta) and the green monkey (Chlorocebus sabaeus). We identified CAP-Mac using a multi-species selection strategy, initially screening our library in the adult common marmoset (Callithrix jacchus) and narrowing our pool of test-variants for another round of selection in infant macaques. In individual characterization, CAP-Mac robustly transduces human neurons in vitro and Old World primate neurons in vivo, where it targets all lobes of cortex, the cerebellum, and multiple subcortical regions of disease relevance. We use CAP-Mac for Brainbow-like multicolor labeling of macaque neurons throughout the brain, enabling morphological reconstruction of both medium spiny neurons and cortical pyramidal cells. Because of its broad distribution throughout the brain and high neuronal efficiency in infant Old World primates compared to AAV9, CAP-Mac shows promise for researchers and clinicians alike to unlock novel, noninvasive access to the brain for efficient gene transfer.
]]></description>
<dc:creator>Chuapoco, M. R.</dc:creator>
<dc:creator>Flytzanis, N.</dc:creator>
<dc:creator>Goeden, N.</dc:creator>
<dc:creator>Octeau, J. C.</dc:creator>
<dc:creator>Roxas, K. M.</dc:creator>
<dc:creator>Chan, K. Y.</dc:creator>
<dc:creator>Scherrer, J.</dc:creator>
<dc:creator>Winchester, J.</dc:creator>
<dc:creator>Blackburn, R. J.</dc:creator>
<dc:creator>Campos, L. J.</dc:creator>
<dc:creator>Arokiaraj, C. M.</dc:creator>
<dc:creator>Miles, T. F.</dc:creator>
<dc:creator>Jang, M. J.</dc:creator>
<dc:creator>Vendemiatti, J.</dc:creator>
<dc:creator>Deverman, B. E.</dc:creator>
<dc:creator>Pickel, J.</dc:creator>
<dc:creator>Fox, A. S.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2022-01-09</dc:date>
<dc:identifier>doi:10.1101/2022.01.08.475342</dc:identifier>
<dc:title><![CDATA[Intravenous gene transfer throughout the brain of infant Old World primates using AAV]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-01-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.01.19.476997v1?rss=1">
<title>
<![CDATA[
Overestimated Polygenic Prediction due to Overlapping Subjects in Genetic Datasets 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.01.19.476997v1?rss=1</link>
<description><![CDATA[
Recently, polygenic risk score (PRS) has gained significant attention in studies involving complex genetic diseases and traits. PRS is often derived from summary statistics, from which the independence between discovery and replication sets cannot be monitored. Prior studies, in which the independence is strictly observed, report a relatively low gain from PRS in predictive models of binary traits. We hypothesize that the independence assumption may be compromised when using the summary statistics, and suspect an overestimation bias in the predictive accuracy. To demonstrate the overestimation bias in the replication dataset, prediction performances of PRS models are compared when overlapping subjects are either present or removed. We consider the task of Alzheimers disease (AD) prediction across genetics datasets, including the International Genomics of Alzheimers Project (IGAP), AD Sequencing Project (ADSP), and Accelerating Medicine Partnership - Alzheimers Disease (AMP-AD). PRS is computed from either sequencing studies for ADSP and AMP-AD (denoted as rPRS) or the summary statistics for IGAP (sPRS). Two variables with the high heritability in UK Biobank, hypertension, and height, are used to derive an exemplary scale effect of PRS. Based on the scale effect, the expected performance of sPRS is computed for AD prediction. Using ADSP as a discovery set for rPRS on AMP-AD, {Delta}AUC and {Delta}R2 (performance gains in AUC and R2 by PRS) record 0.069 and 0.11, respectively. Both drop to 0.0017 and 0.0041 once overlapping subjects are removed from AMP-AD. sPRS is derived from IGAP, which records {Delta}AUC and {Delta}R2 of 0.051{+/-}0.013 and 0.063{+/-}0.015 for ADSP and 0.060 and 0.086 for AMP-AD, respectively. On UK Biobank, rPRS performances for hypertension assuming a similar size of discovery and replication sets are 0.0036{+/-}0.0027 ({Delta}AUC) and 0.0032{+/-}0.0028 ({Delta}R2). For height, {Delta}R2 is 0.029{+/-}0.0037. Considering the high heritability of hypertension and height of UK Biobank, we conclude that sPRS results from AD databases are inflated. The higher performances relative to the size of the discovery set were observed in PRS studies of several diseases. PRS performances for binary traits, such as AD and hypertension, turned out unexpectedly low. This may, along with the difference in linkage disequilibrium, explain the high variability of PRS performances in cross-nation or cross-ethnicity applications, i.e., when there are no overlapping subjects. Hence, for sPRS, potential duplications should be carefully considered within the same ethnic group.
]]></description>
<dc:creator>Park, D. K.</dc:creator>
<dc:creator>Chen, M.</dc:creator>
<dc:creator>Kim, S.</dc:creator>
<dc:creator>Joo, Y. Y.</dc:creator>
<dc:creator>Loving, R.</dc:creator>
<dc:creator>Kim, H.-S.</dc:creator>
<dc:creator>Cha, J.</dc:creator>
<dc:creator>Yoo, S.</dc:creator>
<dc:creator>Kim, J. H.</dc:creator>
<dc:date>2022-01-22</dc:date>
<dc:identifier>doi:10.1101/2022.01.19.476997</dc:identifier>
<dc:title><![CDATA[Overestimated Polygenic Prediction due to Overlapping Subjects in Genetic Datasets]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-01-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.01.24.477460v1?rss=1">
<title>
<![CDATA[
Smart sealants for prevention and monitoring of gastrointestinal anastomotic leaks using portable smartphone-controlled ultrasound transducers 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.01.24.477460v1?rss=1</link>
<description><![CDATA[
Millions of patients every year undergo gastrointestinal surgery. While often lifesaving, sutured and stapled reconnections leak in around 10% of the cases. Penetration of digestive fluids into the peritoneal cavity may lead to dreadful complications, including sepsis and premature death. Modern suture supports and tissue adhesives only insufficiently address the issue. Due to the scarcity of alternatives, surgeons rely on monitoring surrogate markers and clinical symptoms, which oftentimes lack sensitivity and specificity, hence only offering late-stage detection of already fully developed leaks.

Here, a first-of-its-kind, modular, intelligent suture support patch capable of sealing and monitoring leaks under harsh gastrointestinal conditions is presented. The smart adhesive layered hydrogel patch provides, in addition to unprecedented tissue sealing under most demanding conditions, unique leak-detection capabilities based on pH and/or enzyme-responsive sensing elements, which can be read out by non-invasive point-of-need ultrasound imaging. Reliable detection of the breaching of sutures in as little as 3 hours in intestinal leak and 15 minutes in gastric leak conditions, and before an actual leak develops, is demonstrated. This technology paves the way for next-generation suture support materials that offer disambiguation in cases of anastomotic leaks based on point-of-need monitoring, without reliance on complex electronics or bulky (bio)electronic implantables.

SummaryElectronic-free smart surgical hydrogel sealants leveraging tissue-penetrating polymer networks and trigger-responsive echogenic entities to enable point-of-need monitoring and early anastomotic leak detection using a hand-held ultrasound transducer and a smartphone.
]]></description>
<dc:creator>Anthis, A. H. C.</dc:creator>
<dc:creator>Abundo, M. P.</dc:creator>
<dc:creator>Neuer, A. L.</dc:creator>
<dc:creator>Tsolaki, E.</dc:creator>
<dc:creator>Rosendorf, J.</dc:creator>
<dc:creator>Rduch, T.</dc:creator>
<dc:creator>Starsich, F.</dc:creator>
<dc:creator>Liska, V.</dc:creator>
<dc:creator>Schlegel, A. A.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Herrmann, I. K.</dc:creator>
<dc:date>2022-01-27</dc:date>
<dc:identifier>doi:10.1101/2022.01.24.477460</dc:identifier>
<dc:title><![CDATA[Smart sealants for prevention and monitoring of gastrointestinal anastomotic leaks using portable smartphone-controlled ultrasound transducers]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-01-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.01.24.477598v1?rss=1">
<title>
<![CDATA[
Rubisco forms a lattice inside alpha-carboxysomes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.01.24.477598v1?rss=1</link>
<description><![CDATA[
Bacteria employ microcompartments to sequester enzymatic processes, either for purposes of protecting cellular contents from reactive intermediates or as a way of increasing reaction efficiency. In these structures, a cargo of enzymes and accessory proteins is encased within a semi-permeable protein shell that permits passage of substrates and products but restricts movement of intermediates. In addition to their importance as a component of many bacterial species metabolisms, microcompartments have recently become a target of protein engineering. The shells can be reassembled from purified proteins, and the full operons can be functionally expressed outside their native prokaryotes and can remain functional following purification. Despite the importance of microcompartments in prokaryotic biology and bioengineering, structural heterogeneity has prevented a complete understanding of their architecture, ultrastructure, and spatial organization. Here, we employ cryo electron tomography to image -carboxysomes, a pseudo-icosahedral microcompartment responsible for carbon fixation. We have solved a high-resolution subtomogram average of the Rubisco cargo in situ, and determined a novel arrangement of the enzyme. We find that the H. neapolitanus Rubisco polymerizes in vivo, mediated by the small Rubisco subunit. These fibrils can further pack to form a lattice with six-fold pseudo-symmetry. This arrangement preserves freedom of motion and accessibility around the Rubisco active site and the binding sites for two other carboxysome proteins, CsoSCA (a carbonic anhydrase) and the disordered CsoS2, even at Rubisco concentrations exceeding 800 M. This characterization of Rubisco cargo inside the -carboxysome provides new insight into the balance between order and disorder in microcompartment organization.
]]></description>
<dc:creator>Metskas, L. A.</dc:creator>
<dc:creator>Ortega, D. R.</dc:creator>
<dc:creator>Oltrogge, L. M.</dc:creator>
<dc:creator>Blikstad, C.</dc:creator>
<dc:creator>Laughlin, T.</dc:creator>
<dc:creator>Savage, D.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2022-01-25</dc:date>
<dc:identifier>doi:10.1101/2022.01.24.477598</dc:identifier>
<dc:title><![CDATA[Rubisco forms a lattice inside alpha-carboxysomes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-01-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.01.31.478342v1?rss=1">
<title>
<![CDATA[
Bimodally oriented cellulose fibers and reticulated homogalacturonan networks - A direct visualization of Allium cepa primary cell walls 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.01.31.478342v1?rss=1</link>
<description><![CDATA[
One hallmark of plant cells is their pecto-cellulosic cell walls. They protect cells against the environment and high turgor and mediate morphogenesis through the dynamics of their mechanical and chemical properties. The walls are a complex polysaccharidic structure. Although their biochemical composition is well known, how the different components organize in the volume of the cell wall and interact with each other is not well understood and yet is key to the walls mechanical properties. To investigate the ultrastructure of the plant cell wall, we imaged the walls of onion (Allium cepa) bulbs in a near-native state via cryo-Focused Ion Beam milling (cryo-FIB-milling) and cryo-Electron Tomography (cryo-ET). This allowed the high-resolution visualization of cellulose fibers in situ (in muro). We reveal the coexistence of dense fiber fields bathed in a reticulated matrix we termed "meshing," which is more abundant at the inner surface of the cell wall. The fibers adopted a regular bimodal angular distribution at all depths in the cell wall and bundled according to their orientation, creating layers within the cell wall. Concomitantly, employing homogalacturonan (HG)-specific enzymatic digestion, we observed changes in the meshing, suggesting that it is at least in part composed of HG pectins. We propose the following model for the construction of the abaxial epidermal primary cell wall: The cell deposits successive layers of cellulose fibers at -45{degrees} and +45{degrees} relative to the cells long axis and secretes the surrounding HG-rich meshing proximal to the plasma membrane, which then migrates to more distal regions of the cell wall.
]]></description>
<dc:creator>NICOLAS, W. J.</dc:creator>
<dc:creator>Faessler, F.</dc:creator>
<dc:creator>Schur, F. K.</dc:creator>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2022-02-01</dc:date>
<dc:identifier>doi:10.1101/2022.01.31.478342</dc:identifier>
<dc:title><![CDATA[Bimodally oriented cellulose fibers and reticulated homogalacturonan networks - A direct visualization of Allium cepa primary cell walls]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-02-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.02.07.479455v1?rss=1">
<title>
<![CDATA[
Machine learning algorithm to characterize antimicrobial resistance associated with the International Space Station surface microbiome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.02.07.479455v1?rss=1</link>
<description><![CDATA[
BackgroundAntimicrobial Resistance (AMR) has a detrimental impact on human health on Earth and it is equally concerning in other environments such as space due to microgravity, radiation and confinement, especially for long-distance space travel. The International Space Station (ISS) is ideal for investigating microbial diversity and virulence. The shotgun metagenomics data of the ISS generated during the Microbial Tracking - 1 (MT-1) project and resulting metagenome-assembled genomes (MAGs) across three flights in eight different locations during 12 months were used in this study. The objective of this study was to identify the AMR genes associated with whole genomes of 227 cultivable strains, 21 shotgun metagenome sequences, and 24 MAGs retrieved from the ISS environmental samples that were treated with propidium monoazide (PMA; viable microbes).

ResultsWe have analyzed the data using a deep learning model, allowing us to go beyond traditional cut-offs based only on high DNA sequence similarity and extending the catalog of AMR genes. Our results in PMA treated samples revealed AMR dominance in the last flight for Kalamiella piersonii, a bacteria related to urinary tract infection in humans. The analysis of 227 pure strains isolated from the MT-1 project revealed hundreds of antibiotic resistance genes from many isolates, including two top-ranking species that corresponded to strains of Enterobacter bugandensis and Bacillus cereus. Computational predictions were experimentally validated by antibiotic resistance profiles in these two species, showing a high degree of concordance. Specifically, disc assay data confirmed the high resistance of these two pathogens to various beta-lactam antibiotics.

ConclusionOverall, our computational predictions and validation analyses demonstrate the advantages of machine learning to uncover concealed AMR determinants in metagenomics datasets, expanding the understanding of the ISS environmental microbiomes and their pathogenic potential in humans.
]]></description>
<dc:creator>Madrigal, P.</dc:creator>
<dc:creator>Singh, N. K.</dc:creator>
<dc:creator>Wood, J. M.</dc:creator>
<dc:creator>Gaudioso, E.</dc:creator>
<dc:creator>Hernandez-del-Olmo, F.</dc:creator>
<dc:creator>Mason, C. E.</dc:creator>
<dc:creator>Venkateswaran, K.</dc:creator>
<dc:creator>Beheshti, A.</dc:creator>
<dc:date>2022-02-10</dc:date>
<dc:identifier>doi:10.1101/2022.02.07.479455</dc:identifier>
<dc:title><![CDATA[Machine learning algorithm to characterize antimicrobial resistance associated with the International Space Station surface microbiome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-02-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.02.08.479612v1?rss=1">
<title>
<![CDATA[
Maternally inherited siRNAs initiate piRNA cluster formation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.02.08.479612v1?rss=1</link>
<description><![CDATA[
PIWI-interacting RNAs (piRNAs) guide repression of transposable elements in germlines of animals. In Drosophila, piRNAs are produced from heterochromatic genomic loci, called piRNA clusters, that act as a repositories of information about genome invaders. piRNA generation by dual-strand clusters depend on the chromatin-bound Rhino-Deadlock-Cutoff (RDC) complex, which is deposited on clusters guided by piRNAs, forming a feed-forward loop in which piRNAs promote their own biogenesis. However, how piRNA clusters are formed initially, before cognate piRNAs are present, remained unknown. Here we report spontaneous de novo formation of a piRNA cluster from repetitive transgenic sequences. We show that cluster formation occurs gradually over several generations and requires continuous trans-generational transmission of small RNAs from mothers to their progeny. We discovered that maternally-supplied siRNAs are responsible for triggering de novo cluster activation in progeny. In contrast, the siRNA pathway is dispensable for cluster function after its establishment. These results revealed an unexpected cross-talk between the siRNA and piRNA pathways and suggest a mechanism for de novo formation of piRNA clusters triggered by production of siRNAs.

Highlights- A transcribed repetitive transgene is spontaneously converted into dual-strand piRNA cluster
- Establishment of piRNA cluster occurs over multiple generations and requires cytoplasmic inheritance of cognate small RNA from mothers
- Cognate siRNAs initiate the activation of piRNA cluster, but are dispensable after its establishment
]]></description>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>He, P.</dc:creator>
<dc:creator>Kanrar, N.</dc:creator>
<dc:creator>Toth, K. F.</dc:creator>
<dc:creator>Aravin, A.</dc:creator>
<dc:date>2022-02-09</dc:date>
<dc:identifier>doi:10.1101/2022.02.08.479612</dc:identifier>
<dc:title><![CDATA[Maternally inherited siRNAs initiate piRNA cluster formation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-02-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.02.12.480214v1?rss=1">
<title>
<![CDATA[
RNA velocity unraveled 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.02.12.480214v1?rss=1</link>
<description><![CDATA[
We perform a thorough analysis of RNA velocity methods, with a view towards understanding the suitability of the various assumptions underlying popular implementations. In addition to providing a self-contained exposition of the underlying mathematics, we undertake simulations and perform controlled experiments on biological datasets to assess workflow sensitivity to parameter choices and underlying biology. Finally, we argue for a more rigorous approach to RNA velocity, and present a framework for Markovian analysis that points to directions for improvement and mitigation of current problems.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Fang, M.</dc:creator>
<dc:creator>Chari, T.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2022-02-13</dc:date>
<dc:identifier>doi:10.1101/2022.02.12.480214</dc:identifier>
<dc:title><![CDATA[RNA velocity unraveled]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-02-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.02.17.480955v1?rss=1">
<title>
<![CDATA[
In situ architecture of human kinetochore-microtubule interface visualized by cryo-electron tomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.02.17.480955v1?rss=1</link>
<description><![CDATA[
Faithful segregation of chromosomes during mitosis relies on a carefully coordinated and intricate interplay between the centromere, kinetochore, and spindle microtubules. Despite its importance, the architecture of this interface remains elusive. Here we used in situ cryo-electron tomography to visualize the native architecture of the kinetochore-microtubule interface in human U2OS cells at different stages of mitosis. We find that the centromere forms a pocket-like structure around kinetochore microtubules. Two morphologically distinct fibrillar densities form end-on and side-on connections to the plus-ends of microtubules within this centromeric pocket. Our data suggest a dynamic kinetochore-microtubule interface with multiple interactions between outer kinetochore components and spindle microtubules.
]]></description>
<dc:creator>Zhao, W.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2022-02-18</dc:date>
<dc:identifier>doi:10.1101/2022.02.17.480955</dc:identifier>
<dc:title><![CDATA[In situ architecture of human kinetochore-microtubule interface visualized by cryo-electron tomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-02-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.02.22.481344v1?rss=1">
<title>
<![CDATA[
Neuromuscular embodiment of feedback control elements in Drosophila flight 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.02.22.481344v1?rss=1</link>
<description><![CDATA[
While insects like Drosophila are flying, aerodynamic instabilities require that they make millisecond-timescale adjustments to their wing motion to stay aloft and on course. These stabilization reflexes can be modeled as a proportional-integral (PI) controller; however, it is unclear how such control might be instantiated in insects at the level of muscles and neurons. Here, we show that the b1 and b2 motor units--prominent components of the flys steering muscles system--modulate specific elements of the PI controller: the angular displacement (integral, I) and angular velocity (proportional, P), respectively. Moreover, these effects are observed only during the stabilization of pitch. Our results provide evidence for an organizational principle in which each muscle contributes to a specific functional role in flight control, a finding that highlights the power of using top-down behavioral modeling to guide bottom-up cellular manipulation studies.
]]></description>
<dc:creator>Whitehead, S. C.</dc:creator>
<dc:creator>Leone, S.</dc:creator>
<dc:creator>Lindsay, T.</dc:creator>
<dc:creator>Meiselman, M. R.</dc:creator>
<dc:creator>Cowan, N.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:creator>Yapici, N.</dc:creator>
<dc:creator>Stern, D.</dc:creator>
<dc:creator>Shirangi, T.</dc:creator>
<dc:creator>Cohen, I.</dc:creator>
<dc:date>2022-02-24</dc:date>
<dc:identifier>doi:10.1101/2022.02.22.481344</dc:identifier>
<dc:title><![CDATA[Neuromuscular embodiment of feedback control elements in Drosophila flight]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-02-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.02.24.481226v1?rss=1">
<title>
<![CDATA[
Three Mutations Convert the Selectivity of a Protein Sensor From Nicotinic Agonists to S-Methadone For Use in Cells, Organelles, and Biofluids 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.02.24.481226v1?rss=1</link>
<description><![CDATA[
We report a reagentless, intensity-based S-methadone fluorescent sensor, iS-methadoneSnFR, consisting of a circularly permuted GFP inserted within the sequence of a mutated bacterial periplasmic binding protein (PBP). We evolved a previously reported nicotine-binding PBP to become a selective S-methadone-binding sensor, via three mutations in the PBPs second shell and hinge regions. iS-methadoneSnFR displays the necessary sensitivity, kinetics, and selectivity - notably enantioselectivity against R-methadone - for biological applications. Robust iS-methadoneSnFR responses in human sweat and saliva and mouse serum enable diagnostic uses. Expression and imaging in mammalian cells demonstrate that S-methadone enters at least two organelles and undergoes acid trapping in the Golgi apparatus, where opioid receptors can signal. This work shows a straightforward strategy in adapting existing PBPs to serve real-time applications ranging from subcellular to personal pharmacokinetics.
]]></description>
<dc:creator>Muthusamy, A. K.</dc:creator>
<dc:creator>Kim, C. H.</dc:creator>
<dc:creator>Virgil, S. C.</dc:creator>
<dc:creator>Knox, H. J.</dc:creator>
<dc:creator>Marvin, J. S.</dc:creator>
<dc:creator>Nichols, A. L.</dc:creator>
<dc:creator>Cohen, B. N.</dc:creator>
<dc:creator>Dougherty, D. A.</dc:creator>
<dc:creator>Looger, L. L.</dc:creator>
<dc:creator>Lester, H. A.</dc:creator>
<dc:date>2022-02-26</dc:date>
<dc:identifier>doi:10.1101/2022.02.24.481226</dc:identifier>
<dc:title><![CDATA[Three Mutations Convert the Selectivity of a Protein Sensor From Nicotinic Agonists to S-Methadone For Use in Cells, Organelles, and Biofluids]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-02-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.02.25.482050v1?rss=1">
<title>
<![CDATA[
Multi-omic analysis along the gut-brain axis points to a functional architecture of autism 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.02.25.482050v1?rss=1</link>
<description><![CDATA[
Autism is a highly heritable neurodevelopmental disorder characterized by heterogeneous cognitive, behavioral and communication impairments. Disruption of the gut-brain axis (GBA) has been implicated in autism, with dozens of cross-sectional microbiome and other omic studies revealing autism-specific profiles along the GBA albeit with little agreement in composition or magnitude. To explore the functional architecture of autism, we developed an age and sex-matched Bayesian differential ranking algorithm that identified autism-specific profiles across 10 cross-sectional microbiome datasets and 15 other omic datasets, including dietary patterns, metabolomics, cytokine profiles, and human brain expression profiles. The analysis uncovered a highly significant, functional architecture along the GBA that encapsulated the overall heterogeneity of autism phenotypes. This architecture was determined by autism-specific amino acid, carbohydrate and lipid metabolism profiles predominantly encoded by microbial species in the genera Prevotella, Enterococcus, Bifidobacterium, and Desulfovibrio, and was mirrored in brain-associated gene expression profiles and restrictive dietary patterns in individuals with autism. Pro-inflammatory cytokine profiling and virome association analysis further supported the existence of an autism-specific architecture associated with particular microbial genera. Re-analysis of a longitudinal intervention study in autism recapitulated the cross-sectional profiles, and showed a strong association between temporal changes in microbiome composition and autism symptoms. Further elucidation of the functional architecture of autism, including of the role the microbiome plays in it, will require deep, multi-omic longitudinal intervention studies on well-defined stratified cohorts to support causal and mechanistic inference.
]]></description>
<dc:creator>Morton, J. T.</dc:creator>
<dc:creator>Jin, D.-m.</dc:creator>
<dc:creator>Mills, R.</dc:creator>
<dc:creator>Shao, Y.</dc:creator>
<dc:creator>Rahman, G.</dc:creator>
<dc:creator>Harold-Berding, K.</dc:creator>
<dc:creator>Needham, B. D.</dc:creator>
<dc:creator>Zurita, M. F.</dc:creator>
<dc:creator>David, M.</dc:creator>
<dc:creator>Averina, O.</dc:creator>
<dc:creator>Kovtun, A.</dc:creator>
<dc:creator>Noto, A.</dc:creator>
<dc:creator>Mussap, M.</dc:creator>
<dc:creator>Wang, M.</dc:creator>
<dc:creator>Frank, D.</dc:creator>
<dc:creator>Li, E.</dc:creator>
<dc:creator>Zhou, W.</dc:creator>
<dc:creator>Fanos, V.</dc:creator>
<dc:creator>Danilenko, V.</dc:creator>
<dc:creator>Wall, D. P.</dc:creator>
<dc:creator>Cardenas, P. A.</dc:creator>
<dc:creator>Baldeon, M.</dc:creator>
<dc:creator>xavier, r. j.</dc:creator>
<dc:creator>Mazmanian, S.</dc:creator>
<dc:creator>Knight, R.</dc:creator>
<dc:creator>Gilbert, J.</dc:creator>
<dc:creator>Donovan, S.</dc:creator>
<dc:creator>Lawley, T.</dc:creator>
<dc:creator>Carpenter, B.</dc:creator>
<dc:creator>Bonneau, R.</dc:creator>
<dc:creator>Taroncher-Oldenburg, G.</dc:creator>
<dc:date>2022-02-26</dc:date>
<dc:identifier>doi:10.1101/2022.02.25.482050</dc:identifier>
<dc:title><![CDATA[Multi-omic analysis along the gut-brain axis points to a functional architecture of autism]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-02-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.02.26.482105v1?rss=1">
<title>
<![CDATA[
Enabling spatiotemporal regulation within biomaterials using DNA reaction- diffusion waveguides 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.02.26.482105v1?rss=1</link>
<description><![CDATA[
In multicellular organisms, cells and tissues coordinate biochemical signal propagation across length scales spanning microns to meters. Endowing synthetic materials with similar capacities for coordinated signal propagation could allow these systems to adaptively regulate themselves across space and over time. Here we combine ideas from cell signaling and electronic circuitry to design a biochemical waveguide that transmits information in the form of a concentration of a DNA species on a directed path. The waveguide can be seamlessly integrated into a soft material because there is virtually no difference between the chemical or physical properties of the waveguide and the material it is embedded within. We propose the design of DNA strand displacement reactions to construct the system and, using reaction-diffusion models, identify kinetic and diffusive parameters that enable super-diffusive transport of DNA species via autocatalysis. Finally, to support experimental waveguide implementation, we show how a sink reaction could mitigate the spurious amplification of an autocatalyst within the waveguide, allowing for controlled waveguide triggering. Chemical waveguides could facilitate the design of synthetic biomaterials with distributed sensing machinery integrated throughout their structure and enable coordinated self-regulating programs triggered by changing environmental conditions.
]]></description>
<dc:creator>Dorsey, P. J.</dc:creator>
<dc:creator>Scalise, D.</dc:creator>
<dc:creator>Schulman, R.</dc:creator>
<dc:date>2022-02-28</dc:date>
<dc:identifier>doi:10.1101/2022.02.26.482105</dc:identifier>
<dc:title><![CDATA[Enabling spatiotemporal regulation within biomaterials using DNA reaction- diffusion waveguides]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-02-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.02.28.482278v1?rss=1">
<title>
<![CDATA[
Reconstructing the ancestral vertebrate brain using a lamprey neural cell type atlas 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.02.28.482278v1?rss=1</link>
<description><![CDATA[
The vertebrate brain emerged more than [~]500 million years ago in common evolutionary ancestors. To systematically trace its cellular and molecular origins, we established a spatially resolved cell type atlas of the entire brain of the sea lamprey - a jawless species whose phylogenetic position affords the reconstruction of ancestral vertebrate traits - based on extensive single-cell RNA-seq and in situ sequencing data. Comparisons of this atlas to neural data from the mouse and other jawed vertebrates unveiled various shared features that enabled the reconstruction of the core cell type composition, tissue structures, and gene expression programs of the ancestral brain. However, our analyses also revealed key tissues and cell types that arose later in evolution. For example, the ancestral vertebrate brain was likely devoid of cerebellar cell types and oligodendrocytes (myelinating cells); our data suggest that the latter emerged from astrocyte-like evolutionary precursors on the jawed vertebrate lineage. Our work illuminates the cellular and molecular architecture of the ancestral vertebrate brain and provides a foundation for exploring its diversification during evolution.
]]></description>
<dc:creator>Lamanna, F.</dc:creator>
<dc:creator>Hervas-Sotomayor, F.</dc:creator>
<dc:creator>Oel, A. P.</dc:creator>
<dc:creator>Jandzik, D.</dc:creator>
<dc:creator>Sobrido-Camean, D.</dc:creator>
<dc:creator>Martik, M. L.</dc:creator>
<dc:creator>Green, S. A.</dc:creator>
<dc:creator>Brüning, T.</dc:creator>
<dc:creator>Mössinger, K.</dc:creator>
<dc:creator>Schmidt, J.</dc:creator>
<dc:creator>Schneider, C.</dc:creator>
<dc:creator>Sepp, M.</dc:creator>
<dc:creator>Murat, F.</dc:creator>
<dc:creator>Smith, J. J.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>Rodicio, M. C.</dc:creator>
<dc:creator>Barreiro-Iglesias, A.</dc:creator>
<dc:creator>Meulemans Medeiros, D.</dc:creator>
<dc:creator>Arendt, D.</dc:creator>
<dc:creator>Kaessmann, H.</dc:creator>
<dc:date>2022-03-01</dc:date>
<dc:identifier>doi:10.1101/2022.02.28.482278</dc:identifier>
<dc:title><![CDATA[Reconstructing the ancestral vertebrate brain using a lamprey neural cell type atlas]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.01.482452v1?rss=1">
<title>
<![CDATA[
Structural motifs for subtype-specific pH-sensitive gating of vertebrate otopetrin proton channels 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.01.482452v1?rss=1</link>
<description><![CDATA[
Otopetrin (OTOP) channels are proton-selective ion channels conserved among vertebrates and invertebrates and with no structural similarity to other ion channels. There are three vertebrate OTOP channels (OTOP1, OTOP2, and OTOP3), of which one (OTOP1), functions as a sour taste receptor. Whether OTOP channels are gated by, as well as permeating, protons was not known. Here, by comparing functional properties of the three vertebrate proton channels with patch-clamp recording and cytosolic pH microfluorimetry, we provide evidence that each is gated by external protons. OTOP1 and OTOP3 are both activated by extracellular protons, with a sharp threshold of pHe <6.0 and 5.5 respectively, while OTOP2 is negatively gated by protons, and more conductive at alkaline extracellular pH (>pH 9.0). Strikingly, we found that we could change pH-sensitive gating of OTOP2 and OTOP3 channels by swapping extracellular linkers that connect transmembrane domains. Swaps of linkers within the N domain changed the relative conductance at alkaline pH, while swaps within the C domain tended to change the rates of OTOP3 current activation. We conclude that members of the OTOP channel family are proton-gated (acid-sensitive) proton channels and that the gating apparatus is distributed across multiple extracellular regions within both the N and C domains of the channels. In addition to the taste system, OTOP channels are found in the vestibular and digestive systems, where pH sensitivity may be tuned to specific functions.
]]></description>
<dc:creator>Teng, B.</dc:creator>
<dc:creator>Kaplan, J.</dc:creator>
<dc:creator>Liang, Z.</dc:creator>
<dc:creator>Krieger, Z.</dc:creator>
<dc:creator>Tu, Y.-H.</dc:creator>
<dc:creator>Burendei, B.</dc:creator>
<dc:creator>Ward, A. B.</dc:creator>
<dc:creator>Liman, E.</dc:creator>
<dc:date>2022-03-01</dc:date>
<dc:identifier>doi:10.1101/2022.03.01.482452</dc:identifier>
<dc:title><![CDATA[Structural motifs for subtype-specific pH-sensitive gating of vertebrate otopetrin proton channels]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.04.483053v1?rss=1">
<title>
<![CDATA[
Anthroponumbers.org: A Quantitative Database Of Human Impacts on Planet Earth 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.04.483053v1?rss=1</link>
<description><![CDATA[
The Human Impacts Database (www.anthroponumbers.org) is a curated searchable resource housing quantitative data relating to the diverse anthropogenic impacts on our planet, with topics ranging from sea level rise, to livestock populations, greenhouse gas emissions, fertilizer use, and beyond. Each entry in the database relates a quantitative value (or a time-series of values) along with clear referencing of the primary source, the method of measurement or estimation, an assessment of uncertainty, links to the underlying data, as well as a permanent identifier called an Human Impacts ID ("HuID"). While there are other databases that house some of these values, they are typically focused on a single topic area like energy usage or greenhouse gas emissions. The Human Impacts Database provides centralized access to quantitative information about the myriad ways in which humans impact the Earth, giving links to more specialized databases for interested readers. Here, we outline the structure of the database and describe our curation procedures. Finally, we use this database to generate a graphical summary of the current state of human impacts on the Earth, illustrating both their numerical values and their dense interconnections.

The Bigger PictureOver the last 10,000 years, human activities have transformed the Earth through farming, forestry, mining and industry. The complex results of these activities are now observed and quantified as "human impacts" on Earths atmosphere, oceans, biosphere and geochemistry. While myriad studies have explored facets of human impacts on the planet, they are necessarily technical and often tightly-focused. Thus, finding reliable quantitative information requires a significant investment of time to assess each quantity, its methods of determination, and associated uncertainty. We present the Human Impacts Database (www.anthroponumbers.org), which houses a diverse array of such quantities. We review a subset of these values and how they help build intuition for understanding the Earth-human system. While collation alone does not tell us how to best ameliorate human impacts, we contend that any future plans should be made in light of a quantitative understanding of the interconnected ways in which humans impact the planet.
]]></description>
<dc:creator>Chure, G.</dc:creator>
<dc:creator>Banks, R. A.</dc:creator>
<dc:creator>Flamholz, A. I.</dc:creator>
<dc:creator>Sarai, N. S.</dc:creator>
<dc:creator>Kamb, M.</dc:creator>
<dc:creator>Lopez-Gomez, I.</dc:creator>
<dc:creator>Bar-On, Y.</dc:creator>
<dc:creator>Milo, R.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2022-03-07</dc:date>
<dc:identifier>doi:10.1101/2022.03.04.483053</dc:identifier>
<dc:title><![CDATA[Anthroponumbers.org: A Quantitative Database Of Human Impacts on Planet Earth]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.07.482900v1?rss=1">
<title>
<![CDATA[
Automated reconstruction of dendritic and axonal arbors reveals molecular correlates of neuroanatomy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.07.482900v1?rss=1</link>
<description><![CDATA[
AbstractNeuronal anatomy is central to the organization and function of brain cell types. However, anatomical variability within apparently homogeneous populations of cells can obscure such insights. Here, we report large-scale automation of neuronal morphology reconstruction and analysis on a dataset of 813 inhibitory neurons characterized using the Patch-seq method, which enables measurement of multiple properties from individual neurons, including local morphology and transcriptional signature. We demonstrate that these automated reconstructions can be used in the same manner as manual reconstructions to understand the relationship between some, but not all, cellular properties used to define cell types. We uncover gene expression correlates of laminar innervation on multiple transcriptomically defined neuronal subclasses and types. In particular, our results reveal correlates of the variability in Layer 1 (L1) axonal innervation in a transcriptomically defined subpopulation of Martinotti cells in the adult mouse neocortex.
]]></description>
<dc:creator>Gliko, O.</dc:creator>
<dc:creator>Mallory, M.</dc:creator>
<dc:creator>Dalley, R.</dc:creator>
<dc:creator>Gala, R.</dc:creator>
<dc:creator>Gornet, J.</dc:creator>
<dc:creator>Zeng, H.</dc:creator>
<dc:creator>Sorensen, S.</dc:creator>
<dc:creator>Sumbul, U.</dc:creator>
<dc:date>2022-03-08</dc:date>
<dc:identifier>doi:10.1101/2022.03.07.482900</dc:identifier>
<dc:title><![CDATA[Automated reconstruction of dendritic and axonal arbors reveals molecular correlates of neuroanatomy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.10.483309v1?rss=1">
<title>
<![CDATA[
Photoacoustic imaging reveals mechanisms of rapid-acting insulin formulations dynamics at the injection site 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.10.483309v1?rss=1</link>
<description><![CDATA[
ObjectiveUltra-rapid insulin formulations control postprandial hyperglycemia; however, inadequate understanding of injection site absorption mechanisms is limiting further advancement. We used photoacoustic imaging to investigate the injection site dynamics of dye-labeled insulin lispro in the Humalog(R) and Lyumjev(R) formulations using the murine ear cutaneous model and correlated it with results from unlabeled insulin lispro in pig subcutaneous injection model.

MethodsWe employed dual-wavelength optical-resolution photoacoustic microscopy to study the absorption and diffusion of the near-infrared dye-labeled insulin lispro in the Humalog and Lyumjev formulations in mouse ears. We mathematically modeled the experimental data to calculate the absorption rate constants and diffusion coefficients. We studied the pharmacokinetics of the unlabeled insulin lispro in both the Humalog and Lyumjev formulations as well as a formulation lacking both the zinc and phenolic preservative in pigs. The association state of insulin lispro in each of the formulations was characterized using SV-AUC and NMR spectroscopy.

ResultsThrough experiments using murine and swine models, we show that the hexamer dissociation rate of insulin lispro is not the absorption rate-limiting step. We demonstrated that the excipients in the Lyumjev formulation produce local tissue expansion and speed both insulin diffusion and microvascular absorption. We also show that the diffusion of insulin lispro at the injection site drives its initial absorption; however, the rate at which the insulin lispro crosses the blood vessels is its overall absorption rate-limiting step.

ConclusionsThis study provides insights into injection site dynamics of insulin lispro and the impact of formulation excipients. It also demonstrates photoacoustic microscopy as a promising tool for studying protein therapeutics. The results from this study address critical questions around the subcutaneous behavior of insulin lispro and the formulation excipients, which could be useful to make faster and better controlled insulin formulations in the future.

HighlightsO_LIHexamer dissociation is not the absorption rate-limiting step for insulin lispro
C_LIO_LILyumjev excipients enhance insulin microvascular absorption and diffusion
C_LIO_LIVascular endothelial transit determines the overall absorption for insulin lispr
C_LIO_LIInsulin diffusion studied for the first time at the injection site of live animals
C_LIO_LIIn vivo imaging is a powerful tool to study injection site dynamics
C_LI
]]></description>
<dc:creator>Khadria, A.</dc:creator>
<dc:creator>Paavola, C. D.</dc:creator>
<dc:creator>Maslov, K.</dc:creator>
<dc:creator>Valenzuela, F. A.</dc:creator>
<dc:creator>Sperry, A. E.</dc:creator>
<dc:creator>Cox, A. L.</dc:creator>
<dc:creator>Cao, R.</dc:creator>
<dc:creator>Shi, J.</dc:creator>
<dc:creator>Brown-Augsburger, P. L.</dc:creator>
<dc:creator>Lozano, E.</dc:creator>
<dc:creator>Blankenship, R. L.</dc:creator>
<dc:creator>Majumdar, R.</dc:creator>
<dc:creator>Bradley, S. A.</dc:creator>
<dc:creator>Beals, J. M.</dc:creator>
<dc:creator>Oladipupo, S. S.</dc:creator>
<dc:creator>Wang, L. V.</dc:creator>
<dc:date>2022-03-13</dc:date>
<dc:identifier>doi:10.1101/2022.03.10.483309</dc:identifier>
<dc:title><![CDATA[Photoacoustic imaging reveals mechanisms of rapid-acting insulin formulations dynamics at the injection site]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.11.484052v1?rss=1">
<title>
<![CDATA[
Visualization of mRNA Expression in Pseudomonas aeruginosa Aggregates Reveals Spatial Patterns of Fermentative and Denitrifying Metabolism 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.11.484052v1?rss=1</link>
<description><![CDATA[
Gaining insight into the behavior of bacteria at the single cell level is important given that heterogeneous microenvironments strongly influence microbial physiology. The hybridization chain reaction (HCR) is a technique that provides in situ molecular signal amplification, enabling simultaneous mapping of multiple target RNAs at small spatial scales. To refine this method for biofilm applications, we designed and validated new probes to visualize expression of key catabolic genes in Pseudomonas aeruginosa aggregates. In addition to using existing probes for the dissimilatory nitrate reductase (narG), we developed probes for a terminal oxidase (ccoN1), nitrite reductase (nirS), nitrous oxide reductase (nosZ), and acetate kinase (ackA). These probes can be used to determine gene expression levels both in liquid culture and in biofilms. Using these probes, we quantified gene expression across oxygen gradients in aggregate populations grown using the agar block biofilm assay (ABBA). We observed distinct patterns of catabolic gene expression, with upregulation occurring in particular ABBA regions both within individual aggregates and over the aggregate population. Aerobic respiration (ccoN1) showed peak expression under oxic conditions, whereas fermentation (ackA) showed peak expression in the anoxic cores of high metabolic activity aggregates near the air-agar interface. Denitrification genes narG, nirS, and nosZ showed peak expression in hypoxic and anoxic regions, although nirS expression was much stronger in anoxic environments compared to other denitrification genes. These results reveal that the microenvironment correlates with catabolic gene expression in aggregates, and demonstrate the utility of HCR in unveiling cellular activities at the microscale in heterogeneous populations.

ImportanceTo understand bacteria in diverse contexts we must understand the variations in behaviors and metabolisms they express spatiotemporally. Populations of bacteria are known to be heterogeneous, but the ways this variation manifests can be challenging to characterize due to technical limitations. By focusing on energy conservation, we demonstrate that HCR v3.0 can visualize nuances in gene expression, allowing us to understand how metabolism in Pseudomonas aeruginosa biofilms responds to microenvironmental variation at high spatial resolution. We validated probes for four catabolic genes: a constitutively expressed oxidase, acetate kinase, nitrite reductase, and nitrous oxide reductase. We showed that the genes for different modes of metabolism are expressed in overlapping but distinct subpopulations according to oxygen concentrations in a predictable fashion. The spatial transcriptomic technique described here has the potential to be used to map microbial activities across diverse environments.
]]></description>
<dc:creator>Livingston, J.</dc:creator>
<dc:creator>Spero, M. A.</dc:creator>
<dc:creator>Lonergan, Z. R.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2022-03-12</dc:date>
<dc:identifier>doi:10.1101/2022.03.11.484052</dc:identifier>
<dc:title><![CDATA[Visualization of mRNA Expression in Pseudomonas aeruginosa Aggregates Reveals Spatial Patterns of Fermentative and Denitrifying Metabolism]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.13.484157v1?rss=1">
<title>
<![CDATA[
Virgin Birth: A genetic basis for facultative parthenogenesis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.13.484157v1?rss=1</link>
<description><![CDATA[
Sexual reproduction evolved 1-2 billion years ago and underlies the biodiversity of our planet. Nevertheless, devolution of sexual into asexual reproduction can occur across all phyla of the animal kingdom. The genetic basis for how parthenogenesis can arise is completely unknown. To understand the mechanism and benefits of parthenogenesis, we have sequenced the genome of the facultative parthenogen, Drosophila mercatorum, and compared its organisation and expression pattern during parthenogenetic or sexual reproduction. We identified three genes, desat2, Myc, and polo in parthenogenetic D. mercatorum that when mis-regulated in a non-parthenogenetic species, D. melanogaster, enable facultative parthenogenetic reproduction. This simple genetic switch leads us to propose that sporadic facultative parthenogenesis could evolve as an  escape route preserving the genetic lineage in the face of sexual isolation.
]]></description>
<dc:creator>Braun, A. L.</dc:creator>
<dc:creator>Fabian, D. K.</dc:creator>
<dc:creator>Garrison, E.</dc:creator>
<dc:creator>Glover, D. M.</dc:creator>
<dc:date>2022-03-14</dc:date>
<dc:identifier>doi:10.1101/2022.03.13.484157</dc:identifier>
<dc:title><![CDATA[Virgin Birth: A genetic basis for facultative parthenogenesis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.16.484662v1?rss=1">
<title>
<![CDATA[
A naturally arising broad and potent CD4-binding site antibody with low somatic mutation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.16.484662v1?rss=1</link>
<description><![CDATA[
The induction of broadly neutralizing antibodies (bNAbs) is a potential strategy for a vaccine against HIV-1. However, most bNAbs exhibit features such as unusually high somatic hypermutation, including insertions and deletions, which make their induction challenging. VRC01-class bNAbs exhibit extraordinary breadth and potency, but also rank among the most highly somatically-mutated bNAbs. Here we describe a VRC01-class antibody isolated from a viremic controller, BG24, that has less than half the mutations of most other relatives of its class, while achieving comparable breadth and potency. A 3.8 [A] X-ray crystal structure of a BG24-BG505 Env trimer complex revealed conserved contacts at the gp120 interface characteristic of the VRC01-class Abs, despite lacking common CDR3 sequence motifs. The existence of moderately-mutated CD4-binding site (CD4bs) bNAbs such as BG24 provides a simpler blueprint for CD4bs antibody induction by a vaccine, raising the prospect that such an induction might be feasible with a germline-targeting approach.

TeaserAn anti-HIV-1 antibody with comparable neutralization breadth and potency to similarly-classed antibodies, with half as many mutations.
]]></description>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Schoofs, T.</dc:creator>
<dc:creator>Gnanapragasam, P. N. P.</dc:creator>
<dc:creator>Golijanin, J.</dc:creator>
<dc:creator>Huey-Tubman, K. E.</dc:creator>
<dc:creator>Gruell, H.</dc:creator>
<dc:creator>Schommers, P.</dc:creator>
<dc:creator>Suh-Toma, N.</dc:creator>
<dc:creator>Lee, Y. E.</dc:creator>
<dc:creator>Lorenzi, J. C. C.</dc:creator>
<dc:creator>Piechocka-Trocha, A.</dc:creator>
<dc:creator>Scheid, J. F.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Walker, B. D.</dc:creator>
<dc:creator>Seaman, M. S.</dc:creator>
<dc:creator>Klein, F.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2022-03-18</dc:date>
<dc:identifier>doi:10.1101/2022.03.16.484662</dc:identifier>
<dc:title><![CDATA[A naturally arising broad and potent CD4-binding site antibody with low somatic mutation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.16.484680v1?rss=1">
<title>
<![CDATA[
Stress-tolerant, recyclable, and autonomously renewable biocatalyst platform enabled by engineered bacterial spores 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.16.484680v1?rss=1</link>
<description><![CDATA[
Here, we describe a stress-tolerant, recyclable, and autonomously renewable biocatalyst platform based on T7 RNA polymerase-enabled high-density protein display on bacterial spores (TIED). TIED uses high-level T7 RNA polymerase-driven expression of recombinant proteins specifically in sporulating cells to allow spontaneous assembly of recombinant fusion proteins on B. subtilis spore surface. TIED enables a high loading density in the range of 106-107 recombinant enzymes per spore, robust catalytic activities of displayed enzymes comparable to the respective free enzymes, and enhanced kinetic stability of displayed enzymes in methanol and elevated temperatures. Further, we demonstrate TIED-enzymes to be not only recyclable, but fully renewable after loss of activity through induction of germination and sporulation, enabling perpetual reuse of these immobilized biocatalysts.

Graphical abstract

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=126 SRC="FIGDIR/small/484680v1_ufig1.gif" ALT="Figure 1">
View larger version (46K):
org.highwire.dtl.DTLVardef@6f50d0org.highwire.dtl.DTLVardef@22a9c3org.highwire.dtl.DTLVardef@1b74e9corg.highwire.dtl.DTLVardef@18a11c8_HPS_FORMAT_FIGEXP  M_FIG C_FIG Schematic illustration of the T7 RNA polymerase-enabled high-density protein display (TIED) on bacterial spores and its unique features as a biocatalyst platform.
]]></description>
<dc:creator>Hui, Y.</dc:creator>
<dc:creator>Cui, Z.</dc:creator>
<dc:creator>Sim, S.</dc:creator>
<dc:date>2022-03-17</dc:date>
<dc:identifier>doi:10.1101/2022.03.16.484680</dc:identifier>
<dc:title><![CDATA[Stress-tolerant, recyclable, and autonomously renewable biocatalyst platform enabled by engineered bacterial spores]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.21.484932v1?rss=1">
<title>
<![CDATA[
Periodic spatial patterning with a single morphogen 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.21.484932v1?rss=1</link>
<description><![CDATA[
Multicellular development employs periodic spatial patterning to generate repetitive structures such as digits, vertebrae, and teeth. Turing patterning has long provided a key paradigm for understanding such systems. The simplest Turing systems are believed to require at least two signals, or morphogens, that diffuse and react to spontaneously generate periodic patterns. Here, using mathematical modeling, we show that a minimal circuit comprising an intracellular positive feedback loop and a single diffusible morphogen is sufficient to generate stable, long-range spatially periodic cellular patterns. The model considers cells as discrete entities as a key feature, and incorporates transient boundary conditions. Linear stability analysis reveals that this single-morphogen Turing circuit can support a broad range of spatial wavelengths, including fine-grain patterns similar to those generated by classic lateral inhibition systems. Further, signals emanating from a boundary can initiate and stabilize propagating modes with a well-defined spatial wavelength. Once formed, patterns are self-sustaining and robust to noise. Finally, while noise can disrupt patterning in pre-patterned regions, its disruptive effect can be overcome by a bistable intracellular circuit loop, or by considering patterning in the context of growing tissue. Together, these results show that a single morphogen can be sufficient for robust spatial pattern formation, and should provide a foundation for engineering pattern formation in the emerging field of synthetic developmental biology.
]]></description>
<dc:creator>Wang, S.</dc:creator>
<dc:creator>Garcia-Ojalvo, J.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:date>2022-03-22</dc:date>
<dc:identifier>doi:10.1101/2022.03.21.484932</dc:identifier>
<dc:title><![CDATA[Periodic spatial patterning with a single morphogen]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.25.485875v1?rss=1">
<title>
<![CDATA[
Mosaic RBD nanoparticles protect against multiple sarbecovirus challenges in animal models 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.25.485875v1?rss=1</link>
<description><![CDATA[
To combat future SARS-CoV-2 variants and spillovers of SARS-like betacoronaviruses (sarbecoviruses) threatening global health, we designed mosaic nanoparticles presenting randomly-arranged sarbecovirus spike receptor-binding domains (RBDs) to elicit antibodies against conserved/relatively-occluded, rather than variable/immunodominant/exposed, epitopes. We compared immune responses elicited by mosaic-8 (SARS-CoV-2 and seven animal sarbecoviruses) and homotypic (only SARS-CoV-2) RBD-nanoparticles in mice and macaques, observing stronger responses elicited by mosaic-8 to mismatched (not on nanoparticles) strains including SARS-CoV and animal sarbecoviruses. Mosaic-8 immunization showed equivalent neutralization of SARS-CoV-2 variants including Omicron and protected from SARS-CoV-2 and SARS-CoV challenges, whereas homotypic SARS-CoV-2 immunization protected only from SARS-CoV-2 challenge. Epitope mapping demonstrated increased targeting of conserved epitopes after mosaic-8 immunization. Together, these results suggest mosaic-8 RBD-nanoparticles could protect against SARS-CoV-2 variants and future sarbecovirus spillovers.
]]></description>
<dc:creator>Cohen, A. A.</dc:creator>
<dc:creator>van Doremalen, N. A.</dc:creator>
<dc:creator>Greaney, A. J.</dc:creator>
<dc:creator>Andersen, H.</dc:creator>
<dc:creator>Sharma, A.</dc:creator>
<dc:creator>Starr, T. N.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>Fan, C.</dc:creator>
<dc:creator>Schulz, J. E.</dc:creator>
<dc:creator>Gnanapragasam, P. N. P.</dc:creator>
<dc:creator>Kakutani, L. M.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Saturday, G.</dc:creator>
<dc:creator>Lee, Y. E.</dc:creator>
<dc:creator>Gao, H.</dc:creator>
<dc:creator>Jette, C. A.</dc:creator>
<dc:creator>Lewis, M. G.</dc:creator>
<dc:creator>Tan, T. K.</dc:creator>
<dc:creator>Townsend, A. R.</dc:creator>
<dc:creator>Bloom, J. D.</dc:creator>
<dc:creator>Munster, V. J.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2022-03-28</dc:date>
<dc:identifier>doi:10.1101/2022.03.25.485875</dc:identifier>
<dc:title><![CDATA[Mosaic RBD nanoparticles protect against multiple sarbecovirus challenges in animal models]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.08.487649v1?rss=1">
<title>
<![CDATA[
Modeling and mechanical perturbations reveal how spatially regulated anchorage gives rise to spatially distinct mechanics across the mammalian spindle 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.08.487649v1?rss=1</link>
<description><![CDATA[
During cell division, the spindle generates force to move chromosomes. In mammals, microtubule bundles called kinetochore-fibers (k-fibers) attach to and segregate chromosomes. To do so, k-fibers must be robustly anchored to the dynamic spindle. We previously developed microneedle manipulation to mechanically challenge k-fiber anchorage, and observed spatially distinct response features revealing the presence of heterogeneous anchorage (Suresh et al. 2020). How anchorage is precisely spatially regulated, and what forces are necessary and sufficient to recapitulate the k-fibers response to force remain unclear. Here, we develop a coarse-grained k-fiber model and combine with manipulation experiments to infer underlying anchorage using shape analysis. By systematically testing different anchorage schemes, we find that forces solely at k-fiber ends are sufficient to recapitulate unmanipulated k-fiber shapes, but not manipulated ones for which lateral anchorage over a 3 m length scale near chromosomes is also essential. Such anchorage robustly preserves k-fiber orientation near chromosomes while allowing pivoting around poles. Anchorage over a shorter length scale cannot robustly restrict pivoting near chromosomes, while anchorage throughout the spindle obstructs pivoting at poles. Together, this work reveals how spatially regulated anchorage gives rise to spatially distinct mechanics in the mammalian spindle, which we propose are key for function.
]]></description>
<dc:creator>Suresh, P.</dc:creator>
<dc:creator>Galstyan, V.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:creator>Dumont, S.</dc:creator>
<dc:date>2022-04-08</dc:date>
<dc:identifier>doi:10.1101/2022.04.08.487649</dc:identifier>
<dc:title><![CDATA[Modeling and mechanical perturbations reveal how spatially regulated anchorage gives rise to spatially distinct mechanics across the mammalian spindle]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.08.487709v1?rss=1">
<title>
<![CDATA[
From Specification to Implementation: Assume-Guarantee Contracts for Synthetic Biology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.08.487709v1?rss=1</link>
<description><![CDATA[
We provide a new perspective on using formal methods to model specifications and synthesize implementations for the design of biological circuits. In synthetic biology, design objectives are rarely described formally. We present an assume-guarantee contract framework to describe biological circuit design objectives as formal specifications. In our approach, these formal specifications are implemented by circuits modeled by ordinary differential equations, yielding a design framework that can be used to design complex synthetic biological circuits at scale. We describe our approach using the design of a biological AND gate as a motivating, running example.
]]></description>
<dc:creator>Pandey, A.</dc:creator>
<dc:creator>Incer, I.</dc:creator>
<dc:creator>Sangiovanni-Vincentelli, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2022-04-11</dc:date>
<dc:identifier>doi:10.1101/2022.04.08.487709</dc:identifier>
<dc:title><![CDATA[From Specification to Implementation: Assume-Guarantee Contracts for Synthetic Biology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.14.488398v1?rss=1">
<title>
<![CDATA[
Specific targeting of plasmids with Argonaute enables genome editing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.14.488398v1?rss=1</link>
<description><![CDATA[
Prokaryotic Argonautes (pAgos) are programmable nucleases involved in cell defense against invading DNA. Recent studies showed that pAgos can bind small single-stranded guide DNAs (gDNAs) to recognize and cleave complementary DNA in vitro. In vivo pAgos preferentially target plasmids, phages and multicopy genetic elements. Here, we reveal that CbAgo nuclease from Clostridium butyricum can be used for genomic DNA cleavage and engineering in bacteria. CbAgo-dependent targeting of genomic loci with plasmid-derived gDNAs promotes recombination between plasmid and chromosomal DNA. Efficient genome cleavage and recombineering depends on the catalytic activity of CbAgo, its interactions with gDNAs, and the extent of homology between plasmid and chromosomal sequences. Specific targeting of plasmids with Argonautes can be used to integrate plasmid-encoded sequences into the chromosome thus enabling genome editing.

One-Sentence SummaryProkaryotic Argonaute nuclease induces DNA interference between plasmid and chromosomal DNA to promote genome recombineering.
]]></description>
<dc:creator>Esyunina, D.</dc:creator>
<dc:creator>Okhtienko, A.</dc:creator>
<dc:creator>Olina, A.</dc:creator>
<dc:creator>Prostova, M.</dc:creator>
<dc:creator>Aravin, A. A.</dc:creator>
<dc:creator>Kulbachiskiy, A.</dc:creator>
<dc:date>2022-04-14</dc:date>
<dc:identifier>doi:10.1101/2022.04.14.488398</dc:identifier>
<dc:title><![CDATA[Specific targeting of plasmids with Argonaute enables genome editing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.19.488776v1?rss=1">
<title>
<![CDATA[
An approximate line attractor in the hypothalamus that encodes an aggressive internal state 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.19.488776v1?rss=1</link>
<description><![CDATA[
The hypothalamus plays a key role in regulating innate behaviors. It is widely believed to function as a system of  labeled lines, containing behavior-specific neurons with characteristic transcriptomic and connectomic profiles. This view however fails to explain why, although activation of estrogen receptor-1 (Esr1) expressing neurons in the ventromedial hypothalamus (VMHvl) promotes aggression, few VMHvl neurons are tuned to attack. To address this paradox, we adopted an unsupervised dynamical systems framework to analyze population activity among VMHvlEsr1 neurons during aggression. We discovered that this activity contains an "integration" dimension exhibiting slow-ramping dynamics and persistent activity that correlates with escalating aggressiveness. These dynamics are implemented as an approximate line attractor in state space. Our analysis suggests a function for VMHvl to encode the intensity of behavior-relevant motive states using line attractors. This view reconciles observational and perturbational studies of VMHvl, and reveals a new mode of neural computation in the hypothalamus.
]]></description>
<dc:creator>Nair, A.</dc:creator>
<dc:creator>Karigo, T.</dc:creator>
<dc:creator>Yang, B.</dc:creator>
<dc:creator>Linderman, S. W.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:creator>Kennedy, A.</dc:creator>
<dc:date>2022-04-19</dc:date>
<dc:identifier>doi:10.1101/2022.04.19.488776</dc:identifier>
<dc:title><![CDATA[An approximate line attractor in the hypothalamus that encodes an aggressive internal state]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.26.489449v1?rss=1">
<title>
<![CDATA[
Enhanced recovery of single-cell RNA-sequencing reads for missing gene expression data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.26.489449v1?rss=1</link>
<description><![CDATA[
Droplet-based 3 single-cell RNA-sequencing (scRNA-seq) methods have proved transformational in characterizing cellular diversity and generating valuable hypotheses throughout biology1,2. Here we outline a common problem with 3 scRNA-seq datasets where genes that have been documented to be expressed with other methods, are either completely missing or are dramatically under-represented thereby compromising the discovery of cell types, states, and genetic mechanisms. We show that this problem stems from three main sources of sequencing read loss: (1) reads mapping immediately 3 to known gene boundaries due to poor 3 UTR annotation; (2) intronic reads stemming from unannotated exons or pre-mRNA; (3) discarded reads due to gene overlaps3. Each of these issues impacts the detection of thousands of genes even in well-characterized mouse and human genomes rendering downstream analysis either partially or fully blind to their expression. We outline a simple three-step solution to recover the missing gene expression data that entails compiling a hybrid pre-mRNA reference to retrieve intronic reads4, resolving gene collision derived read loss through removal of readthrough and premature start transcripts, and redefining 3 gene boundaries to capture false intergenic reads. We demonstrate with mouse brain and human peripheral blood datasets that this approach dramatically increases the amount of sequencing data included in downstream analysis revealing 20 - 50% more genes per cell and incorporates 15-20% more sequencing reads than with standard solutions5. These improvements reveal previously missing biologically relevant cell types, states, and marker genes in the mouse brain and human blood profiling data. Finally, we provide scRNA-seq optimized transcriptomic references for human and mouse data as well as simple algorithmic implementation of these solutions that can be deployed to both thoroughly as well as poorly annotated genomes. Our results demonstrate that optimizing the sequencing read mapping step can significantly improve the analysis resolution as well as biological insight from scRNA-seq. Moreover, this approach warrants a fresh look at preceding analyses of this popular and scalable cellular profiling technology.
]]></description>
<dc:creator>Pool, A.-H.</dc:creator>
<dc:creator>Poldsam, H.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Oka, Y.</dc:creator>
<dc:date>2022-04-27</dc:date>
<dc:identifier>doi:10.1101/2022.04.26.489449</dc:identifier>
<dc:title><![CDATA[Enhanced recovery of single-cell RNA-sequencing reads for missing gene expression data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.27.489800v1?rss=1">
<title>
<![CDATA[
A human embryonic limb cell atlas resolved in space and time 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.27.489800v1?rss=1</link>
<description><![CDATA[
Human limbs emerge during the fourth post-conception week as mesenchymal buds which develop into fully-formed limbs over the subsequent months. Limb development is orchestrated by numerous temporally and spatially restricted gene expression programmes, making congenital alterations in phenotype common. Decades of work with model organisms has outlined the fundamental processes underlying vertebrate limb development, but an in-depth characterisation of this process in humans has yet to be performed. Here we detail the development of the human embryonic limb across space and time, using both single-cell and spatial transcriptomics. We demonstrate extensive diversification of cells, progressing from a restricted number of multipotent progenitors to myriad mature cell states, and identify several novel cell populations, including neural fibroblasts and multiple distinct mesenchymal states. We uncover two waves of human muscle development, each characterised by different cell states regulated by separate gene expression programmes. We identify musculin (MSC) as a key transcriptional repressor maintaining muscle stem cell identity and validate this by performing MSC knock down in human embryonic myoblasts, which results in significant upregulation of late myogenic genes. Through integration of multiple anatomically continuous spatial transcriptomic samples, we spatially map single-cell clusters across a sagittal section of a whole fetal hindlimb. We reveal a clear anatomical segregation between genes linked to brachydactyly and polysyndactyly, and uncover transcriptionally and spatially distinct populations of mesenchyme in the autopod. Finally, we perform scRNA-seq on murine embryonic limbs to facilitate cross-species developmental comparison at single-cell resolution, finding substantial homology between the two species.
]]></description>
<dc:creator>Zhang, B.</dc:creator>
<dc:creator>He, P.</dc:creator>
<dc:creator>Lawrence, J. E.</dc:creator>
<dc:creator>Wang, S.</dc:creator>
<dc:creator>Tuck, E.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>Roberts, K.</dc:creator>
<dc:creator>Kleshchevnikov, V.</dc:creator>
<dc:creator>Mamanova, L.</dc:creator>
<dc:creator>Bolt, L.</dc:creator>
<dc:creator>Polanski, K.</dc:creator>
<dc:creator>Elmentaite, R.</dc:creator>
<dc:creator>Fasouli, E. S.</dc:creator>
<dc:creator>Prete, M.</dc:creator>
<dc:creator>He, X.</dc:creator>
<dc:creator>Yayon, N.</dc:creator>
<dc:creator>Fu, Y.</dc:creator>
<dc:creator>Yang, H.</dc:creator>
<dc:creator>Liang, C.</dc:creator>
<dc:creator>Zhang, H.</dc:creator>
<dc:creator>Fitzpatrick, D.</dc:creator>
<dc:creator>Firth, H.</dc:creator>
<dc:creator>Dean, A.</dc:creator>
<dc:creator>Marioni, J.</dc:creator>
<dc:creator>Barker, R. A.</dc:creator>
<dc:creator>Storer, M. A.</dc:creator>
<dc:creator>Wold, B.</dc:creator>
<dc:creator>Zhang, H.</dc:creator>
<dc:creator>Teichmann, S.</dc:creator>
<dc:date>2022-04-28</dc:date>
<dc:identifier>doi:10.1101/2022.04.27.489800</dc:identifier>
<dc:title><![CDATA[A human embryonic limb cell atlas resolved in space and time]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.29.490034v1?rss=1">
<title>
<![CDATA[
Selenocyanate Derived Se-Incorporation into the Nitrogenase Fe Protein Cluster 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.29.490034v1?rss=1</link>
<description><![CDATA[
The nitrogenase Fe protein mediates ATP-dependent electron transfer to the nitrogenase MoFe protein during nitrogen fixation, in addition to catalyzing MoFe protein independent substrate (CO2) reduction and facilitating MoFe protein metallocluster biosynthesis. The precise role(s) of the Fe protein Fe4S4 cluster in some of these processes remains ill-defined. Herein, we report crystallographic data demonstrating ATP-dependent chalcogenide exchange at the Fe4S4 cluster of the nitrogenase Fe protein when potassium selenocyanate is used as the selenium source. The observed chalcogenide exchange illustrates that this Fe4S4 cluster is capable of core substitution reactions under certain conditions, adding to the Fe proteins repertoire of unique properties.
]]></description>
<dc:creator>Buscagan, T. M.</dc:creator>
<dc:creator>Kaiser, J. T.</dc:creator>
<dc:creator>Rees, D. C.</dc:creator>
<dc:date>2022-04-30</dc:date>
<dc:identifier>doi:10.1101/2022.04.29.490034</dc:identifier>
<dc:title><![CDATA[Selenocyanate Derived Se-Incorporation into the Nitrogenase Fe Protein Cluster]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.05.02.490306v1?rss=1">
<title>
<![CDATA[
Effects of the investigational drug sodium phenylbutyrate-TUDCA (AMX0035) on the transcriptional and metabolic landscape of sporadic ALS fibroblasts 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.05.02.490306v1?rss=1</link>
<description><![CDATA[
ALS is a rapidly progressive, fatal disorder caused by motor neuron degeneration, for which there is a great unmet therapeutic need. AMX0035, a combination of sodium phenylbutyrate (PB) and taurursodiol (TUDCA, Turso), has shown promising results in early ALS clinical trials, but its mechanisms of action remain to be elucidated. To obtain an unbiased landscape of AMX0035 effects we investigated the transcriptomic and metabolomic profiles of primary skin fibroblasts from sporadic ALS patients and healthy controls treated with PB, TUDCA, or PB-TUDCA combination (Combo). Combo changed many more genes and metabolites than either PB or TUDCA individually. Most changes were unique to Combo and affected the expression of genes involved in ALS-relevant pathways, such as nucleocytoplasmic transport, unfolded protein response, mitochondrial function, RNA metabolism, and innate immunity. Weighted gene coexpression network analysis showed that significant correlations between ALS gene expression modules and clinical parameters were abolished by Combo. This study is the first to explore the molecular effects of Combo in ALS patient-derived cells. It shows that Combo has a greater and distinct impact compared to the individual compounds and provides clues to drug targets and mechanisms of actions, which may underlie the benefits of this investigational drug combination.
]]></description>
<dc:creator>Fels, J. A.</dc:creator>
<dc:creator>Dash, J.</dc:creator>
<dc:creator>Leslie, K.</dc:creator>
<dc:creator>Manfredi, G.</dc:creator>
<dc:creator>Kawamata, H.</dc:creator>
<dc:date>2022-05-02</dc:date>
<dc:identifier>doi:10.1101/2022.05.02.490306</dc:identifier>
<dc:title><![CDATA[Effects of the investigational drug sodium phenylbutyrate-TUDCA (AMX0035) on the transcriptional and metabolic landscape of sporadic ALS fibroblasts]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-05-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.05.06.490859v1?rss=1">
<title>
<![CDATA[
Depth normalization for single-cell genomics count data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.05.06.490859v1?rss=1</link>
<description><![CDATA[
Single-cell genomics analysis requires normalization of feature counts that stabilizes variance while accounting for variable cell sequencing depth. We discuss some of the trade-offs present with current widely used methods, and analyze their performance on 526 single-cell RNA-seq datasets. The results lead us to recommend proportional fitting prior to log transformation followed by an additional proportional fitting.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Hallgrimsdottir, I. B.</dc:creator>
<dc:creator>Galvez-Merchan, A.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2022-05-06</dc:date>
<dc:identifier>doi:10.1101/2022.05.06.490859</dc:identifier>
<dc:title><![CDATA[Depth normalization for single-cell genomics count data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-05-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.05.06.490956v1?rss=1">
<title>
<![CDATA[
Fixation Can Change the Appearance of Phase Separation in Living Cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.05.06.490956v1?rss=1</link>
<description><![CDATA[
Fixing cells with paraformaldehyde (PFA) is an essential step in numerous biological techniques as it is thought to preserve a snapshot of biomolecular transactions in living cells. Fixed cell imaging techniques such as immunofluorescence have been widely used to detect liquid-liquid phase separation (LLPS) in vivo. Here, we compared images, before and after fixation, of cells expressing intrinsically disordered proteins that are able to undergo LLPS. Surprisingly, we found that PFA fixation can both enhance and diminish putative LLPS behaviors. For specific proteins, fixation can even cause their droplet-like puncta to artificially appear in cells that do not have any detectable puncta in the live condition. Fixing cells in the presence of glycine, a molecule that modulates fixation rates, can reverse the fixation effect from enhancing to diminishing LLPS appearance. We further established a kinetic model of fixation in the context of dynamic protein-protein interactions. Simulations based on the model suggest that protein localization in fixed cells depends on an intricate balance of protein-protein interaction dynamics, the overall rate of fixation, and notably, the difference between fixation rates of different proteins. Consistent with simulations, live-cell single-molecule imaging experiments showed that a fast overall rate of fixation relative to protein-protein interaction dynamics can minimize fixation artifacts. Our work reveals that PFA fixation changes the appearance of LLPS from living cells, presents a caveat in studying LLPS using fixation-based methods, and suggests a mechanism underlying the fixation artifact.
]]></description>
<dc:creator>Irgen-Gioro, S.</dc:creator>
<dc:creator>Walling, V.</dc:creator>
<dc:creator>Chong, S.</dc:creator>
<dc:date>2022-05-08</dc:date>
<dc:identifier>doi:10.1101/2022.05.06.490956</dc:identifier>
<dc:title><![CDATA[Fixation Can Change the Appearance of Phase Separation in Living Cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-05-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.05.09.491197v1?rss=1">
<title>
<![CDATA[
Single-cell profiling coupled with lineage analysis reveals distinct sacral neural crest contributions to the developing enteric nervous 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.05.09.491197v1?rss=1</link>
<description><![CDATA[
During development, the enteric nervous system (ENS) arises from neural crest cells that emerge from the neural tube, migrate to and along the gut, and colonize the entire intestinal tract. While much of the ENS arises from vagal neural crest cells that originate from the caudal hindbrain, there is a second contribution from the sacral neural crest that migrates from the caudal end of the spinal cord to populate the post-umbilical gut. By coupling single cell transcriptomics with axial-level specific lineage tracing in avian embryos, we compared the contributions between embryonic vagal and sacral neural crest cells to the ENS. The results show that the two neural crest populations form partially overlapping but also complementary subsets of neurons and glia in distinct ganglionic units. In particular, the sacral neural crest cells appear to be the major source of adrenergic/dopaminergic and serotonergic neurons, melanocytes and Schwann cells in the post-umbilical gut. In addition to neurons and glia, the results also reveal sacral neural crest contributions to connective tissue and mesenchymal cells of the gut. These findings highlight the specific properties of the sacral neural crest population in the hindgut and have potential implications for understanding development of the complex nervous system in the hindgut environment that may influence congenital neuropathies.
]]></description>
<dc:creator>Tang, W.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>Jacobs-Li, J.</dc:creator>
<dc:creator>Li, C.</dc:creator>
<dc:date>2022-05-09</dc:date>
<dc:identifier>doi:10.1101/2022.05.09.491197</dc:identifier>
<dc:title><![CDATA[Single-cell profiling coupled with lineage analysis reveals distinct sacral neural crest contributions to the developing enteric nervous]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-05-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.05.17.491718v1?rss=1">
<title>
<![CDATA[
Long-duration and non-invasive photoacoustic imaging of multiple anatomical structures in a live mouse using a single contrast agent 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.05.17.491718v1?rss=1</link>
<description><![CDATA[
Long-duration in vivo simultaneous imaging of multiple anatomical structures is useful for understanding physiological aspects of diseases, informative for molecular optimization in preclinical models, and has potential applications in surgical settings to improve clinical outcomes. Previous studies involving simultaneous imaging of multiple anatomical structures, e.g., blood and lymphatic vessels as well as peripheral nerves and sebaceous glands, have used genetically engineered mice, which require expensive and time-consuming methods. Here, an IgG4 isotype control antibody is labeled with a near-infrared dye and injected into a mouse ear to enable simultaneous visualization of blood and lymphatic vessels, peripheral nerves, and sebaceous glands for up to 3 hours using photoacoustic microscopy. For multiple anatomical structure imaging, peripheral nerves and sebaceous glands are imaged inside the injected dye-labeled antibody mass while the lymphatic vessels are visualized outside the mass. The efficacy of the contrast agent to label and localize deep medial lymphatic vessels and lymph nodes using photoacoustic computed tomography is demonstrated. The capability of a single injectable contrast agent to image multiple structures for several hours will potentially improve preclinical therapeutic optimization, shorten discovery timelines, and enable clinical treatments.
]]></description>
<dc:creator>KHADRIA, A.</dc:creator>
<dc:creator>Paavola, C. D.</dc:creator>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Davis, S. P. X.</dc:creator>
<dc:creator>Grealish, P.</dc:creator>
<dc:creator>Maslov, K.</dc:creator>
<dc:creator>Shi, J.</dc:creator>
<dc:creator>Beals, J. M.</dc:creator>
<dc:creator>Oladipupo, S. S.</dc:creator>
<dc:creator>Wang, L. V.</dc:creator>
<dc:date>2022-05-19</dc:date>
<dc:identifier>doi:10.1101/2022.05.17.491718</dc:identifier>
<dc:title><![CDATA[Long-duration and non-invasive photoacoustic imaging of multiple anatomical structures in a live mouse using a single contrast agent]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-05-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.05.17.492392v1?rss=1">
<title>
<![CDATA[
Efficient querying of genomic databases for single-cell RNA-seq with gget 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.05.17.492392v1?rss=1</link>
<description><![CDATA[
MotivationA recurring challenge in interpreting genomic data is the assessment of results in the context of existing reference databases. Currently, there is no tool implementing automated, easy programmatic access to curated reference information stored in a diverse collection of large, public genomic databases.

Resultsgget is a free and open-source command-line tool and Python package that enables efficient querying of genomic reference databases, such as Ensembl. gget consists of a collection of separate but interoperable modules, each designed to facilitate one type of database querying required for genomic data analysis in a single line of code.

AvailabilityThe manual and source code are available at https://github.com/pachterlab/gget.

Contactlpachter@caltech.edu
]]></description>
<dc:creator>Luebbert, L.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2022-05-19</dc:date>
<dc:identifier>doi:10.1101/2022.05.17.492392</dc:identifier>
<dc:title><![CDATA[Efficient querying of genomic databases for single-cell RNA-seq with gget]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-05-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.05.18.492498v1?rss=1">
<title>
<![CDATA[
Precision motor timing via scalar input fluctuations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.05.18.492498v1?rss=1</link>
<description><![CDATA[
Complex motor skills like playing piano require precise timing over long periods, without errors accumulating between subprocesses like the left and right hand movements. While biological models can produce motor-like sequences, how the brain quenches timing errors is not well understood. Motivated by songbirds, where the left and right brain nuclei governing song sequences do not connect but may receive low-dimensional thalamic input, we present a model where timing errors in an autonomous sequence generator are continually corrected by one-dimensional input fluctuations. We show in a spiking neural network model how such input can rapidly correct temporal offsets in a propagating spike pulse, recapitulating the precise timing seen in songbird brains. In a reduced, more general model, we show that such timing correction emerges when the spatial profile of the input over the sequence sufficiently reflects its temporal fluctuations, yielding time-locking attractors that slow advanced sequences and hasten lagging ones, up to the input timescale. Unlike models without fluctuating input, our model predicts anti-correlated durations of adjacent segments of the output sequence, which we verify in recorded zebra finch songs. This work provides a bioplausible picture of how temporal precision could arise in extended motor sequences and generally how low-dimensional input could continuously coordinate time-varying output signals.

SignificanceComplex motor skills like playing piano require precision timing over long periods, often among multiple components like left and right muscle groups. Although brain-like network models can produce motor-like outputs, timing regulation is not well understood. We introduce a model, inspired by songbird brains, where imprecise timing in a cortical-like system is corrected by a single thalamic input regulating the sequential propagation, or tempo, of cortical activity. This model illuminates a relation between the inputs spatial structure and temporal variation that lets lagging activity hasten and advanced activity slow, which makes a prediction about output timing that we verify in real birdsong. This work reveals a simple, neuroplausible mechanism that may play a role in precision cortical or motor timing.
]]></description>
<dc:creator>Pang, R.</dc:creator>
<dc:creator>Duffy, A.</dc:creator>
<dc:creator>Bell, D.</dc:creator>
<dc:creator>Torok, Z. E.</dc:creator>
<dc:creator>Fairhall, A. L.</dc:creator>
<dc:date>2022-05-19</dc:date>
<dc:identifier>doi:10.1101/2022.05.18.492498</dc:identifier>
<dc:title><![CDATA[Precision motor timing via scalar input fluctuations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-05-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.05.18.492548v1?rss=1">
<title>
<![CDATA[
Metadata retrieval from genomics database with ffq 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.05.18.492548v1?rss=1</link>
<description><![CDATA[
We present a command-line tool, called ffq, for querying user-generated data and metadata from sequence databases. The code can be found here: https://github.com/pachterlab/ffq.
]]></description>
<dc:creator>Galvez-Merchan, A.</dc:creator>
<dc:creator>Min, K. H.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:date>2022-05-19</dc:date>
<dc:identifier>doi:10.1101/2022.05.18.492548</dc:identifier>
<dc:title><![CDATA[Metadata retrieval from genomics database with ffq]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-05-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.05.26.493158v1?rss=1">
<title>
<![CDATA[
Magneto-acoustic protein nanostructures for non-invasive imaging of tissue mechanics in vivo 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.05.26.493158v1?rss=1</link>
<description><![CDATA[
Measuring cellular and tissue mechanics inside intact living organisms is essential for interrogating the roles of force in physiological and disease processes, and is a major goal in the field of mechanobiology. However, existing biosensors for 3D tissue mechanics, primarily based on fluorescent emissions and deformable materials, are limited for in vivo measurement due to the limited light penetration and poor material stability inside intact, living organisms. While magneto-motive ultrasound (MMUS), which uses superparamagnetic nanoparticles as imaging contrast agents, has emerged as a promising modality for real-time in vivo imaging of tissue mechanics, it has poor sensitivity and spatiotemporal resolution. To overcome these limitations, we introduce magneto-gas vesicles (MGVs), a unique class of protein nanostructures based on gas vesicles and magnetic nanoparticles that produces differential ultrasound signals in response to varying mechanical properties of surrounding tissues. These hybrid protein nanostructures significantly improve signal strength and detection sensitivity. Furthermore, MGVs enable non-invasive, long-term, and quantitative measurement of mechanical properties within 3D tissues and organs in vivo. We demonstrated the performance of MGV-based mechano-sensors in vitro, in fibrosis models of organoids, and in vivo in mouse liver fibrosis models.
]]></description>
<dc:creator>Kim, W.-S.</dc:creator>
<dc:creator>Min, S.</dc:creator>
<dc:creator>Kim, S. K.</dc:creator>
<dc:creator>Kang, S.</dc:creator>
<dc:creator>Davis, H.</dc:creator>
<dc:creator>Bar-Zion, A.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Kim, Y. H.</dc:creator>
<dc:creator>An, S.</dc:creator>
<dc:creator>Lee, J.-H.</dc:creator>
<dc:creator>Bae, S. H.</dc:creator>
<dc:creator>Lee, J. G.</dc:creator>
<dc:creator>Kwak, M.</dc:creator>
<dc:creator>Cho, S.-W.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Cheon, J.</dc:creator>
<dc:date>2022-05-27</dc:date>
<dc:identifier>doi:10.1101/2022.05.26.493158</dc:identifier>
<dc:title><![CDATA[Magneto-acoustic protein nanostructures for non-invasive imaging of tissue mechanics in vivo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-05-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.05.30.494051v1?rss=1">
<title>
<![CDATA[
A universal system for streamlined genome integrations with CRISPR-associated transposases 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.05.30.494051v1?rss=1</link>
<description><![CDATA[
Genome engineering tools in bacteria are limited by their targeting abilities, cargo size capacities, and integration efficiencies. Programmable Cas-directed transposons have been shown to bypass these constraints; however, genome integrations with these Cas-directed transposons require a cargo plasmid carrying the desired DNA payload flanked by directed repeat transposon arms. This cloning pre-requisite significantly hinders the modularity and streamlining capabilities of Cas-directed transposon systems, diminishing their utility for genome engineering. Here, we present a system that can robustly integrate a linear DNA payload into the genome of E. coli by employing a Type I-F CRISPR-associated transposon from Vibrio cholerae. This system bypasses the traditional limiting factors of Cas-directed transposons by leveraging oligonucleotide design and nested polymerase chain reactions to reconstitute the transposon arms onto a designated cargo. Our findings demonstrate that this programmable linear integration method has high efficiencies in integrating large DNA payloads across multiple genomic loci.
]]></description>
<dc:creator>Wang, M.</dc:creator>
<dc:creator>Sanfiorenzo, C.</dc:creator>
<dc:creator>Zhang, R. J.</dc:creator>
<dc:creator>Wang, K.</dc:creator>
<dc:date>2022-05-31</dc:date>
<dc:identifier>doi:10.1101/2022.05.30.494051</dc:identifier>
<dc:title><![CDATA[A universal system for streamlined genome integrations with CRISPR-associated transposases]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-05-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.04.494841v1?rss=1">
<title>
<![CDATA[
Anaerobic single particle cryoEM of nitrogenase 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.04.494841v1?rss=1</link>
<description><![CDATA[
The enzyme nitrogenase catalyzes the reduction of dinitrogen to ammonia during biological nitrogen fixation through a mechanism involving the ATP dependent interaction of two component proteins adopting multiple conformational states. To date, high resolution structural information has been provided by X-ray crystallography, which restricts the states that can be accessed to those that can be crystallized. Cryo-electron microscopy (cryoEM) presents a new opportunity for structural characterization of nitrogenase solution structures, and may yield new information on the mechanism of nitrogenase by revealing structures of transient or heterogeneous states. In this study, we present single particle cryoEM structures of the MoFe-nitrogenase endogenously isolated from Azotobacter vinelandii. To maintain the fully reduced cluster states of this oxygen sensitive protein, we prepared samples within an anaerobic chamber and employed specialized conditions to minimize partial disordering of the -subunit at the air-water interface during freezing. Under these conditions, cryoEM structures of the as-isolated MoFe-protein and stabilized MoFe-protein-Fe-protein ADP-AlF4-complex were generally found to closely resemble their corresponding X-ray crystallographic structures. The cryoEM structures did reveal disordering in regions of the MoFe-protein -subunit reminiscent of that observed previously for the {Delta}nifB MoFe-protein lacking the FeMo-cofactor, suggesting that this disorder may reflect functionally relevant dynamics, as well as the possibility of asymmetric binding of the Fe-protein to the MoFe-protein in solution. The methods presented here pave the way toward the capture and interrogation of turnover-relevant nitrogenase states by cryoEM.
]]></description>
<dc:creator>Warmack, R. A.</dc:creator>
<dc:creator>Rees, D. C.</dc:creator>
<dc:date>2022-06-04</dc:date>
<dc:identifier>doi:10.1101/2022.06.04.494841</dc:identifier>
<dc:title><![CDATA[Anaerobic single particle cryoEM of nitrogenase]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.04.494845v1?rss=1">
<title>
<![CDATA[
Pseudoalignment facilitates assignment of error-prone Ultima Genomics reads 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.04.494845v1?rss=1</link>
<description><![CDATA[
We analyze single-cell RNA-seq data sequenced with Ultima Genomics technology and find high error rates in and near homopolymers. To compensate for these errors, we explore the use of pseudoalignment for read assignment, and find that it can perform better than standard read alignment. Our pseudoalignment read assignment for Ultima Genomics data is available as part of the kallisto-bustools kb-python package available at https://github.com/pachterlab/kb_python.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2022-06-05</dc:date>
<dc:identifier>doi:10.1101/2022.06.04.494845</dc:identifier>
<dc:title><![CDATA[Pseudoalignment facilitates assignment of error-prone Ultima Genomics reads]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.05.493862v1?rss=1">
<title>
<![CDATA[
Improved Version of ChETA Promotes Aggression in the Medial Amygdala 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.05.493862v1?rss=1</link>
<description><![CDATA[
The development of optogenetic tools has significantly advanced our understanding of neural circuits and behavior. The medial amygdala, posterior dorsal subdivision (MeApd) is part of a distributed network controlling social behaviors such as mating and aggression. Previous work showed that activation of GABAergic neurons in mouse MeApd using channelrodopsin-2 (ChR2H134R) promoted aggression. In a recent study, Baleisyte et al. (2022) confirmed these findings using the same reagents (i.e. ChR2H134R), but also reported that a different ChR2 variant with faster kinetics--ChETA--inhibited rather than promoted aggression when high laser power, long duration photostimulation conditions were used. As ChETA is known to have a substantially lower photocurrent than ChR2 and other opsins, an improved version of ChETA (i.e. ChR2E123T/T159C; ChETATC) was subsequently developed. ChETATC has larger photocurrents than the original ChETA while maintaining fast kinetics and low plateau depolarization. Here we show that activating MeApd GABAergic neurons using the improved ChETATC promotes aggression, similar to ChR2H134R, suggesting that the results obtained using the original ChETA are not due to a difference in channel kinetics. Furthermore, we found that ChETATC is capable of driving a rapid onset of aggression within 200-300 milliseconds of stimulation, suggesting that this effect reflects direct activation of MeApd GABAergic neurons. We conclude that the different behavioral phenotypes observed using the original ChETA vs. ChETATC and ChR2 likely reflects the weaker photocurrents in ChETA vs. other opsins, and/or the long duration/high power photostimulation conditions used with ChETA. Consistent with this conclusion, the results obtained using ChR2 or ChETATC are complementary to findings from loss-of-functions experiments using optogenetic inhibition, chemogenetic inhibition, and neuronal ablation. These data support a positive-acting role of MeApd Vgat+ neurons in aggression. Our findings, in conjunction with studies of Berndt et al. (2011), suggest that the improved ChETATC should be used when faster kinetics than ChR2 offers are required.
]]></description>
<dc:creator>Hu, R. K.</dc:creator>
<dc:creator>Chen, P. B.</dc:creator>
<dc:creator>Berndt, A.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:creator>Hong, W.</dc:creator>
<dc:date>2022-06-06</dc:date>
<dc:identifier>doi:10.1101/2022.06.05.493862</dc:identifier>
<dc:title><![CDATA[Improved Version of ChETA Promotes Aggression in the Medial Amygdala]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.11.495771v1?rss=1">
<title>
<![CDATA[
Monod: mechanistic analysis of single-cell RNA sequencing count data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.11.495771v1?rss=1</link>
<description><![CDATA[
Single-cell RNA sequencing analysis centers on illuminating cell diversity and understanding the transcriptional mechanisms underlying cellular function. These datasets are large, noisy, and complex. Current analyses prioritize noise removal and dimensionality reduction to tackle these challenges and extract biological insight. We propose an alternative, physical approach to leverage the stochasticity, size, and multimodal nature of these data to explicitly distinguish their biological and technical facets while revealing the underlying regulatory processes. With the Python package Monod, we demonstrate how nascent and mature RNA counts, present in most published datasets, can be meaningfully "integrated" under biophysical models of transcription. By utilizing variation in these modalities, we can identify transcriptional modulation not discernible though changes in average gene expression, quantitatively compare mechanistic hypotheses of gene regulation, analyze transcriptional data from different technologies within a common framework, and minimize the use of opaque or distortive normalization and transformation techniques.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2022-06-12</dc:date>
<dc:identifier>doi:10.1101/2022.06.11.495771</dc:identifier>
<dc:title><![CDATA[Monod: mechanistic analysis of single-cell RNA sequencing count data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.13.496000v1?rss=1">
<title>
<![CDATA[
Dynamic structural adaptations enable the endobiotic predation of bdellovibrio bacteriovorus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.13.496000v1?rss=1</link>
<description><![CDATA[
Bdellovibrio bacteriovorus is an endobiotic microbial predator that offers promise as a living antibiotic for its ability to kill Gram-negative bacteria, including human pathogens. Even after six decades of study, fundamental details of its predation cycle remain mysterious. Here, we used cryo-electron tomography to comprehensively image the lifecycle of B. bacteriovorus at nanometer-scale resolution. In addition to providing the first high-resolution images of predation in a native (hydrated, unstained) state, we also discover several surprising features of the process, including novel macromolecular complexes involved in prey attachment/invasion and a flexible portal structure lining a hole in the prey peptidoglycan that tightly seals the prey outer membrane around the predator during entry. Unexpectedly, we find that B. bacteriovorus does not shed its flagellum during invasion, but rather resorbs it into its periplasm for degradation. Finally, following replication and division in the bdelloplast, we observe a transient and extensive ribosomal lattice on the condensed B. bacteriovorus nucleoid.

Graphical abstract

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/496000v1_ufig1.gif" ALT="Figure 1">
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org.highwire.dtl.DTLVardef@35da74org.highwire.dtl.DTLVardef@19923f1org.highwire.dtl.DTLVardef@106a616org.highwire.dtl.DTLVardef@181f2fb_HPS_FORMAT_FIGEXP  M_FIG C_FIG
]]></description>
<dc:creator>Kaplan, M.</dc:creator>
<dc:creator>Chang, Y.-W.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>Nicolas, W. J.</dc:creator>
<dc:creator>Jewett, A. I.</dc:creator>
<dc:creator>Kreida, S.</dc:creator>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Rettberg, L. A.</dc:creator>
<dc:creator>Maggi, S.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2022-06-13</dc:date>
<dc:identifier>doi:10.1101/2022.06.13.496000</dc:identifier>
<dc:title><![CDATA[Dynamic structural adaptations enable the endobiotic predation of bdellovibrio bacteriovorus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.14.496146v1?rss=1">
<title>
<![CDATA[
Nemacol is a Small Molecule Inhibitor of C. elegans Vesicular Acetylcholine Transporter with Anthelmintic Potential 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.14.496146v1?rss=1</link>
<description><![CDATA[
Nematode parasites of humans and livestock pose a significant burden to human health, economic development, and food security. Anthelmintic drug resistance is widespread among parasites of livestock and many nematode parasites of humans lack effective treatments. Here, we present a nitrophenyl-piperazine scaffold that induces motor defects rapidly in the model nematode Caenorhabditis elegans. We call this scaffold Nemacol and show that it inhibits the vesicular acetylcholine transporter (VAChT), a target recognized by commercial animal and crop health groups as a viable anthelmintic target. We demonstrate that it is possible to create Nemacol analogs that maintain potent in vivo activity whilst lowering their affinity to the mammalian VAChT 10-fold. We also show that Nemacol synergizes with the anthelmintic ivermectin to kill C. elegans. Hence, Nemacol represents a promising new anthelmintic scaffold that acts through an identified viable anthelmintic target.

One sentence summaryA small molecule screen identifies a vesicular acetylcholine transporter inhibitor scaffold that incapacitates parasitic nematodes
]]></description>
<dc:creator>Harrington, S.</dc:creator>
<dc:creator>Pyche, J.</dc:creator>
<dc:creator>Burns, A. R.</dc:creator>
<dc:creator>Spalholz, T.</dc:creator>
<dc:creator>Baker, R. J.</dc:creator>
<dc:creator>Ching, J.</dc:creator>
<dc:creator>Lautens, M.</dc:creator>
<dc:creator>Kulke, D.</dc:creator>
<dc:creator>Deuther-Conrad, W.</dc:creator>
<dc:creator>Brust, P.</dc:creator>
<dc:creator>Roy, P. J.</dc:creator>
<dc:date>2022-06-17</dc:date>
<dc:identifier>doi:10.1101/2022.06.14.496146</dc:identifier>
<dc:title><![CDATA[Nemacol is a Small Molecule Inhibitor of C. elegans Vesicular Acetylcholine Transporter with Anthelmintic Potential]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.16.496161v1?rss=1">
<title>
<![CDATA[
Disrupting cellular memory to overcome drug resistance 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.16.496161v1?rss=1</link>
<description><![CDATA[
Plasticity enables cells to change their gene expression state in the absence of a genetic change. At the single-cell level, these gene expression states can persist for different lengths of time which is a quantitative measurement referred to as gene expression memory. Because plasticity is not encoded by genetic changes, these cell states can be reversible, and therefore, are amenable to modulation by disrupting gene expression memory. However, we currently do not have robust methods to find the regulators of memory or to track state switching in plastic cell populations. Here, we developed a lineage tracing-based technique to quantify gene expression memory and to identify single cells as they undergo cell state transitions. Applied to human melanoma cells, we quantified long-lived fluctuations in gene expression that underlie resistance to targeted therapy. Further, we identified the PI3K and TGF-{beta} pathways as modulators of these state dynamics. Applying the gene expression signatures derived from this technique, we find that these expression states are generalizable to in vivo models and present in scRNA-seq from patient tumors. Leveraging the PI3K and TGF-{beta} pathways as dials on memory between plastic states, we propose a " pretreatment" model in which we first use a PI3K inhibitor to modulate the expression states of the cell population and then apply targeted therapy. This plasticity informed dosing scheme ultimately yields fewer resistant colonies than targeted therapy alone. Taken together, we describe a technique to find modulators of gene expression memory and then apply this knowledge to alter plastic cell states and their connected cell fates.
]]></description>
<dc:creator>Harmange, G.</dc:creator>
<dc:creator>Reyes Hueros, R. A.</dc:creator>
<dc:creator>Schaff, D. L.</dc:creator>
<dc:creator>Emert, B. L.</dc:creator>
<dc:creator>Saint-Antoine, M. M.</dc:creator>
<dc:creator>Nellore, S.</dc:creator>
<dc:creator>Fane, M. E.</dc:creator>
<dc:creator>Alicea, G. M.</dc:creator>
<dc:creator>Weeraratna, A. T.</dc:creator>
<dc:creator>Singh, A.</dc:creator>
<dc:creator>Shaffer, S. M.</dc:creator>
<dc:date>2022-06-17</dc:date>
<dc:identifier>doi:10.1101/2022.06.16.496161</dc:identifier>
<dc:title><![CDATA[Disrupting cellular memory to overcome drug resistance]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.16.496448v1?rss=1">
<title>
<![CDATA[
Spectral neural approximations for models of transcriptional dynamics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.16.496448v1?rss=1</link>
<description><![CDATA[
The advent of high-throughput transcriptomics provides an opportunity to advance mechanistic understanding of transcriptional processes and their connections to cellular function at an un-precedented, genome-wide scale. These transcriptional systems, which involve discrete, stochastic events, are naturally modeled using Chemical Master Equations (CMEs), which can be solved for probability distributions to fit biophysical rates that govern system dynamics. While CME models have been used as standards in fluorescence transcriptomics for decades to analyze single species RNA distributions, there are often no closed-form solutions to CMEs that model multiple species, such as nascent and mature RNA transcript counts. This has prevented the application of standard likelihood-based statistical methods for analyzing high-throughput, multi-species transcriptomic datasets using biophysical models. Inspired by recent work in machine learning to learn solutions to complex dynamical systems, we leverage neural networks and statistical understanding of system distributions to produce accurate approximations to a steady-state bivariate distribution for a model of the RNA life-cycle that includes nascent and mature molecules. The steady-state distribution to this simple model has no closed-form solution and requires intensive numerical solving techniques: our approach reduces likelihood evaluation time by several orders of magnitude. We demonstrate two approaches, where solutions are approximated by (1) learning the weights of kernel distributions with constrained parameters, or (2) learning both weights and scaling factors for parameters of kernel distributions. We show that our strategies, denoted by kernel weight regression (KWR) and parameter scaled kernel weight regression (psKWR), respectively, enable broad exploration of parameter space and can be used in existing likelihood frameworks to infer transcriptional burst sizes, RNA splicing rates, and mRNA degradation rates from experimental transcriptomic data.

Statement of significanceThe life-cycles of RNA molecules are governed by a set of stochastic events that result in heterogeneous gene expression patterns in genetically identical cells, resulting in the vast diversity of cellular types, responses, and functions. While stochastic models have been used in the field of fluorescence transcriptomics to understand how cells exploit and regulate this inherent randomness, biophysical models have not been widely applied to high-throughput transcriptomic data, as solutions are often intractable and computationally impractical to scale. Our neural approximations of solutions to a two-species transcriptional system enable efficient inference of rates that drive the dynamics of gene expression, thus providing a scalable route to extracting mechanistic information from increasingly available multi-species single-cell transcriptomics data.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Carilli, M. T.</dc:creator>
<dc:creator>Chari, T.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2022-06-16</dc:date>
<dc:identifier>doi:10.1101/2022.06.16.496448</dc:identifier>
<dc:title><![CDATA[Spectral neural approximations for models of transcriptional dynamics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.17.496478v1?rss=1">
<title>
<![CDATA[
Quantitative whole-tissue 3D imaging reveals bacteria in close association with mouse jejunum mucosa 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.17.496478v1?rss=1</link>
<description><![CDATA[
BackgroundThe small intestine (SI) is the primary site of nutrient absorption, so its large surface area lacks the thick protective mucus that is characteristic of the large intestine. Because the SI epithelium is relatively exposed, any microbes that colonize the thin mucosa of the SI may exert a substantial effect on the host. Thus far, potential bacterial colonization of the SI mucosa has only been documented in disease states, suggesting mucosal colonization is a rare occurrence, likely requiring multiple perturbations.

ResultsHere, we tested whether we could induce bacterial association with jejunum mucosa by a combination of malnutrition and oral co-gavage with a specific bacterial cocktail (E. coli and Bacteroides spp.) that has previously induced environmental enteropathy in mouse models. To overcome the current limitations in imaging and allow definite determination of whether bacterial colonization of the SI mucosa is occurring, we optimized our previously developed whole-tissue three-dimensional (3D) imaging tools with third-generation hybridization chain reaction (HCR v3.0) probes. Only in mice that were malnourished and gavaged with the bacterial cocktail did we detect dense bacterial clusters surrounding intestinal villi suggestive of colonization. Healthy mice gavaged with bacteria and malnourished mice not gavaged with bacteria showed no evidence of mucosal colonization. Furthermore, in malnourished mice gavaged with bacteria we detected villus loss, which may represent one possible consequence that bacterial colonization of the SI mucosa has on the host.

ConclusionsOur results suggest that dense bacterial colonization of jejunum mucosa is possible in the presence of multiple perturbations and that villus loss may be one possible consequence to such colonization. Furthermore, our results demonstrate the utility of whole-tissue 3D imaging tools. Although 2D imaging of thin sections may have failed to detect and capture the full spatial complexity of such rare events, whole-tissue 3D imaging tools enabled their detection over large areas of intestinal mucosa and visualization of their spatial complexity in 3D.
]]></description>
<dc:creator>Poceviciute, R.</dc:creator>
<dc:creator>Bogatyrev, S. R.</dc:creator>
<dc:creator>Romano, A. E.</dc:creator>
<dc:creator>Dilmore, A. H.</dc:creator>
<dc:creator>Mondragon-Palomino, O.</dc:creator>
<dc:creator>Takko, H.</dc:creator>
<dc:creator>Ismagilov, R. F.</dc:creator>
<dc:date>2022-06-19</dc:date>
<dc:identifier>doi:10.1101/2022.06.17.496478</dc:identifier>
<dc:title><![CDATA[Quantitative whole-tissue 3D imaging reveals bacteria in close association with mouse jejunum mucosa]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.21.496981v1?rss=1">
<title>
<![CDATA[
Structure of Anabaena flos-aquae gas vesicles revealed by cryo-ET 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.21.496981v1?rss=1</link>
<description><![CDATA[
Gas vesicles (GVs) are gas-filled protein nanostructures employed by several species of bacteria and archaea as flotation devices to enable access to optimal light and nutrients. The unique physical properties of GVs have led to their use as genetically-encodable contrast agents for ultrasound and MRI. Currently, however, the structure and assembly mechanism of GVs remain unknown. Here we employ cryo-electron tomography to reveal how the GV shell is formed by a helical filament of highly conserved GvpA subunits. This filament changes polarity at the center of the GV cylinder--a site that may act as an elongation center. High-resolution subtomogram averaging reveals a corrugated pattern of the shell arising from polymerization of GvpA into a {beta}-sheet. The accessory protein GvpC forms a helical cage around the GvpA shell, providing structural reinforcement. Together, our results help explain the remarkable mechanical properties of GVs and their ability to adopt different diameters and shapes.
]]></description>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Metskas, L. A.</dc:creator>
<dc:creator>Hurt, R. C.</dc:creator>
<dc:creator>Salahshoor, H.</dc:creator>
<dc:creator>Wang, T.-Y.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Lu, G.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2022-06-21</dc:date>
<dc:identifier>doi:10.1101/2022.06.21.496981</dc:identifier>
<dc:title><![CDATA[Structure of Anabaena flos-aquae gas vesicles revealed by cryo-ET]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.21.497102v1?rss=1">
<title>
<![CDATA[
Trajectories for the evolution of bacterial CO2-concentrating mechanisms 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.21.497102v1?rss=1</link>
<description><![CDATA[
Cyanobacteria rely on CO2 concentrating mechanisms (CCMs) that depend on {approx}15 genes to produce two protein complexes: an inorganic carbon (Ci) transporter and a 100+ nm carboxysome compartment that encapsulates rubisco with a carbonic anhydrase (CA) enzyme. Mutations disrupting CCM components prohibit growth in todays atmosphere (0.04% CO2), indicating that CCMs evolved to cope with declining environmental CO2. Indeed, geochemical data and models indicate that atmospheric CO2 has been generally decreasing from high concentrations over the last {approx}3.5 billion years. We used a synthetic reconstitution of a bacterial CCM in E. coli to study the co-evolution of CCMs with atmospheric CO2. We constructed strains expressing putative ancestors of modern CCMs -- strains lacking one or more CCM components -- and evaluated their growth in a variety of CO2 concentrations. Partial forms expressing CA or Ci uptake genes grew better than controls in intermediate CO2 levels ({approx}1%); we observed similar phenotypes in genetic studies of two autotrophic bacteria, H. neapolitanus and C. necator. To explain how partial CCMs improve growth, we advance a model of co-limitation of autotrophic growth by CO2 and HCO3-, as both are required to produce biomass. Our model and results delineated a viable trajectory for bacterial CCM evolution where decreasing atmospheric CO2 induces an HCO3- deficiency that is alleviated by acquisition of CAs or Ci uptake genes, thereby enabling the emergence of a modern CCM. This work underscores the importance of considering physiology and environmental context when studying the evolution of biological complexity.

SignificanceThe greenhouse gas content of the ancient atmosphere is estimated using models and measurements of geochemical proxies. Some inferred high ancient CO2 levels using models of biological CO2 fixation to interpret the C isotopes found in preserved organic matter. Others argued that elevated CO2 could reconcile a faint young Sun with evidence for liquid water on Earth. We took a complementary "synthetic biological" approach to understanding the composition of the ancient atmosphere by studying present-day bacteria engineered to resemble ancient autotrophs. By showing that it is simpler to rationalize the emergence of modern bacterial autotrophs if CO2 was once high, these investigations provided independent evidence for the view that CO2 concentrations were significantly elevated in the atmosphere of early Earth.
]]></description>
<dc:creator>Flamholz, A. I.</dc:creator>
<dc:creator>Dugan, E. J.</dc:creator>
<dc:creator>Panich, J.</dc:creator>
<dc:creator>Desmarais, J. J.</dc:creator>
<dc:creator>Oltrogge, L. M.</dc:creator>
<dc:creator>Fischer, W. W.</dc:creator>
<dc:creator>Singer, S. W.</dc:creator>
<dc:creator>Savage, D. F.</dc:creator>
<dc:date>2022-06-22</dc:date>
<dc:identifier>doi:10.1101/2022.06.21.497102</dc:identifier>
<dc:title><![CDATA[Trajectories for the evolution of bacterial CO2-concentrating mechanisms]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.22.497258v1?rss=1">
<title>
<![CDATA[
Evolution of Carbon Isotope Fractionation in Cyanobacteria 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.22.497258v1?rss=1</link>
<description><![CDATA[
The history of Earths carbon cycle reflects trends in atmospheric composition convolved with the evolution of photosynthesis. Fortunately, key parts of the carbon cycle have been recorded in the carbon isotope ratios of sedimentary rocks. The dominant model used to interpret this record as a proxy for ancient atmospheric CO2 is based on carbon isotope fractionations of modern photoautotrophs, and longstanding questions remain about how their evolution might have impacted the record. We tested the intersection of environment and evolution by measuring both biomass ({varepsilon}p) and enzymatic ({varepsilon}Rubisco) carbon isotope fractionations of a cyanobacterial strain (Synechococcus elongatus PCC 7942) solely expressing a putative ancestral Form 1B rubisco dating to >>1 Ga. This strain, nicknamed ANC, grows in ambient pCO2 and displays larger {varepsilon}p values than WT, despite having a much smaller {varepsilon}Rubisco (17.23 {+/-} 0.61{per thousand} vs. 25.18 {+/-} 0.31{per thousand} respectively). Measuring both enzymatic and biomass fractionation revealed a surprising result--ANC {varepsilon}p exceeded ANC {varepsilon}Rubisco in all conditions tested, contradicting prevailing models of cyanobacterial carbon isotope fractionation. However, these models were corrected by accounting for cyanobacterial physiology, notably the CO2 concentrating mechanism (CCM). Our model suggested that additional fractionating processes like powered inorganic carbon uptake systems contribute to {varepsilon}p, and this effect is exacerbated in ANC. Understanding the evolution of rubisco and the CCM is therefore critical for interpreting the carbon isotope record. Large fluctuations in that record may reflect the evolving efficiency of carbon fixing metabolisms in addition to changes in atmospheric CO2.

Significance StatementEarth scientists rely on chemical fossils like the carbon isotope record to derive ancient atmospheric CO2 concentrations, but interpretation of this record is calibrated using modern organisms. We tested this assumption by measuring the carbon isotope fractionation of a reconstructed ancestral rubisco enzyme (>1 billion years old) in vivo and in vitro. Our results contradicted prevailing models of carbon flow in Cyanobacteria, but our data could be rationalized if light-driven uptake of CO2 is taken into account. Our study showed that the carbon isotope record tracks both the evolution of photosynthesis physiology as well as changes in atmospheric CO2, highlighting the value of considering both evolution and physiology for comparative biological approaches to understanding Earths history.
]]></description>
<dc:creator>Wang, R. Z.</dc:creator>
<dc:creator>Nichols, R. J.</dc:creator>
<dc:creator>Liu, A. K.</dc:creator>
<dc:creator>Flamholz, A. I.</dc:creator>
<dc:creator>Banda, D. M.</dc:creator>
<dc:creator>Savage, D. F.</dc:creator>
<dc:creator>Eiler, J. M.</dc:creator>
<dc:creator>Shih, P. M.</dc:creator>
<dc:creator>Fischer, W. W.</dc:creator>
<dc:date>2022-06-23</dc:date>
<dc:identifier>doi:10.1101/2022.06.22.497258</dc:identifier>
<dc:title><![CDATA[Evolution of Carbon Isotope Fractionation in Cyanobacteria]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.22.497261v1?rss=1">
<title>
<![CDATA[
Identification of orphan ligand-receptor relationships using a cell-based CRISPRa enrichment screening platform. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.22.497261v1?rss=1</link>
<description><![CDATA[
Secreted proteins, which include cytokines, hormones and growth factors, are extracellular ligands that control key signaling pathways mediating cell-cell communication within and between tissues and organs. Many drugs target secreted ligands and their cell-surface receptors. Still, there are hundreds of secreted human proteins that either have no identified receptors ("orphans") and are likely to act through cell surface receptors that have not yet been characterized. Discovery of secreted ligand-receptor interactions by high-throughput screening has been problematic, because the most commonly used high-throughput methods for protein-protein interaction (PPI) screening do not work well for extracellular interactions. Cell-based screening is a promising technology for definition of new ligand-receptor interactions, because multimerized ligands can enrich for cells expressing low affinity cell-surface receptors, and such methods do not require purification of receptor extracellular domains. Here, we present a proteo-genomic cell-based CRISPR activation (CRISPRa) enrichment screening platform employing customized pooled cell surface receptor sgRNA libraries in combination with a magnetic bead selection-based enrichment workflow for rapid, parallel ligand-receptor deorphanization. We curated 80 potentially high value orphan secreted proteins and ultimately screened 20 secreted ligands against two cell sgRNA libraries with targeted expression of all single-pass (TM1) or multi-pass (TM2+) receptors by CRISPRa. We identified previously unknown interactions in 12 of these screens, and validated several of them using surface plasmon resonance and/or cell binding. The newly deorphanized ligands include three receptor tyrosine phosphatase (RPTP) ligands and a chemokine like protein that binds to killer cell inhibitory receptors (KIRs). These new interactions provide a resource for future investigations of interactions between the human secreted and membrane proteomes.
]]></description>
<dc:creator>Siepe, D. H.</dc:creator>
<dc:creator>Henneberg, L. T.</dc:creator>
<dc:creator>Wilson, S. C.</dc:creator>
<dc:creator>Hess, G. T.</dc:creator>
<dc:creator>Bassik, M. C.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:creator>Garcia, K. C.</dc:creator>
<dc:date>2022-06-23</dc:date>
<dc:identifier>doi:10.1101/2022.06.22.497261</dc:identifier>
<dc:title><![CDATA[Identification of orphan ligand-receptor relationships using a cell-based CRISPRa enrichment screening platform.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.27.497663v1?rss=1">
<title>
<![CDATA[
Geometric effects in gas vesicle buckling under ultrasound 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.27.497663v1?rss=1</link>
<description><![CDATA[
Acoustic reporter genes based on gas vesicles (GVs) have enabled the use of ultrasound to noninvasively visualize cellular function in vivo. The specific detection of GV signals relative to background acoustic scattering in tissues is facilitated by nonlinear ultrasound imaging techniques taking advantage of the sonomechanical buckling of GVs. However, the effect of geometry on the buckling behavior of GVs under exposure to ultrasound has not been studied. To understand such geometric effects, we developed computational models of GVs of various lengths and diameters and used finite element simulations to predict their threshold buckling pressures and post-buckling deformations. We demonstrated that the GV diameter has an inverse cubic relation to the threshold buckling pressure, whereas length has no substantial effect. To complement these simulations, we experimentally probed the effect of geometry on the mechanical properties of GVs and the corresponding nonlinear ultrasound signals. The results of these experiments corroborate our computational predictions. This study provides fundamental insights into how geometry affects the sonomechanical properties of GVs, which, in turn, can inform further engineering of these nanostructures for high-contrast, nonlinear ultrasound imaging.

STATEMENT OF SIGNIFICANCEGas vesicles (GVs) are an emerging class of genetically encodable and engineerable imaging agents for ultrasound whose sonomechanical buckling generates nonlinear contrast to enable sensitive and specific imaging in highly scattering biological systems. Though the effect of protein composition on GV buckling has been studied, the effect of geometry has not previously been addressed. This study reveals that geometry, especially GV diameter, significantly alters the threshold acoustic pressures required to induce GV buckling. Our computational predictions and experimental results provide fundamental understanding of the relationship between GV geometry and buckling properties and underscore the utility of GVs for nonlinear ultrasound imaging. Additionally, our results provide suggestions to further engineer GVs to enable in vivo ultrasound imaging with greater sensitivity and higher contrast.
]]></description>
<dc:creator>Salahshoor, H.</dc:creator>
<dc:creator>Yao, Y.</dc:creator>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Nystrom, N. N.</dc:creator>
<dc:creator>Jin, Z.</dc:creator>
<dc:creator>Min, E.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2022-06-29</dc:date>
<dc:identifier>doi:10.1101/2022.06.27.497663</dc:identifier>
<dc:title><![CDATA[Geometric effects in gas vesicle buckling under ultrasound]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.27.497828v1?rss=1">
<title>
<![CDATA[
A prebiotic diet modulates microglial states and motor deficits in α-synuclein overexpressing mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.27.497828v1?rss=1</link>
<description><![CDATA[
Parkinsons disease (PD) is a movement disorder characterized by neuroinflammation, -synuclein pathology, and neurodegeneration. Most cases of PD are non-hereditary, suggesting a strong role for environmental factors, and it has been speculated that disease may originate in peripheral tissues such as the gastrointestinal (GI) tract before affecting the brain. The gut microbiome is altered in PD and may impact motor and GI symptoms as indicated by animal studies, though mechanisms of gut-brain interactions remain incompletely defined. Intestinal bacteria ferment dietary fibers into short-chain fatty acids, with fecal levels of these molecules differing between PD and healthy controls and in mouse models. Among other effects, dietary microbial metabolites can modulate activation of microglia, brain-resident immune cells implicated in PD. We therefore investigated whether a fiber-rich diet influences microglial function in -synuclein overexpressing (ASO) mice, a preclinical model with PD-like symptoms and pathology. Feeding a prebiotic high-fiber diet attenuates motor deficits and reduces -synuclein aggregation in the substantia nigra of mice. Concomitantly, the gut microbiome of ASO mice adopts a profile correlated with health upon prebiotic treatment, which also reduces microglial activation. Single-cell RNA-seq analysis of microglia from the substantia nigra and striatum uncovers increased pro-inflammatory signaling and reduced homeostatic responses in ASO mice compared to wild-type counterparts on standard diets. However, prebiotic feeding reverses pathogenic microglial states in ASO mice and promotes expansion of protective disease-associated macrophage (DAM) subsets of microglia. Notably, depletion of microglia using a CSF1R inhibitor eliminates the beneficial effects of prebiotics by restoring motor deficits to ASO mice despite feeding a prebiotic diet. These studies uncover a novel microglia-dependent interaction between diet and motor symptoms in mice, findings that may have implications for neuroinflammation and PD.
]]></description>
<dc:creator>Abdel-Haq, R.</dc:creator>
<dc:creator>Schlachetzki, J. C. M.</dc:creator>
<dc:creator>Boktor, J. C.</dc:creator>
<dc:creator>Cantu-Jungles, T. M.</dc:creator>
<dc:creator>Thron, T.</dc:creator>
<dc:creator>Zhang, M.</dc:creator>
<dc:creator>Bostick, J. W.</dc:creator>
<dc:creator>Khazaei, T.</dc:creator>
<dc:creator>Chilakala, S.</dc:creator>
<dc:creator>Morais, L. H.</dc:creator>
<dc:creator>Humphrey, G.</dc:creator>
<dc:creator>Keshavarzian, A.</dc:creator>
<dc:creator>Katz, J. E.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Knight, R.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:creator>Hamaker, B. R.</dc:creator>
<dc:creator>Glass, C. K.</dc:creator>
<dc:creator>Mazmanian, S. K.</dc:creator>
<dc:date>2022-06-30</dc:date>
<dc:identifier>doi:10.1101/2022.06.27.497828</dc:identifier>
<dc:title><![CDATA[A prebiotic diet modulates microglial states and motor deficits in α-synuclein overexpressing mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.28.497989v1?rss=1">
<title>
<![CDATA[
Neutralizing monoclonal antibodies elicited by mosaic RBD nanoparticles bind conserved sarbecovirus epitopes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.28.497989v1?rss=1</link>
<description><![CDATA[
Protection from SARS-related coronaviruses with spillover potential and SARS-CoV-2 variants could prevent and/or end pandemics. We show that mice immunized with nanoparticles co-displaying spike receptor-binding domains (RBDs) from eight sarbecoviruses (mosaic-8 RBD-nanoparticles) efficiently elicit cross-reactive anti-sarbecovirus antibodies against conserved class 1/4 and class 3 RBD epitopes. Monoclonal antibodies (mAbs) identified from initial screening of <10,000 single B-cells secreting IgGs binding two or more sarbecovirus RBDs showed cross-reactive binding and neutralization of SARS-CoV-2 variants and animal sarbecoviruses. Single-particle cryo-EM structures of antibody-spike complexes, including a Fab-Omicron complex, mapped neutralizing mAbs to conserved class 1/4 RBD epitopes and revealed neutralization mechanisms, potentials for intra-spike trimer crosslinking by single IgGs, and induced changes in trimer upon Fab binding. In addition, we identified a mAb resembling Bebtelovimab, an EUA-approved human class 3 anti-RBD mAb. These results support using mosaic RBD-nanoparticles to identify therapeutic pan-sarbecovirus and pan-variant mAbs and to elicit them by vaccination.
]]></description>
<dc:creator>Fan, C.</dc:creator>
<dc:creator>Cohen, A. A.</dc:creator>
<dc:creator>Park, M.</dc:creator>
<dc:creator>Hung, A. F.-H.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>Gnanapragasam, P. N.</dc:creator>
<dc:creator>Lee, Y. E.</dc:creator>
<dc:creator>Kakutani, L. M.</dc:creator>
<dc:creator>Wu, Z.</dc:creator>
<dc:creator>Malecek, K. E.</dc:creator>
<dc:creator>Williams, J. C.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2022-06-28</dc:date>
<dc:identifier>doi:10.1101/2022.06.28.497989</dc:identifier>
<dc:title><![CDATA[Neutralizing monoclonal antibodies elicited by mosaic RBD nanoparticles bind conserved sarbecovirus epitopes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.29.498132v1?rss=1">
<title>
<![CDATA[
Integrative single-cell analysis of cardiogenesis identifies developmental trajectories and non-coding mutations in congenital heart disease 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.29.498132v1?rss=1</link>
<description><![CDATA[
Congenital heart defects, the most common birth disorders, are the clinical manifestation of anomalies in fetal heart development - a complex process involving dynamic spatiotemporal coordination among various precursor cell lineages. This complexity underlies the incomplete understanding of the genetic architecture of congenital heart diseases (CHDs). To define the multi-cellular epigenomic and transcriptional landscape of cardiac cellular development, we generated single-cell chromatin accessibility maps of human fetal heart tissues. We identified eight major differentiation trajectories involving primary cardiac cell types, each associated with dynamic transcription factor (TF) activity signatures. We identified similarities and differences of regulatory landscapes of iPSC-derived cardiac cell types and their in vivo counterparts. We interpreted deep learning models that predict cell-type resolved, base-resolution chromatin accessibility profiles from DNA sequence to decipher underlying TF motif lexicons and infer the regulatory impact of non-coding variants. De novo mutations predicted to affect chromatin accessibility in arterial endothelium were enriched in CHD cases versus controls. We used CRISPR-based perturbations to validate an enhancer harboring a nominated regulatory CHD mutation, linking it to effects on the expression of a known CHD gene JARID2. Together, this work defines the cell-type resolved cis-regulatory sequence determinants of heart development and identifies disruption of cell type-specific regulatory elements as a component of the genetic etiology of CHD.
]]></description>
<dc:creator>Ameen, M.</dc:creator>
<dc:creator>Sundaram, L.</dc:creator>
<dc:creator>Banerjee, A.</dc:creator>
<dc:creator>Shen, M.</dc:creator>
<dc:creator>Kundu, S.</dc:creator>
<dc:creator>Nair, S.</dc:creator>
<dc:creator>Shcherbina, A.</dc:creator>
<dc:creator>Gu, M.</dc:creator>
<dc:creator>Wilson, K. D.</dc:creator>
<dc:creator>Varadarajan, A.</dc:creator>
<dc:creator>Vadgama, N.</dc:creator>
<dc:creator>Balsubramani, A.</dc:creator>
<dc:creator>Wu, J. C.</dc:creator>
<dc:creator>Engreitz, J.</dc:creator>
<dc:creator>Farh, K.</dc:creator>
<dc:creator>Karakikes, I.</dc:creator>
<dc:creator>Wang, K. C.</dc:creator>
<dc:creator>Quertermous, T.</dc:creator>
<dc:creator>Greenleaf, W.</dc:creator>
<dc:creator>Kundaje, A.</dc:creator>
<dc:date>2022-06-29</dc:date>
<dc:identifier>doi:10.1101/2022.06.29.498132</dc:identifier>
<dc:title><![CDATA[Integrative single-cell analysis of cardiogenesis identifies developmental trajectories and non-coding mutations in congenital heart disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.07.01.498451v1?rss=1">
<title>
<![CDATA[
Competing constraints shape the non-equilibrium limits of cellular decision making 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.07.01.498451v1?rss=1</link>
<description><![CDATA[
Gene regulation is central to cellular function. Yet, despite decades of work, we lack quantitative models that can predict how transcriptional control emerges from molecular interactions at the gene locus. Thermodynamic models of transcription, which assume that gene circuits operate at equilibrium, have previously been employed with considerable success in the context of bacterial systems. However, the presence of ATP-dependent processes within the eukaryotic transcriptional cycle suggests that equilibrium models may be insufficient to capture how eukaryotic gene circuits sense and respond to input transcription factor concentrations. Here, we employ simple kinetic models of transcription to investigate how energy dissipation within the transcriptional cycle impacts the rate at which genes transmit information and drive cellular decisions. We find that biologically plausible levels of energy input can lead to significant gains in how rapidly gene loci transmit information, but discover that the regulatory mechanisms underlying these gains change depending on the level of interference from non-cognate activator binding. When interference is low, information is maximized by harnessing energy to push the sensitivity of the transcriptional response to input transcription factors beyond its equilibrium limits. Conversely, when interference is high, conditions favor genes that harness energy to increase transcriptional specificity by proofreading activator identity. Our analysis further reveals that equilibrium gene regulatory mechanisms break down as transcriptional interference increases, suggesting that energy dissipation may be indispensable in systems where non-cognate factor interference is sufficiently large.
]]></description>
<dc:creator>Lammers, N. C.</dc:creator>
<dc:creator>Flamholz, A.</dc:creator>
<dc:creator>Garcia, H. G.</dc:creator>
<dc:date>2022-07-03</dc:date>
<dc:identifier>doi:10.1101/2022.07.01.498451</dc:identifier>
<dc:title><![CDATA[Competing constraints shape the non-equilibrium limits of cellular decision making]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.07.04.498658v1?rss=1">
<title>
<![CDATA[
Evolutionary Diversification of Methanotrophic Ca. Methanophagales (ANME-1) and Their Expansive Virome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.07.04.498658v1?rss=1</link>
<description><![CDATA[
Candidatus Methanophagales (ANME-1) is a major order-level clade of archaea responsible for methane removal in deep-sea sediments through the anaerobic oxidation of methane. Yet the extent of their diversity and factors which drive their dynamics and evolution remain poorly understood. Here, by sampling hydrothermal rocks and sediments, we expand their phylogenetic diversity and characterize a new deep-branching, thermophilic ANME-1 family,  Candidatus Methanospirareceae (ANME-1c). They are phylogenetically closest to the short-chain-alkane oxidizers  Candidatus Syntrophoarchaeales and  Candidatus Alkanophagales, and encode ancestral features including a methyl coenzyme M reductase chaperone McrD and a hydrogenase complex. Global phylogeny and near-complete genomes clarified that the debated hydrogen metabolism within ANME-1 is an ancient trait that was vertically inherited but differentially lost during lineage diversification. Our expanded genomic and metagenomic sampling allowed the discovery of viruses constituting 3 new orders and 16 new families that so far are exclusive to ANME-1 hosts. These viruses represent 4 major archaeal virus assemblages, characterized by tailless icosahedral, head-tailed, rod-shaped, and spindle-shaped virions, but display unique structural and replicative signatures. Exemplified by the analyses of thymidylate synthases that unveiled a virus-mediated ancestral process of host gene displacement, this expansive ANME-1 virome carries a large gene repertoire that can influence their hosts across different timescales. Our study thus puts forth an emerging evolutionary continuum between anaerobic methane and short-chain-alkane oxidizers and opens doors for exploring the impacts of viruses on the dynamics and evolution of the anaerobic methane-driven ecosystems.
]]></description>
<dc:creator>Laso-Perez, R.</dc:creator>
<dc:creator>Wu, F.</dc:creator>
<dc:creator>Cremiere, A.</dc:creator>
<dc:creator>Speth, D. R.</dc:creator>
<dc:creator>Magyar, J. S.</dc:creator>
<dc:creator>Krupovic, M.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2022-07-04</dc:date>
<dc:identifier>doi:10.1101/2022.07.04.498658</dc:identifier>
<dc:title><![CDATA[Evolutionary Diversification of Methanotrophic Ca. Methanophagales (ANME-1) and Their Expansive Virome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.07.10.499405v1?rss=1">
<title>
<![CDATA[
A synthetic protein-level neural network in mammalian cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.07.10.499405v1?rss=1</link>
<description><![CDATA[
Artificial neural networks provide a powerful paradigm for information processing that has transformed diverse fields. Within living cells, genetically encoded synthetic molecular networks could, in principle, harness principles of neural computation to classify molecular signals. Here, we combine de novo designed protein heterodimers and engineered viral proteases to implement a synthetic protein circuit that performs winner-take-all neural network computation. This "perceptein" circuit includes modules that compute weighted sums of input protein concentrations through reversible binding interactions, and allow for self-activation and mutual inhibition of protein components using irreversible proteolytic cleavage reactions. Altogether, these interactions comprise a network of 310 chemical reactions stemming from 8 expressed protein species. The complete system achieves signal classification with tunable decision boundaries in mammalian cells. These results demonstrate how engineered protein-based networks can enable programmable signal classification in living cells.

One-Sentence SummaryA synthetic protein circuit that performs winner-take-all neural network computation in mammalian cells
]]></description>
<dc:creator>Chen, Z.</dc:creator>
<dc:creator>Linton, J. M.</dc:creator>
<dc:creator>Zhu, R.</dc:creator>
<dc:creator>Elowitz, M.</dc:creator>
<dc:date>2022-07-11</dc:date>
<dc:identifier>doi:10.1101/2022.07.10.499405</dc:identifier>
<dc:title><![CDATA[A synthetic protein-level neural network in mammalian cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.07.12.499653v1?rss=1">
<title>
<![CDATA[
Identification of a distinct ductal subpopulation with self-renewal and differentiation potential from the adult murine pancreas 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.07.12.499653v1?rss=1</link>
<description><![CDATA[
Pancreatic ducts function to deliver digestive enzymes into the intestines. Upon injury, ducts can become proliferative and contribute to tissue regeneration; however, the identity of the ductal cells that contribute to these processes is unknown. We combined fluorescence-activated cell sorting, a methylcellulose-containing 3-dimensional culture, droplet RNA-sequencing, and a clonal lineage tracing tool to identify and isolate a distinct subpopulation of pancreatic ductal cells that exhibit progenitor cell properties. These ductal cells are unique in that they form tightly-bound clusters (termed FSCmid-high), with an average of 8 cells per cluster. FSCmid-high clusters comprise only about 0.1% of the total pancreas, are tri-potent for duct, acinar and endocrine lineages, and self-renew robustly in vitro. Transcriptomic analysis of FSCmid-high clusters reveals enrichment for genes involved in cell-cell interactions, organ development, and cancer pathways. FSCmid-high clusters express embryonic pancreatic progenitor markers Sox9, Pdx1, and Nkx6-1 at both transcription and protein levels. FSCmid-high clusters are resistant to enzymatic dissociation and survive severe in vivo acinar injury, which induces formation of ductal rosettes that become proliferative within 14 days. Thus, FSCmid-high clusters represent a small subset of ductal cells with progenitor cell properties. These rare progenitor-like duct cell clusters have implications in pancreas regeneration and tumor initiation/progression.
]]></description>
<dc:creator>Tremblay, J. R.</dc:creator>
<dc:creator>Ortiz, J. A.</dc:creator>
<dc:creator>Quijano, J. C.</dc:creator>
<dc:creator>Zook, H.</dc:creator>
<dc:creator>LeBon, J. M.</dc:creator>
<dc:creator>Li, W.</dc:creator>
<dc:creator>Jou, K.</dc:creator>
<dc:creator>Tsark, W.</dc:creator>
<dc:creator>Mann, J. R.</dc:creator>
<dc:creator>Kozlowski, M.</dc:creator>
<dc:creator>Tirrell, D. A.</dc:creator>
<dc:creator>Esni, F.</dc:creator>
<dc:creator>Engle, D. D.</dc:creator>
<dc:creator>Riggs, A. D.</dc:creator>
<dc:creator>Ku, H. T.</dc:creator>
<dc:date>2022-07-13</dc:date>
<dc:identifier>doi:10.1101/2022.07.12.499653</dc:identifier>
<dc:title><![CDATA[Identification of a distinct ductal subpopulation with self-renewal and differentiation potential from the adult murine pancreas]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.07.14.499766v1?rss=1">
<title>
<![CDATA[
Fate Bias and Transcriptional Memory of human B cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.07.14.499766v1?rss=1</link>
<description><![CDATA[
Lineage tracking offers a direct approach to study cell fate determination. In this work we combined single cell transcriptomics and lineage tracing to better understand fate-choice in human B cells. Using the antibody sequence to trace cell lineage during in vitro differentiation, we identified intrinsic proliferative and cell fate biases of B cell subtypes. Clonal analysis revealed that IgM memory B cells were more proliferative than any other B cell subtype, and that cells from the same clone had highly concordant fates. We found that transcriptional memory within clones varies across genes, with strongest persistence in genes related to cell fate determination. Similar persistent transcriptional programs were observed in human plasma cells from bone marrow, suggesting that these programs maintain long-term cell fate in vivo. These results show that cell-intrinsic fate bias influences human B cell differentiation and reveal molecular programs underpinning cell fate determination in B cells.
]]></description>
<dc:creator>Swift, M.</dc:creator>
<dc:creator>Horns, F.</dc:creator>
<dc:creator>Quake, S.</dc:creator>
<dc:date>2022-07-15</dc:date>
<dc:identifier>doi:10.1101/2022.07.14.499766</dc:identifier>
<dc:title><![CDATA[Fate Bias and Transcriptional Memory of human B cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.07.20.500694v1?rss=1">
<title>
<![CDATA[
Integrated multi-cohort analysis of the Parkinson's disease gut metagenome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.07.20.500694v1?rss=1</link>
<description><![CDATA[
BackgroundThe gut microbiome is altered in several neurologic disorders including Parkinsons disease (PD).

ObjectivesProfile the fecal gut metagenome in PD for alterations in microbial composition, taxon abundance, metabolic pathways, and microbial gene products, and their relationship with disease progression.

MethodsShotgun metagenomic sequencing was conducted on 244 stool donors from two independent cohorts in the United States, including individuals with PD (n=48, n=47, respectively), environmental Household Controls (HC, n=29, n=30), and community Population Controls (PC, n=41, n=49). Microbial features consistently altered in PD compared to HC and PC subjects were identified. Data were cross-referenced to public metagenomic datasets from two previous studies in Germany and China to determine generalizable microbiome features.

ResultsThe gut microbiome in PD shows significant alterations in community composition. Robust taxonomic alterations include depletion of putative "beneficial" gut commensals Faecalibacterium prausnitzii and Eubacterium and Roseburia species, and increased abundance of Akkermansia muciniphila and Bifidobacterium species. Pathway enrichment analysis and metabolic potential, constructed from microbial gene abundance, revealed disruptions in microbial carbohydrate and lipid metabolism and increased amino acid and nucleotide metabolism. These global gene-level signatures indicate an increased response to oxidative stress, decreased cellular growth and microbial motility, and disrupted inter-community signaling.

ConclusionsA metagenomic meta-analysis of PD shows consistent and novel alterations in taxonomic representation, functional metabolic potential, and microbial gene abundance across four independent studies from three continents. These data reveal stereotypic changes in the gut microbiome are a consistent feature of PD, highlighting potential diagnostic and therapeutic avenues for future research.
]]></description>
<dc:creator>Boktor, J. C.</dc:creator>
<dc:creator>Sharon, G.</dc:creator>
<dc:creator>Verhagen Metman, L. A.</dc:creator>
<dc:creator>Hall, D. A.</dc:creator>
<dc:creator>Engen, P. A.</dc:creator>
<dc:creator>Zreloff, Z.</dc:creator>
<dc:creator>Hakim, D. J.</dc:creator>
<dc:creator>Bostick, J. W.</dc:creator>
<dc:creator>Ousey, J.</dc:creator>
<dc:creator>Lange, D.</dc:creator>
<dc:creator>Humphrey, G.</dc:creator>
<dc:creator>Ackermann, G.</dc:creator>
<dc:creator>Carlin, M.</dc:creator>
<dc:creator>Knight, R.</dc:creator>
<dc:creator>Keshavarzian, A.</dc:creator>
<dc:creator>Mazmanian, S. K.</dc:creator>
<dc:date>2022-07-21</dc:date>
<dc:identifier>doi:10.1101/2022.07.20.500694</dc:identifier>
<dc:title><![CDATA[Integrated multi-cohort analysis of the Parkinson's disease gut metagenome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.07.21.500524v1?rss=1">
<title>
<![CDATA[
Single-nucleus resolution mapping of the adult C. elegans and its application to elucidate inter- and trans-generational response to alcohol. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.07.21.500524v1?rss=1</link>
<description><![CDATA[
Single-cell RNA transcriptomic platforms have significantly contributed to our understanding of tissue heterogeneity as well as of developmental and cellular differentiation trajectories. They also provide an opportunity to map an organisms response to environmental cues with high resolution and unbiasedly identify the cell types that are the most transcriptionally sensitive to exposures. Here, we applied single nucleus RNA-seq experimental and computational approaches to C. elegans to establish the transcriptome of the adult nematode and comprehensively characterize the transcriptional impact of ethanol as a model environmental exposure on the entire organism at cell type-resolution over several generations. Clustering, tissue and phenotype enrichment, and gene ontology analyses identified 31 clusters representing a diverse number of adult cell types, including those from syncytial and multi-nucleated tissues which are difficult to assess by single cell RNA-seq, such as the mitotic and meiotic germline, hypodermal cells, and the intestine. We applied this method to identify the impact of inter- and trans-generational exposure to two human-relevant doses of alcohol. Cell type proportions were not significantly altered by ethanol. However, Euclidean distance analysis identified several germline, striated muscle, and neuronal clusters as being major transcriptional targets of ethanol at both the F1 and F3 generations although the relative order of clusters changed between generations. The impact on germline clusters was further confirmed by phenotypic enrichment analysis as well as functional validation, namely a remarkable inter- and trans-generational increase in germline apoptosis, aneuploidy, and embryonic lethality. Together, snRNA-seq of the adult C. elegans represents a powerful approach for the detailed examination of an adult organisms response to environmental cues.
]]></description>
<dc:creator>Truong, L.</dc:creator>
<dc:creator>CHEN, Y.-W.</dc:creator>
<dc:creator>Barrere-Cain, R.</dc:creator>
<dc:creator>Shuck, K.</dc:creator>
<dc:creator>Xiao, W.</dc:creator>
<dc:creator>Levenson, M. T.</dc:creator>
<dc:creator>da Veiga Beltrame, E.</dc:creator>
<dc:creator>Panter, B.</dc:creator>
<dc:creator>Reich, E.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Yang, X.</dc:creator>
<dc:creator>Allard, P.</dc:creator>
<dc:date>2022-07-22</dc:date>
<dc:identifier>doi:10.1101/2022.07.21.500524</dc:identifier>
<dc:title><![CDATA[Single-nucleus resolution mapping of the adult C. elegans and its application to elucidate inter- and trans-generational response to alcohol.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.07.21.500558v1?rss=1">
<title>
<![CDATA[
Symbiosis-driven development in an early branching metazoan 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.07.21.500558v1?rss=1</link>
<description><![CDATA[
Microbes can initiate developmental gene regulatory cascades in animals. The molecular mechanisms underlying microbe-induced animal development and the evolutionary steps to integrate microbial signals into regulatory programs remain poorly understood. In the upside-down jellyfish Cassiopea xamachana, a dinoflagellate endosymbiont initiates the life stage transition from the sessile polyp to the sexual medusa. We found that metabolic products derived from symbiont carotenoids may be important to initiate C. xamachana development, in addition to expression of conserved genes involved in medusa development of non-symbiotic jellyfish. We also revealed the transcription factor COUP is expressed during metamorphosis, potentially as a co-regulator of nuclear receptor RXR. These data suggest relatively few steps may be necessary to integrate symbiont signals into gene regulatory networks and cements the role of the symbiont as a key trigger for life history transition in C. xamachana.
]]></description>
<dc:creator>Ohdera, A. H.</dc:creator>
<dc:creator>Darymple, J.</dc:creator>
<dc:creator>Avila-Magana, V.</dc:creator>
<dc:creator>Sharp, V.</dc:creator>
<dc:creator>Watson, K.</dc:creator>
<dc:creator>McCauley, M.</dc:creator>
<dc:creator>Steinworth, B.</dc:creator>
<dc:creator>Diaz-Almeyda, E. M.</dc:creator>
<dc:creator>Kitchen, S. A.</dc:creator>
<dc:creator>Poole, A. Z.</dc:creator>
<dc:creator>Bellantuono, A. J.</dc:creator>
<dc:creator>Haridas, S.</dc:creator>
<dc:creator>Grigoriev, I. V.</dc:creator>
<dc:creator>Goentoro, L.</dc:creator>
<dc:creator>Vallen, E.</dc:creator>
<dc:creator>Baker, D. M.</dc:creator>
<dc:creator>LaJeunesse, T. C.</dc:creator>
<dc:creator>Loesgen, S.</dc:creator>
<dc:creator>martindale, m. q.</dc:creator>
<dc:creator>DeGennaro, M.</dc:creator>
<dc:creator>Fitt, W. K.</dc:creator>
<dc:creator>Medina, M.</dc:creator>
<dc:date>2022-07-22</dc:date>
<dc:identifier>doi:10.1101/2022.07.21.500558</dc:identifier>
<dc:title><![CDATA[Symbiosis-driven development in an early branching metazoan]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.07.26.501648v1?rss=1">
<title>
<![CDATA[
Modulation of bacterial cell size and growth rate via activation of a cell envelope stress response 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.07.26.501648v1?rss=1</link>
<description><![CDATA[
Fluctuating conditions and diverse stresses are typical in natural environments. In response, cells mount complex responses across multiple scales, including adjusting their shape to withstand stress. In enterobacteria, the Rcs phosphorelay is activated by cell envelope damage and by changes to periplasmic dimensions and cell width. Here, we investigated the physiological and morphological consequences of Rcs activation in Escherichia coli in the absence of stresses, using an inducible version of RcsF that mislocalizes to the inner membrane, RcsFIM. Expression of RcsFIM immediately reduced cellular growth rate and the added length per cell cycle in a manner that was directly dependent on induction levels, but independent of Rcs-induced capsule production. At the same time, cells increased intracellular concentration of the cell division protein FtsZ, and decreased the distance between division rings in filamentous cells. Depletion of the Rcs negative regulator IgaA phenocopied RcsFIM induction, indicating that IgaA is essential due to growth inhibition in its absence. However, A22 treatment did not affect growth rate or FtsZ intracellular concentration, despite activating the Rcs system. These findings suggest that the effect of Rcs activation on FtsZ levels is mediated indirectly through growth-rate changes, and highlight feedbacks among the Rcs stress response, growth dynamics, and cell-size control.
]]></description>
<dc:creator>Miguel, A.</dc:creator>
<dc:creator>Zietek, M.</dc:creator>
<dc:creator>Shi, H.</dc:creator>
<dc:creator>Sueki, A.</dc:creator>
<dc:creator>Maier, L.</dc:creator>
<dc:creator>Verheul, J.</dc:creator>
<dc:creator>den Blaauwen, T.</dc:creator>
<dc:creator>Van Valen, D. A.</dc:creator>
<dc:creator>Typas, A.</dc:creator>
<dc:creator>Huang, K. C.</dc:creator>
<dc:date>2022-07-27</dc:date>
<dc:identifier>doi:10.1101/2022.07.26.501648</dc:identifier>
<dc:title><![CDATA[Modulation of bacterial cell size and growth rate via activation of a cell envelope stress response]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.07.27.501785v1?rss=1">
<title>
<![CDATA[
Antibody recognition of CD4-induced open HIV-1 Env trimers 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.07.27.501785v1?rss=1</link>
<description><![CDATA[
HIV-1 envelope (Env), a heterotrimer of gp120-gp41 subunits, mediates fusion of the viral and host cell membranes after interactions with the host receptor CD4 and a coreceptor. CD4 binding induces rearrangements in Env trimer, resulting in a CD4-induced (CD4i) open Env conformation. Structural studies of antibodies isolated from infected donors have defined antibody-Env interactions, with one class of antibodies specifically recognizing the CD4i open Env conformation. Here, we characterize a group of monoclonal antibodies isolated from HIV-1 infected donors (V2i mAbs) that display characteristics of CD4i antibodies. Binding experiments demonstrate that the V2i mAbs preferentially recognize CD4-bound open Env trimers. Structural characterizations of V2i mAb-Env-CD4 trimer complexes using single-particle cryo-electron microscopy show recognition by V2i mAbs using different angles of approach to the gp120 V1V2 domain and the {beta}2/{beta}3 strands on a CD4i open conformation Env with no direct interactions of the mAbs with CD4. We also characterize CG10, a CD4i antibody that was raised in mice immunized with a gp120-CD4 complex, complexed with Env trimer and CD4. CG10 exhibits similar characteristics to the V2i antibodies: i.e., recognition of the open Env conformation, but shows direct contacts to both CD4 and gp120. Structural comparisons of these and previously characterized CD4i antibody interactions with Env provide a suggested mechanism for how these antibodies are elicited during HIV-1 infection.

ImportanceThe RV144 HIV-1 clinical vaccination trial showed mild protection against viral infection. Antibody responses to the V1V2 region of HIV-1 Env gp120 were correlated inversely with the risk of infection. In addition, antibodies targeting V1V2 have been correlated with protections from SIV and SHIV infections in non-human primates. We structurally characterized V2i antibodies directed against V1V2 isolated from HIV-1 infected humans in complex with open Env trimers bound to the host receptor CD4. We also characterized a CD4i antibody that interacts with CD4 as well as the gp120 subunit of an open Env trimer. Our study suggests how V2i and CD4i antibodies were elicited during HIV-1 infection.
]]></description>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Dam, K.-M. A.</dc:creator>
<dc:creator>Gershoni, J. M.</dc:creator>
<dc:creator>Zolla-Pazner, S.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2022-07-28</dc:date>
<dc:identifier>doi:10.1101/2022.07.27.501785</dc:identifier>
<dc:title><![CDATA[Antibody recognition of CD4-induced open HIV-1 Env trimers]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.01.502371v1?rss=1">
<title>
<![CDATA[
Mouse-embryo model derived exclusively from embryonic stem cells undergo neurulation and heart development 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.01.502371v1?rss=1</link>
<description><![CDATA[
Several in vitro models have been developed to recapitulate mouse embryogenesis solely from embryonic stem cells (ESCs). Despite mimicking many aspects of early development, they fail to capture the interactions between embryonic and extraembryonic tissues. To overcome this difficulty, we have developed a mouse ESC-based in vitro model that reconstitutes the pluripotent ESC lineage and the two extra-embryonic lineages of the post-implantation embryo by transcription factor-mediated induction. This unified model recapitulates developmental events from embryonic day 5.5 to 8.5, including gastrulation, and formation of the anterior-posterior axis, brain, a beating heart structure, and the development of extraembryonic tissues, including yolk sac and chorion. Comparing single-cell RNA sequencing from individual structures with time-matched natural embryos identified remarkably similar transcriptional programs across lineages, but also showed when and where the model diverges from the natural program. Our findings demonstrate an extra-ordinary plasticity of ESCs to self-organize and generate a whole embryo-like structure.
]]></description>
<dc:creator>Lau, K. Y. C.</dc:creator>
<dc:creator>Rubinstein, H.</dc:creator>
<dc:creator>Gantner, C. W.</dc:creator>
<dc:creator>Amadei, G.</dc:creator>
<dc:creator>Stelzer, Y.</dc:creator>
<dc:creator>Zernicka-Goetz, M.</dc:creator>
<dc:date>2022-08-02</dc:date>
<dc:identifier>doi:10.1101/2022.08.01.502371</dc:identifier>
<dc:title><![CDATA[Mouse-embryo model derived exclusively from embryonic stem cells undergo neurulation and heart development]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.01.502375v1?rss=1">
<title>
<![CDATA[
Stem cell-derived mouse embryos develop within an extra-embryonic yolk sac to form anterior brain regions and a beating heart 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.01.502375v1?rss=1</link>
<description><![CDATA[
Embryo-like structures generated from stem cells can achieve varying developmental milestones, but none have been shown to progress through gastrulation, neurulation, and organogenesis.1-7 Here, we show that "ETiX" mouse embryos, established from embryonic stem cells aggregated with trophoblast stem cells and inducible extraembryonic endoderm stem cells, can develop through gastrulation and beyond to undertake neural induction and generate the progenitors needed to create the entire organism. The head-folds of ETiX embryos show anterior expression of Otx2, defining forebrain and midbrain regions that resemble those of the natural mouse embryo. ETiX embryos also develop beating hearts, trunk structures comprising a neural tube and somites, tail buds containing neuromesodermal progenitors and primordial germ cells, and gut tubes derived from definitive endoderm. A fraction of ETiX embryos show neural tube abnormalities, which can be partially rescued by treatment with the metabolically active form of folic acid, reminiscent of common birth defects and therapies in humans. Notably, ETiX embryos also develop a yolk sac with blood islands. Overall, ETiX embryos uniquely recapitulate natural embryos, developing further than any other stem-cell derived model, through multiple post-implantation stages and within extra-embryonic membranes.
]]></description>
<dc:creator>Zernicka-Goetz, M.</dc:creator>
<dc:creator>Amadei, G.</dc:creator>
<dc:creator>Handford, C. E.</dc:creator>
<dc:creator>De Jonghe, J.</dc:creator>
<dc:creator>Hollfelder, F.</dc:creator>
<dc:creator>Glover, D.</dc:creator>
<dc:date>2022-08-02</dc:date>
<dc:identifier>doi:10.1101/2022.08.01.502375</dc:identifier>
<dc:title><![CDATA[Stem cell-derived mouse embryos develop within an extra-embryonic yolk sac to form anterior brain regions and a beating heart]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.08.503264v1?rss=1">
<title>
<![CDATA[
Optical O2 sensors also respond to redox active molecules commonly secreted by bacteria 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.08.503264v1?rss=1</link>
<description><![CDATA[
From a metabolic perspective, molecular oxygen (O2) is arguably the most significant constituent of Earths atmosphere. Nearly every facet of microbial physiology is sensitive to the presence and concentration of O2, which is the most favorable terminal electron acceptor used by biological organisms and also a dangerously reactive oxidant. As O2 has such sweeping implications for physiology, researchers have developed diverse approaches to measure O2 concentrations in natural and laboratory settings. Recent improvements to phosphorescent O2 sensors piqued our interest due to the promise of optical measurement of spatiotemporal O2 dynamics. However, we found that our preferred bacterial model, Pseudomonas aeruginosa PA14, secretes more than one molecule that quenches such sensors, complicating O2 measurements in PA14 cultures and biofilms. Assaying supernatants from cultures of 9 bacterial species demonstrated that this phenotype is common: all supernatants quenched a soluble O2 probe substantially. Phosphorescent O2 probes are often embedded in solid support for protection, but an embedded probe called O2NS was quenched by most supernatants as well. Measurements using pure compounds indicated that quenching is due to interactions with redox-active small molecules including phenazines and flavins. Uncharged and weakly-polar molecules like pyocyanin were especially potent quenchers of O2NS. These findings underscore that optical O2 measurements made in the presence of bacteria should be carefully controlled to ensure that O2, and not bacterial secretions, is measured, and motivate the design of custom O2 probes for specific organisms to circumvent sensitivity to redox-active metabolites.

ImportanceWhen they are closely-packed, as in biofilms, colonies, and soils, microbes can consume O2 faster than it diffuses. As such, O2 concentrations in natural environments can vary greatly over time and space, even on the micrometer scale. Wetting soil, for example, slows O2 diffusion higher in the soil column, which, in concert with microbial respiration, greatly diminishes [O2] at depth. Given that variation in [O2] has outsized implications for microbial physiology, there is great interest in measuring the dynamics of [O2] in microbial cultures and biofilms. We demonstrate that certain classes of bacterial metabolites frustrate optical measurement of [O2] with phosphorescent sensors, but also that some species (e.g. E. coli) do not produce problematic secretions under the conditions tested. Our work therefore offers a strategy for identifying organisms and culture conditions in which optical quantification of spatiotemporal [O2] dynamics with current sensors is feasible.
]]></description>
<dc:creator>Flamholz, A. I.</dc:creator>
<dc:creator>Saccomano, S.</dc:creator>
<dc:creator>Cash, K. J.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2022-08-09</dc:date>
<dc:identifier>doi:10.1101/2022.08.08.503264</dc:identifier>
<dc:title><![CDATA[Optical O2 sensors also respond to redox active molecules commonly secreted by bacteria]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.09.502705v1?rss=1">
<title>
<![CDATA[
Selective Serotonin Reuptake Inhibitors Within Cells: Temporal Resolution in Cytoplasm, Endoplasmic Reticulum, and Membrane 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.09.502705v1?rss=1</link>
<description><![CDATA[
Selective serotonin reuptake inhibitors (SSRIs) are the most prescribed treatment for individuals experiencing major depressive disorder (MDD). The therapeutic mechanisms that take place before, during, or after SSRIs bind the serotonin transporter (SERT) are poorly understood, partially because no studies exist of the cellular and subcellular pharmacokinetic properties of SSRIs in living cells. We studied escitalopram and fluoxetine using new intensity- based drug-sensing fluorescent reporters ("iDrugSnFRs") targeted to the plasma membrane (PM), cytoplasm, or endoplasmic reticulum (ER) of cultured neurons and mammalian cell lines. We also employed chemical detection of drug within cells and phospholipid membranes. The drugs attain equilibrium in neuronal cytoplasm and ER, at approximately the same concentration as the externally applied solution, with time constants of a few s (escitalopram) or 200-300 s (fluoxetine). Simultaneously, the drugs accumulate within lipid membranes by [&ge;] 18-fold (escitalopram) or 180-fold (fluoxetine), and possibly by much larger factors. Both drugs leave cytoplasm, lumen, and membranes just as quickly during washout. We synthesized membrane-impermeant quaternary amine derivatives of the two SSRIs. The quaternary derivatives are substantially excluded from membrane, cytoplasm, and ER for > 2.4 h. They inhibit SERT transport-associated currents 6- or 11-fold less potently than the SSRIs (escitalopram or fluoxetine derivative, respectively), providing useful probes for distinguishing compartmentalized SSRI effects. Although our measurements are orders of magnitude faster than the "therapeutic lag" of SSRIs, these data suggest that SSRI-SERT interactions within organelles or membranes may play roles during either the therapeutic effects or the "antidepressant discontinuation syndrome".

SIGNIFICANCE STATEMENTSelective serotonin reuptake inhibitors stabilize mood in several disorders. In general, these drugs bind to the serotonin (5-hydroxytryptamine) transporter (SERT), which clears serotonin from CNS and peripheral tissues. SERT ligands are effective and relatively safe; primary care practitioners often prescribe them. However, they have several side effects and require 2 to 6 weeks of continuous administration until they act effectively. How they work remains perplexing, contrasting with earlier assumptions that the therapeutic mechanism involves SERT inhibition followed by increased extracellular serotonin levels. This study establishes that two SERT ligands, fluoxetine and escitalopram, enter neurons within minutes, while simultaneously accumulating in many membranes. Such knowledge will motivate future research, hopefully revealing where and how SERT ligands "engage" their therapeutic target(s).
]]></description>
<dc:creator>Nichols, A. L.</dc:creator>
<dc:creator>Blumenfeld, Z.</dc:creator>
<dc:creator>Luebbert, L.</dc:creator>
<dc:creator>Knox, H. J.</dc:creator>
<dc:creator>Muthusamy, A. K.</dc:creator>
<dc:creator>Marvin, J. S.</dc:creator>
<dc:creator>Kim, C. H.</dc:creator>
<dc:creator>Grant, S. N.</dc:creator>
<dc:creator>Walton, D. P.</dc:creator>
<dc:creator>Cohen, B. N.</dc:creator>
<dc:creator>Hammar, R.</dc:creator>
<dc:creator>Looger, L. L.</dc:creator>
<dc:creator>Artursson, P.</dc:creator>
<dc:creator>Dougherty, D. A.</dc:creator>
<dc:creator>Lester, H. A.</dc:creator>
<dc:date>2022-08-12</dc:date>
<dc:identifier>doi:10.1101/2022.08.09.502705</dc:identifier>
<dc:title><![CDATA[Selective Serotonin Reuptake Inhibitors Within Cells: Temporal Resolution in Cytoplasm, Endoplasmic Reticulum, and Membrane]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.11.503677v1?rss=1">
<title>
<![CDATA[
Remote sensing-based forest modeling reveals positive effects of functional diversity on productivity at local spatial scale 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.11.503677v1?rss=1</link>
<description><![CDATA[
O_LIForest biodiversity is critical for many ecosystem functions and services at plot scale, but it is uncertain how biodiversity influences ecosystem functioning across environmental gradients and contiguous larger areas. We used remote sensing and process-based terrestrial biosphere modeling to explore functional diversity-productivity relationships at multiple scales for a heterogeneous forest site in Switzerland.
C_LIO_LIWe ran the biosphere model with empirical data about forest structure and composition derived from ground-based surveys, airborne laser scanning and imaging spectroscopy for the years 2006-2015 at 10x10-m spatial resolution. We then related the model outputs forest productivity to functional diversity under observed and experimental model conditions.
C_LIO_LIFunctional diversity increased productivity significantly (p < 0.001) across all simulations at 20x20-m to 30x30-m scale, but at 100x100-m scale positive relationships disappeared under homogeneous soil conditions.
C_LIO_LIWhereas local functional diversity was an important driver of productivity, environmental context (especially soil depth, texture and water availability) underpinned the variation of productivity (and functional diversity) at larger spatial scales. Integration of remotely-sensed information on canopy composition and structure into terrestrial biosphere models helps fill the knowledge gap about how plant biodiversity affects carbon cycling and biosphere feedbacks onto climate over large contiguous areas.
C_LI
]]></description>
<dc:creator>Schneider, F. D.</dc:creator>
<dc:creator>Longo, M.</dc:creator>
<dc:creator>Paul-Limoges, E.</dc:creator>
<dc:creator>Scholl, V. M.</dc:creator>
<dc:creator>Schmid, B.</dc:creator>
<dc:creator>Morsdorf, F.</dc:creator>
<dc:creator>Pavlick, R. P.</dc:creator>
<dc:creator>Schimel, D. S.</dc:creator>
<dc:creator>Schaepman, M. E.</dc:creator>
<dc:creator>Moorcroft, P. R.</dc:creator>
<dc:date>2022-08-15</dc:date>
<dc:identifier>doi:10.1101/2022.08.11.503677</dc:identifier>
<dc:title><![CDATA[Remote sensing-based forest modeling reveals positive effects of functional diversity on productivity at local spatial scale]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.15.504007v1?rss=1">
<title>
<![CDATA[
Pervasive SUMOylation of heterochromatin and piRNA pathway proteins 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.15.504007v1?rss=1</link>
<description><![CDATA[
Genome regulation involves complex and highly regulated protein interactions that are often mediated through post-translational modifications (PTMs). SUMOylation - the covalent attachment of the small ubiquitin-like modifier (SUMO) - is a conserved PTM in eukaryotes that has been implicated in a number of essential processes such as nuclear import, DNA damage repair, transcriptional control, and chromatin organization. In Drosophila, SUMO is essential for viability and its depletion from the female germline causes infertility associated with global loss of heterochromatin, and illicit upregulation of transposons and lineage-inappropriate genes. However, the specific targets of SUMO and its mechanistic role in different cellular pathways are still poorly understood. Here, we developed a proteomics-based strategy to characterize the SUMOylated proteome in Drosophila that allowed us to identify ~1500 SUMO sites in 843 proteins in the fly ovary. A high-confidence set of SUMOylated proteins is highly enriched in factors involved in heterochromatin regulation and several different aspects of the piRNA pathway that represses transposons, including piRNA biogenesis and function. Furthermore, we show that SUMOylation of several piRNA pathway proteins occurs in a Piwi-dependent manner, indicating a functional implication of this modification in the cellular response to transposon activity. Together, these data highlight the impact of SUMOylation on epigenetic regulation and reveal an unexpectedly broad role of the SUMO pathway in the cellular defense against genomic parasites. Finally, this work provides a valuable resource and a system that can be adapted to the study of SUMOylation in other Drosophila tissues.
]]></description>
<dc:creator>Ninova, M.</dc:creator>
<dc:creator>Lomenick, B.</dc:creator>
<dc:creator>Fejes-Toth, K.</dc:creator>
<dc:creator>Aravin, A. A.</dc:creator>
<dc:date>2022-08-15</dc:date>
<dc:identifier>doi:10.1101/2022.08.15.504007</dc:identifier>
<dc:title><![CDATA[Pervasive SUMOylation of heterochromatin and piRNA pathway proteins]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.21.504714v1?rss=1">
<title>
<![CDATA[
Combinatorial expression motifs in signaling pathways 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.21.504714v1?rss=1</link>
<description><![CDATA[
Cell-cell signaling pathways comprise sets of variant receptors that are expressed in different combinations in different cell types. This architecture allows one pathway to be used in a variety of configurations, which could provide distinct functional capabilities, such as responding to different ligand variants. While individual pathways have been well-studied, we have lacked a comprehensive understanding of what receptor combinations are expressed and how they are distributed across cell types. Here, combining data from multiple single-cell gene expression atlases, we analyzed the expression profiles of core signaling pathways, including TGF-{beta}, Notch, Wnt, and Eph-ephrin, as well as non-signaling pathways. In many pathways, a limited set of receptor expression profiles are used recurrently in many distinct cell types. While some recurrent profiles are restricted to groups of closely related cells, others, which we term pathway expression motifs, reappear in distantly related cell types spanning diverse tissues and organs. Motif usage was generally uncorrelated between pathways, remained stable in a given cell type during aging, but could change in sudden punctuated transitions during development. These results suggest a mosaic view of pathway usage, in which the same core pathways can be active in many or most cell types, but operate in one of a handful of distinct modes.
]]></description>
<dc:creator>Granados, A. A.</dc:creator>
<dc:creator>Kanrar, N.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:date>2022-08-22</dc:date>
<dc:identifier>doi:10.1101/2022.08.21.504714</dc:identifier>
<dc:title><![CDATA[Combinatorial expression motifs in signaling pathways]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.23.505044v1?rss=1">
<title>
<![CDATA[
Structural remodeling of Coxiella burnetii during its biphasic developmental cycle revealedby cryo-electron tomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.23.505044v1?rss=1</link>
<description><![CDATA[
Coxiella burnetii is an obligate zoonotic bacterium that targets macrophages to cause a disease known as Q fever. It has a biphasic developmental lifecycle where the extracellular and metabolically inactive small cell variant (SCV) transforms, under host acidic environment, into the vegetative large cell variant (LCV). However, the details about the morphological and structural changes that accompany this biphasic cycle are still lacking. Here, we used cryo-electron tomography to image the different cell variants of C. burnetii grown either under axenic conditions in different pH or purified directly from host cells revealing the major developmental, morphological and structural transitions. We show that SCVs are characterized by equidistant stacks of inner membrane that presumably allow a smooth transition to LCV, a transition coupled with the expression of the Dot/Icm type IVB secretion system (T4BSS). A class of T4BSS particles were associated with extracellular densities including a tubular structure possibly involved in host interaction or effector delivery. Also, SCVs and cells in the transition state contained spherical multilayered membrane structures of different sizes and locations suggesting that they are not related to a sporulation process as once assumed.
]]></description>
<dc:creator>Kaplan, M.</dc:creator>
<dc:creator>Shepherd, D. C.</dc:creator>
<dc:creator>Vankadari, N.</dc:creator>
<dc:creator>Kim, K. W.</dc:creator>
<dc:creator>Larson, C. L.</dc:creator>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Beare, P. A.</dc:creator>
<dc:creator>Krzymowski, E.</dc:creator>
<dc:creator>Heinzen, R. A.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Ghosal, D.</dc:creator>
<dc:date>2022-08-24</dc:date>
<dc:identifier>doi:10.1101/2022.08.23.505044</dc:identifier>
<dc:title><![CDATA[Structural remodeling of Coxiella burnetii during its biphasic developmental cycle revealedby cryo-electron tomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.26.505369v1?rss=1">
<title>
<![CDATA[
Timeline of changes in spike conformational dynamics in emergent SARS-CoV-2 variants reveal progressive stabilization of trimer stalk and enhanced NTD dynamics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.26.505369v1?rss=1</link>
<description><![CDATA[
SARS-CoV-2 emergent variants are characterized by increased transmissibility and each show multiple mutations predominantly localized to the spike (S) protein. Here, amide hydrogen/deuterium exchange mass spectrometry has been applied to track correlative changes in S dynamics from multiple SARS-CoV-2 variants. Our results highlight large differences across variants at two loci with impacts on S dynamics and stability. A significant enhancement in stabilization first occurred with the emergence of D614G S followed by smaller, progressive stabilization in Omicron BA.1 S traced through Alpha S and Delta S variants. Stabilization preceded progressive enhancement in dynamics in the N-terminal domain, wherein Omicron BA.1 S showed the largest magnitude increases relative to other preceding variants. Changes in stabilization and dynamics resulting from specific S mutations detail the evolutionary trajectory of S protein in emerging variants. These carry major implications for SARS-CoV-2 viral fitness and offer new insights into variant-specific therapeutic development.
]]></description>
<dc:creator>Braet, S. M.</dc:creator>
<dc:creator>Buckley, T. S.</dc:creator>
<dc:creator>Venkatakrishnan, V.</dc:creator>
<dc:creator>Dam, K.-M. A.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Anand, G. S.</dc:creator>
<dc:date>2022-08-29</dc:date>
<dc:identifier>doi:10.1101/2022.08.26.505369</dc:identifier>
<dc:title><![CDATA[Timeline of changes in spike conformational dynamics in emergent SARS-CoV-2 variants reveal progressive stabilization of trimer stalk and enhanced NTD dynamics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.29.505313v1?rss=1">
<title>
<![CDATA[
S1 represents multisensory contexts and somatotopic locations within and outside the bounds of the cortical homunculus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.29.505313v1?rss=1</link>
<description><![CDATA[
The responsiveness of primary somatosensory cortex (S1) to physical tactile stimuli is well documented but the extent to which it is modulated by vision is unresolved. Additionally, recent literature has suggested that tactile events are represented in S1 in a more complex, generalized manner than its long-established topographic organization. To better characterize S1 function, neural activity was recorded from a tetraplegic patient implanted with microelectrode arrays in S1 during 1s stroking touches to the forearm (evoking numb sensation) or finger (naturalistic sensation). Touch conditions included visually observed first person physical touches, physical touches without vision, and visual touches without physical contact which occurred either to a third person, an inanimate object, or the patients own body in virtual reality. Two major findings emerged from this dataset. The first was that vision strongly modulates S1 activity, but only if there is a physical element to the touch, suggesting that passive observation of touches is not sufficient to recruit S1 neurons. The second was that despite the location of the recording arrays in a putative arm area of S1, neural activity was able to represent both arm and finger touches in physical touch conditions. Arm touches were encoded more strongly and specifically, supporting the idea that S1 encodes tactile events primarily through its topographic organization, as well as in a more general manner encompassing larger areas of the body.
]]></description>
<dc:creator>Rosenthal, I. A.</dc:creator>
<dc:creator>Bashford, L.</dc:creator>
<dc:creator>Kellis, S.</dc:creator>
<dc:creator>Pejsa, K.</dc:creator>
<dc:creator>Lee, B.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2022-08-31</dc:date>
<dc:identifier>doi:10.1101/2022.08.29.505313</dc:identifier>
<dc:title><![CDATA[S1 represents multisensory contexts and somatotopic locations within and outside the bounds of the cortical homunculus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.31.505972v1?rss=1">
<title>
<![CDATA[
CRISPR Mediated Transactivation in the Human Disease Vector Aedes aegypti 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.31.505972v1?rss=1</link>
<description><![CDATA[
As a major insect vector of multiple arboviruses, Aedes aegypti poses a significant global health and economic burden. A number of genetic engineering tools have been exploited to understand its biology with the goal of reducing its impact. For example, current tools have focused on knocking-down RNA transcripts, inducing loss-of-function mutations or expressing exogenous DNA. However, methods for transactivating endogenous genes have not been developed. To fill this void, here we developed a CRISPR activation (CRISPRa) system in Ae. aegypti to transactivate target gene expression. Gene expression is activated through pairing a catalytically-inactive ( dead) Cas9 (dCas9) with a highly-active tripartite activator, VP64-p65-Rta (VPR) and synthetic guide RNA (sgRNA) complementary to a user defined target-gene promoter region. As a proof of concept, we demonstrate that engineered Ae. aegypti mosquitoes harboring a binary CRISPRa system can be used to effectively overexpress two developmental genes, even-skipped (eve) and hedgehog (hh), resulting in observable morphological phenotypes. We also used this system to overexpress the positive transcriptional regulator of the Toll immune pathway known as AaRel1, which resulted in a significant suppression of dengue virus serotype 2 (DENV2). This system provides a versatile tool for research pathways not previously possible in Ae. aegypti, such as programmed overexpression of endogenous genes, and may lead to the development of innovative vector control tools.
]]></description>
<dc:creator>Bui, M.</dc:creator>
<dc:creator>Benetta, E. D.</dc:creator>
<dc:creator>Dong, Y.</dc:creator>
<dc:creator>Zhao, Y.</dc:creator>
<dc:creator>Yang, T.</dc:creator>
<dc:creator>Li, M.</dc:creator>
<dc:creator>Antoshechkin, I. A.</dc:creator>
<dc:creator>Buchman, A.</dc:creator>
<dc:creator>Bottino-Rojas, V.</dc:creator>
<dc:creator>James, A. A.</dc:creator>
<dc:creator>Perry, M. W.</dc:creator>
<dc:creator>Dimopoulos, G.</dc:creator>
<dc:creator>Akbari, O.</dc:creator>
<dc:date>2022-09-02</dc:date>
<dc:identifier>doi:10.1101/2022.08.31.505972</dc:identifier>
<dc:title><![CDATA[CRISPR Mediated Transactivation in the Human Disease Vector Aedes aegypti]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.31.506045v1?rss=1">
<title>
<![CDATA[
PEZO-1 and TRP-4 mechanosensors are involved in mating behavior in Caenorhabditis elegans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.31.506045v1?rss=1</link>
<description><![CDATA[
Male mating in Caenorhabditis elegans is a complex behavior with a strong mechanosensory component. C. elegans has several characterized mechanotransducer proteins, but few have been shown to contribute to mating. Here, we investigated the roles of PEZO-1, a piezo channel, and TRP-4, a mechanotransducing TRPN channel, in male mating behavior. We show that pezo-1 is expressed in several male-specific neurons with known roles in mating. We show that, among other neurons, trp-4 is expressed in the PCA sensory neuron, which monitors relative sliding between the male and the hermaphrodite and inhibits neurons involved in vulva detection. Mutations in both genes compromise many steps of mating, including initial response to the hermaphrodite, scanning, turning, and vulva detection. We performed pan-neuronal imaging during mating between freely-moving mutant males and hermaphrodites. Both pezo-1 and trp-4 mutants showed spurious activation of the sensory neurons involved in vulva detection. In trp-4 mutants, this spurious activation might be caused by PCA failure to inhibit vulva-detecting neurons during scanning. Indeed, we show that without functional TRP-4, PCA fails to detect the relative sliding between the male and hermaphrodite. Cell-specific TRP-4 expression restores PCAs mechanosensory function. Our results demonstrate new roles for both PEZO-1 and TRP-4 mechanotransducers in C. elegans mating behavior.
]]></description>
<dc:creator>Brugman, K. I.</dc:creator>
<dc:creator>Susoy, V.</dc:creator>
<dc:creator>Whittaker, A. J.</dc:creator>
<dc:creator>Palma, W.</dc:creator>
<dc:creator>Nava, S.</dc:creator>
<dc:creator>Samuel, A. D.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2022-09-01</dc:date>
<dc:identifier>doi:10.1101/2022.08.31.506045</dc:identifier>
<dc:title><![CDATA[PEZO-1 and TRP-4 mechanosensors are involved in mating behavior in Caenorhabditis elegans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.01.506248v1?rss=1">
<title>
<![CDATA[
A model-free Data-Driven paradigm for in situ patient-specific prediction of human brain response to ultrasound stimulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.01.506248v1?rss=1</link>
<description><![CDATA[
We present a class of model-free Data-Driven solvers that effectively enable the utilization of in situ and in vivo imaging data directly in full-scale calculations of the mechanical response of the human brain to sonic and ultrasonic stimulation, entirely bypassing the need for analytical modeling or regression of the data. The well-posedness of the approach and its convergence with respect to data are proven analytically. We demonstrate the approach, including its ability to make detailed spatially-resolved patient-specific predictions of wave patterns, using public-domain MRI images, MRE data and commercially available solid-mechanics software.
]]></description>
<dc:creator>Salahshoor, H.</dc:creator>
<dc:creator>Ortiz, M.</dc:creator>
<dc:date>2022-09-03</dc:date>
<dc:identifier>doi:10.1101/2022.09.01.506248</dc:identifier>
<dc:title><![CDATA[A model-free Data-Driven paradigm for in situ patient-specific prediction of human brain response to ultrasound stimulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.01.506257v1?rss=1">
<title>
<![CDATA[
Random and natural non-coding RNA have similar structural motif patterns but can be distinguished by bulge, loop, and bond counts 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.01.506257v1?rss=1</link>
<description><![CDATA[
An important question in evolutionary biology is whether and in what ways genotype-phenotype (GP) map biases can influence evolutionary trajectories. Untangling the relative roles of natural selection and biases (and other factors) in shaping phenotypes can be difficult. Because RNA secondary structure (SS) can be analysed in detail mathematically and computationally, is biologically relevant, and a wealth of bioinformatic data is available, it offers a good model system for studying the role of bias. For quite short RNA (length L [&le;] 126), it has recently been shown that natural and random RNA are structurally very similar, suggesting that bias strongly constrains evolutionary dynamics. Here we extend these results with emphasis on much larger RNA with length up to 3000 nucleotides. By examining both abstract shapes and structural motif frequencies (ie the numbers of helices, bonds, bulges, junctions, and loops), we find that large natural and random structures are also very similar, especially when contrasted to typical structures sampled from the space of all possible RNA structures. Our motif frequency study yields another result, that the frequencies of different motifs can be used in machine learning algorithms to classify random and natural RNA with quite high accuracy, especially for longer RNA (eg ROC AUC 0.86 for L = 1000). The most important motifs for classification are found to be the number of bulges, loops, and bonds. This finding may be useful in using SS to detect candidates for functional RNA within  junk DNA regions.
]]></description>
<dc:creator>Ghaddar, F.</dc:creator>
<dc:creator>Dingle, K.</dc:creator>
<dc:date>2022-09-03</dc:date>
<dc:identifier>doi:10.1101/2022.09.01.506257</dc:identifier>
<dc:title><![CDATA[Random and natural non-coding RNA have similar structural motif patterns but can be distinguished by bulge, loop, and bond counts]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.02.506334v1?rss=1">
<title>
<![CDATA[
A cryogenic, coincident fluorescence, electron and ion beam microscope 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.02.506334v1?rss=1</link>
<description><![CDATA[
Cryogenic electron tomography (cryo-ET) combined with sub-tomogram averaging, allows in-situ visualisation and structure determination of macromolecular complexes at sub-nanometre resolution. Cryogenic focused ion beam (cryo-FIB) micromachining is used to prepare a thin lamella-shaped sample out of a frozen-hydrated cell for cryo-ET imaging, but standard cryo-FIB fabrication is blind to the precise location of the structure or proteins of interest. Fluorescence-guided focused ion beam (FIB) milling at target locations requires multiple sample transfers prone to contamination, and relocation and registration accuracy is often insufficient for 3D targeting. Here, we present in-situ fluoresence microscopy-guided FIB fabrication of a frozen-hydrated lamella to solve this problem: we built a coincident 3-beam cryogenic correlative microscope by retrofitting a compact cryogenic microcooler, custom positioning stage, and an inverted widefield fluorescence microscope (FM) on an existing focused ion-beam scanning electron microscope (FIB-SEM). We show FM controlled targeting at every milling step in the lamella fabrication process, validated with transmission electron microscope (TEM) tomogram reconstructions of the target regions. The ability to check the lamella during and after the milling process results in a higher success rate in the fabrication process and will increase the throughput of fabrication for lamellae suitable for high-resolution imaging.
]]></description>
<dc:creator>Boltje, D.</dc:creator>
<dc:creator>Hoogenboom, J.</dc:creator>
<dc:creator>Jakobi, A. J.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Jonker, C.</dc:creator>
<dc:creator>Kaag, M.</dc:creator>
<dc:creator>Koster, A. J.</dc:creator>
<dc:creator>Last, M.</dc:creator>
<dc:creator>de Agrela Pinto, C.</dc:creator>
<dc:creator>Plitzko, J. M.</dc:creator>
<dc:creator>Raunser, S.</dc:creator>
<dc:creator>Tacke, S.</dc:creator>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>van der Wee, E.</dc:creator>
<dc:creator>Wepf, R.</dc:creator>
<dc:creator>den Hoedt, S.</dc:creator>
<dc:date>2022-09-03</dc:date>
<dc:identifier>doi:10.1101/2022.09.02.506334</dc:identifier>
<dc:title><![CDATA[A cryogenic, coincident fluorescence, electron and ion beam microscope]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.06.506071v1?rss=1">
<title>
<![CDATA[
Cognition through internal models: Mirror neurons as one manifestation of a broader mechanism 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.06.506071v1?rss=1</link>
<description><![CDATA[
Cognition relies on transforming sensory inputs into a more generalizable understanding. Mirror neurons are proposed to underlie this process, yet they fail to explain many key features of human thinking and learning. Here we hypothesize that mirror-like responses are one limited view into a more general framework by which internal models of the world are built and used. We recorded populations of single neurons in the human posterior parietal cortex as a participant felt or observed diverse tactile stimuli. We found that mirror-like responses were fragile and embedded within a richer population response that encoded generalizable and compositional features of the stimuli. We speculate that populations of neurons support versatile understanding, not through mirroring, but instead by encoding representational building blocks of cognition.

One-Sentence SummarySimilar neural responses during observed and experienced sensations are mediated by shared compositional building blocks, not mirror neurons.
]]></description>
<dc:creator>Aflalo, T.</dc:creator>
<dc:creator>Chivukula, S.</dc:creator>
<dc:creator>Zhang, C.</dc:creator>
<dc:creator>Rosario, E. R.</dc:creator>
<dc:creator>Pouratian, N.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2022-09-08</dc:date>
<dc:identifier>doi:10.1101/2022.09.06.506071</dc:identifier>
<dc:title><![CDATA[Cognition through internal models: Mirror neurons as one manifestation of a broader mechanism]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.06.506798v1?rss=1">
<title>
<![CDATA[
An extracellular vesicle targeting ligand that binds to Arc proteins and facilitates Arc transport in vivo 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.06.506798v1?rss=1</link>
<description><![CDATA[
Communication between distant cells can be mediated by extracellular vesicles (EVs) that deliver proteins and RNAs to recipient cells. Little is known about how EVs are targeted to specific cell types. Here we identify the Drosophila cell-surface protein Stranded at second (Sas) as a targeting ligand for EVs. Full-length Sas is present in EV preparations from transfected Drosophila Schneider 2 (S2 cells). Sas is a binding partner for the Ptp10D receptor tyrosine phosphatase, and Sas-bearing EVs preferentially target to cells expressing Ptp10D. We used co-immunoprecipitation and peptide binding to show that the cytoplasmic domain (ICD) of Sas binds to dArc1. dArc1 and mammalian Arc are related to retrotransposon Gag proteins. They form virus-like capsids which encapsulate Arc and other mRNAs and are transported between cells via EVs. The Sas ICD contains a motif required for dArc1 binding that is shared by the mammalian and Drosophila amyloid precursor protein (APP) orthologs, and the Sas and APP ICDs also bind to mammalian Arc. Sas facilitates delivery of dArc1 capsids bearing dArc1 mRNA into distant Ptp10D-expressing recipient cells in vivo.
]]></description>
<dc:creator>Lee, P. H.</dc:creator>
<dc:creator>Anaya, M.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Reitsma, J.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:date>2022-09-08</dc:date>
<dc:identifier>doi:10.1101/2022.09.06.506798</dc:identifier>
<dc:title><![CDATA[An extracellular vesicle targeting ligand that binds to Arc proteins and facilitates Arc transport in vivo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.08.507175v1?rss=1">
<title>
<![CDATA[
Robust control of replication initiation in the absence of DnaA-ATP {leftrightharpoons} DnaA-ADP regulatory elements in Escherichia coli 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.08.507175v1?rss=1</link>
<description><![CDATA[
Investigating a long-standing conceptual question in bacterial physiology, we examine why DnaA, the bacterial master replication initiator protein, exists in both ATP and ADP forms, despite only the ATP form being essential for initiation. We engineered the {Delta}4 Escherichia coli strain, devoid of all known external elements facilitating the DnaA-ATP/ADP conversion, and found that these cells display nearly wild-type behaviors under non-overlapping replication cycles. However, during rapid growth with overlapping cycles, {Delta}4 cells exhibit initiation instability. This aligns with our model predictions, suggesting that the intrinsic ATPase activity of DnaA alone is sufficient for robust initiation control in E. coli and the DnaA-ATP/ADP conversion regulatory elements extend the robustness to multifork replication, indicating an evolutionary adaptation. Moreover, our experiments revealed constant DnaA concentrations during steady-state cell elongation in both wild-type and {Delta}4 cells. These insights not only advance our understanding of bacterial cell-cycle regulation and DnaA, but also highlight a fundamental divergence from eukaryotic cell-cycle controls, emphasizing protein copy-number sensing in bacteria versus programmed protein concentration oscillations in eukaryotes.
]]></description>
<dc:creator>Boesen, T.</dc:creator>
<dc:creator>Charbon, G.</dc:creator>
<dc:creator>Fu, H.</dc:creator>
<dc:creator>Jensen, C.</dc:creator>
<dc:creator>Li, D.</dc:creator>
<dc:creator>Jun, S.</dc:creator>
<dc:creator>Lobner-Olesen, A.</dc:creator>
<dc:date>2022-09-08</dc:date>
<dc:identifier>doi:10.1101/2022.09.08.507175</dc:identifier>
<dc:title><![CDATA[Robust control of replication initiation in the absence of DnaA-ATP {leftrightharpoons} DnaA-ADP regulatory elements in Escherichia coli]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.09.507302v1?rss=1">
<title>
<![CDATA[
Bacterial Argonaute nucleases reveal different modes of DNA targeting in vitro and in vivo 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.09.507302v1?rss=1</link>
<description><![CDATA[
Prokaryotic Argonaute proteins (pAgos) are homologs of eukaryotic Argonautes (eAgos) that were similarly proposed to play a role in cell defense against invaders. However, pAgos are much more diverse than eAgos and very little is known about their functional activity and target specificity in vivo. Here, we describe five pAgo proteins from mesophilic bacteria that act as DNA-guided DNA endonucleases and analyze their ability to target chromosomal and invader DNA. In vitro, the analyzed proteins use small guide DNAs for precise cleavage of single-stranded DNA at a wide range of temperatures. Upon their expression in Escherichia coli, all five pAgos are loaded with small DNAs preferentially produced from plasmid DNA and from chromosomal regions of replication termination. One of the tested pAgos, EmaAgo from Exiguobacterium marinum can induce DNA interference between multicopy sequences resulting in targeted processing of homologous plasmid and chromosomal loci. EmaAgo also protects bacteria from bacteriophage infection and is preferentially loaded with phage guide DNAs suggesting that the ability of pAgos to target multicopy elements may be crucial for their protective function. The wide spectrum of pAgo activities suggests that they may have diverse functions in vivo and paves the way for their use in biotechnology.
]]></description>
<dc:creator>Lisitskaya, L.</dc:creator>
<dc:creator>Kropocheva, E.</dc:creator>
<dc:creator>Agapov, A.</dc:creator>
<dc:creator>Prostova, M.</dc:creator>
<dc:creator>Panteleev, V.</dc:creator>
<dc:creator>Yudin, D.</dc:creator>
<dc:creator>Ryazansky, S.</dc:creator>
<dc:creator>Kuzmenko, A.</dc:creator>
<dc:creator>Aravin, A.</dc:creator>
<dc:creator>Esyunina, D.</dc:creator>
<dc:creator>Kulbachiskiy, A.</dc:creator>
<dc:date>2022-09-09</dc:date>
<dc:identifier>doi:10.1101/2022.09.09.507302</dc:identifier>
<dc:title><![CDATA[Bacterial Argonaute nucleases reveal different modes of DNA targeting in vitro and in vivo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.09.507322v1?rss=1">
<title>
<![CDATA[
Quantum Biology in Cellular Migration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.09.507322v1?rss=1</link>
<description><![CDATA[
The impact of magnetic fields on cellular function is diverse but can be described at least in part by the Radical Pair Mechanism (RPM), where magnetic field intervention alters reactive oxygen species (ROS) populations and downstream cellular signaling. Here, cellular magnetophoresis within three-dimensional scaffolds was monitored in an applied oscillating 1.4 MHz radiofrequency (RF) magnetic field with an amplitude of 10 T and a static 50 T magnetic field. Given that cellular respiration or glycolysis can be increased based on the orientation of the RF magnetic field, this study focused on the parallel orientation to increase ATP synthesis. Results suggest that RF accelerated clustering and elongation after 1 day with increased levels of clustering and cellular linkage after 7 days. Electron microscopy provided additional topological information and verified the development of fibrous networks and extracellular matrix were visualized after 7 days in samples maintained in RF. Analysis of the distribution of cells within the scaffolds revealed that the clustering rate during the first day was increased nearly five times in the RF environment. This work demonstrates time-dependent cellular magnetophoresis that may be influenced by quantum biology (QB) processes and signaling that can further attenuate or enhance cellular bioenergetics and behavior.
]]></description>
<dc:creator>Vecheck, A.</dc:creator>
<dc:creator>McNamee, C.</dc:creator>
<dc:creator>Reijo Pera, R. A.</dc:creator>
<dc:creator>Usselman, R.</dc:creator>
<dc:date>2022-09-14</dc:date>
<dc:identifier>doi:10.1101/2022.09.09.507322</dc:identifier>
<dc:title><![CDATA[Quantum Biology in Cellular Migration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.12.507655v1?rss=1">
<title>
<![CDATA[
Drosophila Males Use 5'-to-3' Phased Biogenesis to Make Stellate-silencing piRNAs that Lack Homology to Maternally Deposited piRNA Guides 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.12.507655v1?rss=1</link>
<description><![CDATA[
PIWI-interacting RNAs (piRNAs) direct PIWI proteins to silence complementary targets such as transposons. In animals with a maternally specified germline, e.g. Drosophila melanogaster, maternally deposited piRNAs initiate piRNA biogenesis in the progeny. Normal fertility in D. melanogaster males requires repression of tandemly repeated Stellate genes by piRNAs from Suppressor of Stellate [Su(Ste)]. Because the Su(Ste) loci are on the Y chromosome, Su(Ste) piRNAs are not deposited in oocytes. How the male germline produces Su(Ste) piRNAs in the absence of maternally deposited Su(Ste) piRNAs is unknown. Here, we show that Su(Ste) piRNAs are made in the early male germline via 5'-to-3' phased piRNA biogenesis triggered by maternally deposited 1360/Hoppel transposon piRNAs. Strikingly, deposition of Su(Ste) piRNAs from XXY mothers obviates the need for phased piRNA biogenesis in sons. Together, our study uncovers the developmentally programmed mechanism that allows fly mothers to protect their sons using a Y-linked piRNA locus.
]]></description>
<dc:creator>Venkei, Z. G.</dc:creator>
<dc:creator>Gainetdinov, I.</dc:creator>
<dc:creator>Starostik, M.</dc:creator>
<dc:creator>Choi, C.</dc:creator>
<dc:creator>Chen, P.</dc:creator>
<dc:creator>Balsara, C.</dc:creator>
<dc:creator>Whitfield, T.</dc:creator>
<dc:creator>Bell, G. W.</dc:creator>
<dc:creator>Feng, S.</dc:creator>
<dc:creator>Jacobsen, S. E.</dc:creator>
<dc:creator>Aravin, A.</dc:creator>
<dc:creator>Kim, J. K.</dc:creator>
<dc:creator>Zamore, P.</dc:creator>
<dc:creator>Yamashita, Y. M.</dc:creator>
<dc:date>2022-09-13</dc:date>
<dc:identifier>doi:10.1101/2022.09.12.507655</dc:identifier>
<dc:title><![CDATA[Drosophila Males Use 5'-to-3' Phased Biogenesis to Make Stellate-silencing piRNAs that Lack Homology to Maternally Deposited piRNA Guides]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.13.507849v1?rss=1">
<title>
<![CDATA[
Bacterial Argonaute proteins aid cell division in the presence of topoisomerase inhibitors in Escherichia coli 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.13.507849v1?rss=1</link>
<description><![CDATA[
Prokaryotic Argonaute (pAgo) proteins are guide-dependent nucleases that function in host defense against invaders. Recently, it was shown that TtAgo from Thermus thermophilus also participates in the completion of DNA replication by decatenating chromosomal DNA. Here, we show that two pAgos from cyanobacteria Synechococcus elongatus (SeAgo) and Limnothrix roseae (LrAgo) act as DNA-guided DNA nucleases in Escherichia coli and aid cell division in the presence of the gyrase inhibitor ciprofloxacin. Both pAgos are preferentially loaded with small DNA guides derived from the sites of replication termination. The amount of pAgo-associated small DNAs (smDNAs) from the termination sites is increased in the presence ciprofloxacin, suggesting that smDNA biogenesis depends on DNA replication and is stimulated by gyrase inhibition. Ciprofloxacin also enhances asymmetry in the distribution of smDNAs around Chi-sites, indicating that it induces double-strand breaks that serve as a source of smDNA during their processing by RecBCD. While active in E. coli, SeAgo does not protect its native host S. elongatus from ciprofloxacin. These results suggest that pAgo nucleases help to complete replication of chromosomal DNA by targeting the sites of termination, and may switch their functional activities when expressed in different host species.
]]></description>
<dc:creator>Olina, A.</dc:creator>
<dc:creator>Agapov, A.</dc:creator>
<dc:creator>Yudin, D.</dc:creator>
<dc:creator>Kuzmenko, A.</dc:creator>
<dc:creator>Aravin, A. A.</dc:creator>
<dc:creator>Kulbachiskiy, A.</dc:creator>
<dc:date>2022-09-13</dc:date>
<dc:identifier>doi:10.1101/2022.09.13.507849</dc:identifier>
<dc:title><![CDATA[Bacterial Argonaute proteins aid cell division in the presence of topoisomerase inhibitors in Escherichia coli]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.15.508165v1?rss=1">
<title>
<![CDATA[
MTCH2 is a mitochondrial outer membrane protein insertase 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.15.508165v1?rss=1</link>
<description><![CDATA[
In the mitochondrial outer membrane, tail-anchored (TA) proteins play critical roles in cytoplasmic-mitochondrial communication. Using genome-wide CRISPRi screens, we identify factors involved in mitochondrial TA biogenesis in human cells. We show that MTCH2, and its paralog MTCH1, are required for insertion of biophysically diverse mitochondrial TAs, but not outer membrane {beta}-barrel proteins. In a reconstituted system, purified MTCH2 is sufficient to mediate insertion into proteoliposomes. Functional and mutational studies reveal that MTCH2 uses membrane-embedded hydrophilic residues to function as a gatekeeper for outer membrane protein biogenesis, controlling mislocalization of TAs into the endoplasmic reticulum and the sensitivity of leukemia cells to apoptosis. Our identification of MTCH2 as an insertase provides a mechanistic explanation for the diverse phenotypes and disease states associated with MTCH2 dysfunction.

One-Sentence SummaryMTCH2 is both necessary and sufficient for insertion of diverse -helical proteins into the mitochondrial outer membrane, and is the defining member of a family of insertases that have co-opted the SLC25 transporter fold.
]]></description>
<dc:creator>Guna, A.</dc:creator>
<dc:creator>Stevens, T. A.</dc:creator>
<dc:creator>Inglis, A. J.</dc:creator>
<dc:creator>Replogle, J. M.</dc:creator>
<dc:creator>Esantsi, T. K.</dc:creator>
<dc:creator>Muthukumar, G.</dc:creator>
<dc:creator>Shaffer, K. C. L.</dc:creator>
<dc:creator>Wang, M. L.</dc:creator>
<dc:creator>Pogson, A. N.</dc:creator>
<dc:creator>Jones, J. J.</dc:creator>
<dc:creator>Lomenick, B.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Weissman, J. S.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:date>2022-09-16</dc:date>
<dc:identifier>doi:10.1101/2022.09.15.508165</dc:identifier>
<dc:title><![CDATA[MTCH2 is a mitochondrial outer membrane protein insertase]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.15.508205v1?rss=1">
<title>
<![CDATA[
Electrochemical disruption of extracellular electron transfer inhibits Pseudomonas aeruginosa cell survival within biofilms and is synergistic with antibiotic treatment 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.15.508205v1?rss=1</link>
<description><![CDATA[
Survival of cells within oxygen-limited regions in Pseudomonas aeruginosa biofilms is enabled by using small redox active molecules as electron shuttles to access distal oxidants. This respiratory versatility makes P. aeruginosa biofilms common in chronic wound infections and recalcitrant to treatment. Here, we show that electrochemically controlling the redox state of these electron shuttles, specifically pyocyanin, can impact cell survival within anaerobic P. aeruginosa biofilms and can act synergistically with antibiotic treatment. We inhibited pyocyanin redox cycling under anoxic conditions by blocking its ability to be re-oxidized and thus serve as an electron shuttle via poising an electrode at a reductive potential that cannot regenerate oxidized pyocyanin (i.e. -400mV vs Ag/AgCl). This resulted in a decrease in CFUs within the biofilm of 100x compared to samples exposed to an electrode poised at an oxidizing potential that permits pyocyanin re-oxidation (i.e. +100mV vs Ag/AgCl). Phenazine-deficient {Delta}phz* biofilms were not affected by the redox potential of the electrode, but were re-sensitized by adding pyocyanin. The effect of EET disruption was exacerbated when biofilms were treated with sub-MICs of a range of antibiotics. Most notably, 4 g/ml of the aminoglycoside gentamicin in a reductive environment almost completely eradicated wild type biofilms but had no effect on the survival of {Delta}phz* biofilms, suggesting reduced phenazines are toxic, and combined with antibiotic treatment can lead to extensive killing.

ImportanceBiofilms provide a protective environment but they also present challenges to the cells living within them, such as overcoming diffusion limitation of nutrients and oxygen. Pseudomonas aeruginosa overcomes oxygen limitation by secreting soluble redox active molecules as electron shuttles to access distal oxygen. Here, we show that electrochemically blocking the redox cycling of one of these electron shuttles, pyocyanin, decreases cell survival within biofilms and acts synergistically with gentamicin to kill cells. Our results highlight the importance of the role that the redox cycling of electron shuttles fulfills within P. aeruginosa biofilms.
]]></description>
<dc:creator>Jimenez Otero, F.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:creator>Tender, L. M.</dc:creator>
<dc:date>2022-09-19</dc:date>
<dc:identifier>doi:10.1101/2022.09.15.508205</dc:identifier>
<dc:title><![CDATA[Electrochemical disruption of extracellular electron transfer inhibits Pseudomonas aeruginosa cell survival within biofilms and is synergistic with antibiotic treatment]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.18.508442v1?rss=1">
<title>
<![CDATA[
HCR Lateral Flow Assays for Amplified Instrument-Free At-Home SARS-CoV-2 Testing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.18.508442v1?rss=1</link>
<description><![CDATA[
The lateral flow assay format enables rapid, instrument-free, at-home testing for SARS-CoV-2. Due to the absence of signal amplification, this simplicity comes at a cost in sensitivity. Here, we enhance sensitivity by developing an amplified lateral flow assay that incorporates isothermal, enzyme-free signal amplification based on the mechanism of hybridization chain reaction (HCR). The simplicity of the user experience is maintained using a disposable 3-channel lateral flow device to automatically deliver reagents to the test region in three successive stages without user interaction. To perform a test, the user loads the sample, closes the device, and reads the result by eye after 60 minutes. Detecting gamma-irradiated SARS-CoV-2 virions in a mixture of saliva and extraction buffer, the current amplified HCR lateral flow assay achieves a limit of detection of 200 copies/L using available antibodies to target the SARS-CoV-2 nucleocapsid protein. By comparison, five commercial unamplified lateral flow assays that use proprietary antibodies exhibit limits of detection of 500 copies/L, 1000 copies/L, 2000 copies/L, 2000 copies/L, and 20,000 copies/L. By swapping out antibody probes to target different pathogens, amplified HCR lateral flow assays offer a platform for simple, rapid, and sensitive at-home testing for infectious disease. As an alternative to viral protein detection, we further introduce an HCR lateral flow assay for viral RNA detection.

HCR lateral flow assayO_LIAmplified
C_LIO_LIInstrument-free
C_LIO_LIAt-home
C_LIO_LI60 min
C_LIO_LINaked eye
C_LIO_LISARS-CoV-2
C_LIO_LI200 copies/L
C_LI



O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=166 SRC="FIGDIR/small/508442v1_ufig1.gif" ALT="Figure 1">
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]]></description>
<dc:creator>Schulte, S. J.</dc:creator>
<dc:creator>Huang, J.</dc:creator>
<dc:creator>Pierce, N. A.</dc:creator>
<dc:date>2022-09-19</dc:date>
<dc:identifier>doi:10.1101/2022.09.18.508442</dc:identifier>
<dc:title><![CDATA[HCR Lateral Flow Assays for Amplified Instrument-Free At-Home SARS-CoV-2 Testing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.19.508605v1?rss=1">
<title>
<![CDATA[
Evaluation of mouse behavioral responses to nutritive versus nonnutritive sugar using a deep learning-based 3D real-time pose estimation system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.19.508605v1?rss=1</link>
<description><![CDATA[
Animals are able to detect the nutritional content of sugar independently of taste. When given a choice between nutritive sugar and nonnutritive sugar, animals develop a preference for nutritive sugar over nonnutritive sugar during a period of food deprivation1-5. To quantify behavioral features during an episode of licking nutritive versus nonnutritive sugar, we implemented a multi-vision, deep learning-based 3D pose estimation system, termed the AI Vision Analysis for Three-dimensional Action in Real-Time (AVATAR)6. Using this method, we found that mice exhibit significantly different approach behavioral responses toward nutritive sugar versus nonnutritive sugar even before licking a sugar solution. Notably, the behavioral sequences during approach toward nutritive versus nonnutritive sugar became significantly different over time. These results suggest that the nutritional value of sugar not only promotes its consumption, but also elicits distinct repertoires of feeding behavior in deprived mice.
]]></description>
<dc:creator>Kim, J.</dc:creator>
<dc:creator>Kim, D.</dc:creator>
<dc:creator>Jung, W.</dc:creator>
<dc:creator>Suh, G. S. B.</dc:creator>
<dc:date>2022-09-19</dc:date>
<dc:identifier>doi:10.1101/2022.09.19.508605</dc:identifier>
<dc:title><![CDATA[Evaluation of mouse behavioral responses to nutritive versus nonnutritive sugar using a deep learning-based 3D real-time pose estimation system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.21.508902v1?rss=1">
<title>
<![CDATA[
Predicting phenotype transition probabilities via conditional algorithmic probability approximations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.21.508902v1?rss=1</link>
<description><![CDATA[
Unravelling the structure of genotype-phenotype (GP) maps is an important problem in biology. Recently, arguments inspired by algorithmic information theory (AIT) and Kolmogorov complexity have been invoked to uncover simplicity bias in GP maps, an exponentially decaying upper bound in phenotype probability with increasing phenotype descriptional complexity. This means that phenotypes with very many genotypes assigned via the GP map must be simple, while complex phenotypes must have few genotypes assigned. Here we use similar arguments to bound the probability P (x [-&gt;] y) that phenotype x, upon random genetic mutation, transitions to phenotype y. The bound is [Formula], where [Formula] is the estimated conditional complexity of y given x, quantifying how much extra information is required to make y given access to x. This upper bound is related to the conditional form of algorithmic probability from AIT. We demonstrate the practical applicability of our derived bound by predicting phenotype transition probabilities (and other related quantities) in simulations of RNA and protein secondary structures. Our work contributes to a general mathematical understanding of GP maps, and may facilitate the prediction of transition probabilities directly from examining phenotype themselves, without utilising detailed knowledge of the GP map.
]]></description>
<dc:creator>Dingle, K.</dc:creator>
<dc:creator>Novev, J. K.</dc:creator>
<dc:creator>Ahnert, S. E.</dc:creator>
<dc:creator>Louis, A. A.</dc:creator>
<dc:date>2022-09-22</dc:date>
<dc:identifier>doi:10.1101/2022.09.21.508902</dc:identifier>
<dc:title><![CDATA[Predicting phenotype transition probabilities via conditional algorithmic probability approximations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.21.508943v1?rss=1">
<title>
<![CDATA[
The Phosphate Deprivation Response is Mediated by an Interaction between Brassinosteroid Signaling and Zinc in Tomato 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.21.508943v1?rss=1</link>
<description><![CDATA[
Phosphate is a necessary macronutrient for basic biological processes, plant growth, and agriculture. Plants modulate their root system architecture and cellular processes to adapt to phosphate deprivation albeit with a growth penalty. Excess application of phosphate fertilizer, on the other hand, leads to eutrophication and has a negative environmental impact. Moreover, phosphate mined from rock reserves is a finite and non-recyclable resource and its levels are nearing complete depletion. Here, we show that Solanum pennellii, a wild relative of tomato, is partially insensitive to phosphate deprivation. Furthermore, it mounts a constitutive response under phosphate sufficiency. We demonstrate that activated brassinosteroid signaling through a tomato BZR1 ortholog gives rise to the same constitutive phosphate deficiency response, which is dependent on zinc over-accumulation. Collectively, these results reveal an additional strategy by which plants can adapt to phosphate starvation.
]]></description>
<dc:creator>Demirer, G. S.</dc:creator>
<dc:creator>Gibson, D. J.</dc:creator>
<dc:creator>Yue, X.</dc:creator>
<dc:creator>Pan, K.</dc:creator>
<dc:creator>Elishav, E.</dc:creator>
<dc:creator>Khandal, H.</dc:creator>
<dc:creator>Horev, G.</dc:creator>
<dc:creator>Tarkowska, D.</dc:creator>
<dc:creator>Canto-Pastor, A.</dc:creator>
<dc:creator>Kong, S.</dc:creator>
<dc:creator>Maloof, J.</dc:creator>
<dc:creator>Savaldi-Goldstein, S.</dc:creator>
<dc:creator>Brady, S.</dc:creator>
<dc:date>2022-09-22</dc:date>
<dc:identifier>doi:10.1101/2022.09.21.508943</dc:identifier>
<dc:title><![CDATA[The Phosphate Deprivation Response is Mediated by an Interaction between Brassinosteroid Signaling and Zinc in Tomato]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.25.509369v1?rss=1">
<title>
<![CDATA[
Cryo-EM structure of the Agrobacterium tumefaciens type IV secretion system-associated T-pilus reveals stoichiometric protein-phospholipid assembly 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.25.509369v1?rss=1</link>
<description><![CDATA[
Agrobacterium tumefaciens is a plant pathogen that causes crown gall disease by the horizontal transfer of oncogenic DNA that is integrated into the hosts genome. The conjugation is mediated by the conjugative VirB/D4 type 4 secretion system (T4SS). A. tumefaciens T4SS assembles an extracellular filament, the T-pilus, that is involved in the formation of a mating pair between A. tumefaciens and the recipient plant cell by a not fully understood mechanism. Here, we present a 3 [A] cryo-EM structure of the T-pilus, solved by helical reconstruction. Our structure reveals that the T-pilus comprises the major pilin protein VirB2 and phosphatidylglycerol (PG) phospholipid at a 1:1 stoichiometric ratio with 5-start helical symmetry. We further show that PG-headgroups and the positively charged Arg 91 residues of VirB2 protomers form extensive electrostatic interactions in the lumen of the T-pilus. Mutagenesis of Arg 91 destabilized the VirB2 protein and completely abolished pilus formation. While our T-pilus structure shows architectural similarity with previously published conjugative pili structures, positively charged sidechains protrude into the lumen and the lumen is narrower, raising questions whether the T-pilus is a conduit for ssDNA transfer. We also show that the VirB2 subunits in T-pilus filament are not cyclic, as previously thought.
]]></description>
<dc:creator>Kreida, S.</dc:creator>
<dc:creator>Narita, A.</dc:creator>
<dc:creator>Johnson, M. D.</dc:creator>
<dc:creator>Tocheva, E. I.</dc:creator>
<dc:creator>Das, A.</dc:creator>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2022-09-25</dc:date>
<dc:identifier>doi:10.1101/2022.09.25.509369</dc:identifier>
<dc:title><![CDATA[Cryo-EM structure of the Agrobacterium tumefaciens type IV secretion system-associated T-pilus reveals stoichiometric protein-phospholipid assembly]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.28.509596v1?rss=1">
<title>
<![CDATA[
Value-Based Neural Representations Predict Social Decision Preferences 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.28.509596v1?rss=1</link>
<description><![CDATA[
Social decision-making is omnipresent in everyday life, carrying the potential for both positive and negative consequences for the decision-maker and those closest to them. While evidence suggests that decision makers use value-based heuristics to guide choice behavior, very little is known about how decision makers representations of other agents influence social choice behavior. We used multivariate pattern expression analyses on fMRI data to understand how value-based processes shape neural representations of those affected by ones social decisions and whether value-based encoding is associated with social decision preferences. We found that stronger value-based encoding of a given close other (e.g., parent) relative to a second close other (e.g., friend) was associated with a greater propensity to favor the former during subsequent social decision-making. These results are the first to our knowledge to explicitly show that value-based processes affect decision behavior via representations of close others.
]]></description>
<dc:creator>Guassi Moreira, J. F.</dc:creator>
<dc:creator>Mendez Leal, A. S.</dc:creator>
<dc:creator>Waizman, Y. H.</dc:creator>
<dc:creator>Tashjian, S. M.</dc:creator>
<dc:creator>Galvan, A.</dc:creator>
<dc:creator>Silvers, J. A.</dc:creator>
<dc:date>2022-09-30</dc:date>
<dc:identifier>doi:10.1101/2022.09.28.509596</dc:identifier>
<dc:title><![CDATA[Value-Based Neural Representations Predict Social Decision Preferences]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.29.509334v1?rss=1">
<title>
<![CDATA[
Photoacoustic imaging reveals transient decrease of oxygenation in murine blood due to monoclonal IgG4 antibody 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.29.509334v1?rss=1</link>
<description><![CDATA[
Over 100 monoclonal antibodies have been approved by the FDA for clinical use; however, a paucity of knowledge exists regarding the injection site behavior of these formulated therapeutics, i.e., the effect of antibody and formulation on the tissue around the injection site and vice versa. In this report, we injected a near-infrared dye-labeled IgG4 isotope control antibody into the subcutaneous space in mouse ears to analyze the injection site dynamics, including quantifying molecular movement. Surprisingly, we discovered that the antibody reduces the local blood oxygen saturation levels in mice after prolonged anesthesia without affecting the total hemoglobin content and oxygen extraction fraction. The local oxygen saturation results open a new pathway to study the functional effects of monoclonal antibodies.
]]></description>
<dc:creator>Khadria, A.</dc:creator>
<dc:creator>Paavola, C. D.</dc:creator>
<dc:creator>Maslov, K.</dc:creator>
<dc:creator>Brown-Augsburger, P. L.</dc:creator>
<dc:creator>Grealish, P. F.</dc:creator>
<dc:creator>Lozano, E.</dc:creator>
<dc:creator>Blankenship, R. L.</dc:creator>
<dc:creator>Cao, R.</dc:creator>
<dc:creator>Shi, J.</dc:creator>
<dc:creator>Beals, J. M.</dc:creator>
<dc:creator>Oladipupo, S. S.</dc:creator>
<dc:creator>Wang, L. V.</dc:creator>
<dc:date>2022-10-03</dc:date>
<dc:identifier>doi:10.1101/2022.09.29.509334</dc:identifier>
<dc:title><![CDATA[Photoacoustic imaging reveals transient decrease of oxygenation in murine blood due to monoclonal IgG4 antibody]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.04.509789v1?rss=1">
<title>
<![CDATA[
Digital nanoreactors for control over absolute stoichiometry and spatiotemporal behavior of receptors within lipid bilayers 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.04.509789v1?rss=1</link>
<description><![CDATA[
Interactions between membrane proteins are essential for cell survival and proper function, but the structural and mechanistic details of these interactions are often poorly understood. Even the biologically functional ratio of protein components within a multi-subunit membrane complex--the native stoichiometry--is difficult to establish. We have demonstrated digital nanoreactors that can control interactions between lipid-bound molecular receptors along three key dimensions: stoichiometric, spatial, and temporal. Each nanoreactor is based on a DNA origami ring, which both templates the synthesis of a liposome and provides tethering sites for DNA-based receptors. Receptors are released into the liposomal membrane using strand displacement and a DNA logic gate measures receptor heterodimer formation. High-efficiency tethering of receptors enables the kinetics of receptors in 1:1 and 2:2 absolute stoichiometries to be observed by bulk fluorescence in a plate reader which in principle is generalizable to any ratio. Similar  single molecule in bulk experiments using DNA-linked membrane proteins could determine native stoichiometry and the kinetics of membrane protein interactions for applications ranging from signalling research to drug discovery.
]]></description>
<dc:creator>Maingi, V.</dc:creator>
<dc:creator>Zhang, Z.</dc:creator>
<dc:creator>Thachuk, C.</dc:creator>
<dc:creator>Sarraf, N.</dc:creator>
<dc:creator>Chapman, E. R.</dc:creator>
<dc:creator>Rothemund, P. W. K.</dc:creator>
<dc:date>2022-10-07</dc:date>
<dc:identifier>doi:10.1101/2022.10.04.509789</dc:identifier>
<dc:title><![CDATA[Digital nanoreactors for control over absolute stoichiometry and spatiotemporal behavior of receptors within lipid bilayers]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.04.510900v1?rss=1">
<title>
<![CDATA[
Control of spatio-temporal patterning via cell density in a multicellular synthetic gene circuit 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.04.510900v1?rss=1</link>
<description><![CDATA[
A major goal in synthetic development is to design and construct gene regulatory circuits that control the patterning and morphogenesis of synthetic multicellular structures. In natural development, an interplay between mechanical and chemical communication shapes the dynamics of gene regulatory circuits that underlie patterning and morphogenesis. However, for synthetic gene circuits, how the non-genetic properties of the growth environment impact circuit behavior remains poorly understood. Here, we describe an occurrence of mechano-chemical coupling in synthetic contact-dependent synNotch patterning circuits demonstrating that cell density modulates the transduction of signal between a sender and receiver cell. By exploiting density-dependent signaling, we construct multicellular signal propagation circuits with synNotch and control the patterning outcome both temporally and spatially via cell density gradients established in vitro via plating or small-molecule mediated modulation of proliferation. Our work demonstrates that synthetic gene circuits can be critically impacted by their context, providing an alternate means for programming multi-cellular circuit patterning outcomes.
]]></description>
<dc:creator>Santorelli, M.</dc:creator>
<dc:creator>Bhamidipati, P. S.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Morsut, L.</dc:creator>
<dc:date>2022-10-05</dc:date>
<dc:identifier>doi:10.1101/2022.10.04.510900</dc:identifier>
<dc:title><![CDATA[Control of spatio-temporal patterning via cell density in a multicellular synthetic gene circuit]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.05.511053v1?rss=1">
<title>
<![CDATA[
Characterization of Integrase and Excisionase Activity in Cell-free Protein Expression System Using a Modeling and Analysis Pipeline 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.05.511053v1?rss=1</link>
<description><![CDATA[
We present a full-stack modeling, analysis, and parameter identification pipeline to guide the modeling and design of biological systems starting from specifications to circuit implementations and parameterizations. We demonstrate this pipeline by characterizing the integrase and excisionase activity in cell-free protein expression system. We build on existing Python tools -- BioCRNpyler, AutoReduce, and Bioscrape -- to create this pipeline. For enzyme-mediated DNA recombination in cell-free system, we create detailed chemical reaction network models from simple high-level descriptions of the biological circuits and their context using BioCRNpyler. We use Bioscrape to show that the output of the detailed model is sensitive to many parameters. However, parameter identification is infeasible for this high-dimensional model, hence, we use AutoReduce to automatically obtain reduced models that have fewer parameters. This results in a hierarchy of reduced models under different assumptions to finally arrive at a minimal ODE model for each circuit. Then, we run sensitivity analysis-guided Bayesian inference using Bioscrape for each circuit to identify the model parameters. This process allows us to quantify integrase and excisionase activity in cell extracts enabling complex-circuit designs that depend on accurate control over protein expression levels through DNA recombination. The automated pipeline presented in this paper opens up a new approach to complex circuit design, modeling, reduction, and parameterization.
]]></description>
<dc:creator>Pandey, A.</dc:creator>
<dc:creator>Rodriguez, M. L.</dc:creator>
<dc:creator>Poole, W.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2022-10-06</dc:date>
<dc:identifier>doi:10.1101/2022.10.05.511053</dc:identifier>
<dc:title><![CDATA[Characterization of Integrase and Excisionase Activity in Cell-free Protein Expression System Using a Modeling and Analysis Pipeline]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.09.511501v1?rss=1">
<title>
<![CDATA[
Quantifying orthogonal barcodes for sequence census assays 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.09.511501v1?rss=1</link>
<description><![CDATA[
Barcode-based sequence census assays utilize custom or random oligonucloetide sequences to label various biological features, such as cell-surface proteins or CRISPR perturbations. These assays all rely on barcode quantification, a task that is complicated by barcode design and technical noise. We introduce a modular approach to quantifying barcodes that achieves speed and memory improvements over existing tools. We also introduce a set of quality control metrics, and accompanying tool, for validating barcode designs.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Min, K. H.</dc:creator>
<dc:creator>Gehring, J.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2022-10-10</dc:date>
<dc:identifier>doi:10.1101/2022.10.09.511501</dc:identifier>
<dc:title><![CDATA[Quantifying orthogonal barcodes for sequence census assays]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.12.511960v1?rss=1">
<title>
<![CDATA[
Border-associated macrophages mediate the neuroinflammatory response in an alpha-synuclein model of Parkinson disease 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.12.511960v1?rss=1</link>
<description><![CDATA[
Dopaminergic cell loss due to the accumulation of -syn is a core feature of PD pathogenesis. Neuroinflammation specifically induced by -syn has been shown to exacerbate neurodegeneration, yet the role of CNS resident macrophages in this process remains unclear. We found that a specific subset of CNS resident macrophages, border-associated macrophages (BAMs), play an essential role in mediating -syn related neuroinflammation due to their unique role as the antigen presenting cells necessary to initiate a CD4 T cell response. Surprisingly, the loss of MHCII antigen presentation on microglia had no effect on neuroinflammation. Furthermore, -syn expression led to an expansion in BAM numbers and a unique damage-associated activation state. Through a combinatorial approach of single-cell RNA sequencing and depletion experiments, we found that BAMs played an essential role in immune cell recruitment, infiltration, and antigen presentation. Furthermore, BAMs were identified in post-mortem PD brain in close proximity to T cells. These results point to a critical role for BAMs in mediating PD pathogenesis through their essential role in the orchestration of the -syn-mediated neuroinflammatory response.
]]></description>
<dc:creator>Schonhoff, A. M.</dc:creator>
<dc:creator>Figge, D. A.</dc:creator>
<dc:creator>Jurkuvenaite, A. J.</dc:creator>
<dc:creator>Gallups, N. J.</dc:creator>
<dc:creator>Childers, G. M.</dc:creator>
<dc:creator>Webster, J. A.</dc:creator>
<dc:creator>Standaert, D. G.</dc:creator>
<dc:creator>Goldman, J. E.</dc:creator>
<dc:creator>Harms, A. S.</dc:creator>
<dc:date>2022-10-16</dc:date>
<dc:identifier>doi:10.1101/2022.10.12.511960</dc:identifier>
<dc:title><![CDATA[Border-associated macrophages mediate the neuroinflammatory response in an alpha-synuclein model of Parkinson disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.17.512599v1?rss=1">
<title>
<![CDATA[
Transient and delay chemical master equations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.17.512599v1?rss=1</link>
<description><![CDATA[
The serial nature of reactions involved in the RNA life-cycle motivates the incorporation of delays in models of transcriptional dynamics. The models couple a bursty or switching promoter to a fairly general set of Markovian or deterministically delayed monomolecular RNA interconversion reactions with no feedback. We provide numerical solutions for the RNA copy number distributions the models induce, and solve several systems with splicing and degradation. An analysis of single-cell and single-nucleus RNA sequencing data using these models reveals that the kinetics of nuclear export do not appear to require invocation of a non-Markovian waiting time.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Yoshida, S. R.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2022-10-19</dc:date>
<dc:identifier>doi:10.1101/2022.10.17.512599</dc:identifier>
<dc:title><![CDATA[Transient and delay chemical master equations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.18.512604v1?rss=1">
<title>
<![CDATA[
MicroED structure of a protoglobin reactive carbene intermediate 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.18.512604v1?rss=1</link>
<description><![CDATA[
Microcrystal electron diffraction (MicroED) is an emerging technique which has shown great potential for describing new chemical and biological molecular structures. [1] Several important structures of small molecules, natural products and peptides have been determined using ab initio methods. [2] However, only a couple of novel protein structures have thus far been derived by MicroED. [3, 4] Taking advantage of recent technological advances including higher acceleration voltage and using a low-noise detector in counting mode, we have determined the first structure of an Aeropyrum pernix protoglobin (ApePgb) variant by MicroED using an AlphaFold2 model for phasing. The structure revealed that mutations introduced during directed evolution enhance carbene transfer activity by reorienting an alphahelix of ApePgb into a dynamic loop making the catalytic active site more readily accessible. After exposing the tiny crystals to substrate, we also trapped the reactive iron-carbenoid intermediate involved in this engineered ApePgbs new-to-nature activity, a challenging carbene transfer from a diazirine via a putative metallo-carbene. The bound structure discloses how an enlarged active site pocket stabilizes the carbene bound to the heme iron and, presumably, the transition state for formation of this key intermediate. This work demonstrates that improved MicroED technology and the advancement in protein structure prediction now enables investigation of structures that were previously beyond reach.
]]></description>
<dc:creator>Danelius, E.</dc:creator>
<dc:creator>Porter, N.</dc:creator>
<dc:creator>Unge, J.</dc:creator>
<dc:creator>Arnold, F.</dc:creator>
<dc:creator>Gonen, T.</dc:creator>
<dc:date>2022-10-18</dc:date>
<dc:identifier>doi:10.1101/2022.10.18.512604</dc:identifier>
<dc:title><![CDATA[MicroED structure of a protoglobin reactive carbene intermediate]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.19.512763v1?rss=1">
<title>
<![CDATA[
Sequencing and chromosome-scale assembly of the giant Pleurodeles waltl genome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.19.512763v1?rss=1</link>
<description><![CDATA[
The Iberian ribbed newt (Pleurodeles waltl) constitutes a central model for probing the basis of vertebrate regeneration. Here, we present the sequencing and chromosome-scale assembly of the 20.3Gb P. waltl genome, which exhibits the highest level of contiguity and completeness among giant genome assemblies. We uncover that DNA transposable elements are the major contributors to its expansion, with hAT transposons comprising a large portion of repeats. Several hATs are actively transcribed and differentially expressed during adult P. waltl limb regeneration, along with domesticated hAT transposons of the ZBED transcription factor family. Despite its size, syntenic relationships are conserved. As an example, we show the high degree of conservation of the regeneration-associated Tig1 locus with several neighbouring genes. Together, the P. waltl genome provides a fundamental resource for the study of regenerative, developmental and evolutionary principles.
]]></description>
<dc:creator>Brown, T.</dc:creator>
<dc:creator>Elewa, A.</dc:creator>
<dc:creator>Iarovenko, S.</dc:creator>
<dc:creator>Subramanian, E.</dc:creator>
<dc:creator>Joven Araus, A.</dc:creator>
<dc:creator>Petzold, A.</dc:creator>
<dc:creator>Suzuki, M.</dc:creator>
<dc:creator>Suzuki, K.-i.</dc:creator>
<dc:creator>Hayashi, T.</dc:creator>
<dc:creator>Toyoda, A.</dc:creator>
<dc:creator>Oliveira, C.</dc:creator>
<dc:creator>Osipova, E.</dc:creator>
<dc:creator>Leigh, N.</dc:creator>
<dc:creator>Simon, A.</dc:creator>
<dc:creator>Yun, M.</dc:creator>
<dc:date>2022-10-20</dc:date>
<dc:identifier>doi:10.1101/2022.10.19.512763</dc:identifier>
<dc:title><![CDATA[Sequencing and chromosome-scale assembly of the giant Pleurodeles waltl genome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.19.512933v1?rss=1">
<title>
<![CDATA[
Differential Stability of Task Variable Representations in Retrosplenial Cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.19.512933v1?rss=1</link>
<description><![CDATA[
Cortical neurons store information across different timescales, from seconds to years. Although information stability is variable across regions, it can vary within a region as well. Association areas are known to multiplex behaviorally relevant variables, but the stability of their representations is not well understood. Here, we longitudinally recorded the activity of neuronal populations in the retrosplenial cortex (RSC) during the performance of a context-choice association task. We found that the activity of neurons exhibits different levels of stability across days. Using linear classifiers, we quantified the stability of three task-relevant variables. We find that RSC representations of context and trial outcome display higher stability than motor choice, both at the single cell and population levels. Together, our findings show an important characteristic of association areas, where diverse streams of information are stored with varying levels of stability, which may balance representational reliability and flexibility according to behavioral demands.
]]></description>
<dc:creator>Franco, L. M.</dc:creator>
<dc:creator>Goard, M. J.</dc:creator>
<dc:date>2022-10-21</dc:date>
<dc:identifier>doi:10.1101/2022.10.19.512933</dc:identifier>
<dc:title><![CDATA[Differential Stability of Task Variable Representations in Retrosplenial Cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.25.513766v1?rss=1">
<title>
<![CDATA[
Genetic control of a sex-specific piRNA program 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.25.513766v1?rss=1</link>
<description><![CDATA[
Sexually dimorphic traits in morphologies are widely studied, but those in essential molecular pathways remain largely unexplored. Previous work showed substantial sex differences in Drosophila gonadal piRNAs, which guide PIWI proteins to silence selfish genetic elements thereby safeguarding fertility. However, the genetic control mechanisms of piRNA sexual dimorphism remain unknown. Here, we showed that most sex differences in the piRNA program originate from the germline rather than gonadal somatic cells. Building on this, we dissected the contribution of sex chromosome and cellular sexual identity towards the sex-specific germline piRNA program. We found that the presence of the Y chromosome is sufficient to recapitulate some aspects of the male piRNA program in a female cellular environment. Meanwhile, sexual identity controls the sexually divergent piRNA production from X-linked and autosomal loci, revealing a crucial input from sex determination into piRNA biogenesis. Sexual identity regulates piRNA biogenesis through Sxl and this effect is mediated in part through chromatin proteins Phf7 and Kipferl. Together, our work delineated the genetic control of a sex-specific piRNA program, where sex chromosome and sexual identity collectively sculpt an essential molecular trait.
]]></description>
<dc:creator>Chen, P.</dc:creator>
<dc:creator>Aravin, A. A.</dc:creator>
<dc:date>2022-10-26</dc:date>
<dc:identifier>doi:10.1101/2022.10.25.513766</dc:identifier>
<dc:title><![CDATA[Genetic control of a sex-specific piRNA program]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.28.514297v1?rss=1">
<title>
<![CDATA[
Hormone-induced enhancer assembly requires an optimal level of hormone receptor multivalent interactions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.28.514297v1?rss=1</link>
<description><![CDATA[
Transcription factors (TFs) activate enhancers to drive cell-specific gene programs in response to signals, but our understanding of enhancer assembly during signaling events is incomplete. Here, we show that Androgen Receptor (AR), a steroid hormone-regulated transcription factor, forms condensates through multivalent interactions in response to androgen signaling to orchestrate enhancer assembly. We demonstrate that the intrinsically disordered N-terminal domain (NTD) of AR drives 1,6-Hexanediol-sensitive condensate formation and that NTD deletion or aromatic residue mutation reduces AR self-association and abolishes AR transcriptional activity. AR NTD can be substituted by intrinsically disordered regions (IDRs) from selective proteins for AR condensation capacity and transactivation function. Surprisingly, strengthened AR condensation capacity caused by extending the polyQ tract within AR NTD also leads to impaired transcriptional activity without affecting AR binding on enhancers. Furthermore, either NTD deletion or polyQ extension reduces heterotypic multivalent interactions between AR and other enhancer components. These results suggest the importance of an optimal level of AR condensation in mediating AR-AR homotypic and AR-cofactor heterotypic interactions to regulate enhancer assembly in response to signals. Our study supports the notion that alteration of the fine-tuned multivalent IDR-IDR interactions might underlie AR-related human pathologies, thereby providing novel molecular insights for potential therapeutic strategies to treat prostate cancer and other AR-involved diseases by targeting AR multivalent interactions.
]]></description>
<dc:creator>Chen, L.</dc:creator>
<dc:creator>Zhang, Z.</dc:creator>
<dc:creator>Han, Q.</dc:creator>
<dc:creator>Rodrigues, L.</dc:creator>
<dc:creator>Zboril, E.</dc:creator>
<dc:creator>Adhikari, R.</dc:creator>
<dc:creator>Li, X.</dc:creator>
<dc:creator>Ko, S.-H.</dc:creator>
<dc:creator>Xue, P.</dc:creator>
<dc:creator>Smith, E.</dc:creator>
<dc:creator>Xu, K.</dc:creator>
<dc:creator>Wang, Q.</dc:creator>
<dc:creator>Huang, T. H.-M.</dc:creator>
<dc:creator>Chong, S.</dc:creator>
<dc:creator>Liu, Z.</dc:creator>
<dc:date>2022-10-30</dc:date>
<dc:identifier>doi:10.1101/2022.10.28.514297</dc:identifier>
<dc:title><![CDATA[Hormone-induced enhancer assembly requires an optimal level of hormone receptor multivalent interactions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.30.514395v1?rss=1">
<title>
<![CDATA[
Preservation of Conditioned Behavior Based on UV Light Sensitivity in Dissected Tail Halves of Planarians- a Proof by DNN 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.30.514395v1?rss=1</link>
<description><![CDATA[
Planarians are aquatic worms with powerful regenerative and memory retention abilities. This paper examines whether a dissected tail half of a Planarian (Dugesia Dorotocephala) can retain and exhibit a previously-conditioned response, possibly before the regeneration of the head and the ganglia. We conditioned intact Planarians in a Pavlovian procedure with an electric shock (ES) as the unconditioned stimulus and weak ultraviolet (UV) light as the conditioned stimulus. Then, we dissected their bodies into halves, keeping the dissected tail halves. Starting from the 2nd day after dissection, we presented the same UV light 3 times daily while video-recording the responses. The recorded responses were then classified by a DNN: a VGG16 model was pre-trained by ImageNet for extracting features from images and additionally trained with 211 responses to ES and 118 to UV light before conditioning/dissection to categorize planarians reactions into "UV-induced" or "ES-induced" reactions. The cross-validated accuracy in categorization was 83.6%. We then let the DNN analyze 99 recorded responses to UV from 20 individual conditioned tail halves. 96.8 % of their reactions were classified as "ES-induced" (against 22.0% wrongly classified as "ES-induced" for unconditioned samples under UV), indicating they have shown the "Conditioned Response" (p<3.06E-30). This provides evidence that planarians can conserve and reveal a learned response even without the head/ganglia, as it takes approximately 7 days for the head/ganglia to regenerate versus the given 2-3 days. Although similar findings have been reported repeatedly in the literature, this is the first positive evidence with automated procedures and DNN classification. The result implies the presence of a decentralized nervous structure outside of its head/ganglia that allows a tail half to retain memory and execute motion accordingly, despite their cephalization.
]]></description>
<dc:creator>Shimojo, K.</dc:creator>
<dc:creator>Shimojo, E.</dc:creator>
<dc:creator>Katsuragi, R.</dc:creator>
<dc:creator>Akashi, T.</dc:creator>
<dc:creator>Shimojo, S.</dc:creator>
<dc:date>2022-11-01</dc:date>
<dc:identifier>doi:10.1101/2022.10.30.514395</dc:identifier>
<dc:title><![CDATA[Preservation of Conditioned Behavior Based on UV Light Sensitivity in Dissected Tail Halves of Planarians- a Proof by DNN]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.11.01.514733v1?rss=1">
<title>
<![CDATA[
A microwell platform for high-throughput longitudinal phenotyping and selective retrieval of organoids 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.11.01.514733v1?rss=1</link>
<description><![CDATA[
Organoids are powerful experimental models for studying the ontogeny and progression of diseases including cancer. Organoids are conventionally cultured in bulk using an extracellular matrix mimic. However, organoids in bulk culture physically overlap, making it impossible to track the growth of individual organoids over time in high throughput. Moreover, local spatial variations in bulk matrix properties make it difficult to assess whether observed phenotypic heterogeneity between organoids results from intrinsic cell differences or microenvironment variability. Here, we developed a microwell-based method that enables high-throughput quantification of image-based parameters for organoids grown from single cells, which can be retrieved from their microwells for sequencing and molecular profiling. Coupled with a deep-learning image processing pipeline, we characterized phenotypic traits including growth rates, cellular movement, and apical-basal polarity in two CRISPR-engineered human gastric organoid models, identifying genomic changes associated with increased growth rate and changes in accessibility and expression correlated with apical-basal polarity.
]]></description>
<dc:creator>Sockell, A.</dc:creator>
<dc:creator>Wong, W.</dc:creator>
<dc:creator>Longwell, S.</dc:creator>
<dc:creator>Vu, T.</dc:creator>
<dc:creator>Karlsson, K.</dc:creator>
<dc:creator>Mokhtari, D. A.</dc:creator>
<dc:creator>Schaepe, J.</dc:creator>
<dc:creator>Lo, Y.-H.</dc:creator>
<dc:creator>Cornelius, V.</dc:creator>
<dc:creator>Kuo, C.</dc:creator>
<dc:creator>Van Valen, D. A.</dc:creator>
<dc:creator>Curtis, C.</dc:creator>
<dc:creator>Fordyce, P. M.</dc:creator>
<dc:date>2022-11-02</dc:date>
<dc:identifier>doi:10.1101/2022.11.01.514733</dc:identifier>
<dc:title><![CDATA[A microwell platform for high-throughput longitudinal phenotyping and selective retrieval of organoids]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.11.10.515371v1?rss=1">
<title>
<![CDATA[
Decoding Motor Plans Using a Closed-Loop Ultrasonic Brain-Machine Interface 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.11.10.515371v1?rss=1</link>
<description><![CDATA[
Brain-machine interfaces (BMIs) can be transformative for people living with chronic paralysis. BMIs translate brain signals into computer commands, bypassing neurological impairments and enabling people with neurological injury or disease to control computers, robots, and more with nothing but thought. State-of-the-art BMIs have already made this future a reality in limited clinical trials. However, high performance BMIs currently require highly invasive electrodes in the brain. Device degradation limits longevity to about 5 years. Their field of view is small, restricting the number, and type, of applications possible. The next generation of BMI technology should include being longer lasting, less invasive, and scalable to sense activity from large regions of the brain. Functional ultrasound neuroimaging is a recently developed technique that meets these criteria. In this present study, we demonstrate the first online, closed-loop ultrasonic brain-machine interface. We used 2 Hz real-time functional ultrasound to measure the neurovascular activity of the posterior parietal cortex in two nonhuman primates (NHPs) as they performed memory-guided movements. We streamed neural signals into a classifier to predict the intended movement direction. These predictions controlled a behavioral task in real-time while the NHP did not produce overt movements. Both NHPs quickly succeeded in controlling up to eight independent directions using the BMI. Furthermore, we present a simple method to "pretrain" the BMI using data from previous sessions. This enables the BMI to work immediately from the start of a session without acquiring extensive additional training data. This work establishes, for the first time, the feasibility of an ultrasonic BMI and prepares for future work on a next generation of minimally invasive BMIs that can restore function to patients with neurological, physical, or even psychiatric impairments.
]]></description>
<dc:creator>Griggs, W. S.</dc:creator>
<dc:creator>Norman, S. L.</dc:creator>
<dc:creator>Deffieux, T.</dc:creator>
<dc:creator>Segura, F.</dc:creator>
<dc:creator>Osmanski, B.-F.</dc:creator>
<dc:creator>Chau, G.</dc:creator>
<dc:creator>Christopoulos, V. N.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Tanter, M.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2022-11-13</dc:date>
<dc:identifier>doi:10.1101/2022.11.10.515371</dc:identifier>
<dc:title><![CDATA[Decoding Motor Plans Using a Closed-Loop Ultrasonic Brain-Machine Interface]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.11.17.516920v1?rss=1">
<title>
<![CDATA[
DNAJB6 Isoform Specific Knockdown: Therapeutic Potential for LGMDD1 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.11.17.516920v1?rss=1</link>
<description><![CDATA[
Dominant missense mutations in DNAJB6, an HSP40 co-chaperone, cause limb girdle muscular dystrophy (LGMD) D1. No treatments are currently available. Two isoforms exist, DNAJB6a and DNAJB6b, each with distinct localizations in muscle. Mutations reside in both isoforms, yet evidence suggests only DNAJB6b is responsible for disease pathogenesis. Mechanistic data supports either a toxic gain of function, a dominant negative mechanism, or a combination of both. Knockdown treatment strategies involving both isoforms carry risk as DNAJB6 knockout is embryonic lethal. We therefore developed an isoform specific knockdown approach using morpholinos. Selective reduction of each isoform was achieved in-vitro in primary mouse myotubes and human myoblasts, as well as in-vivo in mouse skeletal muscle. To assess isoform specific knockdown in LGMDD1, we created primary myotube cultures from a knock-in LGMDD1 mouse model. Using mass spectrometry, we identified an LGMDD1 protein signature related to protein homeostasis and myofibril structure. Selective reduction of DNAJB6b levels in LGMDD1 myotubes corrected much of the proteomic disease signature towards wild type levels. While additional in-vivo functional data is required, these findings suggest selective reduction of DNAJB6b may be a viable therapeutic target for LGMDD1.
]]></description>
<dc:creator>Findlay, A. R.</dc:creator>
<dc:creator>Paing, M. M.</dc:creator>
<dc:creator>Daw, J. A.</dc:creator>
<dc:creator>Bengoechea, R.</dc:creator>
<dc:creator>Pittman, S. K.</dc:creator>
<dc:creator>Li, S.</dc:creator>
<dc:creator>Wang, F.</dc:creator>
<dc:creator>Miller, T. M.</dc:creator>
<dc:creator>True, H. L.</dc:creator>
<dc:creator>Weihl, C. C.</dc:creator>
<dc:date>2022-11-17</dc:date>
<dc:identifier>doi:10.1101/2022.11.17.516920</dc:identifier>
<dc:title><![CDATA[DNAJB6 Isoform Specific Knockdown: Therapeutic Potential for LGMDD1]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.11.17.516988v1?rss=1">
<title>
<![CDATA[
Addressable and adaptable intercellular communication via DNA messaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.11.17.516988v1?rss=1</link>
<description><![CDATA[
Engineered consortia are a major research focus for synthetic biologists because they can implement sophisticated behaviors inaccessible to single-strain systems. However, this functional capacity is constrained by their constituent strains ability to engage in complex communication. DNA messaging, by enabling information-rich channel-decoupled communication, is a promising candidate architecture for implementing complex communication. But its major advantage, its messages dynamic mutability, is still unexplored. We develop a framework for addressable and adaptable DNA messaging that leverages all three of these advantages and implement it in a plasmid conjugation-based communication channel. Our system can bias the transfer of messages to targeted receiver strains by 100-to 1000-fold, and their recipient lists can be dynamically updated in situ to control the flow of information through the population. This work lays the foundation for future developments that further utilize the unique advantages of DNA messaging to engineer previously-inaccessible levels of complexity into biological systems.
]]></description>
<dc:creator>Marken, J. P.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2022-11-18</dc:date>
<dc:identifier>doi:10.1101/2022.11.17.516988</dc:identifier>
<dc:title><![CDATA[Addressable and adaptable intercellular communication via DNA messaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.11.18.516445v1?rss=1">
<title>
<![CDATA[
Distinct super-enhancer elements differentially control Il2ra gene expression in a cell-type specific fashion 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.11.18.516445v1?rss=1</link>
<description><![CDATA[
The IL-2 receptor -chain (IL-2R/CD25) is constitutively expressed on DN2/DN3 thymocytes and Treg cells but induced by IL-2 on mature T and NK cells. Il2ra expression is regulated by a super-enhancer extensively bound by STAT5 in mature T cells. Here, we demonstrate that STAT5 cooperates with Notch to induce/maintain Il2ra/CD25 expression in DN2/DN3 cells. Moreover, we systematically investigated CD25 regulation using a series of mice with deletions spanning STAT5 binding elements. Deleting the upstream super-enhancer region mainly affected constitutive CD25 expression on DN2/DN3 thymocytes and Tregs, whereas deleting an intronic region primarily decreased IL-2-induced CD25 on peripheral T and NK cells. Thus, distinct elements preferentially control constitutive versus inducible expression in a cell-type-specific manner, with the MED1 coactivator co-localizing with specific STAT5 binding sites. Moreover, the intronic region was a dominant element whose deletion altered the structure throughout the super-enhancer in mature T cells. These results demonstrate differential functions for distinct super-enhancer elements, thereby indicating ways to manipulate CD25 expression in a cell-type specific fashion.
]]></description>
<dc:creator>Spolski, R.</dc:creator>
<dc:creator>Li, P.</dc:creator>
<dc:creator>Chandra, V.</dc:creator>
<dc:creator>Shin, B.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Oh, J.</dc:creator>
<dc:creator>Ren, M.</dc:creator>
<dc:creator>Enomoto, Y.</dc:creator>
<dc:creator>West, E. E.</dc:creator>
<dc:creator>Christensen, S.</dc:creator>
<dc:creator>Wan, E. C. K.</dc:creator>
<dc:creator>Ge, M.</dc:creator>
<dc:creator>Lin, J.-X.</dc:creator>
<dc:creator>Vijayanand, P.</dc:creator>
<dc:creator>Rothenberg, E. V.</dc:creator>
<dc:creator>Leonard, W. J.</dc:creator>
<dc:date>2022-11-18</dc:date>
<dc:identifier>doi:10.1101/2022.11.18.516445</dc:identifier>
<dc:title><![CDATA[Distinct super-enhancer elements differentially control Il2ra gene expression in a cell-type specific fashion]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.11.18.517146v1?rss=1">
<title>
<![CDATA[
Runx factors launch T-cell and innate lymphoid programs via direct and gene network-based mechanisms 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.11.18.517146v1?rss=1</link>
<description><![CDATA[
Runx factors are essential for lineage specification of various hematopoietic cells, including T lymphocytes. However, they regulate context-specific genes and occupy distinct genomic regions in different cell types. Here, we show that dynamic Runx binding shifts in early T-cell development are mostly not restricted by local chromatin state but regulated by Runx dosage and functional partners. Runx co-factors compete to recruit a limited pool of Runx factors in early T-progenitors, and a modest increase in Runx protein availability at pre-commitment stages causes premature Runx occupancy at post-commitment binding sites. This results in striking T-lineage developmental acceleration by selectively activating T-identity and innate lymphoid cell programs. These are collectively regulated by Runx together with other, Runx-induced transcription factors that co-occupy Runx target genes and propagate gene network changes.
]]></description>
<dc:creator>Shin, B.</dc:creator>
<dc:creator>Zhou, W.</dc:creator>
<dc:creator>Wang, J.</dc:creator>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>Rothenberg, E. V.</dc:creator>
<dc:date>2022-11-19</dc:date>
<dc:identifier>doi:10.1101/2022.11.18.517146</dc:identifier>
<dc:title><![CDATA[Runx factors launch T-cell and innate lymphoid programs via direct and gene network-based mechanisms]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.11.23.517749v1?rss=1">
<title>
<![CDATA[
Physiological adaptation of sulfate reducing bacteria in syntrophic partnership with anaerobic methanotrophic archaea 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.11.23.517749v1?rss=1</link>
<description><![CDATA[
Sulfate-coupled anaerobic oxidation of methane (AOM) is performed by multicellular consortia of anaerobic methanotrophic archaea (ANME) in obligate syntrophic partnership with sulfate-reducing bacteria (SRB). Diverse ANME and SRB clades co-associate but the physiological basis for their adaptation and diversification is not well understood. In this work, we explore the metabolic adaptation of four syntrophic SRB clades (HotSeep-1, Seep-SRB2, Seep-SRB1a and Seep-SRB1g) from a phylogenomics perspective, tracing the evolution of conserved proteins in the syntrophic SRB clades, and comparing the genomes of syntrophic SRB to their nearest evolutionary neighbors in the phylum Desulfobacterota. We note several examples of gain, loss or biochemical adaptation of proteins within pathways involved in extracellular electron transfer, electron transport chain, nutrient sharing, biofilm formation and cell adhesion. We demonstrate that the metabolic adaptations in each of these syntrophic clades are unique, suggesting that they have independently evolved, converging to a syntrophic partnership with ANME. Within the clades we also investigated the specialization of different syntrophic SRB species to partnerships with different ANME clades, using metagenomic sequences obtained from ANME and SRB partners in individual consortia after fluorescent-sorting of cell aggregates from anaerobic sediments. In one instance of metabolic adaptation to different partnerships, we show that Seep-SRB1a partners of ANME-2c appear to lack nutritional auxotrophies, while the related Seep-SRB1a partners of a different methanotrophic archaeal lineage, ANME-2a, are missing the cobalamin synthesis pathway, suggesting that the Seep-SRB1a partners of ANME-2a may have a nutritional dependence on its partner. Together, our paired genomic analysis of AOM consortia highlights the specific adaptation and diversification of syntrophic SRB clades linked to their associated ANME lineages.
]]></description>
<dc:creator>Murali, R.</dc:creator>
<dc:creator>Yu, H.</dc:creator>
<dc:creator>Speth, D.</dc:creator>
<dc:creator>Wu, F.</dc:creator>
<dc:creator>Metcalfe, K. S.</dc:creator>
<dc:creator>Cremiere, A.</dc:creator>
<dc:creator>Laso-Perez, R.</dc:creator>
<dc:creator>Malmstrom, R.</dc:creator>
<dc:creator>Goudeau, D.</dc:creator>
<dc:creator>Woyke, T.</dc:creator>
<dc:creator>Hatzenpichler, R.</dc:creator>
<dc:creator>Chadwick, G.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2022-11-23</dc:date>
<dc:identifier>doi:10.1101/2022.11.23.517749</dc:identifier>
<dc:title><![CDATA[Physiological adaptation of sulfate reducing bacteria in syntrophic partnership with anaerobic methanotrophic archaea]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.11.29.518402v1?rss=1">
<title>
<![CDATA[
A selectivity filter in the EMC limits protein mislocalization to the ER 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.11.29.518402v1?rss=1</link>
<description><![CDATA[
Tail anchored proteins (TAs) play essential roles at both the ER and mitochondria, and their accurate localization is critical to proteostasis. Biophysical similarities lead to mistargeting of mitochondrial TAs to the ER, where they are delivered to the ER membrane protein complex (EMC). We showed that the EMC directly contributes to sorting fidelity of mitochondrial TAs and multipass substrates that contain positively charged soluble domains. Leveraging an improved structural model of the human EMC, we used mutagenesis and site-specific crosslinking to map the path of a TA from its cytosolic capture by methionine-rich loops to its membrane insertion through a hydrophilic vestibule. Positively charged residues at the entrance to the vestibule function as a selectivity filter that uses charge-repulsion to reject mitochondrial TAs. Substrate discrimination by the EMC provides a biochemical explanation for one role of charge in TA sorting and protects compartment identity by limiting protein misinsertion.
]]></description>
<dc:creator>Pleiner, T.</dc:creator>
<dc:creator>Hazu, M.</dc:creator>
<dc:creator>Tomaleri, G. P.</dc:creator>
<dc:creator>Nguyen, V. N.</dc:creator>
<dc:creator>Januszyk, K.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:date>2022-12-01</dc:date>
<dc:identifier>doi:10.1101/2022.11.29.518402</dc:identifier>
<dc:title><![CDATA[A selectivity filter in the EMC limits protein mislocalization to the ER]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.02.518787v1?rss=1">
<title>
<![CDATA[
Annotation-agnostic discovery of associations between novel gene isoforms and phenotypes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.02.518787v1?rss=1</link>
<description><![CDATA[
We present a novel method for associating phenotypes with RNA expression, that can identify expression associations resulting from a wide variety of underlying transcriptional and post-transcriptional events, without relying on annotations of these events. We show that we can reliably detect, de novo, phenotypically relevant transcriptional structures
]]></description>
<dc:creator>Eldjarn Hjörleifsson, K.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Melsted, P.</dc:creator>
<dc:date>2022-12-02</dc:date>
<dc:identifier>doi:10.1101/2022.12.02.518787</dc:identifier>
<dc:title><![CDATA[Annotation-agnostic discovery of associations between novel gene isoforms and phenotypes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.02.518832v1?rss=1">
<title>
<![CDATA[
Accurate quantification of single-nucleus and single-cell RNA-seq transcripts 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.02.518832v1?rss=1</link>
<description><![CDATA[
In single-cell and single-nucleus RNA sequencing, the coexistence of nascent (unprocessed) and mature (processed) mRNA poses challenges in accurate read mapping and the interpretation of count matrices. The traditional transcriptome reference, defining the  region of interest in bulk RNA-seq, restricts its focus to mature mRNA transcripts. This restriction leads to two problems: reads originating outside of the  region of interest are prone to mismapping within this region, and additionally, such external reads cannot be matched to specific transcript targets. Expanding the  region of interest to encompass both nascent and mature mRNA transcript targets provides a more comprehensive framework for RNA-seq analysis. Here, we introduce the concept of distinguishing flanking k-mers (DFKs) to improve mapping of sequencing reads. We have developed an algorithm to identify DFKs, which serve as a sophisticated  background filter, enhancing the accuracy of mRNA quantification. This dual strategy of an expanded region of interest coupled with the use of DFKs enhances the precision in quantifying both mature and nascent mRNA molecules, as well as in delineating reads of ambiguous status.
]]></description>
<dc:creator>Eldjarn Hjörleifsson, K.</dc:creator>
<dc:creator>Sullivan, D. K.</dc:creator>
<dc:creator>Holley, G.</dc:creator>
<dc:creator>Melsted, P.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2022-12-02</dc:date>
<dc:identifier>doi:10.1101/2022.12.02.518832</dc:identifier>
<dc:title><![CDATA[Accurate quantification of single-nucleus and single-cell RNA-seq transcripts]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.05.519224v1?rss=1">
<title>
<![CDATA[
The role of a population of descending neurons in the optomotor response in flying Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.05.519224v1?rss=1</link>
<description><![CDATA[
To maintain stable flight, animals continuously perform trimming adjustments to compensate for internal and external perturbations. Whereas animals use many different sensory modalities to detect such perturbations, insects rely extensively on optic flow to modify their motor output and remain on course. We studied this behavior in the fruit fly, Drosophila melanogaster, by exploiting the optomotor response, a robust reflex in which an animal steers so as to minimize the magnitude of rotatory optic flow it perceives. Whereas the behavioral and algorithmic structure of the optomotor response has been studied in great detail, its neural implementation is not well-understood. In this paper, we present findings implicating a group of nearly homomorphic descending neurons, the DNg02s, as a core component for the optomotor response in flying Drosophila. Prior work on these cells suggested that they regulate the mechanical power to the flight system, presumably via connections to asynchronous flight motor neurons in the ventral nerve cord. When we chronically inactivated these cells, we observed that the magnitude of the optomotor response was diminished in proportion to the number of cells silenced, suggesting that the cells also regulate bilaterally asymmetric steering responses via population coding. During an optomotor response, flies coordinate changes in wing motion with movements of their head, abdomen, and hind legs, which are also diminished when the DNg02 cells are silenced. Using two-photon functional imaging, we show that the DNg02 cells respond most strongly to patterns of horizontal motion and that neuronal activity is closely correlated to motor output. However, unilateral optogenetic activation of DNg02 neurons does not elicit the asymmetric changes in wing motion characteristic of the optomotor response to a visual stimulus, but rather generates bilaterally symmetric increases in wingbeat amplitude. We interpret our experiments to suggest that flight maneuvers in flies require a more nuanced coordination of power muscles and steering muscles than previously appreciated, and that the physical flight apparatus of a fly might permit mechanical power to be distributed differentially between the two wings. Thus, whereas our experiments identify the DNg02 cells as a critical component of the optomotor reflex, our results suggest that other classes of descending cells targeting the steering muscle motor neurons are also required for the behavior.
]]></description>
<dc:creator>Palmer, E. H.</dc:creator>
<dc:creator>Omoto, J. J.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:date>2022-12-06</dc:date>
<dc:identifier>doi:10.1101/2022.12.05.519224</dc:identifier>
<dc:title><![CDATA[The role of a population of descending neurons in the optomotor response in flying Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.06.519381v1?rss=1">
<title>
<![CDATA[
The Role of 1-O-Acylceramide NP in Structural Organization and Permeability of the Stratum Corneum Lipid Matrix 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.06.519381v1?rss=1</link>
<description><![CDATA[
The extracellular lipid matrix in the stratum corneum (SC) is crucial for generating a skin barrier (permeability) function. The lipid matrix contains three major components; ceramides, cholesterol, and free fatty acids. The broad diversity of ceramides depends on their molecular structures (e.g., hydroxylations and chain lengths) and plays a critical role in maintaining the structural integrity of the lipid matrix. Although recent studies identified a new subclass of ceramide, 1-O-acylceramide NP (CerENP), its precise role in the lipid matrix of SC is still elusive. Herein, we investigate the role of CerENP on the structure and permeability of the SC by molecular dynamics simulations. Our results suggest that the CerENP molecules induce a denser lipid matrix in the lateral dimension in the long periodicity phase model with a bilayer-slab- bilayer structure. Moreover, ethanol permeability analysis indicates that CerENP can suppress molecular permeability through the lipid matrix. This study provides insight into the role of a new subclass of ceramide in the SC, which can lead to our better understanding of skin organization and disease-related barrier dysfunction.
]]></description>
<dc:creator>Yang, M. Y.</dc:creator>
<dc:creator>Lee, E. O.</dc:creator>
<dc:creator>Park, C. S.</dc:creator>
<dc:creator>Nam, Y. S.</dc:creator>
<dc:date>2022-12-10</dc:date>
<dc:identifier>doi:10.1101/2022.12.06.519381</dc:identifier>
<dc:title><![CDATA[The Role of 1-O-Acylceramide NP in Structural Organization and Permeability of the Stratum Corneum Lipid Matrix]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.12.520188v1?rss=1">
<title>
<![CDATA[
Characterizing habit learning in the human brain at the individual and group levels: a multi-modal MRI study 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.12.520188v1?rss=1</link>
<description><![CDATA[
The dual-process theory of action control postulates that there are two competitive and complementary mechanisms that control our behavior: a goal-directed system that executes deliberate actions, explicitly aimed toward a particular outcome, and a habitual system that autonomously execute well-learned actions, typically following an encounter with a previously associated cue. In line with dual-process theory, animal studies have provided convincing evidence for dissociable neural mechanisms, mainly manifested in cortico-striatal regions, involved in goal-directed and habitual action control. While substantial progress has been made in characterizing the neural mechanism underlying habit learning in animals, we still lack knowledge on how habits are formed and maintained in the human brain. Thus far only one study, conducted more than a decade ago by Tricomi et al. (2009), has been able to induce habitual behavior in humans via extensive training. This study also implicated the posterior putamen in the process, using functional magnetic resonance imaging (fMRI). However, recent attempts to replicate the behavioral results of this study were not successful. This leaves the research of human habits, and particularly the research of their formation through extensive repetition, as well as their neural basis, limited and far behind the animal research in the field. This motivated us to (1) attempt to replicate the behavioral and imaging main findings of Tricomi et al., (2) identify further functional and microstructural neural modifications associated with habit formation and manifestation, and (3) investigate the relationships between functional and structural plasticity and individual differences in habit expression. To this end, in this registered report we used Tricomi et al.s free-operant task along with multi-modal MRI methods in a well-powered sample (n=123). In this task participants sensitivity to outcome devaluation (an index of goal-directed/habitual action control) is tested following either short or extensive training. In contrast to our hypothesis, we were not able to demonstrate habit formation as a function of training duration nor were we able to relate any functional or microstructural plasticity in the putamen with individual habit expression. We found that a pattern of increased activations in the left head of caudate that re-occurred across each days training is associated with goal directed behavior and that increased processing of devalued cues in low-level visual regions was indicative of goal-directed behavior (and vice versa). In a follow-up exploratory analysis comparing habitual and goal-directed subgroups within each experimental group, we found that elevated activations in frontoparietal regions during early stages of training, as well as increased reactivity towards still-valued cues in somatosensory and superior parietal regions were found in individuals that were more inclined to perform goal-directed behavior (compared with more habitual individuals). Taken together, regions commonly implicated in goal-directed behavior were most predictive of individual habit expression. Finally, we also found that differential patterns of training-related microstructural plasticity, as measured with diffusion MRI, in midbrain dopaminergic regions were associated with habit expression. This work provides new insights into the neural dynamics involved in individual habit formation/expression and encourages the development and testing of new, more sensitive, procedures for experimental habit induction in humans.
]]></description>
<dc:creator>Gera, R.</dc:creator>
<dc:creator>Bar Or, M.</dc:creator>
<dc:creator>Tavor, I.</dc:creator>
<dc:creator>Roll, D.</dc:creator>
<dc:creator>Cockburn, J.</dc:creator>
<dc:creator>Barak, S.</dc:creator>
<dc:creator>Tricomi, E.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:creator>Schonberg, T.</dc:creator>
<dc:date>2022-12-13</dc:date>
<dc:identifier>doi:10.1101/2022.12.12.520188</dc:identifier>
<dc:title><![CDATA[Characterizing habit learning in the human brain at the individual and group levels: a multi-modal MRI study]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.15.519123v1?rss=1">
<title>
<![CDATA[
Cell-specific occupancy dynamics between the pioneer-like factor Opa/ZIC and Ocelliles/OTX regulate early head development in embryos 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.15.519123v1?rss=1</link>
<description><![CDATA[
During development, embryonic patterning systems direct a set of initially uncommitted pluripotent cells to differentiate into a variety of cell types and tissues. A core network of transcription factors, such as Zelda/POU5F1, Odd-paired (Opa)/ZIC and Ocelliless (Oc)/OTX, are conserved across animals. While Opa is essential for a second wave of zygotic activation after Zelda, it is unclear whether Opa drives head cell specification past gastrulation onset, in the Drosophila embryo. Our hypothesis is that Opa and Oc are interacting with distinct cis-regulatory regions for shaping cell fates in the embryonic head. Using super-resolution microscopy and epigenomic meta-analysis of single cell RNAseq datasets we find that opas and ocs overlapping expression domains are dynamic in the head region, with both factors being simultaneously transcribed at the blastula stage. However, analysis of single-embryo RNAseq data reveals a subgroup of Opa-bound genes to be Opa-independent in the cellularized embryo. Interrogation of these genes against Oc ChIPseq combined with in situ data, suggests that Opa is competing with Oc for the regulation of a subgroup of genes later in gastrulation. Specifically, we find that Oc binds to late, head-specific enhancers independently and activates them in a head-specific wave of zygotic transcription, suggesting distinct roles for Oc in the blastula and gastrula stages.
]]></description>
<dc:creator>Fenelon, K.</dc:creator>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>Borad, P.</dc:creator>
<dc:creator>Abbasi, S.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Koromila, T.</dc:creator>
<dc:date>2022-12-16</dc:date>
<dc:identifier>doi:10.1101/2022.12.15.519123</dc:identifier>
<dc:title><![CDATA[Cell-specific occupancy dynamics between the pioneer-like factor Opa/ZIC and Ocelliles/OTX regulate early head development in embryos]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.15.520316v1?rss=1">
<title>
<![CDATA[
Towards Cloud-Native, Machine Learning Based Detection of Crop Disease with Imaging Spectroscopy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.15.520316v1?rss=1</link>
<description><![CDATA[
Developing actionable early detection and warning systems for agricultural stakeholders is crucial to reduce the annual $200B USD losses and environmental impacts associated with crop diseases. Agricultural stakeholders primarily rely on labor-intensive, expensive scouting and molecular testing to detect disease. Spectroscopic imagery (SI) can improve plant disease management by offering decision-makers accurate risk maps derived from Machine Learning (ML) models. However, training and deploying ML requires significant computation and storage capabilities. This challenge will become even greater as global scale data from the forthcoming Surface Biology & Geology (SBG) satellite becomes available. This work presents a cloud-hosted architecture to streamline plant disease detection with SI from NASAs AVIRIS-NG platform, using grapevine leafroll associated virus complex 3 (GLRaV-3) as a model system. Here, we showcase a pipeline for processing SI to produce plant disease detection models and demonstrate that the underlying principles of a cloud-based disease detection system easily accommodate model improvements and shifting data modalities. Our goal is to make the insights derived from SI available to agricultural stakeholders via a platform designed with their needs and values in mind. The key outcome of this work is an innovative, responsive system foundation that can empower agricultural stakeholders to make data-driven plant disease management decisions, while serving as a framework for others pursuing use-inspired application development for agriculture to follow that ensures social impact and reproducibility while preserving stakeholder privacy.

Key PointsO_LICloud-based plant disease detection system, easily accommodates newly developed and/or improved models, as well as diverse data modalities.
C_LIO_LIEmpower agricultural stakeholders to use hyperspectral data for decision support while preserving stakeholder data privacy.
C_LIO_LIOutline framework for researchers interested in designing geospatial/remote sensing applications for agricultural stakeholders to follow.
C_LI
]]></description>
<dc:creator>Rubambiza, G.</dc:creator>
<dc:creator>Romero Galvan, F. E.</dc:creator>
<dc:creator>Pavlick, R. P.</dc:creator>
<dc:creator>Weatherspoon, H.</dc:creator>
<dc:creator>Gold, K.</dc:creator>
<dc:date>2022-12-19</dc:date>
<dc:identifier>doi:10.1101/2022.12.15.520316</dc:identifier>
<dc:title><![CDATA[Towards Cloud-Native, Machine Learning Based Detection of Crop Disease with Imaging Spectroscopy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.15.520539v1?rss=1">
<title>
<![CDATA[
Zn2+ potentiation of OTOP proton channels identifies structural elements of the gating apparatus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.15.520539v1?rss=1</link>
<description><![CDATA[
Otopetrin proteins (OTOPs) form proton-selective ion channels that are expressed in diverse cell types where they may mediate detection of acids or regulation of pH. In vertebrates there are three family members: OTOP1 is required for formation of otoconia in the vesibular system and it forms the receptor for sour taste, while the functions of OTOP2, and OTOP3 are not yet known. Importantly, the gating mechanisms of any of the OTOP channels are not well-understood, and until recently, it was not even known if the channels were gated. Here we show that Zn2+, as well as other transition metals including copper (Cu2+), potently activate murine OTOP3. Zn2+ pre-exposure increases the magnitude of OTOP3 currents to a subsequent acid stimulus by as much as 10-fold. In contrast, OTOP2 currents are insensitive to potentiation by Zn2+. Swapping the extracellular tm 11-12 linker between OTOP3 and OTOP2 was sufficient to eliminate Zn2+ potentiation of OTOP3 and confer Zn2+ potentiation on OTOP2. We also show that H531 within the tm 11-12 linker is essential for potentiation of OTOP3 by Zn2+, likely by forming part of its binding site. Kinetic modeling of the data is consistent with Zn2+ stabilizing the open state of the channel, possibly competing with H+ for activation of the channels. These results establish the tm 11-12 linker as part of the gating apparatus of OTOP channels and a target for drug discovery. Zinc is an essential micronutrient and its regulation of OTOP channels will undoubtedly have important physiological sequelae.

Significance StatementA family of proton-activated H+ ion channels was recently identified that includes the sour receptor OTOP1. Here we show that members of the OTOP channel family are differentially sensitive to Zn2+, which strongly activates OTOP3 but not OTOP2. By studying chimeric channels, we identify structural elements in the extracellular linker between transmembrane domains 11-12 that are necessary and sufficient for Zn2+ activation of OTOP channels. In addition to the taste system, OTOP channels play important roles in biomineralization in both vertebrate and invertebrates and are expressed in the digestive tract where their expression is a predictor of cancer prognosis. Our identification of the tm 11-12 linker as part of the gating apparatus makes it a promising target for pharmaceutical discovery.
]]></description>
<dc:creator>Teng, B.</dc:creator>
<dc:creator>Kaplan, J.</dc:creator>
<dc:creator>Liang, Z.</dc:creator>
<dc:creator>Goldschen-Ohm, M. P.</dc:creator>
<dc:creator>Liman, E.</dc:creator>
<dc:date>2022-12-18</dc:date>
<dc:identifier>doi:10.1101/2022.12.15.520539</dc:identifier>
<dc:title><![CDATA[Zn2+ potentiation of OTOP proton channels identifies structural elements of the gating apparatus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.18.520715v1?rss=1">
<title>
<![CDATA[
An auto-release mechanism for HMCES-DNA-protein crosslinks 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.18.520715v1?rss=1</link>
<description><![CDATA[
The conserved protein HMCES crosslinks to abasic (AP) sites in ssDNA to prevent strand scission and the formation of toxic dsDNA breaks during replication. Here, we report a non-proteolytic release mechanism for HMCES-DNA-protein crosslinks (DPCs), which is regulated by DNA context. In ssDNA and at ssDNA-dsDNA junctions, HMCES-DPCs are stable, which efficiently protects AP sites against spontaneous incisions and cleavage by APE1 endonuclease. In contrast, HMCES-DPCs are quickly released in dsDNA, allowing APE1 to initiate downstream repair. Mechanistically, we show that release is governed by two components. First, a conserved glutamate residue within HMCES active site catalyses reversal of the crosslink. Second, affinity to the underlying DNA structure determines whether HMCES re-crosslinks or dissociates. Our study reveals that the protective role of HMCES-DPCs involves their controlled release upon bypass by replication forks, which restricts DPC formation to a necessary minimum.
]]></description>
<dc:creator>Donsbach, M.</dc:creator>
<dc:creator>Dürauer, S.</dc:creator>
<dc:creator>Nguyen, K. T.</dc:creator>
<dc:creator>Grünert, F.</dc:creator>
<dc:creator>Yaneva, D.</dc:creator>
<dc:creator>Semlow, D.</dc:creator>
<dc:creator>Stingele, J.</dc:creator>
<dc:date>2022-12-19</dc:date>
<dc:identifier>doi:10.1101/2022.12.18.520715</dc:identifier>
<dc:title><![CDATA[An auto-release mechanism for HMCES-DNA-protein crosslinks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.26.521940v1?rss=1">
<title>
<![CDATA[
ESCRT recruitment to mRNA-encoded SARS-CoV-2 spike induces virus-like particles and enhanced antibody responses 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.26.521940v1?rss=1</link>
<description><![CDATA[
Prime-boost regimens for COVID-19 vaccines elicit poor antibody responses against Omicron-based variants and employ frequent boosters to maintain antibody levels. We present a natural infection-mimicking technology that combines features of mRNA- and protein nanoparticle-based vaccines through encoding self-assembling enveloped virus-like particles (eVLPs). eVLP assembly is achieved by inserting an ESCRT- and ALIX-binding region (EABR) into the SARS-CoV-2 spike cytoplasmic tail, which recruits ESCRT proteins to induce eVLP budding from cells. Purified spike-EABR eVLPs presented densely-arrayed spikes and elicited potent antibody responses in mice. Two immunizations with mRNA-LNP encoding spike-EABR elicited potent CD8+ T-cell responses and superior neutralizing antibody responses against original and variant SARS-CoV-2 compared to conventional spike-encoding mRNA-LNP and purified spike-EABR eVLPs, improving neutralizing titers >10-fold against Omicron-based variants for three months post-boost. Thus, EABR technology enhances potency and breadth of vaccine-induced responses through antigen presentation on cell surfaces and eVLPs, enabling longer-lasting protection against SARS-CoV-2 and other viruses.
]]></description>
<dc:creator>Hoffmann, M. A.</dc:creator>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Huey-Tubman, K. E.</dc:creator>
<dc:creator>Cohen, A. A.</dc:creator>
<dc:creator>Gnanapragasam, P. N.</dc:creator>
<dc:creator>Nakatomi, L. M.</dc:creator>
<dc:creator>Storm, K. N.</dc:creator>
<dc:creator>Moon, W. J.</dc:creator>
<dc:creator>Lin, P. J.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2022-12-27</dc:date>
<dc:identifier>doi:10.1101/2022.12.26.521940</dc:identifier>
<dc:title><![CDATA[ESCRT recruitment to mRNA-encoded SARS-CoV-2 spike induces virus-like particles and enhanced antibody responses]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.28.522046v1?rss=1">
<title>
<![CDATA[
Data-driven model of glycolysis identifies the role of allostery in maintaining ATP homeostasis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.28.522046v1?rss=1</link>
<description><![CDATA[
Glycolysis is a conserved metabolic pathway that produces ATP and biosynthetic precursors. Here, we use mathematical modeling to investigate how the control of mammalian glycolytic enzymes through allostery and mass action accomplishes various tasks of ATP homeostasis, such as controlling the rate of ATP production, maintaining high and stable ATP levels, and ensuring that ATP hydrolysis generates a net excess of energy. Our model uses data-derived enzyme rate equations, recapitulates the key tasks of glycolytic ATP homeostasis, and accurately predicts absolute concentrations of glycolytic intermediates and isotope tracing kinetics in live cells. We find that allosteric regulation of hexokinase (HK) and phosphofructokinase (PFK) by ATP, ADP, inorganic phosphate and glucose-6-phosphate (G6P), the surplus of lower glycolysis enzymes, and a large non-adenine phosphate pool are essential to robustly maintain high ATP levels and to prevent uncontrolled accumulation of phosphorylated intermediates of upper glycolysis. Meanwhile, mass action alone is sufficient to control ATP production rate and maintain high energy of ATP hydrolysis. Our results suggest a revision of the textbook view that the function of allosteric regulation of HK, PFK and PK is to control the net flux through glycolysis in response to variable ATP demand.
]]></description>
<dc:creator>Choe, M.</dc:creator>
<dc:creator>Einav, T.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:creator>Titov, D. V.</dc:creator>
<dc:date>2022-12-30</dc:date>
<dc:identifier>doi:10.1101/2022.12.28.522046</dc:identifier>
<dc:title><![CDATA[Data-driven model of glycolysis identifies the role of allostery in maintaining ATP homeostasis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.04.522632v1?rss=1">
<title>
<![CDATA[
3D genome organization around nuclear speckles drives mRNA splicing efficiency 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.04.522632v1?rss=1</link>
<description><![CDATA[
The nucleus is highly organized such that factors involved in transcription and processing of distinct classes of RNA are organized within specific nuclear bodies. One such nuclear body is the nuclear speckle, which is defined by high concentrations of protein and non-coding RNA regulators of pre-mRNA splicing. What functional role, if any, speckles might play in the process of mRNA splicing remains unknown. Here we show that genes localized near nuclear speckles display higher spliceosome concentrations, increased spliceosome binding to their pre-mRNAs, and higher co-transcriptional splicing levels relative to genes that are located farther from nuclear speckles. We show that directed recruitment of a pre-mRNA to nuclear speckles is sufficient to drive increased mRNA splicing levels. Finally, we show that gene organization around nuclear speckles is highly dynamic with differential localization between cell types corresponding to differences in Pol II occupancy. Together, our results integrate the longstanding observations of nuclear speckles with the biochemistry of mRNA splicing and demonstrate a critical role for dynamic 3D spatial organization of genomic DNA in driving spliceosome concentrations and controlling the efficiency of mRNA splicing
]]></description>
<dc:creator>Bhat, P.</dc:creator>
<dc:creator>Chow, A.</dc:creator>
<dc:creator>Emert, B.</dc:creator>
<dc:creator>Ettlin, O.</dc:creator>
<dc:creator>Quinodoz, S. A.</dc:creator>
<dc:creator>Takei, Y.</dc:creator>
<dc:creator>Huang, W.</dc:creator>
<dc:creator>Blanco, M. R.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:date>2023-01-04</dc:date>
<dc:identifier>doi:10.1101/2023.01.04.522632</dc:identifier>
<dc:title><![CDATA[3D genome organization around nuclear speckles drives mRNA splicing efficiency]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.07.522790v1?rss=1">
<title>
<![CDATA[
Cytokinins regulate spatially-specific ethylene production to control root growth in Arabidopsis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.07.522790v1?rss=1</link>
<description><![CDATA[
The two principal growth regulators cytokinins and ethylene are known to interact in the regulation of plant growth. However, information about underlying molecular mechanism and positional specificity of the cytokinin/ethylene crosstalk in root growth control is scarce. We have identified spatial specificity of cytokinin-regulated root elongation and root apical meristem (RAM) size, both of which we demonstrate to be ethylene biosynthesis-dependent. Upregulation of the cytokinin biosynthetic gene ISOPENTENYLTRANSFERASE (IPT) in proximal and peripheral tissues leads to both root and RAM shortening. In contrast, IPT activation in distal and inner tissues reduces RAM size while leaving the root length comparable to mock-treated controls. We show that cytokinins regulate two steps specific to ethylene biosynthesis, the production of ACC by ACC SYNTHASEs (ACSs), and its conversion to ethylene by ACC OXIDASEs (ACOs). We describe cytokinin- and ethylene-specific regulation controlling the activity of ACSs and ACOs that are spatially discrete along both proximo/distal and radial root axes. Using direct ethylene measurements, we identify ACO2, ACO3 and ACO4 as being responsible for ethylene biosynthesis and the ethylene-regulated root and RAM shortening in cytokinin-treated Arabidopsis. Finally, we describe the tight cooperation between cytokinin and ethylene signaling in cytokinin-induced, ethylene-regulated control of ACO4 due to the direct interaction between ARABIDOPSIS RESPONSE REGULATOR 2 (ARR2), a member of the multistep phosphorelay cascade and the C-terminal portion of ETHYLENE INSENSITIVE 2 (EIN2-C), a key regulator of canonical ethylene signaling.
]]></description>
<dc:creator>Yamoune, A.</dc:creator>
<dc:creator>Zdarska, M.</dc:creator>
<dc:creator>Depaepe, T.</dc:creator>
<dc:creator>Korytarova, A.</dc:creator>
<dc:creator>Skalak, J.</dc:creator>
<dc:creator>Berendzen, K. W.</dc:creator>
<dc:creator>Mira-Rodado, V.</dc:creator>
<dc:creator>Tarr, P.</dc:creator>
<dc:creator>Spackova, E.</dc:creator>
<dc:creator>Badurova, L.</dc:creator>
<dc:creator>Parizkova, B.</dc:creator>
<dc:creator>Franczyk, A.</dc:creator>
<dc:creator>Kovacova, I.</dc:creator>
<dc:creator>Pernisova, M.</dc:creator>
<dc:creator>Novak, O.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:creator>Harter, K.</dc:creator>
<dc:creator>Van Der Straeten, D.</dc:creator>
<dc:creator>Hejatko, J.</dc:creator>
<dc:date>2023-01-08</dc:date>
<dc:identifier>doi:10.1101/2023.01.07.522790</dc:identifier>
<dc:title><![CDATA[Cytokinins regulate spatially-specific ethylene production to control root growth in Arabidopsis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.08.523155v1?rss=1">
<title>
<![CDATA[
Early life experience with natural odors modifies olfactory behavior through an associative process 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.08.523155v1?rss=1</link>
<description><![CDATA[
Past work has shown that chronic exposure of Drosophila to intense monomolecular odors in early life leads to homeostatic adaptation of olfactory neural responses and behavioral habituation to the familiar odor. Here, we found that, in contrast, persistent exposure to natural odors in early life increases behavioral attraction selectively to familiar odors. Odor experience increases the attractiveness of natural odors that are innately attractive and decreases the aversiveness of natural odors that are innately aversive. These changes in olfactory behavior are unlikely to arise from changes in the sensitivity of olfactory neurons at the first stages of olfactory processing: odor-evoked output from antennal lobe projection neurons was unchanged by chronic exposure to natural odors in terms of olfactory sensitivity, relational distances between odors, or response dynamics. We reveal a requirement for additional features of the environment beyond the odor in establishing odor experience-dependent behavioral plasticity. Passive odor exposure in a featureless environment lacking strong reinforcing cues was insufficient to elicit changes in olfactory preference; however, the same odor exposure resulted in behavioral plasticity when food was present in the environment. Together, these results indicate that behavioral plasticity elicited by persistent exposure to natural odors in early life is mediated by an associative process. In addition, they highlight the importance of using naturalistic odor stimuli for investigating olfactory function.
]]></description>
<dc:creator>Dylla, K. V.</dc:creator>
<dc:creator>O'Connell, T. F.</dc:creator>
<dc:creator>Hong, E. J.</dc:creator>
<dc:date>2023-01-08</dc:date>
<dc:identifier>doi:10.1101/2023.01.08.523155</dc:identifier>
<dc:title><![CDATA[Early life experience with natural odors modifies olfactory behavior through an associative process]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.11.523680v1?rss=1">
<title>
<![CDATA[
APPRAISE: Fast, accurate ranking of engineered proteins by receptor binding propensity using structural modeling 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.11.523680v1?rss=1</link>
<description><![CDATA[
Deep learning-based methods for protein structure prediction have achieved unprecedented accuracy. However, the power of these tools to guide the engineering of protein-based therapeutics remains limited due to a gap between the ability to predict the structures of candidate proteins and the ability to assess which of those proteins are most likely to bind to a target receptor. Here we bridge this gap by introducing Automated Pairwise Peptide-Receptor AnalysIs for Screening Engineered proteins (APPRAISE), a method for predicting the receptor binding propensity of engineered proteins. After generating models of engineered proteins competing for binding to a target using an established structure-prediction tool such as AlphaFold-Multimer or ESM-Fold, APPRAISE performs a rapid (under 1 CPU second per model) scoring analysis that takes into account biophysical and geometrical constraints. As a proof-of-concept, we demonstrate that APPRAISE can accurately classify receptor-dependent vs. receptor-independent adeno-associated viral vectors and diverse classes of engineered proteins such as miniproteins targeting the SARS-CoV-2 spike, nanobodies targeting a G-protein-coupled receptor, and peptides that specifically bind to transferrin receptor or PD-L1. APPRAISE is accessible through a web-based notebook interface using Google Colaboratory (https://tiny.cc/APPRAISE). With its accuracy, interpretability, and generalizability, APPRAISE promises to expand the utility of protein structure prediction and accelerate protein engineering for biomedical applications.
]]></description>
<dc:creator>Ding, X.</dc:creator>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>Sullivan, E. E.</dc:creator>
<dc:creator>Shay, T. F.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2023-01-14</dc:date>
<dc:identifier>doi:10.1101/2023.01.11.523680</dc:identifier>
<dc:title><![CDATA[APPRAISE: Fast, accurate ranking of engineered proteins by receptor binding propensity using structural modeling]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.12.523632v1?rss=1">
<title>
<![CDATA[
Primate-conserved Carbonic Anhydrase IV and murine-restricted Ly6c1 are new targets for crossing the blood-brain barrier 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.12.523632v1?rss=1</link>
<description><![CDATA[
The blood-brain barrier (BBB) presents a major challenge to delivering large molecules to study and treat the central nervous system (CNS). This is due in part to the scarcity of effective targets for BBB crossing, the identification of which is the crucial first step of drug development. Here, we leveraged a panel of adeno-associated viruses (AAVs) previously identified through directed evolution for improved BBB transport to reverse engineer protein targets for enhanced BBB crossing. We identify both murine-restricted Ly6c1 and primate-conserved carbonic anhydrase IV (Car4; CA4) as novel receptors for crossing the BBB. We demonstrate how these receptors can unlock new experimental and computational target-focused engineering strategies by creating the enhanced Ly6c1-binding vector AAV-PHP.eC and by applying AlphaFold2-enabled in silico methods to rank capsids against identified receptors and generate capsid-receptor binding models. Here, with Car4, we add a completely new receptor to the very short list currently available for crossing the BBB in humans and, with Ly6c1, we validate a pipeline for receptor-targeted engineering. The identification of Car4/CA4 and structural insights from computational modeling provide new paths toward human brain-penetrant chemicals (drugs) and biologicals (including gene delivery).
]]></description>
<dc:creator>Shay, T. F.</dc:creator>
<dc:creator>Sullivan, E. E.</dc:creator>
<dc:creator>Ding, X.</dc:creator>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>Kumar, S. R.</dc:creator>
<dc:creator>Goertsen, D.</dc:creator>
<dc:creator>Brown, D.</dc:creator>
<dc:creator>Vielmetter, J.</dc:creator>
<dc:creator>Borsos, M.</dc:creator>
<dc:creator>Lam, A. W.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2023-01-13</dc:date>
<dc:identifier>doi:10.1101/2023.01.12.523632</dc:identifier>
<dc:title><![CDATA[Primate-conserved Carbonic Anhydrase IV and murine-restricted Ly6c1 are new targets for crossing the blood-brain barrier]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.12.523844v1?rss=1">
<title>
<![CDATA[
Functional gene delivery to and across brain vasculature of systemic AAVs with endothelial-specific tropism in rodents and broad tropism in primates 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.12.523844v1?rss=1</link>
<description><![CDATA[
Delivering genes to and across the brain vasculature efficiently and specifically across species remains a critical challenge for addressing neurological diseases. We have evolved adeno-associated virus (AAV9) capsids into vectors that transduce brain endothelial cells specifically and efficiently following systemic administration in wild-type mice with diverse genetic backgrounds and rats. These AAVs also exhibit superior transduction of the CNS across non-human primates (marmosets and rhesus macaques), and ex vivo human brain slices although the endothelial tropism is not conserved across species. The capsid modifications translate from AAV9 to other serotypes such as AAV1 and AAV-DJ, enabling serotype switching for sequential AAV administration in mice. We demonstrate that the endothelial specific mouse capsids can be used to genetically engineer the blood-brain barrier by transforming the mouse brain vasculature into a functional biofactory. Vasculature-secreted Hevin (a synaptogenic protein) rescued synaptic deficits in a mouse model.
]]></description>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>Wolfe, D. A.</dc:creator>
<dc:creator>Sivadasan Bindu, D.</dc:creator>
<dc:creator>Zhang, M.</dc:creator>
<dc:creator>Taskin, N.</dc:creator>
<dc:creator>Goertsen, D.</dc:creator>
<dc:creator>Shay, T. F.</dc:creator>
<dc:creator>Sullivan, E.</dc:creator>
<dc:creator>Ravindra Kumar, S.</dc:creator>
<dc:creator>Huang, S.-F.</dc:creator>
<dc:creator>Arokiaraj, C. M.</dc:creator>
<dc:creator>Plattner, V.</dc:creator>
<dc:creator>Campos, L. J.</dc:creator>
<dc:creator>Mich, J. K.</dc:creator>
<dc:creator>Monet, D.</dc:creator>
<dc:creator>Ngo, V.</dc:creator>
<dc:creator>Ding, X.</dc:creator>
<dc:creator>Omstead, V.</dc:creator>
<dc:creator>Weed, N.</dc:creator>
<dc:creator>Bishaw, Y.</dc:creator>
<dc:creator>Gore, B. B.</dc:creator>
<dc:creator>Lein, E. S.</dc:creator>
<dc:creator>Akrami, A.</dc:creator>
<dc:creator>Miller, C.</dc:creator>
<dc:creator>Levi, B. P.</dc:creator>
<dc:creator>Keller, A.</dc:creator>
<dc:creator>Ting, J. T.</dc:creator>
<dc:creator>Fox, A. S.</dc:creator>
<dc:creator>Eroglu, C.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2023-01-13</dc:date>
<dc:identifier>doi:10.1101/2023.01.12.523844</dc:identifier>
<dc:title><![CDATA[Functional gene delivery to and across brain vasculature of systemic AAVs with endothelial-specific tropism in rodents and broad tropism in primates]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.14.524075v1?rss=1">
<title>
<![CDATA[
Dysregulated mammalian estrus cycle rescued by timed activation of VIP neurons in the circadian pacemaker and late afternoon light exposure 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.14.524075v1?rss=1</link>
<description><![CDATA[
Jet lag and shift work disrupt the menstrual cycle and decrease fertility. The circadian pacemaker, the suprachiasmatic nucleus (SCN), is known to modulate ovulation, but the mechanism is unclear. Here we explore this connection by tracking the dynamics of vasoactive intestinal peptide (VIP)-expressing neurons in the SCN in freely-behaving mice. We show that SCNVIP activity is time-of-day- and sex-dependent, and estrous-state-dependent in late afternoon, gating downstream activation of GnRH neurons. Afternoon light, as well as specific activation of SCNVIP neurons, rescues estrous cycle regularity and egg release in animals in altered light conditions, emphasizing the role of SCNVIP neurons as a time-dependent light-responsive switch. Our results reveal the dynamic mechanism by which SCNVIP neurons mediate light responses to regulate estrous states and demonstrate light-induced fertility rescue.

One Sentence SummaryModulating and recording the activity of suprachiasmatic VIP neurons in freely behaving mice reveals their regulation of fertility by mediating the response to late afternoon light.
]]></description>
<dc:creator>Kahan, A.</dc:creator>
<dc:creator>Coughlin, G. M.</dc:creator>
<dc:creator>Borsos, M.</dc:creator>
<dc:creator>Brunton, B. W.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2023-01-17</dc:date>
<dc:identifier>doi:10.1101/2023.01.14.524075</dc:identifier>
<dc:title><![CDATA[Dysregulated mammalian estrus cycle rescued by timed activation of VIP neurons in the circadian pacemaker and late afternoon light exposure]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.16.524176v1?rss=1">
<title>
<![CDATA[
In situ architecture of Opa1-dependent mitochondrial cristae remodeling 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.16.524176v1?rss=1</link>
<description><![CDATA[
Cristae membrane state plays a central role in regulating mitochondrial function and cellular metabolism. The protein Optic atrophy 1 (Opa1) is an important crista remodeler that exists as two forms in the mitochondrion, a membrane-anchored long form (l-Opa1) and a processed short form (s-Opa1). The mechanisms for how Opa1 influences cristae shape have remained unclear due to lack of native three-dimensional views of cristae. We perform in situ cryo-electron tomography of cryo-focused ion beam milled mouse embryonic fibroblasts with defined Opa1 states to understand how each form of Opa1 influences cristae architecture. In our tomograms, we observe a variety of cristae shapes with distinct trends dependent on s-Opa1:l-Opa1 balance. Increased l-Opa1 levels promote cristae stacking and elongated mitochondria while increased s-Opa1 levels correlated with irregular cristae packing and round mitochondria shape. Functional assays indicate a role for l-Opa1 in wild-type apoptotic and calcium handling responses, and compromised respiratory function under Opa1 imbalance. In summary, we provide three-dimensional visualization of cristae architecture to reveal relationships between mitochondrial ultrastructure and cellular function dependent on Opa1-mediated membrane remodeling.

HighlightsO_LIIn situ ultrastructural characterization of mitochondrial cristae with different forms of Opa1.
C_LIO_LIMitochondria with predominantly l-Opa1 show crista stacking, longer cristae, reduced globular cristae and an absence of tubular cristae.
C_LIO_LIMitochondria with mostly s-Opa1 showed irregular cristae packing with wider cristae junctions and narrower cristae.
C_LIO_LIl-Opa1 expressing cells with WT-like cristae junction properties, show wild-type apoptotic response and calcium handling.
C_LIO_LIImbalance in Opa1 processing show compromised respiratory function and an increase in amorphous cristae.
C_LI
]]></description>
<dc:creator>Fry, M. Y.</dc:creator>
<dc:creator>Navarro, P. P.</dc:creator>
<dc:creator>Qin, X.</dc:creator>
<dc:creator>Inde, Z.</dc:creator>
<dc:creator>Ananda, V. Y.</dc:creator>
<dc:creator>Lugo, C. M.</dc:creator>
<dc:creator>Hakim, P.</dc:creator>
<dc:creator>Luce, B. E.</dc:creator>
<dc:creator>Ge, Y.</dc:creator>
<dc:creator>McDonald, J. L.</dc:creator>
<dc:creator>Ali, I.</dc:creator>
<dc:creator>Ha, L. L.</dc:creator>
<dc:creator>Kleinstiver, B. P.</dc:creator>
<dc:creator>Chan, D. C.</dc:creator>
<dc:creator>Sarosiek, K.</dc:creator>
<dc:creator>Chao, L. H.</dc:creator>
<dc:date>2023-01-18</dc:date>
<dc:identifier>doi:10.1101/2023.01.16.524176</dc:identifier>
<dc:title><![CDATA[In situ architecture of Opa1-dependent mitochondrial cristae remodeling]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.16.524298v1?rss=1">
<title>
<![CDATA[
Interactive computational and experimental approaches improve the sensitivity of periplasmic binding protein-based nicotine biosensors for measurements in biofluids 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.16.524298v1?rss=1</link>
<description><![CDATA[
We developed fluorescent protein sensors for nicotine with improved sensitivity. For iNicSnFR12 at pH 7.4, the proportionality constant for {Delta}F/F0 vs [nicotine] ({delta}-slope, 2.7 M-1) is 6.1-fold higher than the previously reported iNicSnFR3a. The activated state of iNicSnFR12 has a fluorescence quantum yield of at least 0.6. We measured similar dose-response relations for the nicotine-induced absorbance increase and fluorescence increase, suggesting that the absorbance increase leads to the fluorescence increase via the previously described nicotine-induced conformational change, the "candle snuffer" mechanism. Molecular dynamics (MD) simulations identified a binding pose for nicotine, previously indeterminate from experimental data. MD simulations also showed that Helix 4 of the periplasmic binding protein (PBP) domain appears tilted in iNicSnFR12 relative to iNicSnFR3a, likely altering allosteric network(s) that link the ligand binding site to the fluorophore. In thermal melt experiments, nicotine stabilized the PBP of the tested iNicSnFR variants. iNicSnFR12 resolved nicotine in diluted mouse and human serum at 100 nM, the peak [nicotine] that occurs during smoking or vaping, and possibly at the decreasing levels during intervals between sessions. NicSnFR12 was also partially activated by unidentified endogenous ligand(s) in biofluids. Improved iNicSnFR12 variants could become the molecular sensors in continuous nicotine monitors for animal and human biofluids.
]]></description>
<dc:creator>Haloi, N.</dc:creator>
<dc:creator>Huang, S.</dc:creator>
<dc:creator>Nichols, A.</dc:creator>
<dc:creator>Fine, E. J.</dc:creator>
<dc:creator>Marotta, C. B.</dc:creator>
<dc:creator>Dougherty, D. A.</dc:creator>
<dc:creator>Lindahl, E.</dc:creator>
<dc:creator>Howard, R. J.</dc:creator>
<dc:creator>Mayo, S. L.</dc:creator>
<dc:creator>Lester, H. A.</dc:creator>
<dc:date>2023-01-19</dc:date>
<dc:identifier>doi:10.1101/2023.01.16.524298</dc:identifier>
<dc:title><![CDATA[Interactive computational and experimental approaches improve the sensitivity of periplasmic binding protein-based nicotine biosensors for measurements in biofluids]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.17.524309v1?rss=1">
<title>
<![CDATA[
The telegraph process is not a subordinator 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.17.524309v1?rss=1</link>
<description><![CDATA[
Investigations of transcriptional models by Amrhein et al. outline a strategy for connecting steady-state distributions to process dynamics. We clarify its limitations: the strategy holds for a very narrow class of processes, which excludes an example given by the authors.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2023-01-18</dc:date>
<dc:identifier>doi:10.1101/2023.01.17.524309</dc:identifier>
<dc:title><![CDATA[The telegraph process is not a subordinator]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.22.525086v1?rss=1">
<title>
<![CDATA[
A dual sgRNA library design to probe genetic modifiers using genome-wide CRISPRi screens 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.22.525086v1?rss=1</link>
<description><![CDATA[
Mapping genetic interactions is essential for determining gene function and defining novel biological pathways. We report a simple to use CRISPR interference (CRISPRi) based platform, compatible with Fluorescence Activated Cell Sorting (FACS)-based reporter screens, to query epistatic relationships at scale. This is enabled by a flexible dual-sgRNA library design that allows for the simultaneous delivery and selection of a fixed sgRNA and a second randomized guide, comprised of a genome-wide library, with a single transduction. We use this approach to identify epistatic relationships for a defined biological pathway, showing both increased sensitivity and specificity than traditional growth screening approaches.
]]></description>
<dc:creator>Guna, A.</dc:creator>
<dc:creator>Page, K. R.</dc:creator>
<dc:creator>Replogle, J. R.</dc:creator>
<dc:creator>Esantsi, T. K.</dc:creator>
<dc:creator>Wang, M. L.</dc:creator>
<dc:creator>Weissman, J. S.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:date>2023-01-22</dc:date>
<dc:identifier>doi:10.1101/2023.01.22.525086</dc:identifier>
<dc:title><![CDATA[A dual sgRNA library design to probe genetic modifiers using genome-wide CRISPRi screens]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.23.525254v1?rss=1">
<title>
<![CDATA[
Network structure influences the strength of learned neural representations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.23.525254v1?rss=1</link>
<description><![CDATA[
Human experience is built upon sequences of discrete events. From those sequences, humans build impressively accurate models of their world. This process has been referred to as graph learning, a form of structure learning in which the mental model encodes the graph of event-to-event transition probabilities [1], [2], typically in medial temporal cortex [3]-[6]. Recent evidence suggests that some network structures are easier to learn than others [7]-[9], but the neural properties of this effect remain unknown. Here we use fMRI to show that the network structure of a temporal sequence of stimuli influences the fidelity with which those stimuli are represented in the brain. Healthy adult human participants learned a set of stimulus-motor associations following one of two graph structures. The design of our experiment allowed us to separate regional sensitivity to the structural, stimulus, and motor response components of the task. As expected, whereas the motor response could be decoded from neural representations in postcentral gyrus, the shape of the stimulus could be decoded from lateral occipital cortex. The structure of the graph impacted the nature of neural representations: when the graph was modular as opposed to lattice-like, BOLD representations in visual areas better predicted trial identity in a held-out run and displayed higher intrinsic dimensionality. Our results demonstrate that even over relatively short timescales, graph structure determines the fidelity of event representations as well as the dimensionality of the space in which those representations are encoded. More broadly, our study shows that network context influences the strength of learned neural representations, motivating future work in the design, optimization, and adaptation of network contexts for distinct types of learning over different timescales.
]]></description>
<dc:creator>Kahn, A. E.</dc:creator>
<dc:creator>Szymula, K.</dc:creator>
<dc:creator>Bassett, D. S.</dc:creator>
<dc:creator>Nyema, N.</dc:creator>
<dc:creator>Haggerty, E. B.</dc:creator>
<dc:creator>Aguirre, G. K.</dc:creator>
<dc:date>2023-01-24</dc:date>
<dc:identifier>doi:10.1101/2023.01.23.525254</dc:identifier>
<dc:title><![CDATA[Network structure influences the strength of learned neural representations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.26.525637v1?rss=1">
<title>
<![CDATA[
Neural substrates of parallel devaluation-sensitive and devaluation-insensitive Pavlovian learning in humans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.26.525637v1?rss=1</link>
<description><![CDATA[
Pavlovian learning depends on multiple and parallel associations leading to distinct classes of conditioned responses that vary in their flexibility following changes in the value of an associated outcome. Here, we aimed to differentiate brain areas involved in learning and encoding associations that are sensitive to changes in the value of an outcome from those that are not sensitive to such changes. To address this question, we combined a Pavlovian learning task with outcome devaluation, eye-tracking and functional magnetic resonance imaging. We used computational modeling to identify brain regions involved in learning stimulus-reward associations and stimulus-stimulus associations, by testing for brain areas correlating with reward-prediction errors and state-prediction errors, respectively. We found that, contrary to theoretical predictions about reward prediction errors being exclusively model-free, voxels correlating with reward prediction errors in the ventral striatum and subgenual anterior cingulate cortex were sensitive to devaluation. On the other hand, brain areas correlating with state prediction errors were found to be devaluation insensitive. In a supplementary analysis, we distinguished brain regions encoding predictions about outcome taste identity from those involved in encoding predictions about its expected spatial location. A subset of regions involved in taste identity predictions were devaluation sensitive while those involved in encoding predictions about spatial location were devaluation insensitive. These findings provide insights into the role of multiple associative mechanisms in the brain in mediating Pavlovian conditioned behavior - illustrating how distinct neural pathways can in parallel produce both devaluation sensitive and devaluation insensitive behaviors.
]]></description>
<dc:creator>Pool, E. R.</dc:creator>
<dc:creator>Pauli, W. M.</dc:creator>
<dc:creator>Cross, L.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:date>2023-01-27</dc:date>
<dc:identifier>doi:10.1101/2023.01.26.525637</dc:identifier>
<dc:title><![CDATA[Neural substrates of parallel devaluation-sensitive and devaluation-insensitive Pavlovian learning in humans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.29.526047v1?rss=1">
<title>
<![CDATA[
Staphylococcal secreted cytotoxins are competition sensing signals for Pseudomonas aeruginosa 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.29.526047v1?rss=1</link>
<description><![CDATA[
Coinfection with two notorious opportunistic pathogens, the Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus, dominates chronic pulmonary infections. While coinfection is associated with poor patient outcomes, the interspecies interactions responsible for such decline remain unknown. Here, we dissected molecular mechanisms of interspecies sensing between P. aeruginosa and S. aureus. We discovered that P. aeruginosa senses S. aureus secreted peptides and, counterintuitively, moves towards these toxins. P. aeruginosa tolerates such a strategy through "competition sensing", whereby it preempts imminent danger/competition by arming cells with type six secretion (T6S) and iron acquisition systems. Intriguingly, while T6S is predominantly described as weaponry targeting Gram-negative and eukaryotic cells, we find that T6S is essential for full P. aeruginosa competition with S. aureus, a previously undescribed role for T6S. Importantly, competition sensing was activated during coinfection of bronchial epithelia, including T6S islands targeting human cells. This study reveals critical insight into both interspecies competition and how antagonism may cause collateral damage to the host environment.
]]></description>
<dc:creator>Wang, G. Z.</dc:creator>
<dc:creator>Warren, E. A.</dc:creator>
<dc:creator>Haas, A. L.</dc:creator>
<dc:creator>Pena, A. S.</dc:creator>
<dc:creator>Kiedrowski, M. R.</dc:creator>
<dc:creator>Lomenick, B.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Bomberger, J. M.</dc:creator>
<dc:creator>Tirrell, D. A.</dc:creator>
<dc:creator>Limoli, D. H.</dc:creator>
<dc:date>2023-01-29</dc:date>
<dc:identifier>doi:10.1101/2023.01.29.526047</dc:identifier>
<dc:title><![CDATA[Staphylococcal secreted cytotoxins are competition sensing signals for Pseudomonas aeruginosa]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.01.526664v1?rss=1">
<title>
<![CDATA[
Large-scale brain-wide neural recording in nonhuman primates 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.01.526664v1?rss=1</link>
<description><![CDATA[
High-density, integrated silicon electrodes have begun to transform systems neuroscience, by enabling large-scale neural population recordings with single cell resolution. Existing technologies, however, have provided limited functionality in nonhuman primate species such as macaques, which offer close models of human cognition and behavior. Here, we report the design, fabrication, and performance of Neuropixels 1.0-NHP, a high channel count linear electrode array designed to enable large-scale simultaneous recording in superficial and deep structures within the macaque or other large animal brain. These devices were fabricated in two versions: 4416 electrodes along a 45 mm shank, and 2496 along a 25 mm shank. For both versions, users can programmatically select 384 channels, enabling simultaneous multi-area recording with a single probe. We demonstrate recording from over 3000 single neurons within a session, and simultaneous recordings from over 1000 neurons using multiple probes. This technology represents a significant increase in recording access and scalability relative to existing technologies, and enables new classes of experiments involving fine-grained electrophysiological characterization of brain areas, functional connectivity between cells, and simultaneous brain-wide recording at scale.
]]></description>
<dc:creator>Trautmann, E. M.</dc:creator>
<dc:creator>Hesse, J. K.</dc:creator>
<dc:creator>Stine, G.</dc:creator>
<dc:creator>Xia, R.</dc:creator>
<dc:creator>Shude Zhu, S.</dc:creator>
<dc:creator>O'Shea, D. J.</dc:creator>
<dc:creator>Karsh, B.</dc:creator>
<dc:creator>Colonell, J.</dc:creator>
<dc:creator>Lanfranchi, F.</dc:creator>
<dc:creator>Vyas, S.</dc:creator>
<dc:creator>Zimnik, A.</dc:creator>
<dc:creator>Steinemann, N. A.</dc:creator>
<dc:creator>Wagenaar, D. A.</dc:creator>
<dc:creator>Andrei, A.</dc:creator>
<dc:creator>Mora Lopez, C.</dc:creator>
<dc:creator>OCallaghan, J. M.</dc:creator>
<dc:creator>Putzeys, J.</dc:creator>
<dc:creator>Raducanu, B. C.</dc:creator>
<dc:creator>Welkenhuysen, M.</dc:creator>
<dc:creator>Churchland, M.</dc:creator>
<dc:creator>Moore, T.</dc:creator>
<dc:creator>Shadlen, M. N.</dc:creator>
<dc:creator>Shenoy, K. V.</dc:creator>
<dc:creator>Tsao, D.</dc:creator>
<dc:creator>Dutta, B.</dc:creator>
<dc:creator>Harris, T.</dc:creator>
<dc:date>2023-02-03</dc:date>
<dc:identifier>doi:10.1101/2023.02.01.526664</dc:identifier>
<dc:title><![CDATA[Large-scale brain-wide neural recording in nonhuman primates]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.02.526862v1?rss=1">
<title>
<![CDATA[
Maternal hormones engage a dormant monomorphic aggression circuit, leading to the introduction of an innate behavior in adulthood in females 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.02.526862v1?rss=1</link>
<description><![CDATA[
Aggression, a sexually dimorphic behaviour, is prevalent in males and typically absent in virgin females. Following parturition, however, the transient expression of aggression in adult female mice protects pups from predators and infanticide by male conspecifics. While maternal hormones are known to elicit nursing, their potential role in maternal aggression remains elusive. Here, we show in mice that a molecularly defined subset of ventral premammillary (PMvDAT) neurons, instrumental for intermale aggression, switch from quiescence to a hyperexcitable state during lactation. We identify that the maternal hormones prolactin and oxytocin excite these cells through actions that include T-type Ca2+ channels. Optogenetic manipulation or genetic ablation of PMvDAT neurons profoundly affects maternal aggression, while activation of these neurons impairs the expression of non-aggression-related maternal behaviours. This work identifies a monomorphic neural substrate that can incorporate hormonal cues to enable the transient expression of a dormant behavioural program in lactating females.
]]></description>
<dc:creator>Stagkourakis, S.</dc:creator>
<dc:creator>Williams, P.</dc:creator>
<dc:creator>Spigolon, G.</dc:creator>
<dc:creator>Khanal, S.</dc:creator>
<dc:creator>Ziegler, K.</dc:creator>
<dc:creator>Heikkinen, L.</dc:creator>
<dc:creator>Fisone, G.</dc:creator>
<dc:creator>Broberger, C.</dc:creator>
<dc:date>2023-02-03</dc:date>
<dc:identifier>doi:10.1101/2023.02.02.526862</dc:identifier>
<dc:title><![CDATA[Maternal hormones engage a dormant monomorphic aggression circuit, leading to the introduction of an innate behavior in adulthood in females]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.05.527206v1?rss=1">
<title>
<![CDATA[
Mob4 is essential for spermatogenesis in Drosophila melanogaster 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.05.527206v1?rss=1</link>
<description><![CDATA[
Gamete formation is essential for sexual reproduction in metazoans. In males, spermatogenesis gives rise to interconnected spermatids that have to differentiate and individualize into mature sperm. In Drosophila melanogaster, individualization of spermatids requires the formation of individualization complexes that synchronously move along the sperm bundles. Here, we show that Mob4, a member of the Mps-one binder family, is essential for male fertility but has no detectable role on female fertility. We describe the function of Mob4 during spermatid individualization, showing that Mob4 is required for proper axonemal structure and that the loss of Mob4 leads to male sterility associated with defective spermatid individualization and absence of mature sperm in the seminal vesicles. Transmission electron micrographs of Mob4RNAi developing spermatids revealed defects in axoneme structure and abnormal mitochondria biogenesis. Importantly, we find that male fertility is impaired upon depletion of other STRIPAK components, suggesting that Mob4 acts through STRIPAK to support spermiogenesis. As we show that expression of the human Mob4 gene effectively rescues all phenotypes of Mob4 downregulation, the gene is not only evolutionary but also functionally conserved. We propose that Mob4 plays a role in regulating the microtubule- and actin-cytoskeleton during spermatogenesis. This study advances our understanding of male infertility by uncovering Mob4 as a novel gene required for sperm individualization.
]]></description>
<dc:creator>Santos, I. B.</dc:creator>
<dc:creator>Wainman, A.</dc:creator>
<dc:creator>Maraver, J. G.</dc:creator>
<dc:creator>Pires, V.</dc:creator>
<dc:creator>Kovacs, L.</dc:creator>
<dc:creator>Riparbelli, M. G.</dc:creator>
<dc:creator>Callaini, G.</dc:creator>
<dc:creator>Glover, D. M.</dc:creator>
<dc:creator>Tavares, A. A.</dc:creator>
<dc:date>2023-02-05</dc:date>
<dc:identifier>doi:10.1101/2023.02.05.527206</dc:identifier>
<dc:title><![CDATA[Mob4 is essential for spermatogenesis in Drosophila melanogaster]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.07.527479v1?rss=1">
<title>
<![CDATA[
POLCAM: Instant molecular orientation microscopy for the life sciences 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.07.527479v1?rss=1</link>
<description><![CDATA[
Current methods for single-molecule orientation localization microscopy (SMOLM) require optical setups and algorithms that can be prohibitively slow and complex, limiting the widespread adoption for biological applications. We present POLCAM, a simplified SMOLM method based on polarized detection using a polarization camera, that can be easily implemented on any wide-field fluorescence microscope. To make polarization cameras compatible with single-molecule detection, we developed theory to minimize field of view errors, used simulations to optimize experimental design, and developed a fast algorithm based on Stokes parameter estimation which can operate over 1000 fold faster than the state of the art, enabling near instant determination of molecular anisotropy. To aid in the adoption of POLCAM, we developed open-source image analysis software, and a website detailing hardware installation and software use. To illustrate the potential of POLCAM in the life sciences, we applied our method to study alpha-synuclein fibrils, the actin cytoskeleton of mammalian cells, fibroblast-like cells and the plasma membrane of live human T cells.
]]></description>
<dc:creator>Bruggeman, E.</dc:creator>
<dc:creator>Zhang, O.</dc:creator>
<dc:creator>Needham, L.-M.</dc:creator>
<dc:creator>Koerbel, M.</dc:creator>
<dc:creator>Daly, S.</dc:creator>
<dc:creator>Cheetham, M.</dc:creator>
<dc:creator>Peters, R.</dc:creator>
<dc:creator>Wu, T.</dc:creator>
<dc:creator>Klymchenko, A. S.</dc:creator>
<dc:creator>Davis, S. J.</dc:creator>
<dc:creator>Paluch, E. K.</dc:creator>
<dc:creator>Klenerman, D.</dc:creator>
<dc:creator>Lew, M. D.</dc:creator>
<dc:creator>O'Holleran, K.</dc:creator>
<dc:creator>Lee, S. F.</dc:creator>
<dc:date>2023-02-08</dc:date>
<dc:identifier>doi:10.1101/2023.02.07.527479</dc:identifier>
<dc:title><![CDATA[POLCAM: Instant molecular orientation microscopy for the life sciences]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.08.527750v1?rss=1">
<title>
<![CDATA[
LINKIN-associated proteins necessary for tissue integrity during collective cell migration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.08.527750v1?rss=1</link>
<description><![CDATA[
Cell adhesion plays essential roles in almost every aspect of metazoan biology. LINKIN (Human: ITFG1, Caenorhabditis elegans: lnkn-1) is a conserved transmembrane protein that has been identified to be necessary for tissue integrity during migration. In C. elegans, loss of lnkn-1 results in the detachment of the lead migratory cell from the rest of the developing male gonad. Previously, three interactors of ITFG1/lnkn-1 - RUVBL1/ruvb-1, RUVBL2/ruvb-2, and alpha-tubulin - were identified by immunoprecipitation-mass spectrometry (IP-MS) analysis using human HEK293T cells and then validated in the nematode male gonad. The ITFG1-RUVBL1 interaction has since been independently validated in a breast cancer cell line model that also implicates the involvement of the pair in metastasis. Here, we showed that epitope-tagged ITFG1 localized to the cell surface of MDA-MB-231 breast cancer cells. Using IP-MS analysis, we identified a new list of potential interactors of ITFG1. Loss-of-function analysis of their C. elegans orthologs found that three of the interactors - ATP9A/tat-5, NME1/ndk-1, and ANAPC2/apc-2 - displayed migratory detachment phenotypes similar to that of lnkn-1. Taken together with the other genes whose reduction-of-function phenotype is similar to that of lnkn-1 (notably cohesion and condensin), suggests the involvement of membrane remodeling and chromosome biology in LINKIN-dependent cell adhesion and supports the hypothesis for a structural role of chromosomes in post-mitotic cells.
]]></description>
<dc:creator>Tan, C.-H.</dc:creator>
<dc:creator>Cheng, K.-W.</dc:creator>
<dc:creator>Park, H.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2023-02-09</dc:date>
<dc:identifier>doi:10.1101/2023.02.08.527750</dc:identifier>
<dc:title><![CDATA[LINKIN-associated proteins necessary for tissue integrity during collective cell migration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.15.528627v1?rss=1">
<title>
<![CDATA[
Restructuring of olfactory representations in the fly brain around odor relationships in natural sources 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.15.528627v1?rss=1</link>
<description><![CDATA[
A core challenge of olfactory neuroscience is to understand how neural representations of odor are generated and progressively transformed across different layers of the olfactory circuit into formats that support perception and behavior. The encoding of odor by odorant receptors in the input layer of the olfactory system reflects, at least in part, the chemical relationships between odor compounds. Neural representations of odor in higher order associative olfactory areas, generated by random feedforward networks, are expected to largely preserve these input odor relationships1-3. We evaluated these ideas by examining how odors are represented at different stages of processing in the olfactory circuit of the vinegar fly D. melanogaster. We found that representations of odor in the mushroom body (MB), a third-order associative olfactory area in the fly brain, are indeed structured and invariant across flies. However, the structure of MB representational space diverged significantly from what is expected in a randomly connected network. In addition, odor relationships encoded in the MB were better correlated with a metric of the similarity of their distribution across natural sources compared to their similarity with respect to chemical features, and the converse was true for odor relationships encoded in primary olfactory receptor neurons (ORNs). Comparison of odor coding at primary, secondary, and tertiary layers of the circuit revealed that odors were significantly regrouped with respect to their representational similarity across successive stages of olfactory processing, with the largest changes occurring in the MB. The non-linear reorganization of odor relationships in the MB indicates that unappreciated structure exists in the fly olfactory circuit, and this structure may facilitate the generalization of odors with respect to their co-occurence in natural sources.
]]></description>
<dc:creator>Yang, J.-Y.</dc:creator>
<dc:creator>O'Connell, T. F.</dc:creator>
<dc:creator>Hsu, W.-M. M.</dc:creator>
<dc:creator>Bauer, M. S.</dc:creator>
<dc:creator>Dylla, K. V.</dc:creator>
<dc:creator>Sharpee, T. O.</dc:creator>
<dc:creator>Hong, E. J.</dc:creator>
<dc:date>2023-02-15</dc:date>
<dc:identifier>doi:10.1101/2023.02.15.528627</dc:identifier>
<dc:title><![CDATA[Restructuring of olfactory representations in the fly brain around odor relationships in natural sources]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.15.528637v1?rss=1">
<title>
<![CDATA[
Pervasive, conserved secondary structure in highly charged protein regions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.15.528637v1?rss=1</link>
<description><![CDATA[
Understanding how protein sequences confer function remains a defining challenge in molecular biology. Two approaches have yielded enormous insight yet are often pursued separately: structure-based, where sequence-encoded structures mediate function, and disorder-based, where sequences dictate physicochemical and dynamical properties which determine function in the absence of stable structure. Here we study highly charged protein regions (>40% charged residues), which are routinely presumed to be disordered. Using recent advances in structure prediction and experimental structures, we show that roughly 40% of these regions form well-structured helices. Features often used to predict disorder--high charge density, low hydrophobicity, low sequence complexity, and evolutionarily varying length--are also compatible with solvated, variable-length helices. We show that a simple composition classifier predicts the existence of structure far better than well-established heuristics based on charge and hydropathy. We show that helical structure is more prevalent than previously appreciated in highly charged regions of diverse proteomes and characterize the conservation of highly charged regions. Our results underscore the importance of integrating, rather than choosing between, structure- and disorder-based approaches.
]]></description>
<dc:creator>Triandafillou, C. G.</dc:creator>
<dc:creator>Pan, R. W.</dc:creator>
<dc:creator>Dinner, A. R.</dc:creator>
<dc:creator>Drummond, D. A.</dc:creator>
<dc:date>2023-02-15</dc:date>
<dc:identifier>doi:10.1101/2023.02.15.528637</dc:identifier>
<dc:title><![CDATA[Pervasive, conserved secondary structure in highly charged protein regions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.22.529174v1?rss=1">
<title>
<![CDATA[
Dynamical states of self-organized waves in a giant single-celled organism feeding on light 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.22.529174v1?rss=1</link>
<description><![CDATA[
A hallmark of self-organisation in living systems is their capacity to stabilise their own dynamics, often appearing to anticipate and act upon potential outcomes. Caulerpa brachypus is a marine green alga consisting of differentiated organs resembling leaves, stems and roots. While an individual can exceed a metre in size, it is a single multinucleated giant cell. Thus Caulerpa presents the mystery of morphogenesis on macroscopic scales in the absence of cellularization. The experiments reported here reveal self-organised waves of greenness -- chloroplasts -- that propagate throughout the alga in anticipation of the day-night light cycle. Using dynamical systems analysis we show that these waves are coupled to a self-sustained oscillator, and demonstrate their entrainment to light. Under constant conditions light intensity affects the natural period and drives transition to temporal disorder. Moreover, we find distinct morphologies depending on light temporal patterns, suggesting waves of chlorophyll could link biological oscillators to metabolism and morphogenesis in this giant single-celled organism.
]]></description>
<dc:creator>Afik, E.</dc:creator>
<dc:creator>Liu, T. J.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:date>2023-02-22</dc:date>
<dc:identifier>doi:10.1101/2023.02.22.529174</dc:identifier>
<dc:title><![CDATA[Dynamical states of self-organized waves in a giant single-celled organism feeding on light]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.24.529520v1?rss=1">
<title>
<![CDATA[
Multiviral Quartet Nanocages Elicit Broad Anti-Coronavirus Responses for Proactive Vaccinology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.24.529520v1?rss=1</link>
<description><![CDATA[
Defending against future pandemics may require vaccine platforms that protect across a range of related pathogens. The presentation of multiple receptor-binding domains (RBDs) from evolutionarily-related viruses on a nanoparticle scaffold elicits a strong antibody response to conserved regions. Here we produce quartets of tandemly-linked RBDs from SARS-like betacoronaviruses coupled to the mi3 nanocage through a SpyTag/SpyCatcher spontaneous reaction. These Quartet Nanocages induce a high level of neutralizing antibodies against several different coronaviruses, including against viruses not represented on the vaccine. In animals primed with SARS-CoV-2 Spike, boost immunizations with Quartet Nanocages increased the strength and breadth of an otherwise narrow immune response. Quartet Nanocages are a strategy with potential to confer heterotypic protection against emergent zoonotic coronavirus pathogens and facilitate proactive pandemic protection.

One Sentence SummaryA vaccine candidate with polyprotein antigens displayed on nanocages induces neutralizing antibodies to multiple SARS-like coronaviruses.
]]></description>
<dc:creator>Hills, R. A.</dc:creator>
<dc:creator>Tan, T. K.</dc:creator>
<dc:creator>Cohen, A. A.</dc:creator>
<dc:creator>Keefe, J. R.</dc:creator>
<dc:creator>Keeble, A. H.</dc:creator>
<dc:creator>Gnanapragasam, P. N.</dc:creator>
<dc:creator>Storm, K. N.</dc:creator>
<dc:creator>Hill, M. L.</dc:creator>
<dc:creator>Liu, S.</dc:creator>
<dc:creator>Gilbert-Jaramillo, J.</dc:creator>
<dc:creator>Afzal, M.</dc:creator>
<dc:creator>Napier, A.</dc:creator>
<dc:creator>James, W. S.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Townsend, A. R.</dc:creator>
<dc:creator>Howarth, M.</dc:creator>
<dc:date>2023-02-24</dc:date>
<dc:identifier>doi:10.1101/2023.02.24.529520</dc:identifier>
<dc:title><![CDATA[Multiviral Quartet Nanocages Elicit Broad Anti-Coronavirus Responses for Proactive Vaccinology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.27.530195v1?rss=1">
<title>
<![CDATA[
Label-free differential imaging of cellular components in mouse brain tissue by wide-band photoacoustic microscopy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.27.530195v1?rss=1</link>
<description><![CDATA[
Mapping diverse cellular components with high spatial resolution is important to interrogate biological systems and study disease pathogenesis. Conventional optical imaging techniques for mapping biomolecular profiles with differential staining and labeling methods are cumbersome. Different types of cellular components exhibit distinctive characteristic absorption spectra across a wide wavelength range. By virtue of this property, a lab-made wide-band optical-resolution photoacoustic microscopy (wbOR-PAM) system, which covers wavelengths from the ultraviolet and visible to the shortwave infrared regions, was designed and developed to capture multiple cellular components in 300-m-thick brain slices at nine different wavelengths without repetitive staining and complicated processing. This wbOR-PAM system provides abundant spectral information. A reflective objective lens with an infinite conjugate design was applied to focus laser beams with different wavelengths, avoiding chromatic aberration. The molecular components of complex brain slices were probed without labeling. The findings of the present study demonstrated a distinctive absorption of phospholipids, a major component of the cell membrane, brain, and nervous system, at 1690 nm and revealed their precise distribution with microscopic resolution in a mouse brain, for the first time. This novel imaging modality provides a new opportunity to investigate important biomolecular components without either labeling or lengthy specimen processing, thus, laying the groundwork for revealing cellular mechanisms involved in disease pathogenesis.
]]></description>
<dc:creator>Liu, Y.</dc:creator>
<dc:creator>Wong, T. T.</dc:creator>
<dc:creator>Shi, J.</dc:creator>
<dc:creator>He, Y.</dc:creator>
<dc:creator>Nie, L.</dc:creator>
<dc:creator>V. Wang, L.</dc:creator>
<dc:date>2023-02-28</dc:date>
<dc:identifier>doi:10.1101/2023.02.27.530195</dc:identifier>
<dc:title><![CDATA[Label-free differential imaging of cellular components in mouse brain tissue by wide-band photoacoustic microscopy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.09.531949v1?rss=1">
<title>
<![CDATA[
A rapid, multiplex digital PCR assay for EGFR, KRAS, BRAF, ERBB2 variants and ALK, RET, ROS1, NTRK1 gene fusions in non-small cell lung cancer 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.09.531949v1?rss=1</link>
<description><![CDATA[
Digital PCR (dPCR) is emerging as an ideal platform for the detection and tracking of genomic variants in cancer due to its high sensitivity and simple workflow. The growing number of clinically-actionable cancer biomarkers creates a need for fast, accessible methods that allow for dense information content and high accuracy. Here, we describe a proof-of-concept amplitude modulation based multiplex dPCR assay capable of detecting 12 single nucleotide and indel variants in EGFR, KRAS, BRAF, and ERBB2, 14 gene fusions in ALK, RET, ROS1, NTRK1, and MET exon 14 skipping present in non-small cell lung cancer (NSCLC). We also demonstrate the use of multi-spectral target signal encoding to improve the specificity of variant detection by reducing background noise up to 11-fold. The assay reported an overall 100% PPA and 98.5% NPA compared to a sequencing-based assay in a cohort of 62 human FFPE samples. In addition, the dPCR assay rescued actionable information in 10 samples that failed to sequence, highlighting the utility of a multiplexed digital assay as a potential reflex solution for challenging NSCLC samples.
]]></description>
<dc:creator>Leatham, B.</dc:creator>
<dc:creator>McNall, K.</dc:creator>
<dc:creator>Subramanian, H. K.</dc:creator>
<dc:creator>Jacky, L.</dc:creator>
<dc:creator>Alvarado, J. G.</dc:creator>
<dc:creator>Yurk, D.</dc:creator>
<dc:creator>Wang, M.</dc:creator>
<dc:creator>Green, D. C.</dc:creator>
<dc:creator>Tsongalis, G. J.</dc:creator>
<dc:creator>Rajagopal, A.</dc:creator>
<dc:creator>Schwartz, J.</dc:creator>
<dc:date>2023-03-12</dc:date>
<dc:identifier>doi:10.1101/2023.03.09.531949</dc:identifier>
<dc:title><![CDATA[A rapid, multiplex digital PCR assay for EGFR, KRAS, BRAF, ERBB2 variants and ALK, RET, ROS1, NTRK1 gene fusions in non-small cell lung cancer]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.09.531980v1?rss=1">
<title>
<![CDATA[
A nanobody-based strategy for rapid and scalable purification of native human protein complexes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.09.531980v1?rss=1</link>
<description><![CDATA[
Native isolation of proteins in high yield and purity is a major bottleneck for analysis of their three- dimensional structure, function, and interactome. Here, we present a streamlined workflow for the rapid production of proteins or protein complexes using lentiviral transduction of human suspension cells, combined with highly-specific nanobody-mediated purification and proteolytic elution. (1) First, generation of a plasmid coding for a protein of interest fused to an N- or C- terminal GFP or ALFA peptide tag is rapidly achieved using the lentiviral plasmid toolkit we have designed. (2) Human suspension cell lines stably expressing the tagged fusion protein can be generated in <5 days using lentiviral transduction. (3) Leveraging the picomolar affinity of the GFP and ALFA nanobodies for their respective tags, proteins expressed even at low levels can be specifically captured from the resulting cell lysate in a variety of conditions, including detergents and mild denaturants. (4) Finally, rapid and specific elution of tagged or untagged proteins under native conditions is achieved within minutes at 4{degrees}C using an engineered SUMO protease. We demonstrate the wide applicability of the method by purifying multiple challenging soluble and membrane protein complexes to high purity from human cells. Our strategy is also directly compatible with many widely used GFP expression plasmids, cell lines and transgenic model organisms; is faster than alternative approaches, requiring [~]8 days from cloning to purification; and results in substantially improved yields and purity.
]]></description>
<dc:creator>Stevens, T. A.</dc:creator>
<dc:creator>Tomaleri, G. P.</dc:creator>
<dc:creator>Hazu, M.</dc:creator>
<dc:creator>Wei, S.</dc:creator>
<dc:creator>Nguyen, V. N.</dc:creator>
<dc:creator>DeKalb, C.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:creator>Pleiner, T.</dc:creator>
<dc:date>2023-03-10</dc:date>
<dc:identifier>doi:10.1101/2023.03.09.531980</dc:identifier>
<dc:title><![CDATA[A nanobody-based strategy for rapid and scalable purification of native human protein complexes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.11.532232v1?rss=1">
<title>
<![CDATA[
Connectome-constrained deep mechanistic networks predict neural responses across the fly visual system at single-neuron resolution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.11.532232v1?rss=1</link>
<description><![CDATA[
We can now measure the connectivity of every neuron in a neural circuit, but we are still blind to other biological details, including the dynamical characteristics of each neuron. The degree to which connectivity measurements alone can inform understanding of neural computation is an open question. Here we show that with only measurements of the connectivity of a biological neural network, we can predict the neural activity underlying neural computation. We constructed a model neural network with the experimentally determined connectivity for 64 cell types in the motion pathways of the fruit fly optic lobe but with unknown parameters for the single neuron and single synapse properties. We then optimized the values of these unknown parameters using techniques from deep learning, to allow the model network to detect visual motion. Our mechanistic model makes detailed experimentally testable predictions for each neuron in the connectome. We found that model predictions agreed with experimental measurements of neural activity across 24 studies. Our work demonstrates a strategy for generating detailed hypotheses about the mechanisms of neural circuit function from connectivity measurements. We show that this strategy is more likely to be successful when neurons are sparsely connected--a universally observed feature of biological neural networks across species and brain regions.
]]></description>
<dc:creator>Lappalainen, J. K.</dc:creator>
<dc:creator>Tschopp, F. D.</dc:creator>
<dc:creator>Prakhya, S.</dc:creator>
<dc:creator>McGill, M.</dc:creator>
<dc:creator>Nern, A.</dc:creator>
<dc:creator>Shinomiya, K.</dc:creator>
<dc:creator>Takemura, S.-y.</dc:creator>
<dc:creator>Gruntman, E.</dc:creator>
<dc:creator>Macke, J. H.</dc:creator>
<dc:creator>Turaga, S. C.</dc:creator>
<dc:date>2023-03-13</dc:date>
<dc:identifier>doi:10.1101/2023.03.11.532232</dc:identifier>
<dc:title><![CDATA[Connectome-constrained deep mechanistic networks predict neural responses across the fly visual system at single-neuron resolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.11.532239v1?rss=1">
<title>
<![CDATA[
Self-regulating living material with temperature-dependent light absorption 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.11.532239v1?rss=1</link>
<description><![CDATA[
Engineered living materials (ELMs) exhibit desirable characteristics of the living component, including growth and repair, and responsiveness to external stimuli. Escherichia coli are a promising constituent of ELMs because they are very tractable to genetic engineering, produce heterologous proteins readily, and grow exponentially. However, seasonal variation in ambient temperature presents a challenge in deploying ELMs outside of a laboratory environment, because E. coli growth rate is impaired both below and above 37{degrees}C. Here, we develop a genetically-encoded mechanism for autonomous temperature homeostasis in ELMs containing E. coli by engineering circuits that control the expression of a light-absorptive chromophore in response to changes in temperature. We demonstrate that below 36{degrees}C, our engineered E. coli increase in pigmentation, causing an increase in sample temperature and growth rate above non-pigmented counterparts in a model planar ELM. On the other hand, above 36{degrees}C, they decrease in pigmentation, protecting their growth compared to bacteria with temperature-independent high pigmentation. Integrating our temperature homeostasis circuit into an ELM has the potential to improve living material performance by optimizing growth and protein production in the face of seasonal temperature changes.
]]></description>
<dc:creator>Xiong, L. L.</dc:creator>
<dc:creator>Garrett, M. A.</dc:creator>
<dc:creator>Kornfield, J. A.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2023-03-12</dc:date>
<dc:identifier>doi:10.1101/2023.03.11.532239</dc:identifier>
<dc:title><![CDATA[Self-regulating living material with temperature-dependent light absorption]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.14.532527v1?rss=1">
<title>
<![CDATA[
Extracellular vesicle-localized miR-203 mediates neural crest-placode communication required for trigeminal ganglia formation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.14.532527v1?rss=1</link>
<description><![CDATA[
While interactions between neural crest and placode cells are critical for the proper formation of the trigeminal ganglion, the mechanisms underlying this process remain largely uncharacterized. Here, we show that the microRNA-(miR)203, whose epigenetic repression is required for neural crest migration, is reactivated in coalescing and condensing trigeminal ganglion cells. Overexpression of miR-203 induces ectopic coalescence of neural crest cells and increases ganglion size. Reciprocally, loss of miR-203 function in placode, but not neural crest, cells perturbs trigeminal ganglion condensation. Demonstrating intercellular communication, overexpression of miR-203 in the neural crest in vitro or in vivo represses a miR-responsive sensor in placode cells. Moreover, neural crest-secreted extracellular vesicles (EVs), visualized using pHluorin-CD63 vector, become incorporated into the cytoplasm of placode cells. Finally, RT-PCR analysis shows that small EVs isolated from condensing trigeminal ganglia are selectively loaded with miR-203. Together, our findings reveal a critical role in vivo for neural crest-placode communication mediated by sEVs and their selective microRNA cargo for proper trigeminal ganglion formation.

SIGNIFICANCE STRATEMENTCellular communication during early development plays a critical role. In this study, we demonstrate a unique role for a microRNA in cell-cell communication between the neural crest (NC) and placode cells (PC) during trigeminal ganglia (TG) formation. By utilizing loss and gain of function experiments in vivo, we demonstrate a requirement for miR-203 during cellular condensation to form the TG. We revealed that NC produces extracellular vesicles, selectively carrying miR-203, which is then taken up by the PC and regulates a sensor vector exclusively expressed in the placode. Taken together, our findings reveal a critical role in TG condensation for miR-203, produced by post-migratory NC and taken up by PC via extracellular vesicles.
]]></description>
<dc:creator>Bernardi, Y. E.</dc:creator>
<dc:creator>Sanchez-Vasquez, E.</dc:creator>
<dc:creator>Piacentino, M. L.</dc:creator>
<dc:creator>Urrutia, H.</dc:creator>
<dc:creator>Rossi, I.</dc:creator>
<dc:creator>Alcantara Saraiva, K. L.</dc:creator>
<dc:creator>Pereira-Neves, A.</dc:creator>
<dc:creator>Ramirez, M. I.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>de Miguel, N.</dc:creator>
<dc:creator>Strobl-Mazzulla, P. H.</dc:creator>
<dc:date>2023-03-15</dc:date>
<dc:identifier>doi:10.1101/2023.03.14.532527</dc:identifier>
<dc:title><![CDATA[Extracellular vesicle-localized miR-203 mediates neural crest-placode communication required for trigeminal ganglia formation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.14.532661v1?rss=1">
<title>
<![CDATA[
Single-shot 3D photoacoustic tomography using a single-element detector for ultrafast imaging of hemodynamics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.14.532661v1?rss=1</link>
<description><![CDATA[
Imaging hemodynamics is crucial for the diagnosis, treatment, and prevention of vascular diseases. However, current imaging techniques are limited due to the use of ionizing radiation or contrast agents, short penetration depth, or complex and expensive data acquisition systems. Photoacoustic tomography shows promise as a solution to these issues. However, existing photoacoustic tomography methods collect signals either sequentially or through numerous detector elements, leading to either low imaging speed or high system complexity and cost. To address these issues, here we introduce a method to capture a 3D photoacoustic image of vasculature using a single laser pulse and a single-element detector that functions as 6,400 virtual ones. Our method enables ultrafast volumetric imaging of hemodynamics in the human body at up to 1 kHz and requires only a single calibration for different objects and for long-term operations. We demonstrate 3D imaging of hemodynamics at depth in humans and small animals, capturing the variability in blood flow speeds. This concept can inspire other imaging technologies and find applications such as home-care monitoring, biometrics, point-of-care testing, and wearable monitoring.
]]></description>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Hu, P.</dc:creator>
<dc:creator>Li, L.</dc:creator>
<dc:creator>Cao, R.</dc:creator>
<dc:creator>Khadria, A.</dc:creator>
<dc:creator>Maslov, K.</dc:creator>
<dc:creator>Tong, X.</dc:creator>
<dc:creator>Zeng, Y.</dc:creator>
<dc:creator>Jiang, L.</dc:creator>
<dc:creator>Zhou, Q.</dc:creator>
<dc:creator>Wang, L.</dc:creator>
<dc:date>2023-03-15</dc:date>
<dc:identifier>doi:10.1101/2023.03.14.532661</dc:identifier>
<dc:title><![CDATA[Single-shot 3D photoacoustic tomography using a single-element detector for ultrafast imaging of hemodynamics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.17.533215v1?rss=1">
<title>
<![CDATA[
A machine-readable specification for genomics assays 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.17.533215v1?rss=1</link>
<description><![CDATA[
Understanding the structure of sequenced fragments from genomics libraries is essential for accurate read preprocessing. Currently, different assays and sequencing technologies require custom scripts and programs that do not leverage the common structure of sequence elements present in genomics libraries. We present seqspec, a machine-readable specification for libraries produced by genomics assays that facilitates standardization of preprocessing and enables tracking and comparison of genomics assays. The specification and associated seqspec command line tool is available at https://github.com/IGVF/seqspec.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2023-03-21</dc:date>
<dc:identifier>doi:10.1101/2023.03.17.533215</dc:identifier>
<dc:title><![CDATA[A machine-readable specification for genomics assays]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.20.533521v1?rss=1">
<title>
<![CDATA[
Flexible parsing and preprocessing of technical sequences with splitcode 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.20.533521v1?rss=1</link>
<description><![CDATA[
Next-generation sequencing libraries are constructed with numerous synthetic constructs such as sequencing adapters, barcodes, and unique molecular identifiers. Such sequences can be essential for interpreting results of sequencing assays, and when they contain information pertinent to an experiment, they must be processed and analyzed. We present a tool called splitcode, that enables flexible and efficient parsing, interpreting, and editing of sequencing reads. This versatile tool facilitates simple, reproducible preprocessing of reads from libraries constructed for a large array of single-cell and bulk sequencing assays.

Availability and ImplementationThe splitcode program is free, open source, and available for download at http://github.com/pachterlab/splitcode.
]]></description>
<dc:creator>Sullivan, D. K.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2023-03-23</dc:date>
<dc:identifier>doi:10.1101/2023.03.20.533521</dc:identifier>
<dc:title><![CDATA[Flexible parsing and preprocessing of technical sequences with splitcode]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.22.533729v1?rss=1">
<title>
<![CDATA[
Structure and Function of the Dot/Icm T4SS 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.22.533729v1?rss=1</link>
<description><![CDATA[
The Legionella pneumophila Dot/Icm type IV secretion system (T4SS) delivers effector proteins into host cells during infection. Despite its significance as a potential drug target, our current understanding of its atomic structure is limited to isolated subcomplexes. In this study, we used subtomogram averaging and integrative modeling to construct a nearly-complete model of the Dot/Icm T4SS accounting for seventeen protein components. We locate and provide insights into the structure and function of six new components including DotI, DotJ, DotU, IcmF, IcmT, and IcmX. We find that the cytosolic N-terminal domain of IcmF, a key protein forming a central hollow cylinder, interacts with DotU, providing insight into previously uncharacterized density. Furthermore, our model, in combination with analyses of compositional heterogeneity, explains how the cytoplasmic ATPase DotO is connected to the periplasmic complex via interactions with membrane-bound DotI/DotJ proteins. Coupled with in situ infection data, our model offers new insights into the T4SS-mediated secretion mechanism.
]]></description>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Liu, Y.</dc:creator>
<dc:creator>Maggi, S.</dc:creator>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Wang, J.</dc:creator>
<dc:creator>Carter, S. D.</dc:creator>
<dc:creator>Zhao, W.</dc:creator>
<dc:creator>Vijayrajratnam, S.</dc:creator>
<dc:creator>Vogel, J. P.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2023-03-22</dc:date>
<dc:identifier>doi:10.1101/2023.03.22.533729</dc:identifier>
<dc:title><![CDATA[Structure and Function of the Dot/Icm T4SS]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.22.533877v1?rss=1">
<title>
<![CDATA[
Probing metabolism in an E. coli-based cell-free system reveals a trade-off between transcription and translation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.22.533877v1?rss=1</link>
<description><![CDATA[
Cell-free transcription-translation (TX-TL) systems have been used for diverse applications, but their performance and scope are limited by variability and poor predictability. To understand the drivers of this variability, we explored the effects of metabolic perturbations to an E. coli Rosetta2 TX-TL system. We targeted three classes of molecules: energy molecules, in the form of nucleotide triphosphates (NTPs); central carbon "fuel" molecules, which regenerate NTPs; and magnesium ions (Mg2+). Using malachite green mRNA aptamer (MG aptamer) and destabilized enhanced Green Fluorescent Protein (deGFP) as transcriptional and translational readouts, respectively, we report the presence of a trade-off between optimizing total protein yield and optimizing total mRNA yield, as measured by integrating the area under the curve for mRNA time-course dynamics. We found that a systems position along the trade-off curve is strongly determined by Mg2+ concentration, fuel type and concentration, and cell lysate batch, and that variability can be reduced by modulating these components. Our results further suggest the trade-off arises from limitations in translation regulation and inefficient energy regeneration. This work advances our understanding of the effects of fuel and energy metabolism on TX-TL in cell-free systems and lays a foundation for improving TX-TL performance, lifetime, standardization, and prediction.

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]]></description>
<dc:creator>Kapasiawala, M.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2023-03-23</dc:date>
<dc:identifier>doi:10.1101/2023.03.22.533877</dc:identifier>
<dc:title><![CDATA[Probing metabolism in an E. coli-based cell-free system reveals a trade-off between transcription and translation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.23.533708v1?rss=1">
<title>
<![CDATA[
Flux exponent control predicts metabolic dynamics from network structure 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.23.533708v1?rss=1</link>
<description><![CDATA[
Metabolic dynamics such as stability of steady states, oscillations, lags and growth arrests in stress responses are important for microbial communities in human health, ecology, and metabolic engineering. Yet it is hard to model due to sparse data available on trajectories of metabolic fluxes. For this reason, a constraint-based approach called flux control (e.g., flux balance analysis) was invented to split metabolic systems into known stoichiometry (plant) and unknown fluxes (controller), so that data can be incorporated as refined constraints, and optimization can be used to find behaviors in scenarios of interest. However, flux control can only capture steady state fluxes well, limiting its application to scenarios with days or slower timescales. To overcome this limitation and capture dynamic fluxes, this work proposes a novel constraint-based approach, flux exponent control (FEC). FEC uses a different plant-controller split between the activities of catalytic enzymes and their regulation through binding reactions. Since binding reactions effectively regulate fluxes exponents (from previous works), this yields the rule of FEC, that cells regulate fluxes exponents, not the fluxes themselves as in flux control. In FEC, dynamic regulations of metabolic systems are solutions to optimal control problems that are computationally solvable via model predictive control. Glycolysis, which is known to have minute-timescale oscillations, is used as an example to demon-strate FEC can capture metabolism dynamics from network structure. More generally, FEC brings metabolic dynamics to the realm of control system analysis and design.
]]></description>
<dc:creator>Xiao, F.</dc:creator>
<dc:creator>Li, J. S.</dc:creator>
<dc:creator>Doyle, J. C.</dc:creator>
<dc:date>2023-03-25</dc:date>
<dc:identifier>doi:10.1101/2023.03.23.533708</dc:identifier>
<dc:title><![CDATA[Flux exponent control predicts metabolic dynamics from network structure]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.27.534286v1?rss=1">
<title>
<![CDATA[
Tools and methods for high-throughput single-cell imaging with the mother machine 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.27.534286v1?rss=1</link>
<description><![CDATA[
Despite much progress, image processing remains a significant bottleneck for high-throughput analysis of microscopy data. One popular platform for single-cell time-lapse imaging is the mother machine, which enables long-term tracking of microbial cells under precisely controlled growth conditions. While several mother machine image analysis pipelines have been developed in the past several years, adoption by a non-expert audience remains a challenge. To fill this gap, we implemented our own software, MM3, as a plugin for the multidimensional image viewer napari. napari-MM3 is a complete and modular image analysis pipeline for mother machine data, which takes advantage of the high-level interactivity of napari. Here, we give an overview of napari-MM3 and test it against several well-designed and widely-used image analysis pipelines, including BACMMAN and DeLTA. Researchers often analyze mother machine data with custom scripts using varied image analysis methods, but a quantitative comparison of the output of different pipelines has been lacking. To this end, we show that key single-cell physiological parameter correlations and distributions are robust to the choice of analysis method. However, we also find that small changes in thresholding parameters can systematically alter parameters extracted from single-cell imaging experiments. Moreover, we explicitly show that in deep learning based segmentation, "what you put is what you get" (WYPIWYG) - i.e., pixel-level variation in training data for cell segmentation can propagate to the model output and bias spatial and temporal measurements. Finally, while the primary purpose of this work is to introduce the image analysis software that we have developed over the last decade in our lab, we also provide information for those who want to implement mother-machine-based high-throughput imaging and analysis methods in their research.
]]></description>
<dc:creator>Thiermann, R.</dc:creator>
<dc:creator>Sandler, M.</dc:creator>
<dc:creator>Ahir, G.</dc:creator>
<dc:creator>Sauls, J. T.</dc:creator>
<dc:creator>Schroeder, J. W.</dc:creator>
<dc:creator>Brown, S. D.</dc:creator>
<dc:creator>Le Treut, G.</dc:creator>
<dc:creator>Si, F.</dc:creator>
<dc:creator>Li, D.</dc:creator>
<dc:creator>Wang, J.</dc:creator>
<dc:creator>Jun, S.</dc:creator>
<dc:date>2023-03-29</dc:date>
<dc:identifier>doi:10.1101/2023.03.27.534286</dc:identifier>
<dc:title><![CDATA[Tools and methods for high-throughput single-cell imaging with the mother machine]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.29.534771v1?rss=1">
<title>
<![CDATA[
The structure of the teleost Immunoglobulin M core provides insights on polymeric antibody evolution, assembly, and function 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.29.534771v1?rss=1</link>
<description><![CDATA[
Polymeric (p) immunoglobulins (Igs) serve broad functions during vertebrate immune responses. Typically, pIgs contain between two and six Ig monomers, each with two antigen binding fragments and one fragment crystallization (Fc). In addition, many pIgs assemble with a joining-chain (JC); however, the number of monomers and potential to include JC varies with species and heavy chain class. Here, we report the cryo-electron microscopy structure of IgM from a teleost (t) species, which does not encode JC. The structure revealed four tIgM Fcs linked through eight C-terminal tailpieces (Tps), which adopt a single {beta}-sandwich-like domain (Tp assembly) located between two Fcs. Remarkably, two of eight heavy chains fold uniquely, resulting in a structure distinct from mammalian IgM, which typically contains five IgM monomers, one JC and a centrally-located Tp assembly. Together with mutational analysis, structural data indicate that pIgs have evolved a range of assembly mechanisms and structures, each likely to support unique antibody effector functions.
]]></description>
<dc:creator>Lyu, M.</dc:creator>
<dc:creator>Malyutin, A.</dc:creator>
<dc:creator>Stadtmueller, B.</dc:creator>
<dc:date>2023-04-01</dc:date>
<dc:identifier>doi:10.1101/2023.03.29.534771</dc:identifier>
<dc:title><![CDATA[The structure of the teleost Immunoglobulin M core provides insights on polymeric antibody evolution, assembly, and function]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-04-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.04.04.535623v1?rss=1">
<title>
<![CDATA[
The ENCODE Uniform Analysis Pipelines 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.04.04.535623v1?rss=1</link>
<description><![CDATA[
The Encyclopedia of DNA elements (ENCODE) project is a collaborative effort to create a comprehensive catalog of functional elements in the human genome. The current database comprises more than 19000 functional genomics experiments across more than 1000 cell lines and tissues using a wide array of experimental techniques to study the chromatin structure, regulatory and transcriptional landscape of the Homo sapiens and Mus musculus genomes. All experimental data, metadata, and associated computational analyses created by the ENCODE consortium are submitted to the Data Coordination Center (DCC) for validation, tracking, storage, and distribution to community resources and the scientific community. The ENCODE project has engineered and distributed uniform processing pipelines in order to promote data provenance and reproducibility as well as allow interoperability between genomic resources and other consortia. All data files, reference genome versions, software versions, and parameters used by the pipelines are captured and available via the ENCODE Portal. The pipeline code, developed using Docker and Workflow Description Language (WDL; https://openwdl.org/) is publicly available in GitHub, with images available on Dockerhub (https://hub.docker.com), enabling access to a diverse range of biomedical researchers. ENCODE pipelines maintained and used by the DCC can be installed to run on personal computers, local HPC clusters, or in cloud computing environments via Cromwell. Access to the pipelines and data via the cloud allows small labs the ability to use the data or software without access to institutional compute clusters. Standardization of the computational methodologies for analysis and quality control leads to comparable results from different ENCODE collections - a prerequisite for successful integrative analyses.

Database URL: https://www.encodeproject.org/
]]></description>
<dc:creator>Hitz, B. C.</dc:creator>
<dc:creator>Lee, J.-W.</dc:creator>
<dc:creator>Jolanki, O.</dc:creator>
<dc:creator>Kagda, M. S.</dc:creator>
<dc:creator>Graham, K.</dc:creator>
<dc:creator>Sud, P.</dc:creator>
<dc:creator>Gabdank, I.</dc:creator>
<dc:creator>Strattan, J. S.</dc:creator>
<dc:creator>Sloan, C. A.</dc:creator>
<dc:creator>Dreszer, T.</dc:creator>
<dc:creator>Rowe, L. D.</dc:creator>
<dc:creator>Podduturi, N. R.</dc:creator>
<dc:creator>Malladi, V. S.</dc:creator>
<dc:creator>Chan, E. T.</dc:creator>
<dc:creator>Davidson, J. M.</dc:creator>
<dc:creator>Ho, M.</dc:creator>
<dc:creator>Miyasato, S.</dc:creator>
<dc:creator>Simison, M.</dc:creator>
<dc:creator>Tanaka, F.</dc:creator>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>Whaling, I.</dc:creator>
<dc:creator>Lin, K.</dc:creator>
<dc:creator>Jou, J.</dc:creator>
<dc:creator>Hong, E. L.</dc:creator>
<dc:creator>Lee, B. T.</dc:creator>
<dc:creator>Sandstrom, R.</dc:creator>
<dc:creator>Rynes, E.</dc:creator>
<dc:creator>Nelson, J.</dc:creator>
<dc:creator>Nishida, A.</dc:creator>
<dc:creator>Ingersoll, A.</dc:creator>
<dc:creator>Buckley, M.</dc:creator>
<dc:creator>Frerker, M.</dc:creator>
<dc:creator>Kim, D. S.</dc:creator>
<dc:creator>Boley, N.</dc:creator>
<dc:creator>Trout, D.</dc:creator>
<dc:creator>Dobin, A.</dc:creator>
<dc:creator>Rahmanian, S.</dc:creator>
<dc:creator>Wyman, D.</dc:creator>
<dc:creator>Balderrama-Gutierrez, G.</dc:creator>
<dc:creator>Reese, F.</dc:creator>
<dc:creator>Durand, N. C.</dc:creator>
<dc:creator>Dudchenko, O.</dc:creator>
<dc:creator>Weisz, D.</dc:creator>
<dc:creator>Rao, S. S. P.</dc:creator>
<dc:creator>Blackburn, A.</dc:creator>
<dc:creator>Gkountarou</dc:creator>
<dc:date>2023-04-06</dc:date>
<dc:identifier>doi:10.1101/2023.04.04.535623</dc:identifier>
<dc:title><![CDATA[The ENCODE Uniform Analysis Pipelines]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-04-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.04.07.536039v1?rss=1">
<title>
<![CDATA[
Evolution of neuronal cell classes and types in the vertebrate retina 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.04.07.536039v1?rss=1</link>
<description><![CDATA[
The basic plan of the retina is conserved across vertebrates, yet species differ profoundly in their visual needs (Baden et al., 2020). One might expect that retinal cell types evolved to accommodate these varied needs, but this has not been systematically studied. Here, we generated and integrated single-cell transcriptomic atlases of the retina from 17 species: humans, two non-human primates, four rodents, three ungulates, opossum, ferret, tree shrew, a teleost fish, a bird, a reptile and a lamprey. Molecular conservation of the six retinal cell classes (photoreceptors, horizontal cells, bipolar cells, amacrine cells, retinal ganglion cells [RGCs] and Muller glia) is striking, with transcriptomic differences across species correlated with evolutionary distance. Major subclasses are also conserved, whereas variation among types within classes or subclasses is more pronounced. However, an integrative analysis revealed that numerous types are shared across species based on conserved gene expression programs that likely trace back to the common ancestor of jawed vertebrates. The degree of variation among types increases from the outer retina (photoreceptors) to the inner retina (RGCs), suggesting that evolution acts preferentially to shape the retinal output. Finally, we identified mammalian orthologs of midget RGCs, which comprise >80% of RGCs in the human retina, subserve high-acuity vision, and were believed to be primate-specific (Berson, 2008); in contrast, the mouse orthologs comprise <2% of mouse RGCs. Projections both primate and mouse orthologous types are overrepresented in the thalamus, which supplies the primary visual cortex. We suggest that midget RGCs are not primate innovations, but descendants of evolutionarily ancient types that decreased in size and increased in number as primates evolved, thereby facilitating high visual acuity and increased cortical processing of visual information.
]]></description>
<dc:creator>Hahn, J.</dc:creator>
<dc:creator>Monavarfeshani, A.</dc:creator>
<dc:creator>Qiao, M.</dc:creator>
<dc:creator>Kao, A.</dc:creator>
<dc:creator>Kölsch, Y.</dc:creator>
<dc:creator>Kumar, A.</dc:creator>
<dc:creator>Kunze, V. P.</dc:creator>
<dc:creator>Rasys, A. M.</dc:creator>
<dc:creator>Richardson, R.</dc:creator>
<dc:creator>Baier, H.</dc:creator>
<dc:creator>Lucas, R. J.</dc:creator>
<dc:creator>Li, W.</dc:creator>
<dc:creator>Meister, M.</dc:creator>
<dc:creator>Trachtenberg, J. T.</dc:creator>
<dc:creator>Yan, W.</dc:creator>
<dc:creator>Peng, Y.-R.</dc:creator>
<dc:creator>Sanes, J.</dc:creator>
<dc:creator>Shekhar, K.</dc:creator>
<dc:date>2023-04-08</dc:date>
<dc:identifier>doi:10.1101/2023.04.07.536039</dc:identifier>
<dc:title><![CDATA[Evolution of neuronal cell classes and types in the vertebrate retina]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-04-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.04.11.536490v1?rss=1">
<title>
<![CDATA[
Flexibility and sensitivity in gene regulation out of equilibrium 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.04.11.536490v1?rss=1</link>
<description><![CDATA[
Cells adapt to environments and tune gene expression by controlling the concentrations of proteins and their kinetics in regulatory networks. In both eukaryotes and prokaryotes, experiments and theory increasingly attest that these networks can and do consume bio-chemical energy. How does this dissipation enable cellular behaviors unobtainable in equilibrium? This open question demands quantitative models that transcend thermodynamic equilibrium. Here we study the control of a simple, ubiquitous gene regulatory motif to explore the consequences of departing equilibrium in kinetic cycles. Employing graph theory, we find that dissipation unlocks nonmonotonicity and enhanced sensitivity of gene expression with respect to a transcription factors concentration. These features allow a single transcription factor to act as both a repressor and activator at different levels or achieve outputs with multiple concentration regions of locally-enhanced sensitivity. We systematically dissect how energetically-driving individual transitions within regulatory networks, or pairs of transitions, generates more adjustable and sensitive phenotypic responses. Our findings quantify necessary conditions and detectable consequences of energy expenditure. These richer mathematical behaviors--feasibly accessed using biological energy budgets and rates--may empower cells to accomplish sophisticated regulation with simpler architectures than those required at equilibrium.

Significance StatementGrowing theoretical and experimental evidence demonstrates that cells can (and do) spend biochemical energy while regulating their genes. Here we explore the impact of departing from equilibrium in simple regulatory cycles, and learn that beyond increasing sensitivity, dissipation can unlock more flexible input-output behaviors that are otherwise forbidden without spending energy. These more complex behaviors could enable cells to perform more sophisticated functions using simpler systems than those needed at equilibrium.
]]></description>
<dc:creator>Mahdavi, S.</dc:creator>
<dc:creator>Salmon, G. L.</dc:creator>
<dc:creator>Daghlian, P.</dc:creator>
<dc:creator>Garcia, H. G.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2023-04-13</dc:date>
<dc:identifier>doi:10.1101/2023.04.11.536490</dc:identifier>
<dc:title><![CDATA[Flexibility and sensitivity in gene regulation out of equilibrium]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-04-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.04.19.537364v1?rss=1">
<title>
<![CDATA[
D-SPIN constructs gene regulatory network models from multiplexed scRNA-seq data revealing organizing principles of cellular perturbation response 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.04.19.537364v1?rss=1</link>
<description><![CDATA[
Gene regulatory networks within cells modulate the expression of the genome in response to signals and changing environmental conditions. Reconstructions of gene regulatory networks can reveal the information processing and control principles used by cells to maintain homeostasis and execute cell-state transitions. Here, we introduce a computational framework, D-SPIN, that generates quantitative models of gene regulatory networks from single-cell mRNA-seq datasets collected across thousands of distinct perturbation conditions. D-SPIN constructs probabilistic models of regulatory interactions between genes or gene-expression programs to fit the cell state distributions under different perturbations. Using large Perturb-seq and drug-response datasets, we demonstrate that D-SPIN models reveal key regulators of cell fate decisions and the coordination of distant cellular pathways in response to gene knockdown perturbations. D-SPIN also dissects gene-level drug response mechanisms in heterogeneous cell populations, elucidating how combinations of immunomodulatory drugs acting on distinct regulators induce novel cell states through additive recruitment of gene expression programs. The D-SPIN model further predicts cell state distributions under drug dosage combinations beyond the training data. D-SPIN provides a computational framework for constructing interpretable models of gene regulatory networks to reveal principles of cellular information processing and physiological control.
]]></description>
<dc:creator>Jiang, J.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Tsou, T.</dc:creator>
<dc:creator>McGinnis, C. S.</dc:creator>
<dc:creator>Khazaei, T.</dc:creator>
<dc:creator>Zhu, Q.</dc:creator>
<dc:creator>Park, J. H.</dc:creator>
<dc:creator>Strazhnik, I.-M.</dc:creator>
<dc:creator>Hanna, J.</dc:creator>
<dc:creator>Chow, E. D.</dc:creator>
<dc:creator>Sivak, D. A.</dc:creator>
<dc:creator>Gartner, Z. J.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2023-04-21</dc:date>
<dc:identifier>doi:10.1101/2023.04.19.537364</dc:identifier>
<dc:title><![CDATA[D-SPIN constructs gene regulatory network models from multiplexed scRNA-seq data revealing organizing principles of cellular perturbation response]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-04-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.05.539530v1?rss=1">
<title>
<![CDATA[
Genomic analysis reveals the presence of emerging pathogenic Klebsiella lineages aboard the International Space Station. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.05.539530v1?rss=1</link>
<description><![CDATA[
Klebsiella species, including Klebsiella pneumoniae, Klebsiella aerogenes, and Klebsiella quasipneumoniae, are opportunistic pathogens that are known to cause infections in humans. Hypervirulent Klebsiella pneumoniae (hvKP) is a subgroup of K. pneumoniae that has gained attention due to its global dissemination and its ability to cause invasive infections in community settings amongst immunocompetent individuals as well as its increasing levels of antibiotic resistance. Our study reports the first complete genotypic analysis including mobile genetic elements (MGEs) of Klebsiella isolates from the International Space Station (ISS). The genomes of K. pneumoniae, K. aerogenes, and K. quasipneumoniae provided valuable insights into their antimicrobial resistance, virulence, thermotolerance, disinfectant resistance, and MGEs. All isolates belonged to emerging lineages with pathogenic potential, with K. quasipneumoniae ST138 presenting spatial and temporal persistence aboard the ISS, possibly due to its genotypic profile encoding for numerous resistance genes to disinfectants and heavy metals. We also report on the isolation of a yersiniabactin encoding K. pneumoniae, belonging to the emerging high-risk ST101 clone, aboard the ISS. Potential dissemination of hvKp strains on ISS could pose a putative risk to the immunocompromised crew. The presence of MGEs containing virulent loci could facilitate horizontal gene transfer to other benign microorganisms on the ISS, potentially increasing their virulence. In addition, genetic divergence from their respective lineages for some Klebsiella genomes was predicted and hypothesized to be due to the unique spaceflight environmental pressures. These findings highlight the importance of monitoring problematic microbial communities in space to understand their surviving abilities and potential impact on human health.

ImportanceThe International Space Station (ISS) is a unique hermetically sealed environment that poses environmental pressures not encountered on Earth, including microgravity and radiation While the adaptability of bacteria during spaceflight is not fully understood, recent research has suggested that it may be species and even clone specific. Given the spaceflight-induced suppression of the human immune system, it is essential to understand the genomics of potential human pathogens in spaceflight. Such understanding could provide valuable insights into species and lineages of medical astromicrobiological importance. Here, we used hybrid assembly approaches and comparative genomics to provide the first comprehensive genomic characterisation of 10 Klebsiella isolates retrieved from the ISS. Our findings revealed that K. quasipneumoniae ST138 exhibits spatial and temporal persistence aboard the ISS, with evidence of genomic divergence from the ST138 lineage on Earth. Additionally, we characterized plasmids from Klebsiella species of ISS origin, which encoded disinfectant and thermoresistance genes suggesting that these might aid adaptability. Furthermore, we identified an MGE containing a hypervirulence-associated locus belonging to a Klebsiella pneumoniae isolate of the "high risk" ST101 clone. Our work provides valuable insights into the adaptability and persistence of Klebsiella species during spaceflight, highlighting the importance of understanding the behaviour of potential pathogenic bacteria in space.
]]></description>
<dc:creator>Miliotis, G.</dc:creator>
<dc:creator>Singh, N. K.</dc:creator>
<dc:creator>McDonagh, F.</dc:creator>
<dc:creator>O'Connor, L.</dc:creator>
<dc:creator>Tuohy, A.</dc:creator>
<dc:creator>Morris, D.</dc:creator>
<dc:creator>Venkateswaran, K.</dc:creator>
<dc:date>2023-05-05</dc:date>
<dc:identifier>doi:10.1101/2023.05.05.539530</dc:identifier>
<dc:title><![CDATA[Genomic analysis reveals the presence of emerging pathogenic Klebsiella lineages aboard the International Space Station.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.06.539585v1?rss=1">
<title>
<![CDATA[
Direct androgen receptor regulation of sexually dimorphic gene expression in the mammalian kidney 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.06.539585v1?rss=1</link>
<description><![CDATA[
Mammalian organs exhibit distinct physiology, disease susceptibility and injury responses between the sexes. In the mouse kidney, sexually dimorphic gene activity maps predominantly to proximal tubule (PT) segments. Bulk RNA-seq data demonstrated sex differences were established from 4 and 8 weeks after birth under gonadal control. Hormone injection studies and genetic removal of androgen and estrogen receptors demonstrated androgen receptor (AR) mediated regulation of gene activity in PT cells as the regulatory mechanism. Interestingly, caloric restriction feminizes the male kidney. Single-nuclear multiomic analysis identified putative cis-regulatory regions and cooperating factors mediating PT responses to AR activity in the mouse kidney. In the human kidney, a limited set of genes showed conserved sex-linked regulation while analysis of the mouse liver underscored organ-specific differences in the regulation of sexually dimorphic gene expression. These findings raise interesting questions on the evolution, physiological significance, and disease and metabolic linkage, of sexually dimorphic gene activity.
]]></description>
<dc:creator>Xiong, L.</dc:creator>
<dc:creator>Liu, J.</dc:creator>
<dc:creator>Han, S. Y.</dc:creator>
<dc:creator>Koppitch, K.</dc:creator>
<dc:creator>Guo, J.-J.</dc:creator>
<dc:creator>Rommelfanger, M.</dc:creator>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>Hallgrimsdottir, I. B.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Kim, J.</dc:creator>
<dc:creator>MacLean, A. L.</dc:creator>
<dc:creator>McMahon, A.</dc:creator>
<dc:date>2023-05-06</dc:date>
<dc:identifier>doi:10.1101/2023.05.06.539585</dc:identifier>
<dc:title><![CDATA[Direct androgen receptor regulation of sexually dimorphic gene expression in the mammalian kidney]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.07.539762v1?rss=1">
<title>
<![CDATA[
High-resolution spatial multi-omics reveals cell-type specific nuclear compartments 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.07.539762v1?rss=1</link>
<description><![CDATA[
The mammalian nucleus is compartmentalized by diverse subnuclear structures. These subnuclear structures, marked by nuclear bodies and histone modifications, are often cell-type specific and affect gene regulation and 3D genome organization1-3. Understanding nuclear organization requires identifying the molecular constituents of subnuclear structures and mapping their associations with specific genomic loci in individual cells, within complex tissues. Here, we introduce two-layer DNA seqFISH+, which allows simultaneous mapping of 100,049 genomic loci, together with nascent transcriptome for 17,856 genes and a diverse set of immunofluorescently labeled subnuclear structures all in single cells in cell lines and adult mouse cerebellum. Using these multi-omics datasets, we showed that repressive chromatin compartments are more variable by cell type than active compartments. We also discovered a single exception to this rule: an RNA polymerase II (RNAPII)-enriched compartment was associated with long, cell-type specific genes (> 200kb), in a manner distinct from nuclear speckles. Further, our analysis revealed that cell-type specific facultative and constitutive heterochromatin compartments marked by H3K27me3 and H4K20me3 are enriched at specific genes and gene clusters, respectively, and shape radial chromosomal positioning and inter-chromosomal interactions in neurons and glial cells. Together, our results provide a single-cell high-resolution multi-omics view of subnuclear compartments, associated genomic loci, and their impacts on gene regulation, directly within complex tissues.
]]></description>
<dc:creator>Takei, Y.</dc:creator>
<dc:creator>Yang, Y.</dc:creator>
<dc:creator>White, J.</dc:creator>
<dc:creator>Yun, J.</dc:creator>
<dc:creator>Prasad, M.</dc:creator>
<dc:creator>Ombelets, L. J.</dc:creator>
<dc:creator>Schindler, S.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:date>2023-05-09</dc:date>
<dc:identifier>doi:10.1101/2023.05.07.539762</dc:identifier>
<dc:title><![CDATA[High-resolution spatial multi-omics reveals cell-type specific nuclear compartments]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.08.539869v1?rss=1">
<title>
<![CDATA[
Jumbo phages are active against extensively-drug-resistant eyedrop-associated Pseudomonas aeruginosa infections. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.08.539869v1?rss=1</link>
<description><![CDATA[
Antibiotic resistant bacteria present an emerging challenge to human health as the pressure instituted on the microbial world through the liberal use of antibiotics has resulted in their emergence across the globe. Those bacteria that acquire mobile genetic elements such as plasmids are especially concerning because those plasmids may be shared readily with other microbes that then can also become antibiotic resistant. Serious infections have recently been related to contamination of preservative-free eyedrops with extensively drug resistant (XDR) isolates of Pseudomonas aeruginosa, already resulting in three deaths. These drug-resistant isolates cannot be managed with most conventional antibiotics. We sought to identify alternatives to conventional antibiotics for lysis of these XDR isolates, and identified multiple bacteriophages (viruses that attack bacteria) that killed them efficiently. We found both jumbo phages (>200kb in genome size) and non-jumbo phages that were active against these isolates, the former killing more efficiently. Jumbo phages effectively killed the 3 separate XDR P. aeruginosa isolates both on solid and liquid medium. Given the ongoing nature of the XDR P. aeruginosa eyedrop outbreak, the identification of phages active against them provides physicians with several novel potential alternatives for treatment.
]]></description>
<dc:creator>Cobian-Guemes, A. G.</dc:creator>
<dc:creator>Ghatbale, P.</dc:creator>
<dc:creator>Blanc, A. N.</dc:creator>
<dc:creator>Morgan, C. J.</dc:creator>
<dc:creator>Garcia, A.</dc:creator>
<dc:creator>Leonard, J.</dc:creator>
<dc:creator>Huang, L.</dc:creator>
<dc:creator>Kovalick, G.</dc:creator>
<dc:creator>Proost, M.</dc:creator>
<dc:creator>Chiu, M.</dc:creator>
<dc:creator>Kuo, P.</dc:creator>
<dc:creator>Oh, J.</dc:creator>
<dc:creator>Karthikeyan, S.</dc:creator>
<dc:creator>Knight, R.</dc:creator>
<dc:creator>Pogliano, J.</dc:creator>
<dc:creator>Schooley, R.</dc:creator>
<dc:creator>Pride, D.</dc:creator>
<dc:date>2023-05-08</dc:date>
<dc:identifier>doi:10.1101/2023.05.08.539869</dc:identifier>
<dc:title><![CDATA[Jumbo phages are active against extensively-drug-resistant eyedrop-associated Pseudomonas aeruginosa infections.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.09.539916v1?rss=1">
<title>
<![CDATA[
Temporally organized representations of reward and risk in the human brain 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.09.539916v1?rss=1</link>
<description><![CDATA[
AO_SCPLOWBSTRACTC_SCPLOWThe value and uncertainty associated with choice alternatives constitute critical features along which decisions are made. While the neural substrates supporting reward and risk processing have been investigated, the temporal organization by which these computations are encoded remains elusive. Here we leverage the high spatiotemporal precision of intracranial electroencephalography (iEEG) to uncover how representations of decision-related computations unfold in time. We present evidence of locally distributed representations of reward and risk variables that are temporally organized across multiple regions of interest. Reward outcome representations across wide-spread regions follow a temporally cascading order along the anteroposterior axis of the brain. In contrast, expected value can be decoded from multiple regions at the same time, and error signals in both reward and risk domains reflect a mixture of sequential and parallel encoding. We highlight the role of the anterior insula in generalizing between reward prediction error (RePE) and risk prediction error (RiPE), within which the encoding of RePE in the distributed iEEG signal predicts RiPE. Together our results emphasize the utility of uncovering temporal dynamics in the human brain for understanding how computational processes critical for value-based decisions under uncertainty unfold.
]]></description>
<dc:creator>Man, V.</dc:creator>
<dc:creator>Cockburn, J.</dc:creator>
<dc:creator>Flouty, O.</dc:creator>
<dc:creator>Gander, P. E.</dc:creator>
<dc:creator>Sawada, M.</dc:creator>
<dc:creator>Kovach, C. K.</dc:creator>
<dc:creator>Kawasaki, H.</dc:creator>
<dc:creator>Oya, H.</dc:creator>
<dc:creator>Howard, M. A.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:date>2023-05-09</dc:date>
<dc:identifier>doi:10.1101/2023.05.09.539916</dc:identifier>
<dc:title><![CDATA[Temporally organized representations of reward and risk in the human brain]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.11.540424v1?rss=1">
<title>
<![CDATA[
DeCOIL: Optimization of Degenerate Codon Libraries for Machine Learning-Assisted Protein Engineering 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.11.540424v1?rss=1</link>
<description><![CDATA[
With advances in machine learning (ML)-assisted protein engineering, models based on data, biophysics, and natural evolution are being used to propose informed libraries of protein variants to explore. Synthesizing these libraries for experimental screens is a major bottleneck, as the cost of obtaining large numbers of exact gene sequences is often prohibitive. Degenerate codon (DC) libraries are a cost-effective alternative for generating combinatorial mutagenesis libraries where mutations are targeted to a handful of amino acid sites. However, existing computational methods to optimize DC libraries to include desired protein variants are not well suited to design libraries for ML-assisted protein engineering. To address these drawbacks, we present DEgenerate Codon Optimization for Informed Libraries (DeCOIL), a generalized method which directly optimizes DC libraries to be useful for protein engineering: to sample protein variants that are likely to have both high fitness and high diversity in the sequence search space. Using computational simulations and wet-lab experiments, we demonstrate that DeCOIL is effective across two specific case studies, with potential to be applied to many other use cases. DeCOIL offers several advantages over existing methods, as it is direct, easy-to-use, generalizable, and scalable. With accompanying software (https://github.com/jsunn-y/DeCOIL), DeCOIL can be readily implemented to generate desired informed libraries.



O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=114 SRC="FIGDIR/small/540424v1_ufig1.gif" ALT="Figure 1">
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]]></description>
<dc:creator>Yang, J.</dc:creator>
<dc:creator>Ducharme, J.</dc:creator>
<dc:creator>Johnston, K. E.</dc:creator>
<dc:creator>Li, F.-Z.</dc:creator>
<dc:creator>Yue, Y.</dc:creator>
<dc:creator>Arnold, F. H.</dc:creator>
<dc:date>2023-05-11</dc:date>
<dc:identifier>doi:10.1101/2023.05.11.540424</dc:identifier>
<dc:title><![CDATA[DeCOIL: Optimization of Degenerate Codon Libraries for Machine Learning-Assisted Protein Engineering]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.15.540865v1?rss=1">
<title>
<![CDATA[
The ENCODE4 long-read RNA-seq collection reveals distinct classes of transcript structure diversity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.15.540865v1?rss=1</link>
<description><![CDATA[
The majority of mammalian genes encode multiple transcript isoforms that result from differential promoter use, changes in exonic splicing, and alternative 3 end choice. Detecting and quantifying transcript isoforms across tissues, cell types, and species has been extremely challenging because transcripts are much longer than the short reads normally used for RNA-seq. By contrast, long-read RNA-seq (LR-RNA-seq) gives the complete structure of most transcripts. We sequenced 264 LR-RNA-seq PacBio libraries totaling over 1 billion circular consensus reads (CCS) for 81 unique human and mouse samples. We detect at least one full-length transcript from 87.7% of annotated human protein coding genes and a total of 200,000 full-length transcripts, 40% of which have novel exon junction chains.

To capture and compute on the three sources of transcript structure diversity, we introduce a gene and transcript annotation framework that uses triplets representing the transcript start site, exon junction chain, and transcript end site of each transcript. Using triplets in a simplex representation demonstrates how promoter selection, splice pattern, and 3 processing are deployed across human tissues, with nearly half of multitranscript protein coding genes showing a clear bias toward one of the three diversity mechanisms. Evaluated across samples, the predominantly expressed transcript changes for 74% of protein coding genes. In evolution, the human and mouse transcriptomes are globally similar in types of transcript structure diversity, yet among individual orthologous gene pairs, more than half (57.8%) show substantial differences in mechanism of diversification in matching tissues. This initial large-scale survey of human and mouse long-read transcriptomes provides a foundation for further analyses of alternative transcript usage, and is complemented by short-read and microRNA data on the same samples and by epigenome data elsewhere in the ENCODE4 collection.
]]></description>
<dc:creator>Reese, F.</dc:creator>
<dc:creator>Williams, B.</dc:creator>
<dc:creator>Balderrama-Gutierrez, G.</dc:creator>
<dc:creator>Wyman, D.</dc:creator>
<dc:creator>Celik, M. H.</dc:creator>
<dc:creator>Rebboah, E.</dc:creator>
<dc:creator>Rezaie, N.</dc:creator>
<dc:creator>Trout, D.</dc:creator>
<dc:creator>Razavi-Mohseni, M.</dc:creator>
<dc:creator>Jiang, Y.</dc:creator>
<dc:creator>Borsari, B.</dc:creator>
<dc:creator>Morabito, S.</dc:creator>
<dc:creator>Liang, H. Y.</dc:creator>
<dc:creator>McGill, C. J.</dc:creator>
<dc:creator>Rahmanian, S.</dc:creator>
<dc:creator>Sakr, J.</dc:creator>
<dc:creator>Jiang, S.</dc:creator>
<dc:creator>Zeng, W.</dc:creator>
<dc:creator>Carvalho, K.</dc:creator>
<dc:creator>Weimer, A. K.</dc:creator>
<dc:creator>Dionne, L. A.</dc:creator>
<dc:creator>McShane, A.</dc:creator>
<dc:creator>Bedi, K.</dc:creator>
<dc:creator>Elhajjajy, S. I.</dc:creator>
<dc:creator>Upchurch, S.</dc:creator>
<dc:creator>Jou, J.</dc:creator>
<dc:creator>Youngworth, I.</dc:creator>
<dc:creator>Gabdank, I.</dc:creator>
<dc:creator>Sud, P.</dc:creator>
<dc:creator>Jolanki, O.</dc:creator>
<dc:creator>Strattan, J. S.</dc:creator>
<dc:creator>Kagda, M. S.</dc:creator>
<dc:creator>Snyder, M. P.</dc:creator>
<dc:creator>Hitz, B. C.</dc:creator>
<dc:creator>Moore, J. E.</dc:creator>
<dc:creator>Weng, Z.</dc:creator>
<dc:creator>Bennett, D.</dc:creator>
<dc:creator>Reinholdt, L.</dc:creator>
<dc:creator>Ljungman, M.</dc:creator>
<dc:creator>Beer, M. A.</dc:creator>
<dc:creator>Gerstein, M. B.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Guigo, R.</dc:creator>
<dc:creator>Wold, B. J.</dc:creator>
<dc:creator>Mort</dc:creator>
<dc:date>2023-05-16</dc:date>
<dc:identifier>doi:10.1101/2023.05.15.540865</dc:identifier>
<dc:title><![CDATA[The ENCODE4 long-read RNA-seq collection reveals distinct classes of transcript structure diversity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.16.541059v1?rss=1">
<title>
<![CDATA[
Practice makes imperfect: stronger implicit interference with practice in individuals at high risk of developing Alzheimer's disease 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.16.541059v1?rss=1</link>
<description><![CDATA[
Early screening to determine patient risk of developing Alzheimers will allow better interventions and planning but necessitates accessible methods such as behavioral biomarkers. Previously, we showed that cognitively healthy older individuals whose cerebrospinal fluid amyloid / tau ratio indicates high risk of cognitive decline experienced implicit interference during a high-effort task, signaling early changes in attention. To further investigate attentions effect on implicit interference, we analyzed two experiments completed sequentially by the same high- and low-risk individuals. We hypothesized that if attention modulates interference, practice would affect the influence of implicit distractors. Indeed, while both groups experienced a strong practice effect, the association between practice and interference effects diverged between groups: stronger practice effects correlated with more implicit interference in high-risk participants, but less interference in low-risk individuals. Furthermore, low-risk individuals showed a positive correlation between implicit interference and EEG low-range alpha event-related desynchronization when switching from high-to low-load tasks. These results demonstrate how attention impacts implicit interference and highlight early differences in cognition between high- and low-risk individuals.
]]></description>
<dc:creator>Hung, S.-M.</dc:creator>
<dc:creator>Adams, S. W.</dc:creator>
<dc:creator>Molloy, C.</dc:creator>
<dc:creator>Wu, D.-A.</dc:creator>
<dc:creator>Shimojo, S.</dc:creator>
<dc:creator>Arakaki, X.</dc:creator>
<dc:date>2023-05-17</dc:date>
<dc:identifier>doi:10.1101/2023.05.16.541059</dc:identifier>
<dc:title><![CDATA[Practice makes imperfect: stronger implicit interference with practice in individuals at high risk of developing Alzheimer's disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.17.541057v1?rss=1">
<title>
<![CDATA[
Recovery of a learned behavior despite partial restoration of neuronal dynamics after chronic inactivation of inhibitory neurons 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.17.541057v1?rss=1</link>
<description><![CDATA[
Maintaining motor behaviors throughout life is crucial for an individuals survival and reproductive success. The neuronal mechanisms that preserve behavior are poorly understood. To address this question, we focused on the zebra finch, a bird that produces a highly stereotypical song after learning it as a juvenile. Using cell-specific viral vectors, we chronically silenced inhibitory neurons in the pre-motor song nucleus called the high vocal center (HVC), which caused drastic song degradation. However, after producing severely degraded vocalizations for around 2 months, the song rapidly improved, and animals could sing songs that highly resembled the original. In adult birds, single-cell RNA sequencing of HVC revealed that silencing interneurons elevated markers for microglia and increased expression of the Major Histocompatibility Complex I (MHC I), mirroring changes observed in juveniles during song learning. Interestingly, adults could restore their songs despite lesioning the lateral magnocellular nucleus of the anterior neostriatum (LMAN), a brain nucleus crucial for juvenile song learning. This suggests that while molecular mechanisms may overlap, adults utilize different neuronal mechanisms for song recovery. Chronic and acute electrophysiological recordings within HVC and its downstream target, the robust nucleus of the archistriatum (RA), revealed that neuronal activity in the circuit permanently altered with higher spontaneous firing in RA and lower in HVC compared to control even after the song had fully recovered. Together, our findings show that a complex learned behavior can recover despite extended periods of perturbed behavior and permanently altered neuronal dynamics. These results show that loss of inhibitory tone can be compensated for by recovery mechanisms partly local to the perturbed nucleus and do not require circuits necessary for learning.
]]></description>
<dc:creator>Torok, Z.</dc:creator>
<dc:creator>Luebbert, L.</dc:creator>
<dc:creator>Feldman, J.</dc:creator>
<dc:creator>Duffy, A.</dc:creator>
<dc:creator>Nevue, A.</dc:creator>
<dc:creator>Wongso, S.</dc:creator>
<dc:creator>Mello, C.</dc:creator>
<dc:creator>Fairhall, A.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Gonzalez, W.</dc:creator>
<dc:creator>Lois, C.</dc:creator>
<dc:date>2023-05-18</dc:date>
<dc:identifier>doi:10.1101/2023.05.17.541057</dc:identifier>
<dc:title><![CDATA[Recovery of a learned behavior despite partial restoration of neuronal dynamics after chronic inactivation of inhibitory neurons]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.17.541250v1?rss=1">
<title>
<![CDATA[
Studying stochastic systems biology of the cell with single-cell genomics data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.17.541250v1?rss=1</link>
<description><![CDATA[
Recent experimental developments in genome-wide RNA quantification hold considerable promise for systems biology. However, rigorously probing the biology of living cells requires a unified mathematical framework that accounts for single-molecule biological stochasticity in the context of technical variation associated with genomics assays. We review models for a variety of RNA transcription processes, as well as the encapsulation and library construction steps of microfluidics-based single-cell RNA sequencing, and present a framework to integrate these phenomena by the manipulation of generating functions. Finally, we use simulated scenarios and biological data to illustrate the implications and applications of the approach.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Vastola, J. J.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2023-05-18</dc:date>
<dc:identifier>doi:10.1101/2023.05.17.541250</dc:identifier>
<dc:title><![CDATA[Studying stochastic systems biology of the cell with single-cell genomics data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.18.541297v1?rss=1">
<title>
<![CDATA[
Neural representations of economic decision variables in human posterior parietal cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.18.541297v1?rss=1</link>
<description><![CDATA[
Decision making has been intensively studied in the posterior parietal cortex in non-human primates on a single neuron level. In humans decision making has mainly been studied with psychophysical tools or with fMRI. Here, we investigated how single neurons from human posterior parietal cortex represent numeric values informing future decisions during a complex two-player game. The tetraplegic study participant was implanted with a Utah electrode array in the anterior intraparietal area (AIP). We played a simplified variant of Black Jack with the participant while neuronal data was recorded. During the game two players are presented with numbers which are added up. Each time a number is presented the player has to decide to proceed or to stop. Once the first player stops or the score reaches a limit the turn passes on to the second player who tries to beat the score of the first player. Whoever is closer to the limit (without overshooting) wins the game. We found that many AIP neurons selectively responded to the face value of the presented number. Other neurons tracked the cumulative score or were selectively active for the upcoming decision of the study participant. Interestingly, some cells also kept track of the opponents score. Our findings show that parietal regions engaged in hand action control also represent numbers and their complex transformations. This is also the first demonstration of complex economic decisions being possible to track in single neuron activity in human AIP. Our findings show how tight are the links between parietal neural circuits underlying hand control, numerical cognition and complex decision-making.
]]></description>
<dc:creator>Klaes, C.</dc:creator>
<dc:creator>Pilacinski, A.</dc:creator>
<dc:creator>Kellis, S.</dc:creator>
<dc:creator>Aflalo, T.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Andersen, R.</dc:creator>
<dc:date>2023-05-18</dc:date>
<dc:identifier>doi:10.1101/2023.05.18.541297</dc:identifier>
<dc:title><![CDATA[Neural representations of economic decision variables in human posterior parietal cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.22.541741v1?rss=1">
<title>
<![CDATA[
Periodic hypothalamic attractor-like dynamics during the estrus cycle 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.22.541741v1?rss=1</link>
<description><![CDATA[
Cyclic changes in hormonal state are well-known to regulate mating behavior during the female reproductive cycle, but whether and how these changes affect the dynamics of neural activity in the female brain is largely unknown. The ventromedial hypothalamus, ventro-lateral subdivision (VMHvl) contains a subpopulation of VMHvlEsr1+,Npy2r- neurons that controls female sexual receptivity. Longitudinal single cell calcium imaging of these neurons across the estrus cycle revealed that overlapping but distinct subpopulations were active during proestrus (mating-accepting) vs. non-proestrus (rejecting) phases. Dynamical systems analysis of imaging data from proestrus females uncovered a dimension with slow ramping activity, which generated approximate line attractor-like dynamics in neural state space. During mating, the neural population vector progressed along this attractor as male mounting and intromission proceeded. Attractor-like dynamics disappeared in non-proestrus states and reappeared following re-entry into proestrus. They were also absent in ovariectomized females but were restored by hormone priming. These observations reveal that hypothalamic line attractor-like dynamics are associated with female sexual receptivity and can be reversibly regulated by sex hormones, demonstrating that attractor dynamics can be flexibly modulated by physiological state. They also suggest a potential mechanism for the neural encoding of female sexual arousal.
]]></description>
<dc:creator>Liu, M.</dc:creator>
<dc:creator>Nair, A.</dc:creator>
<dc:creator>Linderman, S. W.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:date>2023-05-22</dc:date>
<dc:identifier>doi:10.1101/2023.05.22.541741</dc:identifier>
<dc:title><![CDATA[Periodic hypothalamic attractor-like dynamics during the estrus cycle]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.22.541760v1?rss=1">
<title>
<![CDATA[
Identification of Biochemical Pathways Responsible for Distinct Phenotypes Using Gene Ontology Causal Activity Models 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.22.541760v1?rss=1</link>
<description><![CDATA[
Gene inactivation can affect the process(es) in which that gene acts and causally downstream ones, yielding diverse mutant phenotypes. Identifying the genetic pathways resulting in a given phenotype helps us understand how individual genes interact in a functional network. Computable representations of biological pathways include detailed process descriptions in the Reactome Knowledgebase, and causal activity flows between molecular functions in Gene Ontology-Causal Activity Models (GO-CAMs). A computational process has been developed to convert Reactome pathways to GO-CAMs. Laboratory mice are widely used models of normal and pathological human processes. We have converted human Reactome GO-CAMs to orthologous mouse GO-CAMs, as a resource to transfer pathway knowledge between humans and model organisms. These mouse GO-CAMs allowed us to define sets of genes that function in a causally connected way. To demonstrate that individual variant genes from connected pathways result in similar but distinguishable phenotypes, we used the genes in our pathway models to cross-query mouse phenotype annotations in the Mouse Genome Database (MGD). Using GO-CAM representations of two related but distinct pathways, gluconeogenesis and glycolysis, we show that individual causal paths in gene networks give rise to discrete phenotypic outcomes resulting from perturbations of glycolytic and gluconeogenic genes. The accurate and detailed descriptions of gene interactions recovered in this analysis of well-studied processes suggest that this strategy can be applied to less well-understood processes in less well-studied model systems to predict phenotypic outcomes of novel gene variants and to identify potential gene targets in altered processes.

SummaryGenes act in interconnected biological pathways, so single mutations can yield diverse phenotypes. To use the large body of mouse functional gene annotations, we converted human Gene Ontology-Causal Activity Models (GO-CAMs) of glucose metabolism to orthologous mouse GO-CAMs. We then queried phenotypes for mouse genes in these GO-CAMs and identified gene networks associated with discrete phenotypic outcomes due to perturbations of glycolysis and gluconeogenesis. This strategy can be extended to less well-understood processes and model systems to predict phenotypic outcomes.
]]></description>
<dc:creator>Hill, D.</dc:creator>
<dc:creator>Drabkin, H. J.</dc:creator>
<dc:creator>Smith, C. L.</dc:creator>
<dc:creator>Van Auken, K.</dc:creator>
<dc:creator>D'Eustachio, P.</dc:creator>
<dc:date>2023-05-24</dc:date>
<dc:identifier>doi:10.1101/2023.05.22.541760</dc:identifier>
<dc:title><![CDATA[Identification of Biochemical Pathways Responsible for Distinct Phenotypes Using Gene Ontology Causal Activity Models]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.22.541780v1?rss=1">
<title>
<![CDATA[
Effects of focused ultrasound in a "clean" mouse model of ultrasonic neuromodulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.22.541780v1?rss=1</link>
<description><![CDATA[
Recent studies on ultrasonic neuromodulation (UNM) in rodents have shown that focused ultrasound (FUS) can activate peripheral auditory pathways, leading to off-target and brain-wide excitation, which obscures the direct activation of the target area by FUS. To address this issue, we developed a new mouse model, the double transgenic Pou4f3+/DTR x Thy1-GCaMP6s, which allows for inducible deafening using diphtheria toxin and minimizes off-target effects of UNM while allowing effects on neural activity to be visualized with fluorescent calcium imaging. Using this model, we found that the auditory confounds caused by FUS can be significantly reduced or eliminated within a certain pressure range. At higher pressures, FUS can result in focal fluorescence dips at the target, elicit non-auditory sensory confounds, and damage tissue, leading to spreading depolarization. Under the acoustic conditions we tested, we did not observe direct calcium responses in the mouse cortex. Our findings provide a cleaner animal model for UNM and sonogenetics research, establish a parameter range within which off-target effects are confidently avoided, and reveal the non-auditory side effects of higher-pressure stimulation.
]]></description>
<dc:creator>Guo, H.</dc:creator>
<dc:creator>Salahshoor, H.</dc:creator>
<dc:creator>Wu, D.</dc:creator>
<dc:creator>Yoo, S.</dc:creator>
<dc:creator>Sato, T.</dc:creator>
<dc:creator>Tsao, D.</dc:creator>
<dc:creator>Shapiro, M.</dc:creator>
<dc:date>2023-05-24</dc:date>
<dc:identifier>doi:10.1101/2023.05.22.541780</dc:identifier>
<dc:title><![CDATA[Effects of focused ultrasound in a "clean" mouse model of ultrasonic neuromodulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.23.541496v1?rss=1">
<title>
<![CDATA[
Fgf10 mutant newts can regenerate normal limbs despite severe developmental hindlimb defects 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.23.541496v1?rss=1</link>
<description><![CDATA[
In the amniote limb, FGF10 is essential for limb bud initiation and outgrowth. However, whether this function is broadly conserved in tetrapods and/or involved in adult limb regeneration remains unknown. To tackle this question, we established an Fgf10 null mutant line in the newt Pleurodeles waltl which have amazing regenerative ability. While Fgf10 mutant forelimbs develop normally, the hindlimbs exhibit severe digit reduction, fail to ossify the zeugopod, and downregulate FGF target genes like Sall1, Runx1 and Hoxa11/d11. Despite these developmental defects, Fgf10 mutants were able to regenerate near-normal hindlimbs. Together, our results suggest an important role for Fgf10 in hindlimb digit formation and zeugopod ossification during development, but little or no function in regeneration, suggesting that different mechanisms operate during limb regeneration versus development.
]]></description>
<dc:creator>Suzuki, M.</dc:creator>
<dc:creator>Okumrura, A.</dc:creator>
<dc:creator>Shibata, Y.</dc:creator>
<dc:creator>Endo, T.</dc:creator>
<dc:creator>Teramoto, M.</dc:creator>
<dc:creator>Chihara, A.</dc:creator>
<dc:creator>Agata, K.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>Suzuki, K.-i. T.</dc:creator>
<dc:date>2023-05-24</dc:date>
<dc:identifier>doi:10.1101/2023.05.23.541496</dc:identifier>
<dc:title><![CDATA[Fgf10 mutant newts can regenerate normal limbs despite severe developmental hindlimb defects]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.24.542134v1?rss=1">
<title>
<![CDATA[
Dual-system avoidance: extension of a theory 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.24.542134v1?rss=1</link>
<description><![CDATA[
Our theory of positively reinforced free-operant behavior (Perez & Dickinson, 2020) assumes that responding is controlled by 2 systems. One system is sensitive to the correlation between response and reinforcement rates and controls goal-directed behavior, whereas a habitual system learns by reward prediction error. We present an extension of this theory to the aversive domain that explains why free-operant avoidance responding increases with both the experienced rate of negative reinforcement and the difference between this rate and that programmed by the avoidance schedule. The theory also assumes that the habitual component is reinforced by the acquisition of aversive inhibitory properties by the feedback stimuli generated by responding, which then act as safety signals that reinforce habit performance. Our analysis suggests that the distinction between habitual and goal-directed control of rewarded behavior can also be applied to the aversive domain.
]]></description>
<dc:creator>Perez, O. D.</dc:creator>
<dc:creator>Dickinson, A.</dc:creator>
<dc:date>2023-05-25</dc:date>
<dc:identifier>doi:10.1101/2023.05.24.542134</dc:identifier>
<dc:title><![CDATA[Dual-system avoidance: extension of a theory]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.25.542241v1?rss=1">
<title>
<![CDATA[
Projectome-defined subtypes and modular intra-hypothalamic subnetworks of peptidergic neurons 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.25.542241v1?rss=1</link>
<description><![CDATA[
The hypothalamus plays a vital role in coordinating essential neuroendocrine, autonomic, and somatomotor responses for survival and reproduction. While previous studies have explored population-level projections of hypothalamic neurons, the specific innervation patterns of individual hypothalamic axons remain unclear. To understand the organization of hypothalamic axon projections, we conducted a comprehensive reconstruction of single-cell projectomes from 7,180 mouse hypothalamic neurons expressing specific neuropeptides. Our analysis identified 31 distinct subtypes based on projectome-defined characteristics, with many exhibiting long-range axon collateral projections to multiple brain regions. Notably, these subtypes selectively targeted specific subdomains within downstream areas, either unilaterally or bilaterally. Furthermore, we observed that individual peptidergic neuronal types encompassed multiple projectome-defined subtypes, explaining their diverse functional roles. Additionally, by examining intra-hypothalamic axon projections, we uncovered six modular subnetworks characterized by enriched intramodular connections and distinct preferences for downstream targets. This modular organization of the intra-hypothalamic network likely contributes to the coordinated organization of hypothalamic outputs. In summary, our comprehensive projectome analysis reveals the organizational principles governing hypothalamic axon projections, providing a framework for understanding the neural circuit mechanisms underlying the diverse and coordinated functions of the hypothalamus.
]]></description>
<dc:creator>Jiao, Z.</dc:creator>
<dc:creator>Gao, T.</dc:creator>
<dc:creator>Wang, X.</dc:creator>
<dc:creator>Zhang, W.</dc:creator>
<dc:creator>Biglari, N.</dc:creator>
<dc:creator>Boxer, E. E.</dc:creator>
<dc:creator>Steuernagel, L.</dc:creator>
<dc:creator>Ding, X.</dc:creator>
<dc:creator>Yu, Z.</dc:creator>
<dc:creator>Li, M.</dc:creator>
<dc:creator>Hao, M.</dc:creator>
<dc:creator>Zhou, H.</dc:creator>
<dc:creator>Cao, X.</dc:creator>
<dc:creator>Li, S.</dc:creator>
<dc:creator>Jiang, T.</dc:creator>
<dc:creator>Qi, J.</dc:creator>
<dc:creator>Jia, X.</dc:creator>
<dc:creator>Feng, Z.</dc:creator>
<dc:creator>Ren, B.</dc:creator>
<dc:creator>Chen, Y.</dc:creator>
<dc:creator>Shi, X.</dc:creator>
<dc:creator>Wang, D.</dc:creator>
<dc:creator>Wang, X.</dc:creator>
<dc:creator>Han, L.</dc:creator>
<dc:creator>Liang, Y.</dc:creator>
<dc:creator>Wang, C.</dc:creator>
<dc:creator>Li, E.</dc:creator>
<dc:creator>Hu, Y.</dc:creator>
<dc:creator>Tao, Z.</dc:creator>
<dc:creator>Li, H.</dc:creator>
<dc:creator>Xiang, Y.</dc:creator>
<dc:creator>Xu, M.</dc:creator>
<dc:creator>Chang, H.-C.</dc:creator>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Xu, H.-t.</dc:creator>
<dc:creator>Yan, J.</dc:creator>
<dc:creator>Li, A.</dc:creator>
<dc:creator>Luo, Q.</dc:creator>
<dc:creator>Stoop, R.</dc:creator>
<dc:creator>Sternson, S.</dc:creator>
<dc:creator>Bruning, J. C.</dc:creator>
<dc:creator>Poo, M.-m.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:creator>Gong, H.</dc:creator>
<dc:creator>Sun, Y.</dc:creator>
<dc:creator>Xu, X.-H.</dc:creator>
<dc:date>2023-05-25</dc:date>
<dc:identifier>doi:10.1101/2023.05.25.542241</dc:identifier>
<dc:title><![CDATA[Projectome-defined subtypes and modular intra-hypothalamic subnetworks of peptidergic neurons]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.26.541240v1?rss=1">
<title>
<![CDATA[
Stoichiometric expression of messenger polycistrons by eukaryotic ribosomes (SEMPER) for compact, ratio-tunable multi-gene expression from single mRNAs 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.26.541240v1?rss=1</link>
<description><![CDATA[
Applications of mammalian synthetic biology increasingly require the ability to express multiple proteins at user-determined stoichiometries from single, compactly encoded transcripts. Here we present an approach for expressing multiple open reading frames (ORFs) from a single transcript, taking advantage of the leaky scanning model of translation initiation. In this method, adjacent ORFs are translated from a single messenger RNA at tunable ratios determined by their order in the sequence and the strength of their translation initiation sites. We call this approach Stoichiometric Expression of Messenger Polycistrons by Eukaryotic Ribosomes (SEMPER). We demonstrate the principles of this approach by expressing up to three fluorescent proteins from one plasmid in two different cell lines. We then use it to encode a stoichiometrically tuned polycistronic construct encoding gas vesicle acoustic reporter genes, showing that enforcing the optimal ratio in every cell enables efficient formation of the multi-protein complex while minimizing cellular toxicity. Finally, we demonstrate the polycistronic expression of two fluorescent proteins from single mRNAs made through in vitro transcription and delivered to cells. SEMPER will enable a broad range of applications requiring tunable expression from compact eukaryotic constructs.
]]></description>
<dc:creator>Duan, M.</dc:creator>
<dc:creator>Dev, I.</dc:creator>
<dc:creator>Lu, A.</dc:creator>
<dc:creator>You, M. Y.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2023-05-26</dc:date>
<dc:identifier>doi:10.1101/2023.05.26.541240</dc:identifier>
<dc:title><![CDATA[Stoichiometric expression of messenger polycistrons by eukaryotic ribosomes (SEMPER) for compact, ratio-tunable multi-gene expression from single mRNAs]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.29.542378v1?rss=1">
<title>
<![CDATA[
The genomic and cellular basis of biosynthetic innovation in rove beetles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.29.542378v1?rss=1</link>
<description><![CDATA[
How evolution at the cellular level potentiates change at the macroevolutionary level is a major question in evolutionary biology. With >66,000 described species, rove beetles (Staphylinidae) comprise the largest metazoan family. Their exceptional radiation has been coupled to pervasive biosynthetic innovation whereby numerous lineages bear defensive glands with diverse chemistries. Here, we combine comparative genomic and single-cell transcriptomic data from across the largest rove beetle clade, Aleocharinae. We retrace the functional evolution of two novel secretory cell types that together comprise the tergal gland--a putative catalyst behind Aleocharinaes megadiversity. We identify key genomic contingencies that were critical to the assembly of each cell type and their organ-level partnership in manufacturing the beetles defensive secretion. This process hinged on evolving a mechanism for regulated production of noxious benzoquinones that appears convergent with plant toxin release systems, and synthesis of an effective benzoquinone solvent that weaponized the total secretion. We show that this cooperative biosynthetic system arose at the Jurassic-Cretaceous boundary, and that following its establishment, both cell types underwent [~]150 million years of stasis, their chemistry and core molecular architecture maintained almost clade-wide as Aleocharinae radiated globally into tens of thousands of lineages. Despite this deep conservation, we show that the two cell types have acted as substrates for the emergence of adaptive, biochemical novelties--most dramatically in symbiotic lineages that have infiltrated social insect colonies and produce host behavior-manipulating secretions. Our findings uncover genomic and cell type evolutionary processes underlying the origin, functional conservation and evolvability of a chemical innovation in beetles.
]]></description>
<dc:creator>Kitchen, S. A.</dc:creator>
<dc:creator>Naragon, T. H.</dc:creator>
<dc:creator>Bruckner, A.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Quinodoz, S. A.</dc:creator>
<dc:creator>Badroos, J. M.</dc:creator>
<dc:creator>Viliunas, J. W.</dc:creator>
<dc:creator>Wagner, J. M.</dc:creator>
<dc:creator>Miller, D. R.</dc:creator>
<dc:creator>Yousefelahiyeh, M.</dc:creator>
<dc:creator>Antoshechkin, I. A.</dc:creator>
<dc:creator>Eldredge, K. T.</dc:creator>
<dc:creator>Pirro, S.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:creator>Davis, S. R.</dc:creator>
<dc:creator>Aardema, M. L.</dc:creator>
<dc:creator>Parker, J.</dc:creator>
<dc:date>2023-05-30</dc:date>
<dc:identifier>doi:10.1101/2023.05.29.542378</dc:identifier>
<dc:title><![CDATA[The genomic and cellular basis of biosynthetic innovation in rove beetles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.30.542205v1?rss=1">
<title>
<![CDATA[
Tuning methylation-dependent silencing dynamics by synthetic modulation of CpG density 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.30.542205v1?rss=1</link>
<description><![CDATA[
Methylation of cytosines in CG dinucleotides (CpGs) within promoters has been shown to lead to gene silencing in mammals in natural contexts. Recently, engineered recruitment of methyltransferases (DNMTs) at specific loci was shown to be sufficient to silence synthetic and endogenous gene expression through this mechanism. A critical parameter for DNA methylation-based silencing is the distribution of CpGs within the target promoter. However, how the number or density of CpGs in the target promoter affects the dynamics of silencing by DNMT recruitment has remained unclear. Here we constructed a library of promoters with systematically varying CpG content, and analyzed the rate of silencing in response to recruitment of DNMT. We observed a tight correlation between silencing rate and CpG content. Further, methylation-specific analysis revealed a constant accumulation rate of methylation at the promoter after DNMT recruitment. We identified a single CpG site between TATA box and transcription start site (TSS) that accounted for a substantial part of the difference in silencing rates between promoters with differing CpG content, indicating that certain residues play disproportionate roles in controlling silencing. Together, these results provide a library of promoters for synthetic epigenetic and gene regulation applications, as well as insights into the regulatory link between CpG content and silencing rate.
]]></description>
<dc:creator>Ma, Y.</dc:creator>
<dc:creator>Budde, M. W.</dc:creator>
<dc:creator>Zhu, J.</dc:creator>
<dc:creator>Elowitz, M.</dc:creator>
<dc:date>2023-06-01</dc:date>
<dc:identifier>doi:10.1101/2023.05.30.542205</dc:identifier>
<dc:title><![CDATA[Tuning methylation-dependent silencing dynamics by synthetic modulation of CpG density]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.31.542897v1?rss=1">
<title>
<![CDATA[
Single-cell type analysis of wing premotor circuits in the ventral nerve cord of Drosophila melanogaster 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.31.542897v1?rss=1</link>
<description><![CDATA[
To perform most behaviors, animals must send commands from higher-order processing centers in the brain to premotor circuits that reside in ganglia distinct from the brain, such as the mammalian spinal cord or insect ventral nerve cord. How these circuits are functionally organized to generate the great diversity of animal behavior remains unclear. An important first step in unraveling the organization of premotor circuits is to identify their constituent cell types and create tools to monitor and manipulate these with high specificity to assess their functions. This is possible in the tractable ventral nerve cord of the fly. To generate such a toolkit, we used a combinatorial genetic technique (split-GAL4) to create 195 sparse transgenic driver lines targeting 196 individual cell types in the ventral nerve cord. These included wing and haltere motoneurons, modulatory neurons, and interneurons. Using a combination of behavioral, developmental, and anatomical analyses, we systematically characterized the cell types targeted in our collection. In addition, we identified correspondences between the cells in this collection and a recent connectomic data set of the ventral nerve cord. Taken together, the resources and results presented here form a powerful toolkit for future investigations of neuronal circuits and connectivity of premotor circuits while linking them to behavioral outputs.
]]></description>
<dc:creator>Ehrhardt, E.</dc:creator>
<dc:creator>Whitehead, S. C.</dc:creator>
<dc:creator>Namiki, S.</dc:creator>
<dc:creator>Minegishi, R.</dc:creator>
<dc:creator>Siwanowicz, I.</dc:creator>
<dc:creator>Feng, K.</dc:creator>
<dc:creator>Otsuna, H.</dc:creator>
<dc:creator>FlyLight Project Team,</dc:creator>
<dc:creator>Meissner, G. W.</dc:creator>
<dc:creator>Stern, D.</dc:creator>
<dc:creator>Truman, J.</dc:creator>
<dc:creator>Shepherd, D.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:creator>Dickson, B. J.</dc:creator>
<dc:creator>Cohen, I.</dc:creator>
<dc:creator>Card, G. M.</dc:creator>
<dc:creator>Korff, W.</dc:creator>
<dc:date>2023-06-01</dc:date>
<dc:identifier>doi:10.1101/2023.05.31.542897</dc:identifier>
<dc:title><![CDATA[Single-cell type analysis of wing premotor circuits in the ventral nerve cord of Drosophila melanogaster]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.05.543764v1?rss=1">
<title>
<![CDATA[
The Genetic Architecture of Dietary Iron Overload and Associated Pathology in Mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.05.543764v1?rss=1</link>
<description><![CDATA[
Tissue iron overload is a frequent pathologic finding in multiple disease states including non-alcoholic fatty liver disease (NAFLD), neurodegenerative disorders, cardiomyopathy, diabetes, and some forms of cancer. The role of iron, as a cause or consequence of disease progression and observed phenotypic manifestations, remains controversial. In addition, the impact of genetic variation on iron overload related phenotypes is unclear, and the identification of genetic modifiers is incomplete. Here, we used the Hybrid Mouse Diversity Panel (HMDP), consisting of over 100 genetically distinct mouse strains optimized for genome-wide association studies and systems genetics, to characterize the genetic architecture of dietary iron overload and pathology. Dietary iron overload was induced by feeding male mice (114 strains, 6-7 mice per strain on average) a high iron diet for six weeks, and then tissues were collected at 10-11 weeks of age. Liver metal levels and gene expression were measured by ICP-MS/ICP-AES and RNASeq, and lipids were measured by colorimetric assays. FaST-LMM was used for genetic mapping, and Metascape, WGCNA, and Mergeomics were used for pathway, module, and key driver bioinformatics analyses. Mice on the high iron diet accumulated iron in the liver, with a 6.5 fold difference across strain means. The iron loaded diet also led to a spectrum of copper deficiency and anemia, with liver copper levels highly positively correlated with red blood cell count, hemoglobin, and hematocrit. Hepatic steatosis of various severity was observed histologically, with 52.5 fold variation in triglyceride levels across the strains. Liver triglyceride and iron mapped most significantly to an overlapping locus on chromosome 7 that has not been previously associated with either trait. Based on network modeling, significant key drivers for both iron and triglyceride accumulation are involved in cholesterol biosynthesis and oxidative stress management. To make the full data set accessible and useable by others, we have made our data and analyses available on a resource website.

Author summaryThe response to a high iron diet is determined in part by genetic factors. We now report the responses to such a diet in a diverse set of inbred strains of mice, known as the Hybrid Mouse Diversity Panel, that enables high resolution genetic mapping and systems genetics analyses. The levels of iron in the liver varied about >5 fold across the strains, with genetic variation explaining up to 74% of the variation in liver iron. Pathologies included copper deficiency, anemia, and fatty liver, with liver triglycerides varying over 50 fold among the strains. Genetic mapping and network modeling identified significant genetic loci and pathways underlying the response to diet.
]]></description>
<dc:creator>Fuqua, B. K.</dc:creator>
<dc:creator>Moses, L.</dc:creator>
<dc:creator>McLachlan, S.</dc:creator>
<dc:creator>Pan, C.</dc:creator>
<dc:creator>Davis, R. C.</dc:creator>
<dc:creator>Hui, S. T.</dc:creator>
<dc:creator>Che, N.</dc:creator>
<dc:creator>Zhou, Z.</dc:creator>
<dc:creator>Ng, C.</dc:creator>
<dc:creator>Charugundla, S.</dc:creator>
<dc:creator>Blencowe, M.</dc:creator>
<dc:creator>Saleem, Z.</dc:creator>
<dc:creator>Miikeda, A.</dc:creator>
<dc:creator>Ozdemir, B.</dc:creator>
<dc:creator>Hui, C.</dc:creator>
<dc:creator>Li, T.</dc:creator>
<dc:creator>Stolin, C. L.</dc:creator>
<dc:creator>Kozuch, M.</dc:creator>
<dc:creator>Zhou, J.</dc:creator>
<dc:creator>Page, K.</dc:creator>
<dc:creator>Irimagawa, H.</dc:creator>
<dc:creator>Ku, N.</dc:creator>
<dc:creator>Taraszka, K.</dc:creator>
<dc:creator>LaPierre, N.</dc:creator>
<dc:creator>Killilea, D. W.</dc:creator>
<dc:creator>Frazer, D. M.</dc:creator>
<dc:creator>Yang, X.</dc:creator>
<dc:creator>Eskin, E.</dc:creator>
<dc:creator>Vulpe, C. D.</dc:creator>
<dc:creator>Lusis, A. J.</dc:creator>
<dc:date>2023-06-07</dc:date>
<dc:identifier>doi:10.1101/2023.06.05.543764</dc:identifier>
<dc:title><![CDATA[The Genetic Architecture of Dietary Iron Overload and Associated Pathology in Mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.05.543769v1?rss=1">
<title>
<![CDATA[
SPIDR: a highly multiplexed method for mapping RNA-protein interactions uncovers a potential mechanism for selective translational suppression upon cellular stress 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.05.543769v1?rss=1</link>
<description><![CDATA[
RNA binding proteins (RBPs) play crucial roles in regulating every stage of the mRNA life cycle and mediating non-coding RNA functions. Despite their importance, the specific roles of most RBPs remain unexplored because we do not know what specific RNAs most RBPs bind. Current methods, such as crosslinking and immunoprecipitation followed by sequencing (CLIP-seq), have expanded our knowledge of RBP-RNA interactions but are generally limited by their ability to map only one RBP at a time. To address this limitation, we developed SPIDR (Split and Pool Identification of RBP targets), a massively multiplexed method to simultaneously profile global RNA binding sites of dozens to hundreds of RBPs in a single experiment. SPIDR employs split-pool barcoding coupled with antibody-bead barcoding to increase the throughput of current CLIP methods by two orders of magnitude. SPIDR reliably identifies precise, single-nucleotide RNA binding sites for diverse classes of RBPs simultaneously. Using SPIDR, we explored changes in RBP binding upon mTOR inhibition and identified that 4EBP1 acts as a dynamic RBP that selectively binds to 5-untranslated regions of specific translationally repressed mRNAs only upon mTOR inhibition. This observation provides a potential mechanism to explain the specificity of translational regulation controlled by mTOR signaling. SPIDR has the potential to revolutionize our understanding of RNA biology and both transcriptional and post-transcriptional gene regulation by enabling rapid, de novo discovery of RNA-protein interactions at an unprecedented scale.
]]></description>
<dc:creator>Wolin, E.</dc:creator>
<dc:creator>Guo, J. K.</dc:creator>
<dc:creator>Blanco, M. R.</dc:creator>
<dc:creator>Perez, A. A.</dc:creator>
<dc:creator>Goronzy, I. N.</dc:creator>
<dc:creator>Abdou, A. A.</dc:creator>
<dc:creator>Gorhe, D.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:creator>Jovanovic, M.</dc:creator>
<dc:date>2023-06-07</dc:date>
<dc:identifier>doi:10.1101/2023.06.05.543769</dc:identifier>
<dc:title><![CDATA[SPIDR: a highly multiplexed method for mapping RNA-protein interactions uncovers a potential mechanism for selective translational suppression upon cellular stress]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.06.543925v1?rss=1">
<title>
<![CDATA[
Lineage motifs: developmental modules for control of cell type proportions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.06.543925v1?rss=1</link>
<description><![CDATA[
In multicellular organisms, cell types must be produced and maintained in appropriate proportions. One way this is achieved is through committed progenitor cells that produce specific sets of descendant cell types. However, cell fate commitment is probabilistic in most contexts, making it difficult to infer progenitor states and understand how they establish overall cell type proportions. Here, we introduce Lineage Motif Analysis (LMA), a method that recursively identifies statistically overrepresented patterns of cell fates on lineage trees as potential signatures of committed progenitor states. Applying LMA to published datasets reveals spatial and temporal organization of cell fate commitment in zebrafish and rat retina and early mouse embryo development. Comparative analysis of vertebrate species suggests that lineage motifs facilitate adaptive evolutionary variation of retinal cell type proportions. LMA thus provides insight into complex developmental processes by decomposing them into simpler underlying modules.
]]></description>
<dc:creator>Tran, M.</dc:creator>
<dc:creator>Askary, A.</dc:creator>
<dc:creator>Elowitz, M.</dc:creator>
<dc:date>2023-06-07</dc:date>
<dc:identifier>doi:10.1101/2023.06.06.543925</dc:identifier>
<dc:title><![CDATA[Lineage motifs: developmental modules for control of cell type proportions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.07.543722v1?rss=1">
<title>
<![CDATA[
Cell type-specific contributions to a persistent aggressive internal state in female Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.07.543722v1?rss=1</link>
<description><![CDATA[
Persistent internal states are important for maintaining survival-promoting behaviors, such as aggression. In female Drosophila melanogaster, we have previously shown that individually activating either aIPg or pC1d cell types can induce aggression. Here we investigate further the individual roles of these cholinergic, sexually dimorphic cell types, and the reciprocal connections between them, in generating a persistent aggressive internal state. We find that a brief 30-second optogenetic stimulation of aIPg neurons was sufficient to promote an aggressive internal state lasting at least 10 minutes, whereas similar stimulation of pC1d neurons did not. While we previously showed that stimulation of pC1e alone does not evoke aggression, persistent behavior could be promoted through simultaneous stimulation of pC1d and pC1e, suggesting an unexpected synergy of these cell types in establishing a persistent aggressive state. Neither aIPg nor pC1d show persistent neuronal activity themselves, implying that the persistent internal state is maintained by other mechanisms. Moreover, inactivation of pC1d did not significantly reduce aIPg-evoked persistent aggression arguing that the aggressive state did not depend on pC1d-aIPg recurrent connectivity. Our results suggest the need for alternative models to explain persistent female aggression.
]]></description>
<dc:creator>Chiu, H.</dc:creator>
<dc:creator>Robie, A. A.</dc:creator>
<dc:creator>Branson, K. M.</dc:creator>
<dc:creator>Vippa, T.</dc:creator>
<dc:creator>Epstein, S.</dc:creator>
<dc:creator>Rubin, G. M.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:creator>Schretter, C. E.</dc:creator>
<dc:date>2023-06-07</dc:date>
<dc:identifier>doi:10.1101/2023.06.07.543722</dc:identifier>
<dc:title><![CDATA[Cell type-specific contributions to a persistent aggressive internal state in female Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.09.544292v1?rss=1">
<title>
<![CDATA[
Development of cell-free transcription-translation systems in three soil Pseudomonads 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.09.544292v1?rss=1</link>
<description><![CDATA[
In vitro transcription-translation (TX-TL) can enable faster engineering of biological systems. This speed-up can be significant, especially in difficult-to-transform chassis. This work shows the successful development of TX-TL systems using three soil-derived wild-type Pseudomonads known to promote plant growth: Pseudomonas synxantha, Pseudomonas chlororaphis, and Pseudomonas aureofaciens. One, P. synxantha, was further characterized. A lysate test of P. synxantha showed a maximum protein yield of 2.5 M at 125 proteins per DNA template and a maximum protein synthesis rate of 20 nM/min. A set of different constitutive promoters driving mNeonGreen expression were tested in TX-TL and integrated into the genome, showing similar normalized strengths for in vivo and in vitro fluorescence. This correspondence between the TX-TL derived promoter strength and the in vivo promoter strength indicates these lysate-based cell-free systems can be used to characterize and engineer biological parts without genome integration, enabling a faster designbuild-test cycle.
]]></description>
<dc:creator>Meyerowitz, J. T.</dc:creator>
<dc:creator>Larsson, E. M.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2023-06-09</dc:date>
<dc:identifier>doi:10.1101/2023.06.09.544292</dc:identifier>
<dc:title><![CDATA[Development of cell-free transcription-translation systems in three soil Pseudomonads]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.13.541482v1?rss=1">
<title>
<![CDATA[
Functional glycoproteomics by integrated network assembly and partitioning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.13.541482v1?rss=1</link>
<description><![CDATA[
The post-translational modification (PTM) of proteins by O-linked {beta}-N-acetyl-D-glucosamine (O-GlcNAcylation) is widespread across the proteome during the lifespan of all multicellular organisms. However, nearly all functional studies have focused on individual protein modifications, overlooking the multitude of simultaneous O-GlcNAcylation events that work together to coordinate cellular activities. Here, we describe Networking of Interactors and SubstratEs (NISE), a novel, systems-level approach to rapidly and comprehensively monitor O-GlcNAcylation across the proteome. Our method integrates affinity purification-mass spectrometry (AP-MS) and site-specific chemoproteomic technologies with network generation and unsupervised partitioning to connect potential upstream regulators with downstream targets of O-GlcNAcylation. The resulting network provides a data-rich framework that reveals both conserved activities of O-GlcNAcylation such as epigenetic regulation as well as tissue-specific functions like synaptic morphology. Beyond O-GlcNAc, this holistic and unbiased systems-level approach provides a broadly applicable framework to study PTMs and discover their diverse roles in specific cell types and biological states.
]]></description>
<dc:creator>Griffin, M. E.</dc:creator>
<dc:creator>Thompson, J. W.</dc:creator>
<dc:creator>Xiao, Y.</dc:creator>
<dc:creator>Sweredoski, M. J.</dc:creator>
<dc:creator>Jensen, E. H.</dc:creator>
<dc:creator>Koldobskaya, Y.</dc:creator>
<dc:creator>Schacht, A. L.</dc:creator>
<dc:creator>Kim, T. D.</dc:creator>
<dc:creator>Choudhry, P.</dc:creator>
<dc:creator>Lomenick, B.</dc:creator>
<dc:creator>Garbis, S. D.</dc:creator>
<dc:creator>Moradian, A.</dc:creator>
<dc:creator>Hsieh-Wilson, L. C.</dc:creator>
<dc:date>2023-06-14</dc:date>
<dc:identifier>doi:10.1101/2023.06.13.541482</dc:identifier>
<dc:title><![CDATA[Functional glycoproteomics by integrated network assembly and partitioning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/205104v1?rss=1">
<title>
<![CDATA[
The representation of colored objects in macaque color patches 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/205104v1?rss=1</link>
<description><![CDATA[
An important question about color vision is: how does the brain represent the color of an object? The recent discovery of "color patches" in macaque inferotemporal (IT) cortex, the part of brain responsible for object recognition, makes this problem experimentally tractable. Here we record neurons in three color patches, middle color patch CLC (central lateral color patch), and two anterior color patches ALC (anterior lateral color patch) and AMC (anterior medial color patch), while presenting images of objects systematically varied in hue. We found that all three patches contain high concentrations of hue-selective cells, and the three patches use distinct computational strategies to represent colored objects: while all three patches multiplex hue and shape information, shape-invariant hue information is much stronger in anterior color patches ALC/AMC than CLC; furthermore, hue and object shape specifically for primate faces/bodies are over-represented in AMC but not in the other two patches.
]]></description>
<dc:creator>Chang, L.</dc:creator>
<dc:creator>Bao, P.</dc:creator>
<dc:creator>Tsao, D.</dc:creator>
<dc:date>2017-10-19</dc:date>
<dc:identifier>doi:10.1101/205104</dc:identifier>
<dc:title><![CDATA[The representation of colored objects in macaque color patches]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/207035v1?rss=1">
<title>
<![CDATA[
Distinct glycosaminoglycan chain length and sulfation patterns required for cellular uptake of Tau, Aβ, and α-Synuclein 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/207035v1?rss=1</link>
<description><![CDATA[
Transcellular propagation of aggregate "seeds" has been proposed to mediate progression of neurodegenerative diseases in tauopathies and -synucleinopathies. We have previously determined that tau and -synuclein aggregates bind heparan sulfate proteoglycans (HSPGs) on the cell surface. This mediates uptake and intracellular seeding. The specificity and mode of binding to HSPGs has been unknown. We used modified heparins to determine the size and sulfation requirements of glycosaminoglycan (GAGs) binding to aggregates in biochemical and cell uptake and seeding assays. Aggregates of tau require a precise GAG architecture with defined sulfate moieties in the N- and 6-O-positions, whereas -synuclein and A{beta} rely slightly more on overall charge on the GAGs. To determine the genetic requirements for aggregate uptake, we individually knocked out the major genes of the HSPG synthesis pathway using CRISPR/Cas9 in HEK293T cells. Knockout of EXT1, EXT2 and EXTL3, N-sulfotransferase (NDST1), and 6-O-sulfotransferase (HS6ST2) significantly reduced tau uptake. -Synuclein was not sensitive to HS6ST2 knockout. Good correlation between pharmacologic and genetic manipulation of GAG binding by tau and -synuclein indicates specificity that may help elucidate a path to mechanism-based inhibition of transcellular propagation of pathology.
]]></description>
<dc:creator>Stopschinski, B. E.</dc:creator>
<dc:creator>Holmes, B. B.</dc:creator>
<dc:creator>Miller, G. M.</dc:creator>
<dc:creator>Vaquer-Alicea, J.</dc:creator>
<dc:creator>Hsieh-Wilson, L. C.</dc:creator>
<dc:creator>Diamond, M. I.</dc:creator>
<dc:date>2017-10-21</dc:date>
<dc:identifier>doi:10.1101/207035</dc:identifier>
<dc:title><![CDATA[Distinct glycosaminoglycan chain length and sulfation patterns required for cellular uptake of Tau, Aβ, and α-Synuclein]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/207936v1?rss=1">
<title>
<![CDATA[
How Cognitive and Reactive Fear Circuits Optimize Escape Decisions in Humans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/207936v1?rss=1</link>
<description><![CDATA[
Flight initiation distance (FID), the distance at which an organism flees from an approaching threat, is an ecological metric of cost-benefit functions of escape decisions. We adapted the FID paradigm to investigate how fast or slow attacking  virtual predators constrain escape decisions. We show that rapid escape decisions rely on  reactive fear circuits in the periaqueductal gray and midcingulate cortex (MCC), while protracted escape decisions, defined by larger buffer zones, were associated with  cognitive fear circuits which include posterior cingulate cortex, hippocampus and the ventromedial prefrontal cortex, circuits implicated in strategic avoidance and behavioral flexibility. Using a Bayesian Decision Model, we further show that optimization of escape decisions under rapid flight were localized to the MCC, a region involved in adaptive motor control, while the hippocampus is implicated in optimizing decisions that update and control slower escape initiation. These results demonstrate an unexplored link between defensive survival circuits and their role in adaptive escape decisions.nnSignificanceHumans, like other animals, have evolved a set of circuits whose primary function is survival. In the case of predation, these circuits include  reactive fear circuits involved in fast and immediate escape decisions and  cognitive fear circuits that are involved in the conscious feeling of threat as well as slow strategic escape. Using neuroimaging combined with computational modeling, we support this differentiation of fear circuits by showing that fast escape decisions are elicited by the periaqueductal gray and MCC, regions involved in reactive flight. Conversely, slower escape decisions rely on the hippocampus, posterior cingulate cortex and prefrontal cortex, a circuit implicated in behavioral flexibility. These results support the role of the defensive survival circuitry in escape decisions and a separation of fear into reactive and cognitive circuits.
]]></description>
<dc:creator>Qi, S.</dc:creator>
<dc:creator>Sun, J.</dc:creator>
<dc:creator>Guo, F.</dc:creator>
<dc:creator>Daw, N.</dc:creator>
<dc:creator>Hassabis, D.</dc:creator>
<dc:creator>Mobbs, D.</dc:creator>
<dc:date>2017-10-23</dc:date>
<dc:identifier>doi:10.1101/207936</dc:identifier>
<dc:title><![CDATA[How Cognitive and Reactive Fear Circuits Optimize Escape Decisions in Humans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/208686v1?rss=1">
<title>
<![CDATA[
Metabolic Interactions Between Dynamic Bacterial Subpopulations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/208686v1?rss=1</link>
<description><![CDATA[
Within multi-species microbial communities, individual species are known to occupy distinct metabolic niches. By contrast, it has remained largely unclear whether and how metabolic specialization occurs within clonal bacterial populations. The possibility of such metabolic specialization in clonal populations raises several questions: Does specialization occur, and if it does, which metabolic processes are involved? How is specialization coordinated? How rapidly do cells switch between states? And finally, what functions might metabolic specialization provide? One potential function of metabolic specialization could be to manage overflow metabolites such as acetate, which presents a toxic challenge due to low pH, and protective pH-neutral overflow metabolites. Here we show that exponentially dividing Bacillus subtilis cultures divide into distinct interacting metabolic subpopulations including one population that produces acetate, and another population that differentially expresses metabolic genes for the production of acetoin, a pH-neutral storage molecule. These subpopulations grew at distinct rates, and cells switched dynamically between states, with acetate influencing the relative sizes of the different subpopulations. These results show that clonal populations can use metabolic specialization to control the environment through a process of dynamic, environmentally-sensitive state-switching.
]]></description>
<dc:creator>Rosenthal, A. Z.</dc:creator>
<dc:creator>Qi, Y.</dc:creator>
<dc:creator>Hormoz, S.</dc:creator>
<dc:creator>Park, J.</dc:creator>
<dc:creator>Li, S. H.-J.</dc:creator>
<dc:creator>Elowitz, M.</dc:creator>
<dc:date>2017-10-25</dc:date>
<dc:identifier>doi:10.1101/208686</dc:identifier>
<dc:title><![CDATA[Metabolic Interactions Between Dynamic Bacterial Subpopulations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/210138v1?rss=1">
<title>
<![CDATA[
The self-organization of plant microtubules in three dimensions enables stable cortical localization and sensitivity to external cues 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/210138v1?rss=1</link>
<description><![CDATA[
Many cell functions rely on the ability of microtubules to self-organize as complex networks. In plants, cortical microtubules are essential to determine cell shape as they guide the deposition of cellulose microfibrils, and thus control mechanical anisotropy in the cell wall. Here we analyze how, in turn, cell shape may influence microtubule behavior. Using a computational model of microtubules enclosed in a three-dimensional space, We show that the microtubule network has spontaneous configurations that could explain many experimental observations without resorting to specific regulation. In particular, we find that the preferred localization of microtubules at the cortex emerges from directional persistence of the microtubules, combined with their growth mode. We identified microtubule parameters that seem relatively insensitive to cell shape, such as length or number. In contrast, microtubule array anisotropy depends strongly on local curvature of the cell surface and global orientation follows robustly the longest axis of the cell. Lastly, we found that the network is capable of reorienting toward weak external directional cues. Altogether our simulations show that the microtubule network is a good transducer of weak external polarity, while at the same time, it easily reaches stable global configurations.nnAuthor summaryPlants exhibit an astonishing diversity in architecture and shape. A key to such diversity is the ability of their cells to coordinate and grow to reach a broad spectrum of sizes and shapes. Cell growth in plants is guided by the microtubule cytoskeleton. Here, we seek to understand how microtubules self-organize close to the cell surface. We build upon previous two-dimensional models and we consider microtubules as lines growing in three dimensions, accounting for interactions between microtubules or between microtubules and the cell surface. We show that microtubule arrays are able to adapt to various cell shapes and to reorient in response to factors such as signals or environment. Altogether, our results help to understand how the microtubule cytoskeleton contributes to the diversity of plant shapes and to how these shapes adapt to environment.
]]></description>
<dc:creator>Mirabet, V.</dc:creator>
<dc:creator>Krupinski, P.</dc:creator>
<dc:creator>Hamant, O.</dc:creator>
<dc:creator>Meyerowitz, E.</dc:creator>
<dc:creator>Jonsson, H.</dc:creator>
<dc:creator>Boudaoud, A.</dc:creator>
<dc:date>2017-10-27</dc:date>
<dc:identifier>doi:10.1101/210138</dc:identifier>
<dc:title><![CDATA[The self-organization of plant microtubules in three dimensions enables stable cortical localization and sensitivity to external cues]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/210310v1?rss=1">
<title>
<![CDATA[
Summarizing Performance for Genome Scale Measurement of miRNA: Reference Samples and Metrics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/210310v1?rss=1</link>
<description><![CDATA[
BackgroundThe potential utility of microRNA as biomarkers for early detection of cancer and other diseases is being investigated with genome-scale profiling of differentially expressed microRNA. Processes for measurement assurance are critical components of genome-scale measurements. Here, we evaluated the utility of a set of total RNA samples, designed with between-sample differences in the relative abundance of miRNAs, as process controls.nnResultsThree pure total human RNA samples (brain, liver, and placenta) and two different mixtures of these components were evaluated as measurement assurance control samples on multiple measurement systems at multiple sites and over multiple rounds. In silico modeling of mixtures provided benchmark values for comparison with physical mixtures. Biomarker development laboratories using next-generation sequencing (NGS) or genome-scale hybridization assays participated in the study and returned data from the samples using their routine workflows. Multiplexed and single assay reverse-transcription PCR (RT-PCR) was used to confirm in silico predicted sample differences. Data visualizations and summary metrics for genome-scale miRNA profiling assessment were developed using this dataset, and a range of performance was observed. These metrics have been incorporated into an online data analysis pipeline and provide a convenient dashboard view of results from experiments following the described design. The website also serves as a repository for the accumulation of performance values providing new participants in the project an opportunity to learn what may be achievable with similar measurement processes.nnConclusionsThe set of reference samples used in this study provides benchmark values suitable for assessing genome-scale miRNA profiling processes. Incorporation of these metrics into an online resource allows laboratories to periodically evaluate their performance and assess any changes introduced into their measurement process.
]]></description>
<dc:creator>Pine, P. S.</dc:creator>
<dc:creator>Lund, S. P.</dc:creator>
<dc:creator>Parsons, J. R.</dc:creator>
<dc:creator>Vang, L. K.</dc:creator>
<dc:creator>Mahabal, A. A.</dc:creator>
<dc:creator>Cinquini, L.</dc:creator>
<dc:creator>Kelly, S. C.</dc:creator>
<dc:creator>Kincaid, H.</dc:creator>
<dc:creator>Crichton, D. J.</dc:creator>
<dc:creator>Spira, A.</dc:creator>
<dc:creator>Liu, G.</dc:creator>
<dc:creator>Gower, A. C.</dc:creator>
<dc:creator>Pass, H. I.</dc:creator>
<dc:creator>Goparaju, C.</dc:creator>
<dc:creator>Dubinett, S. M.</dc:creator>
<dc:creator>Krysan, K.</dc:creator>
<dc:creator>Stass, S. A.</dc:creator>
<dc:creator>Kukuruga, D.</dc:creator>
<dc:creator>Van Keuren-Jensen, K.</dc:creator>
<dc:creator>Courtright-Lim, A.</dc:creator>
<dc:creator>Thompson, K. L.</dc:creator>
<dc:creator>Rosenzweig, B. A.</dc:creator>
<dc:creator>Sorbara, L.</dc:creator>
<dc:creator>Srivastava, S.</dc:creator>
<dc:creator>Salit, M. L.</dc:creator>
<dc:date>2017-10-27</dc:date>
<dc:identifier>doi:10.1101/210310</dc:identifier>
<dc:title><![CDATA[Summarizing Performance for Genome Scale Measurement of miRNA: Reference Samples and Metrics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/211201v1?rss=1">
<title>
<![CDATA[
A High-Resolution Probabilistic In Vivo Atlas of Human Subcortical Brain Nuclei 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/211201v1?rss=1</link>
<description><![CDATA[
Recent advances in magnetic resonance imaging (MRI) methods, including data acquisition, pre-processing and analysis, have enabled research on the contributions of subcortical brain nuclei to human cognition and behavior. At the same time, these developments have led to an increasing need for a high-resolution probabilistic in-vivo anatomical atlas of subcortical nuclei. In order to fill this gap, we constructed high spatial resolution, three-dimensional templates, using joint high accuracy diffeomorphic registration of T1- and T2- weighted structural images from 168 typical adults between 22 and 35 years old. In these templates, many tissue boundaries are clearly visible, which would otherwise be impossible to delineate in data from individual studies. The resulting delineation provides a more accurate parcellation of subcortical nuclei than current histology-based atlases. We further created a companion library of software tools for atlas development, to offer an open and evolving resource for the creation of a crowd-sourced in-vivo probabilistic anatomical atlas of the human brain.
]]></description>
<dc:creator>Pauli, W. M.</dc:creator>
<dc:creator>Nili, A. N.</dc:creator>
<dc:creator>Tyszka, J. M.</dc:creator>
<dc:date>2017-10-30</dc:date>
<dc:identifier>doi:10.1101/211201</dc:identifier>
<dc:title><![CDATA[A High-Resolution Probabilistic In Vivo Atlas of Human Subcortical Brain Nuclei]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/214486v1?rss=1">
<title>
<![CDATA[
Causal Mapping of Emotion Networks in the Human Brain: Framework and Preliminary Findings 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/214486v1?rss=1</link>
<description><![CDATA[
Emotions involve many cortical and subcortical regions, prominently including the amygdala. It remains unknown how these multiple network components interact, and it remains unknown how they cause the behavioral, autonomic, and experiential effects of emotions. Here we describe a framework for combining a novel technique, concurrent electrical stimulation with fMRI (es-fMRI), together with a novel analysis, inferring causal structure from fMRI data (causal discovery). We outline a research program for investigating human emotion with these new tools, and provide initial findings from two large resting-state datasets as well as case studies in neurosurgical patients with electrical stimulation of the amygdala. The overarching goal is to use causal discovery methods on fMRI data to infer causal graphical models of how brain regions interact, and then to further constrain these models with direct stimulation of specific brain regions and concurrent fMRI. We conclude by discussing limitations and future extensions. The approach could yield anatomical hypotheses about brain connectivity, motivate rational strategies for treating mood disorders with deep brain stimulation, and could be extended to animal studies that use combined optogenetic fMRI.
]]></description>
<dc:creator>Dubois, J.</dc:creator>
<dc:creator>Oya, H.</dc:creator>
<dc:creator>Tyszka, J. M.</dc:creator>
<dc:creator>Howard, M.</dc:creator>
<dc:creator>Eberhardt, F.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:date>2017-11-05</dc:date>
<dc:identifier>doi:10.1101/214486</dc:identifier>
<dc:title><![CDATA[Causal Mapping of Emotion Networks in the Human Brain: Framework and Preliminary Findings]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/214619v1?rss=1">
<title>
<![CDATA[
Multidimensional quantitative analysis of mRNA expression within intact vertebrate embryos 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/214619v1?rss=1</link>
<description><![CDATA[
For decades, in situ hybridization methods have been essential tools for studies of vertebrate development and disease, as they enable qualitative analyses of mRNA expression in an anatomical context. Quantitative mRNA analyses typically sacrifice the anatomy, relying on embryo microdissection, dissociation, cell sorting, and/or homogenization. Here, we eliminate the tradeoff between quantitation and anatomical context, using multiplexed in situ hybridization chain reaction (HCR) to perform accurate and precise relative quantitation of mRNA expression with subcellular resolution within whole-mount vertebrate embryos. Gene expression can be queried in two directions: read-out from anatomical space to expression space reveals co-expression relationships in selected regions of the specimen; conversely, read-in from multidimensional expression space to anatomical space reveals those anatomical locations in which selected gene co-expression relationships occur. As we demonstrate by examining gene circuits underlying somitogenesis, quantitative read-out and read-in analyses provide the strengths of flow cytometry expression analyses, but by preserving subcellular anatomical context, they enable iterative bi-directional queries that open a new era for in situ hybridization.nnSUMMARYMultiplexed in situ hybridization chain reaction (HCR) enables quantitative multidimensional analyses of developmental gene expression with subcellular resolution in an anatomical context.
]]></description>
<dc:creator>Trivedi, V.</dc:creator>
<dc:creator>Choi, H. M. T.</dc:creator>
<dc:creator>Fraser, S. E.</dc:creator>
<dc:creator>Pierce, N. A.</dc:creator>
<dc:date>2017-11-06</dc:date>
<dc:identifier>doi:10.1101/214619</dc:identifier>
<dc:title><![CDATA[Multidimensional quantitative analysis of mRNA expression within intact vertebrate embryos]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/215129v1?rss=1">
<title>
<![CDATA[
Predicting personality traits from resting-state fMRI 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/215129v1?rss=1</link>
<description><![CDATA[
Personality neuroscience aims to find associations between brain measures and personality traits. Findings to date have been severely limited by a number of factors, including small sample size and omission of out-of-sample prediction. We capitalized on the recent availability of a large database, together with the emergence of specific criteria for best practices in neuroimaging studies of individual differences. We analyzed resting-state functional magnetic resonance imaging data from 884 young healthy adults in the Human Connectome Project (HCP) database. We attempted to predict personality traits from the "Big Five", as assessed with the NEO-FFI test, using individual functional connectivity matrices. After regressing out potential confounds (such as age, sex, handedness and fluid intelligence), we used a cross-validated framework, together with test-retest replication (across two sessions of resting-state fMRI for each subject), to quantify how well the neuroimaging data could predict each of the five personality factors. We tested three different (published) denoising strategies for the fMRI data, two inter-subject alignment and brain parcellation schemes, and three different linear models for prediction. As measurement noise is known to moderate statistical relationships, we performed final prediction analyses using average connectivity across both imaging sessions (1 h of data), with the analysis pipeline that yielded the highest predictability overall. Across all results (test/retest; 3 denoising strategies; 2 alignment schemes; 3 models), Openness to experience emerged as the only reliably predicted personality factor. Using the full hour of resting-state data and the best pipeline, we could predict Openness to experience (NEOFAC_O: r=0.24, R2=0.024) almost as well as we could predict the score on a 24-item intelligence test (PMAT24_A_CR: r=0.26, R2=0.044). Other factors (Extraversion, Neuroticism, Agreeableness and Conscientiousness) yielded weaker predictions across results that were not statistically significant under permutation testing. We also derived two superordinate personality factors ("" and "{beta}") from a principal components analysis of the NEO-FFI factor scores, thereby reducing noise and enhancing the precision of these measures of personality. We could account for 5% of the variance in the {beta} superordinate factor (r=0.27, R2=0.050), which loads highly on Openness to experience. We conclude with a discussion of the potential for predicting personality from neuroimaging data and make specific recommendations for the field.
]]></description>
<dc:creator>Dubois, J.</dc:creator>
<dc:creator>Galdi, P.</dc:creator>
<dc:creator>Han, Y.</dc:creator>
<dc:creator>Paul, L. K.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:date>2017-11-07</dc:date>
<dc:identifier>doi:10.1101/215129</dc:identifier>
<dc:title><![CDATA[Predicting personality traits from resting-state fMRI]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/219683v1?rss=1">
<title>
<![CDATA[
Higher-order inter-chromosomal hubs shape 3-dimensional genome organization in the nucleus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/219683v1?rss=1</link>
<description><![CDATA[
Eukaryotic genomes are packaged into a 3-dimensional structure in the nucleus of each cell. There are currently two distinct views of genome organization that are derived from different technologies. The first view, derived from genome-wide proximity ligation methods (e.g. Hi-C), suggests that genome organization is largely organized around chromosomes. The second view, derived from in situ imaging, suggests a central role for nuclear bodies. Yet, because microscopy and proximity-ligation methods measure different aspects of genome organization, these two views remain poorly reconciled and our overall understanding of how genomic DNA is organized within the nucleus remains incomplete. Here, we develop Split-Pool Recognition of Interactions by Tag Extension (SPRITE), which moves away from proximity-ligation and enables genome-wide detection of higher-order DNA interactions within the nucleus. Using SPRITE, we recapitulate known genome structures identified by Hi-C and show that the contact frequencies measured by SPRITE strongly correlate with the 3-dimensional distances measured by microscopy. In addition to known structures, SPRITE identifies two major hubs of inter-chromosomal interactions that are spatially arranged around the nucleolus and nuclear speckles, respectively. We find that the majority of genomic regions exhibit preferential spatial association relative to one of these nuclear bodies, with regions that are highly transcribed by RNA Polymerase II organizing around nuclear speckles and transcriptionally inactive and centromere-proximal regions organizing around the nucleolus. Together, our results reconcile the two distinct pictures of nuclear structure and demonstrate that nuclear bodies act as inter-chromosomal hubs that shape the overall 3-dimensional packaging of genomic DNA in the nucleus.
]]></description>
<dc:creator>Quinodoz, S. A.</dc:creator>
<dc:creator>Ollikainen, N.</dc:creator>
<dc:creator>Tabak, B.</dc:creator>
<dc:creator>Palla, A.</dc:creator>
<dc:creator>Schmidt, J. M.</dc:creator>
<dc:creator>Detmar, E.</dc:creator>
<dc:creator>Lai, M.</dc:creator>
<dc:creator>Shishkin, A.</dc:creator>
<dc:creator>Bhat, P.</dc:creator>
<dc:creator>Trinh, V.</dc:creator>
<dc:creator>Aznauryan, E.</dc:creator>
<dc:creator>Russell, P.</dc:creator>
<dc:creator>Cheng, C.</dc:creator>
<dc:creator>Jovanovic, M.</dc:creator>
<dc:creator>Chow, A.</dc:creator>
<dc:creator>McDonel, P.</dc:creator>
<dc:creator>Garber, M.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:date>2017-11-18</dc:date>
<dc:identifier>doi:10.1101/219683</dc:identifier>
<dc:title><![CDATA[Higher-order inter-chromosomal hubs shape 3-dimensional genome organization in the nucleus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/220244v1?rss=1">
<title>
<![CDATA[
Length and time scales of cell-cell signaling circuits in agar 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/220244v1?rss=1</link>
<description><![CDATA[
A community of genetically heterogeneous cells embedded in an unmixed medium allows for sophisticated operations by retaining spatial differentiation and coordinating division-of-labor. To establish the principles of engineering reliable cell-cell communication in a heterogeneous environment, we examined how circuit parameters and spatial placement affect the range of length and time scales over which simple communication circuits interact. We constructed several "sender" and "receiver" strains with quorum-sensing signaling circuits. The sender cell colony produces acyl homoserine lactones (AHL), which diffuse across the semisolid medium. The receiver cell colony detects these signal molecules and reports by fluorescence. We have found that a single colony of one sender variant is sufficient to induce receiver response at more than 1.5cm separation. Furthermore, AHL degradase expression in receiver colonies produces a signal threshold effect and reduces the response level in subsequent receiver colonies. Finally, our investigation on the spatial placement of colonies gave rise to the design of a multicellular long-range communication array consisting of two alternating colony types. Its signal response successfully propagated colony-by-colony along a six-colony array spanning 4.8cm at a transmission velocity of 12.8 hours per colony or 0.075cm per hour. In addition, we have developed a reaction-diffusion model that recreates the observed behaviors of the many performed experiments using data-informed parameter estimates of signal diffusion, gene expression, and nutrient consumption. These results demonstrate that a mixed community of colonies can enable new patterning programs, and the corresponding model will facilitate the rational design of complex communication networks.
]]></description>
<dc:creator>Doong, J.</dc:creator>
<dc:creator>Parkin, J.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2017-11-18</dc:date>
<dc:identifier>doi:10.1101/220244</dc:identifier>
<dc:title><![CDATA[Length and time scales of cell-cell signaling circuits in agar]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/222042v1?rss=1">
<title>
<![CDATA[
Hard Limits And Performance Tradeoffs In A Class Of Sequestration Feedback Systems 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/222042v1?rss=1</link>
<description><![CDATA[
Feedback regulation is pervasive in biology at both the organismal and cellular level. In this article, we explore the properties of a particular biomolecular feedback mechanism implemented using the sequestration binding of two molecules. Our work develops an analytic framework for understanding the hard limits, performance tradeoffs, and architectural properties of this simple model of biological feedback control. Using tools from control theory, we show that there are simple parametric relationships that determine both the stability and the performance of these systems in terms of speed, robustness, steady-state error, and leakiness. These findings yield a holistic understanding of the behavior of sequestration feedback and contribute to a more general theory of biological control systems.
]]></description>
<dc:creator>Olsman, N.</dc:creator>
<dc:creator>Baetica, A.-A.</dc:creator>
<dc:creator>Xiao, F.</dc:creator>
<dc:creator>Leong, Y. P.</dc:creator>
<dc:creator>Doyle, J.</dc:creator>
<dc:creator>Murray, R.</dc:creator>
<dc:date>2017-11-20</dc:date>
<dc:identifier>doi:10.1101/222042</dc:identifier>
<dc:title><![CDATA[Hard Limits And Performance Tradeoffs In A Class Of Sequestration Feedback Systems]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/225904v1?rss=1">
<title>
<![CDATA[
Improving the annotation of the Heterorhabditis bacteriophora genome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/225904v1?rss=1</link>
<description><![CDATA[
Genome assembly and annotation remains an exacting task. As the tools available for these tasks improve, it is useful to return to data produced with earlier instances to assess their credibility and correctness. The entomopathogenic nematode Heterorhabditis bacteriophora is widely used to control insect pests in horticulture. The genome sequence for this species was reported to encode an unusually high proportion of unique proteins and a paucity of secreted proteins compared to other related nematodes. We revisited the H. bacteriophora genome assembly and gene predictions to ask whether these unusual characteristics were biological or methodological in origin. We mapped an independent resequencing dataset to the genome and used the blobtools pipeline to identify potential contaminants. While present (0.2% of the genome span, 0.4% of predicted proteins), assembly contamination was not significant. Re-prediction of the gene set using BRAKER1 and published transcriptome data generated a predicted proteome that was very different from the published one. The new gene set had a much reduced complement of unique proteins, better completeness values that were in line with other related species genomes, and an increased number of proteins predicted to be secreted. It is thus likely that methodological issues drove the apparent uniqueness of the initial H. bacteriophora genome annotation and that similar contamination and misannotation issues affect other published genome assemblies.
]]></description>
<dc:creator>McLean, F.</dc:creator>
<dc:creator>Berger, D.</dc:creator>
<dc:creator>Laetsch, D.</dc:creator>
<dc:creator>Schwartz, H.</dc:creator>
<dc:creator>Blaxter, M.</dc:creator>
<dc:date>2017-11-30</dc:date>
<dc:identifier>doi:10.1101/225904</dc:identifier>
<dc:title><![CDATA[Improving the annotation of the Heterorhabditis bacteriophora genome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/227462v1?rss=1">
<title>
<![CDATA[
An open resource for nonhuman primate imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/227462v1?rss=1</link>
<description><![CDATA[
Non-human primate neuroimaging is a rapidly growing area of research that promises to transform and scale translational and cross-species comparative neuroscience.nnUnfortunately, the technological and methodological advances of the past two decades have outpaced the accrual of data, which is particularly challenging given the relatively few centers that have the necessary facilities and capabilities. The PRIMate Data Exchange (PRIME-DE) addresses this challenge by aggregating independently acquired non-human primate magnetic resonance imaging (MRI) datasets and openly sharing them via the International Neuroimaging Data-sharing Initiative (INDI). Here, we present the rationale, design and procedures for the PRIME-DE consortium, as well as the initial release, consisting of 13 independent data collections aggregated across 11 sites (total = 98 macaque monkeys). We also outline the unique pitfalls and challenges that should be considered in the analysis of the non-human primate MRI datasets, including providing automated quality assessment of the contributed datasets.
]]></description>
<dc:creator>Milham, M.</dc:creator>
<dc:creator>Ai, L.</dc:creator>
<dc:creator>Koo, B.</dc:creator>
<dc:creator>Xu, T.</dc:creator>
<dc:creator>Balezeau, F.</dc:creator>
<dc:creator>Baxter, M. G.</dc:creator>
<dc:creator>Croxson, P. L.</dc:creator>
<dc:creator>Damatac, C. G.</dc:creator>
<dc:creator>Harel, N.</dc:creator>
<dc:creator>Freiwald, W.</dc:creator>
<dc:creator>Griffiths, T. D.</dc:creator>
<dc:creator>Everling, S.</dc:creator>
<dc:creator>Jung, B.</dc:creator>
<dc:creator>Kastner, S.</dc:creator>
<dc:creator>Leopold, D. A.</dc:creator>
<dc:creator>Mars, R. B.</dc:creator>
<dc:creator>Menon, R. S.</dc:creator>
<dc:creator>Messinger, A.</dc:creator>
<dc:creator>Morrison, J. H.</dc:creator>
<dc:creator>Nacef, J.</dc:creator>
<dc:creator>Nagy, J.</dc:creator>
<dc:creator>Rios, M. O.</dc:creator>
<dc:creator>Petkov, C. I.</dc:creator>
<dc:creator>Pinsk, M.</dc:creator>
<dc:creator>Poirier, C.</dc:creator>
<dc:creator>Rajimehr, R.</dc:creator>
<dc:creator>Rushworth, M. F.</dc:creator>
<dc:creator>Russ, B. E.</dc:creator>
<dc:creator>Schmid, M.</dc:creator>
<dc:creator>Schwiedrzik, C. M.</dc:creator>
<dc:creator>Sallet, J.</dc:creator>
<dc:creator>Seidlitz, J.</dc:creator>
<dc:creator>Ungerleider, L.</dc:creator>
<dc:creator>Thiele, A.</dc:creator>
<dc:creator>Tsao, D.</dc:creator>
<dc:creator>Yacoub, E.</dc:creator>
<dc:creator>Ye, F.</dc:creator>
<dc:creator>Zarco, W.</dc:creator>
<dc:creator>Margulies, D. S.</dc:creator>
<dc:creator>Schroeder, C. E.</dc:creator>
<dc:date>2017-11-30</dc:date>
<dc:identifier>doi:10.1101/227462</dc:identifier>
<dc:title><![CDATA[An open resource for nonhuman primate imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/227504v1?rss=1">
<title>
<![CDATA[
MetaRiPPquest: A Peptidogenomics Approach for the Discovery of Ribosomally Synthesized and Post-translationally Modified Peptides 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/227504v1?rss=1</link>
<description><![CDATA[
Ribosomally synthesized and post-translationally modified peptides (RiPPs) are an important class of natural products that include many antibiotics and a variety of other bioactive compounds. While recent breakthroughs in RiPP discovery raised the challenge of developing new algorithms for their analysis, peptidogenomic-based identification of RiPPs by combining genome/metagenome mining with analysis of tandem mass spectra remains an open problem. We present here MetaRiPPquest, a software tool for addressing this challenge that is compatible with large-scale screening platforms for natural product discovery. After searching millions of spectra in the Global Natural Products Social (GNPS) molecular networking infrastructure against just six genomic and metagenomic datasets, MetaRiPPquest identified 27 known and discovered 5 novel RiPP natural products.
]]></description>
<dc:creator>Mohimani, H.</dc:creator>
<dc:creator>Gurevich, A.</dc:creator>
<dc:creator>Alexander, K. L.</dc:creator>
<dc:creator>Naman, C. B.</dc:creator>
<dc:creator>Leao, T.</dc:creator>
<dc:creator>Glukhov, E.</dc:creator>
<dc:creator>Moss, N. A.</dc:creator>
<dc:creator>Luzzatto Knaan, T.</dc:creator>
<dc:creator>Vargas, F.</dc:creator>
<dc:creator>Nothias, L.-F.</dc:creator>
<dc:creator>Singh, N. K.</dc:creator>
<dc:creator>Sanders, J. G.</dc:creator>
<dc:creator>Benitez, R. A. S.</dc:creator>
<dc:creator>Thompson, L. R.</dc:creator>
<dc:creator>Hamid, M. N.</dc:creator>
<dc:creator>Morton, J. T.</dc:creator>
<dc:creator>Mikheenko, A.</dc:creator>
<dc:creator>Shlemov, A.</dc:creator>
<dc:creator>Korobeynikov, A.</dc:creator>
<dc:creator>Friedberg, I.</dc:creator>
<dc:creator>Knight, R.</dc:creator>
<dc:creator>Venkateswaran, K.</dc:creator>
<dc:creator>Gerwick, W.</dc:creator>
<dc:creator>Gerwick, L.</dc:creator>
<dc:creator>Dorrestein, P. C.</dc:creator>
<dc:creator>Pevzner, P. A.</dc:creator>
<dc:date>2017-12-03</dc:date>
<dc:identifier>doi:10.1101/227504</dc:identifier>
<dc:title><![CDATA[MetaRiPPquest: A Peptidogenomics Approach for the Discovery of Ribosomally Synthesized and Post-translationally Modified Peptides]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-12-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/227991v1?rss=1">
<title>
<![CDATA[
Drosophila have distinct activity-gated pathways that mediate attraction and aversion to CO2 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/227991v1?rss=1</link>
<description><![CDATA[
Carbon dioxide is a volatile and broad signal of many organic processes, and serves as a convenient cue for insects in search of blood hosts1-6, flowers7, decaying matter8-11, communal nests12, fruit13, and wildfires14. Curiously, although Drosophila melanogaster feed on yeast that produce CO2 and ethanol during fermentation, laboratory experiments suggest that flies actively avoid CO215-25. Here, we resolve this paradox by showing that both flying and walking fruit flies do actually find CO2 attractive, but only when they are in an active state associated with foraging. Aversion at low activity levels may be an adaptation to avoid CO2-seeking-parasites, or succumbing to respiratory acidosis in the presence of high concentrations of CO2 that are occasionally found in nature26,27. In contrast to CO2, flies are attracted to ethanol in all behavioral states, and invest twice as much time searching near ethanol compared to CO2. These behavioral differences reflect the fact that whereas CO2 is a generated by many natural processes, ethanol is a unique signature of yeast fermentation. Using genetic tools, we determined that the evolutionarily ancient ionotropic co-receptor IR25a is required for both CO2 and ethanol attraction, and that the receptors previously identified for CO2 avoidance are not involved. Our study lays the foundation for future research to determine the neural circuits underlying both state- and odorant-dependent decision making in Drosophila.
]]></description>
<dc:creator>van Breugel, F.</dc:creator>
<dc:creator>Huda, A.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:date>2017-12-03</dc:date>
<dc:identifier>doi:10.1101/227991</dc:identifier>
<dc:title><![CDATA[Drosophila have distinct activity-gated pathways that mediate attraction and aversion to CO2]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-12-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/231696v1?rss=1">
<title>
<![CDATA[
The functional organization of descending sensory-motor pathways in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/231696v1?rss=1</link>
<description><![CDATA[
In most animals, the brain controls the body via a set of descending neurons (DNs) that traverse the neck and terminate in post-cranial regions of the nervous system. This critical neural population is thought to activate, maintain and modulate locomotion and other behaviors. Although individual members of this cell class have been well-studied across species ranging from insects to primates, little is known about the overall connectivity pattern of DNs as a population. We undertook a systematic anatomical investigation of descending neurons in the fruit fly, Drosophila melanogaster, and created a collection of over 100 transgenic lines targeting individual cell types. Our methods allowed us to describe the morphology of roughly half of an estimated 400 DNs and create a comprehensive map of connectivity between the sensory neuropils in the brain and the motor neuropils in the ventral nerve cord. Like the vertebrate spinal cord, our results show that the fly nerve cord is a highly organized, layered system of neuropils, an organization that reflects the fact that insects are capable of two largely independent means of locomotion - walking and fight - using distinct sets of appendages. Our results reveal the basic functional map of descending pathways in flies and provide tools for systematic interrogation of sensory-motor circuits.
]]></description>
<dc:creator>Namiki, S.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:creator>Wong, A. M.</dc:creator>
<dc:creator>Korff, W.</dc:creator>
<dc:creator>Card, G. M.</dc:creator>
<dc:date>2017-12-11</dc:date>
<dc:identifier>doi:10.1101/231696</dc:identifier>
<dc:title><![CDATA[The functional organization of descending sensory-motor pathways in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-12-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/234211v1?rss=1">
<title>
<![CDATA[
Ultrasonic Neuromodulation Causes Widespread Cortical Activation via an Indirect Auditory Mechanism 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/234211v1?rss=1</link>
<description><![CDATA[
Ultrasound has received widespread attention as an emerging technology for targeted, non-invasive neuromodulation based on its ability to evoke electrophysiological and motor responses in animals. However, little is known about the spatiotemporal pattern of ultrasound-induced brain activity that could drive these responses. Here, we address this question by combining focused ultrasound with wide-field optical imaging of calcium signals in transgenic mice. Surprisingly, we find cortical activity patterns consistent with indirect activation of auditory pathways rather than direct neuromodulation at the ultrasound focus. Ultrasound-induced activity is similar to that evoked by audible sound. Furthermore, both ultrasound and audible sound elicit motor responses consistent with a startle reflex, with both responses reduced by chemical deafening. These findings reveal an indirect auditory mechanism for ultrasound-induced cortical activity and movement requiring careful consideration in future development of ultrasonic neuromodulation as a tool in neuroscience research.
]]></description>
<dc:creator>Sato, T.</dc:creator>
<dc:creator>Shapiro, M.</dc:creator>
<dc:creator>Tsao, D.</dc:creator>
<dc:date>2017-12-14</dc:date>
<dc:identifier>doi:10.1101/234211</dc:identifier>
<dc:title><![CDATA[Ultrasonic Neuromodulation Causes Widespread Cortical Activation via an Indirect Auditory Mechanism]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-12-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/236455v1?rss=1">
<title>
<![CDATA[
Theoretical Analysis of Inducer and Operator Binding for Cyclic-AMP Receptor Protein Mutants 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/236455v1?rss=1</link>
<description><![CDATA[
Allosteric transcription factors undergo binding events both at their inducer binding sites as well as at distinct DNA binding domains, and it is often difficult to disentangle the structural and functional consequences of these two classes of interactions. In this work, we compare the ability of two statistical mechanical models - the Monod-Wyman-Changeux (MWC) and the Koshland-Nemethy-Filmer (KNF) models of protein conformational change - to characterize the multi-step activation mechanism of the broadly acting cyclic-AMP receptor protein (CRP). We first consider the allosteric transition resulting from cyclic-AMP binding to CRP, then analyze how CRP binds to its operator, and finally investigate the ability of CRP to activate gene expression. In light of these models, we examine data from a beautiful recent experiment that created a single-chain version of the CRP homodimer, thereby enabling each subunit to be mutated separately. Using this construct, six mutants were created using all possible combinations of the wild type subunit, a D53H mutant subunit, and an S62F mutant subunit. We demonstrate that both the MWC and KNF models can explain the behavior of all six mutants using a small, self-consistent set of parameters. In comparing the results, we find that the MWC model slightly outperforms the KNF model in the quality of its fits, but more importantly the parameters inferred by the MWC model are more in line with structural knowledge of CRP. In addition, we discuss how the conceptual framework developed here for CRP enables us to not merely analyze data retrospectively, but has the predictive power to determine how combinations of mutations will interact, how double mutants will behave, and how each construct would regulate gene expression.
]]></description>
<dc:creator>Einav, T.</dc:creator>
<dc:creator>Duque, J.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2017-12-19</dc:date>
<dc:identifier>doi:10.1101/236455</dc:identifier>
<dc:title><![CDATA[Theoretical Analysis of Inducer and Operator Binding for Cyclic-AMP Receptor Protein Mutants]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-12-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/239335v1?rss=1">
<title>
<![CDATA[
A systematic approach for dissecting the molecular mechanisms of transcriptional regulation in bacteria 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/239335v1?rss=1</link>
<description><![CDATA[
Gene regulation is one of the most ubiquitous processes in biology. But while the catalog of bacterial genomes continues to expand rapidly, we remain ignorant about how almost all of the genes in these genomes are regulated. At present, characterizing the molecular mechanisms by which individual regulatory sequences operate requires focused efforts using low-throughput methods. Here we show how a combination of massively parallel reporter assays, mass spectrometry, and information-theoretic modeling can be used to dissect bacterial promoters in a systematic and scalable way. We demonstrate this method on both well-studied and previously uncharacterized promoters in the enteric bacterium Escherichia coli. In all cases we recover nucleotide-resolution models of promoter mechanism. For some promoters, including previously unannotated ones, the approach allowed us to further extract quantitative biophysical models describing input-output relationships. This method opens up the possibility of exhaustively dissecting the mechanisms of promoter function in E. coli and a wide range of other bacteria.
]]></description>
<dc:creator>Belliveau, N. M.</dc:creator>
<dc:creator>Barnes, S. L.</dc:creator>
<dc:creator>Ireland, W. T.</dc:creator>
<dc:creator>Jones, D. L.</dc:creator>
<dc:creator>Sweredoski, M.</dc:creator>
<dc:creator>Moradian, A.</dc:creator>
<dc:creator>Hess, S.</dc:creator>
<dc:creator>Kinney, J. B.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2017-12-23</dc:date>
<dc:identifier>doi:10.1101/239335</dc:identifier>
<dc:title><![CDATA[A systematic approach for dissecting the molecular mechanisms of transcriptional regulation in bacteria]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-12-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/241406v1?rss=1">
<title>
<![CDATA[
Acoustically Targeted Chemogenetics for Noninvasive Control of Neural Circuits 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/241406v1?rss=1</link>
<description><![CDATA[
Neurological and psychiatric diseases often involve the dysfunction of specific neural circuits in particular regions of the brain. Existing treatments, including drugs and implantable brain stimulators, aim to modulate the activity of these circuits, but are typically not cell type-specific, lack spatial targeting or require invasive procedures. Here, we introduce an approach to modulating neural circuits noninvasively with spatial, cell-type and temporal specificity. This approach, called acoustically targeted chemogenetics, or ATAC, uses transient ultrasonic opening of the blood brain barrier to transduce neurons at specific locations in the brain with virally-encoded engineered G-protein-coupled receptors, which subsequently respond to systemically administered bio-inert compounds to activate or inhibit the activity of these neurons. We demonstrate this concept in mice by using ATAC to noninvasively modify and subsequently activate or inhibit excitatory neurons within the hippocampus, showing that this enables pharmacological control of memory formation. This technology allows a brief, noninvasive procedure to make one or more specific brain regions capable of being selectively modulated using orally bioavailable compounds, thereby overcoming some of the key limitations of conventional brain therapies.
]]></description>
<dc:creator>Szablowski, J. O.</dc:creator>
<dc:creator>Lue, B.</dc:creator>
<dc:creator>Lee-Gosselin, A.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2018-01-01</dc:date>
<dc:identifier>doi:10.1101/241406</dc:identifier>
<dc:title><![CDATA[Acoustically Targeted Chemogenetics for Noninvasive Control of Neural Circuits]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-01-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/243352v1?rss=1">
<title>
<![CDATA[
Observing the Cell in Its Native State: Imaging Subcellular Dynamics in Multicellular Organisms 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/243352v1?rss=1</link>
<description><![CDATA[
True physiological imaging of subcellular dynamics requires studying cells within their parent organisms, where all the environmental cues that drive gene expression, and hence the phenotypes we actually observe, are present. A complete understanding also requires volumetric imaging of the cell and its surroundings at high spatiotemporal resolution without inducing undue stress on either. We combined lattice light sheet microscopy with two-channel adaptive optics to achieve, across large multicellular volumes, noninvasive aberration-free imaging of subcellular processes, including endocytosis, organelle remodeling during mitosis, and the migration of axons, immune cells, and metastatic cancer cells in vivo. The technology reveals the phenotypic diversity within cells across different organisms and developmental stages, and may offer insights into how cells harness their intrinsic variability to adapt to different physiological environments.nnOne Sentence SummaryCombining lattice light sheet microscopy with adaptive optics enables high speed, high resolution in vivo 3D imaging of dynamic processes inside cells under physiological conditions within their parent organisms.
]]></description>
<dc:creator>Liu, T.-l.</dc:creator>
<dc:creator>Upadhyayula, S.</dc:creator>
<dc:creator>Milkie, D. E.</dc:creator>
<dc:creator>Singh, V.</dc:creator>
<dc:creator>Wang, K.</dc:creator>
<dc:creator>Swinburne, I. A.</dc:creator>
<dc:creator>Mosaliganti, K. R.</dc:creator>
<dc:creator>Collin, Z. M.</dc:creator>
<dc:creator>Hiscock, T. W.</dc:creator>
<dc:creator>Shea, J.</dc:creator>
<dc:creator>Kohrman, A. Q.</dc:creator>
<dc:creator>Medwig, T. N.</dc:creator>
<dc:creator>Dambournet, D.</dc:creator>
<dc:creator>Forster, R.</dc:creator>
<dc:creator>Cunniff, B.</dc:creator>
<dc:creator>Ruan, Y.</dc:creator>
<dc:creator>Yashiro, H.</dc:creator>
<dc:creator>Scholpp, S.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:creator>Hockemeyer, D.</dc:creator>
<dc:creator>Drubin, D. G.</dc:creator>
<dc:creator>Martin, B. L.</dc:creator>
<dc:creator>Matus, D. Q.</dc:creator>
<dc:creator>Koyama, M.</dc:creator>
<dc:creator>Megason, S. G.</dc:creator>
<dc:creator>Kirchhausen, T.</dc:creator>
<dc:creator>Betzig, E.</dc:creator>
<dc:date>2018-01-08</dc:date>
<dc:identifier>doi:10.1101/243352</dc:identifier>
<dc:title><![CDATA[Observing the Cell in Its Native State: Imaging Subcellular Dynamics in Multicellular Organisms]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-01-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/245183v1?rss=1">
<title>
<![CDATA[
FAIRsharing: working with and for the community to describe and link data standards, repositories and policies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/245183v1?rss=1</link>
<description><![CDATA[
In this modern, data-driven age, governments, funders and publishers expect greater transparency and reuse of research data, as well as greater access to and preservation of the data that supports research findings. Community-developed standards, such as those for the identification1 and reporting2 of data, underpin reproducible and reusable research, aid scholarly publishing, and drive both the discovery and evolution of scientific practice. The number of these standardization efforts, driven by large organizations or at the grass root level, has been on the rise since the early 2000s. Thousands of community-developed standards are available (across all disciplines), many of which have been created and/or implemented by several thousand data repositories. Nevertheless, their uptake by the research community, however, has been slow and uneven. This is mainly because investigators lack incentives to follow and adopt standards. The situation is exacerbated if standards are not promptly implemented by databases, repositories and other research tools, or endorsed by infrastructures. Furthermore, the fragmentation of community efforts results in the development of arbitrarily different, incompatible standards. In turn, this leads to standards becoming rapidly obsolete in fast-evolving research areas.nnAs with any other digital object, standards, databases and repositories are dynamic in nature, with a  life cycle that encompasses formulation, development and maintenance; their status in this cycle may vary depending on the level of activity of the developing group or community. There is an urgent need for a service that enhances the information available on the evolving constellation of heterogeneous standards, databases and repositories, guides users in the selection of these resources, and that works with developers and maintainers of these resources to foster collaboration and promote harmonization. Such an informative and educational service is vital to reduce the knowledge gap among those involved in producing, managing, serving, curating, preserving, publishing or regulating data. A diverse set of stakeholders-representing academia, industry, funding agencies, standards organizations, infrastructure providers and scholarly publishers-- both national and domain-specific as well global and general organizations-- have come together as a community, representing the core adopters, advisory board members, and/or key collaborators of the FAIRsharing resource. Here, we introduce its mission and community network. We present an evaluation of the standards landscape, focusing on those for reporting data and metadata - the most diverse and numerous of the standards - and their implementation by databases and repositories. We report on the ongoing challenge to recommend resources, and we discuss the importance of making standards invisible to the end users. We report on the ongoing challenge to recommend resources, and we discuss the importance of making standards invisible to the end users. We present guidelines that highlight the role each stakeholder group must play to maximize the visibility and adoption of standards, databases and repositories.
]]></description>
<dc:creator>Sansone, S.-A.</dc:creator>
<dc:creator>McQuilton, P.</dc:creator>
<dc:creator>Rocca-Serra, P.</dc:creator>
<dc:creator>Gonzalez-Beltran, A.</dc:creator>
<dc:creator>Izzo, M.</dc:creator>
<dc:creator>Lister, A.</dc:creator>
<dc:creator>Thurston, M.</dc:creator>
<dc:creator>FAIRsharing Community,</dc:creator>
<dc:date>2018-01-17</dc:date>
<dc:identifier>doi:10.1101/245183</dc:identifier>
<dc:title><![CDATA[FAIRsharing: working with and for the community to describe and link data standards, repositories and policies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-01-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/246389v1?rss=1">
<title>
<![CDATA[
Direct Imaging of the circular chromosome of a live bacterium 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/246389v1?rss=1</link>
<description><![CDATA[
New assays for quantitative imaging1-6 and sequencing7-11 have yielded great progress towards understanding the organizational principles of chromosomes. Yet, even for the well-studied model bacterium Escherichia coli, many basic questions remain unresolved regarding chromosomal (sub-)structure2,11, its mechanics1,2,12 and dynamics13,14, and the link between structure and function1,15,16. Here we resolve the spatial organization of the circular chromosome of bacteria by directly imaging the chromosome in live E. coli cells with a broadened cell shape. The chromosome was observed to exhibit a torus topology with a 4.2 m toroidal length and 0.4 m bundle thickness. On average, the DNA density along the chromosome shows dense right and left arms that branch from a lower-density origin of replication, and are connected at the terminus of replication by an ultrathin flexible string of DNA. At the single-cell level, the DNA density along the torus is found to be strikingly heterogeneous, with blob-like Mbp-size domains that undergo major dynamic rearrangements, splitting and merging at a minute timescale. We show that prominent domain boundaries at the terminus and origin of replication are induced by MatP proteins, while weaker transient domain boundaries are facilitated by the global transcription regulators HU and Fis. These findings provide an architectural basis for the understanding of the spatial organization of bacterial genomes.
]]></description>
<dc:creator>Wu, F.</dc:creator>
<dc:creator>Japaridze, A.</dc:creator>
<dc:creator>Zheng, X.</dc:creator>
<dc:creator>Kerssemakers, J. W. J.</dc:creator>
<dc:creator>Dekker, C.</dc:creator>
<dc:date>2018-01-11</dc:date>
<dc:identifier>doi:10.1101/246389</dc:identifier>
<dc:title><![CDATA[Direct Imaging of the circular chromosome of a live bacterium]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-01-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/246405v1?rss=1">
<title>
<![CDATA[
Widespread and targeted gene expression by systemic AAV vectors: Production, purification, and administration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/246405v1?rss=1</link>
<description><![CDATA[
We recently developed novel AAV capsids for efficient and noninvasive gene transfer across the central and peripheral nervous systems. In this protocol, we describe how to produce and systemically administer AAV-PHP viruses to label and/or genetically manipulate cells in the mouse nervous system and organs including the heart. The procedure comprises three separate stages: AAV production, intravenous delivery, and evaluation of transgene expression. The protocol spans eight days, excluding the time required to assess gene expression, and can be readily adopted by laboratories with standard molecular and cell culture capabilities. We provide guidelines for experimental design and choosing the capsid, cargo, and viral dose appropriate for the experimental aims. The procedures outlined here are adaptable to diverse biomedical applications, from anatomical and functional mapping to gene expression, silencing, and editing.
]]></description>
<dc:creator>Challis, R. C.</dc:creator>
<dc:creator>Kumar, S. R.</dc:creator>
<dc:creator>Chan, K. Y.</dc:creator>
<dc:creator>Challis, C.</dc:creator>
<dc:creator>Jang, M. J.</dc:creator>
<dc:creator>Rajendran, P. S.</dc:creator>
<dc:creator>Tompkins, J. D.</dc:creator>
<dc:creator>Shivkumar, K.</dc:creator>
<dc:creator>Deverman, B. E.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2018-01-11</dc:date>
<dc:identifier>doi:10.1101/246405</dc:identifier>
<dc:title><![CDATA[Widespread and targeted gene expression by systemic AAV vectors: Production, purification, and administration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-01-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/246470v1?rss=1">
<title>
<![CDATA[
Harmonizing semantic annotations for computational models in biology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/246470v1?rss=1</link>
<description><![CDATA[
Life science researchers use computational models to articulate and test hypotheses about the behavior of biological systems. Semantic annotation is a critical component for enhancing the interoperability and reusability of such models as well as for the integration of the data needed for model parameterization and validation. Encoded as machine-readable links to knowledge resource terms, semantic annotations describe the computational or biological meaning of what models and data represent. These annotations help researchers find and repurpose models, accelerate model composition, and enable knowledge integration across model repositories and experimental data stores. However, realizing the potential benefits of semantic annotation requires the development of model annotation standards that adhere to a community-based annotation protocol. Without such standards, tool developers must account for a variety of annotation formats and approaches, a situation that can become prohibitively cumbersome and which can defeat the purpose of linking model elements to controlled knowledge resource terms. Currently, no consensus protocol for semantic annotation exists among the larger biological modeling community. Here, we report on the landscape of current semantic annotation practices among the COmputational Modeling in BIology NEtwork (COMBINE) community and provide a set of recommendations for building a consensus approach to semantic annotation.
]]></description>
<dc:creator>Neal, M. L.</dc:creator>
<dc:creator>König, M.</dc:creator>
<dc:creator>Nickerson, D.</dc:creator>
<dc:creator>Mısırlı, G.</dc:creator>
<dc:creator>Kalbasi, R.</dc:creator>
<dc:creator>Dräger, A.</dc:creator>
<dc:creator>Atalag, K.</dc:creator>
<dc:creator>Chelliah, V.</dc:creator>
<dc:creator>Cooling, M.</dc:creator>
<dc:creator>Cook, D. L.</dc:creator>
<dc:creator>Crook, S.</dc:creator>
<dc:creator>de Alba, M.</dc:creator>
<dc:creator>Friedman, S. H.</dc:creator>
<dc:creator>Garny, A.</dc:creator>
<dc:creator>Gennari, J. H.</dc:creator>
<dc:creator>Gleeson, P.</dc:creator>
<dc:creator>Golebiewski, M.</dc:creator>
<dc:creator>Hucka, M.</dc:creator>
<dc:creator>Juty, N.</dc:creator>
<dc:creator>Le Novere, N.</dc:creator>
<dc:creator>Myers, C.</dc:creator>
<dc:creator>Olivier, B. G.</dc:creator>
<dc:creator>Sauro, H. M.</dc:creator>
<dc:creator>Scharm, M.</dc:creator>
<dc:creator>Snoep, J. L.</dc:creator>
<dc:creator>Toure, V.</dc:creator>
<dc:creator>Wipat, A.</dc:creator>
<dc:creator>Wolkenhauer, O.</dc:creator>
<dc:creator>Waltemath, D.</dc:creator>
<dc:date>2018-01-23</dc:date>
<dc:identifier>doi:10.1101/246470</dc:identifier>
<dc:title><![CDATA[Harmonizing semantic annotations for computational models in biology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-01-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/249326v1?rss=1">
<title>
<![CDATA[
Attentional set to safety recruits the medial prefrontal cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/249326v1?rss=1</link>
<description><![CDATA[
During threat assessment, the early detection of danger is highly adaptive, yet the fast orientation towards safety is also key to survival. The present study aimed to explore how the human brain searches for safety by manipulating subjects attentional set to cues associated with shock probability. Subjects were asked to judge random dots motion (RDM) direction and could be shocked for incorrect responses (RDM task) while keeping alert in detecting the shock probability cues (cue detection task). In contrast to the safe condition, where subjects searched for cues associated with no shock probability, incorrect responses to  dangerous+ (D+) cues would increase the shock probability and correct responses to  dangerous- (D-) cues would decrease shock probability. In the RDM task, results showed that relative to the D+, the safe attentional set resulted in stronger activation in the ventral medial prefrontal cortex (vmPFC), a core region involved in flexible threat assessment and safety signalling. The vmPFC was also recruited by the D-compared to the D + attentional set. In the cue detection task, shorter response times and greater accuracy were observed for D+ compared to D- and safe cues. Correspondingly, at the neural level D+ cues induced increased activity in the frontoparietal attention network including the inferior parietal lobule and intraparietal sulcus. Overall, our findings demonstrate that attentional set for searching safety recruits the vmPFC, while detection of threat elicits activity in the frontoparietal attention network, suggesting a new role for these regions in human defensive survival circuitry.nnSignificance StatementWhile early detection of threat is highly adaptive, the fast orientation towards safety is also key to survival. However, little is known about neural mechanisms underlying attentional set to safety. Using a novel dots motion paradigm combined with fMRI, we explored how human brain prepares for safety searching by manipulating subjects attentional set to cues associated with shock probability. Relative to the dangerous attentional set associated with increasing shock probability, the safe attentional set resulted in stronger activity in the ventral medial prefrontal cortex, a core region involved in flexible threat assessment and safety signalling, suggesting a new role for this region in human defensive survival system in encoding stimuli with survival significance.
]]></description>
<dc:creator>Yao, S.</dc:creator>
<dc:creator>Qi, S.</dc:creator>
<dc:creator>Kendrick, K.</dc:creator>
<dc:creator>Mobbs, D.</dc:creator>
<dc:date>2018-01-17</dc:date>
<dc:identifier>doi:10.1101/249326</dc:identifier>
<dc:title><![CDATA[Attentional set to safety recruits the medial prefrontal cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-01-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/250118v1?rss=1">
<title>
<![CDATA[
Imaging neural activity in the ventral nerve cord of behaving adult Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/250118v1?rss=1</link>
<description><![CDATA[
To understand neural circuits that control limbs, one must measure their activity during behavior. Until now this goal has been challenging, because the portion of the nervous system that contains limb premotor and motor circuits is largely inaccessible to large-scale recording techniques in intact, moving animals - a constraint that is true for both vertebrate and invertebrate models. Here, we introduce a method for 2-photon functional imaging from the ventral nerve cord of behaving adult Drosophila melanogaster. We use this method to reveal patterns of activity across nerve cord populations during grooming and walking and to uncover the functional encoding of moonwalker ascending neurons (MANs), moonwalker descending neurons (MDNs), and a novel class of locomotion-associated descending neurons. This new approach enables the direct investigation of circuits associated with complex limb movements.
]]></description>
<dc:creator>Chen, C.-L.</dc:creator>
<dc:creator>Hermans, L.</dc:creator>
<dc:creator>Viswanathan, M. C.</dc:creator>
<dc:creator>Fortun, D.</dc:creator>
<dc:creator>Unser, M.</dc:creator>
<dc:creator>Cammarato, A.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:creator>Ramdya, P.</dc:creator>
<dc:date>2018-01-22</dc:date>
<dc:identifier>doi:10.1101/250118</dc:identifier>
<dc:title><![CDATA[Imaging neural activity in the ventral nerve cord of behaving adult Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-01-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/257865v1?rss=1">
<title>
<![CDATA[
A distributed brain network predicts general intelligence from resting-state human neuroimaging data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/257865v1?rss=1</link>
<description><![CDATA[
Individual people differ in their ability to reason, solve problems, think abstractly, plan and learn. A reliable measure of this general ability, also known as intelligence, can be derived from scores across a diverse set of cognitive tasks. There is great interest in understanding the neural underpinnings of individual differences in intelligence, since it is the single best predictor of longterm life success. The most replicated neural correlate of human intelligence to date is total brain volume; however, this coarse morphometric correlate says little about function. Here we ask whether measurements of the activity of the resting brain (resting-state fMRI) might also carry information about intelligence. We used the final release of the Young Adult Human Connectome Project (N=884 subjects after exclusions), providing a full hour of resting-state fMRI per subject; controlled for gender, age, and brain volume; and derived a reliable estimate of general intelligence from scores on multiple cognitive tasks. Using a cross-validated predictive framework, we predicted 20% of the variance in general intelligence in the sampled population from their resting-state connectivity matrices. Interestingly, no single anatomical structure or network was responsible or necessary for this prediction, which instead relied on redundant information distributed across the brain.
]]></description>
<dc:creator>Dubois, J. C.</dc:creator>
<dc:creator>Galdi, P.</dc:creator>
<dc:creator>Paul, L. K.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:date>2018-01-31</dc:date>
<dc:identifier>doi:10.1101/257865</dc:identifier>
<dc:title><![CDATA[A distributed brain network predicts general intelligence from resting-state human neuroimaging data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-01-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/258566v1?rss=1">
<title>
<![CDATA[
Identification of transcriptional signatures for cell types from single-cell RNA-Seq 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/258566v1?rss=1</link>
<description><![CDATA[
Single-cell RNA-Seq makes it possible to characterize the transcriptomes of cell types and identify their transcriptional signatures via differential analysis. We present a fast and accurate method for discriminating cell types that takes advantage of the large numbers of cells that are assayed. When applied to transcript compatibility counts obtained via pseudoalignment, our approach provides a quantification-free analysis of 3 single-cell RNA-Seq that can identify previously undetectable marker genes.
]]></description>
<dc:creator>Ntranos, V.</dc:creator>
<dc:creator>Yi, L.</dc:creator>
<dc:creator>Melsted, P.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2018-02-01</dc:date>
<dc:identifier>doi:10.1101/258566</dc:identifier>
<dc:title><![CDATA[Identification of transcriptional signatures for cell types from single-cell RNA-Seq]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-02-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/260232v1?rss=1">
<title>
<![CDATA[
Development of photoactivatable drugs enables nicotinic optopharmacology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/260232v1?rss=1</link>
<description><![CDATA[
Photoactivatable ( caged) pharmacological agents have revolutionized neuroscience but the palette of available ligands is limited. We describe a general method for caging tertiary amines using an unconventional quaternary ammonium linkage that is chemically stable and elicits a desirable red-shift in activation wavelength. A photoactivatable nicotine (PA-Nic) prepared using this strategy could be uncaged via 1- or 2-photon excitation, making it useful for optopharmacology experiments to study nicotinic acetylcholine receptors (nAChRs) in different experimental preparations and spatiotemporal scales.
]]></description>
<dc:creator>Banala, S.</dc:creator>
<dc:creator>Arvin, M. C.</dc:creator>
<dc:creator>Bannon, N. M.</dc:creator>
<dc:creator>Jin, X.-T.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Zhao, G.</dc:creator>
<dc:creator>Marshall, J. J.</dc:creator>
<dc:creator>Gee, K. R.</dc:creator>
<dc:creator>Wokosin, D. L.</dc:creator>
<dc:creator>Contractor, A.</dc:creator>
<dc:creator>Henry, L. A.</dc:creator>
<dc:creator>Kozorovitskiy, Y.</dc:creator>
<dc:creator>Drenan, R. M.</dc:creator>
<dc:creator>Lavis, L. D.</dc:creator>
<dc:date>2018-02-05</dc:date>
<dc:identifier>doi:10.1101/260232</dc:identifier>
<dc:title><![CDATA[Development of photoactivatable drugs enables nicotinic optopharmacology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-02-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/260851v1?rss=1">
<title>
<![CDATA[
Single day construction of multi-gene circuits with 3G assembly 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/260851v1?rss=1</link>
<description><![CDATA[
The ability to rapidly design, build, and test prototypes is of key importance to every engineering discipline. DNA assembly often serves as a rate limiting step of the prototyping cycle for synthetic biology. Recently developed DNA assembly methods such as isothermal assembly and type IIS restriction enzyme systems take different approaches to accelerate DNA construction. We introduce a hybrid method, Golden Gate-Gibson (3G), that takes advantage of modular part libraries introduced by type IIS restriction enzyme systems and isothermal assembly s ability to build large DNA constructs in single pot reactions. Our method is highly efficient and rapid, facilitating construction of entire multi-gene circuits in a single day. Additionally, 3G allows generation of variant libraries enabling efficient screening of different possible circuit constructions. We characterize the efficiency and accuracy of 3G assembly for various construct sizes, and demonstrate 3G by characterizing variants of an inducible cell-lysis circuit.
]]></description>
<dc:creator>Halleran, A. D.</dc:creator>
<dc:creator>Swaminathan, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2018-02-10</dc:date>
<dc:identifier>doi:10.1101/260851</dc:identifier>
<dc:title><![CDATA[Single day construction of multi-gene circuits with 3G assembly]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-02-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/261115v1?rss=1">
<title>
<![CDATA[
A conserved regulatory program drives emergence of the lateral plate mesoderm 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/261115v1?rss=1</link>
<description><![CDATA[
Cardiovascular lineages develop together with kidney, smooth muscle, and limb connective tissue progenitors from the lateral plate mesoderm (LPM). How the LPM initially emerges and how its downstream fates are molecularly interconnected remain unknown. Here, we isolated a pan-LPM enhancer in the zebrafish draculin (drl) gene that provides specific LPM reporter activity from early gastrulation. In toto live imaging and lineage tracing of drl-based reporters captured the dynamic LPM emergence as lineage-restricted mesendoderm field. The drl pan-LPM enhancer responds to the transcription factors EomesoderminA, FoxH1, and MixL1 that combined with Smad activity drive LPM emergence. We uncovered specific drl reporter activity in LPM-corresponding territories of several chordates including chicken, axolotl, lamprey, Ciona, and amphioxus, revealing a universal upstream LPM program. Altogether, our work provides a mechanistic framework for LPM emergence as defined progenitor field, possibly representing an ancient mesodermal cell state that predates the primordial vertebrate embryo.
]]></description>
<dc:creator>Hess, C.</dc:creator>
<dc:creator>Prummel, K. D.</dc:creator>
<dc:creator>Nieuwenhuize, S.</dc:creator>
<dc:creator>Parker, H.</dc:creator>
<dc:creator>Rogers, K. W.</dc:creator>
<dc:creator>Kozmikova, I.</dc:creator>
<dc:creator>Racioppi, C.</dc:creator>
<dc:creator>Burger, S.</dc:creator>
<dc:creator>Brombacher, E. C.</dc:creator>
<dc:creator>Burger, A.</dc:creator>
<dc:creator>Felker, A.</dc:creator>
<dc:creator>Chiavacci, E.</dc:creator>
<dc:creator>Shah, G.</dc:creator>
<dc:creator>Huisken, J.</dc:creator>
<dc:creator>Kozmik, Z.</dc:creator>
<dc:creator>Christiaen, L.</dc:creator>
<dc:creator>Mueller, P.</dc:creator>
<dc:creator>Bronner, M.</dc:creator>
<dc:creator>Krumlauf, R.</dc:creator>
<dc:creator>Mosimann, C.</dc:creator>
<dc:date>2018-02-07</dc:date>
<dc:identifier>doi:10.1101/261115</dc:identifier>
<dc:title><![CDATA[A conserved regulatory program drives emergence of the lateral plate mesoderm]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-02-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/264465v1?rss=1">
<title>
<![CDATA[
Representation of multiple objects in macaque category-selective areas 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/264465v1?rss=1</link>
<description><![CDATA[
Object recognition in the natural world usually occurs in the presence of multiple surrounding objects, but responses of neurons in inferotemporal (IT) cortex, the large brain area responsible for object recognition, have mostly been studied only to isolated objects. We study rules governing responses to multiple objects by cells in two category-selective regions of macaque IT cortex, the middle lateral face patch (ML) and the middle body patch (MB). We find that responses of single ML and MB cells to pairs of objects could be explained by the widely-accepted framework of normalization, with one added ingredient: homogeneous category selectivity of neighboring neurons forming the normalization pool. This rule leads to winner-take-all, contralateral-take-all, or weighted averaging behavior in single cells, depending on the category, spatial configuration, and relative contrast of the two objects. The winner-take-all behavior suggests a potential mechanism for clutter-invariant representation of face and bodies under certain conditions.
]]></description>
<dc:creator>Bao, P.</dc:creator>
<dc:creator>Tsao, D. Y.</dc:creator>
<dc:date>2018-02-13</dc:date>
<dc:identifier>doi:10.1101/264465</dc:identifier>
<dc:title><![CDATA[Representation of multiple objects in macaque category-selective areas]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-02-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/272211v1?rss=1">
<title>
<![CDATA[
ProtaBank: A repository for protein design and engineering data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/272211v1?rss=1</link>
<description><![CDATA[
We present ProtaBank, a repository for storing, querying, analyzing, and sharing protein design and engineering data in an actively maintained and updated database. ProtaBank provides a format to describe and compare all types of protein mutational data, spanning a wide range of properties and techniques. It features a user-friendly web interface and programming layer that streamlines data deposition and allows for batch input and queries. The database schema design incorporates a standard format for reporting protein sequences and experimental data that facilitates comparison of results across different data sets. A suite of analysis and visualization tools are provided to facilitate discovery, to guide future designs, and to benchmark and train new predictive tools and algorithms. ProtaBank will provide a valuable resource to the protein engineering community by storing and safeguarding newly generated data, allowing for fast searching and identification of relevant data from the existing literature, and exploring correlations between disparate data sets. ProtaBank invites researchers to contribute data to the database to make it accessible for search and analysis. ProtaBank is available at https://protabank.org.nnImpactThe ProtaBank database provides a central repository for researchers to store, query, analyze, and share all types of protein engineering data. This modern database will serve a pivotal role in organizing protein engineering data and leveraging the increasingly large amounts of mutational data being generated. Together with the analysis tools, it will help scientists gain insights into sequence-function relationships, support the development of new predictive tools and algorithms, and facilitate future protein engineering efforts.nnAbbreviations
]]></description>
<dc:creator>Wang, C. Y.</dc:creator>
<dc:creator>Chang, P. M.</dc:creator>
<dc:creator>Ary, M. L.</dc:creator>
<dc:creator>Allen, B. D.</dc:creator>
<dc:creator>Chica, R. A.</dc:creator>
<dc:creator>Mayo, S. L.</dc:creator>
<dc:creator>Olafson, B. D.</dc:creator>
<dc:date>2018-02-26</dc:date>
<dc:identifier>doi:10.1101/272211</dc:identifier>
<dc:title><![CDATA[ProtaBank: A repository for protein design and engineering data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-02-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/275156v1?rss=1">
<title>
<![CDATA[
Decomposing spatially dependent and cell type specific contributions to cellular heterogeneity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/275156v1?rss=1</link>
<description><![CDATA[
Both the intrinsic regulatory network and spatial environment are contributors of cellular identity and result in cell state variations. However, their individual contributions remain poorly understood. Here we present a systematic approach to integrate both sequencing-and imaging-based single-cell transcriptomic profiles, thereby combining whole-transcriptomic and spatial information from these assays. We applied this approach to dissect the cell-type and spatial domain associated heterogeneity within the mouse visual cortex region. Our analysis identified distinct spatially associated signatures within glutamatergic and astrocyte cell compartments, indicating strong interactions between cells and their spatial environment. Using these signatures as a guide to analyze single cell RNAseq data, we identified previously unknown, but spatially associated subpopulations. As such, our integrated approach provides a powerful tool for dissecting the roles of intrinsic regulatory networks and spatial environment in the maintenance of cellular states.
]]></description>
<dc:creator>Zhu, Q.</dc:creator>
<dc:creator>Shah, S.</dc:creator>
<dc:creator>Dries, R.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:creator>Yuan, G.-C.</dc:creator>
<dc:date>2018-03-02</dc:date>
<dc:identifier>doi:10.1101/275156</dc:identifier>
<dc:title><![CDATA[Decomposing spatially dependent and cell type specific contributions to cellular heterogeneity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/275875v1?rss=1">
<title>
<![CDATA[
A genome-wide assessment of the ancestral neural crest gene regulatory network 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/275875v1?rss=1</link>
<description><![CDATA[
The neural crest is an embryonic cell population that contributes to key vertebrate-specific features including the craniofacial skeleton and peripheral nervous system. Here we examine the transcriptional profiles and chromatin accessibility of neural crest cells in the basal sea lamprey, in order to gain insight into the ancestral state of the neural crest gene regulatory network (GRN) at the dawn of vertebrates. Transcriptome analyses reveal clusters of co-regulated genes during neural crest specification and migration that show high conservation across vertebrates for dynamic programmes like Wnt modulation during the epithelial to mesenchymal transition, but also reveal novel transcription factors and cell-adhesion molecules not previously implicated in neural crest migration. ATAC-seq analysis refines the location of known cis-regulatory elements at the Hox-2 locus and uncovers novel cis-regulatory elements for Tfap2B and SoxE1. Moreover, cross-species deployment of lamprey elements in zebrafish reveals that the lamprey SoxE1 enhancer activity is deeply conserved, mediating homologous expression in jawed vertebrates. Together, our data provide new insight into the core elements of the GRN that are conserved to the base of the vertebrates, as well as expose elements that are unique to lampreys.
]]></description>
<dc:creator>Hockman, D.</dc:creator>
<dc:creator>Chong-Morrison, V.</dc:creator>
<dc:creator>Gavriouchkina, D.</dc:creator>
<dc:creator>Green, S.</dc:creator>
<dc:creator>Amemiya, C.</dc:creator>
<dc:creator>Smith, J. J.</dc:creator>
<dc:creator>Bronner, M.</dc:creator>
<dc:creator>Sauka-Spengler, T.</dc:creator>
<dc:date>2018-03-12</dc:date>
<dc:identifier>doi:10.1101/275875</dc:identifier>
<dc:title><![CDATA[A genome-wide assessment of the ancestral neural crest gene regulatory network]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/275941v1?rss=1">
<title>
<![CDATA[
Bacterial swarming reduces Proteus mirabilis and Vibrio parahaemolyticus cell stiffness and increases β-lactam susceptibility 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/275941v1?rss=1</link>
<description><![CDATA[
Swarmer cells of the gram-negative pathogenic bacteria Proteus mirabilis and Vibrio parahaemolyticus become long (>10-100 m) and multinucleate during their growth and motility on polymer surfaces. We demonstrate increasing cell length is accompanied by a large increase in flexibility. Using a microfluidic assay to measure single-cell mechanics, we identified large differences in swarmer cell stiffness of (bending rigidity of P. mirabilis, 9.6 x 10-22 N m2; V. parahaemolyticus, 9.7 x 10-23 N m2) compared to vegetative cells (1.4 x 10-20 N m2 and 3.2 x 10-22 N m2, respectively). The reduction in bending rigidity (~3-15 fold) was accompanied by a decrease in the average polysaccharide strand length of the peptidoglycan layer of the cell wall from 28-30 to 19-22 disaccharides. Atomic force microscopy revealed a reduction in P. mirabilis peptidoglycan thickness from 1.5 nm (vegetative) to 1.0 nm (swarmer) and electron cryotomography indicated changes in swarmer cell wall morphology. P. mirabilis and V. parahaemolyticus swarmer cells became increasingly sensitive to osmotic pressure and susceptible to cell wall-modifying antibiotics (compared to vegetative cells)--they were ~30% more likely to die after 3 h of treatment with minimum inhibitory concentrations of the {beta}-lactams cephalexin and penicillin G. The adaptive cost of swarming is offset by the increase in cell susceptibility to physical and chemical changes in their environment, thereby suggesting the development of new chemotherapies for bacteria that leverage swarming for colonization of hosts and survival.

ImportanceProteus mirabilis and Vibrio parahaemolyticus are bacteria that infect humans. To adapt to environmental changes, these bacteria alter their cell morphology and move collectively to access new sources of nutrients in a process referred to as  swarming. We found that a change in the composition and thickness of the peptidoglycan layer of the cell wall makes swarmer cells of P. mirabilis and V. parahaemolyticus more flexible (i.e., reduced cell stiffness) and increases their sensitivity to osmotic pressure and cell-wall targeting antibiotics (e.g., {beta}-lactams). These results highlight the importance of assessing the extracellular environment in determining antibiotic doses and the use of {beta}-lactams antibiotics for treating infections caused by swarmer cells of P. mirabilis and V. parahaemolyticus.
]]></description>
<dc:creator>Auer, G. K.</dc:creator>
<dc:creator>Oliver, P. M.</dc:creator>
<dc:creator>Rajendram, M.</dc:creator>
<dc:creator>Yao, Q.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Weibel, D. B.</dc:creator>
<dc:date>2018-03-03</dc:date>
<dc:identifier>doi:10.1101/275941</dc:identifier>
<dc:title><![CDATA[Bacterial swarming reduces Proteus mirabilis and Vibrio parahaemolyticus cell stiffness and increases β-lactam susceptibility]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/283937v1?rss=1">
<title>
<![CDATA[
Bacillus safensis FO-36b and Bacillus pumilus SAFR-032: A Whole Genome Comparison of Two Spacecraft Assembly Facility Isolates 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/283937v1?rss=1</link>
<description><![CDATA[
BackgroundBacillus strains producing highly resistant spores have been isolated from cleanrooms and space craft assembly facilities. Organisms that can survive such conditions merit planetary protection concern and if that resistance can be transferred to other organisms, a health concern too. To further efforts to understand these resistances, the complete genome of Bacillus safensis strain FO-36b, which produces spore resistant to peroxide and radiation was determined. The genome was compared to the complete genome of B. pumilus SAFR-032, as well as draft genomes of B. safensis JPL-MERTA-8-2 and the type strain B. pumilus ATCC7061T. In addition, comparisons were made to 61 draft genomes that have been mostly identified as strains of B. pumilus or B. safensis.nnResultsThe FO-36b gene order is essentially the same as that in SAFR-032 and other B. pumilus strains [1]. The annotated genome has 3850 open reading frames and 40 noncoding RNAs and riboswitches. Of these, 307 are not shared by SAFR-032, and 65 are also not shared by either MERTA or ATCC7061T. The FO-36b genome was found to have ten unique reading frames and two phage-like regions, which have homology with the Bacillus bacteriophage SPP1 (NC_004166) and Brevibacillus phage Jimmer1 (NC_029104). Differing remnants of the Jimmer1 phage are found in essentially all safensis/pumilus strains. Seven unique genes are part of these phage elements. Comparison of gyrA sequences from FO-36b, SAFR-032, ATCC7061T, and 61 other draft genomes separate the various strains into three distinct clusters. Two of these are subgroups of B. pumilus while the other houses all the B. safensis strains.nnConclusionsIt is not immediately obvious that the presence or absence of any specific gene or combination of genes is responsible for the variations in resistance seen. It is quite possible that distinctions in gene regulation can change the level of expression of key proteins thereby changing the organisms resistance properties without gain or loss of a particular gene. What is clear is that phage elements contribute significantly to genome variability. The larger comparison of multiple strains indicates that many strains named as B. pumilus actually belong to the B. safensis group.
]]></description>
<dc:creator>Tirumalai, M.</dc:creator>
<dc:creator>Stepanov, V. G.</dc:creator>
<dc:creator>Wunsche, A.</dc:creator>
<dc:creator>Montazari, S.</dc:creator>
<dc:creator>Gonzalez, R. O.</dc:creator>
<dc:creator>Venkateswaran, K.</dc:creator>
<dc:creator>Fox, G. E.</dc:creator>
<dc:date>2018-03-16</dc:date>
<dc:identifier>doi:10.1101/283937</dc:identifier>
<dc:title><![CDATA[Bacillus safensis FO-36b and Bacillus pumilus SAFR-032: A Whole Genome Comparison of Two Spacecraft Assembly Facility Isolates]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/284216v1?rss=1">
<title>
<![CDATA[
A re-examination of responding on ratio and regulated-probability interval schedules 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/284216v1?rss=1</link>
<description><![CDATA[
The higher response rates observed on ratio than on matched interval reward schedules has been attributed to the differential reinforcement of longer inter-response times (IRTs) on the interval contingency. Some data, however, seem to contradict this hypothesis, showing that the difference is still observed when the role of IRT reinforcement is neutralized by using a regulated-probability interval schedule (RPI). Given the mixed evidence for these predictions, we re-examined this hypothesis by training three groups of rats to lever press under ratio, interval and RPI schedules across two phases while matching reward rates within triads. At the end of the first phase, the master ratio and RPI groups responded at similar rates. In the second phase, an interval group yoked to the same master ratio group of the first phase responded at a lower rate than the RPI group. Post-hoc analysis showed comparable reward rates for master and yoked schedules. The experienced response-outcome rate correlations were likewise similar, and approached zero as training progressed. We discuss these results in terms of dual-system theories of instrumental conditioning.
]]></description>
<dc:creator>Perez, O. D.</dc:creator>
<dc:creator>Milton, A. L.</dc:creator>
<dc:creator>Aitken, M. R. F.</dc:creator>
<dc:creator>Dickinson, A.</dc:creator>
<dc:date>2018-03-18</dc:date>
<dc:identifier>doi:10.1101/284216</dc:identifier>
<dc:title><![CDATA[A re-examination of responding on ratio and regulated-probability interval schedules]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/285213v1?rss=1">
<title>
<![CDATA[
Third-generation in situ hybridization chain reaction: multiplexed, quantitative, sensitive, versatile, robust 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/285213v1?rss=1</link>
<description><![CDATA[
In situ hybridization based on the mechanism of hybridization chain reaction (HCR) has addressed multi-decade challenges to imaging mRNA expression in diverse organisms, offering a unique combination of multiplexing, quantitation, sensitivity, resolution, and versatility. Here, with third-generation in situ HCR, we augment these capabilities using probes and amplifiers that combine to provide automatic background suppression throughout the protocol, ensuring that even if reagents bind non-specifically within the sample they will not generate amplified background. Automatic background suppression dramatically enhances performance and robustness, combining the benefits of higher signal-to-background with the convenience of using unoptimized probe sets for new targets and organisms. In situ HCR v3.0 enables multiplexed quantitative mRNA imaging with subcellular resolution in the anatomical context of whole-mount vertebrate embryos, multiplexed quantitative mRNA flow cytometry for high-throughput single-cell expression profiling, and multiplexed quantitative single-molecule mRNA imaging in thick autofluorescent samples.nnSUMMARYIn situ hybridization chain reaction (HCR) v3.0 exploits automatic background suppression to enable multiplexed quantitative mRNA imaging and flow cytometry with dramatically enhanced ease-of-use and performance.
]]></description>
<dc:creator>Choi, H. M. T.</dc:creator>
<dc:creator>Schwarzkopf, M.</dc:creator>
<dc:creator>Fornace, M. E.</dc:creator>
<dc:creator>Acharya, A.</dc:creator>
<dc:creator>Artavanis, G.</dc:creator>
<dc:creator>Stegmaier, J.</dc:creator>
<dc:creator>Cunha, A.</dc:creator>
<dc:creator>Pierce, N. A.</dc:creator>
<dc:date>2018-03-19</dc:date>
<dc:identifier>doi:10.1101/285213</dc:identifier>
<dc:title><![CDATA[Third-generation in situ hybridization chain reaction: multiplexed, quantitative, sensitive, versatile, robust]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/288142v1?rss=1">
<title>
<![CDATA[
Role of communication network topology in controlling microbial population in consortia 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/288142v1?rss=1</link>
<description><![CDATA[
Engineering microbial consortia is an important new frontier for synthetic biology given its efficiency in performing complex tasks and endurance to environmental uncertainty. Most synthetic circuits regulate populational behaviors via cell-to-cell communications, which are affected by spatially heterogenous environments. Therefore, it is important to understand the limits on controlling system dynamics that are determined by interconnections among cell agents and provide a control strategy for engineering consortia. Here, we build a network model for a fractional population control circuit in two-strain consortia, and characterize the cell-to-cell communication network by topological properties, such as symmetry, locality and connectivity. Using linear network control theory, we relate the network topology to system outputs tracking performance. We analytically and numerically demonstrate that the minimum network control energy for accurate tracking depends on locality difference between two cell populations spatial distributions and how strongly the controller node contributes to communication strength. To realize a robust consortia, we can manipulate the communication network topology and construct strongly connected consortia by altering chemicals in environments. Our results ground the expected cell population dynamics in its spatially organized communication network, and inspire directions in cooperative control in microbial consortia.
]]></description>
<dc:creator>Ren, X.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2018-03-24</dc:date>
<dc:identifier>doi:10.1101/288142</dc:identifier>
<dc:title><![CDATA[Role of communication network topology in controlling microbial population in consortia]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/299057v1?rss=1">
<title>
<![CDATA[
Robust Perfect Adaptation in Biomolecular Reaction Networks 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/299057v1?rss=1</link>
<description><![CDATA[
For control in biomolecular systems, the most basic objective of maintaining a small error in a target variable, say the expression level of some protein, is often difficult due to the presence of both large uncertainty of every type and intrinsic limitations on the controllers implementation. This paper explores the limits of biochemically plausible controller design for the problem of robust perfect adaptation (RPA), biologists term for robust steady state tracking. It is well-known that for a large class of nonlinear systems, a system has RPA iff it has integral feedback control (IFC), which has been used extensively in real control systems to achieve RPA. However, we show that due to intrinsic physical limitations on the dynamics of chemical reaction networks (CRNs), cells cannot implement IFC directly in the concentration of a chemical species. This contrasts with electronic implementations, particularly digital, where it is trivial to implement IFC directly in a single state. Therefore, biomolecular systems have to achieve RPA by encoding the integral control variable into the network architecture of a CRN. We describe a general framework to implement RPA in CRNs and show that well-known network motifs that achieve RPA, such as (negative) integral feedback (IFB) and incoherent feedforward (IFF), are examples of such implementations. We also develop methods to solve the problem of designing integral feedback variables for unknown plants. This standard control notion is surprisingly nontrivial and relatively unstudied in biomolecular control. The methods developed here connect different existing fields and approaches on the problem of biomolecular control, and hold promise for systematic chemical reaction controller synthesis as well as analysis.
]]></description>
<dc:creator>Xiao, F.</dc:creator>
<dc:creator>Doyle, J. C.</dc:creator>
<dc:date>2018-04-11</dc:date>
<dc:identifier>doi:10.1101/299057</dc:identifier>
<dc:title><![CDATA[Robust Perfect Adaptation in Biomolecular Reaction Networks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-04-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/310698v1?rss=1">
<title>
<![CDATA[
Forces on nascent polypeptides during membrane insertion and translocation via the Sec translocon 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/310698v1?rss=1</link>
<description><![CDATA[
During ribosomal translation, nascent polypeptide chains (NCs) undergo a variety of physical processes that determine their fate in the cell. Translation arrest peptide (AP) experiments are used to measure the external pulling forces that are exerted on the NC at different lengths during translation. To elucidate the molecular origins of these forces, a recently developed coarsegrained molecular dynamics (CGMD) is used to directly simulate the observed pulling-force profiles, thereby disentangling contributions from NC-translocon and NC-ribosome interactions, membrane partitioning, and electrostatic coupling to the membrane potential. This combination of experiment and theory reveals mechanistic features of Sec-facilitated membrane integration and protein translocation, including the interplay between transient interactions and conformational changes that occur during ribosomal translation to govern protein biogenesis.
]]></description>
<dc:creator>Niesen, M.</dc:creator>
<dc:creator>Muller-Lucks, A.</dc:creator>
<dc:creator>Hedman, R.</dc:creator>
<dc:creator>von Heijne, G.</dc:creator>
<dc:creator>Miller, T. F.</dc:creator>
<dc:date>2018-04-29</dc:date>
<dc:identifier>doi:10.1101/310698</dc:identifier>
<dc:title><![CDATA[Forces on nascent polypeptides during membrane insertion and translocation via the Sec translocon]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-04-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/312009v1?rss=1">
<title>
<![CDATA[
Molecular architecture of the Legionella Dot/Icm type IV secretion system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/312009v1?rss=1</link>
<description><![CDATA[
Legionella pneumophila survives and replicates inside host cells by secreting ~300 effectors through the Dot/Icm type IVB secretion system (T4BSS). Understanding this machines structure is challenging because of its large number of components (27) and integration into all layers of the cell envelope. Previously we overcame this obstacle by imaging the Dot/Icm T4BSS in its native state within intact cells through electron cryotomography. Here we extend our observations by imaging a stabilized mutant that yielded a higher resolution map. We describe for the first time the presence of a well-ordered central channel that opens up into a windowed large (~32 nm wide) secretion chamber with an unusual 13-fold symmetry. We then dissect the complex by matching proteins to densities for many components, including all those with periplasmic domains. The placement of known and predicted structures of individual proteins into the map reveals the architecture of the T4BSS and provides a roadmap for further investigation of this amazing specialized secretion system.
]]></description>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Chang, Y.-W.</dc:creator>
<dc:creator>Jeong, K. C.</dc:creator>
<dc:creator>Vogel, J. P.</dc:creator>
<dc:creator>Jensen, G.</dc:creator>
<dc:date>2018-05-01</dc:date>
<dc:identifier>doi:10.1101/312009</dc:identifier>
<dc:title><![CDATA[Molecular architecture of the Legionella Dot/Icm type IV secretion system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/312579v1?rss=1">
<title>
<![CDATA[
Structural survey of HIV-1-neutralizing antibodies targeting Env trimer delineates epitope categories and suggests vaccine templates 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/312579v1?rss=1</link>
<description><![CDATA[
HIV-1 broadly neutralizing antibodies are desired for their therapeutic potential and as templates for vaccine design. Such antibodies target the HIV-1-envelope (Env) trimer, which is shielded from immune recognition by extraordinary glycosylation and sequence variability. Recognition by broadly neutralizing antibodies thus provides insight into how antibody can bypass these immune-evasion mechanisms. Remarkably, antibodies neutralizing >25% of HIV-1 strains have now been identified that recognize all major exposed surfaces of the prefusion-closed Env trimer. Here we analyzed all 206 broadly neutralizing antibody-HIV-1 Env complexes in the PDB with resolution suitable to define their interaction chemistries. These segregated into 20 antibody classes based on ontogeny and recognition, and into 6 epitope categories (V1V2, glycan-V3, CD4-binding site, silent face center, fusion peptide, and subunit interface) based on recognized Env residues. We measured antibody neutralization on a 208-isolate panel and analyzed features of paratope and B cell ontogeny. The number of protruding loops, CDR H3 length, and level of somatic hypermutation for broadly HIV-1 neutralizing antibodies were significantly higher than for a comparison set of non-HIV-1 antibodies. For epitope, the number of independent sequence segments was higher (P < 0.0001), as well as the glycan component surface area (P = 0.0005). Based on B cell ontogeny, paratope, and breadth, the CD4-binding site antibody IOMA appeared to be a promising candidate for lineage-based vaccine design. In terms of epitope-based vaccine design, antibody VRC34.01 had few epitope segments, low epitope-glycan content, and high epitope-conformational variability, which may explain why VRC34.01-based design is yielding promising vaccine results.
]]></description>
<dc:creator>Chuang, G.-Y.</dc:creator>
<dc:creator>Zhou, J.</dc:creator>
<dc:creator>Rawi, R.</dc:creator>
<dc:creator>Shen, C.-H.</dc:creator>
<dc:creator>Sheng, Z.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Zhang, B.</dc:creator>
<dc:creator>Zhou, T.</dc:creator>
<dc:creator>Bailer, R. T.</dc:creator>
<dc:creator>Doria-Rose, N. A.</dc:creator>
<dc:creator>Louder, M. K.</dc:creator>
<dc:creator>McKee, K.</dc:creator>
<dc:creator>Mascola, J. R.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Shapiro, L.</dc:creator>
<dc:creator>Kwong, P. D.</dc:creator>
<dc:date>2018-05-02</dc:date>
<dc:identifier>doi:10.1101/312579</dc:identifier>
<dc:title><![CDATA[Structural survey of HIV-1-neutralizing antibodies targeting Env trimer delineates epitope categories and suggests vaccine templates]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/313171v1?rss=1">
<title>
<![CDATA[
Cis-activation in the Notch signaling pathway 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/313171v1?rss=1</link>
<description><![CDATA[
The Notch signaling pathway consists of transmembrane ligands and receptors that can interact both within the same cell (cis) and across cell boundaries (trans). Previous work has shown that cis-interactions act to inhibit productive signaling. Here, by analyzing Notch activation in single cells while controlling cell density and ligand expression level, we show that cis-ligands can in fact activate Notch receptors. This cis-activation process resembles trans-activation in its ligand level dependence, susceptibility to cis-inhibition, and sensitivity to Fringe modification. Cis-activation occurred for multiple ligand-receptor pairs, in diverse cell types, and affected survival and differentiation in neural stem cells. Finally, mathematical modeling shows how cis-activation could potentially expand the capabilities of Notch signaling, for example enabling "negative" signaling. These results establish cis-activation as a prevalent mode of signaling in the Notch pathway, and should contribute to a more complete understanding of how Notch signaling functions in developmental, physiological, and biomedical contexts.
]]></description>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:creator>Santat, L. A.</dc:creator>
<dc:creator>Nandagopal, N.</dc:creator>
<dc:date>2018-05-02</dc:date>
<dc:identifier>doi:10.1101/313171</dc:identifier>
<dc:title><![CDATA[Cis-activation in the Notch signaling pathway]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/315176v1?rss=1">
<title>
<![CDATA[
Sun navigation requires compass neurons in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/315176v1?rss=1</link>
<description><![CDATA[
To follow a straight course, animals must maintain a constant heading relative to a fixed, distant landmark, a strategy termed menotaxis. In experiments using a flight simulator, we found that Drosophila adopt arbitrary headings with respect to a simulated sun, and individuals remember their heading preference between successive flights--even over gaps lasting several hours. Imaging experiments revealed that a class of neurons within the central complex, which have been previously shown to act as an internal compass, track the azimuthal motion of a sun stimulus. When these neurons are silenced, flies no longer adopt and maintain arbitrary headings, but instead exhibit frontal phototaxis. Thus, without the compass system, flies lose the ability to execute menotaxis and revert to a simpler, reflexive behavior.nnOne sentence summarySilencing the compass neurons in the central complex of Drosophila eliminates sun navigation but leaves phototaxis intact.
]]></description>
<dc:creator>Giraldo, Y. M.</dc:creator>
<dc:creator>Leitch, K. J.</dc:creator>
<dc:creator>Ros, I. K.</dc:creator>
<dc:creator>Warren, T. L.</dc:creator>
<dc:creator>Weir, P. T.</dc:creator>
<dc:creator>Dickinson, M.</dc:creator>
<dc:date>2018-05-07</dc:date>
<dc:identifier>doi:10.1101/315176</dc:identifier>
<dc:title><![CDATA[Sun navigation requires compass neurons in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/315333v1?rss=1">
<title>
<![CDATA[
Highly Multiplexed Single-Cell RNA-seq for Defining Cell Population and Transcriptional Spaces 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/315333v1?rss=1</link>
<description><![CDATA[
We describe a universal sample multiplexing method for single-cell RNA-seq in which cells are chemically labeled with identifying DNA oligonucleotides. Analysis of a 96-plex perturbation experiment revealed changes in cell population structure and transcriptional states that cannot be discerned from bulk measurements, establishing a cost effective means to survey cell populations from large experiments and clinical samples with the depth and resolution of single-cell RNA-seq.
]]></description>
<dc:creator>Gehring, J.</dc:creator>
<dc:creator>Park, J. H.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2018-05-05</dc:date>
<dc:identifier>doi:10.1101/315333</dc:identifier>
<dc:title><![CDATA[Highly Multiplexed Single-Cell RNA-seq for Defining Cell Population and Transcriptional Spaces]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/315721v1?rss=1">
<title>
<![CDATA[
Polar targeting and assembly of the Legionella Dot/Icm type IV secretion system (T4SS) by T6SS-related components 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/315721v1?rss=1</link>
<description><![CDATA[
Legionella pneumophila, the causative agent of Legionnaires disease, survives and replicates inside amoebae and macrophages by injecting a large number of protein effectors into the host cells cytoplasm via the Dot/Icm type IVB secretion system (T4BSS). Previously, we showed that the Dot/Icm T4BSS is localized to both poles of the bacterium and that polar secretion is necessary for the proper targeting of the Legionella containing vacuole (LCV). Here we show that polar targeting of the Dot/Icm core-transmembrane subcomplex (DotC, DotD, DotF, DotG and DotH) is mediated by two Dot/Icm proteins, DotU and IcmF, which are able to localize to the poles of L. pneumophila by themselves. Interestingly, DotU and IcmF are homologs of the T6SS components TssL and TssM, which are part of the T6SS membrane complex (MC). We propose that Legionella co-opted these T6SS components to a novel function that mediates subcellular localization and assembly of this T4SS. Finally, in depth examination of the biogenesis pathway revealed that polar targeting and assembly of the Legionella T4BSS apparatus is mediated by an innovative "outside-inside" mechanism.
]]></description>
<dc:creator>Jeong, K. C.</dc:creator>
<dc:creator>Gyore, J.</dc:creator>
<dc:creator>Teng, L.</dc:creator>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Vogel, J. P.</dc:creator>
<dc:date>2018-05-07</dc:date>
<dc:identifier>doi:10.1101/315721</dc:identifier>
<dc:title><![CDATA[Polar targeting and assembly of the Legionella Dot/Icm type IV secretion system (T4SS) by T6SS-related components]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/317875v1?rss=1">
<title>
<![CDATA[
The Genetic Insulator RiboJ Increases Expression of Insulated Genes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/317875v1?rss=1</link>
<description><![CDATA[
The self-cleaving ribozyme RiboJ is an insulator commonly used in genetic circuits to prevent unexpected interactions between neighboring parts. These interactions can compromise the modularity of the circuit, impeding the implementation of predictable genetic constructs. Despite its utility as an insulator, a quantitative assessment of the effect of RiboJ on the properties of downstream genetic parts is lacking. Here, we characterized the impact of insulation with RiboJ on expression of a reporter gene driven by a promoter from a library of 24 frequently employed constitutive promoters. We show that depending on the strength of the promoters, insulation with RiboJ increased protein abundance between twofold and tenfold and increased transcript abundance by an average of twofold. This result is the first to demonstrate that genetic insulators can impact the expression of downstream genes, potentially hindering the design of predictable genetic circuits and constructs.
]]></description>
<dc:creator>Clifton, K. P.</dc:creator>
<dc:creator>Jones, E. M.</dc:creator>
<dc:creator>Paudel, S.</dc:creator>
<dc:creator>Marken, J. P.</dc:creator>
<dc:creator>Monette, C. E.</dc:creator>
<dc:creator>Halleran, A. D.</dc:creator>
<dc:creator>Epp, L.</dc:creator>
<dc:creator>Saha, M. S.</dc:creator>
<dc:date>2018-05-09</dc:date>
<dc:identifier>doi:10.1101/317875</dc:identifier>
<dc:title><![CDATA[The Genetic Insulator RiboJ Increases Expression of Insulated Genes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/318675v1?rss=1">
<title>
<![CDATA[
A stochastic epigenetic switch controls the dynamics of T-cell lineage commitment 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/318675v1?rss=1</link>
<description><![CDATA[
Cell fate decisions occur through the switch-like, irreversible activation of fate-specifying genes. These activation events are often assumed to be tightly-coupled to changes in upstream transcription factors, but could also be constrained by cis-epigenetic mechanisms at individual gene loci. Here, we studied the activation of Bcl11b, which controls T-cell fate commitment. To disentangle cis and trans effects, we generated mice where two Bcl11b copies are tagged with distinguishable fluorescent proteins. Quantitative live microscopy of progenitors from these mice revealed that Bcl11b turned on after a stochastic delay averaging multiple days, which varied not only between cells but also between Bcl11b alleles within the same cell. Genetic perturbations, together with mathematical modeling, showed that a distal enhancer controls the rate of epigenetic activation, while a parallel Notch-dependent trans-acting step stimulates expression from activated loci. These results show that developmental fate transitions can be controlled by stochastic cis-acting events on individual loci.
]]></description>
<dc:creator>Ng, K. K. N.</dc:creator>
<dc:creator>Yui, M. A.</dc:creator>
<dc:creator>Mehta, A.</dc:creator>
<dc:creator>Siu, S.</dc:creator>
<dc:creator>Irwin, B.</dc:creator>
<dc:creator>Pease, S.</dc:creator>
<dc:creator>Hirose, S.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:creator>Rothenberg, E. V.</dc:creator>
<dc:creator>Kueh, H. Y.</dc:creator>
<dc:date>2018-05-10</dc:date>
<dc:identifier>doi:10.1101/318675</dc:identifier>
<dc:title><![CDATA[A stochastic epigenetic switch controls the dynamics of T-cell lineage commitment]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/328906v1?rss=1">
<title>
<![CDATA[
Metabolic marker gene mining provides insight in global mcrA diversity and, coupled with targeted genome reconstruction, sheds light on metabolic versatility of the Methanomassiliicoccales 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/328906v1?rss=1</link>
<description><![CDATA[
Over the past years, metagenomics has revolutionized our view of microbial diversity. Moreover, extracting near-complete genomes from metagenomes has led to the discovery of known metabolic traits in unsuspected lineages. Genome-resolved metagenomics relies on assembly of the sequencing reads and subsequent binning of assembled contigs, which might be hampered by strain heterogeneity or low abundance of a target organism. Here we present a complementary approach, metagenome marker gene mining, and use it to assess the global diversity of archaeal methane metabolism through the mcrA gene. To this end, we have screened 18,465 metagenomes for the presence of reads matching a database representative of all known mcrA proteins and reconstructed gene sequences from the matching reads. We use our mcrA dataset to assess the environmental distribution of the Methanomassiliicoccales and reconstruct and analyze a draft genome belonging to the  Lake Pavin cluster, an understudied environmental clade of the Methanomassiliicoccales. Thus, we show that marker gene mining can enhance the discovery power of metagenomics, by identifying novel lineages and aiding selection of targets for in-depth analyses. Marker gene mining is less sensitive to strain heterogeneity and has a lower abundance threshold than genome-resolved metagenomics, as it only requires short contigs and there is no binning step. Additionally, it is computationally cheaper than genome resolved metagenomics, since only a small subset of reads needs to be assembled. It is therefore a suitable approach to extract knowledge from the many publicly available sequencing projects.
]]></description>
<dc:creator>Speth, D. R.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2018-05-23</dc:date>
<dc:identifier>doi:10.1101/328906</dc:identifier>
<dc:title><![CDATA[Metabolic marker gene mining provides insight in global mcrA diversity and, coupled with targeted genome reconstruction, sheds light on metabolic versatility of the Methanomassiliicoccales]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/330464v1?rss=1">
<title>
<![CDATA[
Towards measuring growth rates of pathogens during infections by D2O-labeling lipidomics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/330464v1?rss=1</link>
<description><![CDATA[
RATIONALEMicrobial growth rate is an important physiological parameter that is challenging to measure in situ, partly because microbes grow slowly in many environments. Recently, it has been demonstrated that generation times of S. aureus in cystic fibrosis (CF) infections can be determined by D2O-labeling of actively synthesized fatty acids. To improve species specificity and allow growth rate monitoring for a greater range of pathogens during the treatment of infections, it is desirable to accurately quantify trace incorporation of deuterium into phospholipids.nnMETHODSLipid extracts of D2O-treated E. coli cultures were measured on LC-ESI-MS instruments equipped with TOF and Orbitrap mass analyzers, and used for comparison with the analysis of fatty acids by isotope-ratio GC-MS. We then develop an approach to enable tracking of lipid labeling, by following the transition from stationary into exponential growth in pure cultures. Lastly, we apply D2O-labeling lipidomics to clinical samples from CF patients with chronic lung infections.nnRESULTSLipidomics facilitates deuterium quantification in lipids at levels that are useful for many labeling applications (>0.03 at% D). In the E. coli cultures, labeling dynamics of phospholipids depend largely on their acyl chains and between phospholipids we notice differences that are not obvious from absolute concentrations alone. For example, cyclopropyl-containing lipids reflect the regulation of cyclopropane fatty acid synthase, which is predominantly expressed at the beginning of stationary phase. The deuterium incorporation into a lipid that is specific for S. aureus in CF sputum, indicates an average generation time of the pathogen on the order of one cell doubling per day.nnCONCLUSIONSThis study demonstrates how trace level measurement of stable isotopes in intact lipids can be used to quantify lipid metabolism in pure cultures and provides guidelines that enable growth rate measurements in microbiome samples after incubation with a low percentage of D2O.
]]></description>
<dc:creator>Neubauer, C.</dc:creator>
<dc:creator>Sessions, A. L.</dc:creator>
<dc:creator>Booth, I. R.</dc:creator>
<dc:creator>Bowen, B. P.</dc:creator>
<dc:creator>Kopf, S. H.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:creator>Dalleska, N. F.</dc:creator>
<dc:date>2018-05-25</dc:date>
<dc:identifier>doi:10.1101/330464</dc:identifier>
<dc:title><![CDATA[Towards measuring growth rates of pathogens during infections by D2O-labeling lipidomics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/331124v1?rss=1">
<title>
<![CDATA[
Mapping DNA sequence to transcription factor binding energy in vivo 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/331124v1?rss=1</link>
<description><![CDATA[
Despite the central importance of transcriptional regulation in systems biology, it has proven difficult to determine the regulatory mechanisms of individual genes, let alone entire gene networks. It is particularly difficult to analyze a promoter sequence and identify the locations, regulatory roles, and energetic properties of binding sites for transcription factors and RNA polymerase. In this work, we present a strategy for interpreting transcriptional regulatory sequences using in vivo methods (i.e. the massively parallel reporter assay Sort-Seq) to formulate quantitative models that map a transcription factor binding sites DNA sequence to transcription factor-DNA binding energy. We use these models to predict the binding energies of transcription factor binding sites to within 1 kBT of their measured values. We further explore how such a sequence-energy mapping relates to the mechanisms of trancriptional regulation in various promoter contexts. Specifically, we show that our models can be used to design specific induction responses, analyze the effects of amino acid mutations on DNA sequence preference, and determine how regulatory context affects a transcription factors sequence specificity.
]]></description>
<dc:creator>Barnes, S. L.</dc:creator>
<dc:creator>Belliveau, N. M.</dc:creator>
<dc:creator>Ireland, W. T.</dc:creator>
<dc:creator>Kinney, J. B.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2018-05-25</dc:date>
<dc:identifier>doi:10.1101/331124</dc:identifier>
<dc:title><![CDATA[Mapping DNA sequence to transcription factor binding energy in vivo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/331710v1?rss=1">
<title>
<![CDATA[
Pioneering, chromatin remodeling, and epigenetic constraint in early T-cell gene regulation by PU.1 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/331710v1?rss=1</link>
<description><![CDATA[
PU.1 is a dominant but transient regulator in early T-cell precursors and a potent transcriptional controller of developmentally important pro-T cell genes. Before T-lineage commitment, open chromatin is frequently occupied by PU.1, and many PU.1 sites lose accessibility when PU.1 is later downregulated. Pioneering activity of PU.1 was tested in in this developmentally dynamic context, by quantitating the relationships between PU.1 occupancy and site quality and accessibility as PU.1 levels naturally declined in pro-T cell development, and by using stage-specific gain and loss of function perturbations to relate binding to effects on target genes. PU.1 could bind closed genomic sites, but rapidly opened many of them, despite the absence of its frequent collaborators, C/EBP factors. The dynamic properties of PU.1 engagements implied that PU.1 binding affinity and concentration determine its occupancy choices, but with quantitative tradeoffs for occupancy between site sequence quality and stage-dependent site accessibility in chromatin. At non-promoter sites PU.1 binding criteria were more stringent than at promoters, and PU.1 was also much more effective as a transcriptional regulator at non-promoter sites where local chromatin accessibility depended on the presence of PU.1. Runx motifs and Runx1 binding were often linked to PU.1 at open sites, but highly expressed PU.1 could bind its sites without Runx1. Notably, closed chromatin presented a qualitative barrier to occupancy by the PU.1 DNA binding domain alone. Thus, effective pioneering at closed chromatin sites also depends on requirements beyond site recognition served by non-DNA binding domains of PU.1.
]]></description>
<dc:creator>Ungerback, J.</dc:creator>
<dc:creator>Hosokawa, H.</dc:creator>
<dc:creator>Wang, X.</dc:creator>
<dc:creator>Strid, T.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>Sigvardsson, M.</dc:creator>
<dc:creator>Rothenberg, E. V.</dc:creator>
<dc:date>2018-05-25</dc:date>
<dc:identifier>doi:10.1101/331710</dc:identifier>
<dc:title><![CDATA[Pioneering, chromatin remodeling, and epigenetic constraint in early T-cell gene regulation by PU.1]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/331884v1?rss=1">
<title>
<![CDATA[
Human-induced decrease of ectomycorrhizal vegetation led to loss in global soil carbon content 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/331884v1?rss=1</link>
<description><![CDATA[
Vegetation impacts on ecosystem functioning are mediated by mycorrhiza, a plant-fungal association formed by most plant species. Ecosystems dominated by distinct mycorrhizal types differ strongly in their biogeochemistry. Quantitative analyses of mycorrhizal impacts on ecosystem functioning are hindered by the absence of information on mycorrhizal distribution. We present the first global high-resolution maps of vegetation biomass distribution among main types of mycorrhizal associations. Arbuscular, ecto-, ericoid and non-mycorrhizal vegetation store 241{+/-}15, 100{+/-}17, 7{+/-}1.8 and 29 {+/-} 5.5 GT carbon in aboveground biomass, respectively. Soil carbon stocks in both topsoil and subsoil are positively related to the biomass fraction of ectomycorrhizal plants in the community, though the strength of this relationship varies across biomes. We show that human-induced transformations of Earths ecosystems have reduced ectomycorrhizal vegetation, with potential knock-on effects on terrestrial carbon stocks. Our work provides a benchmark for spatially explicit global quantitative assessments of mycorrhizal impacts on ecosystem functioning and biogeochemical cycles.nnOne Sentence SummaryFirst maps of the global distribution of mycorrhizal plants reveal global losses of ectomycorrhizal vegetation, and quantitative links between mycorrhizal vegetation patterns and terrestrial carbon stocks.
]]></description>
<dc:creator>Soudzilovskaia, N. A.</dc:creator>
<dc:creator>van Bodegom, P. M.</dc:creator>
<dc:creator>Terrer Moreno, C.</dc:creator>
<dc:creator>van't Zelfde, M.</dc:creator>
<dc:creator>McCallum, I.</dc:creator>
<dc:creator>Fisher, J. B.</dc:creator>
<dc:creator>McCormack, L. M.</dc:creator>
<dc:creator>Brundrett, M.</dc:creator>
<dc:creator>Tedersoo, L.</dc:creator>
<dc:date>2018-05-26</dc:date>
<dc:identifier>doi:10.1101/331884</dc:identifier>
<dc:title><![CDATA[Human-induced decrease of ectomycorrhizal vegetation led to loss in global soil carbon content]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/334003v1?rss=1">
<title>
<![CDATA[
Optogenetic manipulation of medullary neurons in the locust optic lobe 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/334003v1?rss=1</link>
<description><![CDATA[
Locust is a widely used animal model for studying sensory processing and its relation to behavior. Due to the lack of genomic information, genetic tools to manipulate neural circuits in locusts are not yet available. We examined whether Semliki Forest virus is suitable to mediate exogenous gene expression in neurons of the locust optic lobe. We subcloned a channelrhodopsin variant and the yellow fluorescent protein Venus into a Semliki Forest virus vector and injected the virus into the optic lobe of locusts (Schistocerca americana). Fluorescence was observed in all injected optic lobes. Most neurons that expressed the recombinant proteins were located in the first two neuropils of the optic lobe, the lamina and medulla. Extracellular recordings demonstrated that laser illumination increased the firing rate of medullary neurons expressing channelrhodopsin. The optogenetic activation of the medullary neurons also triggered firing of a postsynaptic, looming-sensitive neuron, the Lobula Giant Movement Detector (LGMD). These results indicate that Semliki Forest virus is efficient at mediating transient exogenous gene expression and provides a tool to manipulate neural circuits in the locust nervous system and likely other insects.nnNew and NoteworthyUsing Semliki Forest virus, we efficiently delivered channelrhodopsin into neurons of the locust optic lobe. We demonstrate that laser illumination increases the firing of the medullary neurons expressing channelrhodopsin and of an identified postsynaptic target neuron, the LGMD neuron. This technique allows to manipulate the neuronal activity in locust neural circuits using optogenetics.
]]></description>
<dc:creator>Wang, H.</dc:creator>
<dc:creator>Dewell, R. B.</dc:creator>
<dc:creator>Ehrengruber, M. U.</dc:creator>
<dc:creator>Segev, E.</dc:creator>
<dc:creator>Reimer, J.</dc:creator>
<dc:creator>Roukes, M. L.</dc:creator>
<dc:creator>Gabbiani, F.</dc:creator>
<dc:date>2018-05-30</dc:date>
<dc:identifier>doi:10.1101/334003</dc:identifier>
<dc:title><![CDATA[Optogenetic manipulation of medullary neurons in the locust optic lobe]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/334144v1?rss=1">
<title>
<![CDATA[
The Metabolic Capability and Phylogenetic Diversity of Mono Lake During a Bloom of the Eukaryotic Phototroph Picocystis strain ML 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/334144v1?rss=1</link>
<description><![CDATA[
Algal blooms in lakes are often associated with anthropogenic eutrophication; however, they can occur naturally. In Spring of 2016 Mono Lake, a hyperalkaline lake in California, was near the height of a rare bloom of the algae Picocystis strain ML and at the apex of a multi-year long drought. These conditions presented a unique sampling opportunity to investigate microbiological dynamics during an intense natural bloom. We conducted a comprehensive molecular analysis along a depth transect near the center of the lake from surface to 25 m depth during June 2016. Across sampled depths, rRNA gene sequencing revealed that Picocystis associated chloroplast were found at 40-50 % relative abundance, greater than values recorded previously. Despite the presence of the photosynthetic oxygenic algal genus Picocystis, oxygen declined below detectible limits below 15 m depth, corresponding with an increase in microorganisms known to be anaerobic. In contrast to previously sampled years, metagenomic and metatranscriptomic data suggested a loss of sulfate reducing microorganisms throughout the lakes water column. Gene transcripts associated with Photosystem I and II were expressed at both 2 m and 25 m, suggesting that limited oxygen production may occur at extremely low light levels at depth within the lake. Oxygenic photosynthesis under low light conditions, in the absence of potential grazing by the brine shrimp Artemia, may allow for a cryptic redox cycle to occur in an otherwise anoxic setting at depth in the lake with the following effects: enhanced productivity, reduced grazing pressure on Picocystis, and an exacerbation of bloom.nnIMPORTANCEMono Lake, California provides habitat to a unique ecological community that is heavily stressed due to recent human water diversions and a period of extended drought. To date, no baseline information exists about Mono Lake to understand how the microbial community responds to drought, bloom, and what genetic functions are lost in the water column. While previously identified anaerobic members of the microbial community disappear from the water column during drought and bloom, sediment samples suggest these microorganisms seek refuge at lake bottom or in the subsurface. Thus, the sediments may represent a type of seed bank which could restore the microbial community as a bloom subsides. Our work also sheds light on the activity of the halotolerant algae Picocystis strain ML during a bloom at Mono Lake, its ability to potentially produce oxygen via photosynthesis even under extreme low-light conditions, and how the remainder of the microbial community responds.
]]></description>
<dc:creator>Stamps, B. W.</dc:creator>
<dc:creator>Nunn, H. S.</dc:creator>
<dc:creator>Petryshyn, V. A.</dc:creator>
<dc:creator>Oremland, R. S.</dc:creator>
<dc:creator>Miller, L. G.</dc:creator>
<dc:creator>Rosen, M.</dc:creator>
<dc:creator>Bauer, K. W.</dc:creator>
<dc:creator>Thompson, K. J.</dc:creator>
<dc:creator>Tookmanian, E. M.</dc:creator>
<dc:creator>Waldeck, A. R.</dc:creator>
<dc:creator>Lloyd, S. J.</dc:creator>
<dc:creator>Johnson, H. A.</dc:creator>
<dc:creator>Stevenson, B. S.</dc:creator>
<dc:creator>Berelson, W.</dc:creator>
<dc:creator>Corsetti, F. A.</dc:creator>
<dc:creator>Spear, J. R.</dc:creator>
<dc:date>2018-05-30</dc:date>
<dc:identifier>doi:10.1101/334144</dc:identifier>
<dc:title><![CDATA[The Metabolic Capability and Phylogenetic Diversity of Mono Lake During a Bloom of the Eukaryotic Phototroph Picocystis strain ML]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/335919v1?rss=1">
<title>
<![CDATA[
Binary transcriptional control of pattern formation in development 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/335919v1?rss=1</link>
<description><![CDATA[
Predicting developmental outcomes from regulatory DNA sequence and transcription factor patterns remains an open challenge in physical biology. Using stripe 2 of the even-skipped gene in Drosophila embryos as a case study, we dissect the regulatory forces underpinning a key step along the developmental decision-making cascade: the generation of cytoplasmic mRNA patterns via the control of transcription in individual cells. Using live imaging and computational approaches, we found that the transcriptional burst frequency is modulated across the stripe to control the mRNA production rate. However, we discovered that bursting alone cannot quantitatively recapitulate the formation of the stripe, and that control of the window of time over which each nucleus transcribes even-skipped plays a critical role in stripe formation. Theoretical modeling revealed that these regulatory strategies--bursting and the time window--obey different kinds of regulatory logic, suggesting that the stripe is shaped by the interplay of two distinct underlying molecular processes.
]]></description>
<dc:creator>Lammers, N. C.</dc:creator>
<dc:creator>Galstyan, V.</dc:creator>
<dc:creator>Reimer, A.</dc:creator>
<dc:creator>Medin, S. A.</dc:creator>
<dc:creator>Wiggins, C. H.</dc:creator>
<dc:creator>Garcia, H. G.</dc:creator>
<dc:date>2018-05-31</dc:date>
<dc:identifier>doi:10.1101/335919</dc:identifier>
<dc:title><![CDATA[Binary transcriptional control of pattern formation in development]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/335984v1?rss=1">
<title>
<![CDATA[
Regulation of neural stem cell fate by the transcriptional repressor Capicua 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/335984v1?rss=1</link>
<description><![CDATA[
Capicua (Cic) is a transcriptional repressor mutated in the brain cancer oligodendroglioma. Despite its cancer link, little is known of Cics function in the brain. Here, we investigated the relationship between Cic expression and cell type specification in the brain. Cic is strongly expressed in astrocytic and neuronal lineage cells but is more weakly expressed in stem cells and oligodendroglial lineage cells. Using a new conditional Cic knockout mouse, we show that forebrain-specific Cic deletion increases proliferation and self-renewal of neural stem cells. Furthermore, Cic loss biases neural stem cells toward glial lineage selection, expanding the pool of oligodendrocyte precursor cells (OPCs). These proliferation and lineage selection effects in the developing brain are dependent on de-repression of Ets transcription factors. In patient-derived oligodendroglioma cells, CIC re-expression or ETV5 blockade decreases lineage bias, proliferation, self-renewal and tumorigenicity. Our results identify Cic is an important regulator of cell fate in neurodevelopment and oligodendroglioma, and suggest that its loss contributes to oligodendroglioma by promoting proliferation and an OPC-like identity via Ets overactivity.
]]></description>
<dc:creator>Ahmad, S. T.</dc:creator>
<dc:creator>Rogers, A. D.</dc:creator>
<dc:creator>Chen, M. J.</dc:creator>
<dc:creator>Dixit, R.</dc:creator>
<dc:creator>Adnani, L.</dc:creator>
<dc:creator>Frankiw, L.</dc:creator>
<dc:creator>Lawn, S. O.</dc:creator>
<dc:creator>Blough, M. D.</dc:creator>
<dc:creator>Alshehri, M.</dc:creator>
<dc:creator>Wu, W.</dc:creator>
<dc:creator>Robbins, S. M.</dc:creator>
<dc:creator>Cairncross, G.</dc:creator>
<dc:creator>Schuurmans, C.</dc:creator>
<dc:creator>Chan, J.</dc:creator>
<dc:date>2018-05-31</dc:date>
<dc:identifier>doi:10.1101/335984</dc:identifier>
<dc:title><![CDATA[Regulation of neural stem cell fate by the transcriptional repressor Capicua]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/339234v1?rss=1">
<title>
<![CDATA[
Dynamics and spatial genomics of the nascent transcriptome in single mESCs by intron seqFISH 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/339234v1?rss=1</link>
<description><![CDATA[
Recent single cell experiments have revealed significant heterogeneities at the levels of transcription, DNA methylation and chromosome organization in individual cells. However, existing method of profiling mRNAs effectively averages transcriptional dynamics over many hours due to hours-long life time of most mRNAs. To capture the instantaneous activity of the transcriptome that reflects the rapid regulatory changes in cells, we imaged up to 10,421 nascent transcription active sites (TAS) in single mouse embryonic stem cells using seqFISH followed by multiple rounds of single molecule FISH and immunofluorescence. We observed that nascent transcription active sites appear to be distributed on the surface of individual chromosome territories and are dispersed throughout the nucleus. In addition, there are significant variability in the number of active transcription sites in single cells, representing globally more active to quiescent states. These states interconverted on the time scale of 2 hours as determined by a single cell pulse-chase experiment. Thus, transcriptome level seqFISH experiments provide an unprecedented spatial and dynamic view of chromosome organization and global nascent transcription activity in single cells.
]]></description>
<dc:creator>Shah, S.</dc:creator>
<dc:creator>Takei, Y.</dc:creator>
<dc:creator>Zhou, W.</dc:creator>
<dc:creator>Lubeck, E.</dc:creator>
<dc:creator>Yun, J.</dc:creator>
<dc:creator>Koulena, N.</dc:creator>
<dc:creator>Liaw, E. J.</dc:creator>
<dc:creator>Amin, M.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:date>2018-06-05</dc:date>
<dc:identifier>doi:10.1101/339234</dc:identifier>
<dc:title><![CDATA[Dynamics and spatial genomics of the nascent transcriptome in single mESCs by intron seqFISH]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-06-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/339259v1?rss=1">
<title>
<![CDATA[
Connecting the dots between mechanosensitive channel abundance, osmotic shock, and survival at single-cell resolution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/339259v1?rss=1</link>
<description><![CDATA[
Rapid changes in extracellular osmolarity are one of many insults microbial cells face on a daily basis. To protect against such shocks, Escherichia coli and other microbes express several types of transmembrane channels which open and close in response to changes in membrane tension. In E. coli, one of the most abundant channels is the mechanosensitive channel of large conductance (MscL). While this channel has been heavily characterized through structural methods, electrophysiology, and theoretical modeling, our understanding of its physiological role in preventing cell death by alleviating high membrane tension remains tenuous. In this work, we examine the contribution of MscL alone to cell survival after osmotic shock at single cell resolution using quantitative fluorescence microscopy. We conduct these experiments in an E. coli strain which is lacking all mechanosensitive channel genes save for MscL whose expression is tuned across three orders of magnitude through modifications of the Shine-Dalgarno sequence. While theoretical models suggest that only a few MscL channels would be needed to alleviate even large changes in osmotic pressure, we find that between 500 and 700 channels per cell are needed to convey upwards of 80% survival. This number agrees with the average MscL copy number measured in wild-type E. coli cells through proteomic studies and quantitative Western blotting. Furthermore, we observe zero survival events in cells with less than 100 channels per cell. This work opens new questions concerning the contribution of other mechanosensitive channels to survival as well as regulation of their activity.
]]></description>
<dc:creator>Chure, G. D.</dc:creator>
<dc:creator>Lee, H. J.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2018-06-05</dc:date>
<dc:identifier>doi:10.1101/339259</dc:identifier>
<dc:title><![CDATA[Connecting the dots between mechanosensitive channel abundance, osmotic shock, and survival at single-cell resolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-06-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/348037v1?rss=1">
<title>
<![CDATA[
Refining the application of microbial lipids as tracers of Staphylococcus aureus growth rates in cystic fibrosis sputum 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/348037v1?rss=1</link>
<description><![CDATA[
Chronic lung infections in cystic fibrosis (CF) could be treated more effectively if the effect of antimicrobials on pathogens in situ were known. Here, we compared changes in the microbial community composition and pathogen growth rates in longitudinal studies of CF patients undergoing intravenous antibiotic administration during pulmonary exacerbations. Microbial community composition was measured by NanoString DNA analysis and growth rates were obtained by incubating CF sputum with heavy water and tracing incorporation of deuterium into two different anteiso fatty acids (a-C15:0 and a-C17:0) using gas chromatography-mass spectrometry (GC/MS). Prior to this study, both lipids were thought to be specific for Staphylococcaceae and hence their isotopic enrichment was interpreted as a growth proxy for S. aureus. Our experiments revealed, however, that Prevotella is also a relevant microbial producer of a-C17:0 fatty acid in some CF patients, thus deuterium incorporation into these lipids is better interpreted as a more general pathogen growth rate proxy. Even accounting for a small non-microbial background source detected in some patient samples, a-C15:0 fatty acid still appear to be a relatively robust proxy for CF pathogens, revealing a median generation time of ~1.5 days, similar to prior observations. Contrary to our expectations, pathogen growth rates remained relatively stable throughout exacerbation treatment. We suggest two best practices for application of stable isotope probing in CF sputum: (1) parallel determination of microbial community composition in CF sputum using culture-independent tools, and (2) analysis of samples with a minimum a-C15:0 concentration of 0.1 weight percent of saturated fatty acids.nnIMPORTANCEIn chronic lung infections, populations of microbial pathogens change and mature in ways that are often unknown, which makes it challenging to identify appropriate treatment options. A promising tool to better understand the physiology of microorganisms in a patient is stable-isotope probing, which we previously developed to estimate the growth rates of S. aureus in cystic fibrosis (CF) sputum. Here, we tracked microbial communities in a cohort of CF patients and found that anteiso fatty acids can also originate from other sources in CF sputum. This awareness led us to develop an new workflow for the application of stable isotope probing in this context, improving our ability to estimate pathogen generation times in clinical samples.
]]></description>
<dc:creator>Neubauer, C.</dc:creator>
<dc:creator>Kasi, A. S.</dc:creator>
<dc:creator>Grahl, N.</dc:creator>
<dc:creator>Sessions, A. L.</dc:creator>
<dc:creator>Kopf, S.</dc:creator>
<dc:creator>Kato, R.</dc:creator>
<dc:creator>Hogan, D. A.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2018-06-15</dc:date>
<dc:identifier>doi:10.1101/348037</dc:identifier>
<dc:title><![CDATA[Refining the application of microbial lipids as tracers of Staphylococcus aureus growth rates in cystic fibrosis sputum]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-06-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/348052v1?rss=1">
<title>
<![CDATA[
Cell boundary confinement sets the size and position of the E. coli chromosome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/348052v1?rss=1</link>
<description><![CDATA[
While the spatiotemporal structure of the genome is crucial to its biological function, many basic questions remain unanswered on the morphology and segregation of chromosomes. Here, we experimentally show in Escherichia coli that spatial confinement plays a dominant role in determining both the chromosome size and position. In non-dividing cells with lengths up to 10 times normal, single chromosomes are observed to expand more than 4 fold in size, an effect only modestly influenced by deletions of various nucleoid-associated proteins. Chromosomes show pronounced internal dynamics but exhibit a robust positioning where single nucleoids reside strictly at mid-cell, while two nucleoids self-organize at [1/4] and [3/4] cell positions. Molecular dynamics simulations of model chromosomes recapitulate these phenomena and indicate that these observations can be attributed to depletion effects induced by cytosolic crowders. These findings highlight boundary confinement as a key causal factor that needs to be considered for understanding chromosome organization.
]]></description>
<dc:creator>Wu, F.</dc:creator>
<dc:creator>Swain, P.</dc:creator>
<dc:creator>Kuijpers, L.</dc:creator>
<dc:creator>Zheng, X.</dc:creator>
<dc:creator>Felter, K.</dc:creator>
<dc:creator>Guurink, M.</dc:creator>
<dc:creator>Chaudhuri, D.</dc:creator>
<dc:creator>Mulder, B.</dc:creator>
<dc:creator>Dekker, C.</dc:creator>
<dc:date>2018-06-15</dc:date>
<dc:identifier>doi:10.1101/348052</dc:identifier>
<dc:title><![CDATA[Cell boundary confinement sets the size and position of the E. coli chromosome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-06-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/364331v1?rss=1">
<title>
<![CDATA[
Resource limitation modulates the fate of dissimilated nitrogen in a dual-pathway Actinobacterium 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/364331v1?rss=1</link>
<description><![CDATA[
Respiratory ammonification and denitrification are two evolutionarily unrelated dissimilatory nitrogen (N) processes central to the global N cycle, the activity of which is thought to be controlled by carbon (C) to nitrate (NO3-) ratio. Here we find that Intrasporangium calvum C5, a novel menaquinone-based dual-pathway denitrifier/respiratory ammonifier, disproportionately utilizes ammonification rather than denitrification when grown under carbon or nitrate limitation, not C:NO3- ratio. Higher growth rates are promoted by ammonification and metabolite and transcriptional profiles during growth show that the bacterium produces its own formate from a fermentable carbon source (lactate) to further generate a proton motive force for the ammonification pathway. Transcript abundances encoding for nitrite reducing enzymes, NrfAH and NirK, also significantly increase in response to nitrite production. Mechanistically, our results suggest that pathway selection is driven by intracellular redox potential (redox poise), which may be lowered during resource limitation, thereby decreasing catalytic activity of upstream electron transport steps needed for denitrification enzymes. Our work advances our understanding of the biogeochemical flexibility of N-cycling organisms and pathway evolution.
]]></description>
<dc:creator>Vuono, D. C.</dc:creator>
<dc:creator>Read, R. W.</dc:creator>
<dc:creator>Hemp, J.</dc:creator>
<dc:creator>Sullivan, B. W.</dc:creator>
<dc:creator>Arnone, J. A.</dc:creator>
<dc:creator>Neveux, I.</dc:creator>
<dc:creator>Blank, B.</dc:creator>
<dc:creator>Staub, C.</dc:creator>
<dc:creator>Loney, E.</dc:creator>
<dc:creator>Miceli, D.</dc:creator>
<dc:creator>Winkler, M.</dc:creator>
<dc:creator>Chakraborty, R.</dc:creator>
<dc:creator>Stahl, D. A.</dc:creator>
<dc:creator>Grzymski, J. J.</dc:creator>
<dc:date>2018-07-08</dc:date>
<dc:identifier>doi:10.1101/364331</dc:identifier>
<dc:title><![CDATA[Resource limitation modulates the fate of dissimilated nitrogen in a dual-pathway Actinobacterium]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-07-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/364448v1?rss=1">
<title>
<![CDATA[
Expression reflects population structure 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/364448v1?rss=1</link>
<description><![CDATA[
Population structure in genotype data has been extensively studied, and is revealed by looking at the principal components of the genotype matrix. However, no similar analysis of population structure in gene expression data has been conducted, in part because a naive principal components analysis of the gene expression matrix does not cluster by population. We identify a linear projection that reveals population structure in gene expression data. Our approach relies on the coupling of the principal components of genotype to the principal components of gene expression via canonical correlation analysis. Futhermore, we analyze the variance of each gene within the projection matrix to determine which genes significantly influence the projection. We identify thousands of significant genes, and show that a number of the top genes have been implicated in diseases that disproportionately impact African Americans.nnAuthor SummaryHigh dimensional, multi-modal genomics datasets are becoming increasingly common, which warrants investigation into analysis techniques that can reveal structure in the data without over-fitting. Here, we show that the coupling of principal component analysis to canonical correlation analysis offers an efficient approach to exploratory analysis of this kind of data. We apply this method to the GEUVADIS dataset of genotype and gene expression values of European and Yoruban individuals, finding as-of-yet unstudied population structure in the gene expression values. Moreover, many of the top genes identified by our method have been previously implicated in diseases that disproportionately impact African Americans.
]]></description>
<dc:creator>Brown, B. C.</dc:creator>
<dc:creator>Bray, N. L.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2018-07-08</dc:date>
<dc:identifier>doi:10.1101/364448</dc:identifier>
<dc:title><![CDATA[Expression reflects population structure]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-07-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/366930v1?rss=1">
<title>
<![CDATA[
The expanded universe of prokaryotic Argonaute proteins 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/366930v1?rss=1</link>
<description><![CDATA[
The members of the ancient family of Argonaute (Ago) proteins are present in all domains of life. The common feature of Ago proteins is the ability to bind small nucleic acid guides and use them for sequence-specific recognition - and sometimes cleavage - of complementary targets. While eukaryotic Ago (eAgo) proteins are key players in RNA interference and related pathways, the properties and functions of these proteins in archaeal and bacterial species have just started to emerge. We undertook comprehensive exploration of prokaryotic Ago (pAgo) proteins in sequenced genomes and almost tripled the number of previously analyzed genes of this family. In comparison with eAgos, pAgos are highly diverse and have likely spread by horizontal gene transfer. Many pAgos contain divergent variants of the conserved domains involved in interactions with nucleic acids and in target cleavage, while having extra domains that are absent in eAgos, suggesting that they might have unusual specificities in the nucleic acid recognition and processing. Many pAgos, including catalytically inactive variants, are associated with putative nucleases, helicases and DNA binding proteins in the same gene or operon, suggesting that they are involved in DNA processing. The great diversity of pAgos revealed by our analysis opens new ways for exploration of their functions in host cells and their use as potential tools in genome editing.
]]></description>
<dc:creator>Ryazansky, S.</dc:creator>
<dc:creator>Kulbachinskiy, A.</dc:creator>
<dc:creator>Aravin, A.</dc:creator>
<dc:date>2018-07-10</dc:date>
<dc:identifier>doi:10.1101/366930</dc:identifier>
<dc:title><![CDATA[The expanded universe of prokaryotic Argonaute proteins]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-07-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/367714v1?rss=1">
<title>
<![CDATA[
Selective Permeability of Carboxysome Shell Pores to Anionic Molecules 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/367714v1?rss=1</link>
<description><![CDATA[
Carboxysomes are closed polyhedral cellular microcompartments that increase the efficiency of carbon fixation in autotrophic bacteria. Carboxysome shells consist of small proteins that form hexameric units with semi-permeable central pores containing binding sites for anions. This feature is thought to selectively allow access to RuBisCO enzymes inside the carboxysome by [Formula] (the dominant form of CO2 in the aqueous solution at pH 7.4) but not O2, which leads to a non-productive reaction. To test this hypothesis, here we use molecular dynamics simulations to characterize the energetics and permeability of CO2, O2, and [Formula] through the central pores of two different shell proteins, namely, CsoS1A of -carboxysome and CcmK4 of {beta}-carboxysome shells. We find that the central pores are in fact selectively permeable to anions such as [Formula], as predicted by the model.
]]></description>
<dc:creator>Mahinthichaichan, P.</dc:creator>
<dc:creator>Morris, D. M.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:creator>Tajkhorshid, E.</dc:creator>
<dc:date>2018-07-11</dc:date>
<dc:identifier>doi:10.1101/367714</dc:identifier>
<dc:title><![CDATA[Selective Permeability of Carboxysome Shell Pores to Anionic Molecules]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-07-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/369397v1?rss=1">
<title>
<![CDATA[
The structural complexity of the Gammaproteobacteria flagellar motor is related to the type of its torque-generating stators 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/369397v1?rss=1</link>
<description><![CDATA[
The bacterial flagellar motor is a cell-envelope-embedded macromolecular machine that functions as a propeller to move the cell. Rather than being an invariant machine, the flagellar motor exhibits significant variability between species, allowing bacteria to adapt to, and thrive in, a wide range of environments. For instance, different torque-generating stator modules allow motors to operate in conditions with different pH and sodium concentrations and some motors are adapted to drive motility in high-viscosity environments. How such diversity evolved is unknown. Here we use electron cryo-tomography to determine the in situ macromolecular structures of the flagellar motors of three Gammaproteobacteria species: Legionella pneumophila, Pseudomonas aeruginosa, and Shewanella oneidensis MR-1, providing the first views of intact motors with dual stator systems. Complementing our imaging with bioinformatics analysis, we find a correlation between the stator system of the motor and its structural complexity. Motors with a single H+-driven stator system have only the core P- and L-rings in their periplasm; those with dual H+-driven stator systems have an extra component elaborating their P-ring; and motors with Na+- (or dual Na+-H+)- driven stator systems have additional rings surrounding both their P- and L-rings. Our results suggest an evolution of structural complexity that may have enabled pathogenic bacteria like L. pneumophila and P. aeruginosa to colonize higher-viscosity environments in animal hosts.
]]></description>
<dc:creator>Kaplan, M.</dc:creator>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Subramanian, P.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>Kjaer, A.</dc:creator>
<dc:creator>Pirbadian, S.</dc:creator>
<dc:creator>Ortega, D. R.</dc:creator>
<dc:creator>El-Naggar, M. Y.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2018-07-14</dc:date>
<dc:identifier>doi:10.1101/369397</dc:identifier>
<dc:title><![CDATA[The structural complexity of the Gammaproteobacteria flagellar motor is related to the type of its torque-generating stators]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-07-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/369405v1?rss=1">
<title>
<![CDATA[
Stable sub-complexes observed in situ suggest a modular assembly pathway of the bacterial flagellar motor 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/369405v1?rss=1</link>
<description><![CDATA[
The self-assembly of cellular macromolecular machines such as the bacterial flagellar motor requires the spatio-temporal synchronization of gene expression, protein localization and association of a dozen or more unique components. In Salmonella and Escherichia coli, a sequential, outward assembly mechanism has been proposed for the flagellar motor starting from the inner membrane, with each subsequent component stabilizing the last. Here, using electron cryo-tomography of intact Legionella pneumophila, Pseudomonas aeruginosa and Shewanella oneidensis cells, we observe stable outer-membrane-embedded sub-complexes of the flagellar motor. These sub-complexes consist of the periplasmic embellished P- and L-rings, in the absence of other flagellar components, and bend the membrane inward dramatically. Additionally, we also observe independent inner-membrane sub-complexes consisting of the C- and MS-rings and export apparatus. These results suggest an alternate model for flagellar motor assembly in which outer- and inner-membrane-associated sub-complexes form independently and subsequently join, enabling later steps of flagellar production to proceed.
]]></description>
<dc:creator>Kaplan, M.</dc:creator>
<dc:creator>Subramanian, P.</dc:creator>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>Pirbadian, S.</dc:creator>
<dc:creator>Starwalt-Lee, R.</dc:creator>
<dc:creator>Gralnick, J. A.</dc:creator>
<dc:creator>El-Naggar, M. Y.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2018-07-14</dc:date>
<dc:identifier>doi:10.1101/369405</dc:identifier>
<dc:title><![CDATA[Stable sub-complexes observed in situ suggest a modular assembly pathway of the bacterial flagellar motor]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-07-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/376657v1?rss=1">
<title>
<![CDATA[
3D-printable tools for developmental biology: Improving embryo injection and screening techniques through 3D-printing technology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/376657v1?rss=1</link>
<description><![CDATA[
Developmental biology requires rapid embryo injections and screening. We applied new affordable high-resolution 3D-printing to create five easily modifiable stamp-mold tools that greatly increase injection and screening speed, while simultaneously reducing the harmful aspects of these processes. We designed two stamps that use different approaches to improve the injection efficiency for two different types of embryo, first for embryos from the snail Crepidula fornicata, and second, for those from the spider Parasteatoda tepidariorum. Both drastically improved injection speeds and embryo survival rates, even in novice hands. The other three tools were designed for rapid side-by-side organism orientating and comparison. The first screening tool allows for optimal imaging in Xenopus laevis tadpoles, while the second and third facilitate rapid high-throughput screening of Xenopus tropicalis tadpoles and Danio rerio juveniles, respectively. These designs can act as templates for many injection or screening applications.
]]></description>
<dc:creator>Truchado-Garcia, M.</dc:creator>
<dc:creator>Harland, R. M.</dc:creator>
<dc:creator>Abrams, M. J.</dc:creator>
<dc:date>2018-07-25</dc:date>
<dc:identifier>doi:10.1101/376657</dc:identifier>
<dc:title><![CDATA[3D-printable tools for developmental biology: Improving embryo injection and screening techniques through 3D-printing technology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-07-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/388470v1?rss=1">
<title>
<![CDATA[
Flexibly-oriented double Cdc45-MCM-GINS intermediates during eukaryotic replicative helicase maturation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/388470v1?rss=1</link>
<description><![CDATA[
The core of the eukaryotic helicase MCM is loaded as an inactive double hexamer (DH). How it is assembled into two active Cdc45-MCM-GINS (CMG) helicases remains elusive. Here, we report that at the onset of S phase, both Cdc45 and GINS are loaded as dimers onto MCM DH, resulting in formation of double CMG (d-CMG). As S phase proceeds, d-CMGs gradually mature into two single CMG-centered replisome progression complexes (RPCs). Mass spectra reveal that RPA and DNA Pol /primase co-purify exclusively with RPCs, but not with d-CMGs. Consistently, d-CMGs are not able to catalyze either the unwinding or de novo DNA synthesis, while RPCs can do both. Using single-particle electron microscopy, we have obtained 2D class averages of d-CMGs. Compared to MCM DHs, they display heterogeneous, flexibly orientated and partially loosened conformations with changed interfaces. The dumbbell-shaped d-CMGs are mediated by Ctf4, while other types of d-CMGs are independent of Ctf4. These data suggest CMG dimers as bona fide intermediates during MCM maturation, providing an additional quality control for symmetric origin activation and bidirectional replication.
]]></description>
<dc:creator>Liu, L.</dc:creator>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Zhang, J.</dc:creator>
<dc:creator>Wang, J.-H.</dc:creator>
<dc:creator>Cao, Q.</dc:creator>
<dc:creator>Li, Z.</dc:creator>
<dc:creator>Campbell, J. L.</dc:creator>
<dc:creator>Dong, M.</dc:creator>
<dc:creator>Lou, H.</dc:creator>
<dc:date>2018-08-09</dc:date>
<dc:identifier>doi:10.1101/388470</dc:identifier>
<dc:title><![CDATA[Flexibly-oriented double Cdc45-MCM-GINS intermediates during eukaryotic replicative helicase maturation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/388579v1?rss=1">
<title>
<![CDATA[
Fluorescence-Based Detection of Fusion State on a Cryo-EM Grid using Correlated Cryo-Fluorescence and Cryo-Electron Microscopy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/388579v1?rss=1</link>
<description><![CDATA[
Correlated light and electron microscopy (CLEM) has become a popular technique for combining the protein-specific labeling of fluorescence with electron microscopy, both at room and cryogenic temperatures. Fluorescence applications at cryo-temperature have typically been limited to localization of tagged protein oligomers due to known issues of extended triplet state duration, spectral shifts, and reduced photon capture through cryo-CLEM objectives. Here, we consider fluorophore characteristics and behaviors that could enable more extended applications. We describe how dialkylcarbocanine DiD and its autoquenching by resonant energy transfer can be used to distinguish the fusion state of a lipid bilayer at cryo-temperatures. By adapting an established fusion assay to work under cryo-CLEM conditions, we identified areas of fusion between influenza virus-like particles and fluorescently labeled lipid vesicles on a cryo-EM grid. This result demonstrates that cryo-CLEM can be used to localize functions in addition to tagged proteins, and that fluorescence autoquenching by resonant energy transfer can be incorporated successfully into cryo-CLEM approaches. In the case of membrane fusion applications, this method provides both an orthogonal confirmation of functional state independent of the morphological description from cryo-EM and a way to bridge room-temperature kinetic assays and the cryo-EM images.
]]></description>
<dc:creator>Metskas, L. A.</dc:creator>
<dc:creator>Briggs, J. A. G.</dc:creator>
<dc:date>2018-08-10</dc:date>
<dc:identifier>doi:10.1101/388579</dc:identifier>
<dc:title><![CDATA[Fluorescence-Based Detection of Fusion State on a Cryo-EM Grid using Correlated Cryo-Fluorescence and Cryo-Electron Microscopy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/389296v1?rss=1">
<title>
<![CDATA[
One read per cell per gene is optimal for single-cell RNA-Seq 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/389296v1?rss=1</link>
<description><![CDATA[
An underlying question for virtually all single-cell RNA sequencing experiments is how to allocate the limited sequencing budget: deep sequencing of a few cells or shallow sequencing of many cells? A mathematical framework reveals that, for estimating many important gene properties, the optimal allocation is to sequence at the depth of one read per cell per gene. Interestingly, the corresponding optimal estimator is not the widely-used plugin estimator but one developed via empirical Bayes.
]]></description>
<dc:creator>Zhang, M. J.</dc:creator>
<dc:creator>Ntranos, V.</dc:creator>
<dc:creator>Tse, D.</dc:creator>
<dc:date>2018-08-09</dc:date>
<dc:identifier>doi:10.1101/389296</dc:identifier>
<dc:title><![CDATA[One read per cell per gene is optimal for single-cell RNA-Seq]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/390617v1?rss=1">
<title>
<![CDATA[
Divergent methyl-coenzyme M reductase genes in a deep-subseafloor Archaeoglobi 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/390617v1?rss=1</link>
<description><![CDATA[
The methyl-coenzyme M reductase (MCR) complex is a key enzyme in archaeal methane generation and has recently been proposed to also be involved in the oxidation of short-chain hydrocarbons including methane, butane and potentially propane. The number of archaeal clades encoding the MCR complex continues to grow, suggesting that this complex was inherited from an ancient ancestor, or has undergone extensive horizontal gene transfer. Expanding the representation of MCR-encoding lineages through metagenomic approaches will help resolve the evolutionary history of this complex. Here, a near-complete Archaeoglobi metagenome-assembled genome (MAG; rG16) was recovered from the deep subseafloor along the Juan de Fuca Ridge flank that encodes two divergent McrABG operons similar to those found in Candidatus Bathyarchaeota and Candidatus Syntrophoarchaeum MAGs. rG16 is basal to members of the class Archaeoglobi, and encodes the genes for {beta}-oxidation, potentially allowing an alkanotrophic metabolism similar to that proposed for Ca. Syntrophoarchaeum. rG16 also encodes a respiratory electron transport chain that can potentially utilize nitrate, iron, and sulfur compounds as electron acceptors. As the first Archaeoglobi with the MCR complex, rG16 extends our understanding of the evolution and distribution of novel MCR encoding lineages among the Archaea.
]]></description>
<dc:creator>Boyd, J.</dc:creator>
<dc:creator>Jungbluth, S.</dc:creator>
<dc:creator>Leu, A.</dc:creator>
<dc:creator>Evans, P.</dc:creator>
<dc:creator>Woodcroft, B.</dc:creator>
<dc:creator>Chadwick, G.</dc:creator>
<dc:creator>Orphan, V.</dc:creator>
<dc:creator>Amend, J.</dc:creator>
<dc:creator>Rappe, M.</dc:creator>
<dc:creator>Tyson, G.</dc:creator>
<dc:date>2018-08-13</dc:date>
<dc:identifier>doi:10.1101/390617</dc:identifier>
<dc:title><![CDATA[Divergent methyl-coenzyme M reductase genes in a deep-subseafloor Archaeoglobi]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/391243v1?rss=1">
<title>
<![CDATA[
An efficient genome editing strategy to generate putative null mutants in Caenorhabditis elegans using CRISPR/Cas9 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/391243v1?rss=1</link>
<description><![CDATA[
Null mutants are essential for analyzing gene function. Here, we describe a simple and efficient method to generate Caenorhabditis elegans null mutants using CRISPR/Cas9 and short single stranded DNA oligo repair templates to insert a universal 43-nucleotide-long stop knock-in (STOP-IN) cassette into the early exons of target genes. This cassette has stop codons in all three reading frames and leads to frameshifts, which will generate putative null mutations regardless of the reading frame of the insertion position in exons. The STOP-IN cassette also contains an exogenous Cas9 target site that allows further genome editing and provides a unique sequence that simplifies the identification of successful insertion events via PCR. As a proof of concept, we inserted the STOP-IN cassette right at a Cas9 target site in aex-2 to generate new putative null alleles by injecting preassembled Cas9 ribonucleoprotein and a short synthetic single stranded DNA repair template containing the STOP-IN cassette and two 35-nucleotide-long homology arms identical to the sequences flanking the Cas9 cut site. We showed that these new aex-2 alleles phenocopied an existing loss-of-function allele of aex-2. We further showed that the new aex-2 null alleles could be reverted back to the wild-type sequence by targeting exogenous Cas9 cut site included in the STOP-IN cassette and providing a single stranded wild-type DNA repair oligo. We applied our STOP-IN method to generate new putative null mutants for additional 20 genes, including three pharyngeal muscle-specific genes (clik-1, clik-2, and clik-3), and reported a high insertion rate (46%) based on the animals we screened. We showed that null mutations of clik-2 cause recessive lethality with a severe pumping defect and clik-3 null mutants have a mild pumping defect, while clik-1 is dispensable for pumping. We expect that the knock-in method using the STOP-IN cassette will facilitate the generation of new null mutants to understand gene function in C. elegans and other genetic model organisms.nnSummaryWe report a simple and efficient CRISPR/Cas9 genome editing strategy to generate putative null C. elegans mutants by inserting a small universal stop knock-in (STOP-IN) cassette with stop codons in three frames and frameshifts. The strategy is cloning-free, with the mixture consisting of preassembled Cas9 ribonucleoprotein and single stranded repair DNA oligos directly injected into gonads of adult C. elegans. The universal STOP-IN cassette also contains a unique sequence that simplifies detection of successful knock-in events via PCR and an exogenous Cas9 target sequence that allows further genome editing.
]]></description>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Wang, H.</dc:creator>
<dc:creator>Park, H.</dc:creator>
<dc:creator>Liu, J.</dc:creator>
<dc:date>2018-08-13</dc:date>
<dc:identifier>doi:10.1101/391243</dc:identifier>
<dc:title><![CDATA[An efficient genome editing strategy to generate putative null mutants in Caenorhabditis elegans using CRISPR/Cas9]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/391599v1?rss=1">
<title>
<![CDATA[
Maintaining trunk neural crest cells as crestospheres 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/391599v1?rss=1</link>
<description><![CDATA[
Neural crest cells have broad migratory and differentiative ability that differs according to their axial level of origin. However, their transient nature has limited understanding of their stem cell and self-renewal properties. While an in vitro culture method has made it possible to maintain cranial neural crest cells as self-renewing multipotent crestospheres (Kerosuo et al., 2015), these same conditions failed to preserve trunk neural crest in a stem-like state. Here we optimize culture conditions for maintenance of trunk crestospheres, comprised of both neural crest stem and progenitor cells. Trunk crestospheres display elevated expression of neural crest cell markers as compared to those characteristic of neural tube or mesodermal fates. Moreover, trunk crestospheres have increased expression of trunk-related markers as compared to cranial genes. Finally, we use lentiviral transduction as a tool to manipulate gene expression in trunk crestospheres. Taken together, this method enables long-term in vitro maintenance and manipulation of trunk neural crest cells in a premigratory stem or early progenitor state to probe the mechanisms underlying their stemness and lineage decisions.nnHighlightsO_LITrunk-derived multipotent neural crest stem cells can be cultured as crestospheresnC_LIO_LITrunk-derived crestospheres require different conditions than cranialnC_LIO_LITrunk crestospheres consist of neural crest stem and progenitor cellsnC_LIO_LITrunk crestospheres can be efficiently transduced using lentiviral vectorsnC_LI
]]></description>
<dc:creator>Mohlin, S.</dc:creator>
<dc:creator>Kunttas, E.</dc:creator>
<dc:creator>Persson, C. U.</dc:creator>
<dc:creator>Abdel-Haq, R.</dc:creator>
<dc:creator>Castillo, A.</dc:creator>
<dc:creator>Murko, C.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>Kerosuo, L.</dc:creator>
<dc:date>2018-08-14</dc:date>
<dc:identifier>doi:10.1101/391599</dc:identifier>
<dc:title><![CDATA[Maintaining trunk neural crest cells as crestospheres]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/391896v1?rss=1">
<title>
<![CDATA[
Reading at the speed of speech: the rate of eye movements aligns with auditory language processing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/391896v1?rss=1</link>
<description><![CDATA[
Across languages, the speech signal is characterized by a predominant modulation of the amplitude spectrum between about 4.3-5.5Hz, reflecting the production and processing of linguistic information chunks (syllables, words) every [~]200ms. Interestingly, [~]200ms is also the typical duration of eye fixations during reading. Prompted by this observation, we demonstrate that German readers sample written text at [~]5Hz. A subsequent meta-analysis with 142 studies from 14 languages replicates this result, but also shows that sampling frequencies vary across languages between 3.9Hz and 5.2Hz, and that this variation systematically depends on the complexity of the writing systems (character-based vs. alphabetic systems, orthographic transparency). Finally, we demonstrate empirically a positive correlation between speech spectrum and eye-movement sampling in low-skilled readers. Based on this convergent evidence, we propose that during reading, our brains linguistic processing systems imprint a preferred processing rate, i.e., the rate of spoken language production and perception, onto the oculomotor system.
]]></description>
<dc:creator>Gagl, B.</dc:creator>
<dc:creator>Golch, J.</dc:creator>
<dc:creator>Hawelka, S.</dc:creator>
<dc:creator>Sassenhagen, J.</dc:creator>
<dc:creator>Poeppel, D.</dc:creator>
<dc:creator>Fiebach, C. J.</dc:creator>
<dc:date>2018-08-14</dc:date>
<dc:identifier>doi:10.1101/391896</dc:identifier>
<dc:title><![CDATA[Reading at the speed of speech: the rate of eye movements aligns with auditory language processing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/392142v1?rss=1">
<title>
<![CDATA[
Epigenetic inactivation of miR-203 as a key step in neural crest epithelial-to-mesenchymal transition 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/392142v1?rss=1</link>
<description><![CDATA[
miR-203 is a tumor-suppressor microRNA with known functions in cancer metastasis. Here, we explore its normal developmental role in the context of neural crest development. As neural crest cells undergo an epithelial-to-mesenchymal transition to emigrate from the neural tube, miR-203 displays a reciprocal expression pattern with key regulators of neural crest delamination, Phf12 and Snail2, and interacts with their 3UTRs. Ectopic maintenance of miR-203 inhibits neural crest migration, whereas its functional inhibition using a "sponge" vector promotes premature neural crest delamination. Bisulfite sequencing further shows that epigenetic repression of miR-203 is mediated by the de novo DNA methyltransferase DNMT3B, whose recruitment to regulatory regions on the miR-203 locus is directed by SNAIL2 in a negative feedback loop. These findings reveal an important role for miR-203 in an epigenetic-microRNA regulatory network that influences the timing of neural crest delamination.nnSummary statementThe EMT is a highly conserved process, involving similar levels of regulation in both neural crest and cancer cells. Our work shows an epigenetic-miRNA-gene regulatory circuit, conserved in cancer, which controls the timing of neural crest EMT as well.
]]></description>
<dc:creator>Sanchez-Vasquez, E.</dc:creator>
<dc:creator>Bronner, M.</dc:creator>
<dc:creator>Strobl-Mazzulla, P. H.</dc:creator>
<dc:date>2018-08-14</dc:date>
<dc:identifier>doi:10.1101/392142</dc:identifier>
<dc:title><![CDATA[Epigenetic inactivation of miR-203 as a key step in neural crest epithelial-to-mesenchymal transition]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/399881v1?rss=1">
<title>
<![CDATA[
RAD51 AND MITOTIC FUNCTION OF MUS81 ARE ESSENTIAL FOR RECOVERY FROM LOW-DOSE OF CAMPTOTHECIN IN THE ABSENCE OF THE WRN EXONUCLEASE 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/399881v1?rss=1</link>
<description><![CDATA[
Stabilisation of the stalled replication fork is crucial to prevent excessive fork reversal or degradation, which can undermine genome integrity. The WRN protein is a human RecQ helicase that participates in the processing and recovery of perturbed replication forks. WRN is unique among the other human RecQ family members to possess exonuclease activity. However, the biological role of the WRN exonuclease is poorly defined, and little is known about an involvement in the response to perturbed replication. Recently, the WRN exonuclease has been linked to protection of stalled forks from MRE11-dependent degradation in response to clinically-relevant nanomolar doses of the Topoisomerase I inhibitor camptothecin. Alternative processing of perturbed forks has been associated to chemoresistance of BRCA-deficient cancer cells, thus, we used WRN exonuclease-deficiency as a model to investigate the fate of perturbed replication forks undergoing degradation, but in a BRCA wild-type condition. We find that, upon nanomolar doses of camptothecin, loss of WRN exonuclease stimulates fork inactivation and accumulation of parental gaps, which engages RAD51. Such alternative mechanism affects reinforcement of CHK1 phosphorylation and causes persistence of RAD51 during recovery from treatment. Notably, in WRN exonuclease-deficient cells, persistence of RAD51 correlates with elevated mitotic phosphorylation of MUS81 at Serine 87, which is essential to avoid accumulation of mitotic abnormalities. Altogether, these findings indicate that aberrant fork degradation, in the presence of a wild-type RAD51 axis, stimulates RAD51-mediated post-replicative repair and engagement of the MUS81 complex to limit genome instability and cell death.nnAUTHOR SUMMARYCorrect progression of the molecular machine copying the chromosomes is threatened by multiple causes that induce its delay or arrest. Once the replication machinery is arrested, the cell needs to stabilise it to prevent DNA damage. Many proteins contribute to this task and the Werners syndrome protein, WRN, is one of them.nnDefining what happens to replication machineries when they are blocked is highly relevant. Indeed, destabilised replication machineries may form upon treatment with anticancer drugs and influence the efficacy of some of them in specific genetic backgrounds. We used cells that lack one of the two enzymatic functions of WRN, the exonuclease activity, to investigate the fate of destabilised replication machineries. Our data show that they are handled by a repair pathway normally involved in fixing DNA breaks but, in this case, recruited to deal with regions of the genome that are left unreplicated after their destabilisation. This alternative mechanism involves a protein, RAD51, which tries to copy DNA from the sister chromosome. In so doing, however, RAD51 produces a lot of DNA interlinking that requires upregulation of a complex, called MUS81/EME1, which resolves this interlinking prior cell division and prevents accumulation of mitotic defects and cell death.
]]></description>
<dc:creator>Pichierri, P.</dc:creator>
<dc:creator>Aiello, F. A.</dc:creator>
<dc:creator>Palma, A.</dc:creator>
<dc:creator>Malacaria, E.</dc:creator>
<dc:creator>Zheng, L.</dc:creator>
<dc:creator>Campbell, J. L.</dc:creator>
<dc:creator>Shen, B.</dc:creator>
<dc:creator>Franchitto, A.</dc:creator>
<dc:date>2018-08-25</dc:date>
<dc:identifier>doi:10.1101/399881</dc:identifier>
<dc:title><![CDATA[RAD51 AND MITOTIC FUNCTION OF MUS81 ARE ESSENTIAL FOR RECOVERY FROM LOW-DOSE OF CAMPTOTHECIN IN THE ABSENCE OF THE WRN EXONUCLEASE]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/406389v1?rss=1">
<title>
<![CDATA[
Simulations suggest a constrictive force is required for Gram-negative bacterial cell division 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/406389v1?rss=1</link>
<description><![CDATA[
To divide, Gram-negative bacterial cells must remodel their peptidoglycan cell wall to a smaller and smaller radius at the division site, but how this process occurs remains debated. While the tubulin homolog FtsZ is thought to generate a constrictive force, it has also been proposed that cell wall remodeling alone is sufficient to drive membrane constriction, possibly via a make-before-break mechanism in which new hoops of cell wall are made inside the existing hoops (make) before bonds in the existing wall are cleaved (break). Previously, we constructed software, REMODELER 1, to simulate cell wall remodeling in rod-shaped bacteria during growth. Here, we used this software as the basis for an expanded simulation system, REMODELER 2, which we used to explore different mechanistic models of cell wall division. We found that simply organizing the cell wall synthesis complexes at the midcell was not sufficient to cause wall invagination, even with the implementation of a make-before-break mechanism. Applying a constrictive force at the midcell could drive division if the force was sufficiently large to initially constrict the midcell into a compressed state before new hoops of relaxed cell wall were incorporated between existing hoops. Adding a make-before-break mechanism could drive division with a smaller constrictive force sufficient to bring the midcell peptidoglycan into a relaxed, but not necessarily compressed, state.
]]></description>
<dc:creator>Nguyen, L. T.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>Ding, H. J.</dc:creator>
<dc:creator>Kaplan, M.</dc:creator>
<dc:creator>Yao, Q.</dc:creator>
<dc:creator>Chang, Y.-W.</dc:creator>
<dc:creator>Beeby, M.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2018-09-01</dc:date>
<dc:identifier>doi:10.1101/406389</dc:identifier>
<dc:title><![CDATA[Simulations suggest a constrictive force is required for Gram-negative bacterial cell division]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/406454v1?rss=1">
<title>
<![CDATA[
Quantifying the Entropic and Energetic Effects of Linker Length and Rigidity within Synthetic HIV-1 Antibodies designed to Bind Bivalently to Env Spikes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/406454v1?rss=1</link>
<description><![CDATA[
Due to the low density of envelope (Env) spikes on the surface of HIV-1, neutralizing IgG antibodies rarely bind bivalently using both antigen-binding arms (Fabs) to crosslink between spikes (inter-spike crosslinking), instead resorting to weaker monovalent binding that is more sensitive to Env mutations. Synthetic antibodies designed to bivalently bind a single Env trimer (intra-spike crosslinking) were previously shown to exhibit increased neutralization potencies. In initial work, diFabs joined by varying lengths of rigid double-stranded DNA (dsDNA) were considered. Anticipating future experiments to improve synthetic antibodies, we investigate whether linkers with different rigidities could enhance diFab potency by modeling DNA-Fabs containing different combinations of rigid dsDNA and flexible single-stranded DNA (ssDNA) and characterizing their neutralization potential. Model predictions suggest that while a long flexible polymer may be capable of bivalent binding, it exhibits weak neutralization due to the large loss in entropic degrees of freedom when both Fabs are bound. In contrast, the strongest neutralization potencies are predicted to require a rigid linker that optimally spans the distance between two Fab binding sites on an Env trimer, and avidity can be further boosted by incorporating more Fabs into these constructs. These results inform the design of multivalent anti-HIV-1 therapeutics that utilize avidity effects to remain potent against HIV-1 in the face of the rapid mutation of Env spikes.nnSignificanceIgG antibodies utilize avidity to increase their apparent affinities through simultaneous binding of two antigen-binding Fabs - if one Fab dissociates from an antigen, the other Fab can remain attached, allowing rebinding. HIV-1 foils this strategy by having few, and highly-separated, Envelope spike targets for antibodies, forcing most IgGs to bind monovalently. Here we develop a statistical mechanics model of synthetic diFabs joined by DNA linkers of different lengths and flexibilities. This framework enables us to translate the energetic and entropic effects of the linker into the neutralization potency of a diFab. We demonstrate that the avidity of multivalent binding is enhanced by using rigid linkers or including additional Fabs capable of simultaneous binding, providing the means to quantitatively predict the potencies of other antibody designs.
]]></description>
<dc:creator>Galimidi, R. P.</dc:creator>
<dc:creator>Einav, T.</dc:creator>
<dc:creator>Gnanapragasam, P. N. P.</dc:creator>
<dc:creator>Joshi, D. S.</dc:creator>
<dc:creator>Lynch, A. M.</dc:creator>
<dc:creator>Yazdi, S.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2018-09-03</dc:date>
<dc:identifier>doi:10.1101/406454</dc:identifier>
<dc:title><![CDATA[Quantifying the Entropic and Energetic Effects of Linker Length and Rigidity within Synthetic HIV-1 Antibodies designed to Bind Bivalently to Env Spikes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/407882v1?rss=1">
<title>
<![CDATA[
Draxin alters laminin expression during basement membrane reorganization to control cranial neural crest EMT 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/407882v1?rss=1</link>
<description><![CDATA[
Premigratory neural crest cells arise within the dorsal neural tube and subsequently undergo an epithelial-to-mesenchymal transition (EMT) to leave the neuroepithelium and initiate migration. Draxin is a Wnt modulator that has been shown to control the timing of cranial neural crest EMT. Here we show that this process is accompanied by three stages of remodeling of the basement membrane protein laminin, from regression to expansion and channel formation. Loss of Draxin results in blocking laminin remodeling at the regression stage, whereas ectopic maintenance of Draxin blocks remodeling at the expansion stage. The latter effect is rescued by addition of Snail2, previously shown to be downstream of Draxin. Our results demonstrate an essential function for the Wnt modulator Draxin in regulating basement membrane remodeling during cranial neural crest EMT.nnHIGHLIGHTSO_LICranial neural crest migrate through a laminin-rich basement membrane channelnC_LIO_LIPerturbation of Draxin, a Wnt antagonist, alters laminin channel formationnC_LIO_LIDraxins effect on laminin channel formation is largely mediated by Snail2nC_LI
]]></description>
<dc:creator>Hutchins, E. J.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:date>2018-09-03</dc:date>
<dc:identifier>doi:10.1101/407882</dc:identifier>
<dc:title><![CDATA[Draxin alters laminin expression during basement membrane reorganization to control cranial neural crest EMT]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/412114v1?rss=1">
<title>
<![CDATA[
A data-driven approach to the automated study of cross-species homologies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/412114v1?rss=1</link>
<description><![CDATA[
Behavioral neuroscience has made great strides in developing animal models of human behavior and psychiatric disorders. Animal models allow for the formulation of hypotheses regarding the mechanisms underlying psychiatric disorders, and the opportunity to test these hypotheses using procedures that are too invasive for human participants. However, recent scientific reviews have highlighted the low success rate of translating results from animal models into clinical interventions in humans. A potential roadblock is that bidirectional functional mappings between the human and rodent brain are incomplete. To narrow this gap, we created a framework, Neurobabel, for performing large-scale automated synthesis of human neuroimaging data and behavioral neuroscience data. By leveraging the semantics of how researchers within each field describe their studies, this framework enables region to region mapping of brain regions across species, as well as cross-species mapping of psychological functions. As a proof of concept, we utilize the framework to create a functional cross-species mapping between the amygdala and hippocampus for fear-related and spatial memories, respectively. We then proceed to address two open questions in the field: (1) Do rodents have a dorsolateral prefrontal cortex? (2) Which human brain region corresponds to the rodent prelimbic cortex?
]]></description>
<dc:creator>Pauli, W. M.</dc:creator>
<dc:date>2018-09-09</dc:date>
<dc:identifier>doi:10.1101/412114</dc:identifier>
<dc:title><![CDATA[A data-driven approach to the automated study of cross-species homologies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/423301v1?rss=1">
<title>
<![CDATA[
Extended hopanoid lipids promote bacterial motility, surface attachment, and root nodule development in the Bradyrhizobium diazoefficiens-Aeschynomene afraspera symbiosis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/423301v1?rss=1</link>
<description><![CDATA[
Hopanoids are steroid-like bacterial lipids that enhance membrane rigidity and promote bacterial growth under diverse stresses. Hopanoid biosynthesis genes are conserved in nitrogen-fixing plant symbionts, and we previously found that the extended (C35) class of hopanoids in Bradyrhizobium diazoefficiens are required for efficient symbiotic nitrogen fixation in the tropical legume host Aeschynomene afraspera. Here we demonstrate that the nitrogen fixation defect conferred by extended loss can fully be explained by a reduction in root nodule sizes rather than per-bacteroid nitrogen fixation levels. Using a single-nodule tracking approach to track A. afraspera nodule development, we provide a quantitative model of root nodule development in this host, uncovering both the baseline growth parameters for wild-type nodules and a surprising heterogeneity of extended hopanoid mutant developmental phenotypes. These phenotypes include a delay in root nodule initiation and presence of a subpopulation of nodules with slow growth rates and low final volumes, which are correlated with reduced motility and surface attachment in vitro and lower bacteroid densities in planta, respectively. This work provides a quantitative reference point for understanding the phenotypic diversity of ineffective symbionts in A. afraspera and identifies specific developmental stages affected by extended hopanoid loss for future mechanistic work.
]]></description>
<dc:creator>Belin, B. J.</dc:creator>
<dc:creator>Tookmanian, E. T.</dc:creator>
<dc:creator>de Anda, J.</dc:creator>
<dc:creator>Wong, G.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2018-09-21</dc:date>
<dc:identifier>doi:10.1101/423301</dc:identifier>
<dc:title><![CDATA[Extended hopanoid lipids promote bacterial motility, surface attachment, and root nodule development in the Bradyrhizobium diazoefficiens-Aeschynomene afraspera symbiosis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/423384v1?rss=1">
<title>
<![CDATA[
The dormancy specific regulator, SutA, is an intrinsically-disordered protein that modulates transcription initiation in Pseudomonas aeruginosa 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/423384v1?rss=1</link>
<description><![CDATA[
Though bacteria in nature are often nutritionally limited and growing slowly, most of our understanding of core cellular processes such as transcription comes from studies in a handful of model organisms doubling rapidly under nutrient-replete conditions. We previously identified a small protein of unknown function, called SutA, in a global screen of proteins synthesized in Pseudomonas aeruginosa under growth arrest (Babin BM, et al. (2016) SutA is a bacterial transcription factor expressed during slow growth in Pseudomonas aeruginosa. PNAS 113(5):E597-605). SutA binds RNA polymerase (RNAP), causing widespread changes in gene expression, including upregulation of the ribosomal RNA (rRNA) genes. Here, using biochemical and structural methods, we examine how SutA interacts with RNAP and the functional consequences of these interactions. We show that SutA consists of a central -helix with unstructured N- and C-terminal tails, and binds to the {beta}1 domain of RNAP. It activates transcription from the P. aeruginosa rrn promoter by both the housekeeping sigma factor holoenzyme (E{sigma}70) and the general stress response sigma factor holoenzyme (E{sigma}S) in vitro, and its N-terminal tail is required for activation in both holoenzyme contexts. However, we find that the interaction between SutA and each holoenzyme is distinct, with the SutA C-terminal tail and an acidic loop unique to {sigma}70 playing the determining roles in these differences. Our results add SutA to a growing list of transcription regulators that use their intrinsically disordered regions to remodel transcription complexes.nnSIGNIFICANCELittle is known about how bacteria regulate their activities during periods of dormancy, yet growth arrest dominates bacterial existence in most environments and is directly relevant to the problem of physiological antibiotic tolerance. Though much is known about transcription in the model organism, Escherichia coli, even there, our understanding of gene expression during dormancy is incomplete. Here we explore how transcription under growth arrest is modulated in Pseudomonas aeruginosa by the small acidic protein, SutA. We show that SutA binds to RNA polymerase and controls transcription by a mechanism that is distinct from other known regulators. Our work underscores the potential for fundamental, mechanistic discovery in this important and understudied realm of bacterial physiology.
]]></description>
<dc:creator>Bergkessel, M.</dc:creator>
<dc:creator>Babin, B. M.</dc:creator>
<dc:creator>VanderVelde, D.</dc:creator>
<dc:creator>Sweredoski, M.</dc:creator>
<dc:creator>Moradian, A.</dc:creator>
<dc:creator>Eggleston-Rangel, R.</dc:creator>
<dc:creator>Hess, S.</dc:creator>
<dc:creator>Tirrell, D.</dc:creator>
<dc:creator>Artsimovitch, I.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2018-09-20</dc:date>
<dc:identifier>doi:10.1101/423384</dc:identifier>
<dc:title><![CDATA[The dormancy specific regulator, SutA, is an intrinsically-disordered protein that modulates transcription initiation in Pseudomonas aeruginosa]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/424416v1?rss=1">
<title>
<![CDATA[
Transsynaptic interactions between IgSF proteins DIP-α and Dpr10 are required for motor neuron targeting specificity in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/424416v1?rss=1</link>
<description><![CDATA[
The Drosophila larval neuromuscular system provides an ideal context in which to study synaptic partner choice, because it contains a small number of pre- and postsynaptic cells connected in an invariant pattern. The discovery of interactions between two subfamilies of IgSF cell surface proteins, the Dprs and the DIPs, provided new candidates for cellular labels controlling synaptic specificity. Here we show that DIP- is expressed by two identified motor neurons, while its binding partner Dpr10 is expressed by postsynaptic muscle targets. Removal of either DIP- or Dpr10 results in loss of specific axonal branches and NMJs formed by one motor neuron, MNISN-1s, while other branches of the MNISN-1s axon develop normally. The temporal and spatial expression pattern of dpr10 correlates with muscle innervation by MNISN-1s during embryonic development. We propose a model whereby DIP- and Dpr10 on opposing synaptic partners interact with each other to generate proper motor neuron connectivity.
]]></description>
<dc:creator>Ashley, J.</dc:creator>
<dc:creator>Sorrentino, V.</dc:creator>
<dc:creator>Nagarkar-Jaiswal, S.</dc:creator>
<dc:creator>Tan, L.</dc:creator>
<dc:creator>Xu, S.</dc:creator>
<dc:creator>Xiao, Q.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:creator>Carrillo, R. A.</dc:creator>
<dc:date>2018-09-21</dc:date>
<dc:identifier>doi:10.1101/424416</dc:identifier>
<dc:title><![CDATA[Transsynaptic interactions between IgSF proteins DIP-α and Dpr10 are required for motor neuron targeting specificity in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/425611v1?rss=1">
<title>
<![CDATA[
Collection of continuous rotation MicroED Data from Ion Beam Milled Crystals of Any Size 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/425611v1?rss=1</link>
<description><![CDATA[
Microcrystal electron diffraction (MicroED) allows for macromolecular structure solution from nanocrystals. To create crystals of suitable size for MicroED data collection, sample preparation typically involves sonication or pipetting a slurry of crystals from a crystallization drop. The resultant crystal fragments are fragile and the quality of the data that can be obtained from them is sensitive to subsequent sample preparation for cryoEM as interactions in the water-air interface can damage crystals during blotting. Here, we demonstrate the use of a focused ion beam to generate lamellae of macromolecular protein crystals for continuous rotation MicroED that are of ideal thickness, easy to locate, and require no blotting optimization. In this manner, crystals of nearly any size may be scooped and milled to ideal dimensions prior to data collection, thus streamlining the methodology for sample preparation for MicroED.
]]></description>
<dc:creator>Martynowycz, M.</dc:creator>
<dc:creator>Zhao, W.</dc:creator>
<dc:creator>Hattne, J.</dc:creator>
<dc:creator>Jensen, G.</dc:creator>
<dc:creator>Gonen, T.</dc:creator>
<dc:date>2018-09-24</dc:date>
<dc:identifier>doi:10.1101/425611</dc:identifier>
<dc:title><![CDATA[Collection of continuous rotation MicroED Data from Ion Beam Milled Crystals of Any Size]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/428300v1?rss=1">
<title>
<![CDATA[
Architectural Principles for Characterizing the Performance of Sequestration Feedback Networks 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/428300v1?rss=1</link>
<description><![CDATA[
As we begin to design increasingly complex synthetic biomolecular systems, it is essential to develop rational design methodologies that yield predictable circuit performance. Here we apply theoretical tools from the theory of control and dynamical systems to yield practical insights into the architecture and function of a particular class of biological feedback circuit. Specifically, we show that it is possible to analytically characterize both the operating regime and performance tradeoffs of a sequestration feedback circuit architecture. Further, we demonstrate how these principles can be applied to inform the design process of a particular synthetic feedback circuit.
]]></description>
<dc:creator>Olsman, N.</dc:creator>
<dc:creator>Xiao, F.</dc:creator>
<dc:creator>Doyle, J. C.</dc:creator>
<dc:date>2018-09-27</dc:date>
<dc:identifier>doi:10.1101/428300</dc:identifier>
<dc:title><![CDATA[Architectural Principles for Characterizing the Performance of Sequestration Feedback Networks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/428508v1?rss=1">
<title>
<![CDATA[
Molecular basis of human asparagine synthetase inhibitor specificity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/428508v1?rss=1</link>
<description><![CDATA[
Expression of the enzyme human asparagine synthetase (ASNS) promotes metastatic progression in breast cancer, which affects L-asparagine levels and tumor cell invasiveness. Human ASNS has therefore emerged as a bona fide drug target for cancer therapy. We have reported a slow-onset, tight binding ASNS inhibitor with nanomolar affinity, but our compound exhibits poor cell permeability. On the other hand, we show here that this inhibitor exhibits remarkable selectivity for the human ASNS in HCT-116 cell lysates. By determining the first high-resolution (1.85 [A]) X-ray crystal structure for human ASNS, we have built a computational model of the enzyme complexed to our inhibitor, which provides the first insights into the intermolecular interactions mediating specificity. These findings should facilitate the development of a second generation of ASNS inhibitors, leading to the discovery of drugs to prevent metastasis.
]]></description>
<dc:creator>Zhu, W.</dc:creator>
<dc:creator>Radadiya, A.</dc:creator>
<dc:creator>Bisson, C.</dc:creator>
<dc:creator>Nordin, B.</dc:creator>
<dc:creator>Baumann, P.</dc:creator>
<dc:creator>Imasaki, T.</dc:creator>
<dc:creator>Wenzel, S.</dc:creator>
<dc:creator>Sedelnikova, S.</dc:creator>
<dc:creator>Berry, A.</dc:creator>
<dc:creator>Nomanbhoy, T.</dc:creator>
<dc:creator>Kozarich, J.</dc:creator>
<dc:creator>Jin, Y.</dc:creator>
<dc:creator>Takagi, Y.</dc:creator>
<dc:creator>Rice, D.</dc:creator>
<dc:creator>Richards, N.</dc:creator>
<dc:date>2018-09-29</dc:date>
<dc:identifier>doi:10.1101/428508</dc:identifier>
<dc:title><![CDATA[Molecular basis of human asparagine synthetase inhibitor specificity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/428698v1?rss=1">
<title>
<![CDATA[
Thermophilic Lithotrophy and Phototrophy in an Intertidal, Iron-rich, Geothermal Spring 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/428698v1?rss=1</link>
<description><![CDATA[
Hydrothermal systems, including terrestrial hot springs, contain diverse geochemical conditions that vary over short spatial scales due to progressive interaction between the reducing hydrothermal fluids, the oxygenated atmosphere, and in some cases seawater. At Jinata Onsen, on Shikinejima Island, Japan, an intertidal, anoxic, iron-rich hot spring mixes with the oxygenated atmosphere and seawater over short spatial scales, creating a diversity of chemical potentials and redox pairs over a distance ~10 m. We characterized the geochemical conditions along the outflow of Jinata Onsen as well as the microbial communities present in biofilms, mats, and mineral crusts along its traverse via 16S rDNA amplicon and genome-resolved shotgun metagenomic sequencing. The microbial community changed significantly downstream as temperatures and dissolved iron concentrations decreased and dissolved oxygen increased. Near the spring source, biomass is limited relative to downstream, and primary productivity may be fueled by oxidation of ferrous iron and molecular hydrogen by members of the Zetaproteobacteria and Aquificae. Downstream, the microbial community is dominated by oxygenic Cyanobacteria. Cyanobacteria are abundant and active even at ferrous iron concentrations of ~150 M, which challenges the idea that iron toxicity limited cyanobacterial expansion in Precambrian oceans. Several novel lineages of Bacteria are also present at Jinata Onsen, including previously uncharacterized members of the Chloroflexi and Caldithrichaeota phyla, positioning Jinata Onsen as a valuable site for future characterization of these clades.

ImportanceHigh temperatures and reducing conditions allow hot springs to support microbial communities that are very different from those found elsewhere on the surface of the Earth today; in some ways, these environments and the communities they support can be similar to environments that existed on the early Earth and that may exist on other planets. Here, we describe a novel hot spring system where hot, iron-rich but oxygen-poor water flows into the ocean, supporting a range of unique microbial communities. Metagenomic sequencing recovered many novel microbial lineages, including deep-branching and uniquely thermotolerant members of known groups. Comparison of the biological communities in the upstream part of the hot spring, potentially supported by biological iron and hydrogen oxidizing metabolisms, to downstream microbial mats, supported by oxygenic photosynthesis, provides insight into the potential productivity of life during Proterozoic time and on other planets where oxygenic photosynthesis is not possible.
]]></description>
<dc:creator>Ward, L. M.</dc:creator>
<dc:creator>Idei, A.</dc:creator>
<dc:creator>Nakagawa, M.</dc:creator>
<dc:creator>Ueno, Y.</dc:creator>
<dc:creator>Fischer, W. W.</dc:creator>
<dc:creator>McGlynn, S. E.</dc:creator>
<dc:date>2018-09-27</dc:date>
<dc:identifier>doi:10.1101/428698</dc:identifier>
<dc:title><![CDATA[Thermophilic Lithotrophy and Phototrophy in an Intertidal, Iron-rich, Geothermal Spring]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/439273v1?rss=1">
<title>
<![CDATA[
Signal Transduction in Human Cell Lysate via Dynamic RNA Nanotechnology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/439273v1?rss=1</link>
<description><![CDATA[
Dynamic RNA nanotechnology with small conditional RNAs (scRNAs) offers a promising conceptual approach to introducing synthetic regulatory links into endogenous biological circuits. Here, we use human cell lysate containing functional Dicer and RNases as a testbed for engineering scRNAs for conditional RNA interference (RNAi). scRNAs perform signal transduction via conditional shape change: detection of a subsequence of mRNA input X triggers formation of a Dicer substrate that is processed to yield siRNA output anti-Y targeting independent mRNA Y for destruction. Automated sequence design is performed using the reaction pathway designer within NUPACK to encode this conditional hybridization cascade into the scRNA sequence subject to the sequence constraints imposed by X and Y. Because it is difficult for secondary structure models to predict which subsequences of mRNA input X will be accessible for detection, here we develop the RNAhyb method to experimentally determine accessible windows within the mRNA that are provided to the designer as sequence constraints. We demonstrate the programmability of scRNA regulators by engineering scRNAs for transducing in both directions between two full-length mRNAs X and Y, corresponding to either the forward molecular logic "if X then not Y" (X [boxvl] Y) or the reverse molecular logic "if Y then not X" (Y [boxvl] X). In human cell lysate, we observe a strong OFF/ON conditional response with low crosstalk, corresponding to a {approx}20-fold increase in production of the siRNA output in response to the cognate vs non-cognate full-length mRNA input. Because diverse biological pathways interact with RNA, scRNAs that transduce between detection of endogenous RNA inputs and production of biologically active RNA outputs hold great promise as a synthetic regulatory paradigm.nnnnO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=63 SRC="FIGDIR/small/439273_ufig1.gif" ALT="Figure 1">nView larger version (10K):norg.highwire.dtl.DTLVardef@fb2a0org.highwire.dtl.DTLVardef@98517dorg.highwire.dtl.DTLVardef@e0fe8org.highwire.dtl.DTLVardef@1364f8d_HPS_FORMAT_FIGEXP  M_FIG C_FIG
]]></description>
<dc:creator>Hochrein, L. M.</dc:creator>
<dc:creator>Ge, T. J.</dc:creator>
<dc:creator>Schwarzkopf, M.</dc:creator>
<dc:creator>Pierce, N. A.</dc:creator>
<dc:date>2018-10-11</dc:date>
<dc:identifier>doi:10.1101/439273</dc:identifier>
<dc:title><![CDATA[Signal Transduction in Human Cell Lysate via Dynamic RNA Nanotechnology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/440453v1?rss=1">
<title>
<![CDATA[
Coupled Reaction Networks for Noise Suppression 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/440453v1?rss=1</link>
<description><![CDATA[
Noise is intrinsic to many important regulatory processes in living cells, and often forms obstacles to be overcome for reliable biological functions. However, due to stochastic birth and death events of all components in biomolecular systems, suppression of noise of one component by another is fundamentally hard and costly. Quantitatively, a widelycited severe lower bound on noise suppression in biomolecular systems was established by Lestas et. al. in 2010, assuming that the plant and the controller have separate birth and death reactions. This makes the precision observed in several biological phenomena, e.g., cell fate decision making and cell cycle time ordering, seem impossible. We demonstrate that coupling, a mechanism widely observed in biology, could suppress noise lower than the bound of Lestas et. al. with moderate energy cost. Furthermore, we systematically investigate the coupling mechanism in all two-node reaction networks, showing that negative feedback suppresses noise better than incoherent feedforward achitectures, coupled systems have less noise than their decoupled version for a large class of networks, and coupling has its own fundamental limitations in noise suppression. Results in this work have implications for noise suppression in biological control and provide insight for a new efficient mechanism of noise suppression in biology.
]]></description>
<dc:creator>Xiao, F.</dc:creator>
<dc:creator>Fang, M.</dc:creator>
<dc:creator>Doyle, J. C.</dc:creator>
<dc:date>2018-10-11</dc:date>
<dc:identifier>doi:10.1101/440453</dc:identifier>
<dc:title><![CDATA[Coupled Reaction Networks for Noise Suppression]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/444620v1?rss=1">
<title>
<![CDATA[
A direct comparison of genome alignment and transcriptome pseudoalignment 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/444620v1?rss=1</link>
<description><![CDATA[
MotivationGenome alignment of reads is the first step of most genome analysis workflows. In the case of RNA-Seq, transcriptome pseudoalignment of reads is a fast alternative to genome alignment, but the different "coordinate systems" of the genome and transcriptome have made it difficult to perform direct comparisons between the approaches.nnResultsWe have developed tools for converting genome alignments to transcriptome pseudoalignments, and conversely, for projecting transcriptome pseudoalignments to genome alignments. Using these tools, we performed a direct comparison of genome alignment with transcriptome pseudoalignment. We find that both approaches produce similar quantifications. This means that for many applications genome alignment and transcriptome pseudoalignment are interchangeable.nnAvailability and Implementationbam2tcc is a C++14 software for converting alignments in SAM/BAM format to transcript compatibility counts (TCCs) and is available at https://github.com/pachterlab/bam2tcc. kallisto genomebam is a user option of kallisto that outputs a sorted BAM file in genome coordinates as part of transcriptome pseudoalignment. The feature has been released with kallisto v0.44.0, and is available at https://pachterlab.github.io/kallisto/.nnSupplementary MaterialN/AnnContactLior Pachter (lpachter@caltech.edu)
]]></description>
<dc:creator>Yi, L.</dc:creator>
<dc:creator>Liu, L.</dc:creator>
<dc:creator>Melsted, P.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2018-10-16</dc:date>
<dc:identifier>doi:10.1101/444620</dc:identifier>
<dc:title><![CDATA[A direct comparison of genome alignment and transcriptome pseudoalignment]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/445312v1?rss=1">
<title>
<![CDATA[
Connectional architecture of a mouse hypothalamic circuit node controlling social behavior 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/445312v1?rss=1</link>
<description><![CDATA[
Type 1 Estrogen receptor-expressing neurons in the ventrolateral subdivision of the ventromedial hypothalamus (VMHvlEsr1) play a causal role in the control of social behaviors including aggression. Here we use six different viral-genetic tracing methods to map the connectional architecture of VMHvlEsr1 neurons. These data reveal a high level of input convergence and output divergence ("fan-in/fan-out") from and to over 30 distinct brain regions, with a high degree (~90%) of recurrence. Unlike GABAergic populations in other hypothalamic nuclei controlling feeding and parenting behavior, VMHvlEsr1 glutamatergic neurons collateralize to multiple targets. However, we identify two anatomically distinct subpopulations with anterior vs. posterior biases in their collateralization patterns. Surprisingly, these two subpopulations receive indistinguishable inputs. These studies suggest an overall system architecture in which an anatomically feed-forward sensory-to-motor processing stream is integrated with a dense, highly recurrent central processing circuit. This architecture differs from the "brain-inspired" feed-forward circuits used in certain types of artificial intelligence networks.nnSIGNIFICANCEHow the cellular heterogeneity of brain nuclei maps onto circuit connectivity, the relationship of this anatomical mapping to behavioral function, and whether there are general principles underlying this relationship, remains poorly understood. Here we systematically map the connectivity of estrogen receptor-1-expressing neurons in the ventromedial hypothalamus (VMHvlEsr1), which control aggression and other social behaviors. We find that a relatively sparse, anatomically feed-forward sensory-to-motor processing stream is integrated with a dense, highly recurrent central processing circuit. Further, the VMHvl contains at least two subpopulations of Esr1+ neurons with different cell body characteristics and locations, with distinct patterns of collateralization to downstream targets. Nevertheless, these projection-defined subpopulations receive similar inputs. This input-output organization appears distinct from those described in other hypothalamic nuclei.
]]></description>
<dc:creator>Lo, L.</dc:creator>
<dc:creator>Kim, D.-W.</dc:creator>
<dc:creator>Yao, S.</dc:creator>
<dc:creator>Cetin, A.</dc:creator>
<dc:creator>Harris, J.</dc:creator>
<dc:creator>Zeng, H.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:creator>Weissbourd, B.</dc:creator>
<dc:date>2018-10-16</dc:date>
<dc:identifier>doi:10.1101/445312</dc:identifier>
<dc:title><![CDATA[Connectional architecture of a mouse hypothalamic circuit node controlling social behavior]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/448449v1?rss=1">
<title>
<![CDATA[
Transduction of the Geomagnetic Field as Evidenced from Alpha-band Activity in the Human Brain 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/448449v1?rss=1</link>
<description><![CDATA[
Magnetoreception, the perception of the geomagnetic field, is a sensory modality well-established across all major groups of vertebrates and some invertebrates, but its presence in humans has been tested rarely, yielding inconclusive results. We report here a strong, specific human brain response to ecologically-relevant rotations of Earth-strength magnetic fields. Following geomagnetic stimulation, a drop in amplitude of EEG alpha oscillations (8-13 Hz) occurred in a repeatable manner. Termed alpha event-related desynchronization (alpha-ERD), such a response is associated with sensory and cognitive processing of external stimuli. Biophysical tests showed that the neural response was sensitive to the dynamic components and axial alignment of the field but also to the static components and polarity of the field. This pattern of results implicates ferromagnetism as the biophysical basis for the sensory transduction and provides a basis to start the behavioral exploration of human magnetoreception.
]]></description>
<dc:creator>Wang, C. X.</dc:creator>
<dc:creator>Hilburn, I. A.</dc:creator>
<dc:creator>Wu, D.-A.</dc:creator>
<dc:creator>Mizuhara, Y.</dc:creator>
<dc:creator>Couste, C. P.</dc:creator>
<dc:creator>Abrams, J. N. H.</dc:creator>
<dc:creator>Bernstein, S. E.</dc:creator>
<dc:creator>Matani, A.</dc:creator>
<dc:creator>Shimojo, S.</dc:creator>
<dc:creator>Kirschvink, J. L.</dc:creator>
<dc:date>2018-10-20</dc:date>
<dc:identifier>doi:10.1101/448449</dc:identifier>
<dc:title><![CDATA[Transduction of the Geomagnetic Field as Evidenced from Alpha-band Activity in the Human Brain]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/453662v1?rss=1">
<title>
<![CDATA[
ETDB-Caltech: a blockchain-based distributed public database for electron tomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/453662v1?rss=1</link>
<description><![CDATA[
Three-dimensional electron microscopy techniques like electron tomography provide valuable insights into cellular structures, and present significant challenges for data storage and dissemination. Here we explored a novel method to publicly release more than 11,000 such datasets, more than 30 TB in total, collected by our group. Our method, based on a peer-to-peer file sharing network built around a blockchain ledger, offers a distributed solution to data storage. In addition, we offer a user-friendly browser-based interface, https://etdb.caltech.edu, for anyone interested to explore and download our data. We discuss the relative advantages and disadvantages of this system and provide tools for other groups to mine our data and/or use the same approach to share their own imaging datasets.
]]></description>
<dc:creator>Ortega, D. R.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>Ding, H. J.</dc:creator>
<dc:creator>Rees-Lee, P.</dc:creator>
<dc:creator>Alexandria,</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2018-10-25</dc:date>
<dc:identifier>doi:10.1101/453662</dc:identifier>
<dc:title><![CDATA[ETDB-Caltech: a blockchain-based distributed public database for electron tomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/453787v1?rss=1">
<title>
<![CDATA[
Visual cue-related activity of cells in the medial entorhinal cortex during navigation in virtual reality 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/453787v1?rss=1</link>
<description><![CDATA[
During spatial navigation, animals use self-motion to estimate positions through path integration. However, estimation errors accumulate over time and it is unclear how they are corrected. Here we report a new cell class ("cue cell") in mouse medial entorhinal cortex (MEC) that encoded visual cue information that could be used to correct errors in path integration. Cue cells accounted for a large fraction of unidentified MEC cells. They exhibited firing fields only near visual cues during virtual navigation and spatially stable activity during navigation in a real arena. Cue cells responses occurred in sequences repeated at each cue and were likely driven by visual inputs. In layers 2/3 of the MEC, cue cells formed clusters. Anatomically adjacent cue cells responded similarly to cues. These cue cell properties demonstrate that the MEC circuits contain a code representing spatial landmarks that could play a significant role in error correction during path integration.
]]></description>
<dc:creator>Kinkhabwala, A.</dc:creator>
<dc:creator>Gu, Y.</dc:creator>
<dc:creator>Aronov, D.</dc:creator>
<dc:creator>Tank, D. W.</dc:creator>
<dc:date>2018-10-25</dc:date>
<dc:identifier>doi:10.1101/453787</dc:identifier>
<dc:title><![CDATA[Visual cue-related activity of cells in the medial entorhinal cortex during navigation in virtual reality]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/454587v1?rss=1">
<title>
<![CDATA[
Rapid Tilt-Series Acquisition for Electron Cryotomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/454587v1?rss=1</link>
<description><![CDATA[
Using a new Titan Krios stage equipped with a single-axis holder, we developed two methods to accelerate the collection of tilt-series. We demonstrate a continuous-tilting method that can record a tilt-series in seconds (about 100x faster than current methods), but with loss of details finer than [~]4 nm. We also demonstrate a fast-incremental method that can record a tilt-series about 10x faster than current methods and with similar resolution. We characterize the utility of both methods in real biological electron cryotomography workflows. We identify opportunities for further improvements in hardware and software and speculate on the impact such advances could have on structural biology.
]]></description>
<dc:creator>Chreifi, G.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Metskas, L. A.</dc:creator>
<dc:creator>Kaplan, M.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2018-10-26</dc:date>
<dc:identifier>doi:10.1101/454587</dc:identifier>
<dc:title><![CDATA[Rapid Tilt-Series Acquisition for Electron Cryotomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/455063v1?rss=1">
<title>
<![CDATA[
Fusion of DARPin to aldolase enables visualization of small protein by cryoEM 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/455063v1?rss=1</link>
<description><![CDATA[
In recent years, solving protein structures by single particle cryogenic electron microscopy (cryoEM) has become a crucial tool in structural biology. While exciting progress is being made towards the visualization of smaller and smaller macromolecules, the median protein size in both eukaryotes and bacteria is still beyond the reach of single particle cryoEM. To overcome this problem, we implemented a platform strategy in which a small protein target was rigidly attached to a large, symmetric base via a selectable adapter. Seven designs were tested. In the best construct, a designed ankyrin repeat protein (DARPin) was rigidly fused to tetrameric rabbit muscle aldolase through a helical linker. The DARPin retained its ability to bind its target, the 27 kDa green fluorescent protein (GFP). We solved the structure of this complex to 3.0 [A] resolution overall, with 5 to 8 [A] resolution in the GFP region. As flexibility in the DARPin limited the overall resolution of the target, we describe strategies to rigidify this element.nnAuthor summarySingle particle cryogenic electron microscopy (cryoEM) is a technique that uses images of purified proteins to determine their atomic structure. Unfortunately, the majority of proteins in the human and bacterial proteomes are too small to be analyzed by cryoEM. Over the years, several groups have suggested the use of a platform to increase the size of small protein targets. The platform is composed of a large protein base and a selectable adapter that binds the target protein. Here we report a platform based on tetrameric rabbit muscle aldolase that is fused to a Designed Ankyrin Repeat Protein (DARPin). Phage display libraries can be used to generate DARPins against target proteins. The residues mutated in a phage display library to generate a DARPin against a new target do not overlap with the DARPin-base fusion in the platform, thus changing the DARPin identity will not disrupt the platform design. The DARPin adapter used here is capable of binding Green Fluorescent Protein (GFP). We report the structure of GFP to 5 to 8 [A] local resolution by single particle cryoEM. Our analysis demonstrates that flexibility in the DARPin-aldolase platform prevents us from achieving higher resolution in the GFP region. We suggest changes to the DARPin design to rigidify the DARPin-aldolase platform. This work expands on current platforms and paves a generally applicable way toward structure determination of small proteins by cryoEM.
]]></description>
<dc:creator>Yao, Q.</dc:creator>
<dc:creator>Weaver, S. J.</dc:creator>
<dc:creator>Mock, J.-Y.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2018-10-30</dc:date>
<dc:identifier>doi:10.1101/455063</dc:identifier>
<dc:title><![CDATA[Fusion of DARPin to aldolase enables visualization of small protein by cryoEM]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/455493v1?rss=1">
<title>
<![CDATA[
Design Guidelines For Sequestration Feedback Networks 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/455493v1?rss=1</link>
<description><![CDATA[
Integral control is commonly used in mechanical and electrical systems to ensure perfect adaptation. A proposed design of integral control for synthetic biological systems employs the sequestration of two biochemical controller species. The unbound amount of controller species captures the integral of the error between the current and the desired state of the system. However, implementing integral control inside bacterial cells using sequestration feedback has been challenging due to the controller molecules being degraded and diluted. Furthermore, integral control can only be achieved under stability conditions that not all sequestration feedback networks fulfill. In this work, we give guidelines for ensuring stability and good performance (small steady-state error) in sequestration feedback networks. Our guidelines provide simple tuning options to obtain a flexible and practical biological implementation of sequestration feedback control. Using tools and metrics from control theory, we pave the path for the systematic design of synthetic biological circuits.
]]></description>
<dc:creator>Baetica, A.-A.</dc:creator>
<dc:creator>Leong, Y. P.</dc:creator>
<dc:creator>Olsman, N.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2018-10-30</dc:date>
<dc:identifier>doi:10.1101/455493</dc:identifier>
<dc:title><![CDATA[Design Guidelines For Sequestration Feedback Networks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/456483v1?rss=1">
<title>
<![CDATA[
Identification of peripheral neural circuits that regulate heart rate using optogenetic and viral vector strategies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/456483v1?rss=1</link>
<description><![CDATA[
Heart rate is under the precise control of the autonomic nervous system. However, the wiring of peripheral neural circuits that regulate heart rate is poorly understood. Here, we developed a clearing-imaging-analysis pipeline to visualize innervation of intact hearts in 3D and employed a multi-technique approach to map parasympathetic and sympathetic neural circuits that control heart rate in mice. We anatomically and functionally identify cholinergic neurons and noradrenergic neurons in an intrinsic cardiac ganglion and the stellate ganglia, respectively, that project to the sinoatrial node. We also report that the heart rate response to optogenetic versus electrical stimulation of the vagus nerve displays different temporal characteristics and that vagal afferents enhance parasympathetic and reduce sympathetic tone to the heart via central mechanisms. Our findings provide new insights into neural regulation of heart rate, and our methodology to study cardiac circuits can be readily used to interrogate neural control of other visceral organs.
]]></description>
<dc:creator>Rajendran, P. S.</dc:creator>
<dc:creator>Challis, R. C.</dc:creator>
<dc:creator>Fowlkes, C. C.</dc:creator>
<dc:creator>Hanna, P.</dc:creator>
<dc:creator>Tompkins, J. D.</dc:creator>
<dc:creator>Jordan, M. C.</dc:creator>
<dc:creator>Hiyari, S.</dc:creator>
<dc:creator>Gabris-Weber, B. A.</dc:creator>
<dc:creator>Greenbaum, A.</dc:creator>
<dc:creator>Chan, K. Y.</dc:creator>
<dc:creator>Deverman, B. E.</dc:creator>
<dc:creator>Munzberg, H.</dc:creator>
<dc:creator>Ardell, J. L.</dc:creator>
<dc:creator>Salama, G.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:creator>Shivkumar, K.</dc:creator>
<dc:date>2018-10-29</dc:date>
<dc:identifier>doi:10.1101/456483</dc:identifier>
<dc:title><![CDATA[Identification of peripheral neural circuits that regulate heart rate using optogenetic and viral vector strategies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/462036v1?rss=1">
<title>
<![CDATA[
A new family of neural wiring receptors across bilaterians defined by phylogenetic, biochemical and structural evidence 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/462036v1?rss=1</link>
<description><![CDATA[
The evolution of complex nervous systems was accompanied by the expansion of groups of protein families, most notably cell adhesion molecules, surface receptors and their ligands. These proteins mediate axonal guidance, synapse targeting, and other neuronal wiring-related functions. Recently, members of a set of thirty interacting cell surface proteins belonging to two newly defined families of the immunoglobulin superfamily (IgSF) in fruit flies were discovered to label different subsets of neurons in the brain and ventral nerve cord. They have been shown to be involved in synaptic targeting and morphogenesis, retrograde signaling, and neuronal survival. Here we show that these proteins, denoted as Dprs and DIPs, belong to a family of two and three-Ig domain molecules in bilaterians generally known for neuronal wiring functions. In protostomes, the ancestral Dpr/DIP gene has duplicated to form heterophilic partners, such as Dprs and DIPs, while in deuterostomes, they have evolved to create the IgLON family of neuronal receptors. In support of this phylogeny, we show that IgLONs interact with each other, and that their complexes can be broken by mutations designed using homology models based on Dpr and DIP structures. Similarly, the nematode orthologs ZIG-8 and RIG-5 can form heterophilic and homophilic complexes structurally matching Dpr-DIP and DIP-DIP complexes. The evolutionary, biochemical and structural relationships we demonstrate here provides insights into neural development and the rise of complexity in metazoans.nnSignificance StatementCell surface receptors assign and display unique identities to neurons, and direct proper and robust wiring of neurons to create functional neural circuits. Recent work has identified two new classes of receptors in fruit flies, called the Dpr and DIP families with 30 members, which interact in 38 pairwise combinations. These proteins are implicated in neural identity, wiring and survival in many parts of the fly nervous system. Here, using evolutionary, biochemical and structural evidence, we show that Dprs and DIPs are members of an ancient bilaterian family of receptors. Members of this family share functional roles relevant to wiring across species, and are likely crucial in the emergence of the bilaterian nervous systems common to vertebrate and invertebrate animals.
]]></description>
<dc:creator>Cheng, S.</dc:creator>
<dc:creator>Park, Y.</dc:creator>
<dc:creator>Kurleto, J. D.</dc:creator>
<dc:creator>Jeon, M.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:creator>Thornton, J. W.</dc:creator>
<dc:creator>Özkan, E.</dc:creator>
<dc:date>2018-11-05</dc:date>
<dc:identifier>doi:10.1101/462036</dc:identifier>
<dc:title><![CDATA[A new family of neural wiring receptors across bilaterians defined by phylogenetic, biochemical and structural evidence]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-11-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/464800v1?rss=1">
<title>
<![CDATA[
Occupancy patterns of 208 DNA-associated proteins in a single human cell type 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/464800v1?rss=1</link>
<description><![CDATA[
Genome-wide occupancy maps of transcriptional regulators are important for understanding gene regulation and its effects on diverse biological processes, but only a small fraction of the >1,600 transcription factors (TFs) encoded in the human genome has been assayed. Here we present data and analyses of ChIP-seq experiments for 208 DNA-associated proteins (DAPs) in the HepG2 hepatocellular carcinoma line, spanning nearly a quarter of its expressed TFs, transcriptional co-factors, and chromatin regulator proteins. The DAP binding profiles classify into major groups associated predominantly with promoters or enhancers, or with both. We confirm and expand the current catalog of DNA sequence motifs; 77 factors showed similar motifs to those previously described using in vivo and/or in vitro methods, and 17 yielded novel motifs. We also describe motifs corresponding to other TFs that co-enrich with the primary ChIP target. FOX family motifs are, for example, significantly enriched in ChIP-seq peaks of 37 other DAPs. We show that promoters and enhancers can be discriminated based on motif content and occupancy patterns. This large catalog reveals High Occupancy Target (HOT) regions at which many DAPs associate, although each contains motifs for only a minority of the numerous associated DAPs. These analyses provide a deeper and more complete overview of the gene regulatory networks that define this cell type.
]]></description>
<dc:creator>Partridge, E. C.</dc:creator>
<dc:creator>Chhetri, S. B.</dc:creator>
<dc:creator>Prokop, J. W.</dc:creator>
<dc:creator>Ramaker, R. C.</dc:creator>
<dc:creator>Jansen, C. S.</dc:creator>
<dc:creator>Goh, S.-T.</dc:creator>
<dc:creator>Mackiewicz, M.</dc:creator>
<dc:creator>Newberry, K. M.</dc:creator>
<dc:creator>Brandsmeier, L. A.</dc:creator>
<dc:creator>Meadows, S. K.</dc:creator>
<dc:creator>Messer, C. L.</dc:creator>
<dc:creator>Hardigan, A. A.</dc:creator>
<dc:creator>Dean, E. C.</dc:creator>
<dc:creator>Jiang, S.</dc:creator>
<dc:creator>Savic, D.</dc:creator>
<dc:creator>Mortazavi, A.</dc:creator>
<dc:creator>Wold, B. J.</dc:creator>
<dc:creator>Myers, R. M.</dc:creator>
<dc:creator>Mendenhall, E. M.</dc:creator>
<dc:date>2018-11-07</dc:date>
<dc:identifier>doi:10.1101/464800</dc:identifier>
<dc:title><![CDATA[Occupancy patterns of 208 DNA-associated proteins in a single human cell type]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-11-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/465658v1?rss=1">
<title>
<![CDATA[
Oxytocin effects on the resting-state mentalizing brain network 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/465658v1?rss=1</link>
<description><![CDATA[
Oxytocin(OT) has effects in both human behavior and in the brain, which is not limited in the specific brain area but also with the potential effect on connectivity with other brain regions. Evidence indicate that the effects of OT on human behavior are multifaceted, such as trust behavior, decrease anxiety, empathy and bonding behavior. Since the vital role of mentalizing in understanding others, here we proposed and tested that whether OT has a general effect on theory of mind brain network which is associated to the effect of related social behavioral and personality traits. Used a randomized, double-blind placebo-controlled group design, we investigated the resting-state functional magnetic resonance imaging after intranasal OT or placebo. The functional connectivity (FC) maps with seed in left temporoparietal junction (lTPJ) and right TPJ showed that OT significantly increased connectivity between rTPJ and default attention network (DAN), while decreased the FC between lTPJ and medial prefrontal network (MPN). With implementing machine learning approach, we further reported satisfactory classification accuracy that Identified altered FCs of TPJ can classify OT and PL group. Moreover, individuals empathy trait can modulate the FC between left TPJ and right RECT, which was positively correlated with empathic concern in PL group whereas lTPJ-rRECT negatively correlated in OT group. These results demonstrate that OT has significant effect on FC with lTPJ and rTPJ, brain regions critical for mentalizing, and the empathy concern can modulate the FC. These findings add to our understanding of the neural mechanisms by which OT modulates social behaviors, especially in social interaction involving mentalizing.
]]></description>
<dc:creator>Wu, H.</dc:creator>
<dc:creator>Feng, C.</dc:creator>
<dc:creator>Lu, X.</dc:creator>
<dc:creator>Liu, X.</dc:creator>
<dc:creator>Liu, Q.</dc:creator>
<dc:date>2018-11-08</dc:date>
<dc:identifier>doi:10.1101/465658</dc:identifier>
<dc:title><![CDATA[Oxytocin effects on the resting-state mentalizing brain network]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-11-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/467878v1?rss=1">
<title>
<![CDATA[
Mouse Academy: high-throughput automated training and trial-by-trial behavioral analysis during learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/467878v1?rss=1</link>
<description><![CDATA[
Progress in understanding how individual animals learn will require high-throughput standardized methods for behavioral training but also advances in the analysis of the resulting behavioral data. In the course of training with multiple trials, an animal may change its behavior abruptly, and capturing such events calls for a trial-by-trial analysis of the animals strategy. To address this challenge, we developed an integrated platform for automated animal training and analysis of behavioral data. A low-cost and space-efficient apparatus serves to train entire cohorts of mice on a decision-making task under identical conditions. A generalized linear model (GLM) analyzes each animals performance at single-trial resolution. This model infers the momentary decision-making strategy and can predict the animals choice on each trial with an accuracy of ~80%. We also assess the animals detailed trajectories and body poses within the apparatus. Unsupervised analysis of these features revealed unusual trajectories that represent hesitation in the response. This integrated hardware/software platform promises to accelerate the understanding of animal learning.
]]></description>
<dc:creator>Qiao, M.</dc:creator>
<dc:creator>Zhang, T.</dc:creator>
<dc:creator>Segalin, C.</dc:creator>
<dc:creator>Sam, S.</dc:creator>
<dc:creator>Perona, P.</dc:creator>
<dc:creator>Meister, M.</dc:creator>
<dc:date>2018-11-16</dc:date>
<dc:identifier>doi:10.1101/467878</dc:identifier>
<dc:title><![CDATA[Mouse Academy: high-throughput automated training and trial-by-trial behavioral analysis during learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-11-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/472571v1?rss=1">
<title>
<![CDATA[
The Barcode, UMI, Set format and BUStools 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/472571v1?rss=1</link>
<description><![CDATA[
We introduce the Barcode-UMI-Set format (BUS) for representing pseudoalignments of reads from single-cell RNA-seq experiments. The format can be used with all single-cell RNA-seq technologies, and we show that BUS files can be efficiently generated. BUStools is a suite of tools for working with BUS files and facilitates rapid quantification and analysis of single-cell RNA-seq data. The BUS format therefore makes possible the development of modular, technology-specific, and robust workflows for single-cell RNA-seq analysis.
]]></description>
<dc:creator>Melsted, P.</dc:creator>
<dc:creator>Ntranos, V.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2018-11-18</dc:date>
<dc:identifier>doi:10.1101/472571</dc:identifier>
<dc:title><![CDATA[The Barcode, UMI, Set format and BUStools]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-11-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/472811v1?rss=1">
<title>
<![CDATA[
Cooperation Enhances Robustness of Coexistence in Spatially Structured Consortia 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/472811v1?rss=1</link>
<description><![CDATA[
Designing synthetic microbial consortia is an emerging area in synthetic biology and a major goal is to realize stable and robust coexistence of multiple species. Co-operation and competition are fundamental intra/interspecies interactions that shape population level behaviors, yet it is not well-understood how these interactions affect the stability and robustness of coexistence. In this paper, we show that communities with cooperative interactions are more robust to population disturbance, e.g., depletion by antibiotics, by forming intermixed spatial patterns. Meanwhile, competition leads to population spatial heterogeneity and more fragile coexistence in communities. Using reaction-diffusion and nonlocal PDE models and simulations of a two-species E. coli consortium, we demonstrate that cooperation is more beneficial than competition in maintaining coexistence in spatially structured consortia, but not in well-mixed environments. This also suggests a trade-off between constructing heterogeneous communities with localized functions and maintaining robust coexistence. The results provide general strategies for engineering spatially structured consortia by designing interspecies interactions and suggest the importance of cooperation for biodiversity in microbial community.
]]></description>
<dc:creator>Ren, X.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2018-11-19</dc:date>
<dc:identifier>doi:10.1101/472811</dc:identifier>
<dc:title><![CDATA[Cooperation Enhances Robustness of Coexistence in Spatially Structured Consortia]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-11-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/475525v1?rss=1">
<title>
<![CDATA[
Refinement of metabolite detection in cystic fibrosis sputum reveals heme negatively correlates with lung function 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/475525v1?rss=1</link>
<description><![CDATA[
Pseudomonas aeruginosa lung infections are a leading cause of morbidity and mortality in cystic fibrosis (CF) patients (1, 2). Our laboratory has studied a class of small molecules produced by P. aeruginosa known as phenazines, including pyocyanin and its biogenic precursor phenazine-1-carboxylic acid (PCA). As phenazines are known virulence factors (3), we and others have explored the possibility of using phenazine concentrations as a marker for disease progression (4-6). Previously, we reported that sputum concentrations of pyocyanin and PCA negatively correlate with lung function in cystic fibrosis patients (6). Our study used high performance liquid chromatography (HPLC) to quantify phenazines by UV-vis absorbance after extraction from lung sputum. Since our initial study, methods for metabolite analysis have advanced considerably, aided in large part by usage of mass spectrometry (LC-MS) and tandem mass spectrometry (LC-MS/MS). Because a more recent study employing LC-MS/MS revealed a surprising decoupling of P. aeruginosa metabolites in sputum and the detection of P. aeruginosa through culturing or microbiome profiles (4), we decided to check whether we could reproduce our previous findings by analyzing sputum samples from a different patient cohort with a new LC-MS instrument in our laboratory. Our new samples were provided by the Mountain West CF Consortium Sputum Biomarker study (7). In the course of performing our new analyses, comparison of our old HPLC data to our new LC-MS data led us to realize that the peak previously assigned to PCA instead originates from heme, and the peak assigned to pyocyanin originates from an as-yet unknown compound. This correction only affects the measurements of phenazines in sputum, and we are confident in the phenazine measurements from isolated cultures and the 16S rRNA gene sequencing data from that study (6). Here we outline the basis for our correction and present additional data showing that heme concentration negatively correlates with lung function in cystic fibrosis patients.
]]></description>
<dc:creator>Glasser, N. R.</dc:creator>
<dc:creator>Hunter, R. C.</dc:creator>
<dc:creator>Liou, T. G.</dc:creator>
<dc:creator>Newman, D. K. K.</dc:creator>
<dc:creator>Mountain West CF Consortium Investigators,</dc:creator>
<dc:date>2018-11-23</dc:date>
<dc:identifier>doi:10.1101/475525</dc:identifier>
<dc:title><![CDATA[Refinement of metabolite detection in cystic fibrosis sputum reveals heme negatively correlates with lung function]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-11-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/482331v1?rss=1">
<title>
<![CDATA[
Modular, part-based control of gene expression response time using protein degradation tags 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/482331v1?rss=1</link>
<description><![CDATA[
A fundamental principle of cellular signal processing is the encoding of information within the temporal dynamics of regulatory circuits. If synthetic circuits are to achieve the versatility and effectiveness of naturally-occurring circuits, it is necessary to develop simple, effective methods for the control of the dynamical properties of genetic circuits. However, current approaches to dynamical control often require extensive rewiring of circuit architecture, which hinders their implementation in a variety of systems. Therefore, it is essential that simple, modular, genetic parts-based frameworks are created to control the dynamical properties of circuits. Here we address this need by implementing a modular, genetic parts-based system which tunes the response time of a genes expression by tuning its degradation rate via the application of protein degradation tags with various affinities to their protease. This system provides a simple, easily- applicable framework for controlling the temporal aspects of genetic circuit behavior.
]]></description>
<dc:creator>Jones, E. M.</dc:creator>
<dc:creator>Monette, C. E.</dc:creator>
<dc:creator>Marken, J. P.</dc:creator>
<dc:creator>Dhawan, S.</dc:creator>
<dc:creator>Gibney, T.</dc:creator>
<dc:creator>Li, C.</dc:creator>
<dc:creator>Liu, W.</dc:creator>
<dc:creator>Luz-Ricca, A.</dc:creator>
<dc:creator>Ren, X.</dc:creator>
<dc:creator>Zheng, X.</dc:creator>
<dc:creator>Saha, M.</dc:creator>
<dc:date>2018-11-29</dc:date>
<dc:identifier>doi:10.1101/482331</dc:identifier>
<dc:title><![CDATA[Modular, part-based control of gene expression response time using protein degradation tags]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-11-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/490920v1?rss=1">
<title>
<![CDATA[
High-molecular-weight polymers from dietary fiber drive aggregation of particulates in the murine small intestine 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/490920v1?rss=1</link>
<description><![CDATA[
The lumen of the small intestine (SI) is filled with particulates: microbes, therapeutic particles, and food granules. The structure of this particulate suspension could impact uptake of drugs and nutrients and the function of microorganisms; however, little is understood about how this suspension is re-structured as it transits the gut. Here, we demonstrate that particles spontaneously aggregate in SI luminal fluid ex vivo. We find that mucins and immunoglobulins are not required for aggregation. Instead, aggregation can be controlled using polymers from dietary fiber in a manner that is qualitatively consistent with polymer-induced depletion interactions, which do not require specific chemical interactions. Furthermore, we find that aggregation is tunable; by feeding mice dietary fibers of different molecular weights, we can control aggregation in SI luminal fluid. This work suggests that the molecular weight and concentration of dietary polymers play an underappreciated role in shaping the physicochemical environment of the gut.
]]></description>
<dc:creator>Preska Steinberg, A.</dc:creator>
<dc:creator>Datta, S. S.</dc:creator>
<dc:creator>Naragon, T.</dc:creator>
<dc:creator>Rolando, J. C.</dc:creator>
<dc:creator>Bogatyrev, S. R.</dc:creator>
<dc:creator>Ismagilov, R. F.</dc:creator>
<dc:date>2018-12-10</dc:date>
<dc:identifier>doi:10.1101/490920</dc:identifier>
<dc:title><![CDATA[High-molecular-weight polymers from dietary fiber drive aggregation of particulates in the murine small intestine]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-12-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/492918v1?rss=1">
<title>
<![CDATA[
Dynamics of microRNA expression during mouse prenatal development 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/492918v1?rss=1</link>
<description><![CDATA[
MicroRNAs (miRNAs) play a critical role as post-transcriptional regulators of gene expression. The ENCODE project profiled the expression of miRNAs in a comprehensive set of tissues during a time-course of mouse embryonic development and captured the expression dynamics of 785 miRNAs. We found distinct tissue and developmental stage specific miRNA expression clusters, with an overall pattern of increasing tissue specific expression as development proceeds. Comparative analysis of conserved miRNAs in mouse and human revealed stronger clustering of expression patterns by tissue types rather than by species. An analysis of messenger RNA gene expression clusters compared with miRNA expression clusters identifies the potential role of specific miRNA expression clusters in suppressing the expression of mRNAs specific to other developmental programs in the tissue where these microRNAs are expressed during embryonic development. Our results provide the most comprehensive timecourse of miRNA expression as an integrated part of the ENCODE reference dataset for mouse embryonic development.
]]></description>
<dc:creator>Murad, R.</dc:creator>
<dc:creator>Rahmanian, S.</dc:creator>
<dc:creator>Breschi, A.</dc:creator>
<dc:creator>Zeng, W.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>Mackiewicz, M.</dc:creator>
<dc:creator>Roberts, B.</dc:creator>
<dc:creator>Meadows, S.</dc:creator>
<dc:creator>Moore, D.</dc:creator>
<dc:creator>Davis, C.</dc:creator>
<dc:creator>Trout, D.</dc:creator>
<dc:creator>Zaleski, C.</dc:creator>
<dc:creator>Dobin, A.</dc:creator>
<dc:creator>Sei, L.-H.</dc:creator>
<dc:creator>Drenkow, J.</dc:creator>
<dc:creator>Scavelli, A.</dc:creator>
<dc:creator>Gingeras, T. R.</dc:creator>
<dc:creator>Wold, B.</dc:creator>
<dc:creator>Myers, R. M.</dc:creator>
<dc:creator>Guigo, R.</dc:creator>
<dc:creator>Mortazavi, A.</dc:creator>
<dc:date>2018-12-10</dc:date>
<dc:identifier>doi:10.1101/492918</dc:identifier>
<dc:title><![CDATA[Dynamics of microRNA expression during mouse prenatal development]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-12-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/508226v1?rss=1">
<title>
<![CDATA[
Combinatorial Control through Allostery 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/508226v1?rss=1</link>
<description><![CDATA[
Many instances of cellular signaling and transcriptional regulation involve switch-like molecular responses to the presence or absence of input ligands. To understand how these responses come about and how they can be harnessed, we develop a statistical mechanical model to characterize the types of Boolean logic that can arise from allosteric molecules following the Monod-Wyman-Changeux (MWC) model. Building upon previous work, we show how an allosteric molecule regulated by two inputs can elicit AND, OR, NAND and NOR responses, but is unable to realize XOR or XNOR gates. Next, we demonstrate the ability of an MWC molecule to perform ratiometric sensing - a response behavior where activity depends monotonically on the ratio of ligand concentrations. We then extend our analysis to more general schemes of combinatorial control involving either additional binding sites for the two ligands or an additional third ligand and show how these additions can cause a switch in the logic behavior of the molecule. Overall, our results demonstrate the wide variety of control schemes that biological systems can implement using simple mechanisms.
]]></description>
<dc:creator>Galstyan, V.</dc:creator>
<dc:creator>Funk, L.</dc:creator>
<dc:creator>Einav, T.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2018-12-31</dc:date>
<dc:identifier>doi:10.1101/508226</dc:identifier>
<dc:title><![CDATA[Combinatorial Control through Allostery]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-12-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/512996v1?rss=1">
<title>
<![CDATA[
Visual-olfactory integration in the human disease vector mosquito, Aedes aegypti 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/512996v1?rss=1</link>
<description><![CDATA[
Mosquitoes rely on the integration of multiple sensory cues, including olfactory, visual, and thermal stimuli, to detect, identify and locate their hosts [1-4]. Although we increasingly know more about the role of chemosensory behaviours in mediating mosquito-host interactions [1], the role of visual cues remains comparatively less studied [3], and how the combination of olfactory and visual information is integrated in the mosquito brain remains unknown. In the present study, we used a tethered-flight LED arena, which allowed for quantitative control over the stimuli, to show that CO2 exposure affects target-tracking responses, but not responses to large-field visual stimuli. In addition, we show that CO2 modulates behavioural responses to visual objects in a time-dependent manner. To gain insight into the neural basis of this olfactory and visual coupling, we conducted two-photon microscopy experiments in a new GCaMP6s-expressing mosquito line. Imaging revealed that the majority of ROIs in the lobula region of the optic lobe exhibited strong responses to small-field stimuli, but showed little response to a large-field stimulus. Approximately 20% of the neurons we imaged were modulated when an attractive odour preceded the visual stimulus; these same neurons also elicited a small response when the odour was presented alone. By contrast, imaging in the antennal lobe revealed no modulation when visual stimuli were presented before or after the olfactory stimulus. Together, our results are the first to reveal the dynamics of olfactory modulation in visually evoked behaviours of mosquitoes, and suggest that coupling between these sensory systems is asymmetrical and time-dependent.
]]></description>
<dc:creator>Vinauger, C.</dc:creator>
<dc:creator>Van Breugel, F.</dc:creator>
<dc:creator>Locke, L.</dc:creator>
<dc:creator>Tobin, K.</dc:creator>
<dc:creator>Dickinson, M.</dc:creator>
<dc:creator>Fairhall, A.</dc:creator>
<dc:creator>Akbari, O.</dc:creator>
<dc:creator>Riffell, J.</dc:creator>
<dc:date>2019-01-07</dc:date>
<dc:identifier>doi:10.1101/512996</dc:identifier>
<dc:title><![CDATA[Visual-olfactory integration in the human disease vector mosquito, Aedes aegypti]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/517573v1?rss=1">
<title>
<![CDATA[
The client-binding domain of the cochaperone SGTA/Sgt2 has a helical-hand structure that binds a short hydrophobic helix 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/517573v1?rss=1</link>
<description><![CDATA[
The targeting and insertion of tail-anchored (TA) integral membrane proteins (IMP) into the correct membrane is critical for cellular homeostasis. The fungal protein Sgt2, and its human homolog SGTA, binds hydrophobic clients and is the entry point for targeting of ER-bound TA IMPs. Here we reveal molecular details that underlie the mechanism of Sgt2 binding to TA IMP clients. We establish that the Sgt2 C-terminal region is flexible but conserved and sufficient for client binding. A molecular model for this domain reveals a helical hand forming a hydrophobic groove, consistent with a higher affinity for TA IMP clients with hydrophobic faces and a minimal length of 11 residues. This work places Sgt2 into a broader family of TPR-containing co-chaperone proteins.
]]></description>
<dc:creator>Lin, K.-F.</dc:creator>
<dc:creator>Fry, M. Y.</dc:creator>
<dc:creator>Saladi, S.</dc:creator>
<dc:creator>Clemons, W. M.</dc:creator>
<dc:date>2019-01-10</dc:date>
<dc:identifier>doi:10.1101/517573</dc:identifier>
<dc:title><![CDATA[The client-binding domain of the cochaperone SGTA/Sgt2 has a helical-hand structure that binds a short hydrophobic helix]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/517839v1?rss=1">
<title>
<![CDATA[
Cancer Classification from Healthy DNA using Machine Learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/517839v1?rss=1</link>
<description><![CDATA[
The genome is traditionally viewed as a time-independent source of information; a paradigm that drives researchers to seek correlations between the presence of certain genes and a patients risk of disease. This analysis neglects genomic temporal changes, which we believe to be a crucial signal for predicting an individuals susceptibility to cancer. We hypothesize that each individuals genome passes through an evolution channel (The term channel is motivated by the notion of communication channel introduced by Shannon1 in 1948 and started the area of Information Theory), that is controlled by hereditary, environmental and stochastic factors. This channel differs among individuals, giving rise to varying predispositions to developing cancer. We introduce the concept of mutation profiles that are computed without any comparative analysis, but by analyzing the short tandem repeat regions in a single healthy genome and capturing information about the individuals evolution channel. Using machine learning on data from more than 5,000 TCGA cancer patients, we demonstrate that these mutation profiles can accurately distinguish between patients with various types of cancer. For example, the pairwise validation accuracy of the classifier between PAAD (pancreas) patients and GBM (brain) patients is 93%. Our results show that healthy unaffected cells still contain a cancer-specific signal, which opens the possibility of cancer prediction from a healthy genome.
]]></description>
<dc:creator>Jain, S.</dc:creator>
<dc:creator>Mazaheri, B.</dc:creator>
<dc:creator>Raviv, N.</dc:creator>
<dc:creator>Bruck, J.</dc:creator>
<dc:date>2019-01-11</dc:date>
<dc:identifier>doi:10.1101/517839</dc:identifier>
<dc:title><![CDATA[Cancer Classification from Healthy DNA using Machine Learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/518878v1?rss=1">
<title>
<![CDATA[
Short Tandem Repeats Information in TCGA is Statistically Biased by Amplification 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/518878v1?rss=1</link>
<description><![CDATA[
The current paradigm in data science is based on the belief that given sufficient amounts of data, classifiers are likely to uncover the distinction between true and false hypotheses. In particular, the abundance of genomic data creates opportunities for discovering disease risk associations and help in screening and treatment. However, working with large amounts of data is statistically beneficial only if the data is statistically unbiased. Here we demonstrate that amplification methods of DNA samples in TCGA have a substantial effect on short tandem repeat (STR) information. In particular, we design a classifier that uses the STR information and can distinguish between samples that have an analyte code D and an analyte code W. This artificial bias might be detrimental to data driven approaches, and might undermine the conclusions based on past and future genome wide studies.
]]></description>
<dc:creator>Jain, S.</dc:creator>
<dc:creator>Mazaheri, B.</dc:creator>
<dc:creator>Raviv, N.</dc:creator>
<dc:creator>Bruck, J.</dc:creator>
<dc:date>2019-01-11</dc:date>
<dc:identifier>doi:10.1101/518878</dc:identifier>
<dc:title><![CDATA[Short Tandem Repeats Information in TCGA is Statistically Biased by Amplification]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/521096v1?rss=1">
<title>
<![CDATA[
Design principles for open source bioinstrumentation: the poseidon syringe pump system as an example 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/521096v1?rss=1</link>
<description><![CDATA[
The poseidon syringe pump and microscope system is an open source alternative to commercial systems. It costs less than $400 and can be assembled in under an hour using the instructions and source files available at https://pachterlab.github.io/poseidon. We describe the poseidon system and use it to illustrate design principles that can facilitate the adoption and development of open source bioinstruments. The principles are functionality, robustness, simplicity, modularity, benchmarking, and documentation.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>da Veiga Beltrame, E.</dc:creator>
<dc:creator>Bannon, D.</dc:creator>
<dc:creator>Gehring, J.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2019-01-17</dc:date>
<dc:identifier>doi:10.1101/521096</dc:identifier>
<dc:title><![CDATA[Design principles for open source bioinstrumentation: the poseidon syringe pump system as an example]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/525063v1?rss=1">
<title>
<![CDATA[
In vivo structure of the Legionella type II secretion system by electron cryotomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/525063v1?rss=1</link>
<description><![CDATA[
The type II secretion system (T2SS) is a multi-protein envelope-spanning assembly that translocates a wide range of virulence factors, enzymes and effectors through the outer membrane (OM) of many Gram-negative bacteria. Here, using electron cryotomography and subtomogram averaging methods, we present the first in situ structure of an intact T2SS, imaged within the human pathogen Legionella pneumophila. Although the T2SS has only limited sequence and component homology with the evolutionarily-related Type IV pilus (T4P) system, we show that their overall architectures are remarkably similar. Despite similarities, there are also differences, including for instance that the T2SS-ATPase complex is usually present but disengaged from the inner membrane, the T2SS has a much longer periplasmic vestibule, and it has a short-lived flexible pseudopilus. Placing atomic models of the components into our ECT map produced a complete architectural model of the intact T2SS that provides new insights into the structure and function of its components, its position within the cell envelope, and the interactions between its different subcomplexes. Overall, these structural results strongly support the piston model for substrate extrusion.
]]></description>
<dc:creator>Ghosal, D.</dc:creator>
<dc:creator>Kim, K. W.</dc:creator>
<dc:creator>Zheng, H.</dc:creator>
<dc:creator>Kaplan, M.</dc:creator>
<dc:creator>Vogel, J. P.</dc:creator>
<dc:creator>Cianciotto, N. P.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2019-01-19</dc:date>
<dc:identifier>doi:10.1101/525063</dc:identifier>
<dc:title><![CDATA[In vivo structure of the Legionella type II secretion system by electron cryotomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/525857v1?rss=1">
<title>
<![CDATA[
Conditional Guide RNAs: Programmable Conditional Regulation of CRISPR/Cas Function in Bacteria via Dynamic RNA Nanotechnology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/525857v1?rss=1</link>
<description><![CDATA[
A guide RNA (gRNA) directs the function of a CRISPR protein effector to a target gene of choice, providing a versatile programmable platform for engineering diverse modes of synthetic regulation (edit, silence, induce, bind). However, the fact that gRNAs are constitutively active places limitations on the ability to confine gRNA activity to a desired location and time. To achieve programmable control over the scope of gRNA activity, here we apply principles from dynamic RNA nanotechnology to engineer conditional guide RNAs (cgRNAs) whose activity is dependent on the presence or absence of an RNA trigger. These cgRNAs are programmable at two levels, with the trigger-binding sequence controlling the scope of the effector activity and the target-binding sequence determining the subject of the effector activity. We demonstrate molecular mechanisms for both constitutively active cgRNAs that are conditionally inactivated by an RNA trigger (ON[-&gt;]OFF logic) and constitutively inactive cgRNAs that are conditionally activated by an RNA trigger (OFF[-&gt;]ON logic). For each mechanism, automated sequence design is performed using the reaction pathway designer within NUPACK to design an orthogonal library of three cgRNAs that respond to different RNA triggers. In E. coli expressing cgRNAs, triggers, and silencing dCas9 as the protein effector, we observe programmable conditional gene silencing with a median dynamic range of {approx}6-fold for an ON[-&gt;]OFF "terminator switch" mechanism, {approx}15-fold for an ON[-&gt;]OFF "splinted switch" mechanism, and {approx}3.6-fold for an OFF[-&gt;]ON "toehold switch" mechanism; the median crosstalk within each cgRNA library is <2%, <2%, and {approx}20% for the three mechanisms. By providing programmable control over both the scope and target of protein effector function, cgRNA regulators offer a promising platform for synthetic biology.nnO_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY
]]></description>
<dc:creator>Hanewich-Hollatz, M. H.</dc:creator>
<dc:creator>Chen, Z.</dc:creator>
<dc:creator>Huang, J.</dc:creator>
<dc:creator>Hochrein, L. M.</dc:creator>
<dc:creator>Pierce, N. A.</dc:creator>
<dc:date>2019-01-21</dc:date>
<dc:identifier>doi:10.1101/525857</dc:identifier>
<dc:title><![CDATA[Conditional Guide RNAs: Programmable Conditional Regulation of CRISPR/Cas Function in Bacteria via Dynamic RNA Nanotechnology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/526426v1?rss=1">
<title>
<![CDATA[
Multi-Cell ECM compaction is predictable via superposition of nonlinear cell dynamics linearized in augmented state space 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/526426v1?rss=1</link>
<description><![CDATA[
Cells interacting through an extracellular matrix (ECM) exhibit emergent behaviors resulting from collective intercellular interaction. In wound healing and tissue development, characteristic compaction of ECM gel is induced by multiple cells that generate tensions in the ECM fibers and coordinate their actions with other cells. Computational prediction of collective cell-ECM interaction based on first principles is highly complex especially as the number of cells increase. Here, we introduce a computationally-efficient method for predicting nonlinear behaviors of multiple cells interacting mechanically through a 3-D ECM fiber network. The key enabling technique is superposition of single cell computational models to predict multicellular behaviors. While cell-ECM interactions are highly nonlinear, they can be linearized accurately with a unique method, termed Dual-Faceted Linearization. This method recasts the original nonlinear dynamics in an augmented space where the system behaves more linearly. The independent state variables are augmented by combining auxiliary variables that inform nonlinear elements involved in the system. This computational method involves a) expressing the original nonlinear state equations with two sets of linear dynamic equations b) reducing the order of the augmented linear system via principal component analysis and c) superposing individual single cell-ECM dynamics to predict collective behaviors of multiple cells. The method is computationally efficient compared to original nonlinear dynamic simulation and accurate compared to traditional Taylor expansion linearization. Furthermore, we reproduce reported experimental results of multi-cell induced ECM compaction.nnAuthor summaryCollective behaviors of multiple cells interacting through an ECM are prohibitively complex to predict with a mechanistic computational model due to its highly nonlinear dynamics and high dimensional space. We introduce a methodology where nonlinear dynamics of single cells are superposed to predict collective multi-cellular behaviors through a developed linearization method. We represent nonlinear single cell dynamics with linear state equations by augmenting the independent state variables with a set of auxiliary variables. We then transform the linear augmented state equations to a low-dimensional latent model and superpose the linear latent models of individual cells to predict collective behaviors that emerge from multi-cellular interactions. The method successfully reproduced experimental results of cell-induced ECM compaction.
]]></description>
<dc:creator>Mayalu, M. N.</dc:creator>
<dc:creator>Kim, M.</dc:creator>
<dc:creator>Asada, H. H.</dc:creator>
<dc:date>2019-01-21</dc:date>
<dc:identifier>doi:10.1101/526426</dc:identifier>
<dc:title><![CDATA[Multi-Cell ECM compaction is predictable via superposition of nonlinear cell dynamics linearized in augmented state space]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/531582v1?rss=1">
<title>
<![CDATA[
Phototrophic Methane Oxidation in a Member of the Chloroflexi Phylum 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/531582v1?rss=1</link>
<description><![CDATA[
Biological methane cycling plays an important role in Earths climate and the global carbon cycle, with biological methane oxidation (methanotrophy) modulating methane release from numerous environments including soils, sediments, and water columns. Methanotrophy is typically coupled to aerobic respiration or anaerobically via the reduction of sulfate, nitrate, or metal oxides, and while the possibility of coupling methane oxidation to phototrophy (photomethanotrophy) has been proposed, no organism has ever been described that is capable of this metabolism. Here we described a new bacterial genome from a member of the Chloroflexi phylum--termed here Candidatus Chlorolinea photomethanotrophicum--with cooccurring methanotrophy and phototrophy pathways, suggesting a novel link between these two metabolisms. Recovered as a metagenome-assembled genome from microbial mats in an iron-rich hot spring in Japan, Ca.  C. photomethanotrophicum forms a new lineage within the Chloroflexi phylum and expands the known metabolic diversity of this already diverse clade. Ca.  C. photomethanotrophicum appears to be metabolically versatile, capable of phototrophy (via a Type 2 reaction center), aerobic respiration, nitrite reduction, oxidation of methane and carbon monoxide, and potentially carbon fixation via a novel pathway composed of hybridized components of the serine cycle and the 3-hydroxypropionate bicycle. The biochemical network of this organism is constructed from components from multiple organisms and pathways, further demonstrating the modular nature of metabolic machinery and the ecological and evolutionary importance of horizontal gene transfer in the establishment of novel pathways.

SignificanceMethane is a major greenhouse gas, and the production and consumption of methane is largely driven by the metabolism of microorganisms. Although it has been hypothesized for decades that some bacteria may be capable of growth by eating methane and conserving energy from sunlight (photomethanotrophy), this metabolism has never been discovered in nature. Here, we describe the first genetic evidence for a bacterium capable of photomethanotrophy, adding a new pathway to the known diversity of how microbes can make a living. This discovery also adds a new link to the global carbon cycle, and may provide new opportunities for designing biotechnological tools for processing methane.
]]></description>
<dc:creator>Ward, L.</dc:creator>
<dc:creator>Shih, P. M.</dc:creator>
<dc:creator>Hemp, J.</dc:creator>
<dc:creator>Kakegawa, T.</dc:creator>
<dc:creator>Fischer, W. W.</dc:creator>
<dc:creator>McGlynn, S. E.</dc:creator>
<dc:date>2019-01-26</dc:date>
<dc:identifier>doi:10.1101/531582</dc:identifier>
<dc:title><![CDATA[Phototrophic Methane Oxidation in a Member of the Chloroflexi Phylum]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/533091v1?rss=1">
<title>
<![CDATA[
The SUMO ligase Su(var)2-10 links piRNA-guided target recognition to chromatin silencing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/533091v1?rss=1</link>
<description><![CDATA[
Regulation of transcription is the main mechanism responsible for precise control of gene expression. While the majority of transcriptional regulation is mediated by a multitude of DNA-binding transcription factors that bind to regulatory gene regions, an elegant alternative strategy employs small RNA guides, piwi-interacting RNAs (piRNAs) to identify targets of transcriptional repression. Here we show that in Drosophila the small ubiquitin-like protein SUMO and the SUMO E3 ligase Su(var)2-10 are required for piRNA-guided deposition of repressive chromatin marks and transcriptional silencing of piRNA targets. Su(var)2-10 links the piRNA-guided target recognition complex to the silencing effector by binding the piRNA/Piwi complex and inducing SUMO-dependent recruitment of the SetDB1/Wde histone methyltransferase effector. We propose that in Drosophila, the nuclear piRNA pathway has co-opted a conserved mechanism of SUMO-dependent recruitment of the SetDB1/Wde chromatin modifier to confer repression of genomic parasites.

Highlights- piRNA-induced transposon silencing requires SUMO and the SUMO E3 ligase Su(var)2-10
- Su(var)2-10 links the target recognition complex to the silencing effector
- Su(var)2-10 binds the piRNA-guided target recognition complex and deposits SUMO on target chromatin
- Su(var)2-10 induces SUMO-dependent recruitment of the SetDB1/Wde histone methyltransferase to target loci
]]></description>
<dc:creator>Ninova, M.</dc:creator>
<dc:creator>Chen, Y.-C. A.</dc:creator>
<dc:creator>Godneeva, B.</dc:creator>
<dc:creator>Rogers, A. K.</dc:creator>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>Aravin, A. A.</dc:creator>
<dc:creator>Fejes Toth, K.</dc:creator>
<dc:date>2019-01-29</dc:date>
<dc:identifier>doi:10.1101/533091</dc:identifier>
<dc:title><![CDATA[The SUMO ligase Su(var)2-10 links piRNA-guided target recognition to chromatin silencing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/533232v1?rss=1">
<title>
<![CDATA[
The SUMO ligase Su(var)2-10 controls eu- and heterochromatic gene expression via establishment of H3K9 trimethylation and negative feedback regulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/533232v1?rss=1</link>
<description><![CDATA[
Chromatin is critical for genome compaction and gene expression. On a coarse scale, the genome is divided into euchromatin, which harbors the majority of genes and is enriched in active chromatin marks, and heterochromatin, which is gene-poor but repeat-rich. The conserved molecular hallmark of heterochromatin is the H3K9me3 modification, which is associated with gene silencing. We found that in Drosophila deposition of most of the H3K9me3 mark depends on SUMO and the SUMO-ligase Su(var)2-10, which recruits the histone methyltransferase complex SetDB1/Wde. In addition to repressing repeats, H3K9me3 also influences expression of both hetero- and euchromatic host genes. High H3K9me3 levels in heterochromatin are required to suppress spurious non-canonical transcription and ensure proper gene expression. In euchromatin, a set of conserved genes is repressed by Su(var)2-10/SetDB1-induced H3K9 trimethylation ensuring tissue-specific gene expression. Several components of heterochromatin are themselves repressed by this pathway providing a negative feedback mechanism to ensure chromatin homeostasis.

Highlights- Proper expression of host genes residing in heterochromatin requires Su(var)2-10-dependent installation of the H3K9me3 mark to suppress spurious non-canonical transcription.
- A set of euchromatic host genes is repressed by transposon-independent installation of H3K9me3 in a process that depends on Su(var)2-10 and SUMO.
- Installation of H3K9me3 via Su(var)2-10 ensures tissue-specific gene expression.
- H3K9me3-dependent silencing of genes encoding proteins involved in heterochromatin formation provides negative feedback regulation to maintain heterochromatin homeostasis.
]]></description>
<dc:creator>Ninova, M.</dc:creator>
<dc:creator>Godneeva, B.</dc:creator>
<dc:creator>Chen, Y.-C. A.</dc:creator>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>Prakash, S. J.</dc:creator>
<dc:creator>Jankovics, F.</dc:creator>
<dc:creator>Erdelyi, M.</dc:creator>
<dc:creator>Fejes Toth, K.</dc:creator>
<dc:creator>Aravin, A. A.</dc:creator>
<dc:date>2019-01-29</dc:date>
<dc:identifier>doi:10.1101/533232</dc:identifier>
<dc:title><![CDATA[The SUMO ligase Su(var)2-10 controls eu- and heterochromatic gene expression via establishment of H3K9 trimethylation and negative feedback regulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/536268v1?rss=1">
<title>
<![CDATA[
A novel mesocosm set-up reveals strong methane emission reduction in submerged peat moss Sphagnum cuspidatum by tightly associated methanotrophs. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/536268v1?rss=1</link>
<description><![CDATA[
Wetlands present the largest natural sources of methane (CH4) and their potential CH4 emissions greatly vary due to the activity of CH4-oxidizing bacteria associated with wetland plant species. In this study, the association of CH4-oxidizing bacteria with submerged Sphagnum peat mosses was studied, followed by the development of a novel mesocosm set-up. This set-up enabled the precise control of CH4 input and allowed for monitoring the dissolved CH4 in a Sphagnum moss layer while mimicking natural conditions. Two mesocosm set-ups were used in parallel: one containing a Sphagnum moss layer in peat water, and a control only containing peat water. Moss-associated CH4 oxidizers in the field could reduce net CH4 emission up to 93%, and in the mesocosm set-up up to 31%. Furthermore, CH4 oxidation was only associated with Sphagnum, and did not occur in peat water. Especially methanotrophs containing a soluble methane monooxygenase enzyme were significantly enriched during the 32 day mesocosm incubations. Together these findings showed the new mesocosm setup is very suited to study CH4 cycling in submerged Sphagnum moss community under controlled conditions. Furthermore, the tight associated between Sphagnum peat mosses and methanotrophs can significantly reduce CH4 emissions in submerged peatlands.
]]></description>
<dc:creator>Kox, M. A. R.</dc:creator>
<dc:creator>Smolders, A. J. P.</dc:creator>
<dc:creator>Speth, D. R.</dc:creator>
<dc:creator>Lamers, L. P. M.</dc:creator>
<dc:creator>Op den Camp, H. J. M.</dc:creator>
<dc:creator>Jetten, M. S. M.</dc:creator>
<dc:creator>Van Kessel, M. A. H. J.</dc:creator>
<dc:date>2019-01-31</dc:date>
<dc:identifier>doi:10.1101/536268</dc:identifier>
<dc:title><![CDATA[A novel mesocosm set-up reveals strong methane emission reduction in submerged peat moss Sphagnum cuspidatum by tightly associated methanotrophs.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/547265v1?rss=1">
<title>
<![CDATA[
96 Eyes: Parallel Fourier Ptychographic Microscopy for high throughput screening 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/547265v1?rss=1</link>
<description><![CDATA[
We report the implementation of a parallel microscopy system (96 Eyes) that is capable of simultaneous imaging of all wells on a 96-well plate. The optical system consists of 96 microscopy units, where each unit is made out of a four element objective, made through a molded injection process, and a low cost CMOS camera chip. By illuminating the sample with angle varying light and applying Fourier Ptychography, we can improve the effective brightfield imaging numerical apertuure of the objectives from 0.23 to 0.3, and extend the depth of field from {+/-}5 m to {+/-}15 m. The use of Fourier Ptychography additionally allows us to computationally correct the objectives aberrations out of the rendered images, and provides us with the ability to render phase images. The 96 Eyes acquires raw data at a rate of 0.7 frame per second (all wells) and the data are processed with 4 cores of graphical processing units (GPUs; GK210, Nvidia Tesla K80, USA). The system is also capable of fluorescence imaging (excitation = 465 nm, emission = 510 nm) at the native resolution of the objectives. We demonstrate the capability of this system by imaging S1P1-eGFP-Human bone osteosarcoma epithelial (U2OS) cells.
]]></description>
<dc:creator>Chan, A. C. S.</dc:creator>
<dc:creator>Kim, J.</dc:creator>
<dc:creator>Pan, A.</dc:creator>
<dc:creator>Xu, H.</dc:creator>
<dc:creator>Nojima, D.</dc:creator>
<dc:creator>Hale, C.</dc:creator>
<dc:creator>Wang, S.</dc:creator>
<dc:creator>Yang, C.</dc:creator>
<dc:date>2019-02-13</dc:date>
<dc:identifier>doi:10.1101/547265</dc:identifier>
<dc:title><![CDATA[96 Eyes: Parallel Fourier Ptychographic Microscopy for high throughput screening]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-02-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/552018v1?rss=1">
<title>
<![CDATA[
Electrophysiology and transcriptomics reveal two photoreceptor classes and complex visual integration in Hirudo verbana 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/552018v1?rss=1</link>
<description><![CDATA[
Among animals with complex visual processing mechanisms, the leech Hirudo verbana is a rare example in which all neurons can be identified. However, little is known about its visual system, which is composed of several pigmented head eyes and photosensitive non-pigmented sensilla that are distributed across its entire body. Although several interneurons are known to respond to visual stimuli, their response properties are poorly understood. Among these, the S cell system is especially intriguing: It is multimodal, spans the entire body of the leech, and is thought to be involved in complex sensory integration. To improve our understanding of the role of this system, we tested its spectral sensitivity, spatial integration, and adaptation properties. The response of the S cell system to visual stimuli was found to be strongly dependent on the size of the area stimulated, and adaptation was local. Furthermore, a "bleaching experiment" demonstrated that at least two color channels contributed to the response, and that their contribution was dependent on the adaptation to the background. The existence of at least two color channels was further supported by transcriptomic evidence, which indicated the existence of at least two distinct groups of putative opsins for leeches. Taken together, our results show that the S cell system has highly sophisticated response properties, and could be involved in the processing of complex visual stimuli. We propose the leech as a novel system to understand visual processing mechanisms with many practical advantages.

Summary statementDetailed quantitative analysis of light responses in the medicinal leech Hirudo verbana unequivocally demonstrates the existence of parallel visual pathways processing visual and UV stimuli. Responses to spatially complex stimuli indicate relatively sophisticated information processing.
]]></description>
<dc:creator>Stowasser, A.</dc:creator>
<dc:creator>Stahl, A.</dc:creator>
<dc:creator>Benoit, J. B.</dc:creator>
<dc:creator>Wagenaar, D. A.</dc:creator>
<dc:date>2019-02-15</dc:date>
<dc:identifier>doi:10.1101/552018</dc:identifier>
<dc:title><![CDATA[Electrophysiology and transcriptomics reveal two photoreceptor classes and complex visual integration in Hirudo verbana]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-02-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/553271v1?rss=1">
<title>
<![CDATA[
RecV recombinase system for spatiotemporally controlled light-inducible genomic modifications. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/553271v1?rss=1</link>
<description><![CDATA[
Brain circuits are composed of vast numbers of intricately interconnected neurons with diverse molecular, anatomical and physiological properties. To allow highly specific targeting of individual neurons for structural and functional studies, we modified three site-specific DNA recombinases, Cre, Dre and Flp, by combining them with a fungal light-inducible protein, Vivid, so that their recombinase activities can be driven by blue light. We generated viral vectors to express these light-inducible recombinases and demonstrated that they can induce genomic modifications in dense or sparse populations of neurons in live mouse brains controlled by one-photon or two-photon light induction. As an important application, we showed that light-inducible recombinases can produce highly targeted, sparse and strong labeling of individual neurons thereby enabling whole-brain morphological reconstruction to identify their axonal projection specificity. In addition to targeting cortical brain areas, we applied the method in deep targets, with a demonstration of functional calcium imaging. These molecular tools enable spatiotemporally-precise, targeted genomic modifications that will greatly facilitate detailed analysis of neural circuits and linking genetic identity, morphology, connectivity and function.
]]></description>
<dc:creator>Cetin, A. H.</dc:creator>
<dc:creator>Yao, S.</dc:creator>
<dc:creator>Ouellette, B.</dc:creator>
<dc:creator>Balaram, P.</dc:creator>
<dc:creator>Zhou, T.</dc:creator>
<dc:creator>Mortrud, M.</dc:creator>
<dc:creator>Chatterjee, S.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Daigle, T. L.</dc:creator>
<dc:creator>Tasic, B.</dc:creator>
<dc:creator>Kuang, X.</dc:creator>
<dc:creator>Gong, H.</dc:creator>
<dc:creator>Luo, Q.</dc:creator>
<dc:creator>Zeng, S.</dc:creator>
<dc:creator>Kahan, A.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:creator>Zeng, H.</dc:creator>
<dc:date>2019-02-18</dc:date>
<dc:identifier>doi:10.1101/553271</dc:identifier>
<dc:title><![CDATA[RecV recombinase system for spatiotemporally controlled light-inducible genomic modifications.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-02-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/558684v1?rss=1">
<title>
<![CDATA[
Programmable DNA cleavage by Ago nucleases from mesophilic bacteria Clostridium butyricum and Limnothrix rosea 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/558684v1?rss=1</link>
<description><![CDATA[
Argonaute (Ago) proteins are the key players in RNA interference in eukaryotes, where they function as RNA-guided RNA endonucleases. Prokaryotic Argonautes (pAgos) are much more diverse than their eukaryotic counterparts but their cellular functions and mechanisms of action remain largely unknown. Some pAgos were shown to use small DNA guides for endonucleolytic cleave of complementary DNA in vitro. However, previously studied pAgos from thermophilic prokaryotes function at elevated temperatures which limits their potential use as a tool in genomic applications. Here, we describe two pAgos from mesophilic bacteria, Clostridium butyricum (CbAgo) and Limnothrix rosea (LrAgo), that act as DNA-guided DNA nucleases at physiological temperatures. In contrast to previously studied pAgos, CbAgo and LrAgo can use not only 5-phosphorylated but also 5-hydroxyl DNA guides, with diminished precision of target cleavage. Both LrAgo and CbAgo can tolerate guide/target mismatches in the seed region, but are sensitive to mismatches in the 3-guide region. CbAgo is highly active under a wide range of conditions and can be used for programmable endonucleolytic cleavage of both single-stranded and double-stranded DNA substrates at moderate temperatures. The biochemical characterization of mesophilic pAgo proteins paths the way for their use for DNA manipulations both in vitro and in vivo.
]]></description>
<dc:creator>Kuzmenko, A.</dc:creator>
<dc:creator>Yudin, D.</dc:creator>
<dc:creator>Ryazansky, S.</dc:creator>
<dc:creator>Kulbachinskiy, A.</dc:creator>
<dc:creator>Aravin, A.</dc:creator>
<dc:date>2019-02-22</dc:date>
<dc:identifier>doi:10.1101/558684</dc:identifier>
<dc:title><![CDATA[Programmable DNA cleavage by Ago nucleases from mesophilic bacteria Clostridium butyricum and Limnothrix rosea]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-02-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/559104v1?rss=1">
<title>
<![CDATA[
Persistence of neuronal representations through time and damage in the hippocampus. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/559104v1?rss=1</link>
<description><![CDATA[
Memories can persist for decades but how they are stably encoded in individual and groups of neurons is not known. To investigate how a familiar environment is encoded in CA1 neurons over time we implanted bilateral microendoscopes in transgenic mice to image the activity of pyramidal neurons in the hippocampus over weeks. Most of the neurons (90 %) are active every day, however, the response of neurons to specific cues changes across days. Approximately 40 % of place and time cells lose fields between two days; however, on timescales longer than two days the neuronal pattern changes at a rate of 1 % for each additional day. Despite continuous changes, field responses are more resilient, with place/time cells recovering their fields after a 10-day period of no task or following CA1 damage. Recovery of these neuronal patterns is characterized by transient changes in firing fields which ultimately converge to the original representation. Unlike individual neurons, groups of neurons with inter and intrahemispheric synchronous activity form stable place and time fields across days. Neurons whose activity was synchronous with a large group of neurons were more likely to preserve their responses to place or time across multiple days. These results support the view that although task-relevant information stored in individual neurons is relatively labile, it can persist in networks of neurons with synchronized activity spanning both hemispheres.

One Sentence SummaryNeuronal representations in networks of neurons with synchronized activity are stable over weeks, even after lack of training or following damage.
]]></description>
<dc:creator>Gonzalez, W. G.</dc:creator>
<dc:creator>Zhang, H.</dc:creator>
<dc:creator>Harutyunyan, A.</dc:creator>
<dc:creator>Lois, C.</dc:creator>
<dc:date>2019-02-24</dc:date>
<dc:identifier>doi:10.1101/559104</dc:identifier>
<dc:title><![CDATA[Persistence of neuronal representations through time and damage in the hippocampus.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-02-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/564955v1?rss=1">
<title>
<![CDATA[
Compositional Data Analysis is necessary for simulating and analyzing RNA-Seq data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/564955v1?rss=1</link>
<description><![CDATA[
*Seq techniques (e.g. RNA-Seq) generate compositional datasets, i.e. the number of fragments sequenced is not proportional to the samples total RNA content. Thus, datasets carry only relative information, even though absolute RNA copy numbers are of interest. Current normalization methods assume most features do not change, which can lead to misleading conclusions when there are many changes. Furthermore, there are few real datasets and no simulation protocols currently available that can directly benchmark methods when many changes occur.

We present absSimSeq, an R package that simulates compositional data in the form of RNA-Seq reads. We compared absSimSeq with several existing tools used for RNA-Seq differential analysis: sleuth, DESeq2, edgeR, limma, sleuth and ALDEx2 (which explicitly takes a compositional approach). We compared the standard normalization of these tools to either "compositional normalization", which uses log-ratios to anchor the data on a set of negative control features, or RUVSeq, another tool that directly uses negative control features.

Our analysis shows that common normalizations result in reduced performance with current methods when there is a large change in the total RNA per cell. Performance improves when spike-ins are included and used with a compositional approach, even if the spike-ins have substantial variation. In contrast, RUVSeq, which normalizes count data rather than compositional data, has poor performance. Further, we show that previous criticisms of spike-ins did not take into consideration the compositional nature of the data. We demonstrate that absSimSeq can generate more representative datasets for testing performance, and that spike-ins should be more frequently used in a compositional manner to minimize misleading conclusions in differential analyses.

Author SummaryA critical question in biomedical research is "Is there any change in the RNA transcript abundance when cellular conditions change?" RNA Sequencing (RNA-Seq) is a powerful tool that can help answer this question, but two critical parts of obtaining accurate measurements are (A) understanding the kind of data that RNA-Seq produces, and (B) "normalizing" the data between samples to allow for a fair comparison. Most tools assume that RNA-Seq data is count data, but in reality it is "compositional" data, meaning only percentages/proportions are available, which cannot directly answer the critical question. This leads to distorted results when attempting to simulate or analyze data that has a large global change.

To address this problem, we designed a new simulation protocol called absSimSeq that can more accurately represent RNA-Seq data when there are large changes. We also proposed a "compositional normalization" method that can utilize "negative control" features that are known to not change between conditions to anchor the data. When there are many features changing, this approach improves performance over commonly used normalization methods across multiple tools. This work highlights the importance of having negative controls features available and of treating RNA-Seq data as compositional.
]]></description>
<dc:creator>McGee, W. A.</dc:creator>
<dc:creator>Pimentel, H.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Wu, J. Y.</dc:creator>
<dc:date>2019-03-02</dc:date>
<dc:identifier>doi:10.1101/564955</dc:identifier>
<dc:title><![CDATA[Compositional Data Analysis is necessary for simulating and analyzing RNA-Seq data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/571448v1?rss=1">
<title>
<![CDATA[
An atlas of anterior hox gene expression in the embryonic sea lamprey head: hox-code evolution in vertebrates 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/571448v1?rss=1</link>
<description><![CDATA[
In the hindbrain and the adjacent cranial neural crest (NC) cells of jawed vertebrates (gnathostomes), nested and segmentally-restricted domains of Hox gene expression provide a combinatorial Hox-code for specifying regional properties during head development. Extant jawless vertebrates, such as the sea lamprey (Petromyzon marinus), can provide insights into the evolution and diversification of this Hox-code in vertebrates. There is evidence for gnathostome-like spatial patterns of Hox expression in lamprey; however, the expression domains of the majority of lamprey hox genes from paralogy groups (PG) 1-4 are yet to be characterized, so it is unknown whether they are coupled to hindbrain segments (rhombomeres) and NC. In this study, we systematically describe the spatiotemporal expression of all 14 sea lamprey hox genes from PG1-PG4 in the developing hindbrain and pharynx to investigate the extent to which their expression conforms to the archetypal gnathostome hindbrain and pharyngeal hox-codes. We find many similarities in Hox expression between lamprey and gnathostome species, particularly in rhombomeric domains during hindbrain segmentation and in the cranial neural crest, enabling inference of aspects of Hox expression in the ancestral vertebrate embryonic head. These data are consistent with the idea that a Hox regulatory network underlying hindbrain segmentation is a pan vertebrate trait. We also reveal differences in hindbrain domains at later stages, as well as expression in the endostyle and in pharyngeal arch (PA) 1 mesoderm. Our analysis suggests that many Hox expression domains that are observed in extant gnathostomes were present in ancestral vertebrates but have been partitioned differently across Hox clusters in gnathostome and cyclostome lineages after duplication.
]]></description>
<dc:creator>Parker, H. J.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>Krumlauf, R.</dc:creator>
<dc:date>2019-03-09</dc:date>
<dc:identifier>doi:10.1101/571448</dc:identifier>
<dc:title><![CDATA[An atlas of anterior hox gene expression in the embryonic sea lamprey head: hox-code evolution in vertebrates]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/574608v1?rss=1">
<title>
<![CDATA[
T Cell Receptor Immunotherapy Drives Human Immunodeficiency Virus Evolution in Humanized Mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/574608v1?rss=1</link>
<description><![CDATA[
T cell receptor mediated immunotherapy using engineered Hematopoietic Stem/Progenitor Cells leads to durable partial suppression of HIV in humanized mice. Sustained viral suppression is accompanied by viral evolution under selection pressure. This study highlights the potential for TCR immunotherapy and the need to target multiple epitopes.nnAbstractEffective CD8+ T cell responses targeted to the KK10 epitope of HIV presented by HLA-B*27:05, a protective HLA allele, correlate with the ability to control infection without antiretroviral therapy (ART). Here, we report an immunotherapy approach using two B*27:05-KK10-specific T Cell Receptors (TCRs) isolated from HIV controllers. Immunocompromised mice engrafted with human Hematopoietic Stem/Progenitor Cells (HSPCs) encoding for the TCRs showed differentiation into functionally active engineered T cells. Following infection with HIV, both TCRs showed sustained, albeit modest, viral suppression over 32 weeks, accompanied by a concomitant increase in CD4+ T cells. Sequencing of viral quasi-species from the plasma of infected mice demonstrated clear evidence for viral evolution under selection pressure from the TCRs. The most commonly observed mutation in the KK10 epitope was L6M, which preserved viral fitness but showed attenuated recognition by the TCRs. These studies show that TCR-immunotherapy was able to suppress HIV infection long-term while driving HIV evolution in humanized mice.
]]></description>
<dc:creator>Joglekar, A. V.</dc:creator>
<dc:creator>Swift, M.</dc:creator>
<dc:creator>Leonard, M. T.</dc:creator>
<dc:creator>Jeppson, J. D.</dc:creator>
<dc:creator>Sandoval, S.</dc:creator>
<dc:creator>Baltimore, D.</dc:creator>
<dc:date>2019-03-12</dc:date>
<dc:identifier>doi:10.1101/574608</dc:identifier>
<dc:title><![CDATA[T Cell Receptor Immunotherapy Drives Human Immunodeficiency Virus Evolution in Humanized Mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/575712v1?rss=1">
<title>
<![CDATA[
A multi-state model of the CaMKII dodecamer suggests a role for calmodulin in maintenance of autophosphorylation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/575712v1?rss=1</link>
<description><![CDATA[
Ca2+/calmodulin-dependent protein kinase II (CaMKII) accounts for up to 2 percent of all brain protein and is essential to memory function. CaMKII activity is known to regulate dynamic shifts in the size and signaling strength of neuronal connections, a process known as synaptic plasticity. Increasingly, computational models are used to explore synaptic plasticity and the mechanisms regulating CaMKII activity. Conventional modeling approaches may exclude biophysical detail due to the impractical number of state combinations that arise when explicitly monitoring the conformational changes, ligand binding, and phosphorylation events that occur on each of the CaMKII holoenzymes twelve subunits. To manage the combinatorial explosion without necessitating bias or loss in biological accuracy, we use a specialized syntax in the software MCell to create a rule-based model of the twelve-subunit CaMKII holoenzyme. Here we validate the rule-based model against previous measures of CaMKII activity and investigate molecular mechanisms of CaMKII regulation. Specifically, we explore how Ca2+/CaM-binding may both stabilize CaMKII subunit activation and regulate maintenance of CaMKII autophosphorylation. Noting that Ca2+/CaM and protein phosphatases bind CaMKII at nearby or overlapping sites, we compare model scenarios in which Ca2+/CaM and protein phosphatase do or do not structurally exclude each others binding to CaMKII. Our results suggest a functional mechanism for the so-called "CaM trapping" phenomenon, such that Ca2+/CaM structurally excludes phosphatase binding and thereby prolongs CaMKII autophosphorylation. We conclude that structural protection of autophosphorylated CaMKII by Ca2+/CaM may be an important mechanism for regulation of synaptic plasticity.nnAuthor summaryIn the hippocampus, the dynamic fluctuation in size and strength of neuronal connections is thought to underlie learning and memory processes. These fluctuations, called synaptic plasticity, are in-part regulated by the protein calcium/calmodulin-dependent kinase II (CaMKII). During synaptic plasticity, CaMKII becomes activated in the presence of calcium ions (Ca2+) and calmodulin (CaM), allowing it to interact enzymatically with downstream binding partners. Interestingly, activated CaMKII can phosphorylate itself, resulting in state changes that allow CaMKII to be functionally active independent of Ca2+/CaM. Phosphorylation of CaMKII at Thr-286/287 has been shown to be a critical component of learning and memory. To explore the molecular mechanisms that regulate the activity of CaMKII holoenzymes, we use a rule-based approach that reduces computational complexity normally associated with representing the wide variety of functional states that a CaMKII holoenzyme can adopt. Using this approach we observe regulatory mechanisms that might be obscured by reductive approaches. Our results newly suggest that CaMKII phosphorylation at Thr-286/287 is stabilized by a mechanism in which CaM structurally excludes phosphatase binding at that site.
]]></description>
<dc:creator>Pharris, M. C.</dc:creator>
<dc:creator>Bartol, T. M.</dc:creator>
<dc:creator>Sejnowski, T. J.</dc:creator>
<dc:creator>Kennedy, M. B.</dc:creator>
<dc:creator>Stefan, M. I.</dc:creator>
<dc:creator>Kinzer-Ursem, T. L.</dc:creator>
<dc:date>2019-03-12</dc:date>
<dc:identifier>doi:10.1101/575712</dc:identifier>
<dc:title><![CDATA[A multi-state model of the CaMKII dodecamer suggests a role for calmodulin in maintenance of autophosphorylation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/580647v1?rss=1">
<title>
<![CDATA[
Ultrasound Imaging of Gene Expression in Mammalian Cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/580647v1?rss=1</link>
<description><![CDATA[
The study of cellular processes occurring inside intact organisms and the development of cell-based diagnostic and therapeutic agents requires methods to visualize cellular functions such as gene expression in deep tissues. Ultrasound is a widely used biomedical technology enabling deep-tissue imaging with high spatial and temporal resolution. However, no genetically encoded molecular reporters are available to connect ultrasound contrast to gene expression in mammalian cells. To address this limitation, we introduce the first mammalian acoustic reporter genes. Starting with an eleven-gene polycistronic gene cluster derived from bacteria, we engineered a eukaryotic genetic program whose introduction into mammalian cells results in the expression of a unique class of intracellular air-filled protein nanostructures called gas vesicles. The scattering of ultrasound by these nanostructures allows mammalian cells to be visualized at volumetric densities below 0.5%, enables the monitoring of dynamic circuit-driven gene expression, and permits high-resolution imaging of gene expression in living animals. These mammalian acoustic reporter genes enable previously impossible approaches to monitoring the location, viability and function of mammalian cells in vivo.
]]></description>
<dc:creator>Farhadi, A.</dc:creator>
<dc:creator>Ho, G. H.</dc:creator>
<dc:creator>Sawyer, D. P.</dc:creator>
<dc:creator>Bourdeau, R. W.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2019-03-18</dc:date>
<dc:identifier>doi:10.1101/580647</dc:identifier>
<dc:title><![CDATA[Ultrasound Imaging of Gene Expression in Mammalian Cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/584292v1?rss=1">
<title>
<![CDATA[
Identification of histological features to predict MUC2 expression in colon cancer tissues 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/584292v1?rss=1</link>
<description><![CDATA[
Colorectal cancer (CRC) is the third-most common form of cancer among Americans. Like normal colon tissue, CRC cells are sustained by a subpopulation of "stem cells" that possess the ability to self-renew and differentiate into more specialized cancer cell types. In normal colon tissue, the enterocytes, goblet cells and other epithelial cells in the mucosa region have distinct morphologies that distinguish them from the other cells in the lamina propria, muscularis mucosa, and submucosa. However, in a tumor, the morphology of the cancer cells varies dramatically. Cancer cells that express genes specific to goblet cells significantly differ in shape and size compared to their normal counterparts. Even though a large number of hematoxylin and eosin (H&E)-stained sections and the corresponding RNA sequencing (RNASeq) data from CRC are available from The Cancer Genome Atlas (TCGA), prediction of gene expression patterns from tissue histological features has not been attempted yet. In this manuscript, we identified histological features that are strongly associated with MUC2 expression patterns in a tumor. Specifically, we show that large nuclear area is associated with MUC2-high tumors (p < 0.001). This discovery provides insight into cancer biology and tumor histology and demonstrates that it may be possible to predict certain gene expressions from histological features.
]]></description>
<dc:creator>Periyakoil, P. K.</dc:creator>
<dc:creator>Clarke, M.</dc:creator>
<dc:creator>Sahoo, D.</dc:creator>
<dc:date>2019-03-21</dc:date>
<dc:identifier>doi:10.1101/584292</dc:identifier>
<dc:title><![CDATA[Identification of histological features to predict MUC2 expression in colon cancer tissues]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/584805v1?rss=1">
<title>
<![CDATA[
Lineage does not regulate the connectivity of projection neurons in the mouse olfactory bulb 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/584805v1?rss=1</link>
<description><![CDATA[
Lineage regulates the synaptic connections between neurons in some regions of the invertebrate nervous system. In mammals recent experiments suggest that cell lineage determines the connectivity of pyramidal neurons in the neocortex, but the functional relevance of this phenomenon and whether it occurs in other neuronal types remains controversial. We investigated whether lineage plays a role in the connectivity of mitral and tufted cells, the projection neurons in the mouse olfactory bulb. We used transgenic mice to label neuronal progenitors sparsely and observed that clonally related neurons receive synaptic input from olfactory sensory neurons expressing different olfactory receptors. These results indicate that lineage does not determine the connectivity between olfactory sensory neurons and olfactory bulb projection neurons.
]]></description>
<dc:creator>Lois, C.</dc:creator>
<dc:creator>Sanchez-Guardado, L.</dc:creator>
<dc:date>2019-03-21</dc:date>
<dc:identifier>doi:10.1101/584805</dc:identifier>
<dc:title><![CDATA[Lineage does not regulate the connectivity of projection neurons in the mouse olfactory bulb]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/588699v1?rss=1">
<title>
<![CDATA[
Hippocampal-midbrain circuit enhances the pleasure of anticipation in the prefrontal cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/588699v1?rss=1</link>
<description><![CDATA[
Having something to look forward to is a keystone of well-being. Anticipation of a future reward, like an upcoming vacation, can often be more gratifying than the very experience itself. Theories of anticipation have described how it induces behaviors ranging from beneficial information-seeking through to harmful addiction. However, it remains unclear how neural systems compute an attractive value from anticipation, instead of from the reward itself. To address this gap, we administered a decision-making task to human participants that allowed us to analyze brain activity during receipt of information predictive of future pleasant outcomes. Using a computational model of anticipatory value that captures participants decisions, we show that an anticipatory value signal is orchestrated by influences from three brain regions. Ventromedial prefrontal cortex (vmPFC) tracks the value of anticipation; dopaminergic midbrain responds to information that enhances anticipation, while sustained hippocampal activity provides a functional coupling between these regions. This coordinating function of the hippocampus is consistent with its known role in episodic future thinking. Our findings shed new light on the neural underpinnings of anticipations influence over decision-making, while also unifying a range of phenomena associated with risk and time-delay preference.
]]></description>
<dc:creator>Iigaya, K.</dc:creator>
<dc:creator>Hauser, T. U.</dc:creator>
<dc:creator>Kurth-Nelson, Z.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:creator>Dayan, P.</dc:creator>
<dc:creator>Dolan, R. J.</dc:creator>
<dc:date>2019-03-26</dc:date>
<dc:identifier>doi:10.1101/588699</dc:identifier>
<dc:title><![CDATA[Hippocampal-midbrain circuit enhances the pleasure of anticipation in the prefrontal cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/591552v1?rss=1">
<title>
<![CDATA[
Addressable, \"Packet-Based\" Intercellular Communication through Plasmid Conjugation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/591552v1?rss=1</link>
<description><![CDATA[
We develop a system for implementing "packet-based" intercellular communication in an engineered bacterial population via conjugation. Our system uses gRNA-based identification markers that allow messages to be addressed to specific strains via Cas9-mediated cleavage of messages sent to the wrong recipient, which we show reduces plasmid transfer by four orders of magnitude. Integrase-mediated editing of the address on the message plasmid allows cells to dynamically update the messages recipients in vivo. As a proof-of-concept demonstration of our system, we propose a linear path scheme that would propagate a message sequentially through the strains of a population in a defined order.
]]></description>
<dc:creator>Marken, J. P.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2019-03-27</dc:date>
<dc:identifier>doi:10.1101/591552</dc:identifier>
<dc:title><![CDATA[Addressable, \"Packet-Based\" Intercellular Communication through Plasmid Conjugation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/591818v1?rss=1">
<title>
<![CDATA[
Changepoint detection versus reinforcement learning: Separable neural substrates approximate different forms of Bayesian inference 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/591818v1?rss=1</link>
<description><![CDATA[
Adaptive behavior in even the simplest decision-making tasks requires predicting future events in an environment that is generally nonstationary. As an inductive problem, this prediction requires a commitment to the statistical process underlying environmental change. This challenge can be formalized in a Bayesian framework as a question of choosing a generative model for the task dynamics. Previous learning models assume, implicitly or explicitly, that nonstationarity follows either a continuous diffusion process or a discrete changepoint process. Each approach is slow to adapt when its assumptions are violated. A new mixture of Bayesian experts framework proposes separable brain systems approximating inference under different assumptions regarding the statistical structure of the environment. This model explains data from a laboratory foraging task, in which rats experienced a change in reward contingencies after pharmacological disruption of dorsolateral (DLS) or dorsomedial striatum (DMS). The data and model suggest DLS learns under a diffusion prior whereas DMS learns under a changepoint prior. The combination of these two systems offers a new explanation for how the brain handles inference in an uncertain environment.nnOne Sentence SummaryAdaptive foraging behavior can be explained by separable brain systems approximating Bayesian inference under different assumptions about dynamics of the environment.
]]></description>
<dc:creator>Pauli, W. M.</dc:creator>
<dc:creator>Jones, M.</dc:creator>
<dc:date>2019-03-28</dc:date>
<dc:identifier>doi:10.1101/591818</dc:identifier>
<dc:title><![CDATA[Changepoint detection versus reinforcement learning: Separable neural substrates approximate different forms of Bayesian inference]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/592808v1?rss=1">
<title>
<![CDATA[
FIND: Identifying Functionally and Structurally Important Features in Protein Sequences with Deep Neural Networks 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/592808v1?rss=1</link>
<description><![CDATA[
The ability to correctly predict the functional role of proteins from their amino acid sequences would significantly advance biological studies at the molecular level by improving our ability to understand the biochemical capability of biological organisms from their genomic sequence. Existing methods that are geared towards protein function prediction or annotation mostly use alignment-based approaches and probabilistic models such as Hidden-Markov Models. In this work we introduce a deep learning architecture (Function Identification with Neural Descriptions or FIND) which performs protein annotation from primary sequence. The accuracy of our methods matches state of the art techniques, such as protein classifiers based on Hidden Markov Models. Further, our approach allows for model introspection via a neural attention mechanism, which weights parts of the amino acid sequence proportionally to their relevance for functional assignment. In this way, the attention weights automatically uncover structurally and functionally relevant features of the classified protein and find novel functional motifs in previously uncharacterized proteins. While this model is applicable to any database of proteins, we chose to apply this model to superfamilies of homologous proteins, with the aim of extracting features inherent to divergent protein families within a larger superfamily. This provided insight into the functional diversification of an enzyme superfamily and its adaptation to different physiological contexts. We tested our approach on three families (nitrogenases, cytochrome bd-type oxygen reductases and heme-copper oxygen reductases) and present a detailed analysis of the sequence characteristics identified in previously characterized proteins in the heme-copper oxygen reductase (HCO) superfamily. These are correlated with their catalytic relevance and evolutionary history. FIND was then applied to discover features in previously uncharacterized members of the HCO superfamily, providing insight into their unique sequence features. This modeling approach demonstrates the power of neural networks to recognize patterns in large datasets and can be utilized to discover biochemically and structurally important features in proteins from their amino acid sequences.nnAuthor summary
]]></description>
<dc:creator>Murali, R.</dc:creator>
<dc:creator>Hemp, J.</dc:creator>
<dc:creator>Orphan, V.</dc:creator>
<dc:creator>Bisk, Y.</dc:creator>
<dc:date>2019-03-30</dc:date>
<dc:identifier>doi:10.1101/592808</dc:identifier>
<dc:title><![CDATA[FIND: Identifying Functionally and Structurally Important Features in Protein Sequences with Deep Neural Networks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/594325v1?rss=1">
<title>
<![CDATA[
First-principles prediction of the information processing capacity of a simple genetic circuit 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/594325v1?rss=1</link>
<description><![CDATA[
Given the stochastic nature of gene expression, genetically identical cells exposed to the same environmental inputs will produce different outputs. This heterogeneity has been hypothesized to have consequences for how cells are able to survive in changing environments. Recent work has explored the use of information theory as a framework to understand the accuracy with which cells can ascertain the state of their surroundings. Yet the predictive power of these approaches is limited and has not been rigorously tested using precision measurements. To that end, we generate a minimal model for a simple genetic circuit in which all parameter values for the model come from independently published data sets. We then predict the information processing capacity of the genetic circuit for a suite of biophysical parameters such as protein copy number and protein-DNA affinity. We compare these parameter-free predictions with an experimental determination of protein expression distributions and the resulting information processing capacity of E. coli cells. We find that our minimal model captures the scaling of the cell-to-cell variability in the data and the inferred information processing capacity of our simple genetic circuit up to a systematic deviation.
]]></description>
<dc:creator>Razo-Mejia, M.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2019-03-31</dc:date>
<dc:identifier>doi:10.1101/594325</dc:identifier>
<dc:title><![CDATA[First-principles prediction of the information processing capacity of a simple genetic circuit]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/594879v1?rss=1">
<title>
<![CDATA[
Quantitative characterization of random partitioning in the evolution of plasmid-encoded traits 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/594879v1?rss=1</link>
<description><![CDATA[
Plasmids are found across bacteria, archaea, and eukaryotes and play an important role in evolution. Plasmids exist at different copy numbers, the number of copies of the plasmid per cell, ranging from a single plasmid per cell to hundreds of plasmids per cell. This feature of a copy number greater than one can lead to a population of plasmids within a single cell that are not identical clones of one another, but rather have individual mutations that make a given plasmid unique. During cell division, this population of plasmids is partitioned into the two daughter cells, resulting in a random distribution of different plasmid variants in each daughter. In this study, we use stochastic simulations to investigate how random plasmid partitioning compares to a perfect partitioning model. Our simulation results demonstrate that random plasmid partitioning accelerates mutant allele fixation when the allele is beneficial and the selection is in an additive or recessive regime where increasing the copy number of the beneficial allele results in additional benefit for the host. This effect does not depend on the size of the benefit conferred or the mutation rate, but is magnified by increasing plasmid copy number.
]]></description>
<dc:creator>Halleran, A. D.</dc:creator>
<dc:creator>Flores-Bautista, E.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2019-03-31</dc:date>
<dc:identifier>doi:10.1101/594879</dc:identifier>
<dc:title><![CDATA[Quantitative characterization of random partitioning in the evolution of plasmid-encoded traits]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/595157v1?rss=1">
<title>
<![CDATA[
Biomolecular Contrast Agents for Optical Coherence Tomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/595157v1?rss=1</link>
<description><![CDATA[
Optical coherence tomography (OCT) has gained wide adoption in biological and medical imaging due to its exceptional tissue penetration, 3D imaging speed and rich contrast. However, OCT plays a relatively small role in molecular and cellular imaging due to the lack of suitable biomolecular contrast agents. In particular, while the green fluorescent protein has provided revolutionary capabilities to fluorescence microscopy by connecting it to cellular functions such as gene expression, no equivalent reporter gene is currently available for OCT. Here we introduce gas vesicles, a unique class of naturally evolved gas-filled protein nanostructures, as the first genetically encodable OCT contrast agents. The differential refractive index of their gas compartments relative to surrounding aqueous tissue and their nanoscale motion enables gas vesicles to be detected by static and dynamic OCT at picomolar concentrations. Furthermore, the OCT contrast of gas vesicles can be selectively erased in situ with ultrasound, allowing unambiguous assignment of their location. In addition, gas vesicle clustering modulates their temporal signal, enabling the design of dynamic biosensors. We demonstrate the use of gas vesicles as reporter genes in bacterial colonies and as purified contrast agents in vivo in the mouse retina. Our results expand the utility of OCT as a unique photonic modality to image a wider variety of cellular and molecular processes.
]]></description>
<dc:creator>Lu, G. J.</dc:creator>
<dc:creator>Chou, L.-d.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Patel, A. K.</dc:creator>
<dc:creator>Welsbie, D. S.</dc:creator>
<dc:creator>Chao, D. L.</dc:creator>
<dc:creator>Ramalingam, T.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2019-03-31</dc:date>
<dc:identifier>doi:10.1101/595157</dc:identifier>
<dc:title><![CDATA[Biomolecular Contrast Agents for Optical Coherence Tomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/614545v1?rss=1">
<title>
<![CDATA[
A Method for Cost-Effective and Rapid Characterization of Engineered T7-based Transcription Factors by Cell-Free Protein Synthesis Reveals Insights into the Regulation of T7 RNA Polymerase-Driven Expression 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/614545v1?rss=1</link>
<description><![CDATA[
The T7 bacteriophage RNA polymerase (T7 RNAP) serves as a model for understanding RNA synthesis, as a tool for protein expression, and as an actuator for synthetic gene circuit design in bacterial cells and cell-free extract. T7 RNAP is an attractive tool for orthogonal protein expression in bacteria owing to its compact single subunit structure and orthogonal promoter specificity. Understanding the mechanisms underlying T7 RNAP regulation is important to the design of engineered T7-based transcription factors, which can be used in gene circuit design. To explore regulatory mechanisms for T7 RNAP-driven expression, we developed a rapid and cost-effective method to characterize engineered T7-based transcription factors using cell-free protein synthesis and an acoustic liquid handler. Using this method, we investigated the effects of the tetracycline operators proximity to the T7 promoter on the regulation of T7 RNAP-driven expression. Our results reveal a mechanism for regulation that functions by interfering with the transition of T7 RNAP from initiation to elongation and validates the use of the method described here to engineer future T7-based transcription factors.nnHighlightsO_LIDevelopment of a rapid and cost-effective method for screening synthetic promoters.nC_LIO_LIInsights into the regulation of engineered T7-based transcription factors and T7 RNAP enzyme kinetics.nC_LIO_LIValidation of this method by comparison with the T7 RNAP kinetic model.nC_LI
]]></description>
<dc:creator>McManus, J.</dc:creator>
<dc:creator>Murray, R.</dc:creator>
<dc:creator>Emanuel, P.</dc:creator>
<dc:creator>Lux, M.</dc:creator>
<dc:date>2019-04-20</dc:date>
<dc:identifier>doi:10.1101/614545</dc:identifier>
<dc:title><![CDATA[A Method for Cost-Effective and Rapid Characterization of Engineered T7-based Transcription Factors by Cell-Free Protein Synthesis Reveals Insights into the Regulation of T7 RNA Polymerase-Driven Expression]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-04-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/619643v1?rss=1">
<title>
<![CDATA[
The Contribution of Parietal Cortex to Visual Salience 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/619643v1?rss=1</link>
<description><![CDATA[
Unique stimuli stand out. In spite of an abundance of competing sensory stimuli, the detection of the most salient ones occurs without effort, and that detection contributes to the guidance of adaptive behavior. Neurons sensitive to the salience of visual stimuli are widespread throughout the primate visual system and are thought to shape the selection of visual targets. However, mechanisms underlying the representation of salience remain elusive. Among the possible candidates are areas within posterior parietal cortex, which appear to be crucial in the control of visual attention and are thought to play a unique role in representing stimulus salience. Here we show that reversible inactivation of parietal cortex not only selectively reduces the representation of visual salience within the brain, but it also diminishes the influence of salience on visually guided behavior. These results demonstrate a distinct contribution of parietal areas to vision and visual attention.
]]></description>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>Zirnsak, M.</dc:creator>
<dc:creator>Vega, G. M.</dc:creator>
<dc:creator>Govil, E.</dc:creator>
<dc:creator>Lomber, S.</dc:creator>
<dc:creator>Moore, T.</dc:creator>
<dc:date>2019-04-28</dc:date>
<dc:identifier>doi:10.1101/619643</dc:identifier>
<dc:title><![CDATA[The Contribution of Parietal Cortex to Visual Salience]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-04-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/620567v1?rss=1">
<title>
<![CDATA[
Acoustically Detonated Biomolecules for Genetically Encodable Inertial Cavitation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/620567v1?rss=1</link>
<description><![CDATA[
Recent advances in molecular engineering and synthetic biology have made it possible for biomolecular and cell-based therapies to provide highly specific disease treatment. However, both the ability to spatially target the action of such therapies, and their range of effects on the target tissue remain limited. Here we show that biomolecules and cells can be engineered to deliver potent mechanical effects at specific locations inside the body under the direction of focused ultrasound. This capability is based on gas vesicles, a unique class of air-filled protein nanostructures derived from buoyant photosynthetic microbes. We show that low-frequency ultrasound can convert these nanoscale biomolecules into micron-scale cavitating bubbles, as demonstrated with acoustic measurements and ultrafast optical microscopy. This allows gas vesicles targeted to cell-surface receptors to serve as remotely detonated cell-killing agents. In addition, it allows cells genetically engineered to express gas vesicles to be triggered with ultrasound to lyse and release therapeutic payloads. We demonstrate these capabilities in vitro, in cellulo, and in vivo. This technology equips biomolecular and cellular therapeutics with unique capabilities for spatiotemporal control and mechanical action.
]]></description>
<dc:creator>Bar-Zion, A.</dc:creator>
<dc:creator>Nourmahnad, A.</dc:creator>
<dc:creator>Mittelstein, D.</dc:creator>
<dc:creator>Yoo, S.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Abedi, M.</dc:creator>
<dc:creator>Lee-Gosselin, A.</dc:creator>
<dc:creator>Maresca, D.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2019-04-29</dc:date>
<dc:identifier>doi:10.1101/620567</dc:identifier>
<dc:title><![CDATA[Acoustically Detonated Biomolecules for Genetically Encodable Inertial Cavitation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-04-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/631283v1?rss=1">
<title>
<![CDATA[
Aggregation of nontuberculous mycobacteria is regulated by carbon:nitrogen balance 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/631283v1?rss=1</link>
<description><![CDATA[
Nontuberculous mycobacteria (NTM) are emerging opportunistic pathogens that form biofilms in environmental reservoirs such as household water systems and aggregate into phagocytosis-resistant clusters during infection. NTM constitutively aggregate in vitro, a phenotype typically considered to be a by-product of the mycolic-acid-rich cell wall. While culturing a model NTM, Mycobacterium smegmatis, in rich medium, we fortuitously discovered that planktonic cells accumulated in the culture after [~]3 days. By providing selective pressure for bacteria that disperse earlier, we isolated a strain with two mutations in the oligopeptide permease operon (opp). A mutant lacking the opp operon ({Delta}opp) dispersed earlier and more completely than wildtype (WT). We show that {Delta}opps aggregation defect was nutrient related; aggregation was restored by non-peptide carbon sources. Experiments with WT M. smegmatis revealed that growth as aggregates is favored when carbon is replete, while dispersal can be induced by carbon starvation. In addition, under conditions of low available carbon relative to available nitrogen, M. smegmatis grows as planktonic cells. By adjusting carbon and nitrogen sources in defined medium, we tuned the cellular C:N ratio such that M. smegmatis grows either as aggregates or planktonic cells. Lastly, we tested the effect of C:N balance on aggregation in clinically relevant NTM. Altogether, we show that NTM aggregation is a controlled process that is regulated by the relative availability of carbon and nitrogen for metabolism. Because NTM aggregation is correlated with increased virulence, these results may contribute to targeted anti-biofilm therapeutics.nnImportanceFree-living bacteria can assemble into multicellular aggregates called biofilms. Biofilms help bacteria tolerate multiple stresses, including antibiotics and the host immune system. Differing environmental pressures have resulted in biofilm architecture and regulation varying among bacterial species and strains. Nontuberculous mycobacteria are a group of emerging opportunistic pathogens that utilize biofilms to adhere to household plumbing and showerheads and to avoid phagocytosis by host immune cells. Mycobacteria harbor a unique cell wall built chiefly of long chain mycolic acids that confers hydrophobicity and has been thought to cause constitutive aggregation in liquid media. Here we show that aggregation is instead a regulated process dictated by the balance of available carbon and nitrogen. Understanding that mycobacteria utilize metabolic cues to regulate the transition between planktonic and aggregated cells reveals an inroad to controlling aggregation through targeted therapeutics.
]]></description>
<dc:creator>DePas, W. H.</dc:creator>
<dc:creator>Bergkessel, M.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2019-05-08</dc:date>
<dc:identifier>doi:10.1101/631283</dc:identifier>
<dc:title><![CDATA[Aggregation of nontuberculous mycobacteria is regulated by carbon:nitrogen balance]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-05-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/632893v1?rss=1">
<title>
<![CDATA[
Quantitative visualization of gene expression in Pseudomonas aeruginosa aggregates reveals peak expression of alginate in the hypoxic zone 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/632893v1?rss=1</link>
<description><![CDATA[
It is well appreciated that oxygen- and nutrient-limiting gradients characterize microenvironments within chronic infections that foster bacterial tolerance to treatment and the immune response. However, determining how bacteria respond to these microenvironments has been limited by a lack of tools to study bacterial functions at the relevant spatial scales in situ. Here we report the application of the hybridization chain reaction (HCR) v3.0 to Pseudomonas aeruginosa aggregates as a step towards this end. As proof-of-principle, we visualize the expression of genes needed for the production of alginate (algD) and the dissimilatory nitrate reductase (narG). Using an inducible bacterial gene expression construct to calibrate the HCR signal, we were able to quantify algD and narG gene expression across microenvironmental gradients both within single aggregates and within aggregate populations using the Agar Block Biofilm Assay (ABBA). For the ABBA population, alginate gene expression was restricted to hypoxic regions within the environment (~40-200 M O2), as measured by an oxygen microelectrode. Within individual biofilm aggregates, cells proximal to the surface expressed alginate genes to a greater extent than interior cells. Lastly, mucoid biofilms consumed more oxygen than nonmucoid biofilms. These results establish that HCR has a sensitive dynamic range and can be used to resolve subtle differences in gene expression at spatial scales relevant to microbial assemblages. Because HCR v3.0 can be performed on diverse cell types, this methodological advance has the potential to enable quantitative studies of microbial gene expression in diverse contexts, including pathogen behavior in human chronic infections.nnImportanceThe visualization of microbial activities in natural environments is an important goal for numerous studies in microbial ecology, be the environment a sediment, soil, or infected human tissue. Here we report the application of the hybridization chain reaction (HCR) v3.0 to measure microbial gene expression in situ at single-cell resolution in aggregate biofilms. Using Pseudomonas aeruginosa with a tunable gene expression system, we show that this methodology is quantitative. Leveraging HCR v3.0 to measure gene expression within a P. aeruginosa aggregate, we find that bacteria just below the aggregate surface are the primary cells expressing genes that protect the population against antibiotics and the immune system. This observation suggests that therapies targeting bacteria growing with small amounts of oxygen may be most effective against these hard-to-treat infections. More generally, HCR v3.0 has potential for broad application into microbial activities in situ at small spatial scales.
]]></description>
<dc:creator>Jorth, P.</dc:creator>
<dc:creator>Spero, M.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2019-05-09</dc:date>
<dc:identifier>doi:10.1101/632893</dc:identifier>
<dc:title><![CDATA[Quantitative visualization of gene expression in Pseudomonas aeruginosa aggregates reveals peak expression of alginate in the hypoxic zone]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-05-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/638270v1?rss=1">
<title>
<![CDATA[
The Energetics of Molecular Adaptation in Transcriptional Regulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/638270v1?rss=1</link>
<description><![CDATA[
Mutation is a critical mechanism by which evolution explores the functional landscape of proteins. Despite our ability to experimentally inflict mutations at will, it remains difficult to link sequence-level perturbations to systems-level responses. Here, we present a framework centered on measuring changes in the free energy of the system to link individual mutations in an allosteric transcriptional repressor to the parameters which govern its response. We find the energetic effects of the mutations can be categorized into several classes which have characteristic curves as a function of the inducer concentration. We experimentally test these diagnostic predictions using the well-characterized LacI repressor of Escherichia coli, probing several mutations in the DNA binding and inducer binding domains. We find that the change in gene expression due to a point mutation can be captured by modifying only a subset of the model parameters that describe the respective domain of the wild-type protein. These parameters appear to be insulated, with mutations in the DNA binding domain altering only the DNA affinity and those in the inducer binding domain altering only the allosteric parameters. Changing these subsets of parameters tunes the free energy of the system in a way that is concordant with theoretical expectations. Finally, we show that the induction profiles and resulting free energies associated with pairwise double mutants can be predicted with quantitative accuracy given knowledge of the single mutants, providing an avenue for identifying and quantifying epistatic interactions.nnSummaryWe present a biophysical model of allosteric transcriptional regulation that directly links the location of a mutation within a repressor to the biophysical parameters that describe its behavior. We explore the phenotypic space of a repressor with mutations in either the inducer binding or DNA binding domains. Using the LacI repressor in E. coli, we make sharp, falsifiable predictions and use this framework to generate a null hypothesis for how double mutants behave given knowledge of the single mutants. Linking mutations to the parameters which govern the system allows for quantitative predictions of how the free energy of the system changes as a result, permitting coarse graining of high-dimensional data into a single-parameter description of the mutational consequences.
]]></description>
<dc:creator>Chure, G.</dc:creator>
<dc:creator>Razo-Mejia, M.</dc:creator>
<dc:creator>Belliveau, N. M.</dc:creator>
<dc:creator>Einav, T.</dc:creator>
<dc:creator>Kaczmarek, Z. A.</dc:creator>
<dc:creator>Barnes, S. L.</dc:creator>
<dc:creator>Lewis, M.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2019-05-15</dc:date>
<dc:identifier>doi:10.1101/638270</dc:identifier>
<dc:title><![CDATA[The Energetics of Molecular Adaptation in Transcriptional Regulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-05-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/640276v1?rss=1">
<title>
<![CDATA[
An automated model reduction tool to guide the design and analysis of synthetic biological circuits 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/640276v1?rss=1</link>
<description><![CDATA[
We present an automated model reduction algorithm that uses quasi-steady state approximation to minimize the error between the desired outputs. Additionally, the algorithm minimizes the sensitivity of the error with respect to parameters to ensure robust performance of the reduced model in the presence of parametric uncertainties. We develop the theory for this model reduction algorithm and present the implementation of the algorithm that can be used to perform model reduction of given SBML models. To demonstrate the utility of this algorithm, we consider the design of a synthetic biological circuit to control the population density and composition of a consortium consisting of two different cell strains. We show how the model reduction algorithm can be used to guide the design and analysis of this circuit.
]]></description>
<dc:creator>Pandey, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2019-05-17</dc:date>
<dc:identifier>doi:10.1101/640276</dc:identifier>
<dc:title><![CDATA[An automated model reduction tool to guide the design and analysis of synthetic biological circuits]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-05-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/653444v1?rss=1">
<title>
<![CDATA[
MCH4 is a multicopy suppressor of glycine toxicity in Saccharomyces cerevisiae 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/653444v1?rss=1</link>
<description><![CDATA[
Saccharomyces cerevisiae can either import amino acids from the surrounding or synthesize inside the cell, and both processes are tightly regulated. Disruption of such regulation can result in amino acid toxicity to the cell through mechanisms that are poorly understood. In this study we make use of a mutant strain with deregulated general amino acid permease gene whose growth is inhibited by low concentrations of several amino acids. We carry out multicopy suppression screen with several toxic amino acids and identify MCH4 as a gene that suppresses inhibitory effects of glycine. We find that expression of MCH4 is regulated by osmotic shock but not other kinds of stress. These findings are discussed in the context of possible mechanisms of amino acid toxicity.
]]></description>
<dc:creator>Melnykov, A. V.</dc:creator>
<dc:creator>Elson, E. L.</dc:creator>
<dc:date>2019-05-29</dc:date>
<dc:identifier>doi:10.1101/653444</dc:identifier>
<dc:title><![CDATA[MCH4 is a multicopy suppressor of glycine toxicity in Saccharomyces cerevisiae]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-05-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/653600v1?rss=1">
<title>
<![CDATA[
Repurposing a macromolecular machine: Architecture and evolution of the F7 chemosensory system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/653600v1?rss=1</link>
<description><![CDATA[
How complex, multi-component macromolecular machines evolved remains poorly understood. Here we reveal the evolutionary origins of the chemosensory machinery that controls flagellar motility in Escherichia coli. We first identified ancestral forms still present in Vibrio cholerae, Pseudomonas aeruginosa, Shewanella oneidensis and Methylomicrobium alcaliphilum, characterizing their structures by electron cryotomography and finding evidence that they function in a stress response pathway. Using bioinformatics, we then traced the evolution of the system through {gamma}-Proteobacteria, pinpointing key evolutionary events that led to the machine now seen in E. coli. Our results suggest that two ancient chemosensory systems with different inputs and outputs (F6 and F7) existed contemporaneously, with one (F7) ultimately taking over the inputs and outputs of the other (F6), which was subsequently lost.
]]></description>
<dc:creator>Ortega, D. R.</dc:creator>
<dc:creator>Subramanian, P.</dc:creator>
<dc:creator>Mann, P.</dc:creator>
<dc:creator>Kjaer, A.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Watts, K. J.</dc:creator>
<dc:creator>Pirbadian, S.</dc:creator>
<dc:creator>Collins, D. A.</dc:creator>
<dc:creator>Kooger, R.</dc:creator>
<dc:creator>Kalyuzhnaya, M. G.</dc:creator>
<dc:creator>Ringgaard, S.</dc:creator>
<dc:creator>Briegel, A.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2019-05-30</dc:date>
<dc:identifier>doi:10.1101/653600</dc:identifier>
<dc:title><![CDATA[Repurposing a macromolecular machine: Architecture and evolution of the F7 chemosensory system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-05-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/654756v1?rss=1">
<title>
<![CDATA[
Chemical Impacts of the Microbiome Across Scales Reveal Novel Conjugated Bile Acids 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/654756v1?rss=1</link>
<description><![CDATA[
A mosaic of cross-phyla chemical interactions occurs between all metazoans and their microbiomes. In humans, the gut harbors the heaviest microbial load, but many organs, particularly those with a mucosal surface, associate with highly adapted and evolved microbial consortia1. The microbial residents within these organ systems are increasingly well characterized, yielding a good understanding of human microbiome composition, but we have yet to elucidate the full chemical impact the microbiome exerts on an animal and the breadth of the chemical diversity it contributes2. A number of molecular families are known to be shaped by the microbiome including short-chain fatty acids, indoles, aromatic amino acid metabolites, complex polysaccharides, and host lipids; such as sphingolipids and bile acids3-11. These metabolites profoundly affect host physiology and are being explored for their roles in both health and disease. Considering the diversity of the human microbiome, numbering over 40,000 operational taxonomic units12, a plethora of molecular diversity remains to be discovered. Here, we use unique mass spectrometry informatics approaches and data mapping onto a murine 3D-model13-15 to provide an untargeted assessment of the chemical diversity between germ-free (GF) and colonized mice (specific-pathogen free, SPF), and report the finding of novel bile acids produced by the microbiome in both mice and humans that have evaded characterization despite 170 years of research on bile acid chemistry16.
]]></description>
<dc:creator>Quinn, R. A.</dc:creator>
<dc:creator>Vrbanac, A.</dc:creator>
<dc:creator>Melnik, A. V.</dc:creator>
<dc:creator>Patras, K. A.</dc:creator>
<dc:creator>Christy, M.</dc:creator>
<dc:creator>Nelson, A. T.</dc:creator>
<dc:creator>Aksenov, A. A.</dc:creator>
<dc:creator>Tripathi, A.</dc:creator>
<dc:creator>Humphrey, G.</dc:creator>
<dc:creator>da Silva, R.</dc:creator>
<dc:creator>Bussell, R.</dc:creator>
<dc:creator>Thron, T.</dc:creator>
<dc:creator>Wang, M.</dc:creator>
<dc:creator>Vargas, F.</dc:creator>
<dc:creator>Gauglitz, J.</dc:creator>
<dc:creator>Meehan, M. J.</dc:creator>
<dc:creator>Poulsen, O.</dc:creator>
<dc:creator>Boland, B. S.</dc:creator>
<dc:creator>Chang, J. T.</dc:creator>
<dc:creator>Sandborn, W. J.</dc:creator>
<dc:creator>Lim, M.</dc:creator>
<dc:creator>Garg, N.</dc:creator>
<dc:creator>Lumeng, J.</dc:creator>
<dc:creator>Kazmierczak, B. I.</dc:creator>
<dc:creator>Jain, R.</dc:creator>
<dc:creator>Egan, M.</dc:creator>
<dc:creator>Rhee, K. E.</dc:creator>
<dc:creator>Haddad, G. G.</dc:creator>
<dc:creator>Siegel, D.</dc:creator>
<dc:creator>Mazmanian, S.</dc:creator>
<dc:creator>Nizet, V.</dc:creator>
<dc:creator>Knight, R.</dc:creator>
<dc:creator>Dorrestein, P. C.</dc:creator>
<dc:date>2019-06-03</dc:date>
<dc:identifier>doi:10.1101/654756</dc:identifier>
<dc:title><![CDATA[Chemical Impacts of the Microbiome Across Scales Reveal Novel Conjugated Bile Acids]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-06-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/658401v1?rss=1">
<title>
<![CDATA[
RNA velocity and protein acceleration from single-cell multiomics experiments 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/658401v1?rss=1</link>
<description><![CDATA[
The simultaneous quantification of protein and RNA makes possible the inference of past, present and future cell states from single experimental snapshots. To enable such temporal analysis from multimodal single-cell experiments, we introduce an extension of the RNA velocity method that leverages estimates of unprocessed transcript and protein abundances to extrapolate cell states. We apply the model to four datasets and demonstrate consistency among landscapes and phase portraits.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Svensson, V.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2019-06-06</dc:date>
<dc:identifier>doi:10.1101/658401</dc:identifier>
<dc:title><![CDATA[RNA velocity and protein acceleration from single-cell multiomics experiments]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-06-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/659714v1?rss=1">
<title>
<![CDATA[
Bacterial Controller Aided Wound Healing: A Case Study in Dynamical Population Controller Design 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/659714v1?rss=1</link>
<description><![CDATA[
Wound healing is a complicated biological process consisting of many types of cellular dynamics and functions regulated by chemical and molecular signals. Recent advances in synthetic biology have made it possible to predictably design and build closed-loop controllers that can function appropriately alongside biological species. In this paper we develop a simple dynamical population model mimicking the sequential relay-like dynamics of cellular populations involved in the wound healing process. Our model consists of four nodes and five signals whose parameters we can tune to simulate various chronic healing conditions. We also develop a set of regulator functions based on type-1 incoherent feed forward loops (IFFL) that can sense the change from acute healing to incomplete chronic wounds, improving the system in a timely manner. Both the wound healing and type-1 IFFL controller architectures are compatible with available synthetic biology experimental tools for potential applications.Competing Interest StatementThe authors have declared no competing interest.View Full Text
]]></description>
<dc:creator>Green, L. N.</dc:creator>
<dc:creator>Hu, C. Y.</dc:creator>
<dc:creator>Ren, X. Y.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2019-06-04</dc:date>
<dc:identifier>doi:10.1101/659714</dc:identifier>
<dc:title><![CDATA[Bacterial Controller Aided Wound Healing: A Case Study in Dynamical Population Controller Design]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-06-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/666040v1?rss=1">
<title>
<![CDATA[
Defining the Energetic Costs of Cellular Structures 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/666040v1?rss=1</link>
<description><![CDATA[
All cellular structures are assembled from molecular building blocks, and molecular building blocks incur energetic costs to the cell. In an energy-limited environment, the energetic cost of a cellular structure imposes a fitness cost and impacts a cells evolutionary trajectory. While the importance of energetic considerations was realized for decades, the distinction between direct energetic costs expended by the cell and potential energy that the cell diverts into cellular biomass components, which we define as the opportunity cost, was not explicitly made, leading to large differences in values for energetic costs of molecular building blocks used in the literature. We describe a framework that defines and separates various components relevant for estimating the energetic costs of molecular building blocks and the resulting cellular structures. This distinction among energetic costs is an essential step towards discussing the conversion of an energetic cost to a corresponding fitness cost.
]]></description>
<dc:creator>Mahmoudabadi, G.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:creator>Lynch, M.</dc:creator>
<dc:creator>Milo, R.</dc:creator>
<dc:date>2019-06-10</dc:date>
<dc:identifier>doi:10.1101/666040</dc:identifier>
<dc:title><![CDATA[Defining the Energetic Costs of Cellular Structures]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-06-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/667709v1?rss=1">
<title>
<![CDATA[
Multi-scale dynamical modelling of T-cell development from an early thymic progenitor state to lineage commitment 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/667709v1?rss=1</link>
<description><![CDATA[
Thymic development of committed pro-T-cells from multipotent hematopoietic precursors offers a unique opportunity to dissect the molecular circuitry establishing cell identity in response to environmental signals. This transition encompasses programmed shutoff of stem/progenitor genes, upregulation of T-cell specification genes, extensive proliferation, and commitment after a delay. We have incorporated these factors, as well as new single cell gene expression and developmental kinetics data, into a three-level dynamic model of commitment based upon regulation of the commitment gene Bcl11b. The first level is a core gene regulatory network architecture determined by transcription factor perturbation data, the second a stochastically controlled epigenetic gate, and the third a proliferation model validated by growth and commitment kinetics measured at single-cell levels. Using expression values consistent with single molecule RNA-FISH measurements of key transcription factors, this single-cell model exhibits state switching consistent with measured population and clonal proliferation and commitment times. The resulting multi-scale model provides a powerful mechanistic framework for dissecting commitment dynamics.
]]></description>
<dc:creator>Olariu, V.</dc:creator>
<dc:creator>Yui, M.</dc:creator>
<dc:creator>Krupinski, P.</dc:creator>
<dc:creator>Zhou, W.</dc:creator>
<dc:creator>Deichmann, J.</dc:creator>
<dc:creator>Rothenberg, E. V.</dc:creator>
<dc:creator>Peterson, C.</dc:creator>
<dc:date>2019-06-11</dc:date>
<dc:identifier>doi:10.1101/667709</dc:identifier>
<dc:title><![CDATA[Multi-scale dynamical modelling of T-cell development from an early thymic progenitor state to lineage commitment]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-06-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/672931v1?rss=1">
<title>
<![CDATA[
A technology-agnostic long-read analysis pipeline for transcriptome discovery and quantification 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/672931v1?rss=1</link>
<description><![CDATA[
Alternative splicing is widely acknowledged to be a crucial regulator of gene expression and is a key contributor to both normal developmental processes and disease states. While cost-effective and accurate for quantification, short-read RNA-seq lacks the ability to resolve full-length transcript isoforms despite increasingly sophisticated computational methods. Long-read sequencing platforms such as Pacific Biosciences (PacBio) and Oxford Nanopore (ONT) bypass the transcript reconstruction challenges of short reads. Here we introduce TALON, the ENCODE4 pipeline for platform-independent analysis of long-read transcriptomes. We apply TALON to the GM12878 cell line and show that while both PacBio and ONT technologies perform well at full-transcript discovery and quantification, each displayed distinct technical artifacts. We further apply TALON to mouse hippocampus and cortex transcriptomes and find that 422 genes found in these regions have more reads associated with novel isoforms than with annotated ones. We demonstrate that TALON is a capable of tracking both known and novel transcript models as well as their expression levels across datasets for both simple studies and in larger projects. These properties will enable TALON users to move beyond the limitations of short-read data to perform isoform discovery and quantification in a uniform manner on existing and future long-read platforms.
]]></description>
<dc:creator>Wyman, D.</dc:creator>
<dc:creator>Balderrama-Gutierrez, G.</dc:creator>
<dc:creator>Reese, F.</dc:creator>
<dc:creator>Jiang, S.</dc:creator>
<dc:creator>Rahmanian, S.</dc:creator>
<dc:creator>Zeng, W.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>Trout, D.</dc:creator>
<dc:creator>England, W.</dc:creator>
<dc:creator>Chu, S.</dc:creator>
<dc:creator>Spitale, R. C.</dc:creator>
<dc:creator>Tenner, A. J.</dc:creator>
<dc:creator>Wold, B.</dc:creator>
<dc:creator>Mortazavi, A.</dc:creator>
<dc:date>2019-06-18</dc:date>
<dc:identifier>doi:10.1101/672931</dc:identifier>
<dc:title><![CDATA[A technology-agnostic long-read analysis pipeline for transcriptome discovery and quantification]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-06-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/673285v1?rss=1">
<title>
<![CDATA[
Modular and efficient pre-processing of single-cell RNA-seq 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/673285v1?rss=1</link>
<description><![CDATA[
Analysis of single-cell RNA-seq data begins with pre-processing of sequencing reads to generate count matrices. We investigate algorithm choices for the challenges of pre-processing, and describe a workflow that balances efficiency and accuracy. Our workflow is based on the kallisto (https://pachterlab.github.io/kallisto/) and bustools (https://bustools.github.io/) programs, and is near-optimal in speed and memory. The workflow is modular, and we demonstrate its flexibility by showing how it can be used for RNA velocity analyses. Documentation and tutorials for using the kallisto | bus workflow are available at https://www.kallistobus.tools/.
]]></description>
<dc:creator>Melsted, P.</dc:creator>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>da Veiga Beltrame, E.</dc:creator>
<dc:creator>Lu, L.</dc:creator>
<dc:creator>Hjorleifsson, K. E.</dc:creator>
<dc:creator>Gehring, J.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2019-06-17</dc:date>
<dc:identifier>doi:10.1101/673285</dc:identifier>
<dc:title><![CDATA[Modular and efficient pre-processing of single-cell RNA-seq]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-06-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/675967v1?rss=1">
<title>
<![CDATA[
Transcriptome Dynamics Reveals Progressive Transition from Effector to Memory in CD4+ T cells. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/675967v1?rss=1</link>
<description><![CDATA[
CD4+ T cells are repositories of immune memory, conferring enhanced immunity to many infectious agents. Studies of acute viral and bacterial infection suggest that memory CD4+ T cells develop directly from effectors. However, delineating these dynamic developmental pathways has been challenging. Here, we used high-resolution single-cell RNA-seq and temporal mixture modelling to examine the fate of Th1 and Tfh effector cells during non-lethal Plasmodium infection in mice. We observed linear Th1 and Tfh pathways towards memory, characterized by progressive halving in the numbers of genes expressed, and partial transcriptomic coalescence. Low-level persisting infection diverted but did not block these pathways. We observed in the Th1-pathway a linear transition from Th1 through a Tr1 state to TEM cells, which were then poised for Th1 re-call. The Tfh-pathway exhibited a modest Th1-signature throughout, with little evidence of Tr1 development, and co-expression of TCM and memory Tfh markers. Thus, we present a high-resolution atlas of transcriptome dynamics for naive to memory transitions in CD4+ T cells. We also defined a subset of memory-associated genes, including transcription factors Id2 and Maf, whose expression increased progressively against the background of transcriptomic quiescence. Single-cell ATAC-seq revealed substantial heterogeneity in chromatin accessibility in single effectors, which was extensively, though incompletely reset and homogenized in memory. Our data reveal that linear transitions from effector to memory occur in a progressive manner over several weeks, suggesting opportunities for manipulating CD4+ T cell memory after primary infection.nnHighlightsO_LIscRNA-seq reveals progressive transition from effector to memory in CD4+ T cells.nC_LIO_LITranscriptome dynamics suggest linear not branching models for memory development.nC_LIO_LIA subset of genes associates with gradual onset of CD4+ T cell memory.nC_LIO_LITh1/Tfh predisposition varies among clonotypes with identical antigen-specificity.nC_LIO_LIscATAC-seq uncovers non-coding "memory" elements in the genome.nC_LI
]]></description>
<dc:creator>Soon, M. S. F.</dc:creator>
<dc:creator>Lee, H. J.</dc:creator>
<dc:creator>Engel, J. A.</dc:creator>
<dc:creator>Straube, J.</dc:creator>
<dc:creator>Thomas, B. S.</dc:creator>
<dc:creator>Clarke, L. S.</dc:creator>
<dc:creator>Laohamonthonkul, P.</dc:creator>
<dc:creator>Pernold, C. P. S.</dc:creator>
<dc:creator>Haldar, R. N.</dc:creator>
<dc:creator>Williams, C. G.</dc:creator>
<dc:creator>Lansink, L. I. M.</dc:creator>
<dc:creator>Koufariotis, R.</dc:creator>
<dc:creator>Lakis, V.</dc:creator>
<dc:creator>Wood, S.</dc:creator>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>James, K. R.</dc:creator>
<dc:creator>Lönnberg, T.</dc:creator>
<dc:creator>Lane, S. W.</dc:creator>
<dc:creator>Davenport, M. P.</dc:creator>
<dc:creator>Khoury, D. S.</dc:creator>
<dc:creator>Svensson, V.</dc:creator>
<dc:creator>Teichmann, S. A.</dc:creator>
<dc:creator>Haque, A.</dc:creator>
<dc:date>2019-06-19</dc:date>
<dc:identifier>doi:10.1101/675967</dc:identifier>
<dc:title><![CDATA[Transcriptome Dynamics Reveals Progressive Transition from Effector to Memory in CD4+ T cells.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-06-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/679704v1?rss=1">
<title>
<![CDATA[
Interactions with presynaptic photoreceptors mediated by the Dpr11 and DIP-γ cell surface proteins control selection and survival of Drosophila amacrine neurons 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/679704v1?rss=1</link>
<description><![CDATA[
Drosophila R7 UV photoreceptors (PRs) are divided into yellow (y) and pale (p) subtypes with different wavelength sensitivities. yR7 PRs express the Dpr11 cell surface protein and are presynaptic to Dm8 amacrine neurons (yDm8) that express Dpr11s binding partner DIP-{gamma}, while pR7 PRs synapse onto DIP-{gamma}-negative pDm8 neurons. Dpr11 and DIP-{gamma} expression patterns define yellow and pale medulla color vision circuits that project to higher-order areas. DIP- {gamma} and dpr11 mutations affect the morphology of yDm8 arbors in the yellow circuit. yDm8 neurons are generated in excess during development and compete for presynaptic yR7 partners. Transsynaptic interactions between Dpr11 and DIP-{gamma} are required for generation of neurotrophic signals that allow yDm8 neurons to survive. yDm8 and pDm8 neurons do not normally compete for neurotrophic support, but can be forced to do so by manipulating R7 subtype fates. DIP-{gamma}-Dpr11 interactions allow yDm8 neurons to select yR7 PRs as their home column partners.
]]></description>
<dc:creator>Menon, K.</dc:creator>
<dc:creator>Kulkarni, V.</dc:creator>
<dc:creator>Takemura, S.-y.</dc:creator>
<dc:creator>Anaya, M.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:date>2019-06-22</dc:date>
<dc:identifier>doi:10.1101/679704</dc:identifier>
<dc:title><![CDATA[Interactions with presynaptic photoreceptors mediated by the Dpr11 and DIP-γ cell surface proteins control selection and survival of Drosophila amacrine neurons]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-06-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/683318v1?rss=1">
<title>
<![CDATA[
Ciliary photoreceptors in sea urchin larvae indicate pan-deuterostome cell type conservation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/683318v1?rss=1</link>
<description><![CDATA[
One of the signatures of evolutionarily related cell types is the expression of similar combinations of transcription factors in distantly related animals. Here we present evidence that sea urchin larvae possess bilateral clusters of ciliary photoreceptors that are positioned in the oral/anterior apical neurogenic domain and associated with pigment cells. The expression of synaptotagmin indicates that the photoreceptors are neurons. Immunostaining shows that the sea urchin photoreceptors express an RGR/GO-opsin, opsin3.2, which co-localizes with tubulin on immotile cilia on the cell surface. Furthermore, orthologs of several transcription factors expressed in vertebrate photoreceptors are expressed in sea urchin ciliary photoreceptors, including Otx, Six3, Tbx2/3, and Rx, a transcription factor typically associated with ciliary photoreceptors. Analysis of gene expression during sea urchin development indicates that the photoreceptors derive from the anterior apical neurogenic domain. Thus, based on location, developmental origin, and transcription factor expression, sea urchin ciliary photoreceptors are likely homologous to vertebrate rods and cones. However, we found that genes typically involved in eye development in many animals, including pax6, six1/2, eya, and dac, are not expressed in sea urchin ciliary photoreceptors. Instead, all four genes are co-expressed in the hydropore canal, indicating that these genes operate as a module in an unrelated developmental context. Thus, based on current evidence, we conclude that at least within deuterostomes, ciliary photoreceptors share a common evolutionary origin and express a shared regulatory state that includes Rx, Otx, and Six3, but not transcription factors that are commonly associated with the retinal determination circuit.
]]></description>
<dc:creator>Valencia, J. E.</dc:creator>
<dc:creator>Feuda, R.</dc:creator>
<dc:creator>Mellott, D. O.</dc:creator>
<dc:creator>Burke, R.</dc:creator>
<dc:creator>Peter, I. S.</dc:creator>
<dc:date>2019-06-27</dc:date>
<dc:identifier>doi:10.1101/683318</dc:identifier>
<dc:title><![CDATA[Ciliary photoreceptors in sea urchin larvae indicate pan-deuterostome cell type conservation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-06-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/690875v1?rss=1">
<title>
<![CDATA[
Restructuring of amygdala subregion apportion across adolescence 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/690875v1?rss=1</link>
<description><![CDATA[
Total amygdala volumes develop in association with sex and puberty, and postmortem studies find neuronal numbers increase in a nuclei specific fashion across development. Thus, amygdala subregions and composition may evolve with age. Our goal was to examine if amygdala subregion absolute volumes and/or relative proportion varies as a function of age, sex, or puberty in a large sample of typically developing adolescents (N=408, 43% female, 10-17 years). Utilizing the in vivo CIT168 atlas, we quantified 9 subregions and implemented Generalized Additive Mixed Models to capture potential non-linear associations with age and pubertal status between sexes. Only males showed significant age associations with the basolateral ventral and paralaminar subdivision (BLVPL), central nucleus (CEN), and amygdala transition area (ATA). Again, only males showed relative differences in the proportion of the BLVPL, CEN, ATA, along with lateral (LA) and amygdalostriatal transition area (ASTA), with age. Using a best-fit modeling approach, age, and not puberty, was found to drive these associations. The results suggest that amygdala subregions show unique developmental patterns with age in males across adolescence. Future research is warranted to determine if our findings may contribute to sex differences in mental health that emerge across adolescence.
]]></description>
<dc:creator>Campbell, C. E.</dc:creator>
<dc:creator>Mezher, A. F.</dc:creator>
<dc:creator>Eckel, S. P.</dc:creator>
<dc:creator>Tyszka, J. M.</dc:creator>
<dc:creator>Pauli, W. M.</dc:creator>
<dc:creator>Nagel, B. J.</dc:creator>
<dc:creator>Herting, M. M.</dc:creator>
<dc:date>2019-07-09</dc:date>
<dc:identifier>doi:10.1101/690875</dc:identifier>
<dc:title><![CDATA[Restructuring of amygdala subregion apportion across adolescence]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-07-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/691105v1?rss=1">
<title>
<![CDATA[
Genetically encoded nanostructures enable acoustic manipulation of engineered cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/691105v1?rss=1</link>
<description><![CDATA[
The ability to mechanically manipulate and control the spatial arrangement of biological materials is a critical capability in biomedicine and synthetic biology. Ultrasound has the ability to manipulate objects with high spatial and temporal precision via acoustic radiation force, but has not been used to directly control biomolecules or genetically defined cells. Here, we show that gas vesicles (GVs), a unique class of genetically encoded gas-filled protein nanostructures, can be directly manipulated and patterned by ultrasound and enable acoustic control of genetically engineered GV-expressing cells. Due to their differential density and compressibility relative to water, GVs experience sufficient acoustic radiation force to allow these biomolecules to be moved with acoustic standing waves, as demonstrated within microfluidic devices. Engineered variants of GVs differing in their mechanical properties enable multiplexed actuation and act as sensors of acoustic pressure. Furthermore, when expressed inside genetically engineered bacterial cells, GVs enable these cells to be selectively manipulated with sound waves, allowing patterning, focal trapping and translation with acoustic fields. This work establishes the first genetically encoded nanomaterial compatible with acoustic manipulation, enabling molecular and cellular control in a broad range of contexts.
]]></description>
<dc:creator>Wu, D.</dc:creator>
<dc:creator>Baresch, D.</dc:creator>
<dc:creator>Cook, C.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Maresca, D.</dc:creator>
<dc:creator>Abundo, M. P.</dc:creator>
<dc:creator>Mittelstein, D. R.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2019-07-06</dc:date>
<dc:identifier>doi:10.1101/691105</dc:identifier>
<dc:title><![CDATA[Genetically encoded nanostructures enable acoustic manipulation of engineered cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-07-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/694448v1?rss=1">
<title>
<![CDATA[
Modular Thermal Control of Protein Dimerization 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/694448v1?rss=1</link>
<description><![CDATA[
Protein-protein interactions and protein localization are essential mechanisms of cellular signal transduction. The ability to externally control such interactions using chemical and optogenetic methods has facilitated biological research and provided components for the engineering of cell-based therapies and materials. However, chemical and optical methods are limited in their ability to provide spatiotemporal specificity in light-scattering tissues. To overcome these limitations, we present "thermomers," modular protein dimerization domains controlled with temperature - a form of energy that can be delivered to cells both globally and locally in a wide variety of in vitro and in vivo contexts. Thermomers are based on a sharply thermolabile coiled-coil protein, which we engineered to heterodimerize at a tunable transition temperature within the biocompatible range of 37-42 {degrees}C. When fused to other proteins, thermomers can reversibly control their association, as demonstrated via membrane localization in mammalian cells. This technology enables remote control of intracellular protein-protein interactions with a form of energy that can be delivered with spatiotemporal precision in a wide range of biological, therapeutic and living material scenarios.
]]></description>
<dc:creator>Piraner, D. I.</dc:creator>
<dc:creator>Wu, Y.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2019-07-13</dc:date>
<dc:identifier>doi:10.1101/694448</dc:identifier>
<dc:title><![CDATA[Modular Thermal Control of Protein Dimerization]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-07-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/701680v1?rss=1">
<title>
<![CDATA[
Giotto, a pipeline for integrative analysis and visualization of single-cell spatial transcriptomic data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/701680v1?rss=1</link>
<description><![CDATA[
The rapid development of novel spatial transcriptomic and proteomic technologies has provided new opportunities to investigate the interactions between cells and their native microenvironment. However, effective use of such technologies requires the development of innovative computational tools that are easily accessible and intuitive to use. Here we present Giotto, a comprehensive, flexible, robust, and open-source toolbox for spatial transcriptomic and proteomic data analysis and visualization. The data analysis module provides end-to-end analysis by implementing a wide range of algorithms for characterizing cell-type distribution, spatially coherent gene expression patterns, and interactions between each cell and its surrounding neighbors. Furthermore, Giotto can also be used in conjunction with external single-cell RNAseq data to infer the spatial enrichment of cell types from data that do not have single-cell resolution. The data visualization module allows users to interactively visualize the gene expression data, analysis outputs, and additional imaging features, thereby providing a user-friendly workspace to explore multiple modalities of information for biological investigation. These two modules can be used iteratively for refined analysis and hypothesis development. We applied Giotto to a wide range of public datasets encompassing diverse technologies and platforms, thereby demonstrating its general applicability for spatial transcriptomic and proteomic data analysis and visualization.
]]></description>
<dc:creator>Dries, R.</dc:creator>
<dc:creator>Zhu, Q.</dc:creator>
<dc:creator>Eng, C.-H. L.</dc:creator>
<dc:creator>Sarkar, A.</dc:creator>
<dc:creator>Bao, F.</dc:creator>
<dc:creator>George, R. E.</dc:creator>
<dc:creator>Pierson, N.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:creator>Yuan, G.-C.</dc:creator>
<dc:date>2019-07-13</dc:date>
<dc:identifier>doi:10.1101/701680</dc:identifier>
<dc:title><![CDATA[Giotto, a pipeline for integrative analysis and visualization of single-cell spatial transcriptomic data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-07-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/706606v1?rss=1">
<title>
<![CDATA[
MATE-Seq: Microfluidic Antigen-TCR Engagement Sequencing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/706606v1?rss=1</link>
<description><![CDATA[
Adaptive immunity is based on peptide antigen recognition. Our ability to harness the immune system for therapeutic gain relies on the discovery of the T cell receptor (TCR) genes that selectively target antigens from infections, mutated proteins, and foreign agents. Here we present a method that selectively labels peptide antigen-specific CD8+ T-cells in human blood using magnetic nanoparticles functionalized with peptide-MHC tetramers, isolates these specific cells within an integrated microfluidic device, and directly amplifies the TCR genes for sequencing. Critically, the identity of the peptide recognized by the TCR is preserved, providing the link between peptide and gene. The platform requires inputs on the order of just 100,000 CD8+ T cells, can be multiplexed for simultaneous analysis of multiple peptides, and performs sorting and isolation on chip. We demonstrate 1000-fold sensitivity enhancement of antigen-specific T-cell receptor detection and simultaneous capture of two virus antigen-specific T-cell receptors from samples of human blood.
]]></description>
<dc:creator>Ng, A. H.</dc:creator>
<dc:creator>Peng, S.</dc:creator>
<dc:creator>Xu, A. M.</dc:creator>
<dc:creator>Noh, W. J.</dc:creator>
<dc:creator>Guo, K.</dc:creator>
<dc:creator>Bethune, M. T.</dc:creator>
<dc:creator>Chour, W.</dc:creator>
<dc:creator>Choi, J.</dc:creator>
<dc:creator>Yang, S.</dc:creator>
<dc:creator>Baltimore, D.</dc:creator>
<dc:creator>Heath, J. R.</dc:creator>
<dc:date>2019-07-18</dc:date>
<dc:identifier>doi:10.1101/706606</dc:identifier>
<dc:title><![CDATA[MATE-Seq: Microfluidic Antigen-TCR Engagement Sequencing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-07-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/710327v1?rss=1">
<title>
<![CDATA[
Deep Multi-State Dynamic Recurrent Neural Networks Operating on Wavelet Based Neural Features for Robust Brain Machine Interfaces 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/710327v1?rss=1</link>
<description><![CDATA[
We present a new deep multi-state Dynamic Recurrent Neural Network (DRNN) architecture for Brain Machine Interface (BMI) applications. Our DRNN is used to predict Cartesian representation of a computer cursor movement kinematics from open-loop neural data recorded from the posterior parietal cortex (PPC) of a human subject in a BMI system. We design the algorithm to achieve a reasonable trade-off between performance and robustness, and we constrain memory usage in favor of future hardware implementation. We feed the predictions of the network back to the input to improve prediction performance and robustness. We apply a scheduled sampling approach to the model in order to solve a statistical distribution mismatch between the ground truth and predictions. Additionally, we configure a small DRNN to operate with a short history of input, reducing the required buffering of input data and number of memory accesses. This configuration lowers the expected power consumption in a neural network accelerator. Operating on wavelet-based neural features, we show that the average performance of DRNN surpasses other state-of-the-art methods in the literature on both single- and multi-day data recorded over 43 days. Results show that multi-state DRNN has the potential to model the nonlinear relationships between the neural data and kinematics for robust BMIs.
]]></description>
<dc:creator>Haghi, B.</dc:creator>
<dc:creator>Kellis, S.</dc:creator>
<dc:creator>Shah, S.</dc:creator>
<dc:creator>Ashok, M.</dc:creator>
<dc:creator>Bashford, L.</dc:creator>
<dc:creator>Kramer, D.</dc:creator>
<dc:creator>Lee, B.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:creator>Emami, A.</dc:creator>
<dc:date>2019-07-22</dc:date>
<dc:identifier>doi:10.1101/710327</dc:identifier>
<dc:title><![CDATA[Deep Multi-State Dynamic Recurrent Neural Networks Operating on Wavelet Based Neural Features for Robust Brain Machine Interfaces]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-07-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/713420v1?rss=1">
<title>
<![CDATA[
Visual search mimics configural processing in human causal learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/713420v1?rss=1</link>
<description><![CDATA[
Theories of learning distinguish between elemental and configural stimulus processing depending on whether stimuli are processed independently or as whole configurations. Evidence for elemental processing comes from findings of summation in animals where a compound of two dissimilar stimuli is deemed to be more predictive than each stimulus alone, whereas configural processing is supported by experiments employing similar stimuli in which summation is not found. However, in humans the summation effect is robust and impervious to similarity manipulations. In three experiments in human predictive learning, we show that summation can be obliterated when partially reinforced cues are added to the summands in training and test. This lack of summation only holds when the partially reinforced cues are similar to the reinforced cues (Experiment 1) and seems to depend on participants sampling only the most salient cue in each trial (Experiments 2a and 2b) in a sequential visual search process. Instead of attributing our and others instances of lack of summation to the customary idea of configural processing, we offer a formal sub-sampling rule that might be applied to situations in which the stimuli are hard to parse from each other.
]]></description>
<dc:creator>Perez, O. D.</dc:creator>
<dc:creator>Narasiwodeyar, S.</dc:creator>
<dc:creator>Soto, F. A.</dc:creator>
<dc:date>2019-07-24</dc:date>
<dc:identifier>doi:10.1101/713420</dc:identifier>
<dc:title><![CDATA[Visual search mimics configural processing in human causal learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-07-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/719278v1?rss=1">
<title>
<![CDATA[
Modeling predicts that CRISPR-based activators, unlike CRISPR-based repressors, scale well with increasing gRNA competition and dCas9 bottlenecking 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/719278v1?rss=1</link>
<description><![CDATA[
Synthetic transcriptional networks built from CRISPR-based repressors (CRISPRi) rely on shared use of a core dCas9 protein. In E. coli, CRISPRi cannot support more than about a dozen simultaneous gRNAs before the fold repression of any individual gRNA drops below 10x. We show with a simple model based on previous characterization of competition in CRISPRi that activation by CRISPR-based activators (CRISPRa) is much less sensitive to dCas9 bottle-necking than CRISPRi. We predict that E. coli should be able to support dozens to hundreds of CRISPRa gRNAs at >10-fold activation.
]]></description>
<dc:creator>Clamons, S.</dc:creator>
<dc:creator>Murray, R.</dc:creator>
<dc:date>2019-07-30</dc:date>
<dc:identifier>doi:10.1101/719278</dc:identifier>
<dc:title><![CDATA[Modeling predicts that CRISPR-based activators, unlike CRISPR-based repressors, scale well with increasing gRNA competition and dCas9 bottlenecking]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-07-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/720920v1?rss=1">
<title>
<![CDATA[
Myogenesis modelled by human pluripotent stem cells uncovers Duchenne muscular dystrophy phenotypes prior to skeletal muscle commitment 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/720920v1?rss=1</link>
<description><![CDATA[
Duchenne muscular dystrophy (DMD) causes severe disability of children and death of young men, with an incidence of approximately 1/5,000 male births. Symptoms appear in early childhood, with a diagnosis made around 4 years old, a time where the amount of muscle damage is already significant, preventing early therapeutic interventions that could be more efficient at halting disease progression. In the meantime, the precise moment at which disease phenotypes arise - even asymptomatically - is still unknown. Thus, there is a critical need to better define DMD onset as well as its first manifestations, which could help identify early disease biomarkers and novel therapeutic targets.

In this study, we have used human induced pluripotent stem cells (hiPSCs) from DMD patients to model skeletal myogenesis, and compared their differentiation dynamics to that of healthy control cells by a comprehensive multi-omic analysis. Transcriptome and miRnome comparisons combined with protein analyses at 7 time points demonstrated that hiPSC differentiation 1) mimics described DMD phenotypes at the differentiation endpoint; and 2) homogeneously and robustly recapitulates key developmental steps - mesoderm, somite, skeletal muscle - which offers the possibility to explore dystrophin functions and find earlier disease biomarkers.

Starting at the somite stage, mitochondrial gene dysregulations escalate during differentiation. We also describe fibrosis as an intrinsic feature of skeletal muscle cells that starts early during myogenesis. In sum, our data strongly argue for an early developmental manifestation of DMD whose onset is triggered before the entry into the skeletal muscle compartment, data leading to a necessary reconsideration of dystrophin functions during muscle development.
]]></description>
<dc:creator>Mournetas, V.</dc:creator>
<dc:creator>Massourides, E.</dc:creator>
<dc:creator>Dupont, J.-B.</dc:creator>
<dc:creator>Kornobis, E.</dc:creator>
<dc:creator>Polveche, H.</dc:creator>
<dc:creator>Jarrige, M.</dc:creator>
<dc:creator>Gosselin, M.</dc:creator>
<dc:creator>Garbis, S. D.</dc:creator>
<dc:creator>Gorecki, D. C.</dc:creator>
<dc:creator>Pinset, C.</dc:creator>
<dc:date>2019-08-04</dc:date>
<dc:identifier>doi:10.1101/720920</dc:identifier>
<dc:title><![CDATA[Myogenesis modelled by human pluripotent stem cells uncovers Duchenne muscular dystrophy phenotypes prior to skeletal muscle commitment]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-08-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/724740v1?rss=1">
<title>
<![CDATA[
Kinetic Inference Resolves Epigenetic Mechanism of Drug Resistance in Melanoma 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/724740v1?rss=1</link>
<description><![CDATA[
Drug-induced dedifferentiation towards a drug-tolerant persister state is a common mechanism cancer cells exploit to escape therapies, posing a significant obstacle to sustained therapeutic efficacy. The dynamic coordination of epigenomic and transcriptomic programs at the early-stage of drug exposure, which initiates and orchestrates these reversible dedifferentiation events, remains largely unexplored. Here we employ high-temporal-resolution multi-omics profiling, information-theoretic approaches, and dynamic system modeling to probe these processes in BRAF-mutant melanoma models and patient specimens. We uncover a hysteretic transition trajectory of melanoma cells in response to oncogene inhibition and subsequent release, driven by the sequential operation of two tightly coupled transcriptional waves, which orchestrate genome-scale chromatin state reconfiguration. Modeling of the transcriptional wave interactions predicts NF-{kappa}B/RelA-driven chromatin remodeling as the underlying mechanism of cell-state dedifferentiation, a finding we validate experimentally. Our results identify critical RelA-target genes that are epigenetically modulated to drive this process, establishing a quantitative epigenome gauge to measure cell-state plasticity in melanomas, which supports the potential use of drugs targeting epigenetic machineries to potentiate oncogene inhibition. Extending our investigation to other cancer models, we identify oxidative stress-mediated NF-{kappa}B/RelA activation as a common mechanism driving cellular transitions towards drug-tolerant persister states, revealing a novel and pivotal role for the NF-{kappa}B signaling axis in linking cellular oxidative stress to cancer progression.
]]></description>
<dc:creator>Su, Y.</dc:creator>
<dc:creator>Lu, X.</dc:creator>
<dc:creator>Li, G.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Kong, Y.</dc:creator>
<dc:creator>Lee, J.</dc:creator>
<dc:creator>Ng, R.</dc:creator>
<dc:creator>Wong, S.</dc:creator>
<dc:creator>Robert, L.</dc:creator>
<dc:creator>Warden, C.</dc:creator>
<dc:creator>Liu, V.</dc:creator>
<dc:creator>Chen, J.</dc:creator>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>Yapeng, Y.</dc:creator>
<dc:creator>Cheng, H.</dc:creator>
<dc:creator>Ng, A.</dc:creator>
<dc:creator>Qin, G.</dc:creator>
<dc:creator>Peng, S.</dc:creator>
<dc:creator>Xue, M.</dc:creator>
<dc:creator>Johnson, D.</dc:creator>
<dc:creator>Xu, Y.</dc:creator>
<dc:creator>Wang, J.</dc:creator>
<dc:creator>Wu, X.</dc:creator>
<dc:creator>Shmulevich, I.</dc:creator>
<dc:creator>Shi, Q.</dc:creator>
<dc:creator>Levine, R.</dc:creator>
<dc:creator>Ribas, A.</dc:creator>
<dc:creator>Baltimore, D.</dc:creator>
<dc:creator>Guo, J.</dc:creator>
<dc:creator>Heath, J. R.</dc:creator>
<dc:creator>Wei, W.</dc:creator>
<dc:date>2019-08-05</dc:date>
<dc:identifier>doi:10.1101/724740</dc:identifier>
<dc:title><![CDATA[Kinetic Inference Resolves Epigenetic Mechanism of Drug Resistance in Melanoma]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-08-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/734939v1?rss=1">
<title>
<![CDATA[
Acoustic biomolecules enhance hemodynamic functional ultrasound imaging of neural activity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/734939v1?rss=1</link>
<description><![CDATA[
Hemodynamic functional ultrasound imaging (fUS) of neural activity provides a unique combination of spatial coverage, spatiotemporal resolution and compatibility with freely moving animals. However, deep and transcranial monitoring of brain activity and the imaging of dynamics in slow-flowing blood vessels remains challenging. To enhance fUS capabilities, we introduce biomolecular hemodynamic enhancers based on gas vesicles (GVs), genetically encodable ultrasound contrast agents derived from buoyant photosynthetic microorganisms. We show that intravenously infused GVs enhance ultrafast Doppler ultrasound contrast and visually-evoked hemodynamic contrast in transcranial fUS of the mouse brain. This hemodynamic contrast enhancement is smoother than that provided by conventional microbubbles, allowing GVs to more reliably amplify neuroimaging signals.
]]></description>
<dc:creator>Maresca, D.</dc:creator>
<dc:creator>Payen, T.</dc:creator>
<dc:creator>Lee-Gosselin, A.</dc:creator>
<dc:creator>Ling, B.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Demene, C.</dc:creator>
<dc:creator>Tanter, M.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2019-08-15</dc:date>
<dc:identifier>doi:10.1101/734939</dc:identifier>
<dc:title><![CDATA[Acoustic biomolecules enhance hemodynamic functional ultrasound imaging of neural activity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-08-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/735985v1?rss=1">
<title>
<![CDATA[
NEURONS THAT FUNCTION WITHIN AN INTEGRATOR TO PROMOTE A PERSISTENT BEHAVIORAL STATE IN DROSOPHILA 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/735985v1?rss=1</link>
<description><![CDATA[
Innate behaviors involve both reflexive motor programs and internal states. In Drosophila, optogenetic activation of male-specific P1 interneurons triggers courtship song, as well as a persistent behavioral state that prolongs courtship and enhances aggressiveness. Here we identify pCd neurons as persistently activated by repeated P1 stimulation. pCd neurons are required for P1-evoked persistent courtship and aggression, as well as for normal social behavior. Activation of pCd neurons alone is inefficacious, but enhances and prolongs courtship or aggression promoted by female cues. Transient female exposure induced persistent increases in male aggressiveness, an effect suppressed by transiently silencing pCd neurons. Transient silencing of pCd also disrupted P1-induced persistent physiological activity, implying a requisite role in persistence. Finally, P1 activation of pCd neurons enhanced their responsiveness to cVA, an aggression-promoting pheromone. Thus, pCd neurons function within a circuit that integrates P1 input, to promote a persistent internal state that enhances multiple social behaviors.
]]></description>
<dc:creator>Jung, Y.</dc:creator>
<dc:creator>Kennedy, A.</dc:creator>
<dc:creator>Chiu, H.</dc:creator>
<dc:creator>Mohammad, F.</dc:creator>
<dc:creator>Claridge-Chang, A.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:date>2019-08-15</dc:date>
<dc:identifier>doi:10.1101/735985</dc:identifier>
<dc:title><![CDATA[NEURONS THAT FUNCTION WITHIN AN INTEGRATOR TO PROMOTE A PERSISTENT BEHAVIORAL STATE IN DROSOPHILA]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-08-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/737189v1?rss=1">
<title>
<![CDATA[
Simulations of proposed mechanisms of FtsZ-driven cell constriction 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/737189v1?rss=1</link>
<description><![CDATA[
To divide, bacteria must constrict their membranes against significant force from turgor pressure. A tubulin homo-log, FtsZ, is thought to drive constriction, but how FtsZ filaments might generate constrictive force in the absence of motor proteins is not well understood. There are two predominant models in the field. In one, filaments overlap to form complete rings around the circumference of the cell; as filaments slide against each other to maximize lateral contact, the rings constrict. In the other, filaments exert force on the membrane by a GTP-hydrolysis-induced switch in conformation from straight to bent. Here we developed software, ZCONSTRICT, for quantitative 3D simulations of Gram-negative bacterial cell division to test these two models and identify critical conditions required for them to work. We find that the avidity of lateral interactions quickly halts the sliding of filaments, so a mechanism such as depolymerization or treadmilling is required to sustain constriction by filament sliding. For filament bending, we find that a mechanism such as the presence of a rigid linker is required to constrain bending within the division plane and maintain the distance observed in vivo between the filaments and the membrane. We also explored the recent observation of constriction associated with a single FtsZ filament and found that it can be explained by the filament bending model if there is a rigid connection between the filament and the cell wall. Together, our work sheds light on the physical principles underlying bacterial cell division and informs future experiments to elucidate the mechanism of FtsZ.
]]></description>
<dc:creator>Nguyen, L. T.</dc:creator>
<dc:creator>Oikonomou, C. M.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2019-08-15</dc:date>
<dc:identifier>doi:10.1101/737189</dc:identifier>
<dc:title><![CDATA[Simulations of proposed mechanisms of FtsZ-driven cell constriction]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-08-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/737601v1?rss=1">
<title>
<![CDATA[
Interpretable factor models of single-cell RNA-seq via variational autoencoders 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/737601v1?rss=1</link>
<description><![CDATA[
Single cell RNA-seq makes possible the investigation of variability in gene expression among cells, and dependence of variation on cell type. Statistical inference methods for such analyses must be scalable, and ideally interpretable. We present an approach based on a modification of a recently published highly scalable variational autoencoder framework that provides interpretability without sacrificing much accuracy. We demonstrate that our approach enables identification of gene programs in massive datasets. Our strategy, namely the learning of factor models with the auto-encoding variational Bayes framework, is not domain specific and may be of interest for other applications.
]]></description>
<dc:creator>Svensson, V.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2019-08-16</dc:date>
<dc:identifier>doi:10.1101/737601</dc:identifier>
<dc:title><![CDATA[Interpretable factor models of single-cell RNA-seq via variational autoencoders]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-08-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/739474v1?rss=1">
<title>
<![CDATA[
SVFX: a machine-learning framework to quantify the pathogenicity of structural variants 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/739474v1?rss=1</link>
<description><![CDATA[
A rapid decline in sequencing cost has made large-scale genome sequencing studies feasible. One of the fundamental goals of these studies is to catalog all pathogenic variants. Numerous methods and tools have been developed to interpret point mutations and small insertions and deletions. However, there is a lack of approaches for identifying pathogenic genomic structural variations (SVs). That said, SVs are known to play a crucial role in many diseases by altering the sequence and three-dimensional structure of the genome. Previous studies have suggested a complex interplay of genomic and epigenomic features in the emergence and distribution of SVs. However, the exact mechanism of pathogenesis for SVs in different diseases is not straightforward to decipher. Thus, we built an agnostic machine-learning-based workflow, called SVFX, to assign a "pathogenicity score" to somatic and germline SVs in various diseases. In particular, we generated somatic and germline training models, which included genomic, epigenomic, and conservation-based features for SV call sets in diseased and healthy individuals. We then applied SVFX to SVs in six different cancer cohorts and a cardiovascular disease (CVD) cohort. Overall, SVFX achieved high accuracy in identifying pathogenic SVs. Moreover, we found that predicted pathogenic SVs in cancer cohorts were enriched among known cancer genes and many cancer-related pathways (including Wnt signaling, Ras signaling, DNA repair, and ubiquitin-mediated proteolysis). Finally, we note that SVFX is flexible and can be easily extended to identify pathogenic SVs in additional disease cohorts.
]]></description>
<dc:creator>kumar, s.</dc:creator>
<dc:creator>Harmanci, A.</dc:creator>
<dc:creator>Vytheeswaran, J.</dc:creator>
<dc:creator>Gerstein, M.</dc:creator>
<dc:date>2019-08-19</dc:date>
<dc:identifier>doi:10.1101/739474</dc:identifier>
<dc:title><![CDATA[SVFX: a machine-learning framework to quantify the pathogenicity of structural variants]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-08-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/742304v1?rss=1">
<title>
<![CDATA[
A curated database reveals trends in single cell transcriptomics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/742304v1?rss=1</link>
<description><![CDATA[
The more than 500 single-cell transcriptomics studies that have been published to date constitute a valuable and vast resource for biological discovery. While various "atlas" projects have collated some of the associated datasets, most questions related to specific tissue types, species, or other attributes of studies require identifying papers through manual and challenging literature search. To facilitate discovery with published single-cell transcriptomics data, we have assembled a near exhaustive, manually curated database of single-cell transcriptomics studies with key information: descriptions of the type of data and technologies used, along with descriptors of the biological systems studied. Additionally, the database contains summarized information about analysis in the papers, allowing for analysis of trends in the field. As an example, we show that the number of cell types identified in scRNA-seq studies is proportional to the number of cells analysed. The database is available at www.nxn.se/single-cell-studies/gui.
]]></description>
<dc:creator>Svensson, V.</dc:creator>
<dc:creator>da Veiga Beltrame, E.</dc:creator>
<dc:date>2019-08-21</dc:date>
<dc:identifier>doi:10.1101/742304</dc:identifier>
<dc:title><![CDATA[A curated database reveals trends in single cell transcriptomics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-08-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/745117v1?rss=1">
<title>
<![CDATA[
Interdimer zipping in the chemoreceptor signaling domain revealed by molecular dynamics simulations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/745117v1?rss=1</link>
<description><![CDATA[
Chemoreceptors are principal components of the bacterial sensory system that modulates cellular motility. They detect changes in the environment and transmit information to CheA histidine kinase, which ultimately controls cellular flagellar motors. The prototypical Tsr chemoreceptor in E. coli is a homodimer containing two principal functional modules: (i) a periplasmic ligand-binding domain and (ii) a cytoplasmic signaling domain. Chemoreceptor dimers are arranged into a trimer of dimers at the tip of the signaling domain comprising a minimal physical unit essential for enhancing the CheA activity several hundredfold. Trimers of dimers are arranged into highly ordered hexagon arrays at the cell pole; however, the mechanism underlying the trimer-of-dimer and higher order array formation remains unclear. Furthermore, molecular mechanisms of signal transduction that are likely to involve inter-dimer interactions are not fully understood. Here we apply all-atom, microsecond-time scale molecular dynamics simulations of the Tsr trimer of dimers atomic model in order to obtain further insight into potential interactions within the chemoreceptor signaling unit. We show extensive interactions between homodimers at the hairpin tip of the signaling domain, where strong hydrophobic interactions maintain binding. A subsequent zipping of homodimers is facilitated by electrostatic interactions, in particular by polar solvation energy and salt bridges that stabilize the final compact structure, which extends beyond the kinase interacting subdomain. Our study provides evidence that interdimer interactions within the chemoreceptor signaling domain are more complex than previously thought.
]]></description>
<dc:creator>Petukh, M. G.</dc:creator>
<dc:creator>Ortega, D. R.</dc:creator>
<dc:creator>Baudry, J.</dc:creator>
<dc:creator>Zhulin, I. B.</dc:creator>
<dc:date>2019-08-22</dc:date>
<dc:identifier>doi:10.1101/745117</dc:identifier>
<dc:title><![CDATA[Interdimer zipping in the chemoreceptor signaling domain revealed by molecular dynamics simulations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-08-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/762773v1?rss=1">
<title>
<![CDATA[
Quantifying the tradeoff between sequencing depth and cell number in single-cell RNA-seq 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/762773v1?rss=1</link>
<description><![CDATA[
The allocation of a sequencing budget when designing single cell RNA-seq experiments requires consideration of the tradeoff between number of cells sequenced and the read depth per cell. One approach to the problem is to perform a power analysis for a univariate objective such as differential expression. However, many of the goals of single-cell analysis requires consideration of the multivariate structure of gene expression, such as clustering. We introduce an approach to quantifying the impact of sequencing depth and cell number on the estimation of a multivariate generative model for gene expression that is based on error analysis in the framework of a variational autoencoder. We find that at shallow depths, the marginal benefit of deeper sequencing per cell significantly outweighs the benefit of increased cell numbers. Above about 15,000 reads per cell the benefit of increased sequencing depth is minor. Code for the workflow reproducing the results of the paper is available at https://github.com/pachterlab/SBP_2019/.
]]></description>
<dc:creator>Svensson, V.</dc:creator>
<dc:creator>da Veiga Beltrame, E.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2019-09-09</dc:date>
<dc:identifier>doi:10.1101/762773</dc:identifier>
<dc:title><![CDATA[Quantifying the tradeoff between sequencing depth and cell number in single-cell RNA-seq]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-09-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/767061v1?rss=1">
<title>
<![CDATA[
Comparing serial X-ray crystallography and microcrystal electron diffraction (MicroED) as methods for routine structure determination from small macromolecular crystals 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/767061v1?rss=1</link>
<description><![CDATA[
Innovative new crystallographic methods are facilitating structural studies from ever smaller crystals of biological macromolecules. In particular, serial X-ray crystallography and microcrystal electron diffraction (MicroED) have emerged as useful methods for obtaining structural information from crystals on the nanometer to micron scale. Despite the utility of these methods, their implementation can often be difficult, as they present many challenges not encountered in traditional macromolecular crystallography experiments. Here, we describe XFEL serial crystallography experiments and MicroED experiments using batch-grown microcrystals of the enzyme cyclophilin A (CypA). Our results provide a roadmap for researchers hoping to design macromolecular microcrystallography experiments, and they highlight the strengths and weaknesses of the two methods. Specifically, we focus on how the different physical conditions imposed by the sample preparation and delivery methods required for each type of experiment effect the crystal structure of the enzyme.
]]></description>
<dc:creator>Wolff, A. M.</dc:creator>
<dc:creator>Young, I. D.</dc:creator>
<dc:creator>Sierra, R. G.</dc:creator>
<dc:creator>Brewster, A. S.</dc:creator>
<dc:creator>Martynowycz, M. W.</dc:creator>
<dc:creator>Nango, E.</dc:creator>
<dc:creator>Sugahara, M.</dc:creator>
<dc:creator>Nakane, T.</dc:creator>
<dc:creator>Ito, K.</dc:creator>
<dc:creator>Aquila, A.</dc:creator>
<dc:creator>Bhowmick, A.</dc:creator>
<dc:creator>Biel, J. T.</dc:creator>
<dc:creator>Carbajo, S.</dc:creator>
<dc:creator>Cohen, A. E.</dc:creator>
<dc:creator>Cortez, S.</dc:creator>
<dc:creator>Gonzalez, A.</dc:creator>
<dc:creator>Hino, T.</dc:creator>
<dc:creator>Im, D.</dc:creator>
<dc:creator>Koralek, J. D.</dc:creator>
<dc:creator>Kubo, M.</dc:creator>
<dc:creator>Lazarou, T. S.</dc:creator>
<dc:creator>Nomura, T.</dc:creator>
<dc:creator>Owada, S.</dc:creator>
<dc:creator>Samelson, A.</dc:creator>
<dc:creator>Tanaka, R.</dc:creator>
<dc:creator>Tanaka, T.</dc:creator>
<dc:creator>Thompson, E. M.</dc:creator>
<dc:creator>van den Bedem, H.</dc:creator>
<dc:creator>Woldeyes, R. A.</dc:creator>
<dc:creator>Yumoto, F.</dc:creator>
<dc:creator>Zhao, W.</dc:creator>
<dc:creator>Tono, K.</dc:creator>
<dc:creator>Boutet, S.</dc:creator>
<dc:creator>Iwata, S.</dc:creator>
<dc:creator>Gonen, T.</dc:creator>
<dc:creator>Sauter, N. K.</dc:creator>
<dc:creator>Fraser, J. S.</dc:creator>
<dc:creator>Thompson, M. C.</dc:creator>
<dc:date>2019-09-12</dc:date>
<dc:identifier>doi:10.1101/767061</dc:identifier>
<dc:title><![CDATA[Comparing serial X-ray crystallography and microcrystal electron diffraction (MicroED) as methods for routine structure determination from small macromolecular crystals]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-09-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/768341v1?rss=1">
<title>
<![CDATA[
TRAF6 controls excitatory spinogenesis and excitation-inhibition balance thought binding neuroplastin 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/768341v1?rss=1</link>
<description><![CDATA[
Synaptogenic mechanisms and their relevance to achieve a correct synapse density and activity in mature neurons are poorly understood. Here, we show that the tumor necrosis factor receptor-associated factor 6 (TRAF6) controls early spinogenesis by binding the cell adhesion molecule neuroplastin which is has been related to synapse formation in vivo. TRAF6-neuroplastin co-precipitations from brain samples and co-transfected HEK cells is explained by direct interaction of the proteins based on three-dimensional modelling and biochemical identification of intracellular amino acids of neuroplastin binding the TRAF-C domain of TRAF6 with micromolar affinity. TRAF6 was not only required for normal spinogenesis but also was strictly necessary to restore failed spinogenesis in neuroplastin-deficient neurons. Independently from neuroplastins extracellular adhesive properties or interaction with another known partner i.e. the plasma membrane Ca2+ ATPases, TRAF6 mediated formation of new postsynapses by neuroplastin overexpression in rat hippocampal neurons. Furthermore, TRAF6-controlled spinogenesis was required for the establishment of a correct synapse density as well as proper synaptic activity and intrinsic neuronal activity as demonstrated with intracellular and extracellular electrophysiological recordings. These findings provide a novel mechanism for early synapse formation that shapes connectivity and functioning of hippocampal neurons.
]]></description>
<dc:creator>Kumar Vemula, S.</dc:creator>
<dc:creator>Malci, A.</dc:creator>
<dc:creator>Junge, L.</dc:creator>
<dc:creator>Lehmann, A.-C.</dc:creator>
<dc:creator>Rama, R.</dc:creator>
<dc:creator>Hradsky, J.</dc:creator>
<dc:creator>Matute, R. A.</dc:creator>
<dc:creator>Naumann, M.</dc:creator>
<dc:creator>Kreutz, M. R.</dc:creator>
<dc:creator>Seidenbecher, C. I.</dc:creator>
<dc:creator>Gundelfinger, E. D.</dc:creator>
<dc:creator>Herrera-Molina, R.</dc:creator>
<dc:date>2019-09-14</dc:date>
<dc:identifier>doi:10.1101/768341</dc:identifier>
<dc:title><![CDATA[TRAF6 controls excitatory spinogenesis and excitation-inhibition balance thought binding neuroplastin]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-09-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/779124v1?rss=1">
<title>
<![CDATA[
Selective Ablation of Cancer Cells with Low Intensity Pulsed Ultrasound 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/779124v1?rss=1</link>
<description><![CDATA[
Ultrasound can be focused into deep tissues with millimeter precision to perform non-invasive ablative therapy for diseases such as cancer. In most cases, this ablation uses high intensity ultrasound to deposit non-selective thermal or mechanical energy at the ultrasound focus, damaging both healthy bystander tissue and cancer cells. Here we describe an alternative low intensity pulsed ultrasound approach that leverages the distinct mechanical properties of neoplastic cells to achieve inherent cancer selectivity. We show that when applied at a specific frequency and pulse duration, focused ultrasound selectively disrupts a panel of breast, colon, and leukemia cancer cell models in suspension without significantly damaging healthy immune or red blood cells. Mechanistic experiments reveal that the formation of acoustic standing waves and the emergence of cell-seeded cavitation lead to cytoskeletal disruption, expression of apoptotic markers, and cell death. The inherent selectivity of this low intensity pulsed ultrasound approach offers a potentially safer and thus more broadly applicable alternative to non-selective high intensity ultrasound ablation.
]]></description>
<dc:creator>Mittelstein, D. R.</dc:creator>
<dc:creator>Ye, J.</dc:creator>
<dc:creator>Schibber, E. F.</dc:creator>
<dc:creator>Roychoudhury, A.</dc:creator>
<dc:creator>Troyas, S. L.</dc:creator>
<dc:creator>Fekrazad, M. H.</dc:creator>
<dc:creator>Ortiz, M.</dc:creator>
<dc:creator>Lee, P. P.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Gharib, M.</dc:creator>
<dc:date>2019-10-01</dc:date>
<dc:identifier>doi:10.1101/779124</dc:identifier>
<dc:title><![CDATA[Selective Ablation of Cancer Cells with Low Intensity Pulsed Ultrasound]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/783191v1?rss=1">
<title>
<![CDATA[
Learning with naturalistic odor representations in a dynamic model of the Drosophila olfactory system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/783191v1?rss=1</link>
<description><![CDATA[
Many odor receptors in the insect olfactory system are broadly tuned, yet insects can form associative memories that are odor-specific. The key site of associative olfactory learning in insects, the mushroom body, contains a population of Kenyon Cells (KCs) that form sparse representations of odor identity and enable associative learning of odors by mushroom body output neurons (MBONs). This architecture is well suited to odor-specific associative learning if KC responses to odors are uncorrelated with each other, however it is unclear whether this hold for actual KC representations of natural odors. We introduce a dynamic model of the Drosophila olfactory system that predicts the responses of KCs to a panel of 110 natural and monomolecular odors, and examine the generalization properties of associative learning in model MBONs. While model KC representations of odors are often quite correlated, we identify mechanisms by which odor-specific associative learning is still possible.
]]></description>
<dc:creator>Kennedy, A.</dc:creator>
<dc:date>2019-09-26</dc:date>
<dc:identifier>doi:10.1101/783191</dc:identifier>
<dc:title><![CDATA[Learning with naturalistic odor representations in a dynamic model of the Drosophila olfactory system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-09-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/784595v1?rss=1">
<title>
<![CDATA[
Cytoskeletal organization in isolated plant cells under geometry control. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/784595v1?rss=1</link>
<description><![CDATA[
Specific cell and tissue form is essential to support many biological functions of living organisms. During development, the creation of different shapes at the cellular and tissue level fundamentally requires the integration of genetic, biochemical and physical inputs.nnIt is well established that the cortical microtubule network plays a key role in the morphogenesis of the plant cell wall by guiding the organisation of new cell wall material. Moreover, it has been suggested that light or mechanical stresses can orient the microtubules thereby controlling wall architecture and plant cell shape. The cytoskeleton is thus a major determinant of plant cell shape. What is less clear is how cell shape in turn influences cytoskeletal organization.nnRecent in vitro experiments and numerical simulations predicted that a geometry-based rule is sufficient to explain some of the microtubule organization observed in cells. Due to their high flexural rigidity and persistence length of the order of a few millimeters, MTs are rigid over cellular dimensions and are thus expected to align along their long axis if constrained in specific geometries. This hypothesis remains to be tested in cellulo.nnHere we present an experimental approach to explore the relative contribution of geometry to the final organization of actin and microtubule cytoskeletons in single plant cells. We show that, in cells constrained in rectangular shapes, the cytoskeleton align along the long axis of the cells. By studying actin and microtubules in cells with the same system we show that while actin organisation requires microtubules to be present to align the converse is not the case. A model of self organizing microtubules in 3D predicts that severing of microtubules is an important parameter controlling the anisotropy of the microtubule network. We experimentally confirmed the model predictions by analysing the response to shape change in plant cells with altered microtubule severing dynamics. This work is a first step towards assessing quantitatively how cell geometry contributes to the control of cytoskeletal organization in living plant cells.
]]></description>
<dc:creator>Durand-Smet, P.</dc:creator>
<dc:creator>Spelman, T.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:creator>Jonsson, H.</dc:creator>
<dc:date>2019-09-26</dc:date>
<dc:identifier>doi:10.1101/784595</dc:identifier>
<dc:title><![CDATA[Cytoskeletal organization in isolated plant cells under geometry control.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-09-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/786715v1?rss=1">
<title>
<![CDATA[
Bacterial flagellar motor PL-ring disassembly sub-complexes are widespread and ancient 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/786715v1?rss=1</link>
<description><![CDATA[
The bacterial flagellar motor is an amazing nanomachine. Understanding how such complex structures arose is crucial to our understanding of cellular evolution. We and others recently reported that in several Gammaproteobacterial species, a relic sub-complex comprising the decorated P- and L-rings persists in the outer membrane after flagellum disassembly. Imaging nine additional species with cryo-electron tomography, here we show that this sub-complex persists after flagellum disassembly in other phyla as well. Bioinformatic analyses fail to show evidence of any recent horizontal transfers of the P- and L-ring genes, suggesting that this sub-complex and its persistence is an ancient and conserved feature of the flagellar motor. We hypothesize that one function of the P- and L-rings is to seal the outer membrane after motor disassembly.
]]></description>
<dc:creator>Kaplan, M.</dc:creator>
<dc:creator>Sweredoski, M. J.</dc:creator>
<dc:creator>Rodrigues, J.</dc:creator>
<dc:creator>Tocheva, E. I.</dc:creator>
<dc:creator>Chang, Y.-W.</dc:creator>
<dc:creator>Ortega, D. R.</dc:creator>
<dc:creator>Beeby, M.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2019-09-30</dc:date>
<dc:identifier>doi:10.1101/786715</dc:identifier>
<dc:title><![CDATA[Bacterial flagellar motor PL-ring disassembly sub-complexes are widespread and ancient]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-09-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/790444v1?rss=1">
<title>
<![CDATA[
Cotranslational Folding Stimulates Programmed Ribosomal Frameshifting in the Alphavirus Structural Polyprotein 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/790444v1?rss=1</link>
<description><![CDATA[
Viruses maximize their genetic coding capacity through a variety of biochemical mechanisms including programmed ribosomal frameshifting (PRF), which facilitates the production of multiple proteins from a single transcript. PRF is typically stimulated by structural elements within the mRNA that generate mechanical tension between the transcript and ribosome. However, in this work we show that the forces generated by the cotranslational folding of the nascent polypeptide chain can also enhance PRF. Using an array of biochemical, cellular, and computational techniques, we first demonstrate that the Sindbis virus structural polyprotein forms two competing topological isomers during biosynthesis at the ribosome-translocon complex. We then show that the formation of one of these topological isomers is linked to PRF. Coarse-grained molecular dynamic simulations reveal that the translocon-mediated membrane integration of a transmembrane domain upstream from the ribosomal slip-site generates a force on the nascent polypeptide chain that scales with observed frameshifting. Together, our results demonstrate that cotranslational folding of this protein generates a tension that stimulates PRF. To our knowledge, this constitutes the first example in which the conformational state of the nascent chain has been linked to PRF. These findings raise the possibility that, in addition to RNA-mediated translational recoding, a variety of cotranslational folding and/ or binding events may also stimulate PRF.
]]></description>
<dc:creator>Harrington, H. R.</dc:creator>
<dc:creator>Zimmer, M. H.</dc:creator>
<dc:creator>Chamness, L. M.</dc:creator>
<dc:creator>Nash, V.</dc:creator>
<dc:creator>Penn, W. D.</dc:creator>
<dc:creator>Miller, T. F.</dc:creator>
<dc:creator>Mukhopadhyay, S.</dc:creator>
<dc:creator>Schlebach, J. P.</dc:creator>
<dc:date>2019-10-02</dc:date>
<dc:identifier>doi:10.1101/790444</dc:identifier>
<dc:title><![CDATA[Cotranslational Folding Stimulates Programmed Ribosomal Frameshifting in the Alphavirus Structural Polyprotein]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/791285v1?rss=1">
<title>
<![CDATA[
Micro-scale fluid behavior during cryo-EM sample blotting 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/791285v1?rss=1</link>
<description><![CDATA[
Blotting has been the standard technique for preparing aqueous samples for single-particle electron cryo-microscopy (cryo-EM) for over three decades. This technique removes excess solution from a TEM grid by pressing absorbent filter paper against the specimen prior to vitrification. However, this standard technique produces vitreous ice with inconsistent thickness from specimen to specimen and from region to region within the same specimen, the reasons for which are not understood. Here, high-speed interference-contrast microscopy is used to demonstrate that the irregular pattern of fibers in the filter paper imposes tortuous, highly variable boundaries during removal of excess liquid from a flat, hydrophilic surface. As a result, aqueous films of nonuniform thickness are formed while the filter paper is pressed against the substrate. This pattern of nonuniform liquid thickness changes again after the filter paper is pulled away, but the thickness still does not become completely uniform. We suggest that similar topological features of the liquid film are produced during the standard technique used to blot EM grids and that these manifest in nonuniform ice after vitrification. These observations suggest that alternative thinning techniques, which do not rely on direct contact between the filter paper and the grid, may result in more repeatable and uniform sample thicknesses.nnSTATEMENT OF SIGNIFICANCEMultiple imaging techniques are used to observe dynamic, micro-scale events as excess water is removed from a substrate by blotting with filter paper. As a result, new insight is gained about why the thickness values of remaining sample material are so variable across a single EM grid, as well as from one grid to the next. In addition, quantitative estimates are made of the shear forces to which macromolecular complexes can be exposed during blotting. The fact that sample thicknesses and flow rates are seen to be inherently under poor control during blotting suggests that other methods of removing excess water may be better suited for consistently achieving large sample areas that are suitable for use in electron cryo-microscopy.
]]></description>
<dc:creator>Armstrong, M.</dc:creator>
<dc:creator>Han, B.-G.</dc:creator>
<dc:creator>Gomez, S.</dc:creator>
<dc:creator>Turner, J.</dc:creator>
<dc:creator>Fletcher, D. A.</dc:creator>
<dc:creator>Glaeser, R. M.</dc:creator>
<dc:date>2019-10-02</dc:date>
<dc:identifier>doi:10.1101/791285</dc:identifier>
<dc:title><![CDATA[Micro-scale fluid behavior during cryo-EM sample blotting]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/791954v1?rss=1">
<title>
<![CDATA[
Sequence-Dependent Dynamics of Synthetic and Endogenous RSSs in V(D)J Recombination 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/791954v1?rss=1</link>
<description><![CDATA[
Developing lymphocytes in the immune system of jawed vertebrates assemble antigen-receptor genes by undergoing large-scale reorganization of spatially separated V, D, and J gene segments through a process known as V(D)J recombination. The RAG protein initiates this process by binding and cutting recombination signal sequences (RSSs) composed of conserved heptamer and nonamer sequences flanking less well-conserved 12- or 23-bp spacers. Little quantitative information is known about the contributions of individual RSS positions over the course of the RAG-RSS interaction. We employ a single-molecule method known as tethered particle motion to quantify the formation, stability, and cleavage of the RAG-12RSS-23RSS paired complex (PC) for numerous synthetic and endogenous 12RSSs. We thoroughly investigate the sequence space around a RSS by making 40 different single-bp changes and characterizing the reaction dynamics. We reveal that single-bp changes affect RAG function based on their position: loss of cleavage function (first three positions of the heptamer); reduced propensity for forming the PC (the nonamer and last four bp of the heptamer); or variable effects on PC formation (spacer). We find that the rare usage of some endogenous gene segments can be mapped directly to their adjacent 12RSSs to which RAG binds weakly. The 12RSS, however, cannot explain the high-frequency usage of other gene segments. Finally, we find that RSS nicking, while not required for PC formation, substantially stabilizes the PC. Our findings provide detailed insights into the contribution of individual RSS positions to steps of the RAG-RSS re-action that previously have been difficult to assess quantitatively.nnSummaryV(D)J recombination is a genomic cut-and-paste process for generating diverse antigen-receptor repertoires. The RAG enzyme brings separate gene segments together by binding the neighboring sequences called RSSs, forming a paired complex (PC) before cutting the DNA. There are limited quantitative studies of the sequence-dependent dynamics of the crucial inter-mediate steps of PC formation and cleavage. Here, we quantify individual RAG-DNA dynamics for various RSSs. While RSSs of frequently-used segments do not comparatively enhance PC formation or cleavage, the rare use of some segments can be explained by their neighboring RSSs crippling PC formation and/or cleavage. Furthermore, PC lifetimes reveal DNA-nicking is not required for forming the PC, but PCs with nicks are more stable.
]]></description>
<dc:creator>Hirokawa, S.</dc:creator>
<dc:creator>Chure, G.</dc:creator>
<dc:creator>Belliveau, N. M.</dc:creator>
<dc:creator>Lovely, G. A.</dc:creator>
<dc:creator>Anaya, M.</dc:creator>
<dc:creator>Schatz, D. G.</dc:creator>
<dc:creator>Baltimore, D.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2019-10-04</dc:date>
<dc:identifier>doi:10.1101/791954</dc:identifier>
<dc:title><![CDATA[Sequence-Dependent Dynamics of Synthetic and Endogenous RSSs in V(D)J Recombination]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/792739v1?rss=1">
<title>
<![CDATA[
ASM-Clust: classifying functionally diverse protein families using alignment score matrices 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/792739v1?rss=1</link>
<description><![CDATA[
Rapid advances in sequencing technology have resulted in the availability of genomes from organisms across the tree of life. Accurately interpreting the function of proteins in these genomes is a major challenge, as annotation transfer based on homology frequently results in misannotation and error propagation. This challenge is especially pressing for organisms whose genomes are directly obtained from environmental samples, as interpretation of their physiology and ecology is often based solely on the genome sequence. For complex protein (super)families containing a large number of sequences, classification can be used to determine whether annotation transfer is appropriate, or whether experimental evidence for function is lacking. Here we present a novel computational approach for de novo classification of large protein (super)families, based on clustering an alignment score matrix obtained by aligning all sequences in the family to a small subset of the data. We evaluate our approach on the enolase family in the Structure Function Linkage Database.nnAvailability and implementationASM-Clust is implemented in bash with helper scripts in perl. Scripts comprising ASM-Clust are available for download from https://github.com/dspeth/bioinfo_scripts/tree/master/ASM_clust/
]]></description>
<dc:creator>Speth, D. R.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2019-10-03</dc:date>
<dc:identifier>doi:10.1101/792739</dc:identifier>
<dc:title><![CDATA[ASM-Clust: classifying functionally diverse protein families using alignment score matrices]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/793240v1?rss=1">
<title>
<![CDATA[
Live imaging-assisted domain-specific CRISPR genome editing at single cell resolution in plants 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/793240v1?rss=1</link>
<description><![CDATA[
CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) technology has been widely used for genome engineering in a wide range of organisms1, but much of the development of CRISPR-based genome editing has been aimed toward improving its efficiency and accuracy, so as to obtain genetic materials carrying known and stably heritable genome modifications. Precise spatiotemporal control over genome editing technology at cell type resolution is a key challenge for gene function studies. Some tissue-specific CRISPR genome editing methods relying on phenotypic characterization and fluorescent immune-staining techniques have been developed for biomedical research and gene therapy, they function by spatially controlling expression of Cas9 2. Recent work establishes the presence and location of mutational events at a single cell level in Arabidopsis roots and stomata3,4. Here we present an efficient domain-specific CRISPR-Cas9 system combined with a high resolution live-imaging based screening strategy, applied in the shoot apical meristem of Arabidopsis thaliana. Using the system we investigate PIN-FORMED1 (PIN1) protein functions in tissue morphogenesis and PIN1 mechanical stress response in a cell layer-specific fashion. We find that reported failure to generate new primordia in epidermal PIN1 knockout SAMs is due to a reduction in mechanical stress differences in the sub-epidermal layer. The methods described are applicable to spatial-temporal gene manipulation in plants.
]]></description>
<dc:creator>Li, T.</dc:creator>
<dc:creator>Yan, A.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:date>2019-10-04</dc:date>
<dc:identifier>doi:10.1101/793240</dc:identifier>
<dc:title><![CDATA[Live imaging-assisted domain-specific CRISPR genome editing at single cell resolution in plants]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/800359v1?rss=1">
<title>
<![CDATA[
Listener’s vmPFC simulates speaker choices when reading between the lines 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/800359v1?rss=1</link>
<description><![CDATA[
Humans possess a remarkable ability to understand what is and is not being said by conservational partners. An important class of models hypothesize that listeners decode the intended meaning of an utterance by assuming speakers speak cooperatively, simulating the speakers rational choice process and inverting this process for recovering the speakers most probable meaning. We investigated whether and how rational simulations of speakers are represented in the listeners brain, when subjects participated in a referential communication game inside fMRI. In three experiments, we show that listeners ventromedial prefrontal cortex encodes the probabilistic inference of what a cooperative speaker should say given a communicative goal and context. The listeners striatum responds to the amount of update on the intended meaning, consistent with inverting a simulated mental model. These findings suggest a neural generative mechanism subserved by the frontal-striatal circuits that underlies our ability to understand communicative and, more generally, social actions.
]]></description>
<dc:creator>Mi, Q.</dc:creator>
<dc:creator>Wang, C.</dc:creator>
<dc:creator>Camerer, C. F.</dc:creator>
<dc:creator>Zhu, L.</dc:creator>
<dc:date>2019-10-10</dc:date>
<dc:identifier>doi:10.1101/800359</dc:identifier>
<dc:title><![CDATA[Listener’s vmPFC simulates speaker choices when reading between the lines]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/802538v1?rss=1">
<title>
<![CDATA[
A sex difference in the composition of the rodent postsynaptic density 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/802538v1?rss=1</link>
<description><![CDATA[
SynGAP is a postsynaptic density (PSD) protein that binds to PDZ domains of the scaffold protein PSD-95. We previously reported that heterozygous deletion of synGAP in mice is correlated with increased steady-state levels of other key PSD proteins that bind PSD-95, although the level of PSD-95 remains constant (Walkup et al., 2016). For example, the ratio to PSD-95 of Transmembrane AMPA-Receptor-associated Proteins (TARPs), which mediate binding of AMPA-type glutamate receptors to PSD-95, was increased in young synGAP+/- mice. Here we show that a highly significant increase in TARP in the PSDs of young synGAP+/- rodents is present only in females and not in males. The data reveal a sex difference in the adaptation of the PSD scaffold to synGAP heterozygosity.
]]></description>
<dc:creator>Mastro, T. L.</dc:creator>
<dc:creator>Preza, A.</dc:creator>
<dc:creator>Basu, S.</dc:creator>
<dc:creator>Chattarji, S.</dc:creator>
<dc:creator>Till, S. M.</dc:creator>
<dc:creator>Kind, P. C.</dc:creator>
<dc:creator>Kennedy, M. B.</dc:creator>
<dc:date>2019-10-12</dc:date>
<dc:identifier>doi:10.1101/802538</dc:identifier>
<dc:title><![CDATA[A sex difference in the composition of the rodent postsynaptic density]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/803205v1?rss=1">
<title>
<![CDATA[
Accurate cell tracking and lineage construction in live-cell imaging experiments with deep learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/803205v1?rss=1</link>
<description><![CDATA[
While live-cell imaging is a powerful approach to studying the dynamics of cellular systems, converting these imaging data into quantitative, single-cell records of cellular behavior has been a longstanding challenge. Deep learning methods have proven capable of performing cell segmentation--a critical task for analyzing live-cell imaging data--but their performance in cell tracking has been limited by a lack of dynamic datasets with temporally consistent single-cell labels. We bridge this gap through the integrated development of labeling and deep learning methodology. We present a new framework for scalable, human-in-the-loop labeling of live-cell imaging movies, which we use to label a large collection of movies of fluorescently labeled cell nuclei. We use these data to create a new deep-learning-based cell-tracking method that achieves state-of-the-art performance in cell tracking. We have made all of the data, code, and software publicly available with permissive open-source licensing through the DeepCell projects web portal https://deepcell.org.
]]></description>
<dc:creator>Moen, E.</dc:creator>
<dc:creator>Borba, E.</dc:creator>
<dc:creator>Miller, G.</dc:creator>
<dc:creator>Schwartz, M.</dc:creator>
<dc:creator>Bannon, D.</dc:creator>
<dc:creator>Koe, N.</dc:creator>
<dc:creator>Camplisson, I.</dc:creator>
<dc:creator>Kyme, D.</dc:creator>
<dc:creator>Pavelchek, C.</dc:creator>
<dc:creator>Price, T.</dc:creator>
<dc:creator>Kudo, T.</dc:creator>
<dc:creator>Pao, E.</dc:creator>
<dc:creator>Graf, W.</dc:creator>
<dc:creator>Van Valen, D. A.</dc:creator>
<dc:date>2019-10-13</dc:date>
<dc:identifier>doi:10.1101/803205</dc:identifier>
<dc:title><![CDATA[Accurate cell tracking and lineage construction in live-cell imaging experiments with deep learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/803239v1?rss=1">
<title>
<![CDATA[
Robust Estimation of Bacterial Cell Count from Optical Density 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/803239v1?rss=1</link>
<description><![CDATA[
Optical density (OD) is a fast, cheap, and high-throughput measurement widely used to estimate the density of cells in liquid culture. These measurements, however, cannot be compared between instruments without a standardized calibration protocol and are challenging to relate to actual cell count. We address these shortcomings with an interlaboratory study comparing three OD calibration protocols, as applied to eight strains of E. coli engineered to constitutively express varying levels of GFP. These three protocols--comparison with colloidal silica (LUDOX), serial dilution of silica microspheres, and a reference colony-forming unit (CFU) assay--are all simple, low-cost, and highly accessible. Based on the results produced by the 244 teams completing this interlaboratory study, we recommend calibrating OD using serial dilution of silica microspheres, which readily produces highly precise calibration (95.5% of teams having residuals less than 1.2-fold), is easily assessed for quality control, and as a side effect also assesses the effective linear range of an instrument. Moreover, estimates of cell count from silica microspheres can be combined with fluorescence calibration against fluorescein to obtain units of Molecules of Equivalent Fluorescein (MEFL), allowing direct comparison and data fusion with equivalently calibrated flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
]]></description>
<dc:creator>Beal, J.</dc:creator>
<dc:creator>Farny, N. G.</dc:creator>
<dc:creator>Haddock-Angelli, T.</dc:creator>
<dc:creator>Selvarajah, V.</dc:creator>
<dc:creator>Baldwin, G. S.</dc:creator>
<dc:creator>Buckley-Taylor, R.</dc:creator>
<dc:creator>Gershater, M.</dc:creator>
<dc:creator>Kiga, D.</dc:creator>
<dc:creator>Marken, J. P.</dc:creator>
<dc:creator>Sanchania, V.</dc:creator>
<dc:creator>Sison, A.</dc:creator>
<dc:creator>Workman, C.</dc:creator>
<dc:creator>iGEM Interlab Study Contributors,</dc:creator>
<dc:date>2019-10-13</dc:date>
<dc:identifier>doi:10.1101/803239</dc:identifier>
<dc:title><![CDATA[Robust Estimation of Bacterial Cell Count from Optical Density]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/805317v1?rss=1">
<title>
<![CDATA[
Stimulus-specific neural encoding of a persistent, internal defensive state in the hypothalamus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/805317v1?rss=1</link>
<description><![CDATA[
Persistent neural activity has been described in cortical, hippocampal, and motor networks as mediating short-term working memory of transiently encountered stimuli1-4. Internal emotion states such as fear also exhibit persistence following exposure to an inciting stimulus5,6, but such persistence is typically attributed to circulating stress hormones7-9; whether persistent neural activity also plays a role has not been established. SF1+/Nr5a1+ neurons in the dorsomedial and central subdivision of the ventromedial hypothalamus (VMHdm/c) are necessary for innate and learned defensive responses to predators10-13. Optogenetic activation of VMHdmSF1 neurons elicits defensive behaviors that can outlast stimulation11,14, suggesting it induces a persistent internal state of fear or anxiety. Here we show that VMHdmSF1 neurons exhibit persistent activity lasting tens of seconds, in response to naturalistic threatening stimuli. This persistent activity was correlated with, and required for, persistent thigmotaxic (anxiety-like) behavior in an open-field assay. Microendoscopic imaging of VMHdmSF1 neurons revealed that persistence reflects dynamic temporal changes in population activity, rather than simply synchronous, slow decay of simultaneously activated neurons. Unexpectedly, distinct but overlapping VMHdmSF1 subpopulations were persistently activated by different classes of threatening stimuli. Computational modeling suggested that recurrent neural networks (RNNs) incorporating slow excitation and a modest degree of neurochemical or spatial bias can account for persistent activity that maintains stimulus identity, without invoking genetically determined "labeled lines"15. Our results provide causal evidence that persistent neural activity, in addition to well-established neuroendocrine mechanisms, can contribute to the ability of emotion states to outlast their inciting stimuli, and suggest a mechanism that could prevent over-generalization of defensive responses without the need to evolve hardwired circuits specific for each type of threat.
]]></description>
<dc:creator>Kennedy, A.</dc:creator>
<dc:creator>Kunwar, P. S.</dc:creator>
<dc:creator>Li, L.</dc:creator>
<dc:creator>Wagenaar, D. A.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:date>2019-10-16</dc:date>
<dc:identifier>doi:10.1101/805317</dc:identifier>
<dc:title><![CDATA[Stimulus-specific neural encoding of a persistent, internal defensive state in the hypothalamus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/807800v1?rss=1">
<title>
<![CDATA[
A theory of actions and habits in free-operant behavior: The interaction of rate correlation and contiguity systems. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/807800v1?rss=1</link>
<description><![CDATA[
Contemporary theories of instrumental performance assume that responding can be controlled by two behavioral systems, one goal-directed that encodes the outcome of an action, and one habitual that reinforces the response strength of the same action. Here we present a model of free-operant behavior in which goal-directed control is determined by the correlation between the rates of the action and the outcome whereas the total prediction error generated by contiguous reinforcement by the outcome controls habitual response strength. The outputs of these two systems summate to generate a total response strength. This cooperative model addresses the difference in the behavioral impact of ratio and interval schedules, the transition from goal-directed to habitual control with extended training, the persistence of goal-directed control under choice procedures and following extinction, among other phenomena. In these respects, this dual-system model is unique in its account of free-operant behavior.
]]></description>
<dc:creator>Perez, O. D.</dc:creator>
<dc:creator>Dickinson, A.</dc:creator>
<dc:date>2019-10-17</dc:date>
<dc:identifier>doi:10.1101/807800</dc:identifier>
<dc:title><![CDATA[A theory of actions and habits in free-operant behavior: The interaction of rate correlation and contiguity systems.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/809905v1?rss=1">
<title>
<![CDATA[
Interactions between calmodulin and neurogranin govern the dynamics of CaMKII as a leaky integrator 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/809905v1?rss=1</link>
<description><![CDATA[
Calmodulin-dependent kinase II (CaMKII) has long been known to play an important role in learning and memory as well as long term potentiation (LTP). More recently it has been suggested that it might be involved in the time averaging of synaptic signals, which can then lead to the high precision of information stored at a single synapse. However, the role of the scaffolding molecule, neurogranin (Ng), in governing the dynamics of CaMKII is not yet fully understood. In this work, we adopt a rule-based modeling approach through the Monte Carlo method to study the effect of Ca2+ signals on the dynamics of CaMKII phosphorylation in the postsynaptic density (PSD). Calcium surges are observed in synaptic spines during an EPSP and back-propagating action potential due to the opening of NMDA receptors and voltage dependent calcium channels. We study the differences between the dynamics of phosphorylation of CaMKII monomers and dodecameric holoenzymes. The scaffolding molecule Ng, when present in significant concentration, limits the availability of free calmodulin (CaM), the protein which activates CaMKII in the presence of calcium. We show that it plays an important modulatory role in CaMKII phosphorylation following a surge of high calcium concentration. We find a non-intuitive dependence of this effect on CaM concentration that results from the different affinities of CaM for CaMKII depending on the number of calcium ions bound to the former. It has been shown previously that in the absence of phosphatase CaMKII monomers integrate over Ca2+ signals of certain frequencies through autophosphorylation (Pepke et al, Plos Comp. Bio., 2010). We also study the effect of multiple calcium spikes on CaMKII holoenzyme autophosphorylation, and show that in the presence of phosphatase CaMKII behaves as a leaky integrator of calcium signals, a result that has been recently observed in vivo. Our models predict that the parameters of this leaky integrator are finely tuned through the interactions of Ng, CaM, CaMKII, and PP1. This is a possible mechanism to precisely control the sensitivity of synapses to calcium signals.
]]></description>
<dc:creator>Ordyan, M.</dc:creator>
<dc:creator>Bartol, T. M.</dc:creator>
<dc:creator>Kennedy, M. B.</dc:creator>
<dc:creator>Rangamani, P.</dc:creator>
<dc:creator>Sejnowski, T. J.</dc:creator>
<dc:date>2019-10-18</dc:date>
<dc:identifier>doi:10.1101/809905</dc:identifier>
<dc:title><![CDATA[Interactions between calmodulin and neurogranin govern the dynamics of CaMKII as a leaky integrator]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/817833v1?rss=1">
<title>
<![CDATA[
Caenorhabditis elegans AF4/FMR2 family homolog affl-2 is required for heat shock induced gene expression 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/817833v1?rss=1</link>
<description><![CDATA[
To mitigate the deleterious effects of temperature increases on cellular organization and proteotoxicity, organisms have developed mechanisms to respond to heat stress. In eukaryotes, HSF1 is the master regulator of the heat shock transcriptional response, but the heat shock response pathway is not yet fully understood. From a forward genetic screen for suppressors of heat shock induced gene expression in C. elegans, we identified a new allele of hsf-1 that alters its DNA-binding domain, and three additional alleles of sup-45, a previously uncharacterized genetic locus. We identified sup-45 as one of the two hitherto unknown C. elegans orthologs of the human AF4/FMR2 family proteins, which are involved in regulation of transcriptional elongation rate. We thus renamed sup-45 as affl-2 (AF4/FMR2-Like). affl-2 mutants are egg-laying defective and dumpy, but worms lacking its sole paralog (affl-1) appear wild-type. AFFL-2 is a broadly expressed nuclear protein, and nuclear localization of AFFL-2 is necessary for its role in heat shock response. affl-2 and its paralog are not essential for proper HSF-1 expression and localization after heat shock, which suggests that affl-2 may function downstream or parallel of hsf-1. Our characterization of affl-2 provides insights into the complex processes of transcriptional elongation and regulating heat shock induced gene expression to protect against heat stress.
]]></description>
<dc:creator>Walton, S. J.</dc:creator>
<dc:creator>Wang, H.</dc:creator>
<dc:creator>Quintero-Cadena, P.</dc:creator>
<dc:creator>Bateman, A.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2019-10-25</dc:date>
<dc:identifier>doi:10.1101/817833</dc:identifier>
<dc:title><![CDATA[Caenorhabditis elegans AF4/FMR2 family homolog affl-2 is required for heat shock induced gene expression]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/825299v1?rss=1">
<title>
<![CDATA[
RNA Pol II Length and Disorder Enable Cooperative Scaling of Transcriptional Bursting 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/825299v1?rss=1</link>
<description><![CDATA[
RNA Polymerase II contains a disordered C-terminal domain (CTD) whose length enigmatically correlates with genome size. The CTD is crucial to eukaryotic transcription, yet the functional and evolutionary relevance of this variation remains unclear. Here, we use smFISH, live imaging, and RNA-seq to investigate how CTD length and disorder influence transcription. We find that length modulates the size and frequency of transcriptional bursting. Disorder is highly conserved and mediates CTD-CTD interactions, an ability we show is separable from protein sequence and necessary for efficient transcription. We build a data-driven quantitative model, simulations of which recapitulate experiments and support CTD length promotes initial polymerase recruitment to the promoter but slows down its release from it, and that CTD-CTD interactions enable promoter recruitment of multiple polymerases. Our results reveal how these tunable parameters provide access to a range of transcriptional activity, offering a new perspective for the mechanistic significance of CTD length and disorder in transcription across eukaryotes.
]]></description>
<dc:creator>Quintero-Cadena, P.</dc:creator>
<dc:creator>Lenstra, T. L.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2019-10-31</dc:date>
<dc:identifier>doi:10.1101/825299</dc:identifier>
<dc:title><![CDATA[RNA Pol II Length and Disorder Enable Cooperative Scaling of Transcriptional Bursting]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/825711v1?rss=1">
<title>
<![CDATA[
Functional architecture of motion direction in the mouse superior colliculus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/825711v1?rss=1</link>
<description><![CDATA[
Motion vision is important in guiding animal behavior. Both the retina and the visual cortex process object motion in largely unbiased fashion: all directions are represented at all locations in the visual field. We investigate motion processing in the superior colliculus of the awake mouse, by optically recording neural responses across both hemispheres. Within the retinotopic map, one finds large regions of [~]500 m size where neurons prefer the same direction of motion. This preference is maintained in depth to [~]350 m. The scale of these patches, [~]30 deg of visual angle, is much coarser than the animals visual resolution. A global map of motion direction shows approximate symmetry between the left and right hemispheres and a net bias for upward-nasal motion in the upper visual field. Unlike other parts of the early visual system, the superior colliculus develops a locally biased representation of object motion.
]]></description>
<dc:creator>Li, Y.</dc:creator>
<dc:creator>Turan, Z.</dc:creator>
<dc:creator>Meister, M.</dc:creator>
<dc:date>2019-10-31</dc:date>
<dc:identifier>doi:10.1101/825711</dc:identifier>
<dc:title><![CDATA[Functional architecture of motion direction in the mouse superior colliculus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/825869v1?rss=1">
<title>
<![CDATA[
Stochastic simulation platform for visualization and estimation of transcriptional kinetics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/825869v1?rss=1</link>
<description><![CDATA[
We present an implementation of the Gillespie algorithm that simulates the stochastic kinetics of nascent and mature RNA. Our model includes two-state gene regulation, RNA synthesis initiation and stepwise elongation, release to the cytoplasm, and stepwise degradation, a granular description currently tractable only by simulation. To facilitate comparison with experimental data, the algorithm predicts fluorescent probe signals measurable by single-cell RNA imaging. We approach the inverse problem of estimating underlying parameters in a five-dimensional parameter space and suggest optimization heuristics that successfully recover known reaction rates from simulated gene expression turn-on data. The simulation framework includes a graphical user interface, available as a MATLAB app at https://data.caltech.edu/records/1287.
]]></description>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Wang, M.</dc:creator>
<dc:creator>Golding, I.</dc:creator>
<dc:creator>Xu, H.</dc:creator>
<dc:date>2019-11-02</dc:date>
<dc:identifier>doi:10.1101/825869</dc:identifier>
<dc:title><![CDATA[Stochastic simulation platform for visualization and estimation of transcriptional kinetics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/828228v1?rss=1">
<title>
<![CDATA[
Differential modes of orphan subunit recognition for the WRB/CAML complex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/828228v1?rss=1</link>
<description><![CDATA[
A large proportion of membrane proteins must be assembled into oligomeric complexes for function. How this process occurs is poorly understood, but it is clear that complex assembly must be tightly regulated to avoid accumulation of orphan subunits with potential cytotoxic effects. We interrogated assembly in mammalian cells using a model system of the WRB/CAML complex: an essential insertase for tail-anchored proteins in the endoplasmic reticulum (ER). Our data suggests that the stability of each subunit is differentially regulated. In WRBs absence, CAML folds incorrectly, causing aberrant exposure of a hydrophobic transmembrane domain to the cytosol. When present, WRB can post-translationally correct the topology of CAML both in vitro and in cells. In contrast, WRB can independently fold correctly, but is still degraded in the absence of CAML. We therefore propose at least two distinct regulatory pathways for the surveillance of orphan subunits during complex assembly in the mammalian ER.
]]></description>
<dc:creator>Inglis, A. J.</dc:creator>
<dc:creator>Page, K. R.</dc:creator>
<dc:creator>Guna, A.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:date>2019-11-01</dc:date>
<dc:identifier>doi:10.1101/828228</dc:identifier>
<dc:title><![CDATA[Differential modes of orphan subunit recognition for the WRB/CAML complex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/828723v1?rss=1">
<title>
<![CDATA[
Neuro-computational account of arbitration between imitation and emulation during human observational learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/828723v1?rss=1</link>
<description><![CDATA[
In observational learning (OL), organisms learn from observing the behavior of others. There are at least two distinct strategies for OL. Imitation involves learning to repeat the previous actions of other agents, while in emulation, learning proceeds from inferring the goals and intentions of others. While putative neural correlates for these forms of learning have been identified, a fundamental question remains unaddressed: how does the brain decides which strategy to use in a given situation? Here we developed a novel computational model in which arbitration between the strategies is determined by the predictive reliability, such that control over behavior is adaptively weighted toward the strategy with the most reliable prediction. To test the theory, we designed a novel behavioral task in which our experimental manipulations produced dissociable effects on the reliability of the two strategies. Participants performed this task while undergoing fMRI in two independent studies (the second a pre-registered replication of the first). Behavior manifested patterns consistent with both emulation and imitation and flexibly changed between the two strategies as expected from the theory. Computational modelling revealed that behavior was best described by an arbitration model, in which the reliability of the emulation strategy determined the relative weights allocated to behavior for each strategy. Emulation reliability - the models arbitration signal - was encoded in the ventrolateral prefrontal cortex, temporoparietal junction and rostral cingulate cortex. Being replicated across two fMRI studies, these findings suggest a neuro-computational mechanism for allocating control between emulation and imitation during observational learning.
]]></description>
<dc:creator>Charpentier, C. J.</dc:creator>
<dc:creator>Iigaya, K.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:date>2019-11-04</dc:date>
<dc:identifier>doi:10.1101/828723</dc:identifier>
<dc:title><![CDATA[Neuro-computational account of arbitration between imitation and emulation during human observational learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/833830v1?rss=1">
<title>
<![CDATA[
Genetically encoded phase contrast agents for digital holographic microscopy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/833830v1?rss=1</link>
<description><![CDATA[
Quantitative phase imaging and digital holographic microscopy have shown great promise for visualizing the motion, structure and physiology of microorganisms and mammalian cells in three dimensions. However, these imaging techniques currently lack molecular contrast agents analogous to the fluorescent dyes and proteins that have revolutionized fluorescence microscopy. Here we introduce the first genetically encodable phase contrast agents based on gas vesicles, a unique class of air-filled protein nanostructures derived from buoyant microbes. The relatively low index of refraction of the air-filled core of gas vesicles results in optical phase advancement relative to aqueous media, making them a "positive" phase contrast agent easily distinguished from organelles, dyes, or microminerals. We demonstrate this capability by identifying and tracking the motion of gas vesicles and gas vesicle-expressing bacteria using digital holographic microscopy, and by imaging the uptake of engineered gas vesicles by mammalian cells. These results give phase imaging a biomolecular contrast agent, greatly expanding the capabilities of this powerful technology for three-dimensional biological imaging.
]]></description>
<dc:creator>Farhadi, A.</dc:creator>
<dc:creator>Bedrossian, M.</dc:creator>
<dc:creator>Lee, J.</dc:creator>
<dc:creator>Ho, G. H.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Nadeau, J.</dc:creator>
<dc:date>2019-11-12</dc:date>
<dc:identifier>doi:10.1101/833830</dc:identifier>
<dc:title><![CDATA[Genetically encoded phase contrast agents for digital holographic microscopy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/835322v1?rss=1">
<title>
<![CDATA[
Correlated cryogenic fluorescence microscopy and electron cryotomography shows that exogenous TRIM5α can form hexagonal lattices or autophagy aggregates in vivo 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/835322v1?rss=1</link>
<description><![CDATA[
Members of the TRIM protein family have been shown to gather into structures in both the nucleus and cytoplasm. One TRIM protein family member, TRIM5, has been shown to form cytoplasmic bodies involved in restricting retroviruses such as HIV-1. Here we applied cryogenic correlated light and electron microscopy (cryo-CLEM) to intact mammalian cells expressing YFP-rhTRIM5 and found hexagonal nets were present whose arm-lengths were similar to those of the hexagonal nets formed by purified TRIM5 in-vitro. We also observed YFP-rhTRIM5 within a diversity of structures with characteristics expected for organelles involved in different stages of macroautophagy, including disorganized protein aggregations (sequestosomes), sequestosomes flanked by flat double-membraned vesicles (sequestosome:phagophore complexes), sequestosomes within a double-membraned vesicle (autophagosomes), and sequestosomes within multi-vesicular autophagic vacuoles (autolysosomes or amphisomes). Vaults were also seen in these structures, consistent with their role in autophagy. Our data (i) support recent reports that TRIM5 can form both well-organized signaling complexes and non-signaling aggregates, (ii) offer the first images of the macroautophagy pathway in a near-native state, and (iii) reveal that vaults arrive early in macroautophagy.
]]></description>
<dc:creator>Carter, S. D.</dc:creator>
<dc:creator>Mamede, J. I.</dc:creator>
<dc:creator>Hope, T. J.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2019-11-07</dc:date>
<dc:identifier>doi:10.1101/835322</dc:identifier>
<dc:title><![CDATA[Correlated cryogenic fluorescence microscopy and electron cryotomography shows that exogenous TRIM5α can form hexagonal lattices or autophagy aggregates in vivo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/836676v1?rss=1">
<title>
<![CDATA[
Crosslinking of nucleotide binding domains improves the coupling efficiency of an ABC transporter 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/836676v1?rss=1</link>
<description><![CDATA[
ATP Binding Cassette (ABC) transporters often exhibit significant basal ATPase activity in the absence of transported substrates. To investigate the factors that contribute to this inefficient coupling of ATP hydrolysis to transport, we characterized the structures and functions of variants of the bacterial Atm1 homolog from Novosphingobium aromaticivorans (NaAtm1), including forms with disulfide crosslinks between the nucleotide binding domains. Unexpectedly, disulfide crosslinked variants of NaAtm1 reconstituted into proteoliposomes not only transported oxidized glutathione, but also exhibited more efficient coupling of ATP hydrolysis to GSSG transport than the native transporter. These observations suggest that enhanced conformational dynamics of reconstituted NaAtm1 may contribute to the inefficient use of ATP. Understanding the origins of this uncoupled ATPase activity, and reducing the impact through disulfide crosslinking or other protocols, will be critical for the detailed dissection of ABC transporter mechanism to assure that the ATP dependent steps are indeed relevant to substrate translocation.
]]></description>
<dc:creator>Fan, C.</dc:creator>
<dc:creator>Kaiser, J. T.</dc:creator>
<dc:creator>Rees, D. C.</dc:creator>
<dc:date>2019-11-09</dc:date>
<dc:identifier>doi:10.1101/836676</dc:identifier>
<dc:title><![CDATA[Crosslinking of nucleotide binding domains improves the coupling efficiency of an ABC transporter]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/840066v1?rss=1">
<title>
<![CDATA[
The Degree Distribution of Human Brain Functional Connectivity is Generalized Pareto: A Multi-Scale Analysis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/840066v1?rss=1</link>
<description><![CDATA[
Are degree distributions of human brain functional connectivity networks heavy-tailed? Initial claims based on least-square fitting suggested that brain functional connectivity networks obey power law scaling in their degree distributions. This interpretation has been challenged on methodological grounds. Subsequently, estimators based on maximum-likelihood and non-parametric tests involving surrogate data have been proposed. No clear consensus has emerged as results especially depended on data resolution. To identify the underlying topological distribution of brain functional connectivity calls for a closer examination of the relationship between resolution and statistics of model fitting. In this study, we analyze high-resolution functional magnetic resonance imaging (fMRI) data from the Human Connectome Project to assess its degree distribution across resolutions. We consider resolutions from one thousand to eighty thousand regions of interest (ROIs) and test whether they follow a heavy or short-tailed distribution. We analyze power law, exponential, truncated power law, log-normal, Weibull and generalized Pareto probability distributions. Notably, the Generalized Pareto distribution is of particular interest since it interpolates between heavy-tailed and short-tailed distributions, and it provides a handle on estimating the tails heaviness or shortness directly from the data. Our results show that the statistics support the short-tailed limit of the generalized Pareto distribution, rather than a power law or any other heavy-tailed distribution. Working across resolutions of the data and performing cross-model comparisons, we further establish the overall robustness of the generalized Pareto model in explaining the data. Moreover, we account for earlier ambiguities by showing that down-sampling the data systematically affects statistical results. At lower resolutions models cannot easily be differentiated on statistical grounds while their plausibility consistently increases up to an upper bound. Indeed, more power law distributions are reported at low resolutions (5K) than at higher ones (50K or 80K). However, we show that these positive identifications at low resolutions fail cross-model comparisons and that down-sampling data introduces the risk of detecting spurious heavy-tailed distributions. This dependence of the statistics of degree distributions on sampling resolution has broader implications for neuroinformatic methodology, especially, when several analyses rely on down-sampled data, for instance, due to a choice of anatomical parcellations or measurement technique. Our findings that node degrees of human brain functional networks follow a short-tailed distribution have important implications for claims of brain organization and function. Our findings do not support common simplistic representations of the brain as a generic complex system with optimally efficient architecture and function, modeled with simple growth mechanisms. Instead these findings reflect a more nuanced picture of a biological system that has been shaped by longstanding and pervasive developmental and architectural constraints, including wiring-cost constraints on the centrality architecture of individual nodes.
]]></description>
<dc:creator>Zucca, R.</dc:creator>
<dc:creator>Arsiwalla, X. D.</dc:creator>
<dc:creator>Le, H.</dc:creator>
<dc:creator>Rubinov, M.</dc:creator>
<dc:creator>Gurgui, A.</dc:creator>
<dc:creator>Verschure, P.</dc:creator>
<dc:date>2019-11-13</dc:date>
<dc:identifier>doi:10.1101/840066</dc:identifier>
<dc:title><![CDATA[The Degree Distribution of Human Brain Functional Connectivity is Generalized Pareto: A Multi-Scale Analysis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/847392v1?rss=1">
<title>
<![CDATA[
Caenorhabditis elegans PIEZO Channel Coordinates Multiple Reproductive Tissues to Govern Ovulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/847392v1?rss=1</link>
<description><![CDATA[
The PIEZO proteins are involved in a wide range of developmental and physiological processes. Human PIEZO1 and PIEZO2 are newly identified excitatory mechano-sensitive proteins; they are non-selective ion channels that exhibit a preference for calcium in response to mechanical stimuli. To further understand the function of these proteins, we investigated the roles of pezo-1, the sole PIEZO ortholog in C. elegans. pezo-1 is expressed throughout development in C. elegans, with strong expression in reproductive tissues. A number of deletion alleles as well as a putative gain-of-function mutant caused severe defects in reproduction. A reduced brood size was observed in the strains depleted of PEZO-1. In vivo observations show that oocytes undergo a variety of transit defects as they enter and exit the spermatheca during ovulation. Post ovulation oocytes were frequently damaged during spermathecal contraction. Calcium signaling in the spermatheca is normal during ovulation in pezo-1 mutants, however, pezo-1 interacts genetically with known regulators of calcium signaling. Lastly, loss of PEZO-1 caused defective sperm navigation after being pushed out of the spermatheca during ovulation. Mating with males rescued these reproductive deficiencies in our pezo-1 mutants. These findings suggest that PEZO-1 may act in different reproductive tissues to promote proper ovulation and fertilization in C. elegans.
]]></description>
<dc:creator>Bai, X.</dc:creator>
<dc:creator>Bouffard, J.</dc:creator>
<dc:creator>Lord, A.</dc:creator>
<dc:creator>Brugman, K.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Cram, E. J.</dc:creator>
<dc:creator>Golden, A.</dc:creator>
<dc:date>2019-11-20</dc:date>
<dc:identifier>doi:10.1101/847392</dc:identifier>
<dc:title><![CDATA[Caenorhabditis elegans PIEZO Channel Coordinates Multiple Reproductive Tissues to Govern Ovulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/848168v1?rss=1">
<title>
<![CDATA[
A hydrogel beads based platform for single-cell phenotypic analysis and digital molecular detection 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/848168v1?rss=1</link>
<description><![CDATA[
Microfluidic platforms integrating phenotyping and genotyping approaches have the potential to advance the understanding of single cell genotype-to-phenotype correlations. These correlations can play a key role in tackling antibiotic heteroresistance, cancer cell heterogeneity, and other related fundamental problems. Herein, we report a novel platform that enables both high-throughput digital molecular detection and single-cell phenotypic analysis, utilizing nanoliter-sized biocompatible polyethylene glycol hydrogel beads produced by a convenient and disposable centrifugal droplet generation device. The hydrogel beads have been demonstrated enhanced thermal stability, and achieved uncompromised efficiencies in digital polymerase chain reaction, digital loop-mediated isothermal amplification, and single cell phenotyping. The crosslinked hydrogel network highlights the prospective linkage of various subsequent molecular analyses to address the genotypic differences between cellular subpopulations exhibiting distinct phenotypes. Our platform shows great potential for applications in clinical practice and medical research, and promises new perspectives in mechanism elucidation of environment-evolution interaction and other basic research areas.
]]></description>
<dc:creator>Zhu, Y.</dc:creator>
<dc:creator>Li, J.</dc:creator>
<dc:creator>Lin, X.</dc:creator>
<dc:creator>Huang, X.</dc:creator>
<dc:creator>Hoffmann, M. R.</dc:creator>
<dc:date>2019-11-23</dc:date>
<dc:identifier>doi:10.1101/848168</dc:identifier>
<dc:title><![CDATA[A hydrogel beads based platform for single-cell phenotypic analysis and digital molecular detection]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/852632v1?rss=1">
<title>
<![CDATA[
An improved whole life cycle culture protocol for the hydrozoan genetic model Clytia hemisphaerica. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/852632v1?rss=1</link>
<description><![CDATA[
The jellyfish species Clytia hemisphaerica (Cnidaria, Hydrozoa) has emerged as a new experimental model animal in the last decade. Favorable characters include a fully transparent body suitable for microscopy, daily gamete production and a relatively short life cycle. Furthermore, whole genome sequence assembly and efficient gene editing techniques using CRISPR/Cas9 have opened new possibilities for genetic studies. The quasi-immortal vegetatively-growing polyp colony stage provides a practical means to maintain mutant strains. In the context of developing Clytia as a genetic model, we report here an improved whole life cycle culture method including an aquarium tank system designed for culture of the tiny jellyfish form. We have compared different feeding regimes using Artemia larvae as the food and demonstrate that the stage-dependent feeding control is the key for rapid and reliable medusa and polyp rearing. Metamorphosis of the planula larvae into a polyp colony can be efficiently induced using a new synthetic peptide. The optimized procedures detailed here make it practical to generate new genetically modified Clytia strains and to safely maintain their whole life cycle in the laboratory.
]]></description>
<dc:creator>Lechable, M.</dc:creator>
<dc:creator>Jan, A.</dc:creator>
<dc:creator>Weissbourd, B. C.</dc:creator>
<dc:creator>Uveira, J.</dc:creator>
<dc:creator>Gissat, L.</dc:creator>
<dc:creator>Collet, S.</dc:creator>
<dc:creator>Gilletta, L.</dc:creator>
<dc:creator>Chevalier, S.</dc:creator>
<dc:creator>Leclere, L.</dc:creator>
<dc:creator>Peron, S.</dc:creator>
<dc:creator>Barreau, C.</dc:creator>
<dc:creator>Lasbleiz, R.</dc:creator>
<dc:creator>Houliston, E.</dc:creator>
<dc:creator>Momose, T.</dc:creator>
<dc:date>2019-11-25</dc:date>
<dc:identifier>doi:10.1101/852632</dc:identifier>
<dc:title><![CDATA[An improved whole life cycle culture protocol for the hydrozoan genetic model Clytia hemisphaerica.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/853028v1?rss=1">
<title>
<![CDATA[
Odd-paired is a late-acting pioneer factor coordinating with Zelda to broadly regulate gene expression in early embryos 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/853028v1?rss=1</link>
<description><![CDATA[
Pioneer factors such as Zelda help initiate zygotic transcription in Drosophila early embryos, but whether other factors support this dynamic process is unclear. Odd-paired (Opa), a zinc-finger transcription factor expressed at cellularization, controls transition of genes from pair-rule to segmental patterns along the anterior-posterior axis. Finding that Opa also regulates late expression through enhancer sog_Distal, along the dorso-ventral axis, we hypothesized that Opa acts as a general timing factor. Chromatin-immunoprecipitation (ChIP-seq) confirmed Opa in vivo binding to sog_Distal but also identified widespread binding throughout the genome, comparable to Zelda. Furthermore, chromatin assays (ATAC-seq) demonstrate that Opa, like Zelda, influences chromatin accessibility genome-wide, suggesting both are pioneer factors with common as well as distinct targets. Lastly, embryos lacking opa exhibit widespread, late patterning defects spanning both axes. Collectively, these data suggest Opa, a general timing factor and likely a late-acting pioneer factor, heralds in a secondary wave of zygotic gene expression.
]]></description>
<dc:creator>Koromila, T.</dc:creator>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>Iwasaki, Y.</dc:creator>
<dc:creator>He, P.</dc:creator>
<dc:creator>Pachter, L. S.</dc:creator>
<dc:creator>Gergen, J. P.</dc:creator>
<dc:creator>Stathopoulos, A.</dc:creator>
<dc:date>2019-11-23</dc:date>
<dc:identifier>doi:10.1101/853028</dc:identifier>
<dc:title><![CDATA[Odd-paired is a late-acting pioneer factor coordinating with Zelda to broadly regulate gene expression in early embryos]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/853044v1?rss=1">
<title>
<![CDATA[
Viscoelastic properties of ECM-rich embryonic microenvironments 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/853044v1?rss=1</link>
<description><![CDATA[
The material properties of tissues and their mechanical state is an important factor during development, disease, regenerative medicine and tissue engineering. Here we describe a microrheological measurement technique utilizing aggregates of microinjected ferromagnetic nickel particles to probe the viscoelastic properties of embryonic tissues. Quail embryos were cultured in a plastic incubator chamber located at the center of two pairs of crossed electromagnets. We estimate the Youngs modulus of the ECM-rich region separating the mesoderm and endoderm in Hamburger Hamilton stage 6-10 quail embryos as 300{+/-}100 Pa. We found a pronounced viscoelastic behavior consistent with a Zener (standard generalized solid) model. The viscoelastic response is about 45% of the total response, with a characteristic relaxation time of 1.3 sec.
]]></description>
<dc:creator>Akos, Z.</dc:creator>
<dc:creator>Isai, D. G.</dc:creator>
<dc:creator>Rajasingh, S.</dc:creator>
<dc:creator>Kosa, E.</dc:creator>
<dc:creator>Ghazvini, S.</dc:creator>
<dc:creator>Dhar, P.</dc:creator>
<dc:creator>Czirok, A.</dc:creator>
<dc:date>2019-11-23</dc:date>
<dc:identifier>doi:10.1101/853044</dc:identifier>
<dc:title><![CDATA[Viscoelastic properties of ECM-rich embryonic microenvironments]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/858266v1?rss=1">
<title>
<![CDATA[
Construction of an inducible amyloid expression circuit in Bacillus megaterium: A case study with CsgA and TasA 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/858266v1?rss=1</link>
<description><![CDATA[
Environmental applications of synthetic biology such as water remediation require engineered strains to function robustly in a fluctuating and potentially hostile environment. The construction of synthetic biofilm formation circuits could potentially alleviate this issue by promoting cell survival. Towards this end, we construct a xylose-inducible system for the expression of the functional amyloids CsgA and TasA in the soil bacterium Bacillus megaterium. We find that although both amyloids are expressed, only TasA is successfully exported from the cells. Furthermore, expression of CsgA results in a significant growth penalty for the cells while expression of TasA does not. Finally, we show that TasA expression conveys a small but detectable increase in cells adhesion to nickel beads. These results suggest that TasA is a promising candidate for future work on synthetic biofilm formation in B. megaterium.
]]></description>
<dc:creator>Larsson, E. M.</dc:creator>
<dc:creator>McManus, J. B.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2019-11-29</dc:date>
<dc:identifier>doi:10.1101/858266</dc:identifier>
<dc:title><![CDATA[Construction of an inducible amyloid expression circuit in Bacillus megaterium: A case study with CsgA and TasA]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/858993v1?rss=1">
<title>
<![CDATA[
Theoretical investigation of a genetic switch for metabolic adaptation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/858993v1?rss=1</link>
<description><![CDATA[
Membrane transporters carry key metabolites through the cell membrane and, from a resource standpoint, are hypothesized to be produced when necessary. The expression of membrane transporters in metabolic pathways is often upregulated by the transporter substrate. In E. coli, such systems include for example the lacY, araFGH, and xylFGH genes, which encode for lactose, arabinose, and xylose transporters, respectively. As a case study of a minimal system, we build a generalizable physical model of the xapABR genetic circuit, which features a regulatory feedback loop through membrane transport (positive feedback) and enzymatic degradation (negative feedback) of an inducer. Dynamical systems analysis and stochastic simulations show that the membrane transport makes the model system bistable in certain parameter regimes. Thus, it serves as a genetic "on-off" switch, enabling the cell to only produce a set of metabolic enzymes when the corresponding metabolite is present in large amounts. We find that the negative feedback from the degradation enzyme does not significantly disturb the positive feedback from the membrane transporter. We investigate hysteresis in the switching and discuss the role of cooperativity and multiple binding sites in the model circuit. Fundamentally, this work explores how a stable genetic switch for a set of enzymes is obtained from transcriptional auto-activation of a membrane transporter through its substrate.
]]></description>
<dc:creator>Laxhuber, K. S.</dc:creator>
<dc:creator>Morrison, M.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2019-11-28</dc:date>
<dc:identifier>doi:10.1101/858993</dc:identifier>
<dc:title><![CDATA[Theoretical investigation of a genetic switch for metabolic adaptation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/000075v1?rss=1">
<title>
<![CDATA[
A Scalable Formulation for Engineering Combination Therapies for Evolutionary Dynamics of Disease 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/000075v1?rss=1</link>
<description><![CDATA[
It has been shown that optimal controller synthesis for positive systems can be formulated as a linear program. Leveraging these results, we propose a scalable iterative algorithm for the systematic design of sparse, small gain feedback strategies that stabilize the evolutionary dynamics of a generic disease model. We achieve the desired feedback structure by augmenting the optimization problems with {ell}1 and {ell}2 regularization terms, and illustrate our method on an example inspired by an experimental study aimed at finding appropriate HIV neutralizing antibody therapy combinations in the presence of escape mutants.
]]></description>
<dc:creator>Vanessa Jonsson</dc:creator>
<dc:creator>Anders Rantzer</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2013-11-07</dc:date>
<dc:identifier>doi:10.1101/000075</dc:identifier>
<dc:title><![CDATA[A Scalable Formulation for Engineering Combination Therapies for Evolutionary Dynamics of Disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2013-11-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/000430v1?rss=1">
<title>
<![CDATA[
Negative autoregulation matches production and demand in synthetic transcriptional networks 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/000430v1?rss=1</link>
<description><![CDATA[
We propose a negative feedback architecture that regulates activity of artificial genes, or "genelets", to meet their output downstream demand, achieving robustness with respect to uncertain open-loop output production rates. In particular, we consider the case where the outputs of two genelets interact to form a single assembled product. We show with analysis and experiments that negative autoregulation matches the production and demand of the outputs: the magnitude of the regulatory signal is proportional to the "error" between the circuit output concentration and its actual demand. This two-device system is experimentally implemented using in vitro transcriptional networks, where reactions are systematically designed by optimizing nucleic acid sequences with publicly available software packages. We build a predictive ordinary differential equation (ODE) model that captures the dynamics of the system, and can be used to numerically assess the scalability of this architecture to larger sets of interconnected genes. Finally, with numerical simulations we contrast our negative autoregulation scheme with a cross-activation architecture, which is less scalable and results in slower response times.
]]></description>
<dc:creator>Elisa Franco</dc:creator>
<dc:creator>Giulia Giordano</dc:creator>
<dc:creator>Per-Ola Forsberg</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2013-11-14</dc:date>
<dc:identifier>doi:10.1101/000430</dc:identifier>
<dc:title><![CDATA[Negative autoregulation matches production and demand in synthetic transcriptional networks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2013-11-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/007385v1?rss=1">
<title>
<![CDATA[
Negative Feedback Facilitates Temperature Robustness in Biomolecular Circuit Dynamics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/007385v1?rss=1</link>
<description><![CDATA[
Temporal dynamics in many biomolecular circuits can change with temperature because of the temperature dependence of underlying reaction rate parameters. It is generally unclear what circuit mechanisms can inherently facilitate robustness in the dynamics to variations in temperature. Here, we address this issue using a combination of mathematical models and experimental measurements in a cell-free transcription-translation system. We find that negative transcriptional feedback can reduce the effect of temperature variation on circuit dynamics. Further, we find that effective negative feedback due to first-order degradation mechanisms can also enable such a temperature robustness effect. Finally, we estimate temperature dependence of key parameters mediating such negative feedback mechanisms. These results should be useful in the design of temperature robust circuit dynamics.
]]></description>
<dc:creator>Shaunak Sen</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2014-07-22</dc:date>
<dc:identifier>doi:10.1101/007385</dc:identifier>
<dc:title><![CDATA[Negative Feedback Facilitates Temperature Robustness in Biomolecular Circuit Dynamics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2014-07-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/009480v1?rss=1">
<title>
<![CDATA[
Synthesizing Combination Therapies for Evolutionary Dynamics of Disease for Nonlinear Pharmacodynamics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/009480v1?rss=1</link>
<description><![CDATA[
Our previous results proposed an iterative scalable algorithm for the systematic design of sparse, small gain feedback strategies that stabilize the evolutionary dynamics of a generic disease model with linear pharmacodynamics. In this manuscript, we use piecewise linear approximations to model nonlinear drug effects. We leverage results from optimal controller synthesis for positive systems to formulate the feedback synthesis problem as an optimization problem that sequentially explores piecewise linear subsystems corresponding to higher and higher treatment dosages.
]]></description>
<dc:creator>Vanessa Jonsson</dc:creator>
<dc:creator>Nikolai Matni</dc:creator>
<dc:creator>Richard M. Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2014-09-21</dc:date>
<dc:identifier>doi:10.1101/009480</dc:identifier>
<dc:title><![CDATA[Synthesizing Combination Therapies for Evolutionary Dynamics of Disease for Nonlinear Pharmacodynamics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2014-09-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/017269v1?rss=1">
<title>
<![CDATA[
Design of a Toolbox of RNA Thermometers 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/017269v1?rss=1</link>
<description><![CDATA[
Biomolecular temperature sensors can be used for efficient control of large-volume bioreactors, for spatiotemporal control and imaging of gene expression, as well as to engineer robustness to temperature in biomolecular circuit design. While RNA-based sensors, called  thermometers, have been investigated in natural and synthetic contexts, an important challenge is to design different responses to temperature, differing in sensitivities and thresholds. We address this issue using experimental measurements in cells and in cell-free biomolecular  breadboards in combination with computations of RNA thermodynamics. We designed a library of RNA thermometers, finding, computationally, that it could contain a multiplicity of responses to temperature. We constructed this library and found a wide range of responses to temperature, ranging from 3.5-fold to over 10-fold in the temperature range 29{degrees}C - 37{degrees}C. These were largely linear responses with over 10-fold difference in slopes. We correlated the measured responses with computational expectations, finding that while there was no strong correlation in the individual values, the overall trends were similar. These results present a toolbox of RNA-based circuit elements with varying temperature sensitivities.
]]></description>
<dc:creator>Shaunak Sen</dc:creator>
<dc:creator>Divyansh Apurva</dc:creator>
<dc:creator>Rohit Satija</dc:creator>
<dc:creator>Dan Siegal</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-03-30</dc:date>
<dc:identifier>doi:10.1101/017269</dc:identifier>
<dc:title><![CDATA[Design of a Toolbox of RNA Thermometers]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-03-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/018317v1?rss=1">
<title>
<![CDATA[
A cell-free framework for biological systems engineering 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/018317v1?rss=1</link>
<description><![CDATA[
SUMMARYWhile complex dynamic biological networks control gene expression and metabolism in all living organisms, engineering comparable synthetic networks remains challenging1,2. Conducting extensive, quantitative and rapid characterization during the design and implementation process of synthetic networks is currently severely limited due to cumbersome molecular cloning and the difficulties associated with measuring parts, components and systems in cellular hosts. Engineering gene networks in a cell-free environment promises to be an efficient and effective approach to rapidly develop novel biological systems and understand their operating regimes3-5. However, it remains questionable whether complex synthetic networks behave similarly in cells and a cell-free environment, which is critical for in vitro approaches to be of significance to biological engineering. Here we show that synthetic dynamic networks can be readily implemented, characterized, and engineered in a cell-free framework and consequently transferred to cellular hosts. We implemented and characterized the "repressilator"6, a three-node negative feedback oscillator in vitro. We then used our cell-free framework to engineer novel three-node, four-node, and five-node negative feedback architectures going from the characterization of circuit components to the rapid analysis of complete networks. We validated our cell-free approach by transferring these novel three-node and five-node oscillators to Escherichia coli, resulting in robust and synchronized oscillations reflecting the in vitro observation. We demonstrate that comprehensive circuit engineering can be performed in a cell-free system and that the in vitro results have direct applicability in vivo. Cell-free synthetic biology thus has the potential to drastically speed up design-build-test cycles in biological engineering and enable the quantitative characterization of synthetic and natural networks.
]]></description>
<dc:creator>Henrike Niederholtmeyer</dc:creator>
<dc:creator>Zachary Sun</dc:creator>
<dc:creator>Yutaka Hori</dc:creator>
<dc:creator>Enoch Yeung</dc:creator>
<dc:creator>Amanda Verpoorte</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator>Sebastian J Maerkl</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-04-21</dc:date>
<dc:identifier>doi:10.1101/018317</dc:identifier>
<dc:title><![CDATA[A cell-free framework for biological systems engineering]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-04-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/019687v1?rss=1">
<title>
<![CDATA[
The effects of time-varying temperature on delays in genetic networks 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/019687v1?rss=1</link>
<description><![CDATA[
Delays in gene networks result from the sequential nature of protein assembly. However, it is unclear how models of gene networks that use delays should be modified when considering time-dependent changes in temperature. This is important, as delay is often used in models of genetic oscillators that can be entrained by periodic fluctuations in temperature. Here, we analytically derive the time dependence of delay distributions in response to time-varying temperature changes. We find that the resulting time-varying delay is nonlinearly dependent on parameters of the time-varying temperature such as amplitude and frequency, therefore, applying an Arrhenius scaling may result in erroneous conclusions. We use these results to examine a model of a synthetic gene oscillator with temperature compensation. We show that temperature entrainment follows from the same mechanism that results in temperature compensation. Under a common Arrhenius scaling alone, the frequency of the oscillator is sensitive to changes in the mean temperature but robust to changes in the frequency of a periodically time-varying temperature. When a mechanism for temperature compensation is included in the model, however, we show that the oscillator is entrained by periodically varying temperature even when maintaining insensitivity to the mean temperature.
]]></description>
<dc:creator>Marcella M Gomez</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator>Matthew R Bennett</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-05-22</dc:date>
<dc:identifier>doi:10.1101/019687</dc:identifier>
<dc:title><![CDATA[The effects of time-varying temperature on delays in genetic networks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-05-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/031385v1?rss=1">
<title>
<![CDATA[
Evolutionary analysis across mammals reveals distinct classes of long noncoding RNAs 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/031385v1?rss=1</link>
<description><![CDATA[
BACKGROUNDRecent advances in transcriptome sequencing have enabled the discovery of thousands of long non-coding RNAs (lncRNAs) across multitudes of species. Though several lncRNAs have been shown to play important roles in diverse biological processes, the functions and mechanisms of most lncRNAs remain unknown. Two significant obstacles lie between transcriptome sequencing and functional characterization of lncRNAs: 1) identifying truly noncoding genes from de novo reconstructed transcriptomes, and 2) prioritizing hundreds of resulting putative lncRNAs from each sample for downstream experimental interrogation.nnRESULTSWe present slnckv, a computational lncRNA discovery tool that produces a high-quality set of lncRNAs from RNA-Sequencing data and further prioritizes lncRNAs by characterizing selective constraint as a proxy for function. Our filtering pipeline is comparable to manual curation efforts and more sensitive than previously published approaches. Further, we develop, for the first time, a sensitive alignment pipeline for aligning lncRNA loci and propose new evolutionary metrics relevant for both sequence and transcript evolution. Our analysis reveals that selection acts in several distinct patterns, and uncovers two notable classes of lncRNAs: one showing strong purifying selection at RNA sequence and another where constraint is restricted to the regulation but not the sequence of the transcript.nnCONCLUSIONOur novel comparative methods for lncRNAs reveals 233 constrained lncRNAs out of tens of thousands of currently annotated transcripts, which we believe should be prioritized for further interrogation. To aid in their analysis we provide the slncky Evolution Browser as a resource for experimentalists.
]]></description>
<dc:creator>Jenny Chen</dc:creator>
<dc:creator>Alexander A. Shishkin</dc:creator>
<dc:creator>Xiaopeng Zhu</dc:creator>
<dc:creator>Sabah Kadri</dc:creator>
<dc:creator>Itay Maza</dc:creator>
<dc:creator>Jacob H Hanna</dc:creator>
<dc:creator>Aviv Regev</dc:creator>
<dc:creator>Manuel Garber</dc:creator>
<dc:creator></dc:creator>
<dc:date>2015-11-11</dc:date>
<dc:identifier>doi:10.1101/031385</dc:identifier>
<dc:title><![CDATA[Evolutionary analysis across mammals reveals distinct classes of long noncoding RNAs]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2015-11-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/046367v1?rss=1">
<title>
<![CDATA[
Structural and kinetic analysis of the COP9-Signalosome activation and the cullin-RING ubiquitin ligase deneddylation cycle 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/046367v1?rss=1</link>
<description><![CDATA[
The COP9-Signalosome (CSN) regulates cullin-RING ubiquitin ligase (CRL) activity and assembly by cleaving Nedd8 from cullins. Free CSN is autoinhibited, and it remains unclear how it becomes activated. We combine structural and kinetic analyses to identify mechanisms that contribute to CSN activation and Nedd8 deconjugation. Both CSN and neddylated substrate undergo large conformational changes upon binding, with important roles played by the N-terminal domains of Csn2 and Csn4 and the RING domain of Rbx1 in enabling formation of a high affinity, fully active complex. The RING domain is crucial for deneddylation, and works in part through conformational changes involving insert-2 of Csn6. Nedd8 deconjugation and re-engagement of the active site zinc by the autoinhibitory Csn5 glutamate-104 diminish affinity for Cul1/Rbx1 by ~100-fold, resulting in its rapid ejection from the active site. Together, these mechanisms enable a dynamic deneddylation-disassembly cycle that promotes rapid remodeling of the cellular CRL network.
]]></description>
<dc:creator>Ruzbeh Mosadeghi</dc:creator>
<dc:creator>Kurt M Reichermeier</dc:creator>
<dc:creator>Martin Winkler</dc:creator>
<dc:creator>Anne Schreiber</dc:creator>
<dc:creator>Justin M Reitsma</dc:creator>
<dc:creator>Yaru Zhang</dc:creator>
<dc:creator>Florian Stengel</dc:creator>
<dc:creator>Junyue Cao</dc:creator>
<dc:creator>Minsoo Kim</dc:creator>
<dc:creator>Michael J Sweredoski</dc:creator>
<dc:creator>Sonja Hess</dc:creator>
<dc:creator>Alexander Leitner</dc:creator>
<dc:creator>Ruedi Aebersold</dc:creator>
<dc:creator>Matthias Peter</dc:creator>
<dc:creator>Raymond J Deshaies</dc:creator>
<dc:creator>Radolsav I Enchev</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-03-30</dc:date>
<dc:identifier>doi:10.1101/046367</dc:identifier>
<dc:title><![CDATA[Structural and kinetic analysis of the COP9-Signalosome activation and the cullin-RING ubiquitin ligase deneddylation cycle]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-03-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/048710v1?rss=1">
<title>
<![CDATA[
Development of prokaryotic cell-free systems for synthetic biology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/048710v1?rss=1</link>
<description><![CDATA[
Prokaryotic cell-free systems are currently heavily used for the production of protein that can be otherwise challenging to produce in cells. However, historically cell-free systems were used to explore natural phenomena before the advent of genetic modification and transformation technology. Recently, synthetic biology has seen a resurgence of this historical use of cell-free systems as a prototyping tool of synthetic and natural genetic circuits. For these cell-free systems to be effective prototyping tools, an understanding of cell-free system mechanics must be established that is not purely protein-expression driven. Here we discuss the development of E. coli-based cell-free systems, with an emphasis on documenting published extract and energy preparation methods into a uniform format. We also discuss additional considerations when applying cell-free systems to synthetic biology.
]]></description>
<dc:creator>Abel C Chiao</dc:creator>
<dc:creator>Richard M Murray</dc:creator>
<dc:creator>Zachary Z Sun</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-04-15</dc:date>
<dc:identifier>doi:10.1101/048710</dc:identifier>
<dc:title><![CDATA[Development of prokaryotic cell-free systems for synthetic biology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-04-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/072439v1?rss=1">
<title>
<![CDATA[
Zika infection of neural progenitor cells perturbs transcription in neurodevelopmental pathways 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/072439v1?rss=1</link>
<description><![CDATA[
BackgroundA recent study of the gene expression patterns of Zika virus (ZIKV) infected human neural progenitor cells (hNPCs) revealed transcriptional dysregulation and identified cell-cycle-related pathways that are affected by infection. However deeper exploration of the information present in the RNA-Seq data can be used to further elucidate the manner in which Zika infection of hNPCs affects the transcriptome, refining pathway predictions and revealing isoform-specific dynamics.nnMethodology/Principal FindingsWe analyzed data published by Tang et al. using state-of-the-art tools for transcriptome analysis. By accounting for the experimental design and estimation of technical and inferential variance we were able to pinpoint Zika infection affected pathways that highlight Zikas neural tropism. The examination of differential genes reveals cases of isoform divergence.nnConclusions/SignificanceTranscriptome analysis of Zika infected hNPCs has the potential to identify the molecular signatures of Zika infected neural cells. These signatures may be useful for diagnostics and for the resolution of infection pathways that can be used to harvest specific targets for further study.
]]></description>
<dc:creator>Lynn Yi</dc:creator>
<dc:creator>Harold Pimentel</dc:creator>
<dc:creator>Lior Pachter</dc:creator>
<dc:creator></dc:creator>
<dc:date>2016-08-30</dc:date>
<dc:identifier>doi:10.1101/072439</dc:identifier>
<dc:title><![CDATA[Zika infection of neural progenitor cells perturbs transcription in neurodevelopmental pathways]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-08-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/083113v1?rss=1">
<title>
<![CDATA[
Transcriptomic Description of an Endogenous Female State in C. elegans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/083113v1?rss=1</link>
<description><![CDATA[
Understanding genome and gene function in a whole organism requires us to fully understand the life cycle and the physiology of the organism in question. Although it is traditionally though of as a hermaphrodite, C. elegans XX animals become (endogenous) females after 3 days of egg-laying. The molecular physiology of this state has not been studied as intensely as other parts of the life cycle, in spite of documented changes in behavior and metabolism that occur at this stage. To study the female state of C. elegans, we designed an experiment to measure the transcriptome of 1st day adult females, endogenous, 6th day adult females, as well as mutant feminized worms that never go through a hermaphrodite stage at these time points. Using this experimental design, we were able to measure the effects of biological aging from the transition into the female state. We find that spermless young adult animals partially phenocopy 6 day old wild-type animals that have depleted their sperm after egg-laying, and that spermless animals also exhibit fewer transcriptomic changes associated with aging throughout these 6 days. Our results indicate that sperm loss is responsible for some of the naturally occuring transcriptomic changes that occur during the life cycle of these animals. These changes involve a variety of factors, and they are enriched in transcription factors canonically associated with neuronal development and differentiation. Our data provide a high-quality picture of the changes that happen in global gene expression throughout the period of early aging in the worm.
]]></description>
<dc:creator>Angeles-Albores, D.</dc:creator>
<dc:creator>Leighton, D. H. W.</dc:creator>
<dc:creator>Tsou, T.</dc:creator>
<dc:creator>Khaw, T. H.</dc:creator>
<dc:creator>Antoshechkin, I.</dc:creator>
<dc:creator>Sternberg, P.</dc:creator>
<dc:date>2016-10-27</dc:date>
<dc:identifier>doi:10.1101/083113</dc:identifier>
<dc:title><![CDATA[Transcriptomic Description of an Endogenous Female State in C. elegans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-10-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/092619v1?rss=1">
<title>
<![CDATA[
Resolving the Functional Significance of BRCA1 RING Domain Missense Substitutions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/092619v1?rss=1</link>
<description><![CDATA[
Part 1Development and calibration of suitably accurate functional assays for BRCA1 RING domain and BRCT domain missense substitutions could dramatically accelerate clinical classification of rare missense substitutions observed in that gene. Leveraging data from 68,000 full sequence tests of BRCA1 and BRCA2, plus data from the limited number of already classified BRCA1 RING domain missense substitutions, we used logistic regression and related techniques to evaluate three BRCA1 RING domain assays. These were recently described high throughput yeast 2-hybrid and E3 ubiquitin ligase assays, plus a newly developed mammalian 2-hybrid assay. While there were concerns about the accuracy of the yeast 2-hybrid assay and the indirect nature of the ubiquitin ligase assay, the mammalian 2-hybrid assay had excellent correlation with existing missense substitution classifications. After calibration, this assay contributed to classification of one newly reported BRCA1 missense substitution. In principal, the mammalian 2-hybrid assay could be converted to a high-throughput format that would likely retain suitable accuracy.

Part 2How does one achieve clinically applicable classification of the vast majority of all possible sequence variants in disease susceptibility genes? BRCA1 is a high-risk susceptibility gene for breast and ovarian cancer. Pathogenic protein truncating variants are scattered across the open reading frame, but all known missense substitutions that are pathogenic because of missense dysfunction are located in either the amino-terminal RING domain or the carboxy-terminal BRCT domain. Heterodimerization of the BRCA1 and BARD1 RING domains is a molecularly defined obligate activity. Hence, we tested every BRCA1 RING domain missense substitution that can be created by a single nucleotide change for heterodimerization with BARD1 in a Mammalian 2-hybrid (M2H) assay. Downstream of the M2H laboratory assay, we addressed three additional challenges: assay calibration, validation thereof, and integration of the calibrated results with other available data such as computational evidence and patient/population observational data to achieve clinically applicable classification. Overall, we found that about 20% of BRCA1 RING domain missense substitutions are pathogenic. Using a Bayesian point system for data integration and variant classification, we achieved clinical classification of about 89% of observed missense substitutions. Moreover, among missense substitutions not present in the human observational data used here, we find an additional 47 with concordant computational and functional assay evidence in favor of pathogenicity; these are particularly likely to be classified as Likely Pathogenic once human observational data become available.
]]></description>
<dc:creator>Paquette, A.</dc:creator>
<dc:creator>Tao, K.</dc:creator>
<dc:creator>Stark, A. W.</dc:creator>
<dc:creator>Rosenthal, J.</dc:creator>
<dc:creator>Bell, R.</dc:creator>
<dc:creator>Thompson, B. A.</dc:creator>
<dc:creator>Milash, B. A.</dc:creator>
<dc:creator>Gertz, J.</dc:creator>
<dc:creator>Varley, K. E.</dc:creator>
<dc:creator>Thomas, A.</dc:creator>
<dc:creator>Boucher, K.</dc:creator>
<dc:creator>Foulkes, W. D.</dc:creator>
<dc:creator>Goldgar, D. E.</dc:creator>
<dc:creator>Tavtigian, S. V.</dc:creator>
<dc:date>2016-12-08</dc:date>
<dc:identifier>doi:10.1101/092619</dc:identifier>
<dc:title><![CDATA[Resolving the Functional Significance of BRCA1 RING Domain Missense Substitutions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-12-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/106369v1?rss=1">
<title>
<![CDATA[
Phenotype and gene ontology enrichment as guides for disease modeling in C. elegans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/106369v1?rss=1</link>
<description><![CDATA[
Genome-wide experiments have the capacity to generate massive amounts of unbiased data about an organism. In order to interpret this data, dimensionality reduction techniques are required. One approach is to annotate genes using controlled languages and to test experimental datasets for term enrichment using probabilistic methods. Although gene, phenotype and anatomy ontologies exist for C. elegans, no unified software offers enrichment analyses of all the ontologies using the same methodology. Here, we present the WormBase Enrichment Suite, which offers users the ability to test all nematode ontologies simultaneously. We show that the WormBase Enrichment Suite provides valuable insight into different biological problems. Briefly, we show that phenotype enrichment analysis (PEA) can help researchers identify disease phenologs, phenotypes that are homologous across species, which can inform disease modeling in C. elegans. The WormBase Enrichment Suite analysis can also shed light on RNA-seq datasets by showing what molecular functions are enriched, which phenotypes these functions are implicated in and what tissues are overrepresented in the dataset. Finally, we explore the phenotype-anatomy relationship, showing that a small subset of highly specific tissues are disproportionately likely to cause an Egl phenotype, but inferring tissue expression from an Egl phenotype is limited to the largest tissues.
]]></description>
<dc:creator>Angeles-Albores, D.</dc:creator>
<dc:creator>Lee, R. Y.</dc:creator>
<dc:creator>Chan, J.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2017-02-07</dc:date>
<dc:identifier>doi:10.1101/106369</dc:identifier>
<dc:title><![CDATA[Phenotype and gene ontology enrichment as guides for disease modeling in C. elegans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-02-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/111013v1?rss=1">
<title>
<![CDATA[
An allosteric theory of transcription factor induction 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/111013v1?rss=1</link>
<description><![CDATA[
Allosteric regulation is found across all domains of life, yet we still lack simple, predictive theories that directly link the experimentally tunable parameters of a system to its input-output response. To that end, we present a general theory of allosteric transcriptional regulation using the Monod-Wyman-Changeux model. We rigorously test this model using the ubiquitous simple repression motif in bacteria by first predicting the behavior of strains that span a large range of repressor copy numbers and DNA binding strengths and then constructing and measuring their response. Our model not only accurately captures the induction profiles of these strains but also enables us to derive analytic expressions for key properties such as the dynamic range and [EC50]. Finally, we derive an expression for the free energy of allosteric repressors which enables us to collapse our experimental data onto a single master curve that captures the diverse phenomenology of the induction profiles.
]]></description>
<dc:creator>Razo-Mejia, M.</dc:creator>
<dc:creator>Barnes, S. L.</dc:creator>
<dc:creator>Belliveau, N. M.</dc:creator>
<dc:creator>Chure, G.</dc:creator>
<dc:creator>Einav, T.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2017-02-22</dc:date>
<dc:identifier>doi:10.1101/111013</dc:identifier>
<dc:title><![CDATA[An allosteric theory of transcription factor induction]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-02-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/112920v1?rss=1">
<title>
<![CDATA[
Genetic Analysis of a Metazoan Pathway using Transcriptomic Phenotypes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/112920v1?rss=1</link>
<description><![CDATA[
RNA-seq is commonly used to identify genetic modules that respond to perturbations. In single cells, transcriptomes have been used as phenotypes, but this concept has not been applied to whole-organism RNA-seq. Linear models can quantify expression effects of individual mutants and identify epistatic effects in double mutants. To make interpretation of these high-dimensional measurements intuitive, we developed a single coefficient to quantify transcriptome-wide epistasis that accurately reflects the underlying interactions. To demonstrate our approach, we sequenced four single and two double mutants of Caenorhabditis elegans. From these mutants, we reconstructed the known hypoxia pathway. In addition, we uncovered a class of 56 genes that have opposing changes in expression in egl-9(lf) compared to vhl-1(lf) but the egl-9(lf); vhl-1(lf) mutant has the same phenotype as egl-9(lf). This class violates the classical model of HIF-1 regulation, but can be explained by postulating a role of hydroxylated HIF-1 in transcriptional control.nnSignificance StatementTranscriptome profiling is a way to quickly and quantitatively measure gene expression level. Because of their quantitative nature, there is widespread interest in using transcriptomic profiles as a phenotype for genetic analysis. However, a source of major concern is that whole-animal transcriptomic profiles mix the expression signatures of multiple cellular states, making it hard to accurately reconstruct genetic interactions. Additionally, it has been difficult to quantify epistasis, the signature of genetic interaction between two genes, in these molecular phenotypes. Here, we show that it is possible to accurately reconstruct genetic interactions between genes using whole-animal RNA sequencing, and we demonstrate a powerful new way to measure and understand epistasis arising from these measurements. This suggests that whole-organism RNA-seq can be a powerful tool with which to understand genetic interactions in entire organisms and not only in isolated cells. With the advent of genome engineering tools, generating mutants has become easier and faster for many organisms. As mutants become easier to create, phenotyping them has become a major bottleneck in understanding the biological functions of the genes in question. Our work presents a possible solution to this problem, because transcriptome profiling is fast and sensitive to genetic perturbations regardless of the context they operate in.
]]></description>
<dc:creator>Angeles Albores, D.</dc:creator>
<dc:creator>Puckett Robinson, C.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2017-03-02</dc:date>
<dc:identifier>doi:10.1101/112920</dc:identifier>
<dc:title><![CDATA[Genetic Analysis of a Metazoan Pathway using Transcriptomic Phenotypes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-03-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/121202v1?rss=1">
<title>
<![CDATA[
The Human Cell Atlas 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/121202v1?rss=1</link>
<description><![CDATA[
The recent advent of methods for high-throughput single-cell molecular profiling has catalyzed a growing sense in the scientific community that the time is ripe to complete the 150-year-old effort to identify all cell types in the human body, by undertaking a Human Cell Atlas Project as an international collaborative effort. The aim would be to define all human cell types in terms of distinctive molecular profiles (e.g., gene expression) and connect this information with classical cellular descriptions (e.g., location and morphology). A comprehensive reference map of the molecular state of cells in healthy human tissues would propel the systematic study of physiological states, developmental trajectories, regulatory circuitry and interactions of cells, as well as provide a framework for understanding cellular dysregulation in human disease. Here we describe the idea, its potential utility, early proofs-of-concept, and some design considerations for the Human Cell Atlas.
]]></description>
<dc:creator>Regev, A.</dc:creator>
<dc:creator>Teichmann, S.</dc:creator>
<dc:creator>Lander, E. S.</dc:creator>
<dc:creator>Amit, I.</dc:creator>
<dc:creator>Benoist, C.</dc:creator>
<dc:creator>Birney, E.</dc:creator>
<dc:creator>Bodenmiller, B.</dc:creator>
<dc:creator>Campbell, P.</dc:creator>
<dc:creator>Carninci, P.</dc:creator>
<dc:creator>Clatworthy, M.</dc:creator>
<dc:creator>Clevers, H.</dc:creator>
<dc:creator>Deplancke, B.</dc:creator>
<dc:creator>Dunham, I.</dc:creator>
<dc:creator>Eberwine, J.</dc:creator>
<dc:creator>Eils, R.</dc:creator>
<dc:creator>Enard, W.</dc:creator>
<dc:creator>Farmer, A.</dc:creator>
<dc:creator>Fugger, L.</dc:creator>
<dc:creator>Gottgens, B.</dc:creator>
<dc:creator>Hacohen, N.</dc:creator>
<dc:creator>Haniffa, M.</dc:creator>
<dc:creator>Hemberg, M.</dc:creator>
<dc:creator>Kim, S. K.</dc:creator>
<dc:creator>Klenerman, P.</dc:creator>
<dc:creator>Kriegstein, A.</dc:creator>
<dc:creator>Lein, E.</dc:creator>
<dc:creator>Linnarsson, S.</dc:creator>
<dc:creator>Lundeberg, J.</dc:creator>
<dc:creator>Majumder, P.</dc:creator>
<dc:creator>Marioni, J.</dc:creator>
<dc:creator>Merad, M.</dc:creator>
<dc:creator>Mhlanga, M.</dc:creator>
<dc:creator>Nawijn, M.</dc:creator>
<dc:creator>Netea, M.</dc:creator>
<dc:creator>Nolan, G.</dc:creator>
<dc:creator>Pe'er, D.</dc:creator>
<dc:creator>Philipakis, A.</dc:creator>
<dc:creator>Ponting, C. P.</dc:creator>
<dc:creator>Quake, S. R.</dc:creator>
<dc:creator>Reik, W.</dc:creator>
<dc:creator>Rozenblatt-Rosen, O.</dc:creator>
<dc:creator>Sanes, J. R.</dc:creator>
<dc:creator>Satija, R.</dc:creator>
<dc:creator>Shumacher, T.</dc:creator>
<dc:creator>Shalek, A. K</dc:creator>
<dc:date>2017-05-08</dc:date>
<dc:identifier>doi:10.1101/121202</dc:identifier>
<dc:title><![CDATA[The Human Cell Atlas]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-05-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/127613v1?rss=1">
<title>
<![CDATA[
A general method to fine-tune fluorophores for live-cell and in vivo imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/127613v1?rss=1</link>
<description><![CDATA[
AO_SCPCAPBSTRACTC_SCPCAPPushing the frontier of fluorescence microscopy requires the design of enhanced fluorophores with finely tuned properties. We recently discovered that incorporation of four-membered azetidine rings into classic fluorophore structures elicits substantial increases in brightness and photostability, resulting in the  Janelia Fluor (JF) series of dyes. Here, we refine and extend this strategy, showing that incorporation of 3-substituted azetidine groups allows rational tuning of the spectral and chemical properties with unprecedented precision. This strategy yields a palette of new fluorescent and fluorogenic labels with excitation ranging from blue to the far-red with utility in live cells, tissue, and animals.
]]></description>
<dc:creator>Grimm, J. B.</dc:creator>
<dc:creator>Muthusamy, A. K.</dc:creator>
<dc:creator>Liang, Y.</dc:creator>
<dc:creator>Brown, T. A.</dc:creator>
<dc:creator>Lemon, W. C.</dc:creator>
<dc:creator>Patel, R.</dc:creator>
<dc:creator>Lu, R.</dc:creator>
<dc:creator>Macklin, J. J.</dc:creator>
<dc:creator>Keller, P. J.</dc:creator>
<dc:creator>Ji, N.</dc:creator>
<dc:creator>Lavis, L. D.</dc:creator>
<dc:date>2017-04-14</dc:date>
<dc:identifier>doi:10.1101/127613</dc:identifier>
<dc:title><![CDATA[A general method to fine-tune fluorophores for live-cell and in vivo imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-04-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/138834v1?rss=1">
<title>
<![CDATA[
Transcranial alternating current stimulation (tACS) mechanisms and protocols 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/138834v1?rss=1</link>
<description><![CDATA[
What if you could affect both neuroplasticity and human cognitive performance by parametrically modulating neural oscillations? Ongoing neuronal activity is susceptible to the modulation of synaptic activity and membrane potentials. This susceptibility leverages transcranial alternating current stimulation (tACS) for neuroplastic interventions. Through neuromodulation of phasic, neural activity, tACS presents a powerful tool for investigations of the neural correlates of cognition alongside other forms of transcranial electric stimulation (tES) and noninvasive brain stimulation (NIBS). The rapid pace of development in this area requires clarification of best practices. Here, we briefly introduce tACS dogma and review the most compelling findings from the tACS literature to provide a starting point for the use of tACS under research conditions.
]]></description>
<dc:creator>Tavakoli, A. V.</dc:creator>
<dc:creator>Yun, K.</dc:creator>
<dc:date>2017-05-17</dc:date>
<dc:identifier>doi:10.1101/138834</dc:identifier>
<dc:title><![CDATA[Transcranial alternating current stimulation (tACS) mechanisms and protocols]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-05-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/154351v1?rss=1">
<title>
<![CDATA[
The structural basis for regulation of the nucleo-cytoplasmic distribution of Bag6 by TRC35 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/154351v1?rss=1</link>
<description><![CDATA[
The metazoan protein BCL2-associated athanogene cochaperone 6 (Bag6) forms a hetero-trimeric complex with ubiquitin-like 4A (Ubl4A) and transmembrane domain recognition complex 35 (TRC35). This Bag6 complex is involved in tail-anchored protein targeting and various protein quality control pathways in the cytosol as well as regulating transcription and histone methylation in the nucleus. Here we present a crystal structure of Bag6 and its cytoplasmic retention factor TRC35, revealing that TRC35 is remarkably conserved throughout opisthokont lineage except at the C-terminal Bag6-binding groove, which evolved to accommodate a novel metazoan factor Bag6. Remarkably, while TRC35 and its fungal homolog guided entry of tail-anchored protein 4 (Get4) utilize a conserved hydrophobic patch to bind their respective C-terminal binding partners Bag6 and Get5, Bag6 wraps around TRC35 on the opposite face relative to the Get4-5 interface. We further demonstrate that the residues involved in TRC35 binding are not only critical for occluding the Bag6 nuclear localization sequence from karyopherin  binding to retain Bag6 in the cytosol, but also for preventing TRC35 from succumbing to RNF126-mediated ubiquitylation and degradation. The results provide a mechanism for regulation of Bag6 nuclear localization and the functional integrity of the Bag6 complex in the cytosol.
]]></description>
<dc:creator>Mock, J.-Y.</dc:creator>
<dc:creator>Xu, Y.</dc:creator>
<dc:creator>Ye, Y.</dc:creator>
<dc:creator>Clemons, W.</dc:creator>
<dc:date>2017-06-23</dc:date>
<dc:identifier>doi:10.1101/154351</dc:identifier>
<dc:title><![CDATA[The structural basis for regulation of the nucleo-cytoplasmic distribution of Bag6 by TRC35]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-06-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/156760v1?rss=1">
<title>
<![CDATA[
Diffusion as a ruler: modeling kinesin diffusion as a length sensor for intraflagellar transport 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/156760v1?rss=1</link>
<description><![CDATA[
An important question in cell biology is whether cells are able to measure size, either whole cell size or organelle size. Perhaps cells have an internal chemical representation of size that can be used to precisely regulate growth, or perhaps size is just an accident that emerges due to constraint of nutrients. The eukaryotic flagellum is an ideal model for studying size sensing and control because its linear geometry makes it essentially one-dimensional, greatly simplifying mathematical modeling. The assembly of flagella is regulated by intraflagellar transport (IFT), in which kinesin motors carry cargo adaptors for flagellar proteins along the flagellum and then deposit them at the tip, lengthening the flagellum. The rate at which IFT motors are recruited to begin transport into the flagellum is anticorrelated with the flagellar length, implying some kind of communication between the base and the tip and possibly indicating that cells contain some mechanism for measuring flagellar length. Although it is possible to imagine many complex scenarios in which additional signaling molecules sense length and carry feedback signals to the cell body to control IFT, might the already-known components of the IFT system be sufficient to allow length dependence of IFT? Here, we investigate a model in which the anterograde kinesin motors unbind after cargo delivery, diffuse back to the base, and are subsequently reused to power entry of new IFT trains into the flagellum. By modeling such a system at three different levels of abstraction we are able to show that the diffusion time of the motors can in principle be sufficient to serve as a proxy for length measurement. In all three implementations, we found that the diffusion model can not only achieve a stable steady-state length without the addition of any other signaling molecules or pathways, but also is able to produce the anticorrelation between length and IFT recruitment rate that has been observed in quantitative imaging studies.
]]></description>
<dc:creator>Hendel, N. L.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Marshall, W. F.</dc:creator>
<dc:date>2017-06-27</dc:date>
<dc:identifier>doi:10.1101/156760</dc:identifier>
<dc:title><![CDATA[Diffusion as a ruler: modeling kinesin diffusion as a length sensor for intraflagellar transport]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-06-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/190199v1?rss=1">
<title>
<![CDATA[
Gene-level differential analysis at transcript-level resolution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/190199v1?rss=1</link>
<description><![CDATA[
Gene-level differential expression analysis based on RNA-Seq is more robust, powerful and biologically actionable than transcript-level differential analysis. However aggregation of transcript counts prior to analysis results can mask transcript-level dynamics. We demonstrate that aggregating the results of transcript-level analysis allow for gene-level analysis with transcript-level resolution. We also show that p-value aggregation methods, typically used for meta-analyses, greatly increase the sensitivity of gene-level differential analyses. Furthermore, such aggregation can be applied directly to transcript compatibility counts obtained during pseudoalignment, thereby allowing for rapid and accurate model-free differential testing. The methods are general, allowing for testing not only of genes but also of any groups of transcripts, and we showcase an example where we apply them to perturbation analysis of gene ontologies.
]]></description>
<dc:creator>Yi, L.</dc:creator>
<dc:creator>Pimentel, H.</dc:creator>
<dc:creator>Bray, N. L.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2017-09-18</dc:date>
<dc:identifier>doi:10.1101/190199</dc:identifier>
<dc:title><![CDATA[Gene-level differential analysis at transcript-level resolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-09-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2019.12.13.876169v1?rss=1">
<title>
<![CDATA[
Gene drive and resilience through renewal with next generation Cleave and Rescue selfish genetic elements 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2019.12.13.876169v1?rss=1</link>
<description><![CDATA[
Gene drive-based strategies for modifying populations face the problem that genes encoding cargo and the drive mechanism are subject to separation, mutational inactivation, and loss of efficacy. Resilience, an ability to respond to these eventualities in ways that restore population modification with functional genes is needed for long-term success. Here we show that resilience can be achieved through cycles of population modification with "Cleave and Rescue" (ClvR) selfish genetic elements. ClvR comprises a DNA sequence-modifying enzyme such as Cas9/gRNAs that disrupts endogenous versions of an essential gene, and a recoded version of the essential gene resistant to cleavage. ClvR spreads by creating conditions in which those lacking ClvR die because they lack functional versions of the essential gene. Cycles of modification can in principal be carried out if two ClvR elements targeting different essential genes are located at the same genomic position, and one of them, ClvRn+1, carries a Rescue transgene from an earlier element, ClvRn. ClvRn+1 should spread within a population of ClvRn, while also bringing about a decrease in its frequency. To test this hypothesis we first show that multiple ClvRs, each targeting a different essential gene, function when located at a common chromosomal position in Drosophila. We then show that when several of these also carry the Rescue from a different ClvR, they spread to transgene fixation in populations fixed for the latter, and at its expense. Therefore, genetic modifications of populations can be overwritten with new content, providing an ongoing point of control.

SignificanceGene drive can spread beneficial traits through populations, but will never be a one-shot project in which one genetic element provides all desired modifications, for an indefinitely long time. Here we show that gene drive mediated population modification in Drosophila can be overwritten with new content while eliminating old, using Cleave and Rescue (ClvR) selfish genetic elements. The ability to carry out cycles of modification that create and then leave behind a minimal genetic footprint while entering and exiting a population provides important points of control. It makes possible the replacement of broken elements, upgrades with new elements that better carry out their tasks and/or provide new functions, all while promoting the removal of modifications no longer needed.
]]></description>
<dc:creator>Oberhofer, G.</dc:creator>
<dc:creator>Ivy, T.</dc:creator>
<dc:creator>Hay, B. A.</dc:creator>
<dc:date>2019-12-15</dc:date>
<dc:identifier>doi:10.1101/2019.12.13.876169</dc:identifier>
<dc:title><![CDATA[Gene drive and resilience through renewal with next generation Cleave and Rescue selfish genetic elements]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.01.18.910323v1?rss=1">
<title>
<![CDATA[
Deciphering the regulatory genome of Escherichiacoli, one hundred promoters at a time 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.01.18.910323v1?rss=1</link>
<description><![CDATA[
Advances in DNA sequencing have revolutionized our ability to read genomes. However, even in the most well-studied of organisms, the bacterium Escherichia coli, for {approx} 65% of the promoters we remain completely ignorant of their regulation. Until we have cracked this regulatory Rosetta Stone, efforts to read and write genomes will remain haphazard. We introduce a new method (Reg-Seq) linking a massively-parallel reporter assay and mass spectrometry to produce a base pair resolution dissection of more than 100 promoters in E. coli in 12 different growth conditions. First, we show that our method recapitulates regulatory information from known sequences. Then, we examine the regulatory architectures for more than 80 promoters in the E. coli genome which previously had no known regulation. In many cases, we also identify which transcription factors mediate their regulation. The method introduced here clears a path for fully characterizing the regulatory genome of model organisms, with the potential of moving on to an array of other microbes of ecological and medical relevance.
]]></description>
<dc:creator>Ireland, W. T. T.</dc:creator>
<dc:creator>Beeler, S. M.</dc:creator>
<dc:creator>Flores-Bautista, E.</dc:creator>
<dc:creator>Belliveau, N. M.</dc:creator>
<dc:creator>Sweredoski, M. J.</dc:creator>
<dc:creator>Moradian, A.</dc:creator>
<dc:creator>Kinney, J. B.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2020-01-18</dc:date>
<dc:identifier>doi:10.1101/2020.01.18.910323</dc:identifier>
<dc:title><![CDATA[Deciphering the regulatory genome of Escherichiacoli, one hundred promoters at a time]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-01-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.01.24.918748v1?rss=1">
<title>
<![CDATA[
New candidates for regulated gene integrity revealed through precise mapping of integrative genetic elements 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.01.24.918748v1?rss=1</link>
<description><![CDATA[
Integrative genetic elements (IGEs) are mobile multigene DNA units that integrate into and excise from host bacterial chromosomes. Each IGE usually targets a specific site within a conserved host gene, integrating in a manner that preserves target gene function. However, a small number of bacterial genes are known to be inactivated upon IGE integration and reactivated upon excision, regulating phenotypes of virulence, mutation rate, and terminal differentiation in multicellular bacteria. The list of regulated gene integrity (RGI) cases has been slow-growing because IGEs have been challenging to precisely and comprehensively locate in genomes. We present software (TIGER) that maps IGEs with unprecedented precision and without attB site bias. TIGER uses a comparative genomic, ping-pong BLAST approach, based on the principle that the IGE integration module (i.e., its int-attP region) is cohesive. The resultant IGEs, along with integrase phylogenetic analysis and gene inactivation tests, revealed 19 new cases of genes whose integrity is regulated by IGEs (including dut, eccCa1, gntT, hrpB, merA, ompN, prkA, tqsA, traG, yifB, yfaT and ynfE), as well as recovering previously known cases (in sigK, spsM, comK, mlrA, and hlb genes). It also recovered known clades of site-promiscuous integrases and identified possible new ones.
]]></description>
<dc:creator>Mageeney, C. M.</dc:creator>
<dc:creator>Lau, B. Y.</dc:creator>
<dc:creator>Wagner, J. M.</dc:creator>
<dc:creator>Hudson, C. M.</dc:creator>
<dc:creator>Schoeniger, J. S.</dc:creator>
<dc:creator>Krishnakumar, R.</dc:creator>
<dc:creator>Williams, K. P.</dc:creator>
<dc:date>2020-01-25</dc:date>
<dc:identifier>doi:10.1101/2020.01.24.918748</dc:identifier>
<dc:title><![CDATA[New candidates for regulated gene integrity revealed through precise mapping of integrative genetic elements]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-01-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.06.936641v1?rss=1">
<title>
<![CDATA[
Lateral gene transfer drives metabolic flexibility in the anaerobic methane oxidising archaeal family Methanoperedenaceae 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.06.936641v1?rss=1</link>
<description><![CDATA[
Anaerobic oxidation of methane (AOM) is an important biological process responsible for controlling the flux of methane into the atmosphere. Members of the archaeal family Methanoperedenaceae (formerly ANME-2d) have been demonstrated to couple AOM to the reduction of nitrate, iron, and manganese. Here, comparative genomic analysis of 16 Methanoperedenaceace metagenome-assembled genomes (MAGs), recovered from diverse environments, revealed novel respiratory strategies acquired through lateral gene transfer (LGT) events from diverse archaea and bacteria. Comprehensive phylogenetic analyses suggests that LGT has allowed members of the Methanoperedenaceae to acquire genes for the oxidation of hydrogen and formate, and the reduction of arsenate, selenate and elemental sulfur. Numerous membrane-bound multi-heme c type cytochrome complexes also appear to have been laterally acquired, which may be involved in the direct transfer of electrons to metal oxides, humics and syntrophic partners.

ImportanceAOM by microorganisms limits the atmospheric release of the potent greenhouse gas methane and has consequent importance to the global carbon cycle and climate change modelling. While the oxidation of methane coupled to sulphate by consortia of anaerobic methanotrophic (ANME) archaea and bacteria is well documented, several other potential electron acceptors have also been reported to support AOM. In this study we identify a number of novel respiratory strategies that appear to have been laterally acquired by members of the Methanoperedenaceae as they are absent in related archaea and other ANME lineages. Expanding the known metabolic potential for members of the Methanoperedenaceae provides important insight into their ecology and suggests their role in linking methane oxidation to several global biogeochemical cycles.
]]></description>
<dc:creator>McIlroy, S. J.</dc:creator>
<dc:creator>Leu, A. O.</dc:creator>
<dc:creator>Ye, J.</dc:creator>
<dc:creator>Parks, D. H.</dc:creator>
<dc:creator>Orphan, V.</dc:creator>
<dc:creator>Tyson, G. W.</dc:creator>
<dc:date>2020-02-06</dc:date>
<dc:identifier>doi:10.1101/2020.02.06.936641</dc:identifier>
<dc:title><![CDATA[Lateral gene transfer drives metabolic flexibility in the anaerobic methane oxidising archaeal family Methanoperedenaceae]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.02.09.940353v1?rss=1">
<title>
<![CDATA[
Aesthetic preference for art emerges from a weighted integration over hierarchically structured visual features in the brain 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.02.09.940353v1?rss=1</link>
<description><![CDATA[
It is an open question whether preferences for visual art can be lawfully predicted from the basic constituent elements of a visual image. Moreover, little is known about how such preferences are actually constructed in the brain. Here we developed and tested a computational framework to gain an understanding of how the human brain constructs aesthetic value. We show that it is possible to explain human preferences for a piece of art based on an analysis of features present in the image. This was achieved by analyzing the visual properties of drawings and photographs by multiple means, ranging from image statistics extracted by computer vision tools, subjective human ratings about attributes, to a deep convolutional neural network. Crucially, it is possible to predict subjective value ratings not only within but also across individuals, speaking to the possibility that much of the variance in human visual preference is shared across individuals. Neuroimaging data revealed that preference computations occur in the brain by means of a graded hierarchical representation of lower and higher level features in the visual system. These features are in turn integrated to compute an overall subjective preference in the parietal and prefrontal cortex. Our findings suggest that rather than being idiosyncratic, human preferences for art can be explained at least in part as a product of a systematic neural integration over underlying visual features of an image. This work not only advances our understanding of the brain-wide computations underlying value construction but also brings new mechanistic insights to the study of visual aesthetics and art appreciation.
]]></description>
<dc:creator>Iigaya, K.</dc:creator>
<dc:creator>Yi, S.</dc:creator>
<dc:creator>Wahle, I. A.</dc:creator>
<dc:creator>Tanwisuth, K.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:date>2020-02-10</dc:date>
<dc:identifier>doi:10.1101/2020.02.09.940353</dc:identifier>
<dc:title><![CDATA[Aesthetic preference for art emerges from a weighted integration over hierarchically structured visual features in the brain]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-02-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.03.14.991901v1?rss=1">
<title>
<![CDATA[
Dynamic changes in tRNA modifications and abundance during T-cell activation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.03.14.991901v1?rss=1</link>
<description><![CDATA[
The tRNA pool determines the efficiency, throughput, and accuracy of translation. Previous studies have identified dynamic changes in the tRNA supply and mRNA demand during cancerous proliferation. Yet, dynamic changes may occur also during physiologically normal proliferation, and these are less characterized. We examined the tRNA and mRNA pools of T-cells during their vigorous proliferation and differentiation upon triggering their antigen receptor. We observe a global signature of switch in demand for codons at the early proliferation phase of the response, accompanied by corresponding changes in tRNA expression levels. In the later phase, upon differentiation, the response of the tRNA pool is relaxed back to basal level, potentially restraining excessive proliferation. Sequencing of tRNAs allowed us to also evaluate their diverse base-modifications. We found that two types of tRNA modifications, wybutosine and ms2t6A, are reduced dramatically during T-cell activation. These modifications occur in the anti-codon loops of two tRNAs that decode "slippery codons", that are prone to ribosomal frameshifting. Attenuation of these frameshift-protective modifications is expected to increase the potential for proteome-wide frameshifting during T-cell proliferation. Indeed, human cell lines deleted of a wybutosine writer showed increased ribosomal frameshifting, as detected with a HIV gag-pol frameshifting site reporter. These results may explain HIVs specific tropism towards proliferating T-Cells since it requires ribosomal frameshift exactly on the corresponding codon for infection. The changes in tRNA expression and modifications uncover a new layer of translation regulation during T-cell proliferation and exposes a potential trade-off between cellular growth and translation fidelity.

Significance statementThe tRNA pool decodes genetic information during translation. As such, it is subject to intricate physiological regulation in all species, across different physiological conditions. Here we show for the first time a program that governs the tRNA pool and its interaction with the transcriptome upon a physiological cellular proliferation- T-cells activation. We found that upon antigenic activation of T-cells, their tRNA and mRNA pools undergo coordinated and complementary changes, which are relaxed when cells reduce back their proliferation rate and differentiate into memory cells. We found a reduction in two particular tRNA modifications that have a role in governing translation fidelity and frameshift prevention. This exposes a vulnerability in activated T-cells that may be utilized by HIV for its replication.

ClassificationBIOLOGICAL SCIENCES; cell biology
]]></description>
<dc:creator>Rak, R.</dc:creator>
<dc:creator>Polonsky, M.</dc:creator>
<dc:creator>Eizenberg, I.</dc:creator>
<dc:creator>Dahan, O.</dc:creator>
<dc:creator>Friedman, N.</dc:creator>
<dc:creator>Pilpel, Y. T.</dc:creator>
<dc:date>2020-03-15</dc:date>
<dc:identifier>doi:10.1101/2020.03.14.991901</dc:identifier>
<dc:title><![CDATA[Dynamic changes in tRNA modifications and abundance during T-cell activation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-03-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.13.092619v1?rss=1">
<title>
<![CDATA[
Convergent Antibody Responses to SARS-CoV-2 Infection in Convalescent Individuals 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.13.092619v1?rss=1</link>
<description><![CDATA[
During the COVID-19 pandemic, SARS-CoV-2 infected millions of people and claimed hundreds of thousands of lives. Virus entry into cells depends on the receptor binding domain (RBD) of the SARS-CoV-2 spike protein (S). Although there is no vaccine, it is likely that antibodies will be essential for protection. However, little is known about the human antibody response to SARS-CoV-21-5. Here we report on 149 COVID-19 convalescent individuals. Plasmas collected an average of 39 days after the onset of symptoms had variable half-maximal neutralizing titers ranging from undetectable in 33% to below 1:1000 in 79%, while only 1% showed titers >1:5000. Antibody cloning revealed expanded clones of RBD-specific memory B cells expressing closely related antibodies in different individuals. Despite low plasma titers, antibodies to three distinct epitopes on RBD neutralized at half-maximal inhibitory concentrations (IC50s) as low as single digit ng/mL. Thus, most convalescent plasmas obtained from individuals who recover from COVID-19 do not contain high levels of neutralizing activity. Nevertheless, rare but recurring RBD-specific antibodies with potent antiviral activity were found in all individuals tested, suggesting that a vaccine designed to elicit such antibodies could be broadly effective.
]]></description>
<dc:creator>Robbiani, D. F.</dc:creator>
<dc:creator>Gaebler, C.</dc:creator>
<dc:creator>Muecksch, F.</dc:creator>
<dc:creator>Cetrulo Lorenzi, J.</dc:creator>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>Cho, A.</dc:creator>
<dc:creator>Agudelo, M.</dc:creator>
<dc:creator>Barnes, C.</dc:creator>
<dc:creator>Finkin, S.</dc:creator>
<dc:creator>Hagglof, T.</dc:creator>
<dc:creator>Oliveira, T.</dc:creator>
<dc:creator>Viant, C.</dc:creator>
<dc:creator>Hurley, A.</dc:creator>
<dc:creator>Millard, K.</dc:creator>
<dc:creator>Kost, R.</dc:creator>
<dc:creator>Cipolla, M.</dc:creator>
<dc:creator>Gazumyan, A.</dc:creator>
<dc:creator>Gordon, K.</dc:creator>
<dc:creator>Bianchini, F.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Ramos, V.</dc:creator>
<dc:creator>Patel, R.</dc:creator>
<dc:creator>Dizon, J.</dc:creator>
<dc:creator>Shimeliovich, I.</dc:creator>
<dc:creator>Mendoza, P.</dc:creator>
<dc:creator>Hartweger, H.</dc:creator>
<dc:creator>Nogueira, L.</dc:creator>
<dc:creator>Pack, M.</dc:creator>
<dc:creator>Horowitz, J.</dc:creator>
<dc:creator>Schmidt, F.</dc:creator>
<dc:creator>Weisblum, Y.</dc:creator>
<dc:creator>Hoffmann, H.-H.</dc:creator>
<dc:creator>Michailidis, E.</dc:creator>
<dc:creator>Ashbrook, A.</dc:creator>
<dc:creator>Waltari, E. F.</dc:creator>
<dc:creator>Pak, J.</dc:creator>
<dc:creator>Huey-Tubman, K.</dc:creator>
<dc:creator>Koranda, N.</dc:creator>
<dc:creator>Hoffman, P.</dc:creator>
<dc:creator>West, A.</dc:creator>
<dc:creator>Rice, C.</dc:creator>
<dc:creator>Hatziioannou, T.</dc:creator>
<dc:creator>Bjorkman, P.</dc:creator>
<dc:creator>Bieniasz, P.</dc:creator>
<dc:creator>Caskey, M.</dc:creator>
<dc:creator>Nuss</dc:creator>
<dc:date>2020-05-15</dc:date>
<dc:identifier>doi:10.1101/2020.05.13.092619</dc:identifier>
<dc:title><![CDATA[Convergent Antibody Responses to SARS-CoV-2 Infection in Convalescent Individuals]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.18.102657v1?rss=1">
<title>
<![CDATA[
Human es-fMRI Resource: Concurrent deep-brain stimulation and whole-brain functional MRI 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.18.102657v1?rss=1</link>
<description><![CDATA[
Mapping the causal effects of one brain region on another (effective connectivity) is a challenging problem in neuroscience, since it requires invasive direct manipulation of brain function, together with whole-brain measurement of the effects produced. Here we establish a unique resource and present data from 26 human patients who underwent electrical stimulation during functional magnetic resonance imaging (es-fMRI). The patients had medically refractory epilepsy requiring surgically implanted intracranial electrodes in cortical and subcortical locations. One or multiple contacts on these electrodes were stimulated while simultaneously recording BOLD-fMRI activity in a block design. Multiple runs exist for patients with different stimulation sites. We describe the resource, data collection process, preprocessing using the fMRIPrep analysis pipeline and management of artifacts, and provide end-user analyses to visualize distal brain activation produced by site-specific electrical stimulation. The data are organized according to the brain imaging data structure (BIDS) specification, and are available for analysis or future dataset contributions on openneuro.org including both raw and preprocessed data.
]]></description>
<dc:creator>Thompson, W. H.</dc:creator>
<dc:creator>Nair, R.</dc:creator>
<dc:creator>Oya, H.</dc:creator>
<dc:creator>Esteban, O.</dc:creator>
<dc:creator>Shine, J. M.</dc:creator>
<dc:creator>Petkov, C.</dc:creator>
<dc:creator>Poldrack, R. A.</dc:creator>
<dc:creator>Howard, M.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:date>2020-05-20</dc:date>
<dc:identifier>doi:10.1101/2020.05.18.102657</dc:identifier>
<dc:title><![CDATA[Human es-fMRI Resource: Concurrent deep-brain stimulation and whole-brain functional MRI]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.05.21.108902v1?rss=1">
<title>
<![CDATA[
Heuristic Spike Sorting Tuner (HSST), a framework to determine optimal parameter selection for a generic spike sorting algorithm 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.05.21.108902v1?rss=1</link>
<description><![CDATA[
Bj[a]nes DA, Fisher LE, Gaunt RA, Weber DJHeuristic Spike Sorting Tuner (HSST), a framework to determine optimal parameter selection for a generic spike sorting algorithm. bioRxiv First published May 21, 2020. Extracellular microelectrodes frequently record neural activity from more than one neuron in the vicinity of the electrode. The process of labeling each recorded spike waveform with the identity of its source neuron is called spike sorting and is often approached from an abstracted statistical perspective. However, these approaches do not consider neurophysiological realities and may ignore important features that could improve the accuracy of these methods. Further, standard algorithms typically require selection of at least one free parameter, which can have significant effects on the quality of the output. We describe a Heuristic Spike Sorting Tuner (HSST) that determines the optimal choice of the free parameters for a given spike sorting algorithm based on the neurophysiological qualification of unit isolation and signal discrimination. A set of heuristic metrics are used to score the output of a spike sorting algorithm over a range of free parameters resulting in optimal sorting quality. We demonstrate that these metrics can be used to tune parameters in several spike sorting algorithms. The HSST algorithm shows robustness to variations in signal to noise ratio, number and relative size of units per channel. Moreover, the HSST algorithm is computationally efficient, operates unsupervised, and is parallelizable for batch processing.

NEW & NOTEWORTHYHSST incorporates known neurophysiological priors of extracellular neural recordings while simultaneously taking advantage of powerful abstract mathematical tools. Rather than simply selecting free parameters prior to running a sorting algorithm, HSST executes a sorting algorithm across a range of input parameters, using heuristic metrics to detect which spike-sorting output is most physiologically plausible. This novel approach enables unsupervised spike-sorting exceeding the performance of previous methods, thereby enabling the processing of large data sets with confidence.
]]></description>
<dc:creator>Bjanes, D.</dc:creator>
<dc:creator>Fisher, L. E.</dc:creator>
<dc:creator>Gaunt, R.</dc:creator>
<dc:creator>Weber, D.</dc:creator>
<dc:date>2020-05-25</dc:date>
<dc:identifier>doi:10.1101/2020.05.21.108902</dc:identifier>
<dc:title><![CDATA[Heuristic Spike Sorting Tuner (HSST), a framework to determine optimal parameter selection for a generic spike sorting algorithm]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-05-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.07.111930v1?rss=1">
<title>
<![CDATA[
What computational model provides the best explanation of face representations in the primate brain? 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.07.111930v1?rss=1</link>
<description><![CDATA[
Understanding how the brain represents the identity of complex objects is a central challenge of visual neuroscience. The principles governing object processing have been extensively studied in the macaque face patch system, a sub-network of inferotemporal (IT) cortex specialized for face processing. A previous study reported that single face patch neurons encode axes of a generative model called the "active appearance" model, which transforms 50-d feature vectors separately representing facial shape and facial texture into facial images. However, a systematic investigation comparing this model to other computational models, especially convolutional neural network models that have shown success in explaining neural responses in the ventral visual stream, has been lacking. Here, we recorded responses of cells in the most anterior face patch AM to a large set of real face images and compared a large number of models for explaining neural responses. We found that the active appearance model better explained responses than any other model except CORnet-Z, a feedforward deep neural network trained on general object classification to classify non-face images, whose performance it tied on some face image sets and exceeded on others. Surprisingly, deep neural networks trained specifically on facial identification did not explain neural responses well. A major reason is that units in the network, unlike neurons, are less modulated by face-related factors unrelated to facial identification such as illumination.
]]></description>
<dc:creator>Chang, L.</dc:creator>
<dc:creator>Egger, B.</dc:creator>
<dc:creator>Vetter, T.</dc:creator>
<dc:creator>Tsao, D.</dc:creator>
<dc:date>2020-06-08</dc:date>
<dc:identifier>doi:10.1101/2020.06.07.111930</dc:identifier>
<dc:title><![CDATA[What computational model provides the best explanation of face representations in the primate brain?]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.13.150292v1?rss=1">
<title>
<![CDATA[
Reconciling Kinetic and Equilibrium Models of Bacterial Transcription 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.13.150292v1?rss=1</link>
<description><![CDATA[
The study of transcription remains one of the centerpieces of modern biology with implications in settings from development to metabolism to evolution to disease. Precision measurements using a host of different techniques including fluorescence and sequencing readouts have raised the bar for what it means to quantitatively understand transcriptional regulation. In particular our understanding of the simplest genetic circuit is sufficiently refined both experimentally and theoretically that it has become possible to carefully discriminate between different conceptual pictures of how this regulatory system works. This regulatory motif, originally posited by Jacob and Monod in the 1960s, consists of a single transcriptional repressor binding to a promoter site and inhibiting transcription. In this paper, we show how seven distinct models of this so-called simple-repression motif, based both on equilibrium and kinetic thinking, can be used to derive the predicted levels of gene expression and shed light on the often surprising past success of the equilibrium models. These different models are then invoked to confront a variety of different data on mean, variance and full gene expression distributions, illustrating the extent to which such models can and cannot be distinguished, and suggesting a two-state model with a distribution of burst sizes as the most potent of the seven for describing the simple-repression motif.
]]></description>
<dc:creator>Morrison, M. J.</dc:creator>
<dc:creator>Razo-Mejia, M.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2020-06-14</dc:date>
<dc:identifier>doi:10.1101/2020.06.13.150292</dc:identifier>
<dc:title><![CDATA[Reconciling Kinetic and Equilibrium Models of Bacterial Transcription]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.06.29.178855v1?rss=1">
<title>
<![CDATA[
Secondary single-cell transcriptomic analysis reveals common molecular signatures of cerebrovascular injury between traumatic brain injury and aging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.06.29.178855v1?rss=1</link>
<description><![CDATA[
Cerebrovascular injury is a common pathological feature of a spectrum of neurological disorders including traumatic brain injury (TBI), stroke, Alzheimers disease (AD), as well as aging. Vascular manifestations among these conditions are similar indeed, including the breakdown of the blood-brain barrier (BBB). However, whether there is a common molecular mechanism underlying the vascular changes among these conditions remains elusive. Here, we report secondary transcriptomic analysis on cerebrovascular cells based single-cell RNA-seq datasets of mouse models of mild TBI and aging, with a focus on endothelial cells and pericytes. We identify several molecular signatures commonly found between mTBI and aging vasculature, including Adamts1, Rpl23a, Tmem252, Car4, Serpine2, and Ndnf in endothelial cells, and Rps29 and Sepp1 in pericytes. These markers may represent the shared endophenotype of microvascular injury and be considered as cerebrovascular injury responsive genes. Additionally, pathway analysis on differentially expressed genes demonstrated alterations in common pathways between mTBI and aging, including vascular development and extracellular matrix pathways in endothelial cells. Hence, our analysis suggests that cerebrovascular injury triggered by different neurological conditions may share common molecular signatures, which may only be detected at the single-cell transcriptome level.
]]></description>
<dc:creator>Guo, X.</dc:creator>
<dc:creator>Zhang, B.</dc:creator>
<dc:creator>Gomez-Pinilla, F.</dc:creator>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>Zhao, Z.</dc:creator>
<dc:date>2020-06-30</dc:date>
<dc:identifier>doi:10.1101/2020.06.29.178855</dc:identifier>
<dc:title><![CDATA[Secondary single-cell transcriptomic analysis reveals common molecular signatures of cerebrovascular injury between traumatic brain injury and aging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-06-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.09.196253v1?rss=1">
<title>
<![CDATA[
2-Locus ​ Cleave and Rescue ​ selfish elements harness a recombination rate-dependent generational clock for self limiting gene drive 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.09.196253v1?rss=1</link>
<description><![CDATA[
Self-limiting gene drive allows control over the spread and fate of linked traits. Cleave and Rescue (ClvR) elements create self-sustaining drive and comprise a DNA sequence-modifying enzyme (Cas9-gRNAs, Cleaver) that disrupts an essential gene, and a tightly linked, uncleavable version of the essential gene (Rescue). ClvR spreads by creating conditions in which those without it die because they lack essential gene function. We show that when ClvR is implemented in a 2-locus format, with key elements - Rescue (and Cargo), and Cas9 and/or gRNAs - located at different genomic positions, spread of the Rescue is self-limiting. Drive strength and duration are determined by a recombination rate-dependent generational clock, providing an important point of control for different ecological and regulatory contexts. We implement 2-locus ClvR in Drosophila. Rescue spreads to high frequency in a Cas9-dependent manner, while the frequency of Cas9 decreases, demonstrating transient drive and loss of future drive potential.
]]></description>
<dc:creator>Georg Oberhofer</dc:creator>
<dc:creator>Tobin Ivy</dc:creator>
<dc:creator>Bruce Hay</dc:creator>
<dc:date>2020-07-09</dc:date>
<dc:identifier>doi:10.1101/2020.07.09.196253</dc:identifier>
<dc:title><![CDATA[2-Locus ​ Cleave and Rescue ​ selfish elements harness a recombination rate-dependent generational clock for self limiting gene drive]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.07.21.214619v1?rss=1">
<title>
<![CDATA[
Experience-dependent plasticity in an innate social behavior is mediated by hypothalamic LTP 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.07.21.214619v1?rss=1</link>
<description><![CDATA[
All animals can perform certain survival behaviors without prior experience, suggesting a "hard wiring" of underlying neural circuits. Experience, however, can alter the expression of innate behaviors. Where in the brain and how such plasticity occurs remains largely unknown. Previous studies have established the phenomenon of "aggression training," in which the repeated experience of winning successive aggressive encounters across multiple days leads to increased aggressiveness. Here we show that this procedure also leads to long-term potentiation (LTP) at an excitatory synapse, derived from the Anterior Hippocampus/Posterior Medial amygdala (AHiPM), onto estrogen receptor 1-expressing (Esr1+) neurons in the ventrolateral subdivision of the ventromedial hypothalamus (VMHvl). We demonstrate further that the optogenetic induction of such LTP in vivo facilitates, while optogenetic long-term depression (LTD) diminishes, the behavioral effect of aggression training, implying a causal role for potentiation at AHiPMVMHvlEsr1 synapses in mediating the effect of this training. Interestingly, [~]25% of inbred C57BL/6 mice fail to respond to aggression training. We show that these individual differences are correlated both with lower levels of testosterone, relative to mice that respond to such training, and with a failure to exhibit LTP in vivo after aggression training. Administration of exogenous testosterone to such non-aggressive mice restores both behavioral and physiological plasticity in vivo. Together, these findings reveal that LTP at a hypothalamic circuit node mediates a form of experience-dependent plasticity in an innate social behavior, and a potential hormone-dependent basis for individual differences in such plasticity among genetically identical mice.

Significance StatementModification of instinctive behaviors occurs through experience, yet the mechanisms through which this happens have remained largely unknown. Recent studies have shown that potentiation of aggression, an innate behavior, can occur through repeated winning of aggressive encounters. Here we show that synaptic plasticity at a specific excitatory input to a hypothalamic cell population is correlated with, and required for, the expression of increasingly higher levels of aggressive behavior following successful aggressive experience. We additionally show that the amplitude and persistence of long-term potentiation at this synapse are influenced by serum testosterone, administration of which can normalize individual differences among genetically identical inbred mice, in the expression of intermale aggression.
]]></description>
<dc:creator>Stagkourakis, S.</dc:creator>
<dc:creator>Spigolon, G.</dc:creator>
<dc:creator>Liu, G.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:date>2020-07-22</dc:date>
<dc:identifier>doi:10.1101/2020.07.21.214619</dc:identifier>
<dc:title><![CDATA[Experience-dependent plasticity in an innate social behavior is mediated by hypothalamic LTP]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-07-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.03.234260v1?rss=1">
<title>
<![CDATA[
Non-canonical, potassium-driven cerebrospinal fluid clearance 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.03.234260v1?rss=1</link>
<description><![CDATA[
Cerebrospinal fluid (CSF) provides vital support for the brain. Abnormal CSF accumulation is deleterious for perinatal neurodevelopment, but how CSF leaves the brain during this critical period is unknown. We found in mice a postnatal neurodevelopmental transition phase featuring precipitous CSF K+ clearance, accompanied by water, through the choroid plexus (ChP). The period corresponds to a human fetal stage when canonical CSF clearance pathways have yet to form and congenital hydrocephalus begins to manifest. Unbiased ChP metabolic and ribosomal profiling highlighted this transition phase with increased ATP yield and activated energy-dependent K+ transporters, in particular the Na+-K+-Cl- and water cotransporter NKCC1. ChP-targeted NKCC1 overexpression enhanced K+-driven CSF clearance and enabled more permissive cerebral hydrodynamics. Moreover, ventriculomegaly in an obstructive hydrocephalus model was improved by ChP-targeted NKCC1 overexpression. Collectively, we identified K+-driven CSF clearance through ChP during a transient but critical neurodevelopmental phase, with translational value for pathologic conditions.
]]></description>
<dc:creator>Xu, H.</dc:creator>
<dc:creator>Fame, R. M.</dc:creator>
<dc:creator>Sadegh, C.</dc:creator>
<dc:creator>Sutin, J.</dc:creator>
<dc:creator>Naranjo, C.</dc:creator>
<dc:creator>Syau, D.</dc:creator>
<dc:creator>Cui, J.</dc:creator>
<dc:creator>Shipley, F. B.</dc:creator>
<dc:creator>Vernon, A.</dc:creator>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Holtzman, M. J.</dc:creator>
<dc:creator>Heiman, M.</dc:creator>
<dc:creator>Warf, B. C.</dc:creator>
<dc:creator>Lin, P.-Y.</dc:creator>
<dc:creator>Lehtinen, M. K.</dc:creator>
<dc:date>2020-08-04</dc:date>
<dc:identifier>doi:10.1101/2020.08.03.234260</dc:identifier>
<dc:title><![CDATA[Non-canonical, potassium-driven cerebrospinal fluid clearance]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.05.237990v1?rss=1">
<title>
<![CDATA[
A MATLAB Toolbox for Modeling Genetic Circuits in Cell-Free Systems 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.05.237990v1?rss=1</link>
<description><![CDATA[
We introduce a MATLAB based simulation toolbox, called txtlsim, for an E. coli based Transcription-Translation (TX-TL) system. This toolbox accounts for several cell-free related phenomena, such as resource loading, consumption, and degradation, and in doing so, models the dynamics of TX-TL reactions for the entire duration of batch-mode experiments. We use a Bayesian parameter inference approach to characterize the reaction rate parameters associated with the core transcription, translation and mRNA degradation mechanics of the toolbox, allowing it to reproduce constitutive mRNA and protien expression trajectories. We demonstrate the use of this characterized toolbox in a circuit behavior prediction case study for an incoherent feed-forward loop.
]]></description>
<dc:creator>Singhal, V.</dc:creator>
<dc:creator>Tuza, Z. A.</dc:creator>
<dc:creator>Sun, Z.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2020-08-05</dc:date>
<dc:identifier>doi:10.1101/2020.08.05.237990</dc:identifier>
<dc:title><![CDATA[A MATLAB Toolbox for Modeling Genetic Circuits in Cell-Free Systems]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.08.21.261974v1?rss=1">
<title>
<![CDATA[
Cryo-EM Structures of HIV-1 trimer bound to CD4-mimetics M48U1 and BNM-III-170 adopt a CD4-bound open conformation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.08.21.261974v1?rss=1</link>
<description><![CDATA[
Human Immunodeficiency Virus-1 (HIV-1), the causative agent of AIDS, impacts millions of people. Entry into target cells is mediated by the HIV-1 envelope (Env) glycoprotein interacting with host receptor CD4, which triggers conformational changes allowing binding to a coreceptor and subsequent membrane fusion. Small molecule or peptide CD4-mimetic drugs mimic CD4s Phe43 interaction with Env by inserting into the conserved Phe43 pocket on Env subunit gp120. Here, we present single-particle cryo-EM structures of CD4-mimetics BNM-III-170 and M48U1 bound to a BG505 native-like Env trimer plus the CD4-induced antibody 17b at 3.7[A] and 3.9[A] resolution, respectively. CD4-mimetic-bound BG505 exhibits canonical CD4-induced conformational changes including trimer opening, formation of the 4-stranded gp120 bridging sheet, displacement of the V1V2 loop, and formation of a compact and elongated gp41 HR1C helical bundle. We conclude that CD4-induced structural changes on both gp120 and gp41 Env subunits are induced by binding to the gp120 Phe43 pocket.
]]></description>
<dc:creator>Jette, C. A.</dc:creator>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Kirk, S. M.</dc:creator>
<dc:creator>Melillo, B.</dc:creator>
<dc:creator>Smith, A. B.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2020-08-22</dc:date>
<dc:identifier>doi:10.1101/2020.08.21.261974</dc:identifier>
<dc:title><![CDATA[Cryo-EM Structures of HIV-1 trimer bound to CD4-mimetics M48U1 and BNM-III-170 adopt a CD4-bound open conformation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.09.16.300731v1?rss=1">
<title>
<![CDATA[
Wild flies hedge their thermal preference bets in response to seasonal fluctuations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.09.16.300731v1?rss=1</link>
<description><![CDATA[
Fluctuating environmental pressures can challenge organisms by repeatedly shifting the optimum phenotype. Two contrasting evolutionary strategies to cope with these fluctuations are 1) evolution of the mean phenotype to follow the optimum (adaptive tracking) or 2) diversifying phenotypes so that at least some individuals have high fitness in the current fluctuation (bet-hedging). Bet-hedging could underlie stable differences in the behavior of individuals that are present even when genotype and environment are held constant. Instead of being simply  noise, behavioral variation across individuals may reflect an evolutionary strategy of phenotype diversification. Using geographically diverse wild-derived fly strains and high-throughput assays of individual preference, we tested whether thermal preference variation in Drosophila melanogaster could reflect a bet-hedging strategy. We also looked for evidence that populations from different regions differentially adopt bet-hedging or adaptive-tracking strategies. Computational modeling predicted regional differences in the relative advantage of bet-hedging, and we found patterns consistent with that in regional variation in thermal preference heritability. In addition, we found that temporal patterns in mean preference support bet-hedging predictions and that there is a genetic basis for thermal preference variability. Our empirical results point to bet-hedging in thermal preference as a potentially important evolutionary strategy in wild populations.
]]></description>
<dc:creator>Akhund-Zade, J.</dc:creator>
<dc:creator>Yoon, D.</dc:creator>
<dc:creator>Bangerter, A.</dc:creator>
<dc:creator>Polizos, N.</dc:creator>
<dc:creator>Campbell, M. K.</dc:creator>
<dc:creator>Soloshenko, A.</dc:creator>
<dc:creator>Zhang, T.</dc:creator>
<dc:creator>Wice, E.</dc:creator>
<dc:creator>Albright, A.</dc:creator>
<dc:creator>Narayanan, A.</dc:creator>
<dc:creator>Schmidt, P.</dc:creator>
<dc:creator>Saltz, J.</dc:creator>
<dc:creator>Ayroles, J.</dc:creator>
<dc:creator>Klein, M.</dc:creator>
<dc:creator>Bergland, A.</dc:creator>
<dc:creator>de Bivort, B.</dc:creator>
<dc:date>2020-09-20</dc:date>
<dc:identifier>doi:10.1101/2020.09.16.300731</dc:identifier>
<dc:title><![CDATA[Wild flies hedge their thermal preference bets in response to seasonal fluctuations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.02.324343v1?rss=1">
<title>
<![CDATA[
Benchmarking ensemble docking methods as a scientific outreach project 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.02.324343v1?rss=1</link>
<description><![CDATA[
The discovery of new drugs is a time consuming and expensive process. Methods such as virtual screening, which can filter out ineffective compounds from drug libraries prior to expensive experimental study, have become popular research topics. As the computational drug discovery community has grown, in order to benchmark the various advances in methodology, organizations such as the Drug Design Data Resource have begun hosting blinded grand challenges seeking to identify the best methods for ligand pose-prediction, ligand affinity ranking, and free energy calculations. Such open challenges offer a unique opportunity for researchers to partner with junior students (e.g., high school and undergraduate) to validate basic yet fundamental hypotheses considered to be uninteresting to domain experts. Here, we, a group of high school-aged students and their mentors, present the results of our participation in Grand Challenge 4 where we predicted ligand affinity rankings for the Cathepsin S protease, an important protein target for autoimmune diseases. To investigate the effect of incorporating receptor dynamics on ligand affinity rankings, we employed the Relaxed Complex Scheme, a molecular docking method paired with molecular dynamics-generated receptor conformations. We found that CatS is a difficult target for molecular docking and we explore some advanced methods such as distance-restrained docking to try to improve the correlation with experiments. This project has exemplified the capabilities of high school students when supported with a rigorous curriculum, and demonstrates the value of community-driven competitions for beginners in computational drug discovery.
]]></description>
<dc:creator>Gan, J. L.</dc:creator>
<dc:creator>Kumar, D.</dc:creator>
<dc:creator>Chen, C.</dc:creator>
<dc:creator>Taylor, B. C.</dc:creator>
<dc:creator>Jagger, B. R.</dc:creator>
<dc:creator>Amaro, R. E.</dc:creator>
<dc:creator>Lee, C. T.</dc:creator>
<dc:date>2020-10-04</dc:date>
<dc:identifier>doi:10.1101/2020.10.02.324343</dc:identifier>
<dc:title><![CDATA[Benchmarking ensemble docking methods as a scientific outreach project]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.13.338137v1?rss=1">
<title>
<![CDATA[
Robotic Multi-Probe-Single-Actuator Inchworm Neural Microdrive 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.13.338137v1?rss=1</link>
<description><![CDATA[
Electrophysiology is one of the major experimental techniques used in neuroscience. The favorable spatial and temporal resolution as well as the increasingly larger site counts of brain recording electrodes contribute to the popularity and importance of electrophysiology in neuroscience. Such electrodes are typically mechanically placed in the brain to perform acute or chronic freely moving animal measurements. The micro positioners currently used for such tasks employ a single translator per independent probe being placed into the targeted brain region, leading to significant size and weight restrictions. To overcome this limitation, we have developed a miniature robotic multi-probe neural microdrive that utilizes novel phase-change-material-filled resistive heater micro-grippers. The microscopic dimensions, gentle gripping action, independent electronic actuation control, and high packing density of the grippers allow for micrometer-precision independent positioning of multiple arbitrarily shaped parallel neural electrodes with only a single piezo actuator in an inchworm motor configuration. This multi-probe-single-actuator design allows for significant size and weight reduction, as well as remote control and potential automation of the microdrive. We demonstrate accurate placement of multiple independent recording electrodes into the CA1 region of the rat hippocampus in vivo in acute and chronic settings. Thus, our robotic neural microdrive technology is applicable towards basic neuroscience and clinical studies, as well as other multi-probe or multi-sensor micro-positioning applications.

One Sentence SummaryMiniature robotic multi-probe single-actuator microdrive utilizing phase change material based micro-grippers.
]]></description>
<dc:creator>Smith, R. D.</dc:creator>
<dc:creator>Kolb, I.</dc:creator>
<dc:creator>Tanaka, S.</dc:creator>
<dc:creator>Lee, A. K.</dc:creator>
<dc:creator>Harris, T. D.</dc:creator>
<dc:creator>Barbic, M.</dc:creator>
<dc:date>2020-10-16</dc:date>
<dc:identifier>doi:10.1101/2020.10.13.338137</dc:identifier>
<dc:title><![CDATA[Robotic Multi-Probe-Single-Actuator Inchworm Neural Microdrive]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.10.14.340026v1?rss=1">
<title>
<![CDATA[
Convergence of a common solution to broad ebolavirus neutralization by glycan cap directed human antibodies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.10.14.340026v1?rss=1</link>
<description><![CDATA[
Antibodies that target the glycan cap epitope on ebolavirus glycoprotein (GP) are common in the adaptive response of survivors. A subset is known to be broadly neutralizing, but the details of their epitopes and basis for neutralization is not well-understood. Here we present cryo-electron microscopy (cryo-EM) structures of several glycan cap antibodies that variably synergize with GP base-binding antibodies. These structures describe a conserved site of vulnerability that anchors the mucin-like domains (MLD) to the glycan cap, which we name the MLD-anchor and cradle. Antibodies that bind to the MLD-cradle share common features, including the use of IGHV1-69 and IGHJ6 germline genes, which exploit hydrophobic residues and form beta-hairpin structures to mimic the MLD-anchor, disrupt MLD attachment, destabilize GP quaternary structure and block cleavage events required for receptor binding. Our results collectively provide a molecular basis for ebolavirus neutralization by broadly reactive glycan cap antibodies.
]]></description>
<dc:creator>Murin, C. D.</dc:creator>
<dc:creator>Gilchuk, P.</dc:creator>
<dc:creator>Ilinykh, P.</dc:creator>
<dc:creator>Huang, K.</dc:creator>
<dc:creator>Kuzmina, N.</dc:creator>
<dc:creator>Shen, X.</dc:creator>
<dc:creator>Brunh, J. F.</dc:creator>
<dc:creator>Brunh, A. L.</dc:creator>
<dc:creator>Davidson, E.</dc:creator>
<dc:creator>Doranz, B.</dc:creator>
<dc:creator>Williamson, L. E.</dc:creator>
<dc:creator>Copps, J.</dc:creator>
<dc:creator>Alkutkar, T.</dc:creator>
<dc:creator>Flyak, A. I.</dc:creator>
<dc:creator>Bukreyev, A.</dc:creator>
<dc:creator>Crowe, J. E.</dc:creator>
<dc:creator>Ward, A. B.</dc:creator>
<dc:date>2020-10-14</dc:date>
<dc:identifier>doi:10.1101/2020.10.14.340026</dc:identifier>
<dc:title><![CDATA[Convergence of a common solution to broad ebolavirus neutralization by glycan cap directed human antibodies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.10.376913v1?rss=1">
<title>
<![CDATA[
The embryonic node functions as an instructive stem cell niche 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.10.376913v1?rss=1</link>
<description><![CDATA[
In warm-blooded vertebrate embryos (mammals and birds), the body forms from a growth zone at the tail end. Hensens node, a region which induces and patterns the neural axis is located within this growth zone. The node also contains the precursors of neural, mesodermal and endodermal structures along the midline and has been suggested to contain a small population of resident stem cells. However, it is unknown whether the rest of the node constitutes an instructive stem cell niche, specifying stem cell behaviour. Here we combine transplantation of a single cell in vivo with single-cell mRNA sequencing in the chick and show that when made to enter the node, non-node-progenitor cells become resident and gain stem cell behaviour. These cells preferentially express G2/M phase cell-cycle related genes and are concentrated in posterior sub-regions of the node. The posterior part of the node therefore behaves as an instructive stem cell niche. These results demonstrate a new function for the vertebrate node during development.
]]></description>
<dc:creator>Solovieva, T.</dc:creator>
<dc:creator>Lu, H.-C.</dc:creator>
<dc:creator>Moverley, A.</dc:creator>
<dc:creator>Plachta, N.</dc:creator>
<dc:creator>Stern, C. D.</dc:creator>
<dc:date>2020-11-11</dc:date>
<dc:identifier>doi:10.1101/2020.11.10.376913</dc:identifier>
<dc:title><![CDATA[The embryonic node functions as an instructive stem cell niche]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.11.14.383141v1?rss=1">
<title>
<![CDATA[
osr1 couples intermediate mesoderm cell fate with temporal dynamics of vessel progenitor cell differentiation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.11.14.383141v1?rss=1</link>
<description><![CDATA[
Transcriptional regulatory networks refine gene expression boundaries throughout embryonic development to define the precise dimensions of organ progenitor territories. Kidney progenitors originate within the intermediate mesoderm (IM), but the pathways that establish the boundary between the IM and its neighboring vessel progenitors are poorly understood. Here, we delineate new roles for the zinc finger transcription factor Osr1 in kidney and vessel progenitor development. Zebrafish osr1 mutants display decreased IM formation and premature emergence of neighboring lateral vessel progenitors (LVPs). These phenotypes contrast with the increased IM and absent LVPs observed with loss of the bHLH transcription factor Hand2, and loss of hand2 partially suppresses the osr1 mutant phenotypes. hand2 and osr1 are both expressed in the posterior lateral mesoderm, but osr1 expression decreases dramatically prior to LVP emergence. Overexpressing osr1 inhibits LVP development while enhancing IM formation. Together, our data demonstrate that osr1 modulates both the extent of IM formation and the temporal dynamics of LVP development, suggesting that a balance between levels of osr1 and hand2 expression is essential to demarcate the dimensions of kidney and vessel progenitor territories.

SUMMARY STATEMENTAnalysis of the osr1 mutant phenotype reveals roles in determining the extent of intermediate mesoderm formation while inhibiting premature differentiation of neighboring vessel progenitors.
]]></description>
<dc:creator>Perens, E.</dc:creator>
<dc:creator>Diaz, J.</dc:creator>
<dc:creator>Quesnel, A.</dc:creator>
<dc:creator>Askary, A.</dc:creator>
<dc:creator>Crump, G.</dc:creator>
<dc:creator>Yelon, D.</dc:creator>
<dc:date>2020-11-15</dc:date>
<dc:identifier>doi:10.1101/2020.11.14.383141</dc:identifier>
<dc:title><![CDATA[osr1 couples intermediate mesoderm cell fate with temporal dynamics of vessel progenitor cell differentiation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.12.10.420141v1?rss=1">
<title>
<![CDATA[
Molecular evolutionary trends and biosynthesis pathways in the Oribatida revealed by the genome of Archegozetes longisetosus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.12.10.420141v1?rss=1</link>
<description><![CDATA[
Oribatid mites are a specious order of microarthropods within the subphylum Chelicerata, compromising about 11,000 described species. They are ubiquitously distributed across different microhabitats in all terrestrial ecosystems around the world and were among the first animals colonizing terrestrial habitats as decomposers and scavengers. Despite their species richness and ecological importance genomic resources are lacking for oribatids. Here, we present a 190-Mb genome assembly of the clonal, all-female oribatid mite species Archegozetes longisetosus Aoki, a model species used by numerous laboratories for the past 30 years. Comparative genomic and transcriptional analyses revealed patterns of reduced body segmentation and loss of segmental identity gene abd-A within Acariformes, and unexpected expression of key eye development genes in these eyeless mites across developmental stages. Consistent with their soil dwelling lifestyle, investigation of the sensory genes revealed a species-specific expansion of gustatory receptors, the largest chemoreceptor family in the genome used in olfaction, and evidence of horizontally transferred enzymes used in cell wall degradation of plant and fungal matter, both components of the A. longisetosus diet. Oribatid mites are also noted for their biosynthesis capacities and biochemical diversity. Using biochemical and genomic data, we were able to delineate the backbone biosynthesis of monoterpenes, an important class of compounds found in the major exocrine gland system of Oribatida - the oil glands. Given the mites strength as an experimental model, the new high-quality resources provided here will serve as the foundation for molecular research in Oribatida and will enable a broader understanding of chelicerate evolution.
]]></description>
<dc:creator>Brueckner, A.</dc:creator>
<dc:creator>Barnett, A. A.</dc:creator>
<dc:creator>Antoshechkin, I. A.</dc:creator>
<dc:creator>Kitchen, S. A.</dc:creator>
<dc:date>2020-12-11</dc:date>
<dc:identifier>doi:10.1101/2020.12.10.420141</dc:identifier>
<dc:title><![CDATA[Molecular evolutionary trends and biosynthesis pathways in the Oribatida revealed by the genome of Archegozetes longisetosus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-12-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.12.11.421891v1?rss=1">
<title>
<![CDATA[
Benzoquinones in the defensive secretion of a bug (Pamillia behrensii): a common chemical trait retrieved in the Heteroptera 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.12.11.421891v1?rss=1</link>
<description><![CDATA[
Benzoquinones are a phylogenetically widespread compound class within arthropods, appearing in harvestman, millipedes and insects. Whereas the function of benzoquinones as defensive compounds against potential predators and microbes has been well established, the full extent of benzoquinone usage across arthropods, and especially within Insecta, has yet to be established. Adding to the growing list of unique evolutionary origins of benzoquinone employment, we describe in this paper the metathoracic scent gland secretion of the mirid bug Pamillia behrensii, which is composed of heptan-2-one, 2-heptyl acetate, 2,3-dimethyl-1-4-benzoquinone, 2,3-dimethyl-1-4-hydroquinone as well as one unknown compound. Similarly, to many other arthropods that use benzoquinones, Pamillia releases the contents of its gland as a defensive mechanism in response to harassment by other arthropod predators. Morphological investigation of the gland showed that the benzoquinone-producing gland complex of P. behrensii follows a similar blueprint to metathoracic scent glands described in other Heteropterans. Overall, our data further underpins the widespread convergent evolution and use of benzoquinones for defense across the Arthropoda, now including the order Hemiptera.
]]></description>
<dc:creator>Wagner, J. M.</dc:creator>
<dc:creator>Naragon, T. H.</dc:creator>
<dc:creator>Brueckner, A.</dc:creator>
<dc:date>2020-12-12</dc:date>
<dc:identifier>doi:10.1101/2020.12.11.421891</dc:identifier>
<dc:title><![CDATA[Benzoquinones in the defensive secretion of a bug (Pamillia behrensii): a common chemical trait retrieved in the Heteroptera]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-12-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2020.12.18.423556v1?rss=1">
<title>
<![CDATA[
Analysis of Circuits for Dosage Control in Microbial Populations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2020.12.18.423556v1?rss=1</link>
<description><![CDATA[
Designing genetic circuits to control the behaviors of microbial populations is an ongoing challenge in synthetic biology. Here we analyze circuits which implement dosage control by controlling levels of a global signal in a microbial population in face of varying cell density, growth rate, and environmental dilution. We utilize the Lux quorum sensing system to implement dosage control circuits, and we analyze the dynamics of circuits using both simplified analytical analysis and in silico simulations. We demonstrate that strong negative feedback through inhibiting LuxI synthase expression along with AiiA degradase activity results in circuits with fast response times and robustness to cell density and dilution rate. We find that degradase activity yields robustness to variations in population density for large population sizes, while negative feedback to synthase production decreases sensitivity to dilution rates.
]]></description>
<dc:creator>Walton, S. J.</dc:creator>
<dc:creator>Clamons, S. E.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2020-12-20</dc:date>
<dc:identifier>doi:10.1101/2020.12.18.423556</dc:identifier>
<dc:title><![CDATA[Analysis of Circuits for Dosage Control in Microbial Populations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-12-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.14.426746v1?rss=1">
<title>
<![CDATA[
Mice in a labyrinth: Rapid learning, sudden insight, and efficient exploration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.14.426746v1?rss=1</link>
<description><![CDATA[
Animals learn certain complex tasks remarkably fast, sometimes after a single experience. What behavioral algorithms support this efficiency? Many contemporary studies based on two-alternative-forced-choice (2AFC) tasks observe only slow or incomplete learning. As an alternative, we study the unconstrained behavior of mice in a complex labyrinth and measure the dynamics of learning and the behaviors that enable it. A mouse in the labyrinth makes ~2000 navigation decisions per hour. The animal quickly discovers the location of a reward in the maze and executes correct 10-bit choices after only 10 reward experiences - a learning rate 1000-fold higher than in 2AFC experiments. Many mice improve discontinuously from one minute to the next, suggesting moments of sudden insight about the structure of the labyrinth. The underlying search algorithm does not require a global memory of places visited and is largely explained by purely local turning rules.
]]></description>
<dc:creator>Rosenberg, M.</dc:creator>
<dc:creator>Zhang, T.</dc:creator>
<dc:creator>Perona, P.</dc:creator>
<dc:creator>Meister, M.</dc:creator>
<dc:date>2021-01-15</dc:date>
<dc:identifier>doi:10.1101/2021.01.14.426746</dc:identifier>
<dc:title><![CDATA[Mice in a labyrinth: Rapid learning, sudden insight, and efficient exploration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.01.28.428674v1?rss=1">
<title>
<![CDATA[
The coral symbiont Candidatus Aquarickettsia is variably abundant in threatened Caribbean acroporids and transmitted horizontally. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.01.28.428674v1?rss=1</link>
<description><![CDATA[
The aquatic symbiont "Candidatus Aquarickettsia rohweri" infects a diversity of non-bilaterian metazoan phyla. In the threatened coral Acropora cervicornis, Aquarickettsia proliferates in response to increased nutrient exposure, resulting in suppressed growth and increased disease susceptibility and mortality. This study evaluated the extent, as well as the ecology and evolution of Aquarickettsia infecting the Caribbean corals: Ac. cervicornis and Ac. palmata and their hybrid ( Ac. prolifera). The bacterial parasite Aquarickettsia was found in all acroporids, with host and sampling location impacting infection magnitude. Phylogenomic and genome-wide single nucleotide variant analysis found Aquarickettsia clustering by region, not by coral taxon. Fixation analysis suggested within coral colonies, Aquarickettsia are genetically isolated to the extent that reinfection is unlikely. Relative to other Rickettsiales, Aquarickettsia is undergoing positive selection, with Florida populations experiencing greater positive selection relative to the other Caribbean locations. This may be due to Aquarickettsia response to increased nutrient stress in Florida, as indicated by greater in situ replication rates in these corals. Aquarickettsia did not significantly codiversify with either coral animal nor algal symbiont, and qPCR analysis of gametes and juveniles from susceptible coral genotypes indicated absence in early life stages. Thus, despite being an obligate parasite, Aquarickettsia must be horizontally transmitted via coral mucocytes, an unidentified secondary host, or a yet unexplored environmentally mediated mechanism. Importantly, the prevalence of Aquarickettsia in Ac. cervicornis and high abundance in Florida populations suggests that disease mitigation efforts in the US and Caribbean should focus on preventing early infection via horizontal transmission.
]]></description>
<dc:creator>Baker, L. J.</dc:creator>
<dc:creator>Reich, H. G.</dc:creator>
<dc:creator>Kitchen, S. A.</dc:creator>
<dc:creator>Klinges, J. G.</dc:creator>
<dc:creator>Koch, H. R.</dc:creator>
<dc:creator>Baums, I. B.</dc:creator>
<dc:creator>Muller, E.</dc:creator>
<dc:creator>Vega Thurber, R.</dc:creator>
<dc:date>2021-01-29</dc:date>
<dc:identifier>doi:10.1101/2021.01.28.428674</dc:identifier>
<dc:title><![CDATA[The coral symbiont Candidatus Aquarickettsia is variably abundant in threatened Caribbean acroporids and transmitted horizontally.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-01-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.10.434835v1?rss=1">
<title>
<![CDATA[
Discovery of Dynamical Network Models for Genetic Circuits from Time-Series Data with Incomplete Measurements 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.10.434835v1?rss=1</link>
<description><![CDATA[
Synthetic gene networks are frequently conceptualized and visualized as static graphs. This view of biological programming stands in stark contrast to the transient nature of biomolecular interaction, which is frequently enacted by labile molecules that are often unmeasured. Thus, the network topology and dynamics of synthetic gene networks can be difficult to verify in vivo or in vitro, due to the presence of unmeasured biological states. Here we introduce the dynamical structure function as a new mesoscopic, data-driven class of models to describe gene networks with incomplete measurements. We introduce a network reconstruction algorithm and a code base for reconstructing the dynamical structure function from data, to enable discovery and visualization of graphical relationships in a genetic circuit diagram as time-dependent functions rather than static, unknown weights. We prove a theorem, showing that dynamical structure functions can provide a data-driven estimate of the size of crosstalk fluctuations from an idealized model. We illustrate this idea with numerical examples. Finally, we show how data-driven estimation of dynamical structure functions can explain failure modes in two experimentally implemented genetic circuits, a historical genetic circuit and a new E. coli based transcriptional event detector.
]]></description>
<dc:creator>Yeung, E.</dc:creator>
<dc:creator>Kim, J.</dc:creator>
<dc:creator>Yuan, Y.</dc:creator>
<dc:creator>Goncalves, J.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2021-03-10</dc:date>
<dc:identifier>doi:10.1101/2021.03.10.434835</dc:identifier>
<dc:title><![CDATA[Discovery of Dynamical Network Models for Genetic Circuits from Time-Series Data with Incomplete Measurements]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.11.434917v1?rss=1">
<title>
<![CDATA[
kinesin recruitment by adapter SKIP on melanosomes is dynamically controlled by LC3B phosphorylation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.11.434917v1?rss=1</link>
<description><![CDATA[
Anterograde melanosome transport is essential for adaptive skin tanning response. However, the molecular components involved, their interplay and regulation by external cues in melanosome transport remain under-explored. Silencing of kinesin motors revealed that several members including the established KIF5B and a novel candidate KIF1B, mediate melanosome movement. The camouflage behaviour of zebrafish embryos induced by incident light or  -MSH requires kif1b, suggesting a conserved melanosome transport machinery across vertebrates. Interestingly, the peri-nuclear melanosome accumulation upon kinesin knockdown is recapitulated by the silencing of autophagy effector MAP1LC3B (LC3B). Pull-down assays identified KIF1B, but not KIF5B, to be the LC3B-associated kinesin. LC3B binds the adapter SKIP via its LIR docking region that is proximal to Thr12 residue, a site for phosphorylation by Protein Kinase A. We demonstrate that phosphorylation of LC3B at Thr12 is stimulated by -MSH, which potentiates the anterograde melanosome transport. Thereby, our study, identifies a novel kinesin motor KIF1B for melanosome movement and establishes LC3B as the key molecular component that facilitates -MSH responsive mobilization of melanosomes.

Key HighlightsO_LIKinesin screen reveals non-redundant use of KIF5B, KIF1B motors for melanosome transport
C_LIO_LIkif1b is required for camouflage response in zebrafish and melanosome movement in mammals
C_LIO_LIN-terminal region of LC3B interacts with adapter SKIP and couples kinesin KIF1B
C_LIO_LI-MSH activates PKA-mediated phosphorylation of LC3B to potentiate anterograde movement
C_LI

SignificanceMelanosomes are lysosome related organelles containing melanin pigment, that are synthesized in melanocytes and transferred to the recipient keratinocytes of skin. This involves long range melanosome movement within melanocytes to reach cell periphery for the transfer to follow. Physiologically, UV protection involves local secretion of melanocyte stimulating hormone (-MSH) that acts on melanocytes to promote skin tanning response. Herein, we investigate the components involved in this process and establish that the melanosome movement is dynamically controlled by -MSH through phosphorylation of LC3B. These findings establish the mechanism behind the rapid distribution of melanosomes during tanning response and provide opportunity to intervene for sun protection.
]]></description>
<dc:creator>Subramaniam, Y. J.</dc:creator>
<dc:creator>Murthy, D.</dc:creator>
<dc:creator>Raja, A. D.</dc:creator>
<dc:creator>Ramkumar, A.</dc:creator>
<dc:creator>Sivasubbu, S.</dc:creator>
<dc:creator>McEwan, D. G.</dc:creator>
<dc:creator>Gokhale, R. S.</dc:creator>
<dc:creator>Natarajan, V.</dc:creator>
<dc:date>2021-03-12</dc:date>
<dc:identifier>doi:10.1101/2021.03.11.434917</dc:identifier>
<dc:title><![CDATA[kinesin recruitment by adapter SKIP on melanosomes is dynamically controlled by LC3B phosphorylation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.12.435023v1?rss=1">
<title>
<![CDATA[
The geometry of face memory 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.12.435023v1?rss=1</link>
<description><![CDATA[
The ability to recognize familiar visual objects is critical to survival. A central assumption of neuroscience is that long-term memories are represented by the same brain areas that encode sensory stimuli (1). Neurons in inferotemporal (IT) cortex represent the sensory percept of visual objects using a distributed axis code (2-4). Whether and how the same IT neural population represents the long-term memory of visual objects remains unclear. Here, we examined how familiar faces are encoded in face patch AM and perirhinal cortex. We found that familiar faces were represented in a distinct subspace from unfamiliar faces. The familiar face subspace was shifted relative to the unfamiliar face subspace at short latency and then distorted to increase neural distances between familiar faces at long latency. This distortion enabled markedly improved discrimination of familiar faces in both AM and PR. Inactivation of PR did not affect these memory traces in AM, suggesting that the memory traces arise from intrinsic recurrent processes within IT cortex or interactions with downstream regions outside the medial temporal lobe (5, 6). Overall, our results reveal that memories of familiar faces are represented in IT and perirhinal cortex by a distinct long-latency code that is optimized to distinguish familiar identities.
]]></description>
<dc:creator>She, L.</dc:creator>
<dc:creator>Benna, M. K.</dc:creator>
<dc:creator>Shi, Y.</dc:creator>
<dc:creator>Fusi, S.</dc:creator>
<dc:creator>Tsao, D. Y.</dc:creator>
<dc:date>2021-03-12</dc:date>
<dc:identifier>doi:10.1101/2021.03.12.435023</dc:identifier>
<dc:title><![CDATA[The geometry of face memory]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.03.17.435265v1?rss=1">
<title>
<![CDATA[
Antibody elicited by HIV-1 immunogen vaccination in macaques displaces Env fusion peptide and destroys a neutralizing epitope 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.03.17.435265v1?rss=1</link>
<description><![CDATA[
HIV-1 vaccine design aims to develop an immunogen that elicits broadly neutralizing antibodies against a desired epitope, while eliminating responses to off-target regions of HIV-1 Env. Here we report isolation and characterization of Ab1245, an off-target antibody against the Env gp120-gp41 interface, from V3-glycan patch immunogen-primed and boosted macaques. A 3.7[A] cryo-EM structure of an Ab1245-Env complex reveals one Ab1245 Fab binding asymmetrically to Env trimer at the gp120-gp41 interface using its long CDRH3 to mimic regions of gp41. The mimicry includes positioning of a CDRH3 methionine into the gp41 tryptophan clasp, resulting in displacement of the fusion peptide and fusion peptide-proximal region. Despite fusion peptide displacement, Ab1245 is non-neutralizing even at high concentrations, implying that only two fusion peptides per trimer are required for viral-host membrane fusion. These structural analyses facilitate immunogen design to prevent elicitation of Ab1245-like antibodies that block neutralizing antibodies against the fusion peptide.
]]></description>
<dc:creator>Abernathy, M. E.</dc:creator>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>Vielmetter, J.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>Gnanapragasam, P. N.</dc:creator>
<dc:creator>Lee, Y. E.</dc:creator>
<dc:creator>Escolano, A.</dc:creator>
<dc:creator>Gautam, R.</dc:creator>
<dc:creator>Seaman, M. S.</dc:creator>
<dc:creator>Martin, M. A.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2021-03-17</dc:date>
<dc:identifier>doi:10.1101/2021.03.17.435265</dc:identifier>
<dc:title><![CDATA[Antibody elicited by HIV-1 immunogen vaccination in macaques displaces Env fusion peptide and destroys a neutralizing epitope]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-03-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.01.438108v1?rss=1">
<title>
<![CDATA[
Acetylated α-tubulin residue K394 regulates microtubule stability to shape the growth of axon terminals 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.01.438108v1?rss=1</link>
<description><![CDATA[
Microtubules are essential to neuron shape and function. Therefore, the stability of the microtubule cytoskeleton must be carefully regulated. Acetylation of tubulin has the potential to directly tune microtubule stability, and proteomic studies have identified several acetylation sites in -tubulin. This includes the highly conserved residue lysine 394 (K394), which is located at the {beta}-tubulin dimer interface. Using a fly model, we show that -tubulin K394 is acetylated in the nervous system and is an essential residue. We found that an acetylation-blocking mutation in endogenous -tubulin, K394R, perturbs the synaptic morphogenesis of motoneurons by reducing microtubule stability. Intriguingly, the K394R mutation has opposite effects on the growth of two functionally and morphologically distinct motoneurons, revealing neuron-type-specific responses when microtubule stability is altered. Eliminating the deacetylase HDAC6 increases K394 acetylation, and the over-expression of HDAC6 reduces microtubule stability similar to the K394 mutant. Thus, our findings implicate -tubulin K394 and its acetylation in the regulation of microtubule stability and suggest that HDAC6 regulates K394 acetylation during synaptic morphogenesis.
]]></description>
<dc:creator>Saunders, H. A. J.</dc:creator>
<dc:creator>Johnson-Schlitz, D. M.</dc:creator>
<dc:creator>Jenkins, B. V.</dc:creator>
<dc:creator>Volkert, P. J.</dc:creator>
<dc:creator>Yang, S. Z.</dc:creator>
<dc:creator>Wildonger, J.</dc:creator>
<dc:date>2021-04-02</dc:date>
<dc:identifier>doi:10.1101/2021.04.01.438108</dc:identifier>
<dc:title><![CDATA[Acetylated α-tubulin residue K394 regulates microtubule stability to shape the growth of axon terminals]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.20.440699v1?rss=1">
<title>
<![CDATA[
Inhibition is the hallmark of CA3 intracellular dynamics around awake ripples 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.20.440699v1?rss=1</link>
<description><![CDATA[
Hippocampal ripples are transient population bursts that structure cortico-hippocampal communication and play a central role in memory processing. However, the mechanisms controlling ripple initiation in behaving animals remain poorly understood. Here we combine multisite extracellular and whole cell recordings in awake mice to contrast the brain state and ripple modulation of subthreshold dynamics across hippocampal subfields. We find that entorhinal input to DG exhibits UP and DOWN dynamics with ripples occurring exclusively in UP states. While elevated cortical input in UP states generates depolarization in DG and CA1, it produces persistent hyperpolarization in CA3 neurons. Furthermore, growing inhibition is evident in CA3 throughout the course of the ripple buildup, while DG and CA1 neurons exhibit depolarization transients 100 ms before and during ripples. These observations highlight the importance of CA3 inhibition for ripple generation, while pre-ripple responses indicate a long and orchestrated ripple initiation process in the awake state.
]]></description>
<dc:creator>Kajikawa, K.</dc:creator>
<dc:creator>Hulse, B. K.</dc:creator>
<dc:creator>Siapas, A. G.</dc:creator>
<dc:creator>Lubenov, E. V.</dc:creator>
<dc:date>2021-04-22</dc:date>
<dc:identifier>doi:10.1101/2021.04.20.440699</dc:identifier>
<dc:title><![CDATA[Inhibition is the hallmark of CA3 intracellular dynamics around awake ripples]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.23.440859v1?rss=1">
<title>
<![CDATA[
Homologous locus pairing is a transient, diffusion-mediated process in meiotic prophase 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.23.440859v1?rss=1</link>
<description><![CDATA[
The pairing of homologous chromosomes (homologs) in meiosis is essential for distributing the correct numbers of chromosomes into haploid gametes. In budding yeast, pairing depends on the formation of 150-200 Spo11-mediated double-strand breaks (DSBs) that are distributed among 16 homolog pairs, but it is not known if all, or only a subset of these DSBs, contribute to the close juxtaposition of homologs. Having established a system to measure the position of fluorescently tagged chromosomal loci in 3D space over time, we analyzed locus trajectories to determine how frequently, and how long, loci spend colocalized or apart. Continuous imaging revealed highly heterogeneous cell-to-cell behavior of foci, with the majority of cells exhibiting a "mixed" phenotype where foci move into and out of proximity, even at late stages of prophase, suggesting that the axial structures of the synaptonemal complex may be more dynamic than anticipated. The observed plateaus of the mean-squared change in distance (MSCD) between foci informed the development of a biophysical model of two diffusing polymers that captures the loss of centromere linkages as cells enter meiosis, nuclear confinement, and the formation of Spo11-dependent linkages. The predicted number of linkages per chromosome in our theoretical model closely approximates the small number (~2-4) of estimated synapsis-initiation sites, suggesting that excess DSBs have negligible effects on the overall juxtaposition of homologs. These insights into the dynamic in-terchromosomal behavior displayed during homolog pairing demonstrate the power of combining time-resolved in vivo analysis with modeling at the granular level.

Significance StatementEssential for sexual reproduction, meiosis is a specialized cell division required for the production of haploid gametes. Critical to this process is the pairing, recombination, and segregation of homologous chromosomes (homologs). While pairing and recombination are linked, it is not known how many linkages are sufficient to hold homologs in proximity. Here, we reveal that random diffusion and the placement of a small number of linkages are sufficient to establish the apparent "pairing" of homologs. We also show that colocalization between any two loci is more dynamic than anticipated. Our study is the first to provide observations of live interchromosomal dynamics during meiosis and illustrates the power of combining single-cell measurements with theoretical polymer modeling.
]]></description>
<dc:creator>Newman, T. A.</dc:creator>
<dc:creator>Beltran, B.</dc:creator>
<dc:creator>McGehee, J. M.</dc:creator>
<dc:creator>Elnatan, D.</dc:creator>
<dc:creator>Cahoon, C. K.</dc:creator>
<dc:creator>Paddy, M.</dc:creator>
<dc:creator>Chu, D. B.</dc:creator>
<dc:creator>Spakowitz, A. J.</dc:creator>
<dc:creator>Burgess, S. M.</dc:creator>
<dc:date>2021-04-24</dc:date>
<dc:identifier>doi:10.1101/2021.04.23.440859</dc:identifier>
<dc:title><![CDATA[Homologous locus pairing is a transient, diffusion-mediated process in meiotic prophase]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.26.441415v1?rss=1">
<title>
<![CDATA[
Mechanical vibration patterns elicit behavioral transitions and habituation in crawling Drosophila larvae 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.26.441415v1?rss=1</link>
<description><![CDATA[
How animals respond to repeatedly applied stimuli, and how animals respond to mechanical stimuli in particular, are important questions in behavioral neuroscience. We study adaptation to repeated mechanical agitation using the Drosophila larva. Vertical vibration stimuli elicit a discrete set of responses in crawling larvae: continuation, pause, turn, and reversal. Through high-throughput larva tracking, we characterize how the likelihood of each response depends on vibration intensity and on the timing of repeated vibration pulses. By examining transitions between behavioral states at the population and individual levels, we investigate how the animals habituate to the stimulus patterns. We identify time constants associated with desensitization to prolonged vibration, with re-sensitization during removal of a stimulus, and additional layers of habituation that operate in the overall response. Known memory-deficient mutants exhibit distinct behavior profiles and habituation time constants. An analogous simple electrical circuit suggests possible neural and molecular processes behind adaptive behavior.
]]></description>
<dc:creator>Berne, A.</dc:creator>
<dc:creator>Zhang, T.</dc:creator>
<dc:creator>Shomar, J.</dc:creator>
<dc:creator>Ferrer, A. J.</dc:creator>
<dc:creator>Valdes, A.</dc:creator>
<dc:creator>Ohyama, T.</dc:creator>
<dc:creator>Klein, M.</dc:creator>
<dc:date>2021-04-27</dc:date>
<dc:identifier>doi:10.1101/2021.04.26.441415</dc:identifier>
<dc:title><![CDATA[Mechanical vibration patterns elicit behavioral transitions and habituation in crawling Drosophila larvae]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.26.441522v1?rss=1">
<title>
<![CDATA[
Mapping and modeling the genomic basis of differential RNA isoform expression at single-cell resolution with LR-Split-seq 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.26.441522v1?rss=1</link>
<description><![CDATA[
Alternative RNA isoforms are defined by promoter choice, alternative splicing, and polyA site selection. Although differential isoform expression is known to play a large regulatory role in eukaryotes, it has proved challenging to study with standard short-read RNA-seq because of the uncertainties it leaves about the full-length structure and precise termini of transcripts. The rise in throughput and quality of long-read sequencing now makes it possible, in principle, to unambiguously identify most transcript isoforms from beginning to end. However, its application to single-cell RNA-seq has been limited by throughput and expense. Here, we develop and characterize long-read Split-seq (LR-Split-seq), which uses a combinatorial barcoding-based method for sequencing single cells and nuclei with long reads. We show that LR-Split-seq can associate isoforms with cell types with relative economy and design flexibility. We characterize LR-Split-seq for whole cells and nuclei by using the well-studied mouse C2C12 system in which mononucleated myoblast cells differentiate and fuse into multinucleated myotubes. We show that the overall results are reproducible when comparing long- and short-read data from the same cell or nucleus. We find substantial evidence of differential isoform expression during differentiation including alternative transcription start site (TSS) usage. We integrate the resulting isoform expression dynamics with snATAC-seq chromatin accessibility to validate TSS-driven isoform choices. LR-Split-seq provides an affordable method for identifying cluster-specific isoforms in single cells that can be further quantified with companion deep short-read scRNA-seq from the same cell populations.
]]></description>
<dc:creator>Rebboah, E.</dc:creator>
<dc:creator>Reese, F.</dc:creator>
<dc:creator>Williams, K.</dc:creator>
<dc:creator>Balderrama-Gutierrez, G.</dc:creator>
<dc:creator>McGill, C.</dc:creator>
<dc:creator>Trout, D.</dc:creator>
<dc:creator>Rodriguez, I. M.</dc:creator>
<dc:creator>Liang, H.</dc:creator>
<dc:creator>Wold, B. J.</dc:creator>
<dc:creator>Mortazavi, A.</dc:creator>
<dc:date>2021-04-27</dc:date>
<dc:identifier>doi:10.1101/2021.04.26.441522</dc:identifier>
<dc:title><![CDATA[Mapping and modeling the genomic basis of differential RNA isoform expression at single-cell resolution with LR-Split-seq]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.27.441657v1?rss=1">
<title>
<![CDATA[
Vivarium: an interface and engine for integrative multiscale modeling in computational biology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.27.441657v1?rss=1</link>
<description><![CDATA[
AO_SCPLOWBSTRACTC_SCPLOWO_ST_ABSMotivationC_ST_ABSThis paper introduces Vivarium - software born of the idea that it should be as easy as possible for computational biologists to define any imaginable mechanistic model, combine it with existing models, and execute them together as an integrated multiscale model. Integrative multiscale modeling confronts the complexity of biology by combining heterogeneous datasets and diverse modeling strategies into unified representations. These integrated models are then run to simulate how the hypothesized mechanisms operate as a whole. But building such models has been a labor-intensive process that requires many contributors, and they are still primarily developed on a case-by-case basis with each project starting anew. New software tools that streamline the integrative modeling effort and facilitate collaboration are therefore essential for future computational biologists.

ResultsVivarium is a Pythonic software for building integrative multiscale models. It provides an interface that makes individual models into modules that can be wired together in large composite models, parallelized across multiple CPUs, and run with Vivariums simulation engine. Vivariums utility is demonstrated by building composite models that combine several modeling frameworks: agent based models, ordinary differential equations, stochastic reaction systems, constraint-based models, solid-body physics, and spatial diffusion. This demonstrates just the beginning of what is possible - future efforts can integrate many more types of models and at many more biological scales.

AvailabilityThe models, simulation pipelines, and notebooks developed for this paper are available at the vivarium-notebooks repository: https://github.com/vivarium-collective/vivarium-notebooks. Vivarium-core is available at https://github.com/vivarium-collective/vivarium-core, and has been released on PyPI. The Vivarium Collective (https://vivarium-collective.github.io) is a repository of freely-available Vivarium processes and composites, including the processes used in Section 3. Supplementary materials provide with an extensive methodology section, with several code listings that demonstrate the basic interfaces.
]]></description>
<dc:creator>Agmon, E.</dc:creator>
<dc:creator>Spangler, R. K.</dc:creator>
<dc:creator>Skalnik, C. J.</dc:creator>
<dc:creator>Poole, W.</dc:creator>
<dc:creator>Peirce, S. M.</dc:creator>
<dc:creator>Morrison, J. H.</dc:creator>
<dc:creator>Covert, M. W.</dc:creator>
<dc:date>2021-04-28</dc:date>
<dc:identifier>doi:10.1101/2021.04.27.441657</dc:identifier>
<dc:title><![CDATA[Vivarium: an interface and engine for integrative multiscale modeling in computational biology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.30.440836v1?rss=1">
<title>
<![CDATA[
A Method for Cost-Effective and Rapid Characterization of Genetic Parts 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.30.440836v1?rss=1</link>
<description><![CDATA[
Characterizing and cataloging genetic parts are critical to the design of useful genetic circuits. Having well-characterized parts allows for the fine-tuning of genetic circuits, such that their function results in predictable outcomes. With the growth of synthetic biology as a field, there has been an explosion of genetic circuits that have been implemented in microbes to execute functions pertaining to sensing, metabolic alteration, and cellular computing. Here, we show a cost-effective and rapid method for characterizing genetic parts. Our method utilizes cell-free lysate, prepared in-house, as a medium to evaluate parts via the expression of a reporter protein. Template DNA is prepared by PCR-amplification using inexpensive primers to add variant parts to the reporter gene, and the template is added to the reaction as linear DNA without cloning. Parts that can be added in this way include promoters, operators, ribosome binding sites, insulators, and terminators. This approach, combined with the incorporation of an acoustic liquid handler and 384-well plates, allows the user to carry out high-throughput evaluations of genetic parts in a single day. By comparison, cell-based screening approaches require time-consuming cloning and have longer testing times due to overnight culture and culture density normalization steps. Further, working in cell-free lysate allows the user to exact tighter control over the expression conditions through the addition of exogenous components, or by titrating DNA concentrations rather than relying on limited plasmid copy numbers. Because this method retains a cell-like environment, the function of the genetic part will typically mimic its function in whole cells.

SUMMARYWell-characterized genetic parts are necessary for the design of novel genetic circuits. Here we describe a cost-effective, high-throughput method for rapidly characterizing genetic parts. Our method reduces cost and time by combining cell-free lysates, linear DNA to avoid cloning, and acoustic liquid handling to increase throughput and reduce reaction volumes.
]]></description>
<dc:creator>McManus, J. B.</dc:creator>
<dc:creator>Bernhards, C. B.</dc:creator>
<dc:creator>Sharpes, C. E.</dc:creator>
<dc:creator>Garcia, D. C.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:creator>Cole, S. D.</dc:creator>
<dc:creator>Emanuel, P. A.</dc:creator>
<dc:creator>Lux, M. W.</dc:creator>
<dc:date>2021-05-01</dc:date>
<dc:identifier>doi:10.1101/2021.04.30.440836</dc:identifier>
<dc:title><![CDATA[A Method for Cost-Effective and Rapid Characterization of Genetic Parts]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.04.30.442165v1?rss=1">
<title>
<![CDATA[
A somatic piRNA pathway regulates epithelial-to-mesenchymal transition of chick neural crest cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.04.30.442165v1?rss=1</link>
<description><![CDATA[
In the metazoan germline, Piwi proteins play an essential regulatory role in maintenance of stemness and self-renewal by piRNA-mediated repression of transposable elements. To date, the activity of Piwi proteins and the piRNA pathway in vertebrates was believed to be confined to the gonads. Our results reveal expression of Piwil1 in a vertebrate somatic cell type, the neural crest-a migratory embryonic stem cell population. We show that Piwil1 is expressed at low levels throughout chick neural crest development, peaking just before neural crest cells undergo an epithelial-to-mesenchymal transition to leave the neural tube and migrate into the periphery. Importantly, loss of Piwil1 impedes neural crest emigration. Small RNA sequencing reveals somatic piRNAs with sequence signatures of an active ping pong loop. Coupled with Piwil1 knockout RNA-seq, our data suggest that Piwil1 regulates expression of the transposon derived gene ERNI in the chick dorsal neural tube, which in turn suppresses Sox2 expression to precisely control the timing of neural crest specification and emigration. Our work provides mechanistic insight into a novel function of the piRNA pathway as a regulator of somatic development in vertebrates.
]]></description>
<dc:creator>Galton, R.</dc:creator>
<dc:creator>Fejes-Toth, K.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:date>2021-04-30</dc:date>
<dc:identifier>doi:10.1101/2021.04.30.442165</dc:identifier>
<dc:title><![CDATA[A somatic piRNA pathway regulates epithelial-to-mesenchymal transition of chick neural crest cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.05.24.445445v1?rss=1">
<title>
<![CDATA[
Dissection of multiple sclerosis genetics identifies B and CD4 T cells as driver cell subsets 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.05.24.445445v1?rss=1</link>
<description><![CDATA[
Multiple sclerosis (MS) is an autoimmune condition of the central nervous system with a well-characterized genetic background. Prior analyses of MS genetics have identified broad enrichments across peripheral immune cells, yet the driver immune subsets are unclear. We utilized chromatin accessibility data across hematopoietic cells to identify cell type-specific enrichments of MS genetic signals. We found that CD4 T and B cells were independently enriched for MS genetics and further refined the driver subsets to Th17 and memory B cells, respectively. We replicated our findings in data from untreated and treated MS patients and found that immunomodulatory treatments suppress chromatin accessibility at driver cell types. Integration of statistical fine-mapping and chromatin interactions nominated numerous putative causal genes, illustrating complex interplay between shared and cell-specific genes. Our study highlights how careful integration of genetics and epigenetics can provide fine-scale insights into causal cell types and nominate new genes and pathways for disease.
]]></description>
<dc:creator>Guo, M.</dc:creator>
<dc:creator>Sama, P.</dc:creator>
<dc:creator>LaBarre, B.</dc:creator>
<dc:creator>Lokhande, H.</dc:creator>
<dc:creator>Balibalos, J.</dc:creator>
<dc:creator>Chu, C.</dc:creator>
<dc:creator>Du, X.</dc:creator>
<dc:creator>Kheradpour, P.</dc:creator>
<dc:creator>Kim, C.</dc:creator>
<dc:creator>Oniskey, T.</dc:creator>
<dc:creator>Snyder, T.</dc:creator>
<dc:creator>Soghoian, D.</dc:creator>
<dc:creator>Weiner, H.</dc:creator>
<dc:creator>Chitnis, T.</dc:creator>
<dc:creator>Patsopoulos, N.</dc:creator>
<dc:date>2021-05-25</dc:date>
<dc:identifier>doi:10.1101/2021.05.24.445445</dc:identifier>
<dc:title><![CDATA[Dissection of multiple sclerosis genetics identifies B and CD4 T cells as driver cell subsets]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.06.14.448200v1?rss=1">
<title>
<![CDATA[
Timing of meristem initiation and maintenance determines the morphology of fern gametophytes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.06.14.448200v1?rss=1</link>
<description><![CDATA[
The alternation of generations in land plants occurs between the sporophyte phase and the gametophyte phase. The sporophytes of seed plants develop self-maintained, multicellular meristems, and these meristems determine plant architecture. The gametophytes of seed plants lack meristems and are heterotrophic. In contrast, the gametophytes of seed-free vascular plants, including ferns, are autotrophic and free-living, developing meristems to sustain their independent growth and proliferation. Compared to meristems in the sporophytes of seed plants, the cellular mechanisms underlying meristem development in fern gametophytes remain largely unknown. Here, using confocal time-lapse live imaging and computational segmentation and quantification, we determined different patterns of cell divisions associated with the initiation and proliferation of two distinct types of meristems in fern gametophytes. Our results reveal how the simple timing of a switch between two meristems has considerable consequences for the divergent gametophyte morphologies of two closely related ferns from Pteridaceae (Pteris and Ceratopteris). Our result provides evolutionary insight into the function and regulation of gametophyte meristems in seed-free vascular plants.

HighlightLive-imaging of cell growth and division in apical initials and lateral meristems reveals that the timing of a switch between the two meristem identities drives morphology variation in fern gametophytes.
]]></description>
<dc:creator>Wu, X.</dc:creator>
<dc:creator>Yan, A.</dc:creator>
<dc:creator>McAdam, S.</dc:creator>
<dc:creator>Banks, J. A.</dc:creator>
<dc:creator>Zhang, S.</dc:creator>
<dc:creator>Zhou, Y.</dc:creator>
<dc:date>2021-06-14</dc:date>
<dc:identifier>doi:10.1101/2021.06.14.448200</dc:identifier>
<dc:title><![CDATA[Timing of meristem initiation and maintenance determines the morphology of fern gametophytes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-06-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.01.450793v1?rss=1">
<title>
<![CDATA[
Atypical gaze patterns in autism are heterogeneous across subjects but reliable within individuals 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.01.450793v1?rss=1</link>
<description><![CDATA[
People with autism spectrum disorder (ASD) have atypical gaze onto both static visual images 1,2 and dynamic videos 3,4 that could be leveraged for diagnostic purposes 5,6. Eye tracking is important for characterizing ASD across the lifespan 7 and nowadays feasible at home (e.g., from smartphones 8). Yet gaze-based classification has been difficult to achieve, due to sources of variance both across and within subjects. Here we test three competing hypotheses: (a) that ASD could be successfully classified from the fact that gaze patterns are less reliable or noisier than in controls, (b) that gaze patterns are atypical and heterogeneous across ASD subjects but reliable over time within a subject, or (c) that gaze patterns are individually reliable and also homogenous among individuals with ASD. Leveraging dense eye tracking data from two different full-length television sitcom episodes in a total of over 150 subjects (N = 53 ASD, 107 controls) collected at two different sites, we demonstrate support for the second of these hypotheses. The findings pave the way for the investigation of autism subtypes, and for elucidating the specific visual features that best discriminate gaze patterns -- directions that will also inform neuroimaging and genetic studies of this complex disorder.
]]></description>
<dc:creator>Keles, U.</dc:creator>
<dc:creator>Kliemann, D.</dc:creator>
<dc:creator>Byrge, L.</dc:creator>
<dc:creator>Saarimaki, H.</dc:creator>
<dc:creator>Paul, L. K.</dc:creator>
<dc:creator>Kennedy, D. P.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:date>2021-07-02</dc:date>
<dc:identifier>doi:10.1101/2021.07.01.450793</dc:identifier>
<dc:title><![CDATA[Atypical gaze patterns in autism are heterogeneous across subjects but reliable within individuals]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.03.451005v1?rss=1">
<title>
<![CDATA[
Gene drive that results in addiction to a temperature sensitive version of an essential gene triggers population collapse in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.03.451005v1?rss=1</link>
<description><![CDATA[
One strategy for population suppression seeks to use gene drive to spread genes that confer conditional lethality or sterility, providing a way of combining population modification with suppression. Stimuli of potential interest could be introduced by humans, such as an otherwise benign virus or chemical, or occur naturally on a seasonal basis, such as a change in temperature. Cleave and Rescue (ClvR) selfish genetic elements use Cas9 and gRNAs to disrupt endogenous versions of an essential gene, while also including a Rescue version of the essential gene resistant to disruption. ClvR spreads by creating loss-of-function alleles of the essential gene that select against those lacking it, resulting in populations in which the Rescue provides the only source of essential gene function. In consequence, if function of the Rescue, a kind of Trojan horse now omnipresent in a population, is condition-dependent, so too will be the survival of that population. To test this idea we created a ClvR in Drosophila in which Rescue activity of an essential gene, dribble, requires splicing of a temperature-sensitive intein (TS-ClvRdbe). This element spreads to transgene fixation at 23{degrees}C, but when populations now dependent on Ts-ClvRdbe are shifted to 29{degrees}C death and sterility result in a rapid population crash. These results show that conditional population elimination can be achieved. A similar logic, in which Rescue activity is conditional, could also be used in HEG-based drive, and to bring about suppression and/or killing of specific individuals in response to other stimuli..

SIGNIFICANCE STATEMENTGene drive can be used to spread traits of interest through wild populations. In some contexts the goal is to suppress or eliminate the population. In principle, one way to achieve this goal is if the trait being spread confers on carriers conditional lethality in response to an environmental stimulus that is either introduced by humans into the target area at a specific time (a virus, otherwise benign chemical; a kind of species-specific insecticide), or that occurs naturally on a seasonal basis, such as a change in temperature. Here we show that ClvR selfish elements can be used to spread a gene that confers lethality and sterility in response to increased temperature, demonstrating that conditional population elimination can be achieved.
]]></description>
<dc:creator>Oberhofer, G.</dc:creator>
<dc:creator>Hay, B.</dc:creator>
<dc:creator>Ivy, T.</dc:creator>
<dc:date>2021-07-04</dc:date>
<dc:identifier>doi:10.1101/2021.07.03.451005</dc:identifier>
<dc:title><![CDATA[Gene drive that results in addiction to a temperature sensitive version of an essential gene triggers population collapse in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.04.451059v1?rss=1">
<title>
<![CDATA[
Mice and primates use distinct strategies for visual segmentation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.04.451059v1?rss=1</link>
<description><![CDATA[
The rodent visual system has attracted great interest in recent years due to its experimental tractability, but the fundamental mechanisms used by the mouse to represent the visual world remain unclear. In the primate, researchers have argued from both behavioral and neural evidence that a key step in visual representation is "figure-ground segmentation," the delineation of figures as distinct from backgrounds [1-4]. To determine if mice also show behavioral and neural signatures of figure-ground segmentation, we trained mice on a figure-ground segmentation task where figures were defined by gratings and naturalistic textures moving counterphase to the background. Unlike primates, mice were severely limited in their ability to segment figure from ground using the opponent motion cue, with segmentation behavior strongly dependent on the specific carrier pattern. Remarkably, when mice were forced to localize naturalistic patterns defined by opponent motion, they adopted a strategy of brute force memorization of texture patterns. In contrast, primates, including humans, macaques, and mouse lemurs, could readily segment figures independent of carrier pattern using the opponent motion cue. Consistent with mouse behavior, neural responses to the same stimuli recorded in mouse visual areas V1, RL, and LM also did not support texture-invariant segmentation of figures using opponent motion. Modeling revealed that the texture dependence of both the mouses behavior and neural responses could be explained by a feedforward neural network lacking explicit segmentation capabilities. These findings reveal a fundamental limitation in the ability of mice to segment visual objects compared to primates.
]]></description>
<dc:creator>Luongo, F. J.</dc:creator>
<dc:creator>Liu, L.</dc:creator>
<dc:creator>Ho, C. L. A.</dc:creator>
<dc:creator>Hesse, J. K.</dc:creator>
<dc:creator>Wekselblatt, J. B.</dc:creator>
<dc:creator>Lanfranchi, F.</dc:creator>
<dc:creator>Huber, D. K.</dc:creator>
<dc:creator>Tsao, D. Y.</dc:creator>
<dc:date>2021-07-05</dc:date>
<dc:identifier>doi:10.1101/2021.07.04.451059</dc:identifier>
<dc:title><![CDATA[Mice and primates use distinct strategies for visual segmentation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.20.453126v1?rss=1">
<title>
<![CDATA[
Differences in the dynamics of the tandem-SH2 modules of the Syk and ZAP-70 tyrosine kinases 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.20.453126v1?rss=1</link>
<description><![CDATA[
The catalytic activity of Syk-family tyrosine kinases is regulated by a tandem-SH2 module (tSH2 module). In the autoinhibited state, this module adopts a conformation which stabilizes an inactive conformation of the kinase domain. The binding of the tSH2 module to doubly-phosphorylated tyrosine-containing motifs necessitates a conformational change, thereby relieving kinase inhibition and promoting activation. We determined the crystal structure of the isolated tSH2 module of Syk and find, in contrast to ZAP-70, that its conformation more closely resembles that of the peptide-bound state, rather than the autoinhibited state. Hydrogen-deuterium exchange by mass spectrometry, as well as molecular dynamics simulations, reveal that the dynamics of the tSH2 modules of Syk and ZAP-70 differ, with most of these differences occurring in the C-terminal SH2 domain. Our data suggest that the conformational landscapes of the tSH2 modules in Syk and ZAP-70 have been tuned differently, such that the auto-inhibited conformation of the Syk tSH2 module is less stable. This feature of Syk likely contributes to its ability to more readily escape autoinhibition when compared to ZAP-70, consistent with tighter control of downstream signaling pathways in T cells.
]]></description>
<dc:creator>Hobbs, H. T.</dc:creator>
<dc:creator>Shah, N. H.</dc:creator>
<dc:creator>Badroos, J. M.</dc:creator>
<dc:creator>Gee, C. L.</dc:creator>
<dc:creator>Marqusee, S.</dc:creator>
<dc:creator>Kuriyan, J.</dc:creator>
<dc:date>2021-07-20</dc:date>
<dc:identifier>doi:10.1101/2021.07.20.453126</dc:identifier>
<dc:title><![CDATA[Differences in the dynamics of the tandem-SH2 modules of the Syk and ZAP-70 tyrosine kinases]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.07.23.453469v1?rss=1">
<title>
<![CDATA[
The human neuronal receptor NgR1 bridges reovirus capsid proteins to initiate infection 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.07.23.453469v1?rss=1</link>
<description><![CDATA[
Human Nogo-66 receptor 1 (NgR1) is a receptor for mammalian orthoreoviruses (reoviruses), but the mechanism of virus-receptor engagement is unknown. NgR1 binds a variety of structurally dissimilar ligands in the adult central nervous system (CNS) to inhibit axon outgrowth. Disruption of ligand binding to NgR1 and subsequent signaling can improve neuron regrowth, making NgR1 an important therapeutic target for diverse conditions such as spinal crush injuries and Alzheimer disease. To elucidate how NgR1 mediates cell binding and entry of reovirus, we defined the affinity of interaction between virus and receptor, determined the structure of the virus-receptor complex, and identified residues in the receptor required for virus binding and infection. These studies revealed that NgR1 sequences in a central concave region of the molecule establish a bridge between two copies of the viral capsid protein, {sigma}3. This unusual binding interface produces high-avidity interactions between virus and receptor and likely primes early entry steps. NgR1 sequences engaged by reovirus also are required for NgR1 binding to ligands expressed by neurons and oligodendrocytes. These studies redefine models of reovirus cell-attachment and highlight the evolution of viruses to engage multiple receptors using distinct capsid components.
]]></description>
<dc:creator>Sutherland, D. M.</dc:creator>
<dc:creator>Strebl, M.</dc:creator>
<dc:creator>Koehler, M.</dc:creator>
<dc:creator>Welsh, O. L.</dc:creator>
<dc:creator>Yu, X.</dc:creator>
<dc:creator>Hu, L.</dc:creator>
<dc:creator>dos Santos Natividade, R.</dc:creator>
<dc:creator>Knowlton, J. J.</dc:creator>
<dc:creator>Taylor, G. M.</dc:creator>
<dc:creator>Moreno, R.</dc:creator>
<dc:creator>Woerz, P.</dc:creator>
<dc:creator>Lonergan, Z. L.</dc:creator>
<dc:creator>Aravamudhan, P.</dc:creator>
<dc:creator>Guzman-Cardozo, C.</dc:creator>
<dc:creator>Alsteens, D.</dc:creator>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>Prasad, B.</dc:creator>
<dc:creator>Stehle, T.</dc:creator>
<dc:creator>Dermody, T. S.</dc:creator>
<dc:date>2021-07-24</dc:date>
<dc:identifier>doi:10.1101/2021.07.23.453469</dc:identifier>
<dc:title><![CDATA[The human neuronal receptor NgR1 bridges reovirus capsid proteins to initiate infection]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.17.456649v1?rss=1">
<title>
<![CDATA[
Mechanics of live cell elimination 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.17.456649v1?rss=1</link>
<description><![CDATA[
Cell layers eliminate unwanted cells through the extrusion process, which underlines healthy versus flawed tissue behaviors. Although several biochemical pathways have been identified, the underlying mechanical basis including the forces involved in cellular extrusion remain largely unexplored. Utilizing a phase-field model of a three-dimensional cell layer, we study the interplay of cell extrusion with cell-cell and cell-substrate interactions, in a monolayer. Independent tuning of cell-cell versus cell-substrate adhesion forces in the model reveals that a higher cell-substrate adhesion leads to a lower number of total extrusion events. We find extrusion events to be linked to both half-integer topological defects in the orientation field of the cells and to five-fold disclinations in cellular arrangements. We also show that increasing the relative cell-cell adhesion forces translates into a higher likelihood for an extrusion event to be associated with a five-fold disclination and a weaker correlation with +1/2 topological defects. We unify our findings by accessing mechanical stress fields: an extrusion event acts as a mechanism to relieve localized stress concentration.
]]></description>
<dc:creator>Monfared, S.</dc:creator>
<dc:creator>Ravichandran, G.</dc:creator>
<dc:creator>Andrade, J. E.</dc:creator>
<dc:creator>Doostmohammadi, A.</dc:creator>
<dc:date>2021-08-18</dc:date>
<dc:identifier>doi:10.1101/2021.08.17.456649</dc:identifier>
<dc:title><![CDATA[Mechanics of live cell elimination]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.08.19.456988v1?rss=1">
<title>
<![CDATA[
Critical Role for Isoprenoids in Apicoplast Biogenesis by Malaria Parasites 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.08.19.456988v1?rss=1</link>
<description><![CDATA[
Isopentenyl pyrophosphate (IPP) is an essential metabolic output of the apicoplast organelle in Plasmodium falciparum malaria parasites and is required for prenylation-dependent vesicular trafficking and other cellular processes. We have elucidated a critical and previously uncharacterized role for IPP in apicoplast biogenesis. Inhibiting IPP synthesis blocks apicoplast elongation and inheritance by daughter merozoites, and apicoplast biogenesis is rescued by exogenous IPP and polyprenols. Knockout of the only known isoprenoid-dependent apicoplast pathway, tRNA prenylation by MiaA, has no effect on blood-stage parasites and thus cannot explain apicoplast reliance on IPP. However, we have localized an annotated polyprenyl synthase (PPS) to the apicoplast lumen. PPS knockdown is lethal to parasites, rescued by IPP, and blocks apicoplast biogenesis, thus explaining apicoplast dependence on isoprenoid synthesis. We hypothesize that PPS synthesizes long-chain polyprenols critical for apicoplast membrane fluidity and biogenesis. This work critically expands the paradigm for isoprenoid utilization in malaria parasites and identifies a novel essential branch of apicoplast metabolism suitable for therapeutic targeting.
]]></description>
<dc:creator>Okada, M.</dc:creator>
<dc:creator>Rajaram, K.</dc:creator>
<dc:creator>Swift, R. P.</dc:creator>
<dc:creator>Mixon, A.</dc:creator>
<dc:creator>Maschek, J. A.</dc:creator>
<dc:creator>Prigge, S. T.</dc:creator>
<dc:creator>Sigala, P. A.</dc:creator>
<dc:date>2021-08-19</dc:date>
<dc:identifier>doi:10.1101/2021.08.19.456988</dc:identifier>
<dc:title><![CDATA[Critical Role for Isoprenoids in Apicoplast Biogenesis by Malaria Parasites]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-08-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.16.459846v1?rss=1">
<title>
<![CDATA[
Biomechanical interactions of Schistosoma mansoni eggs with vascular endothelial cells facilitate egg extravasation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.16.459846v1?rss=1</link>
<description><![CDATA[
The eggs of the parasitic blood fluke, Schistosoma, are the main drivers of the chronic pathologies associated with schistosomiasis, a disease of poverty afflicting approximately 220 million people worldwide. Eggs laid by Schistosoma mansoni in the bloodstream of the host are encapsulated by vascular endothelial cells (VECs), the first step in the migration of the egg from the blood stream into the lumen of the gut and eventual exit from the body. The biomechanics associated with encapsulation and extravasation of the egg are poorly understood. We demonstrate that S. mansoni eggs induce VECs to form two types of membrane extensions during encapsulation; filopodia that probe eggshell surfaces and intercellular nanotubes that presumably facilitate VEC communication. Encapsulation efficiency, the number of filopodia and intercellular nanotubes, and the length of these structures depend on the eggs vitality and, to a lesser degree, its maturation state. During encapsulation, live eggs induce VEC contractility and membranous structures formation, in a Rho/ROCK pathway-dependent manner. Using elastic hydrogels embedded with fluorescent microbeads as substrates to culture VECs, live eggs induce VECs to exert significantly greater contractile forces during encapsulation than dead eggs, which leads to 3D deformations on both the VEC monolayer and the flexible substrate underneath. These significant mechanical deformations cause the VEC monolayer tension to fluctuate with eventual rupture of VEC junctions, thus facilitating egg transit out of the blood vessel. Overall, our data on the mechanical interplay between host VECs and the schistosome egg improve our understanding of how this parasite manipulates its immediate environment to maintain disease transmission.
]]></description>
<dc:creator>Yeh, Y.-T.</dc:creator>
<dc:creator>Skinner, D. E.</dc:creator>
<dc:creator>Criado-Hidalgo, E.</dc:creator>
<dc:creator>Chen, N. S.</dc:creator>
<dc:creator>Garcia-De Herreros, A.</dc:creator>
<dc:creator>El-Sakary, N.</dc:creator>
<dc:creator>Liu, L.</dc:creator>
<dc:creator>Zhang, S.</dc:creator>
<dc:creator>Chien, S.</dc:creator>
<dc:creator>Lasheras, J. C.</dc:creator>
<dc:creator>del Alamo, J. C.</dc:creator>
<dc:creator>Caffrey, C. R.</dc:creator>
<dc:date>2021-09-17</dc:date>
<dc:identifier>doi:10.1101/2021.09.16.459846</dc:identifier>
<dc:title><![CDATA[Biomechanical interactions of Schistosoma mansoni eggs with vascular endothelial cells facilitate egg extravasation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.24.461751v1?rss=1">
<title>
<![CDATA[
Endotaxis: A Universal Algorithm for Mapping, Goal-Learning, and Navigation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.24.461751v1?rss=1</link>
<description><![CDATA[
An animal entering a new environment typically faces three challenges: explore the space for resources, memorize their locations, and navigate towards those targets as needed. Experimental work on exploration, mapping, and navigation has mostly focused on simple environments - such as an open arena [68], a pond [42], or a desert [44] - and much has been learned about neural signals in diverse brain areas under these conditions [12, 54]. However, many natural environments are highly structured, such as a system of burrows, or of intersecting paths through the underbrush. Similarly, for many cognitive tasks, a sequence of simple actions can give rise to complex solutions. Here we propose an algorithm that learns the structure of a complex environment, discovers useful targets during exploration, and navigates back to those targets by the shortest path. It makes use of a behavioral module common to all motile animals, namely the ability to follow an odor to its source [4]. We show how the brain can learn to generate internal "virtual odors" that guide the animal to any location of interest. This endotaxis algorithm can be implemented with a simple 3-layer neural circuit using only biologically realistic structures and learning rules. Several neural components of this scheme are found in brains from insects to humans. Nature may have evolved a general mechanism for search and navigation on the ancient backbone of chemotaxis.
]]></description>
<dc:creator>Zhang, T.</dc:creator>
<dc:creator>Rosenberg, M.</dc:creator>
<dc:creator>Perona, P.</dc:creator>
<dc:creator>Meister, M.</dc:creator>
<dc:date>2021-09-25</dc:date>
<dc:identifier>doi:10.1101/2021.09.24.461751</dc:identifier>
<dc:title><![CDATA[Endotaxis: A Universal Algorithm for Mapping, Goal-Learning, and Navigation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.09.26.461880v1?rss=1">
<title>
<![CDATA[
How to model DNA replication in stochastic models of synthetic genetic circuits (and why) 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.09.26.461880v1?rss=1</link>
<description><![CDATA[
Biocircuit modeling sometimes requires explicit tracking of a self-replicating DNA species. The most obvious, straightforward way to model a replicating DNA is structurally unstable and leads to pathological model behavior. We describe a simple, stable replication mechanism with good model behavior and show how to derive it from a mechanistic model of ColE1 replication.
]]></description>
<dc:creator>Clamons, S.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2021-09-27</dc:date>
<dc:identifier>doi:10.1101/2021.09.26.461880</dc:identifier>
<dc:title><![CDATA[How to model DNA replication in stochastic models of synthetic genetic circuits (and why)]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-09-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.12.464058v1?rss=1">
<title>
<![CDATA[
Control of protein activity by photoinduced spin polarized charge reorganization 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.12.464058v1?rss=1</link>
<description><![CDATA[
Considerable electric fields are present within living cells, and the role of bioelectricity has been well established at the organismal level. Yet little is known about electric-field effects on protein function. Here we use phototriggered charge injection from a site-specifically attached ruthenium photosensitizer to directly demonstrate the effects of charge redistribution within a protein. We find that binding of an antibody to phosphoglycerate kinase (PGK) is increased two folds under illumination. Remarkably, illumination is found to suppress the enzymatic activity of PGK by a factor as large as three. These responses are sensitive to the photosensitizer position on the protein. Surprisingly, left (but not right) circularly polarized light elicits these responses, indicating that the electrons involved in the observed dynamics are spin polarized, due to spin filtration by protein chiral structures. Our results directly establish the contribution of electrical polarization as an allosteric signal within proteins. Future experiments with phototriggered charge injection will allow delineation of charge rearrangement pathways within proteins and will further depict their effects on protein function.

Significance StatementThe role of well-placed charges within proteins in mediating biological functions, from protein-protein association to enzyme kinetics, is well documented. Here we go beyond this static picture and show that charge motions can exert significant effects on protein function. Injecting charge from a photosensitizer, we demonstrate a three-fold decrease in enzymatic activity and a two-fold increase of antibody-antigen binding. These effects depend on the specific position of the photosensitizer on the protein. Our results point to charge reorganization as a form of allostery that complements known allosteric mechanisms such as conformational changes and dynamics.
]]></description>
<dc:creator>Ghosh, S.</dc:creator>
<dc:creator>Ghosh, K. B.</dc:creator>
<dc:creator>Levy, D.</dc:creator>
<dc:creator>Scheerer, D.</dc:creator>
<dc:creator>Riven, I.</dc:creator>
<dc:creator>Shin, J.</dc:creator>
<dc:creator>Gray, H.</dc:creator>
<dc:creator>Naaman, R.</dc:creator>
<dc:creator>Haran, G.</dc:creator>
<dc:date>2021-10-13</dc:date>
<dc:identifier>doi:10.1101/2021.10.12.464058</dc:identifier>
<dc:title><![CDATA[Control of protein activity by photoinduced spin polarized charge reorganization]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.15.464407v1?rss=1">
<title>
<![CDATA[
Single-Shot Optical Projection tomography for high-speed volumetric imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.15.464407v1?rss=1</link>
<description><![CDATA[
We present a single-shot adaptation of Optical Projection Tomography (OPT) for high-speed volumetric snapshot imaging of dynamic mesoscopic samples. Conventional OPT has been applied to in vivo imaging of animal models such as D. rerio but the sequential acquisition of projection images required for volumetric reconstruction typically requires samples to be immobilised during the acquisition of an OPT data set. We present a proof-of-principle system capable of single-shot imaging of a 1 mm diameter volume, demonstrating camera-limited rates of up to 62.5 volumes/second, which we have applied to 3D imaging of a freely-swimming zebrafish embryo. This is achieved by recording 8 projection views simultaneously on 4 low-cost CMOS cameras. With no stage required to rotate the sample, this single-shot OPT system can be implemented with a component cost of under {pound}5,000. The system design can be adapted to different sized fields of view and may be applied to a broad range of dynamic samples, including fluid dynamics.
]]></description>
<dc:creator>Darling, C. J.</dc:creator>
<dc:creator>Davis, S. P. X.</dc:creator>
<dc:creator>Kumar, S.</dc:creator>
<dc:creator>French, P. M. W.</dc:creator>
<dc:creator>McGinty, J. A.</dc:creator>
<dc:date>2021-10-16</dc:date>
<dc:identifier>doi:10.1101/2021.10.15.464407</dc:identifier>
<dc:title><![CDATA[Single-Shot Optical Projection tomography for high-speed volumetric imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.10.22.465381v1?rss=1">
<title>
<![CDATA[
Motor processivity and speed determine structure and dynamics of microtubule-motor assemblies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.10.22.465381v1?rss=1</link>
<description><![CDATA[
1Active matter systems can generate highly ordered structures, avoiding equilibrium through the consumption of energy by individual constituents. How the microscopic parameters that characterize the active agents are translated to the observed mesoscopic properties of the assembly has remained an open question. These active systems are prevalent in living matter; for example, in cells, the cytoskeleton is organized into structures such as the mitotic spindle through the coordinated activity of many motor proteins walking along microtubules. Here, we investigate how the microscopic motor-microtubule interactions affect the coherent structures formed in a reconstituted motor-microtubule system. This question is of deeper evolutionary significance as we suspect motor and microtubule type contribute to the shape and size of resulting structures. We explore key parameters experimentally and theoretically, using a variety of motors with different speeds, proces-sivities, and directionalities. We demonstrate that aster size depends on the motor used to create the aster, and develop a model for the distribution of motors and microtubules in steady-state asters that depends on parameters related to motor speed and processivity. Further, we show that network contraction rates scale linearly with the single-motor speed in quasi one-dimensional contraction experiments. In all, this theoretical and experimental work helps elucidate how microscopic motor properties are translated to the much larger scale of collective motor-microtubule assemblies.
]]></description>
<dc:creator>Banks, R. A.</dc:creator>
<dc:creator>Galstyan, V.</dc:creator>
<dc:creator>Lee, H. J.</dc:creator>
<dc:creator>Hirokawa, S.</dc:creator>
<dc:creator>Ierokomos, A.</dc:creator>
<dc:creator>Ross, T. D.</dc:creator>
<dc:creator>Bryant, Z.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2021-10-23</dc:date>
<dc:identifier>doi:10.1101/2021.10.22.465381</dc:identifier>
<dc:title><![CDATA[Motor processivity and speed determine structure and dynamics of microtubule-motor assemblies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-10-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.11.29.470404v1?rss=1">
<title>
<![CDATA[
Hypothermia Suppresses Uncoupling of Oxidative-Phosphorylation after Neonatal Cerebral Hypoxia-Ischemia 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.11.29.470404v1?rss=1</link>
<description><![CDATA[
Hypoxia-ischemia (HI), which disrupts the oxygen supply-demand balance in the brain by impairing blood oxygen supply and the cerebral metabolic rate of oxygen (CMRO2), is a leading cause of neonatal brain injury. However, it is unclear how post-HI hypothermia helps to restore the balance, as cooling reduces CMRO2. Also, how transient HI leads to secondary energy failure (SEF) in neonatal brains remains elusive. Using photoacoustic microscopy, we examined the effects of HI on CMRO2 in awake 10-day-old mice, supplemented by bioenergetic analysis of purified cortical mitochondria. Our results show that while HI suppresses ipsilateral CMRO2, it sparks a prolonged CMRO2-surge post-HI, associated with increased mitochondrial oxygen consumption, superoxide emission, and reduced mitochondrial membrane potential necessary for ATP synthesis--indicating oxidative phosphorylation (OXPHOS) uncoupling. Post-HI hypothermia prevents the CMRO2-surge by constraining oxygen extraction fraction, reduces mitochondrial oxidative stress, and maintains ATP and N-acetylaspartate levels, resulting in attenuated infarction at 24 hours post-HI. Our findings suggest that OXPHOS-uncoupling induced by the post-HI CMRO2-surge underlies SEF and blocking the surge is a key mechanism of hypothermia protection. Also, our study highlights the potential of optical CMRO2-measurements for detecting neonatal HI brain injury and guiding the titration of therapeutic hypothermia at the bedside.
]]></description>
<dc:creator>Sun, N.</dc:creator>
<dc:creator>Sun, Y.-Y.</dc:creator>
<dc:creator>Cao, R.</dc:creator>
<dc:creator>Chen, H.-R.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Fugate, E.</dc:creator>
<dc:creator>Smucker, M. R.</dc:creator>
<dc:creator>Kuo, Y.-M.</dc:creator>
<dc:creator>Grant, P. E.</dc:creator>
<dc:creator>Lindquist, D. M.</dc:creator>
<dc:creator>Kuan, C.-Y.</dc:creator>
<dc:creator>Hu, S.</dc:creator>
<dc:date>2021-11-30</dc:date>
<dc:identifier>doi:10.1101/2021.11.29.470404</dc:identifier>
<dc:title><![CDATA[Hypothermia Suppresses Uncoupling of Oxidative-Phosphorylation after Neonatal Cerebral Hypoxia-Ischemia]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-11-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2021.12.15.472856v1?rss=1">
<title>
<![CDATA[
Precise quantification of behavioral individuality from 80 million decisions across 183,000 flies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2021.12.15.472856v1?rss=1</link>
<description><![CDATA[
Individual animals behave differently from each other. This variability is a component of personality and arises even when genetics and environment are held constant. Discovering the biological mechanisms underlying behavioral variability depends on efficiently measuring individual behavioral bias, a requirement that is facilitated by automated, high-throughput experiments. We compiled a large data set of individual locomotor behavior measures, acquired from over 183,000 fruit flies walking in Y-shaped mazes. With this data set we first conducted a "computational ethology natural history" study to quantify the distribution of individual behavioral biases with unprecedented precision and examine correlations between behavioral measures with high power. We discovered a slight, but highly significant, left-bias in spontaneous locomotor decision-making. We then used the data to evaluate standing hypotheses about biological mechanisms affecting behavioral variability, specifically: the neuromodulator serotonin and its precursor transporter, heterogametic sex, and temperature. We found a variety of significant effects associated with each of these mechanisms that were behavior-dependent. This indicates that the relationship between biological mechanisms and behavioral variability may be highly context dependent. Going forward, automation of behavioral experiments will likely be essential in teasing out the complex causality of individuality.
]]></description>
<dc:creator>de Bivort, B. L.</dc:creator>
<dc:creator>Buchanan, S. M.</dc:creator>
<dc:creator>Skutt-Kakaria, K. J.</dc:creator>
<dc:creator>Gajda, E.</dc:creator>
<dc:creator>O'Leary, C. J.</dc:creator>
<dc:creator>Reimers, P.</dc:creator>
<dc:creator>Akhund-Zade, J.</dc:creator>
<dc:creator>Senft, R.</dc:creator>
<dc:creator>Maloney, R.</dc:creator>
<dc:creator>Ho, S.</dc:creator>
<dc:creator>Werkhoven, Z.</dc:creator>
<dc:creator>Smith, M. A.-Y.</dc:creator>
<dc:date>2021-12-17</dc:date>
<dc:identifier>doi:10.1101/2021.12.15.472856</dc:identifier>
<dc:title><![CDATA[Precise quantification of behavioral individuality from 80 million decisions across 183,000 flies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-12-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.07.482710v1?rss=1">
<title>
<![CDATA[
Cell Chromatography: Biocompatible chromatographic separation and interrogation of microbial cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.07.482710v1?rss=1</link>
<description><![CDATA[
The isolation of pure, single colonies lies at the heart of experimental microbiology. However, a microbial colony typically contains around one million cells at all stages of the life cycle. Here we describe a novel, cell chromatography method that facilitates the capture, purification and interrogation of microbial cells from both single and mixed cultures. The method described relies on, but is not limited to, differences in surface charge to separate bacterial strains. The method is fully biocompatible, leading to no significant loss of cell viability. The chromatographic capture of cells, combined with selective elution methods facilitates a greater level of experimental control over the sample inputs required for downstream high throughput and high sensitivity, analytical methods. The application of the method for interrogating the antibiotic resistance of bacterial strains and for the separation of bacteria from environmental samples is illustrated.
]]></description>
<dc:creator>Hazu, M.</dc:creator>
<dc:creator>Ahmed, A.</dc:creator>
<dc:creator>Curry, E. A.</dc:creator>
<dc:creator>Hornby, D. P.</dc:creator>
<dc:creator>Gjerde, D. T.</dc:creator>
<dc:date>2022-03-07</dc:date>
<dc:identifier>doi:10.1101/2022.03.07.482710</dc:identifier>
<dc:title><![CDATA[Cell Chromatography: Biocompatible chromatographic separation and interrogation of microbial cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.03.25.485873v1?rss=1">
<title>
<![CDATA[
HIV-1 CD4-binding site germline antibody-Env structures inform vaccine design 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.03.25.485873v1?rss=1</link>
<description><![CDATA[
BG24, a VRC01-class broadly neutralizing antibody (bNAb) against HIV-1 Env with relatively few somatic hypermutations (SHMs), represents a promising target for vaccine strategies to elicit CD4-binding site (CD4bs) bNAbs. To understand how SHMs correlate with BG24 neutralization of HIV-1, we solved 4.1 [A] and 3.4 [A] single-particle cryo-EM structures of two inferred germline (iGL) BG24 precursors complexed with engineered Env-based immunogens lacking CD4bs N-glycans. Structures revealed critical Env contacts by BG24iGL and identified antibody light chain structural features that impede Env recognition. In addition, biochemical data and cryo-EM structures of BG24iGL variants bound to Envs with CD4bs glycans present provided insights into N-glycan accommodation, including structural modes of light chain adaptations in the presence of the N276gp120 glycan. Together, these findings revealed Env regions critical for germline antibody recognition and potential sites to alter in immunogen design.
]]></description>
<dc:creator>Dam, K.-M. A.</dc:creator>
<dc:creator>Barnes, C. O.</dc:creator>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>Schoofs, T.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2022-03-26</dc:date>
<dc:identifier>doi:10.1101/2022.03.25.485873</dc:identifier>
<dc:title><![CDATA[HIV-1 CD4-binding site germline antibody-Env structures inform vaccine design]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-03-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.01.486789v1?rss=1">
<title>
<![CDATA[
Functional Cell Types in the Mouse Superior Colliculus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.01.486789v1?rss=1</link>
<description><![CDATA[
The superior colliculus (SC) represents a major visual processing station in the mammalian brain that receives input from many types of retinal ganglion cells (RGCs). How many parallel channels exist in the SC, and what information does each encode? Here we recorded from mouse superficial SC neurons under a battery of visual stimuli including those used for classification of RGCs. An unsupervised clustering algorithm identified 24 functional types based on their visual responses. They fall into two groups: one that responds similarly to RGCs, and another with more diverse and specialized stimulus selectivity. The second group is dominant at greater depths, consistent with a vertical progression of signal processing in the SC. Cells of the same functional type tend to cluster near each other in anatomical space. Compared to the retina, the visual representation in the SC has lower dimensionality, consistent with a sifting process along the visual pathway.
]]></description>
<dc:creator>Li, Y.</dc:creator>
<dc:creator>Meister, M.</dc:creator>
<dc:date>2022-04-05</dc:date>
<dc:identifier>doi:10.1101/2022.04.01.486789</dc:identifier>
<dc:title><![CDATA[Functional Cell Types in the Mouse Superior Colliculus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.06.487277v1?rss=1">
<title>
<![CDATA[
Isometric Spiracular Scaling in Scarab Beetles: Implications for Diffusive and Advective Oxygen Transport 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.06.487277v1?rss=1</link>
<description><![CDATA[
The scaling of respiratory structures has been hypothesized to be a major driving factor in the evolution of many aspects of animal physiology. Here we provide the first assessment of the scaling of the spiracles in insects using ten scarab beetle species differing 180x in mass, including some of the most massive extant insect species. Using X-ray microtomography, we measured the cross-sectional area and depth of all eight spiracles, enabling the calculation of their diffusive and advective capacities. Each of these metrics scaled with geometric isometry.Because diffusive capacities scale with lower slopes than metabolic rates, the largest beetles measured require 10-fold higher PO2 gradients across the spiracles to sustain metabolism by diffusion compared to the smallest species. Large beetles can exchange sufficient oxygen for resting metabolism by diffusion across the spiracles, but not during flight. In contrast, spiracular advective capacities scale similarly or more steeply than metabolic rates, so spiracular advective capacities should match or exceed respiratory demands in the largest beetles. These data illustrate a general principle of gas exchange: scaling of respiratory transport structures with geometric isometry diminishes the potential for diffusive gas exchange but enhances advective capacities; combining such structural scaling with muscle-driven ventilation allows larger animals to achieve high metabolic rates when active.
]]></description>
<dc:creator>Wagner, J. M.</dc:creator>
<dc:creator>Klok, C. J.</dc:creator>
<dc:creator>Duell, M. E.</dc:creator>
<dc:creator>Socha, J.</dc:creator>
<dc:creator>Cao, G.</dc:creator>
<dc:creator>Gong, H.</dc:creator>
<dc:creator>Harrison, J. F.</dc:creator>
<dc:date>2022-04-08</dc:date>
<dc:identifier>doi:10.1101/2022.04.06.487277</dc:identifier>
<dc:title><![CDATA[Isometric Spiracular Scaling in Scarab Beetles: Implications for Diffusive and Advective Oxygen Transport]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.07.487541v1?rss=1">
<title>
<![CDATA[
Restricting α-Synuclein Transport into Mitochondria by Inhibition of α-Synuclein-VDAC Complexation as a Potential Therapeutic Target for Parkinson's Disease Treatment 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.07.487541v1?rss=1</link>
<description><![CDATA[
Involvement of alpha-synuclein (Syn) in Parkinsons disease (PD) is complicated and difficult to trace on cellular and molecular levels. Recently we established that Syn can regulate mitochondrial function by voltage-activated complexation with the Voltage-Dependent Anion Channel (VDAC) of the outer mitochondrial membrane. When complexed with Syn, the VDAC pore is partially blocked, reducing the transport of ATP/ADP and other metabolites. Further, Syn can translocate into the mitochondria through VDAC, where it interferes with mitochondrial respiration. Recruitment of Syn to the VDAC-containing lipid membrane appears to be a crucial prerequisite for both the blockage and translocation processes. Here we report an inhibitory effect of HK2p, a small membrane-binding peptide from the mitochondria-targeting N-terminus of hexokinase 2, on the Syn membrane binding, and hence on Syn complex formation with VDAC and translocation through it. In electrophysiology experiments, addition of HK2p at micromolar concentrations to the same side of the membrane as Syn results in dramatic reduction of the frequency of blockage events in a concentration-dependent manner, reporting on complexation inhibition. Using two complementary methods of measuring protein-membrane binding, bilayer overtone analysis and fluorescence correlation spectroscopy, we found that HK2p induces detachment of Syn from lipid membranes. Experiments with live HeLa cells using proximity ligation assay confirmed that HK2p impedes Syn entry into mitochondria. Our results demonstrate that it is possible to regulate Syn-VDAC complexation by a rationally designed peptide, thus suggesting new avenues in the search for peptide therapeutics to alleviate Syn mitochondrial toxicity in PD and other synucleinopathies.
]]></description>
<dc:creator>Rajendran, M.</dc:creator>
<dc:creator>Queralt-Martin, M.</dc:creator>
<dc:creator>Gurnev, P. A.</dc:creator>
<dc:creator>Rosencrans, W. M.</dc:creator>
<dc:creator>Rovini, A.</dc:creator>
<dc:creator>Jacobs, D.</dc:creator>
<dc:creator>Abrantes, K.</dc:creator>
<dc:creator>Hoogerheide, D. P.</dc:creator>
<dc:creator>Bezrukov, S. M.</dc:creator>
<dc:creator>Rostovtseva, T. K.</dc:creator>
<dc:date>2022-04-08</dc:date>
<dc:identifier>doi:10.1101/2022.04.07.487541</dc:identifier>
<dc:title><![CDATA[Restricting α-Synuclein Transport into Mitochondria by Inhibition of α-Synuclein-VDAC Complexation as a Potential Therapeutic Target for Parkinson's Disease Treatment]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.14.488259v1?rss=1">
<title>
<![CDATA[
BANKSY: A Spatial Omics Algorithm that Unifies Cell Type Clustering and Tissue Domain Segmentation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.14.488259v1?rss=1</link>
<description><![CDATA[
Each cell type in a solid tissue has a characteristic transcriptome and spatial arrangement, both of which are observable using modern spatial omics assays. However, the common practice is still to ignore spatial information when clustering cells to identify cell types. In fact, spatial location is typically considered only when solving the related, but distinct, problem of demarcating tissue domains (which could include multiple cell types). We present BANKSY, an algorithm that unifies cell type clustering and domain segmentation by constructing a product space of cell and neighbourhood transcriptomes, representing cell state and microenvironment, respectively. BANKSYs spatial kernel-based feature augmentation strategy improves per-formance and scalability on both tasks when tested on FISH-based and sequencing-based spatial omics data. Uniquely, BANKSY identified hitherto undetected niche-dependent cell states in two mouse brain regions. Lastly, we show that quality control of spatial omics data can be formulated as a domain identification problem and solved using BANKSY. BANKSY represents a biologically motivated, scalable, and versatile framework for analyzing spatial omics data.
]]></description>
<dc:creator>Singhal, V.</dc:creator>
<dc:creator>Chou, N.</dc:creator>
<dc:creator>Lee, J.</dc:creator>
<dc:creator>Liu, J.</dc:creator>
<dc:creator>Chock, W. K.</dc:creator>
<dc:creator>Lin, L.</dc:creator>
<dc:creator>Chang, Y.-C.</dc:creator>
<dc:creator>Teo, E.</dc:creator>
<dc:creator>Lee, H. K.</dc:creator>
<dc:creator>Chen, K. H.</dc:creator>
<dc:creator>Prabhakar, S.</dc:creator>
<dc:date>2022-04-15</dc:date>
<dc:identifier>doi:10.1101/2022.04.14.488259</dc:identifier>
<dc:title><![CDATA[BANKSY: A Spatial Omics Algorithm that Unifies Cell Type Clustering and Tissue Domain Segmentation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.22.489157v1?rss=1">
<title>
<![CDATA[
Honey bee functional genomics using symbiont-mediated RNAi 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.22.489157v1?rss=1</link>
<description><![CDATA[
Bees are indispensable pollinators and model organisms for studying social behavior, development, and cognition. However, their eusociality makes it difficult to use standard forward genetic approaches to study gene function. To fill this gap, we engineered the bee gut bacterium Snodgrassella alvi to induce a host RNA interference response that reduces expression of a targeted gene. To employ this FUGUES (FUnctional Genomics Using Engineered Symbionts) procedure, a double-stranded RNA expression plasmid is cloned in Escherichia coli using Golden Gate assembly and then transferred to S. alvi. Adult worker bees are then colonized with engineered S. alvi. Finally, gene knockdown is verified through qRT-PCR, and bee phenotypes of interest can be further assessed. Expression of targeted genes is reduced by as much as 50-75% throughout the entire bee body by five days after colonization. This protocol can be accomplished in four weeks by bee researchers with microbiology and molecular cloning skills.
]]></description>
<dc:creator>Lariviere, P. J.</dc:creator>
<dc:creator>Leonard, S. P.</dc:creator>
<dc:creator>Horak, R. D.</dc:creator>
<dc:creator>Powell, J. E.</dc:creator>
<dc:creator>Barrick, J. E.</dc:creator>
<dc:date>2022-04-25</dc:date>
<dc:identifier>doi:10.1101/2022.04.22.489157</dc:identifier>
<dc:title><![CDATA[Honey bee functional genomics using symbiont-mediated RNAi]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.04.28.489561v1?rss=1">
<title>
<![CDATA[
ST6GAL1 sialyltransferase promotes acinar to ductal metaplasia and pancreatic cancer progression 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.04.28.489561v1?rss=1</link>
<description><![CDATA[
The role of aberrant glycosylation in pancreatic ductal adenocarcinoma (PDAC) remains an under-investigated area of research. In this study, we determined that the ST6GAL1 sialyltransferase, which adds 2,6-linked sialic acids to N-glycosylated proteins, is upregulated in patients with early-stage PDAC, and further increased in advanced disease. A tumor-promoting function for ST6GAL1 was elucidated using tumor xenograft models with human PDAC cells. Additionally, we developed a genetically-engineered mouse (GEM) with transgenic expression of ST6GAL1 in the pancreas, and found that mice with dual expression of ST6GAL1 and oncogenic KRASG12D have greatly accelerated PDAC progression and mortality compared with mice expressing KRASG12D alone. As ST6GAL1 imparts progenitor-like characteristics, we interrogated ST6GAL1s role in acinar to ductal metaplasia (ADM), a process that fosters neoplasia by reprogramming acinar cells into ductal, progenitor-like cells. We confirmed that ST6GAL1 promotes ADM using multiple models including the 266-6 cell line, GEM-derived organoids and tissues, and an in vivo model of inflammation-induced ADM. EGFR is a key driver of ADM and is known to be activated by ST6GAL1-mediated sialylation. Importantly, EGFR activation was dramatically increased in acinar cells and organoids from mice with transgenic ST6GAL1 expression. These collective results highlight a novel glycosylation-dependent mechanism involved in early stages of pancreatic neoplasia.
]]></description>
<dc:creator>Chakraborty, A.</dc:creator>
<dc:creator>Bhalerao, N.</dc:creator>
<dc:creator>Marciel, M. P.</dc:creator>
<dc:creator>Hwang, J.</dc:creator>
<dc:creator>Britain, C.</dc:creator>
<dc:creator>Eltoum, E. E.</dc:creator>
<dc:creator>Jones, R. B.</dc:creator>
<dc:creator>Alexander, K. L.</dc:creator>
<dc:creator>Smythies, L. E.</dc:creator>
<dc:creator>Smith, P. D.</dc:creator>
<dc:creator>Crossman, D. K.</dc:creator>
<dc:creator>Crowley, M. R.</dc:creator>
<dc:creator>Shin, B.</dc:creator>
<dc:creator>Harrington, L. E.</dc:creator>
<dc:creator>Yan, Z.</dc:creator>
<dc:creator>Bethea, M. M.</dc:creator>
<dc:creator>Hunter, C. S.</dc:creator>
<dc:creator>Klug, C. A.</dc:creator>
<dc:creator>Buchsbaum, D. J.</dc:creator>
<dc:creator>Bellis, S. L.</dc:creator>
<dc:date>2022-04-28</dc:date>
<dc:identifier>doi:10.1101/2022.04.28.489561</dc:identifier>
<dc:title><![CDATA[ST6GAL1 sialyltransferase promotes acinar to ductal metaplasia and pancreatic cancer progression]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.08.495399v1?rss=1">
<title>
<![CDATA[
Emergent Actin Flows Explain Diverse Parasite Gliding Modes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.08.495399v1?rss=1</link>
<description><![CDATA[
During host infection, single-celled apicomplexan parasites like Plasmodium and Toxoplasma use a motility mechanism called gliding, which differs fundamentally from other known mechanisms of eukaryotic cell motility. Gliding is thought to be powered by a thin layer of flowing filamentous (F)-actin1- 3 sandwiched between the plasma membrane and a myosin-coated4,5 inner membrane complex. How this surface actin layer drives the diverse apicomplexan gliding modes observed experimentally - helical, circular, and twirling6,7, and patch8, pendulum9, or rolling2 - presents a rich biophysical puzzle. Here, we use single-molecule imaging to track individual actin filaments and myosin complexes in live Toxoplasma gondii. Based on these data, we hypothesize that F-actin flows arise by self-organization, rather than following a microtubule-based template as previously believed. We develop a continuum model of emergent F-actin flow within the unusual confines provided by parasite geometry. In the presence of F-actin turnover, our model predicts the emergence of a steady-state mode in which actin transport is largely rearward. Removing actin turnover leads to actin patches that recirculate up and down the cell, a "cyclosis" that we observe experimentally for drug-stabilized actin bundles in live parasites. These findings provide a mechanism by which actin turnover governs a transition between distinct self-organized F-actin states, whose properties can account for the diverse gliding modes known to occur. More broadly, we illustrate how different forms of gliding motility can emerge as an intrinsic consequence of the self-organizing properties of F-actin flow in a confined geometry.
]]></description>
<dc:creator>Hueschen, C. L.</dc:creator>
<dc:creator>Segev Zarko, L.-a.</dc:creator>
<dc:creator>Chen, J.-H.</dc:creator>
<dc:creator>LeGros, M. A.</dc:creator>
<dc:creator>Larabell, C. A.</dc:creator>
<dc:creator>Boothroyd, J. C.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:creator>Dunn, A. R.</dc:creator>
<dc:date>2022-06-09</dc:date>
<dc:identifier>doi:10.1101/2022.06.08.495399</dc:identifier>
<dc:title><![CDATA[Emergent Actin Flows Explain Diverse Parasite Gliding Modes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.09.495547v1?rss=1">
<title>
<![CDATA[
Strengthening of enterococcal biofilms by Esp 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.09.495547v1?rss=1</link>
<description><![CDATA[
Multidrug-resistant (MDR) Enterococcus faecalis are major causes of hospital-acquired infections. Numerous clinical strains harbor a large pathogenicity island that encodes enterococcal surface protein (Esp), which is suggested to promote biofilm production and virulence, but this remains controversial. To resolve this issue, we characterized the Esp N-terminal region, the portion implicated in biofilm production. Small angle X-ray scattering indicated that the N-terminal region had a globular head, which consisted of two DEv-Ig domains as visualized by X-ray crystallography, followed by an extended tail. The N-terminal region was not required for biofilm production but instead significantly strengthened biofilms against mechanical or degradative disruption, greatly increasing retention of Enterococcus within biofilms. Biofilm strengthening required low pH, which resulted in Esp unfolding, aggregating, and forming amyloid-like structures. The pH threshold for biofilm strengthening depended on protein stability. A truncated fragment of the first DEv-Ig domain, plausibly generated by a host protease, was the least stable and sufficient to strengthen biofilms at pH [&le;] 5.0, while the entire N-terminal region and intact Esp on the enterococcal surface was more stable and required a pH [&le;] 4.3. These results suggested a virulence role of Esp in strengthening enterococcal biofilms in acidic abiotic or host environments.
]]></description>
<dc:creator>Spiegelman, L.</dc:creator>
<dc:creator>Bahn-Suh, A.</dc:creator>
<dc:creator>Montano, E.</dc:creator>
<dc:creator>Zhang, L.</dc:creator>
<dc:creator>Hura, G.</dc:creator>
<dc:creator>Patras, K.</dc:creator>
<dc:creator>Kumar, A.</dc:creator>
<dc:creator>Tezcan, A.</dc:creator>
<dc:creator>Nizet, V.</dc:creator>
<dc:creator>Tsutakawa, S.</dc:creator>
<dc:creator>Ghosh, P.</dc:creator>
<dc:date>2022-06-09</dc:date>
<dc:identifier>doi:10.1101/2022.06.09.495547</dc:identifier>
<dc:title><![CDATA[Strengthening of enterococcal biofilms by Esp]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.22.497052v1?rss=1">
<title>
<![CDATA[
Wildebeest Herds on Rolling Hills: Flocking on Arbitrary Curved Surfaces 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.22.497052v1?rss=1</link>
<description><![CDATA[
The collective behavior of active agents, whether herds of wildebeest or microscopic actin filaments propelled by molecular motors, is an exciting frontier in biological and soft matter physics. Almost three decades ago, Toner and Tu developed a hydrodynamic theory of the collective action of flocks, or herds, that helped launch the modern field of active matter. One challenge faced when applying continuum active matter theories to living phenomena is the complex geometric structure of biological environments. Both macroscopic and microscopic herds move on asymmetric curved surfaces, like undulating grass plains or the surface layers of cells or embryos, which can render problems analytically intractable. In this work, we present a formulation of the Toner-Tu flocking theory that uses the finite element method to solve the governing equations on arbitrary curved surfaces. First, we test the developed formalism and its numerical implementation in channel flow with scattering obstacles and on cylindrical and spherical surfaces, comparing our results to analytical solutions. We then progress to surfaces with arbitrary curvature, moving beyond previously accessible problems to explore herding behavior on a variety of landscapes. Our approach allows the investigation of transients and dynamic solutions not revealed by analytic methods. It also enables versatile incorporation of new geometries and boundary conditions and efficient sweeps of parameter space. Looking forward, the work presented here lays the groundwork for a dialogue between Toner-Tu theory and data on collective motion in biologically-relevant geometries, from drone footage of migrating animal herds to movies of microscopic cytoskeletal flows within cells.
]]></description>
<dc:creator>Hueschen, C. L.</dc:creator>
<dc:creator>Dunn, A. R.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2022-06-25</dc:date>
<dc:identifier>doi:10.1101/2022.06.22.497052</dc:identifier>
<dc:title><![CDATA[Wildebeest Herds on Rolling Hills: Flocking on Arbitrary Curved Surfaces]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.24.497576v1?rss=1">
<title>
<![CDATA[
Comparative genomic insights into bacterial induction of larval settlement and metamorphosis in the upside-down jellyfish Cassiopea 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.24.497576v1?rss=1</link>
<description><![CDATA[
Bacterial biofilm is crucial in inducing the larval transition from pelagic to benthic environments for marine organisms. Bacteria can therefore dictate species distribution and success of the individual. Despite the importance of marine bacteria to animal ecology, the identity of inductive microbes for many invertebrates are unknown. We isolated bacteria belonging to multiple phyla are capable of inducing settlement and metamorphosis in the upside-down jellyfish Cassiopea xamachana. The most inductive isolates belonged to the genus Pseudoalteromonas, a marine bacterium known to induce the pelago-benthic transition in other marine invertebrates. In sequencing the genome of the isolated Pseudoalteromonas and an inductive Vibrio, we found biosynthetic pathways previously implicated in larval settlement were absent in these Cassiopea inducing taxa. Comparative analysis of the Pseudoalteromonas and Vibrio revealed shared genes that could underlie the inductive capacity of these two bacteria. Thus, C. xamachana are capable of responding to multiple bacterial species, but they may be responding to a common cue produced by multiple taxa. These findings could provide hints to the ecological success of C. xamachana compared to sympatric congeneric species within mangrove environments and provide avenues to investigate the evolution of animal-microbe interactions.
]]></description>
<dc:creator>Ohdera, A.</dc:creator>
<dc:creator>Medina, M.</dc:creator>
<dc:creator>Fitt, W.</dc:creator>
<dc:creator>Hofmann, D. K.</dc:creator>
<dc:creator>Attarwala, K.</dc:creator>
<dc:creator>Henry, R.</dc:creator>
<dc:creator>Wu, V.</dc:creator>
<dc:creator>Laird, H.</dc:creator>
<dc:date>2022-06-25</dc:date>
<dc:identifier>doi:10.1101/2022.06.24.497576</dc:identifier>
<dc:title><![CDATA[Comparative genomic insights into bacterial induction of larval settlement and metamorphosis in the upside-down jellyfish Cassiopea]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.06.26.495014v1?rss=1">
<title>
<![CDATA[
Genotyping, sequencing and analysis of 140,000 adults from the Mexico City Prospective Study 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.06.26.495014v1?rss=1</link>
<description><![CDATA[
The Mexico City Prospective Study (MCPS) is a prospective cohort of over 150,000 adults recruited two decades ago from the urban districts of Coyoacan and Iztapalapa in Mexico City. We generated genotype and exome sequencing data for all individuals, and whole genome sequencing for 10,000 selected individuals. We uncovered high levels of relatedness and substantial heterogeneity in ancestry composition across individuals. Most sequenced individuals had admixed Native American, European and African ancestry, with extensive admixture from indigenous groups in Central, Southern and South Eastern Mexico. Native Mexican segments of the genome had lower levels of coding variation, but an excess of homozygous loss of function variants compared with segments of African and European origin. We estimated population specific allele frequencies at 142 million genomic variants, with an effective sample size of 91,856 for Native Mexico at exome variants, all available via a public browser. Using whole genome sequencing, we developed an imputation reference panel which outperforms existing panels at common variants in individuals with high proportions of Central, South and South Eastern Native Mexican ancestry. Our work illustrates the value of genetic studies in populations with diverse ancestry and provides foundational imputation and allele frequency resources for future genetic studies in Mexico and in the United States where the Hispanic/Latino population is predominantly of Mexican descent.
]]></description>
<dc:creator>Ziyatdinov, A.</dc:creator>
<dc:creator>Torres, J.</dc:creator>
<dc:creator>Alegre-Diaz, J.</dc:creator>
<dc:creator>Backman, J.</dc:creator>
<dc:creator>Mbatchou, J.</dc:creator>
<dc:creator>Turner, M.</dc:creator>
<dc:creator>Gaynor, S. M.</dc:creator>
<dc:creator>Joseph, T.</dc:creator>
<dc:creator>Zou, Y.</dc:creator>
<dc:creator>Liu, D.</dc:creator>
<dc:creator>Wade, R.</dc:creator>
<dc:creator>Staples, J.</dc:creator>
<dc:creator>Panea, R.</dc:creator>
<dc:creator>Popov, A.</dc:creator>
<dc:creator>Maxwell, E.</dc:creator>
<dc:creator>Jones, M.</dc:creator>
<dc:creator>Garcia-Ortiz, H.</dc:creator>
<dc:creator>Ramirez-Reyes, R.</dc:creator>
<dc:creator>Santacruz-Benitez, R.</dc:creator>
<dc:creator>Nag, A.</dc:creator>
<dc:creator>Smith, K. R.</dc:creator>
<dc:creator>Regeneron Genetics Center,</dc:creator>
<dc:creator>Reppell, M.</dc:creator>
<dc:creator>Zollner, S.</dc:creator>
<dc:creator>Jorgenson, E.</dc:creator>
<dc:creator>Salerno, W.</dc:creator>
<dc:creator>Petrovski, S.</dc:creator>
<dc:creator>Overton, J.</dc:creator>
<dc:creator>Reid, J.</dc:creator>
<dc:creator>Thornton, T.</dc:creator>
<dc:creator>Abecasis, G.</dc:creator>
<dc:creator>Berumen, J.</dc:creator>
<dc:creator>Orozco-Orozco, L.</dc:creator>
<dc:creator>Collins, R.</dc:creator>
<dc:creator>Baras, A.</dc:creator>
<dc:creator>Hill, M. R.</dc:creator>
<dc:creator>Emberson, J. R.</dc:creator>
<dc:creator>Marchini, J.</dc:creator>
<dc:creator>Kuri-Morales, P.</dc:creator>
<dc:creator>Tapia-Conyer, R.</dc:creator>
<dc:date>2022-06-29</dc:date>
<dc:identifier>doi:10.1101/2022.06.26.495014</dc:identifier>
<dc:title><![CDATA[Genotyping, sequencing and analysis of 140,000 adults from the Mexico City Prospective Study]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.07.20.500857v1?rss=1">
<title>
<![CDATA[
Isoform- and ligand-specific modulation of the adhesion GPCR ADGRL3/Latrophilin3 by a synthetic binder 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.07.20.500857v1?rss=1</link>
<description><![CDATA[
Adhesion G protein-coupled receptors (aGPCRs) are cell-surface proteins with large extracellular regions that bind to multiple ligands to regulate key biological functions including neurodevelopment and organogenesis. Modulating a single function of a specific aGPCR isoform while affecting no other function and no other receptor is not trivial. Here, we engineered an antibody, termed LK30, that binds to the extracellular region of the aGPCR ADGRL3, and specifically acts as an agonist for ADGRL3 but not for its isoform, ADGRL1. The LK30/ADGRL3 complex structure revealed that the LK30 binding site on ADGRL3 overlaps with the binding site for an ADGRL3 ligand - teneurin. In cellular-adhesion assays, LK30 specifically broke the trans-cellular interaction of ADGRL3 with teneurin, but not with another ADGRL3 ligand - FLRT3. Our work provides proof of concept for the modulation of isoform- and ligand-specific aGPCR functions using unique tools, and thus establishes a foundation for the development of fine-tuned aGPCR-targeted therapeutics.
]]></description>
<dc:creator>Kordon, S. P.</dc:creator>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Adamska, J. M.</dc:creator>
<dc:creator>Bandekar, S. J.</dc:creator>
<dc:creator>Leon, K.</dc:creator>
<dc:creator>Adams, B.</dc:creator>
<dc:creator>Li, J.</dc:creator>
<dc:creator>Kossiakoff, A. A.</dc:creator>
<dc:creator>Arac, D.</dc:creator>
<dc:date>2022-07-21</dc:date>
<dc:identifier>doi:10.1101/2022.07.20.500857</dc:identifier>
<dc:title><![CDATA[Isoform- and ligand-specific modulation of the adhesion GPCR ADGRL3/Latrophilin3 by a synthetic binder]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.08.06.503044v1?rss=1">
<title>
<![CDATA[
Functional Ultrasound Imaging of the Human Spinal Cord 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.08.06.503044v1?rss=1</link>
<description><![CDATA[
The integration of functional responses in the human spinal cord into the nervous system is not well understood. Herein we demonstrate the first in-human functional ultrasound imaging (fUSI) of spinal cord response to epidural electrical stimulation. fUSI is a minimally invasive neuroimaging technique that can record blood flow at a level of spatial and temporal precision not previously achieved in the human spinal cord. By leveraging fUSI and epidural electrical spinal cord stimulation in patients who underwent surgery, we recorded and characterized for the first-time hemodynamic responses of the human spinal cord to an electrical neuromodulatory intervention commonly used for treating pain, and increasingly used for sensory-motor and autonomic functions. We found that the hemodynamic response to epidural stimulation reflects a spatiotemporal modulation of the spinal cord circuitry not previously recognized. The impact of this analytical capability is significant for several reasons. It offers a mechanism to assess blood flow changes with a new level of precision which can be obtained in real time under in vivo conditions. Additionally, we demonstrate that fUSI can successfully decode the spinal cord state in a single trial, which is of fundamental importance for developing real-time closed-loop neuromodulation systems. Also, we show that spinal cord hemodynamic changes due to epidural electrical stimulation occur primarily at the level of small vessels. Overall, our work is a critical step towards developing a vital technique to study spinal cord function and understand the potential effects of clinical neuromodulation for spinal cord and other neurological disorders.

One Sentence SummaryThe first in-human quantitative evaluation of spinal cord hemodynamics using functional ultrasound imaging (fUSI).
]]></description>
<dc:creator>Agyeman, K.</dc:creator>
<dc:creator>Lee, D. J.</dc:creator>
<dc:creator>Russin, J.</dc:creator>
<dc:creator>Kreydin, E. I.</dc:creator>
<dc:creator>Choi, W.</dc:creator>
<dc:creator>Abedi, A.</dc:creator>
<dc:creator>Edgerton, V. R.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Christopoulos, V.</dc:creator>
<dc:date>2022-08-06</dc:date>
<dc:identifier>doi:10.1101/2022.08.06.503044</dc:identifier>
<dc:title><![CDATA[Functional Ultrasound Imaging of the Human Spinal Cord]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.07.506997v1?rss=1">
<title>
<![CDATA[
A discrete mode of endosomal GPCR signaling that does not require β-arrestin 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.07.506997v1?rss=1</link>
<description><![CDATA[
Many GPCRs are now recognized to initiate a second phase of G protein (Gs) -dependent signaling through the cAMP cascade after endocytosis. A prevailing current view is that endocytosis-promoted signaling from GPCRs is inherently {beta}-arrestin-dependent because {beta}-arrestin is necessary for receptors to internalize and, for some GPCRs, it also promotes Gs activation on endosomes. Here we revise this view by showing that the vasoactive intestinal peptide receptor 1 (VIPR1), a prototypic secretin-family polypeptide hormone receptor, remains bound to {beta}-arrestin after endocytosis but does not require {beta}-arrestin either to internalize or to generate an endosomal signal. {beta}-arrestin instead resolves the endosomal signal into a temporally separated cAMP peak, and it does so by attenuating signaling from the plasma membrane without detectably affecting the endosomal response. The mechanistic basis for this location-specific difference in {beta}-arrestin function is the formation of distinct VIPR1/{beta}-arrestin complexes at each location. The signal-attenuating complex formed at the plasma membrane does not require GRK-mediated phosphorylation of receptors, while the signaling-neutral complex present on the endosome membrane, in contrast, is GRK-dependent. To our knowledge, the present results provide the first direct demonstration that endosomal GPCR signaling can occur in the complete absence of {beta}-arrestin. They also reveal a discrete role of {beta}-arrestin in sculpting the spatiotemporal profile of cellular GPCR - G protein signaling through the location-specific formation or remodeling of GPCR/{beta}-arrestin complexes.
]]></description>
<dc:creator>Blythe, E. E.</dc:creator>
<dc:creator>Von Zastrow, M.</dc:creator>
<dc:date>2022-09-08</dc:date>
<dc:identifier>doi:10.1101/2022.09.07.506997</dc:identifier>
<dc:title><![CDATA[A discrete mode of endosomal GPCR signaling that does not require β-arrestin]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.08.507086v1?rss=1">
<title>
<![CDATA[
CD4-binding site immunogens elicit heterologous anti-HIV-1 neutralizing antibodies in transgenic and wildtype animals 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.08.507086v1?rss=1</link>
<description><![CDATA[
Passive transfer of broadly neutralizing anti-HIV-1 antibodies (bNAbs) protects against infection, and therefore eliciting bNAbs by vaccination is a major goal of HIV-1 vaccine efforts. bNAbs that target the CD4-binding site (CD4bs) on HIV-1 Env are among the most broadly active, but to date, responses elicited against this epitope in vaccinated animals have lacked potency and breadth. We hypothesized that CD4bs bNAbs resembling the antibody IOMA might be easier to elicit than other CD4bs antibodies that exhibit higher somatic mutation rates, a difficult-to-achieve mechanism to accommodate Envs N276gp120 N-glycan, and rare 5-residue light chain complementarity determining region 3s (CDRL3s). As an initial test of this idea, we developed IOMA germline-targeting Env immunogens and evaluated a sequential immunization regimen in transgenic mice expressing germline-reverted IOMA. These mice developed CD4bs epitope-specific responses with heterologous neutralization, and cloned antibodies overcame neutralization roadblocks including accommodating the N276gp120 glycan, with some neutralizing selected HIV-1 strains more potently than IOMA. The immunization regimen also elicited CD4bs-specific responses in animals containing polyclonal antibody repertoires. Thus, germline-targeting of IOMA-class antibody precursors represents a potential vaccine strategy to induce CD4bs bNAbs.
]]></description>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>Hartweger, H.</dc:creator>
<dc:creator>Loewe, M.</dc:creator>
<dc:creator>van Schooten, J.</dc:creator>
<dc:creator>Ramos, V.</dc:creator>
<dc:creator>Oliviera, T. Y.</dc:creator>
<dc:creator>Nishimura, Y.</dc:creator>
<dc:creator>Koranda, N. S.</dc:creator>
<dc:creator>Wall, A.</dc:creator>
<dc:creator>Yao, K.-H.</dc:creator>
<dc:creator>Poston, D.</dc:creator>
<dc:creator>Gazumyan, A.</dc:creator>
<dc:creator>Wiatr, M.</dc:creator>
<dc:creator>Horning, M.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>Hoffmann, M. A.</dc:creator>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Abernathy, M. E.</dc:creator>
<dc:creator>Dam, K.-M. A.</dc:creator>
<dc:creator>Gao, H.</dc:creator>
<dc:creator>Gnanapragasam, P. N.</dc:creator>
<dc:creator>Kakutani, L. M.</dc:creator>
<dc:creator>Pavlovitch-Bedzyk, A. J.</dc:creator>
<dc:creator>Seaman, M. S.</dc:creator>
<dc:creator>Howarth, M.</dc:creator>
<dc:creator>McGuire, A. T.</dc:creator>
<dc:creator>Stamatatos, L.</dc:creator>
<dc:creator>Martin, M. A.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2022-09-12</dc:date>
<dc:identifier>doi:10.1101/2022.09.08.507086</dc:identifier>
<dc:title><![CDATA[CD4-binding site immunogens elicit heterologous anti-HIV-1 neutralizing antibodies in transgenic and wildtype animals]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.09.507372v1?rss=1">
<title>
<![CDATA[
Unsupervised Restoration of a Complex Learned Behavior After Large-Scale Neuronal Perturbation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.09.507372v1?rss=1</link>
<description><![CDATA[
Reliable execution of behaviors requires that brain circuits correct for variations in neuronal dynamics. Genetic perturbation of the majority of excitatory neurons in a brain region involved in song production in adult songbirds with stereotypical songs triggered severe degradation of their songs. The song fully recovered within two weeks, and substantial improvement occurred even when animals were prevented from singing during the recovery period, indicating that offline mechanisms enable recovery in an unsupervised manner. Song restoration was accompanied by increased excitatory synaptic inputs to unmanipulated neurons in the same region. A model inspired by the behavioral and electrophysiological findings suggests that a combination of unsupervised single-cell and population-level homeostatic plasticity rules can support the observed functional restoration after large-scale disruption of networks implementing sequential dynamics. In the model the sequence is restored through a parallel homeostatic process, rather than regrown serially, and predicts that sequences should recover in a saltatory fashion. Correspondingly, we observed such recovery in the songs of manipulated animals, with syllables that rapidly alternate between abnormal and normal durations from rendition to rendition until eventually they permanently settled into their original length. These observations indicate the existence of cellular and systems-level restorative mechanisms that ensure behavioral resilience.
]]></description>
<dc:creator>Wang, B.</dc:creator>
<dc:creator>Torok, Z.</dc:creator>
<dc:creator>Duffy, A.</dc:creator>
<dc:creator>Bell, D.</dc:creator>
<dc:creator>Wongso, S.</dc:creator>
<dc:creator>Velho, T.</dc:creator>
<dc:creator>Fairhall, A.</dc:creator>
<dc:creator>Lois, C.</dc:creator>
<dc:date>2022-09-10</dc:date>
<dc:identifier>doi:10.1101/2022.09.09.507372</dc:identifier>
<dc:title><![CDATA[Unsupervised Restoration of a Complex Learned Behavior After Large-Scale Neuronal Perturbation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.16.508155v1?rss=1">
<title>
<![CDATA[
Cells in the Polyaneuploid Cancer Cell (PACC) state have increased metastatic potential 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.16.508155v1?rss=1</link>
<description><![CDATA[
Although metastasis is the leading cause of cancer deaths, it is quite rare at the cellular level. Only a rare subset of cancer cells ([~]1 in 1.5 billion) can complete the entire metastatic cascade: invasion, intravasation, survival in the circulation, extravasation, and colonization (i.e. are metastasis competent). We propose that cells engaging a Polyaneuploid Cancer Cell (PACC) phenotype are metastasis competent. PACCs are enlarged, non-dividing cells with increased genomic content that form in response to stress. Single-cell tracking using time-lapse microscopy reveals that PACCs are more motile than nonPACCs. Additionally, PACCs exhibit increased capacity for environment-sensing and directional migration in chemotactic environments, predicting successful invasion. Magnetic Twisting Cytometry and Atomic Force Microscopy reveal that cells in the PACC state display hyper-elastic properties like increased peripheral deformability and maintained peri-nuclear cortical integrity that predict successful intravasation and extravasation. Furthermore, four orthogonal methods reveal that PACCs have increased expression of Vimentin, a known hyper-elastic biomolecule. Lastly, anoikis-resistance assays and detection of PACCs in the blood of a patient with metastatic castrate-resistant prostate cancer using a selection- free circulating tumor cell detection platform reveal that PACCs are capable of surviving in the circulation. Taken together with the knowledge that PACCs are capable of eventual depolyploidization and progeny formation (as a potential route to colonization), these data support PACCs as candidate metastasis-competent cells worthy of further analysis.
]]></description>
<dc:creator>Mallin, M. M.</dc:creator>
<dc:creator>Kim, N.</dc:creator>
<dc:creator>Choudhury, M. I.</dc:creator>
<dc:creator>Lee, S. J.</dc:creator>
<dc:creator>An, S. S.</dc:creator>
<dc:creator>Sun, S. X.</dc:creator>
<dc:creator>Konstantopoulos, K.</dc:creator>
<dc:creator>Pienta, K. J.</dc:creator>
<dc:creator>Amend, S. R.</dc:creator>
<dc:date>2022-09-19</dc:date>
<dc:identifier>doi:10.1101/2022.09.16.508155</dc:identifier>
<dc:title><![CDATA[Cells in the Polyaneuploid Cancer Cell (PACC) state have increased metastatic potential]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.09.26.509520v1?rss=1">
<title>
<![CDATA[
Ten new high-quality genome assemblies for diverse bioenergy sorghum genotypes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.09.26.509520v1?rss=1</link>
<description><![CDATA[
Sorghum (Sorghum bicolor (L.) Moench) is an agriculturally and economically important staple crop that has immense potential as a bioenergy feedstock due to its relatively high productivity on marginal lands. To capitalize on and further improve sorghum as a potential source of sustainable biofuel, it is essential to understand the genomic mechanisms underlying complex traits related to yield, composition, and environmental adaptations. Expanding on a recently developed mapping population, we generated de novo genome assemblies for 10 parental genotypes from this population and identified a comprehensive set of over 24 thousand large structural variants (SVs) and over 10.5 million single nucleotide polymorphisms (SNPs).These resources can be integrated into both ongoing and future mapping and trait discovery for sorghum and its myriad uses including food, feed, bioenergy, and increasingly as a carbon dioxide removal mechanism. We show that SVs and nonsynonymous SNPs are enriched in different gene categories, emphasizing the need for long read sequencing in crop species to identify novel variation. Furthermore, we highlight SVs and SNPs occurring in genes and pathways with known associations to critical bioenergy-related phenotypes and characterize the landscape of genetic differences between sweet and cellulosic genotypes.
]]></description>
<dc:creator>Voelker, W. G.</dc:creator>
<dc:creator>Krishnan, K.</dc:creator>
<dc:creator>Chougule, K.</dc:creator>
<dc:creator>Alexander, L. C.</dc:creator>
<dc:creator>Lu, Z.</dc:creator>
<dc:creator>Olson, A.</dc:creator>
<dc:creator>Ware, D.</dc:creator>
<dc:creator>Songsomboon, K.</dc:creator>
<dc:creator>Ponce, C. M.</dc:creator>
<dc:creator>Brenton, Z.</dc:creator>
<dc:creator>Boatwright, J. L.</dc:creator>
<dc:creator>Cooper, E. A.</dc:creator>
<dc:date>2022-09-27</dc:date>
<dc:identifier>doi:10.1101/2022.09.26.509520</dc:identifier>
<dc:title><![CDATA[Ten new high-quality genome assemblies for diverse bioenergy sorghum genotypes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.07.511265v1?rss=1">
<title>
<![CDATA[
Drosophila epidermal cells are intrinsically mechanosensitive and drive nociceptive behavioral outputs 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.07.511265v1?rss=1</link>
<description><![CDATA[
Somatosensory neurons (SSNs) that detect and transduce mechanical, thermal, and chemical stimuli densely innervate an animals skin. However, although epidermal cells provide the first point of contact for sensory stimuli. our understanding of roles that epidermal cells play in SSN function, particularly nociception, remains limited. Here, we show that stimulating Drosophila epidermal cells elicits activation of SSNs including nociceptors and triggers a variety of behavior outputs, including avoidance and escape. Further, we find that epidermal cells are intrinsically mechanosensitive and that epidermal mechanically evoked calcium responses require the store-operated calcium channel Orai. Epidermal cell stimulation augments larval responses to acute nociceptive stimuli and promotes prolonged hypersensitivity to subsequent mechanical stimuli. Hence, epidermal cells are key determinants of nociceptive sensitivity and sensitization, acting as primary sensors of noxious stimuli that tune nociceptor output and drive protective behaviors.
]]></description>
<dc:creator>Yoshino, J.</dc:creator>
<dc:creator>Mali, S.</dc:creator>
<dc:creator>Williams, C.</dc:creator>
<dc:creator>Morita, T.</dc:creator>
<dc:creator>Emerson, C.</dc:creator>
<dc:creator>Arp, C.</dc:creator>
<dc:creator>Sophie, M.</dc:creator>
<dc:creator>Yin, C.</dc:creator>
<dc:creator>The, L.</dc:creator>
<dc:creator>Chikaya, H.</dc:creator>
<dc:creator>Motoyoshi, M.</dc:creator>
<dc:creator>Ishii, K.</dc:creator>
<dc:creator>Emoto, K.</dc:creator>
<dc:creator>Bautista, D. M.</dc:creator>
<dc:creator>Parrish, J. Z.</dc:creator>
<dc:date>2022-10-10</dc:date>
<dc:identifier>doi:10.1101/2022.10.07.511265</dc:identifier>
<dc:title><![CDATA[Drosophila epidermal cells are intrinsically mechanosensitive and drive nociceptive behavioral outputs]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-10-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.10.31.514511v1?rss=1">
<title>
<![CDATA[
The Plasmodium falciparum apicoplast cysteine desulfurase provides sulfur for both iron sulfur cluster assembly and tRNA modification 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.10.31.514511v1?rss=1</link>
<description><![CDATA[
Iron sulfur clusters (FeS) are ancient and ubiquitous protein cofactors that play fundamental roles in many aspects of cell biology. These cofactors cannot be scavenged or trafficked within a cell and thus must be synthesized in any subcellular compartment where they are required. We examined the FeS synthesis proteins found in the relict plastid organelle, called the apicoplast, of the human malaria parasite Plasmodium falciparum. Using a chemical bypass method, we deleted four of the FeS pathway proteins involved in sulfur acquisition and cluster assembly and demonstrated that they are all essential for parasite survival. However, the effect that these deletions had on the apicoplast organelle differed. Deletion of the cysteine desulfurase SufS led to disruption of the apicoplast organelle and loss of the organellar genome, whereas the other deletions did not affect organelle maintenance. Ultimately, we discovered that the requirement of SufS for organelle maintenance is not driven by its role in FeS biosynthesis, but rather, by its function in generating sulfur for use by MnmA, a tRNA modifying enzyme that we localized to the apicoplast. By complementing the activity of the parasite MnmA and SufS with a bacterial MnmA and its cognate cysteine desulfurase, we showed that the parasite SufS provides sulfur for both FeS biosynthesis and tRNA modification in the apicoplast. The dual role of parasite SufS is likely to be found in other plastid-containing organisms and highlights the central role of this enzyme in plastid biology.
]]></description>
<dc:creator>Prigge, S. T.</dc:creator>
<dc:creator>Swift, R. P.</dc:creator>
<dc:creator>Elahi, R.</dc:creator>
<dc:creator>Rajaram, K.</dc:creator>
<dc:creator>Liu, H. B.</dc:creator>
<dc:date>2022-11-01</dc:date>
<dc:identifier>doi:10.1101/2022.10.31.514511</dc:identifier>
<dc:title><![CDATA[The Plasmodium falciparum apicoplast cysteine desulfurase provides sulfur for both iron sulfur cluster assembly and tRNA modification]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.11.16.516796v1?rss=1">
<title>
<![CDATA[
Root Walker: an automated pipeline for large scale quantification of early root growth responses at high spatial and temporal resolution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.11.16.516796v1?rss=1</link>
<description><![CDATA[
Plants are sessile organisms that constantly adapt to their changing environment. The root is exposed to numerous environmental signals ranging from nutrients and water to microbial molecular patterns. These signals can trigger distinct responses including the rapid increase or decrease of root growth. Consequently, using root growth as a readout for signal perception can help decipher which external cues are perceived by roots, and how these signals are integrated. To date, studies measuring root growth responses using large numbers of roots have been limited by a lack of high-throughput image acquisition, poor scalability of analytical methods, or low spatiotemporal resolution. Here, we developed the Root Walker pipeline, which uses automated microscopes to acquire time-series images of many roots exposed to controlled treatments with high-spatiotemporal-resolution, in conjunction with fast and automated image analysis software. We demonstrate the power of Root Walker by quantifying root growth rate responses at different time and throughput scales upon treatments with natural auxin, and upon treatment with two mitogen-associated protein kinase cascade inhibitors. We find a concentration-dependent root growth response to auxin and reveal the specificity of one MAPK inhibitor. We further demonstrate the ability of Root Walker for conducting genetic screens by performing a genome wide association study on 260 accessions under 2 weeks. This revealed known and unknown root growth regulators. Root Walker promises to be a useful toolkit for the plant science community, allowing large-scale screening of root growth dynamics for a variety of purposes, including genetic screens for root sensing and root growth response mechanisms.
]]></description>
<dc:creator>Platre, M. P.</dc:creator>
<dc:creator>Halvorson, Z.</dc:creator>
<dc:creator>Mehta, P.</dc:creator>
<dc:creator>Brent, L.</dc:creator>
<dc:creator>Matias, G. F.</dc:creator>
<dc:creator>Faizi, K.</dc:creator>
<dc:creator>Busch, W.</dc:creator>
<dc:date>2022-11-17</dc:date>
<dc:identifier>doi:10.1101/2022.11.16.516796</dc:identifier>
<dc:title><![CDATA[Root Walker: an automated pipeline for large scale quantification of early root growth responses at high spatial and temporal resolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2022.12.15.520299v1?rss=1">
<title>
<![CDATA[
Tools for comprehensive reconstruction and analysis of Drosophila motor circuits 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2022.12.15.520299v1?rss=1</link>
<description><![CDATA[
Like the vertebrate spinal cord, the insect ventral nerve cord (VNC) mediates limb sensation and motor control. Here, we apply automated tools for electron microscopy volume alignment, neuron segmentation, and synapse prediction toward creating a connectome of an adult female Drosophila VNC. To interpret a connectome, it is crucial to know its relationship with the rest of the body. We therefore mapped the muscle targets of leg and wing motor neurons in the connectome by comparing their morphology to genetic driver lines, dye fills, and X-ray nano-tomography of the fly leg and wing. Knowing the outputs of the connectome allowed us to identify neural circuits that coordinate the wings and legs during escape takeoff. We provide the reconstruction of VNC circuits and motor neuron atlas, along with tools for programmatic and interactive access, as community resources to support experimental and theoretical studies of how the fly nervous system controls behavior.
]]></description>
<dc:creator>Azevedo, A. W.</dc:creator>
<dc:creator>Lesser, E.</dc:creator>
<dc:creator>Mark, B.</dc:creator>
<dc:creator>Phelps, J. S.</dc:creator>
<dc:creator>Elabbady, L.</dc:creator>
<dc:creator>Kuroda, S.</dc:creator>
<dc:creator>Sustar, A. E.</dc:creator>
<dc:creator>Moussa, A. J.</dc:creator>
<dc:creator>Kandelwal, A.</dc:creator>
<dc:creator>Dallmann, C. J.</dc:creator>
<dc:creator>Agrawal, S.</dc:creator>
<dc:creator>Lee, S.-Y. J.</dc:creator>
<dc:creator>Pratt, B. G.</dc:creator>
<dc:creator>Cook, A.</dc:creator>
<dc:creator>Skutt-Kakari, K.</dc:creator>
<dc:creator>Gerhard, S.</dc:creator>
<dc:creator>Lu, R.</dc:creator>
<dc:creator>Kemnitz, N.</dc:creator>
<dc:creator>Lee, K.</dc:creator>
<dc:creator>Halageri, A.</dc:creator>
<dc:creator>Castro, M.</dc:creator>
<dc:creator>Ih, D.</dc:creator>
<dc:creator>Gager, J.</dc:creator>
<dc:creator>Tammam, M.</dc:creator>
<dc:creator>Dorkenwald, S.</dc:creator>
<dc:creator>Collman, F. C.</dc:creator>
<dc:creator>Schneider-Mizell, C. M.</dc:creator>
<dc:creator>Brittain, D.</dc:creator>
<dc:creator>Jordan, C. S.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:creator>Pacureanu, A.</dc:creator>
<dc:creator>Seung, H. S.</dc:creator>
<dc:creator>Macrina, T.</dc:creator>
<dc:creator>Lee, W.-C. A.</dc:creator>
<dc:creator>Tuthill, J. C.</dc:creator>
<dc:date>2022-12-15</dc:date>
<dc:identifier>doi:10.1101/2022.12.15.520299</dc:identifier>
<dc:title><![CDATA[Tools for comprehensive reconstruction and analysis of Drosophila motor circuits]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-12-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.12.523500v1?rss=1">
<title>
<![CDATA[
spinDrop: a droplet microfluidic platform to maximise single-cell sequencing information content 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.12.523500v1?rss=1</link>
<description><![CDATA[
Droplet microfluidic methods have massively increased the throughput of single-cell sequencing campaigns. The benefit of scale-up is, however, accompanied by increased background noise when processing challenging samples and the overall RNA capture efficiency is lower. These drawbacks stem from the lack of strategies to enrich for high-quality material or specific cell types at the moment of cell encapsulation and the absence of implementable multi-step enzymatic processes that increase capture. Here we alleviate both bottlenecks using fluorescence-activated droplet sorting to enrich for droplets that contain single viable cells, intact nuclei, fixed cells or target cell types and use reagent addition to droplets by picoinjection to perform multi-step lysis and reverse transcription. Our methodology increases gene detection rates fivefold, while reducing background noise by up to half. We harness these unique properties to deliver a high-quality molecular atlas of mouse brain development, despite starting with highly damaged input material, and provide an atlas of nascent RNA transcription during mouse organogenesis. Our method is broadly applicable to other droplet-based workflows to deliver sensitive and accurate single-cell profiling at a reduced cost.
]]></description>
<dc:creator>de Jonghe, J.</dc:creator>
<dc:creator>Kaminski, T. S.</dc:creator>
<dc:creator>Morse, D.</dc:creator>
<dc:creator>Tabaka, M.</dc:creator>
<dc:creator>Ellermann, A. L.</dc:creator>
<dc:creator>Kohler, T. N.</dc:creator>
<dc:creator>Amadei, G.</dc:creator>
<dc:creator>Handford, C.</dc:creator>
<dc:creator>Findlay, G.</dc:creator>
<dc:creator>Zernicka-Goetz, M.</dc:creator>
<dc:creator>Teichmann, S.</dc:creator>
<dc:creator>Hollfelder, F.</dc:creator>
<dc:date>2023-01-13</dc:date>
<dc:identifier>doi:10.1101/2023.01.12.523500</dc:identifier>
<dc:title><![CDATA[spinDrop: a droplet microfluidic platform to maximise single-cell sequencing information content]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.01.27.525985v1?rss=1">
<title>
<![CDATA[
Structural characterization of HIV-1 Env heterotrimers bound to one or two CD4 receptors reveals intermediate Env conformations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.01.27.525985v1?rss=1</link>
<description><![CDATA[
HIV-1 envelope (Env) exhibits distinct conformational changes in response to host receptor (CD4) engagement. Env, a trimer of gp120/gp41 heterodimers, has been structurally characterized in a closed, prefusion conformation with closely associated gp120s and coreceptor binding sites on gp120 V3 hidden by V1V2 loops, and in fully-saturated CD4-bound open Env conformations with changes including outwardly rotated gp120s and displaced V1V2 loops. To investigate changes resulting from sub-stoichiometric CD4 binding, we solved 3.4[A] and 3.9[A] single-particle cryo-EM structures of soluble, native-like Envs bound to one or two CD4 molecules. Env trimer bound to one CD4 adopted the closed, prefusion Env state. When bound to two CD4s, the CD4-bound gp120s exhibited an open Env conformation including a four-stranded gp120 bridging sheet and displaced gp120 V1V2 loops that expose the coreceptor sites on V3. The third gp120 adopted an intermediate, occluded-open state that included gp120 outward rotation but maintained the prefusion, three-stranded gp120 bridging sheet and showed only partial V1V2 displacement and V3 exposure. We conclude that engagement of one CD4 molecule was insufficient to stimulate CD4-induced conformational changes, while binding two CD4 molecules led to Env opening in CD4-bound protomers only. Together, these results illuminate HIV-1 Env intermediate conformations and illustrate the structural plasticity of HIV-1 Env.
]]></description>
<dc:creator>Dam, K.-M. A.</dc:creator>
<dc:creator>Fan, C.</dc:creator>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2023-01-28</dc:date>
<dc:identifier>doi:10.1101/2023.01.27.525985</dc:identifier>
<dc:title><![CDATA[Structural characterization of HIV-1 Env heterotrimers bound to one or two CD4 receptors reveals intermediate Env conformations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-01-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.10.528036v1?rss=1">
<title>
<![CDATA[
Evolution of connectivity architecture in the Drosophila mushroom body 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.10.528036v1?rss=1</link>
<description><![CDATA[
Brain evolution has primarily been studied at the macroscopic level by comparing the relative size of homologous brain centers between species. How neuronal circuits change at the cellular level over evolutionary time remains largely unanswered. Here, using a phylogenetically informed framework, we compare the olfactory circuits of three closely related Drosophila species that differ radically in their chemical ecology: the generalists Drosophila melanogaster and Drosophila simulans that feed on fermenting fruit, and Drosophila sechellia that specializes on ripe noni fruit. We examine a central part of the olfactory circuit that has not yet been investigated in these species -- the connections between the projection neurons of the antennal lobe and the Kenyon cells of the mushroom body, an associative brain center -- to identify species-specific connectivity patterns. We found that neurons encoding food odors -- the DC3 neurons in D. melanogaster and D. simulans and the DL2d neurons in D. sechellia -- connect more frequently with Kenyon cells, giving rise to species-specific biases in connectivity. These species-specific differences in connectivity reflect two distinct neuronal phenotypes: in the number of projection neurons or in the number of presynaptic boutons formed by individual projection neurons. Finally, behavioral analyses suggest that such increased connectivity enhances learning performance in an associative task. Our study shows how fine-grained aspects of connectivity architecture in an associative brain center can change during evolution to reflect the chemical ecology of a species.
]]></description>
<dc:creator>Caron, S. J. C.</dc:creator>
<dc:creator>Ellis, K. E.</dc:creator>
<dc:creator>Smihula, H.</dc:creator>
<dc:creator>Ganguli, I.</dc:creator>
<dc:creator>Vigato, E.</dc:creator>
<dc:creator>Bervoets, S.</dc:creator>
<dc:creator>Auer, T. O.</dc:creator>
<dc:creator>Benton, R.</dc:creator>
<dc:creator>Litwin Kumar, A.</dc:creator>
<dc:date>2023-02-12</dc:date>
<dc:identifier>doi:10.1101/2023.02.10.528036</dc:identifier>
<dc:title><![CDATA[Evolution of connectivity architecture in the Drosophila mushroom body]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.10.528055v1?rss=1">
<title>
<![CDATA[
Encoding of predictive associations in human prefrontal and medial temporal neurons during Pavlovian conditioning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.10.528055v1?rss=1</link>
<description><![CDATA[
Pavlovian conditioning is thought to involve the formation of learned associations between stimuli and values, and between stimuli and specific features of outcomes. Here we leveraged human single neuron recordings in ventromedial prefrontal, dorsomedial frontal, hippocampus and amygdala neurons while patients performed a sequential Pavlovian conditioning task containing both stimulus-value and stimulus-stimulus associations. Neurons in the ventromedial prefrontal cortex encoded predictive value along with the amygdala, but also encoded predictions about the identity of stimuli that would subsequently be presented, suggesting a role for neurons in this region in encoding predictive information beyond value. Unsigned error signals were found in dorsomedial prefrontal areas and hippocampus, potentially supporting learning of non-value related outcome features. Our findings implicate distinct human prefrontal and medial temporal neuronal populations in mediating predictive associations which could partially support model-based mechanisms during Pavlovian conditioning.

Significance statementPavlovian conditioning is a fundamental form of learning, allowing organisms to associate stimuli and outcomes. Recent Pavlovian work suggests that phenomena such as devaluation sensitivity and sensory preconditioning can be explained by a model-based learning framework. How human neurons perform model-based learning during Pavlovian conditioning is still an open question. We recorded single neurons from epilepsy patients during a two-step Pavlovian conditioning task and found that ventromedial prefrontal neurons encoded expected rewards along with amygdala neurons, but also predicted the identity of upcoming stimuli as required for model-based cognition. Additionally, medial frontal neurons were found to encode error signals that could be used for stimulus-outcome learning. This is the first study mapping model-based computations during Pavlovian conditioning in human neurons.
]]></description>
<dc:creator>Aquino, T. G.</dc:creator>
<dc:creator>Courellis, H. S.</dc:creator>
<dc:creator>Mamelak, A.</dc:creator>
<dc:creator>Rutishauser, U.</dc:creator>
<dc:creator>O'Doherty, J.</dc:creator>
<dc:date>2023-02-12</dc:date>
<dc:identifier>doi:10.1101/2023.02.10.528055</dc:identifier>
<dc:title><![CDATA[Encoding of predictive associations in human prefrontal and medial temporal neurons during Pavlovian conditioning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.21.525740v1?rss=1">
<title>
<![CDATA[
Discovery and characterization of a chemical probe targeting the zinc-finger ubiquitin-binding domain of HDAC6 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.21.525740v1?rss=1</link>
<description><![CDATA[
Histone deacetylase 6 (HDAC6) inhibition is an attractive strategy for treating numerous cancers, and HDAC6 catalytic inhibitors are currently in clinical trials. The HDAC6 zinc-finger ubiquitin-binding domain (UBD) binds free C-terminal diglycine motifs of unanchored ubiquitin polymer chains and protein aggregates, playing an important role in autophagy and aggresome assembly. However, targeting this domain with small molecule antagonists remains an underdeveloped avenue of HDAC6-focused drug discovery. We report SGC-UBD253 (25), a chemical probe potently targeting HDAC6-UBD in vitro with selectivity over nine other UBDs, except for weak USP16 binding. In cells, 25 is an effective antagonist of HDAC6-UBD at 1 {micro}M, with marked proteome-wide selectivity. We identified SGC-UBD253N (32), a methylated derivative of 25 which is 300-fold less active, serving as a negative control. Together, 25 and 32 could enable further exploration of the biological function of the HDAC6 UBD and investigation of the therapeutic potential of targeting this domain.
]]></description>
<dc:creator>Harding, R. J.</dc:creator>
<dc:creator>Franzoni, I.</dc:creator>
<dc:creator>Mann, M. K.</dc:creator>
<dc:creator>Szewczyk, M.</dc:creator>
<dc:creator>Mirabi, B.</dc:creator>
<dc:creator>Owens, D. D.</dc:creator>
<dc:creator>Ackloo, S.</dc:creator>
<dc:creator>Scheremetjew, A.</dc:creator>
<dc:creator>Juarez-Ornelas, K. A.</dc:creator>
<dc:creator>Sanichar, R.</dc:creator>
<dc:creator>Baker, R. J.</dc:creator>
<dc:creator>Dank, C.</dc:creator>
<dc:creator>Brown, P. J.</dc:creator>
<dc:creator>Barsyte-Lovejoy, D.</dc:creator>
<dc:creator>Santhakumar, V.</dc:creator>
<dc:creator>Schapira, M.</dc:creator>
<dc:creator>Lautens, M.</dc:creator>
<dc:creator>Arrowsmith, C. H.</dc:creator>
<dc:date>2023-02-22</dc:date>
<dc:identifier>doi:10.1101/2023.02.21.525740</dc:identifier>
<dc:title><![CDATA[Discovery and characterization of a chemical probe targeting the zinc-finger ubiquitin-binding domain of HDAC6]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.02.28.530560v1?rss=1">
<title>
<![CDATA[
Migration and establishment of progenitor pool of melanocytes is governed by SEMA3E-PLXND1 signaling 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.02.28.530560v1?rss=1</link>
<description><![CDATA[
Vertebrate pigmentation is an outcome of an interplay of several signaling pathways that result in immense diversity of pigment patterns observed across the animal kingdom. Transitory nature of these signaling events impedes deciphering pathways that control migration and establishment of melanocyte stem cells (McSC), necessary for pigment patterning. Using zebrafish and cultured mammalian melanocytes, we uncover a hitherto unknown role for Plexin D1 signaling. This pathway directs migration by F-actin modulation and further dictates subsequent functional states of melanocytes through a transcriptional response. In zebrafish, abrogation of PLXND1 derails melanocyte migration and reduces mid-line melanophores emerging from the regeneration competent McSC pool. In cultured melanocytes, activation of PLXND1 by the ligand semaphorin 3E reduces the velocity of migration, influences directional correlation, and promotes movement towards positive cues such as SCF. PLXND1 activation results in EGFR signaling necessary for McSC establishment, and induces GNAS, an effector of MC1R pathway involved in melanocyte maturation. Identification of this long-range secreted negative chemotactic signaling provides a missing player and enriches reaction diffusion model for pigment patterning.
]]></description>
<dc:creator>Natarajan, V. T.</dc:creator>
<dc:creator>Subramaniam, Y.</dc:creator>
<dc:creator>Sharma, B.</dc:creator>
<dc:creator>Aggarwal, A.</dc:creator>
<dc:creator>Raja, D. A.</dc:creator>
<dc:creator>Gupta, I.</dc:creator>
<dc:creator>Ghazi, M.</dc:creator>
<dc:creator>Sivasubbu, S.</dc:creator>
<dc:date>2023-03-02</dc:date>
<dc:identifier>doi:10.1101/2023.02.28.530560</dc:identifier>
<dc:title><![CDATA[Migration and establishment of progenitor pool of melanocytes is governed by SEMA3E-PLXND1 signaling]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.01.530675v1?rss=1">
<title>
<![CDATA[
Bacterial Form I' rubisco has smaller carbon isotope fractionation than its Form I counterpart 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.01.530675v1?rss=1</link>
<description><![CDATA[
Form I rubiscos evolved in Cyanobacteria [&ge;]2.5 billion years ago and are enzymatically unique due to the presence of small subunits (RbcS) that cap both ends of an octameric large subunit (RbcL) rubisco assembly to form a hexadecameric (L8S8) holoenzyme. Although RbcS was previously thought to be integral to Form I rubisco stability, the recent discovery of a closely related sister clade of octameric rubiscos (Form I; L8) demonstrates that the enzyme complex assembles without small subunits (Banda et al. 2020). Rubisco also displays a kinetic isotope effect (KIE) where the 3PG product is depleted in 13C relative to 12C. In Cyanobacteria only two Form I KIE measurements exist, making interpretation of bacterial carbon isotope data difficult. To aid comparison, we measured in vitro the KIEs of Form I (Candidatus Promineofilum breve) and Form I (Synechococcus elongatus PCC 6301) rubiscos and found the KIE to be smaller in the L8 rubisco (16.25 {+/-} 1.36{per thousand} vs. 22.42 {+/-} 2.37{per thousand} respectively). Therefore, while small subunits may not be necessary for protein stability, they may affect the KIE. Our findings may provide insight into the function of RbcS and allow more refined interpretation of environmental carbon isotope data.
]]></description>
<dc:creator>Wang, R. Z.</dc:creator>
<dc:creator>Liu, A. K.</dc:creator>
<dc:creator>Banda, D. M.</dc:creator>
<dc:creator>Fischer, W. W.</dc:creator>
<dc:creator>Shih, P. M.</dc:creator>
<dc:date>2023-03-02</dc:date>
<dc:identifier>doi:10.1101/2023.03.01.530675</dc:identifier>
<dc:title><![CDATA[Bacterial Form I' rubisco has smaller carbon isotope fractionation than its Form I counterpart]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.29.534836v1?rss=1">
<title>
<![CDATA[
Hyperconnectivity of two separate long-range cholinergic systems contributes to the reorganization of the brain functional connectivity during nicotine withdrawal in male mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.29.534836v1?rss=1</link>
<description><![CDATA[
Chronic nicotine results in dependence with withdrawal symptoms upon discontinuation of use, through desensitization of nicotinic acetylcholine receptors and altered cholinergic neurotransmission. Nicotine withdrawal is associated with increased whole-brain functional connectivity and decreased network modularity, however, the role of cholinergic neurons in those changes is unknown. To identify the contribution of nicotinic receptors and cholinergic regions to changes in the functional network, we analyzed the contribution of the main cholinergic regions to brain-wide activation of the immediate early-gene FOS during withdrawal in male mice and correlated these changes with the expression of nicotinic receptor mRNA throughout the brain. We show that the main functional connectivity modules included the main long-range cholinergic regions, which were highly synchronized with the rest of the brain. However, despite this hyperconnectivity they were organized into two anticorrelated networks that were separated into basal forebrain projecting and brainstem-thalamic projecting cholinergic regions, validating a long-standing hypothesis of the organization of the brain cholinergic systems. Moreover, baseline (without nicotine) expression of Chrna2, Chrna3, Chrna10, and Chrnd mRNA of each brain region correlated with withdrawal-induced changes in FOS expression. Finally, by mining the Allen Brain mRNA expression database, we were able to identify 1755 gene candidates and three pathways (Sox2-Oct4-Nanog, JAK-STAT, and MeCP2-GABA) that may contribute to nicotine withdrawal-induced FOS expression. These results identify the dual contribution of the basal forebrain and brainstem-thalamic cholinergic systems to whole-brain functional connectivity during withdrawal; and identify nicotinic receptors and novel cellular pathways that may be critical for the transition to nicotine dependence.

Significance StatementDiscontinuation of nicotine use in dependent users is associated with increased whole-brain activation and functional connectivity and leads to withdrawal symptoms. Here we investigated the contribution of the nicotinic cholinergic receptors and main cholinergic projecting brain areas in the whole-brain changes associated with withdrawal. This not only allowed us to visualize and confirm the previously described duality of the cholinergic brain system using this novel methodology, but also identify nicotinic receptors together with 1751 other genes that contribute, and could thus be targets for treatments against, nicotine withdrawal and dependence.
]]></description>
<dc:creator>Carrette, L. L. G.</dc:creator>
<dc:creator>Kimbrough, A.</dc:creator>
<dc:creator>Davoudian, P. A.</dc:creator>
<dc:creator>Kwan, A. C.</dc:creator>
<dc:creator>Collazo, A.</dc:creator>
<dc:creator>George, O.</dc:creator>
<dc:date>2023-03-31</dc:date>
<dc:identifier>doi:10.1101/2023.03.29.534836</dc:identifier>
<dc:title><![CDATA[Hyperconnectivity of two separate long-range cholinergic systems contributes to the reorganization of the brain functional connectivity during nicotine withdrawal in male mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.03.31.535168v1?rss=1">
<title>
<![CDATA[
Tunable photoinitiated hydrogel microspheres for direct quantification of cell-generated forces in complex three-dimensional environments 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.03.31.535168v1?rss=1</link>
<description><![CDATA[
We present a high-throughput method using standard laboratory equipment and microfluidics to produce cellular force microscopy probes with controlled size and elastic modulus. Mechanical forces play crucial roles in cell biology but quantifying these forces in physiologically relevant systems remains challenging due to the complexity of the native cell environment. Polymerized hydrogel microspheres offer great promise for interrogating the mechanics of processes inaccessible to classic force microscopy methods. However, despite significant recent advances, their small size and large surface-to-volume ratio impede the high-yield production of probes with tunable, monodisperse distributions of size and mechanical properties.

To overcome these limitations, we use a flow-focusing microfluidic device to generate large quantities of droplets with highly reproducible, adjustable radii. These droplets contain acrylamide gel precursor and the photoinitiator Lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) as a source of free radicals. LAP provides fine control over microsphere polymerization due to its high molar absorptivity at UV wavelengths and moderate water solubility. The polymerized microspheres can be functionalized with different conjugated extracellular matrix proteins and embedded with fluorescent nanobeads to promote cell attachment and track microsphere deformation.

As proof of concept, we measure the mechanical forces generated by a monolayer of vascular endothelial cells engulfing functionalized microspheres. Individual nanobead motions are tracked in 3D and analyzed to determine the 3D traction forces within seconds and without the need for solving an ill-posed inverse problem. These results reveal that the cell monolayer collectively exerts strong radial compression and subtle lateral distortions on the encapsulated probe.
]]></description>
<dc:creator>Garcia-Herreros, A.</dc:creator>
<dc:creator>Yeh, Y.-T.</dc:creator>
<dc:creator>Tu, Y.</dc:creator>
<dc:creator>Kandasamy, A.</dc:creator>
<dc:creator>del Alamo, J. C.</dc:creator>
<dc:creator>Criado Hidalgo, E.</dc:creator>
<dc:date>2023-04-03</dc:date>
<dc:identifier>doi:10.1101/2023.03.31.535168</dc:identifier>
<dc:title><![CDATA[Tunable photoinitiated hydrogel microspheres for direct quantification of cell-generated forces in complex three-dimensional environments]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-04-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.04.14.536936v1?rss=1">
<title>
<![CDATA[
SUMOylation of Bonus, the Drosophila homolog of Transcription Intermediary Factor 1, safeguards germline identity by recruiting repressive chromatin complexes to silence tissue-specific genes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.04.14.536936v1?rss=1</link>
<description><![CDATA[
The conserved family of Transcription Intermediary Factors (TIF1) proteins consists of key transcriptional regulators that control transcription of target genes by modulating chromatin state. Unlike mammals that have four TIF1 members, Drosophila only encodes one member of the family, Bonus. Bonus has been implicated in embryonic development and organogenesis and shown to regulate several signaling pathways, however, its targets and mechanism of action remained poorly understood. We found that knockdown of Bonus in early oogenesis results in severe defects in ovarian development and in ectopic expression of genes that are normally repressed in the germline, demonstrating its essential function in the ovary. Recruitment of Bonus to chromatin leads to silencing associated with accumulation of the repressive H3K9me3 mark. We show that Bonus associates with the histone methyltransferase SetDB1 and the chromatin remodeler NuRD and depletion of either component releases Bonus-induced repression. We further established that Bonus is SUMOylated at a single site at its N-terminus that is conserved among insects and this modification is indispensable for Bonuss repressive activity. SUMOylation influences Bonuss subnuclear localization, its association with chromatin and interaction with SetDB1. Finally, we showed that Bonus SUMOylation is mediated by the SUMO E3-ligase Su(var)2-10, revealing that although SUMOylation of TIF1 proteins is conserved between insects and mammals, both the mechanism and specific site of modification is different in the two taxa. Together, our work identified Bonus as a regulator of tissue-specific gene expression and revealed the importance of SUMOylation as a regulator of complex formation in the context of transcriptional repression.
]]></description>
<dc:creator>Godneeva, B.</dc:creator>
<dc:creator>Ninova, M.</dc:creator>
<dc:creator>Fejes Toth, K.</dc:creator>
<dc:creator>Aravin, A.</dc:creator>
<dc:date>2023-04-15</dc:date>
<dc:identifier>doi:10.1101/2023.04.14.536936</dc:identifier>
<dc:title><![CDATA[SUMOylation of Bonus, the Drosophila homolog of Transcription Intermediary Factor 1, safeguards germline identity by recruiting repressive chromatin complexes to silence tissue-specific genes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-04-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.07.539389v1?rss=1">
<title>
<![CDATA[
Integrative mapping of spatial transcriptomic and amyloid pathology in Alzheimer's disease at single-cell resolution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.07.539389v1?rss=1</link>
<description><![CDATA[
Alzheimers disease (AD) is a complex neurodegenerative disorder that affects millions of people worldwide. Despite decades of research, the underlying molecular and cellular changes of AD remain unresolved, especially in terms of the spatial structure of gene expression changes that correlates with pathology, e.g. amyloid beta (A-beta) plaques. Recent advances in imaging-or sequencing-based single-cell spatial transcriptomics have allowed a systematic dissection of molecular and cell architectures in the brain and other tissues. In this study, we employed the recently developed Stereo-seq technology to spatially profile the whole-genome transcriptomics in the 5xFAD mouse model and established the methodology to analyze the specific neuronal transcriptomic changes spatially correlated with amyloid pathology at single cell resolution. More specifically, we developed a pipeline for integrative image- and non-image-based cell segmentation, VoxelMorph-based non-linear alignment, and Unet-based object detection to achieve reliable transcriptomics analysis at the single-cell resolution, and investigated the spatial relationship between diverse neuronal clusters and A-beta depositions. This work has demonstrated the potential of using the Stereo-seq technology as a powerful tool to investigate AD and other complex neurological disorders.
]]></description>
<dc:creator>Zhang, G.-W.</dc:creator>
<dc:creator>Xia, S.</dc:creator>
<dc:creator>Zhang, N. K.</dc:creator>
<dc:creator>Gao, F.</dc:creator>
<dc:creator>Zlokovic, B. V.</dc:creator>
<dc:creator>Zhang, L. I.</dc:creator>
<dc:creator>Zhao, Z.</dc:creator>
<dc:creator>Tao, H.</dc:creator>
<dc:date>2023-05-07</dc:date>
<dc:identifier>doi:10.1101/2023.05.07.539389</dc:identifier>
<dc:title><![CDATA[Integrative mapping of spatial transcriptomic and amyloid pathology in Alzheimer's disease at single-cell resolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.21.541598v1?rss=1">
<title>
<![CDATA[
Frequency- and circuit- specific effects of septohippocampal deep brain stimulation in mice as measured by functional ultrasound imaging. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.21.541598v1?rss=1</link>
<description><![CDATA[
BackgroundDeep brain stimulation (DBS) has shown remarkable success in treating neurological and psychiatric disorders such as Parkinsons disease, dystonia, epilepsy, and obsessive-compulsive disorder. Despite this success, the underlying mechanism of action remains unknown. DBS is now being explored to improve functional outcomes in other psychiatric conditions, such as those characterized by reduced N-methyl-D-aspartate (NMDA) function (i.e. schizophrenia). While DBS for movement disorders requires high-frequency continuous stimulation, there is evidence that intermittent low-frequency stimulation in neuropsychiatric conditions may have persisting cognitive benefits, necessitating a broader exploration of how DBS alters brain networks.

ObjectiveWe characterize the effects of pharmacologic NMDA antagonism on the septohippocampal network and the impact of high- and low-frequency MSN DBS on cerebral blood volume (CBV) in brain structures within and outside of the septohippocampal network.

MethodsIn this study, we utilize a novel technology, functional ultrasound imaging (fUSI), to characterize the cerebrovascular impact of medial septal nucleus (MSN) DBS under conditions of NMDA antagonism (pharmacologically using Dizocilpine [MK-801]) in anesthetized male mice.

ResultsImaging from a sagittal plane across a variety of brain regions, we find that MSN theta-frequency (7.7Hz) DBS has a larger effect on hippocampal CBV after stimulation offset. This is observed following an intraperitoneal (i.p.) injection of either saline vehicle or MK-801 (1 mg/kg). This effect is not present using standard high-frequency DBS stimulation parameters (i.e. gamma [100Hz]).

ConclusionThese results indicate the MSN DBS increases circuit-specific hippocampal neurovascular activity in a frequency-dependent manner that continues beyond the period of electrical stimulation.
]]></description>
<dc:creator>Crown, L. M.</dc:creator>
<dc:creator>Agyeman, K.</dc:creator>
<dc:creator>Choi, W.</dc:creator>
<dc:creator>Zepeda, N.</dc:creator>
<dc:creator>Siegel, S.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Christopoulos, V.</dc:creator>
<dc:creator>Lee, D.</dc:creator>
<dc:date>2023-05-22</dc:date>
<dc:identifier>doi:10.1101/2023.05.21.541598</dc:identifier>
<dc:title><![CDATA[Frequency- and circuit- specific effects of septohippocampal deep brain stimulation in mice as measured by functional ultrasound imaging.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.30.542725v1?rss=1">
<title>
<![CDATA[
Synaptic architecture of leg and wing motor control networks in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.30.542725v1?rss=1</link>
<description><![CDATA[
Animal movement is controlled by motor neurons (MNs), which project out of the central nervous system to activate muscles. MN activity is coordinated by complex premotor networks that allow individual muscles to contribute to many different behaviors. Here, we use connectomics to analyze the wiring logic of premotor circuits controlling the Drosophila leg and wing. We find that both premotor networks cluster into modules that link MNs innervating muscles with related functions. Within most leg motor modules, the synaptic weights of each premotor neuron are proportional to the size of their target MNs, establishing a circuit basis for hierarchical MN recruitment. In contrast, wing premotor networks lack proportional synaptic connectivity, which may allow wing steering muscles to be recruited with different relative timing. By comparing the architecture of distinct limb motor control systems within the same animal, we identify common principles of premotor network organization and specializations that reflect the unique biomechanical constraints and evolutionary origins of leg and wing motor control.
]]></description>
<dc:creator>Lesser, E.</dc:creator>
<dc:creator>Azevedo, A. W.</dc:creator>
<dc:creator>Phelps, J. S.</dc:creator>
<dc:creator>Elabbady, L.</dc:creator>
<dc:creator>Cook, A. P.</dc:creator>
<dc:creator>Mark, B.</dc:creator>
<dc:creator>Kuroda, S.</dc:creator>
<dc:creator>Sustar, A.</dc:creator>
<dc:creator>Moussa, A. J.</dc:creator>
<dc:creator>Dallmann, C. J.</dc:creator>
<dc:creator>Agrawal, S.</dc:creator>
<dc:creator>Lee, S.-Y. J.</dc:creator>
<dc:creator>Pratt, B. G.</dc:creator>
<dc:creator>Skutt-Kakari, K.</dc:creator>
<dc:creator>Gerhard, S.</dc:creator>
<dc:creator>Lu, R.</dc:creator>
<dc:creator>Kemnitz, N.</dc:creator>
<dc:creator>Lee, K.</dc:creator>
<dc:creator>Halageri, A.</dc:creator>
<dc:creator>Castro, M.</dc:creator>
<dc:creator>Ih, D.</dc:creator>
<dc:creator>Gager, J.</dc:creator>
<dc:creator>Tammam, M.</dc:creator>
<dc:creator>Dorkenwald, S.</dc:creator>
<dc:creator>Collman, F. C.</dc:creator>
<dc:creator>Schneider-Mizell, C. M.</dc:creator>
<dc:creator>Brittain, D.</dc:creator>
<dc:creator>Jordan, C. S.</dc:creator>
<dc:creator>Seung, H. S.</dc:creator>
<dc:creator>Macrina, T.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:creator>Lee, W.-C. A.</dc:creator>
<dc:creator>Tuthill, J. C.</dc:creator>
<dc:date>2023-05-31</dc:date>
<dc:identifier>doi:10.1101/2023.05.30.542725</dc:identifier>
<dc:title><![CDATA[Synaptic architecture of leg and wing motor control networks in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.05.30.542875v1?rss=1">
<title>
<![CDATA[
Closed ecosystems extract energy through self-organized nutrient cycles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.05.30.542875v1?rss=1</link>
<description><![CDATA[
Our planet is a self-sustaining ecosystem powered by light energy from the sun, but roughly closed to matter. Many ecosystems on Earth are also approximately closed to matter and recycle nutrients by self-organizing stable nutrient cycles, e.g., microbial mats, lakes, open ocean gyres. However, existing ecological models do not exhibit the self-organization and dynamical stability widely observed in such planetary-scale ecosystems. Here, we advance a new conceptual model that explains the self-organization, stability and emergent features of closed microbial ecosystems. Our model incorporates the bioenergetics of metabolism into an ecological framework. By studying this model, we uncover a crucial thermodynamic feedback loop that enables metabolically diverse communities to almost always stabilize nutrient cycles. Surprisingly, highly diverse communities self-organize to extract{approx} 10% of the maximum extractable energy, or{approx} 100 fold more than randomized communities. Further, with increasing diversity, distinct ecosystems show strongly correlated fluxes through nutrient cycles. However, as the driving force from light increases, the fluxes of nutrient cycles become more variable and species-dependent. Our results highlight that self-organization promotes the efficiency and stability of complex ecosystems at extracting energy from the environment, even in the absence of any centralized coordination.
]]></description>
<dc:creator>Goyal, A.</dc:creator>
<dc:creator>Flamholz, A. I.</dc:creator>
<dc:creator>Petroff, A. P.</dc:creator>
<dc:creator>Murugan, A.</dc:creator>
<dc:date>2023-06-01</dc:date>
<dc:identifier>doi:10.1101/2023.05.30.542875</dc:identifier>
<dc:title><![CDATA[Closed ecosystems extract energy through self-organized nutrient cycles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/204180v1?rss=1">
<title>
<![CDATA[
Cellular reprogramming of human monocytes is regulated by time-dependent IL4 signalling and NCOR2 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/204180v1?rss=1</link>
<description><![CDATA[
The clinical and therapeutic value of human in vitro generated monocyte-derived dendritic cell (moDC) and macrophages is well established. However, in line with recent findings regarding myeloid cell ontogeny and due to our limited understanding of their physiological counterparts, transcriptional regulation and heterogeneity, the full potential of these important cellular systems is still underestimated.nnIn this study, we use cutting edge high-dimensional analysis methods to better understand the transcriptional organization, phenotypic heterogeneity and functional differences between human ex vivo isolated and in vitro generated mononuclear phagocytes with the aim to better realize their full potential in the clinic.nnWe demonstrate that human monocytes activated by MCSF or GMCSF most closely resemble inflammatory macrophages identified in vivo, while IL4 signalling in the presence of GMCSF generates moDCs resembling inflammatory DCs in vivo, but not steady state cDC1 or cDC2. Moreover, these reprogramming regimes lead to activated monocytes that present with profoundly different transcriptomic, metabolic, phenotypic and functional profiles. Furthermore, we demonstrate that CD14+ monocytes are integrating multiple exogenous activation signals such as GMCSF and IL4 in a combinatorial and temporal fashion, resulting in a high-dimensional cellular continuum of reprogrammed monocytes dependent on the mode and timing of cytokine exposure. Utilizing nanostraw-based knockdown technology, we demonstrate that the IL4-dependent generation of moDCs relies on the induction, nuclear localization and function of the transcriptional regulator NCOR2.nnFinally, we unravel unappreciated heterogeneity within the clinically moDCs population and propose a novel high-dimensional phenotyping strategy to better tailor clinical quality control strategies for patient need and culture conditions to enhance therapeutic outcome.
]]></description>
<dc:creator>Sander, J.</dc:creator>
<dc:creator>Schmidt, S. V.</dc:creator>
<dc:creator>Cirovic, B.</dc:creator>
<dc:creator>McGovern, N.</dc:creator>
<dc:creator>Papantonopoulou, O.</dc:creator>
<dc:creator>Hardt, A.-L.</dc:creator>
<dc:creator>Aschenbrenner, A.</dc:creator>
<dc:creator>Kreer, C.</dc:creator>
<dc:creator>Quast, T.</dc:creator>
<dc:creator>Xu, A. M.</dc:creator>
<dc:creator>Schmidtleithner, L. M.</dc:creator>
<dc:creator>Theis, H.</dc:creator>
<dc:creator>Do, T. H. L.</dc:creator>
<dc:creator>Bin Sumatoh, H. R.</dc:creator>
<dc:creator>Lauterbach, M. A. R.</dc:creator>
<dc:creator>Schulte-Schrepping, J.</dc:creator>
<dc:creator>Guenther, P.</dc:creator>
<dc:creator>Xue, J.</dc:creator>
<dc:creator>Bassler, K.</dc:creator>
<dc:creator>Ulas, T.</dc:creator>
<dc:creator>Klee, K.</dc:creator>
<dc:creator>Herresthal, S.</dc:creator>
<dc:creator>Krebs, W.</dc:creator>
<dc:creator>Martin, B.</dc:creator>
<dc:creator>Latz, E.</dc:creator>
<dc:creator>Haendler, K.</dc:creator>
<dc:creator>Kraut, M.</dc:creator>
<dc:creator>Kolanus, W.</dc:creator>
<dc:creator>Beyer, M.</dc:creator>
<dc:creator>Falk, C. S.</dc:creator>
<dc:creator>Wiegmann, B.</dc:creator>
<dc:creator>Burgdorf, S.</dc:creator>
<dc:creator>Melosh, N. A.</dc:creator>
<dc:creator>Newell, E. W.</dc:creator>
<dc:creator>Ginhoux, F.</dc:creator>
<dc:creator>Schlitzer, A.</dc:creator>
<dc:creator>Schultze, J. L.</dc:creator>
<dc:date>2017-10-16</dc:date>
<dc:identifier>doi:10.1101/204180</dc:identifier>
<dc:title><![CDATA[Cellular reprogramming of human monocytes is regulated by time-dependent IL4 signalling and NCOR2]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/210724v1?rss=1">
<title>
<![CDATA[
A study of allelic series using transcriptomic phenotypes in a metazoan 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/210724v1?rss=1</link>
<description><![CDATA[
Although transcriptomes have recently been used to perform epistasis analyses, they are not yet used to study intragenic function/structure relationships. We developed a theoretical framework to study allelic series using transcriptomic phenotypes. As a proof-of-concept, we apply our methods to an allelic series of dpy-22, a highly pleiotropic Caenorhabditis elegans gene orthologous to the human gene MED12, which is a subunit of the Mediator complex. Our methods identify functional regions within dpy-22 that modulate Mediator activity upon various genetic modules.
]]></description>
<dc:creator>Angeles-Albores, D.</dc:creator>
<dc:creator>Sternberg, P.</dc:creator>
<dc:date>2017-10-29</dc:date>
<dc:identifier>doi:10.1101/210724</dc:identifier>
<dc:title><![CDATA[A study of allelic series using transcriptomic phenotypes in a metazoan]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/225045v1?rss=1">
<title>
<![CDATA[
Control of bacterial population density with population feedback and molecular sequestration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/225045v1?rss=1</link>
<description><![CDATA[
Genetic engineering technology has become sophisticated enough to allow precise manipulation of bacterial genetic material. Engineering efforts with these technologies have created modified bacteria for various medical, industrial, and environmental purposes, but organisms designed for specific functions require improvements in stability, longevity, or efficiency of function. Most bacteria live in multispecies communities, whose composition may be closely linked to the effect the community has on the environment. Bacterial engineering efforts will benefit from building communities with regulated compositions, which will enable more stable and powerful community functions.nnWe present a design of a synthetic two member bacterial community capable of maintaining its composition at a defined ratio of [cell type 1]: [cell type 2]. We have constructed the genetic motif that will act in each cell in the two member community, containing an AHL-based negative feedback loop that activates ccdB toxin, which caps population density with increasing feedback strength. It also contains one of two ccdB sequestration modules, either the ccdA protein antitoxin, or an RNA device which prevents transcription and translation of ccdB mRNA, that rescues capped population density with induction. We compare absorbance and colony counting methods of estimating bacterial population density, finding that absorbance-based methods overestimate viable population density when ccdB toxin is used to control population density.nnPrior modeling results show that two cell types containing this genetic circuit motif that reciprocally activate the others ccdB sequestration device will establish a steady state ratio of cell types. Experimental testing and tuning the full two member community will help us improve our modeling of multi-member bacterial communities, learn more about the strengths and weaknesses of our design for community composition control, and identify general principles of design of compositionally-regulated microbial communities.
]]></description>
<dc:creator>McCardell, R. D.</dc:creator>
<dc:creator>Huang, S.</dc:creator>
<dc:creator>Green, L. N.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2017-11-25</dc:date>
<dc:identifier>doi:10.1101/225045</dc:identifier>
<dc:title><![CDATA[Control of bacterial population density with population feedback and molecular sequestration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/240747v1?rss=1">
<title>
<![CDATA[
Improved Aedes aegypti mosquito reference genome assembly enables biological discovery and vector control 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/240747v1?rss=1</link>
<description><![CDATA[
Female Aedes aegypti mosquitoes infect hundreds of millions of people each year with dangerous viral pathogens including dengue, yellow fever, Zika, and chikungunya. Progress in understanding the biology of this insect, and developing tools to fight it, has been slowed by the lack of a high-quality genome assembly. Here we combine diverse genome technologies to produce AaegL5, a dramatically improved and annotated assembly, and demonstrate how it accelerates mosquito science and control. We anchored the physical and cytogenetic maps, resolved the size and composition of the elusive sex-determining "M locus", significantly increased the known members of the glutathione-S-transferase genes important for insecticide resistance, and doubled the number of chemosensory ionotropic receptors that guide mosquitoes to human hosts and egg-laying sites. Using high-resolution QTL and population genomic analyses, we mapped new candidates for dengue vector competence and insecticide resistance. We predict that AaegL5 will catalyse new biological insights and intervention strategies to fight this deadly arboviral vector.
]]></description>
<dc:creator>Matthews, B. J.</dc:creator>
<dc:creator>Dudchenko, O.</dc:creator>
<dc:creator>Kingan, S.</dc:creator>
<dc:creator>Koren, S.</dc:creator>
<dc:creator>Antoshechkin, I.</dc:creator>
<dc:creator>Crawford, J. E.</dc:creator>
<dc:creator>Glassford, W. J.</dc:creator>
<dc:creator>Herre, M.</dc:creator>
<dc:creator>Redmond, S. N.</dc:creator>
<dc:creator>Rose, N. H.</dc:creator>
<dc:creator>Weedall, G. D.</dc:creator>
<dc:creator>Wu, Y.</dc:creator>
<dc:creator>Batra, S. S.</dc:creator>
<dc:creator>Brito-Sierra, C. A.</dc:creator>
<dc:creator>Buckingham, S. D.</dc:creator>
<dc:creator>Campbell, C. L.</dc:creator>
<dc:creator>Chan, S.</dc:creator>
<dc:creator>Cox, E.</dc:creator>
<dc:creator>Evans, B. R.</dc:creator>
<dc:creator>Fansiri, T.</dc:creator>
<dc:creator>Filipovic, I.</dc:creator>
<dc:creator>Fontaine, A.</dc:creator>
<dc:creator>Gloria-Soria, A.</dc:creator>
<dc:creator>Hall, R.</dc:creator>
<dc:creator>Joardar, V. S.</dc:creator>
<dc:creator>Jones, A. K.</dc:creator>
<dc:creator>Kay, R. G. G.</dc:creator>
<dc:creator>Kodali, V.</dc:creator>
<dc:creator>Lee, J.</dc:creator>
<dc:creator>Lycett, G. J.</dc:creator>
<dc:creator>Mitchell, S. N.</dc:creator>
<dc:creator>Muehling, J.</dc:creator>
<dc:creator>Murphy, M. R.</dc:creator>
<dc:creator>Omer, A.</dc:creator>
<dc:creator>Partridge, F. A.</dc:creator>
<dc:creator>Peluso, P.</dc:creator>
<dc:creator>Aiden, A. P.</dc:creator>
<dc:creator>Ramasamy, V.</dc:creator>
<dc:creator>Rasic, G.</dc:creator>
<dc:creator>Roy, S.</dc:creator>
<dc:creator>Saavedra-Rodriguez, K.</dc:creator>
<dc:creator>Sharan, S.</dc:creator>
<dc:creator>Sha</dc:creator>
<dc:date>2017-12-29</dc:date>
<dc:identifier>doi:10.1101/240747</dc:identifier>
<dc:title><![CDATA[Improved Aedes aegypti mosquito reference genome assembly enables biological discovery and vector control]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-12-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/272468v1?rss=1">
<title>
<![CDATA[
VideoTagger: User-Friendly Software for Annotating Video Experiments of Any Duration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/272468v1?rss=1</link>
<description><![CDATA[
BackgroundScientific insight is often sought by recording and analyzing large quantities of video. While easy access to cameras has increased the quantity of collected videos, the rate at which they can be analyzed remains a major limitation. Often, bench scientists struggle with the most basic problem that there is currently no user-friendly, flexible, and open source software tool with which to watch and annotate these videos.nnResultsWe have created the VideoTagger tool to address these and many of the other associated challenges of video analysis. VideoTagger allows non-programming users to efficiently explore, annotate, and visualize large quantities of video data, within their existing experimental protocols. Further, it is built to accept programmed plugins written in Python, to enable seamless integration with other sophisticated computer-aided analyses.nnWe tested VideoTagger ourselves, and have a growing base of users in other scientific disciplines. Capitalising on the unique features of VideoTagger to play back infinite lengths of video footage at various speeds, we annotated 39h of a Drosophila melanogaster lifespan video, at approximately 10-15x faster than real-time. We then used these labels to train a machine-learning plugin, which we used to annotate an additional 538h of footage automatically. In this way, we found that flies fall over spontaneously with increasing frequency as they age, and also spend longer durations struggling to right themselves. Ageing in flies is typically defined by length of life. We propose that this new mobility measure of ageing could help the discovery of mechanisms in biogerontology, refining our definition of what healthy ageing means in this extremely small, but widely used, invertebrate.nnConclusionsWe show how VideoTagger is sufficiently flexible for studying lengthy and/or numerous video experiments, thus directly improving scientists productivity across varied domains.
]]></description>
<dc:creator>Rennert, P.</dc:creator>
<dc:creator>Mac Aodha, O.</dc:creator>
<dc:creator>Piper, M.</dc:creator>
<dc:creator>Brostow, G.</dc:creator>
<dc:date>2018-02-27</dc:date>
<dc:identifier>doi:10.1101/272468</dc:identifier>
<dc:title><![CDATA[VideoTagger: User-Friendly Software for Annotating Video Experiments of Any Duration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-02-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/281360v1?rss=1">
<title>
<![CDATA[
Evolutionary analysis implicates RNA polymerase II pausing and chromatin structure in nematode piRNA biogenesis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/281360v1?rss=1</link>
<description><![CDATA[
Piwi-interacting RNAs (piRNAs) control transposable elements widely across metazoans but have rapidly evolving biogenesis pathways. In Caenorhabditis elegans, almost all piRNA loci are found within two 3Mb clusters on Chromosome IV. Each piRNA locus possesses an upstream motif that recruits RNA polymerase II to produce a [~]28 nt precursor transcript. Here, we use comparative epigenomics across nematodes to gain insight into piRNA biogenesis. We show that the piRNA upstream motif is derived from core promoter elements controlling snRNA biogenesis. We describe two alternative modes of piRNA organisation in nematodes: in C. elegans and closely related nematodes, piRNAs are clustered within repressive H3K27me3 chromatin, whilst in other species, typified by Pristionchus pacificus, piRNAs are distributed genome-wide within introns of actively transcribed genes. In both groups, piRNA production depends on downstream sequence signals associated with RNA polymerase II pausing, which synergise with the chromatin environment to control piRNA precursor transcription.
]]></description>
<dc:creator>Beltran, T.</dc:creator>
<dc:creator>Barruso, C.</dc:creator>
<dc:creator>Birkle, T.</dc:creator>
<dc:creator>Stevens, L.</dc:creator>
<dc:creator>Schwartz, H. T.</dc:creator>
<dc:creator>Sternberg, P.</dc:creator>
<dc:creator>Fradin, H.</dc:creator>
<dc:creator>Gunsalus, K.</dc:creator>
<dc:creator>Piano, F.</dc:creator>
<dc:creator>Martinez-Perez, E.</dc:creator>
<dc:creator>Blaxter, M.</dc:creator>
<dc:creator>Sarkies, P.</dc:creator>
<dc:date>2018-03-13</dc:date>
<dc:identifier>doi:10.1101/281360</dc:identifier>
<dc:title><![CDATA[Evolutionary analysis implicates RNA polymerase II pausing and chromatin structure in nematode piRNA biogenesis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/289546v1?rss=1">
<title>
<![CDATA[
Behavior of homing endonuclease gene drives targeting genes required for viability or female fertility with multiplexed guide RNAs 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/289546v1?rss=1</link>
<description><![CDATA[
A gene drive method of particular interest for population suppression utilizes homing endonuclease genes (HEGs), wherein a site-specific nuclease-encoding cassette is copied, in the germline, into a target gene whose loss of function results in loss of viability or fertility in homozygous, but not heterozygous progeny. Earlier work in Drosophila and mosquitoes utilized HEGs consisting of Cas9 and a single gRNA that together target a specific gene for cleavage. Homing was observed, but resistant alleles, immune to cleavage, while retaining wildtype gene function, were also created through non-homologous end joining. Such alleles prevent drive and population suppression. Targeting a gene for cleavage at multiple positions has been suggested as a strategy to prevent the appearance of resistant alleles. To test this hypothesis, we generated two suppression HEGs, targeting genes required for embryonic viability or fertility, using a HEG consisting of CRISPR/Cas9 and guide RNAs (gRNAs) designed to cleave each gene at four positions. Rates of target locus cleavage were very high, and multiplexing of gRNAs prevented resistant allele formation. However, germline homing rates were modest, and the HEG cassette was unstable during homing events, resulting in frequent partial copying of HEGs that lacked gRNAs, a dominant marker gene, or Cas9. Finally, in drive experiments the HEGs failed to spread, due to the high fitness load induced in offspring as a result of maternal carry over of Cas9/gRNA complex activity. Alternative design principles are proposed that may mitigate these problems in future gene drive engineering.nnSignificance statementHEG-based gene drive can bring about population suppression when genes required for viability or fertility are targeted. However, these strategies are vulnerable to failure through mechanisms that create alleles resistant to cleavage, but that retain wildtype gene function. We show that resistance allele creation can be prevented through the use of gRNAs designed to cleave a gene at four target sites. However, homing rates were modest, and the HEGs were unstable during homing. In addition, use of a promoter active in the female germline resulted in levels of HEG carryover that compromised the viability or fertility of HEG-bearing heterozygotes, thereby preventing drive. We propose strategies that can help to overcome these problems in next generation HEG systems.
]]></description>
<dc:creator>Oberhofer, G.</dc:creator>
<dc:creator>Ivy, T.</dc:creator>
<dc:creator>Hay, B. A.</dc:creator>
<dc:date>2018-03-27</dc:date>
<dc:identifier>doi:10.1101/289546</dc:identifier>
<dc:title><![CDATA[Behavior of homing endonuclease gene drives targeting genes required for viability or female fertility with multiplexed guide RNAs]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/321265v1?rss=1">
<title>
<![CDATA[
Augmented Reality Powers a Cognitive Prosthesis for the Blind 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/321265v1?rss=1</link>
<description><![CDATA[
To restore vision for the blind several prosthetic approaches have been explored that convey raw images to the brain. So far these schemes all suffer from a lack of bandwidth and the extensive training required to interpret unusual stimuli. Here we present an alternate approach that restores vision at the cognitive level, bypassing the need to convey sensory data. A wearable computer captures video and other data, extracts the important scene knowledge, and conveys that through auditory augmented reality. This system supports many aspects of visual cognition: from obstacle avoidance to formation and recall of spatial memories, to long-range navigation. Neither training nor modification of the physical environment are required: Blind subjects can navigate an unfamiliar multi-story building on their first attempt. The combination of unprecedented computing power in wearable devices with augmented reality technology promises a new era of non-invasive prostheses that are limited only by software.nnImpact StatementA non-invasive prosthesis for blind people endows objects in the environment with voices, allowing a user to explore the scene, localize objects, and navigate through a building with minimal training.
]]></description>
<dc:creator>Liu, Y.</dc:creator>
<dc:creator>Stiles, N. R. B.</dc:creator>
<dc:creator>Meister, M.</dc:creator>
<dc:date>2018-05-22</dc:date>
<dc:identifier>doi:10.1101/321265</dc:identifier>
<dc:title><![CDATA[Augmented Reality Powers a Cognitive Prosthesis for the Blind]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/321307v1?rss=1">
<title>
<![CDATA[
Long-distance communication in synthetic bacterial consortia through active signal propagation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/321307v1?rss=1</link>
<description><![CDATA[
A synthetic cell-cell signaling circuit should ideally be (1) metabolically lightweight, (2) insulated from endogenous gene networks, and (3) excitable rather than oscillatory or bistable. To accomplish these three features, we propose a synchronized pulse-generating circuit based on the design of published synchronized oscillators. This communication module employs a pulse generator built using Lux-type quorum sensing components and an IFFL transcriptional circuit. Both the input and output of this module are AHLs, the quorum sensing signaling molecule. Cells bearing this module therefore act as an excitable medium, producing a pulse of AHL when stimulated by exogenous AHL. Using simulation and microscopy, we demonstrate how this circuit enables traveling pulses of AHL production through microcolonies growing in two dimensions. Traveling pulses achieve cell-cell communication at longer distances than can be achieved by diffusion of signal from sender to receiver cells and may permit more sophisticated coordination in synthetic consortia.
]]></description>
<dc:creator>Parkin, J. M.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2018-05-14</dc:date>
<dc:identifier>doi:10.1101/321307</dc:identifier>
<dc:title><![CDATA[Long-distance communication in synthetic bacterial consortia through active signal propagation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/334656v1?rss=1">
<title>
<![CDATA[
Genetic, biochemical, and molecular characterization of Methanosarcina barkeri mutants lacking three distinct classes of hydrogenase 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/334656v1?rss=1</link>
<description><![CDATA[
The methanogenic archaeon Methanosarcina barkeri encodes three distinct types of hydrogenase, whose functions vary depending on the growth substrate. These include the F420-dependent (Frh), methanophenazine-dependent (Vht), and ferredoxin-dependent (Ech) hydrogenases. To investigate their physiological roles, we characterized a series of mutants lacking each hydrogenase in various combinations. Mutants lacking Frh, Vht, or Ech in any combination failed to grow on H2/CO2, whereas only Vht and Ech were essential for growth on acetate. In contrast, a mutant lacking all three grew on methanol with a final growth yield similar to wild-type, produced methane and CO2 in the expected 3:1 ratio, but had a ca. 33% slower growth rate. Thus, hydrogenases play a significant, but non-essential, role during growth on this substrate. As previously observed, mutants lacking Ech fail to grow on methanol/H2 unless supplemented with biosynthetic precursors. Interestingly, this phenotype was abolished in the {Delta}ech/{Delta}frh and {Delta}ech/{Delta}frh/{Delta}vht mutants, consistent with the idea that hydrogenases inhibit methanol oxidation in the presence of H2, which prevents production of reducing equivalents needed for biosynthesis. Quantification of methane and CO2 produced from methanol by resting cell suspensions of various mutants supports this conclusion. Based on global transcriptional profiles, none of the hydrogenases are upregulated to compensate for loss of the others. However, transcript levels of the F420 dehydrogenase operon were significantly higher in all strains lacking frh, suggesting a mechanism to sense the redox state of F420. The roles of the hydrogenases in energy conservation during growth with each methanogenic pathway are discussed.
]]></description>
<dc:creator>Kulkarni, G.</dc:creator>
<dc:creator>Mand, T. D.</dc:creator>
<dc:creator>Metcalf, W. W.</dc:creator>
<dc:date>2018-05-30</dc:date>
<dc:identifier>doi:10.1101/334656</dc:identifier>
<dc:title><![CDATA[Genetic, biochemical, and molecular characterization of Methanosarcina barkeri mutants lacking three distinct classes of hydrogenase]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/335794v1?rss=1">
<title>
<![CDATA[
Energy conservation via hydrogen cycling in the methanogenic archaeon Methanosarcina barkeri 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/335794v1?rss=1</link>
<description><![CDATA[
Energy conservation via hydrogen cycling, which generates proton motive force by intracellular H2 production coupled to extracellular consumption, has been controversial since it was first proposed in 1981. It was hypothesized that the methanogenic archaeon Methanosarcina barkeri is capable of energy conservation via H2 cycling, based on genetic data that suggest H2 is a preferred, but non-essential, intermediate in the electron transport chain of this organism. Here, we characterize a series of hydrogenase mutants to provide direct evidence of H2 cycling. M. barkeri produces H2 during growth on methanol, a phenotype that is lost upon mutation of the cytoplasmic hydrogenase encoded by frhADGB, although low levels of H2, attributable to the Ech hydrogenase, accumulate during stationary phase. In contrast, mutations that conditionally inactivate the extracellular Vht hydrogenase are lethal when expression of the vhtGACD operon is repressed. Under these conditions H2 accumulates, with concomitant cessation of methane production and subsequent cell lysis, suggesting that the inability to recapture extracellular H2 is responsible for the lethal phenotype. Consistent with this interpretation, double mutants that lack both Vht and Frh are viable. Thus, when intracellular hydrogen production is abrogated, loss of extracellular H2 consumption is no longer lethal. The common occurrence of both intracellular and extracellular hydrogenases in anaerobic microorganisms suggests that this unusual mechanism of energy conservation may be widespread in nature.nnImportanceAdenosine triphosphate (ATP) is required by all living organisms to facilitate essential endergonic reactions required for growth and maintenance. Although synthesis of ATP by substrate-level phosphorylation is widespread and significant, most ATP is made via the enzyme ATP synthase, which is energized by transmembrane chemiosmotic gradients. Therefore, establishing this gradient across the membrane is of central importance to sustaining life. Experimental validation of H2 cycling adds to a short list of mechanisms for generating a transmembrane electrochemical gradient that is likely to be widespread, especially among anaerobic microorganisms.
]]></description>
<dc:creator>Kulkarni, G.</dc:creator>
<dc:creator>Mand, T. D.</dc:creator>
<dc:creator>Metcalf, W. W.</dc:creator>
<dc:date>2018-05-31</dc:date>
<dc:identifier>doi:10.1101/335794</dc:identifier>
<dc:title><![CDATA[Energy conservation via hydrogen cycling in the methanogenic archaeon Methanosarcina barkeri]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-05-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/338178v1?rss=1">
<title>
<![CDATA[
Single-cell transcriptomics identifies CD44 as a new marker and regulator of haematopoietic stem cells development 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/338178v1?rss=1</link>
<description><![CDATA[
The endothelial to haematopoietic transition (EHT) is the process whereby haemogenic endothelium differentiates into haematopoietic stem and progenitor cells (HSPCs). The intermediary steps of this process are unclear, in particular the identity of endothelial cells that give rise to HSPCs is unknown. Using single-cell transcriptome analysis and antibody screening we identified CD44 as a new marker of EHT enabling us to isolate robustly the different stages of EHT in the aorta gonad mesonephros (AGM) region. This allowed us to provide a very detailed phenotypical and transcriptional profile for haemogenic endothelial cells, characterising them with high expression of genes related to Notch signalling, TGFbeta/BMP antagonists (Smad6, Smad7 and Bmper) and a downregulation of genes related to glycolysis and the TCA cycle. Moreover, we demonstrated that by inhibiting the interaction between CD44 and its ligand hyaluronan we could block EHT, identifying a new regulator of HSPC development.
]]></description>
<dc:creator>Oatley, M.</dc:creator>
<dc:creator>Vargel Bolukbasi, O.</dc:creator>
<dc:creator>Svensson, V.</dc:creator>
<dc:creator>Shvartsman, M.</dc:creator>
<dc:creator>Ganter, K.</dc:creator>
<dc:creator>Zirngibl, K.</dc:creator>
<dc:creator>Pavlovich, P. V.</dc:creator>
<dc:creator>Milchevskaya, V.</dc:creator>
<dc:creator>Foteva, V.</dc:creator>
<dc:creator>Natarajan, K. N.</dc:creator>
<dc:creator>Baying, B.</dc:creator>
<dc:creator>Benes, V.</dc:creator>
<dc:creator>Patil, K. R.</dc:creator>
<dc:creator>Teichmann, S. A.</dc:creator>
<dc:creator>Lancrin, C.</dc:creator>
<dc:date>2018-06-06</dc:date>
<dc:identifier>doi:10.1101/338178</dc:identifier>
<dc:title><![CDATA[Single-cell transcriptomics identifies CD44 as a new marker and regulator of haematopoietic stem cells development]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-06-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/339556v1?rss=1">
<title>
<![CDATA[
A command-like descending neuron that coordinately activates backward and inhibits forward locomotion 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/339556v1?rss=1</link>
<description><![CDATA[
Command-like descending neurons can induce many behaviors, such as backward locomotion, escape, feeding, courtship, egg-laying, or grooming. In most animals it remains unknown how neural circuits switch between these antagonistic behaviors: via top-down activation/inhibition of antagonistic circuits or via reciprocal inhibition between antagonistic circuits. Here we use genetic screens, intersectional genetics, circuit reconstruction by electron microscopy, and functional optogenetics to identify a bilateral pair of larval "mooncrawler descending neurons" (MDNs) with command-like ability to coordinately induce backward locomotion and block forward locomotion; the former by activating a backward-specific premotor neuron, and the latter by disynaptic inhibition of a forward-specific premotor neuron. In contrast, direct reciprocal inhibition between forward and backward circuits was not observed. Thus, MDNs coordinate a transition between antagonistic larval locomotor behaviors. Interestingly, larval MDNs persist into adulthood, where they can trigger backward walking. Thus, MDNs induce backward locomotion in both limbless and limbed animals.nnHighlightsO_LIMDN command-like descending neuron induces backward larval locomotionnC_LIO_LIMDN neurons coordinately regulate antagonistic behaviors (forward/backward locomotion)nC_LIO_LIMDN-motor circuit validated at structural (TEM) and functional (optogenetic) levelsnC_LIO_LIMDN neurons induce backward locomotion in both limbless larva and limbed adultnC_LI
]]></description>
<dc:creator>Doe, C. Q.</dc:creator>
<dc:creator>Zarin, A. A.</dc:creator>
<dc:creator>Carreira-Rosario, A.</dc:creator>
<dc:creator>Clark, M. Q.</dc:creator>
<dc:creator>Manning, L.</dc:creator>
<dc:creator>Cardona, A.</dc:creator>
<dc:creator>Fetter, R. D.</dc:creator>
<dc:date>2018-06-05</dc:date>
<dc:identifier>doi:10.1101/339556</dc:identifier>
<dc:title><![CDATA[A command-like descending neuron that coordinately activates backward and inhibits forward locomotion]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-06-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/343558v1?rss=1">
<title>
<![CDATA[
Multiple sclerosis-associated changes in the composition and immune functions of spore-forming bacteria 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/343558v1?rss=1</link>
<description><![CDATA[
Multiple sclerosis (MS) is an autoimmune disease of the central nervous system characterized by adaptive and innate immune system dysregulation. Recent work has revealed moderate alteration of gut microbial communities in subjects with MS and in experimental, induced models. However, a mechanistic understanding linking the observed changes in the microbiota and the presence of the disease is still missing. Chloroform-resistant, spore-forming bacteria have been shown to exhibit immunomodulatory properties in vitro and in vivo, but they have not yet been characterized in the context of human disease. This study addresses the community composition and immune function of this bacterial fraction in MS. We identify MS-associated spore-forming taxa and show that their presence correlates with impaired differentiation of IL-10 secreting, regulatory T lymphocytes in-vitro. Colonization of antibiotic-treated mice with spore-forming bacteria allowed us to identify some bacterial taxa favoring IL-10+ lymphocyte differentiation and others inducing differentiation of pro-inflammatory, IFN{gamma}+ T lymphocytes. However, when fed into antibiotic-treated mice, both MS and control derived spore-forming bacteria were able to induce immunoregulatory responses.nnOur analysis also identified Akkermansia muciniphila as a key organism that may interact either directly or indirectly with spore-forming bacteria to exacerbate the inflammatory effects of MS-associated gut microbiota. Thus, changes in the spore-forming fraction may influence T lymphocyte-mediated inflammation in MS. This experimental approach of isolating a subset of microbiota based on its functional characteristics may be useful to investigate other microbial fractions at greater depth.nnImportanceDespite the rapid emergence of microbiome related studies in human diseases, few go beyond a simple description of relative taxa levels in a select group of patients. Our study integrates computational analysis with in vitro and in vivo exploration of inflammatory properties of both complete microbial communities and individual taxa, revealing novel functional associations. We specifically show that while small differences exist between the microbiomes of MS patients and healthy subjects, these differences are exacerbated in the chloroform resistant fraction. We further demonstrate that, when purified from MS patients, this fraction is associated with impaired immunomodulatory responses in vitro.
]]></description>
<dc:creator>Cekanaviciute, E.</dc:creator>
<dc:creator>Probstel, A.-K.</dc:creator>
<dc:creator>Thomann, A.</dc:creator>
<dc:creator>Runia, T.</dc:creator>
<dc:creator>Casaccia, P.</dc:creator>
<dc:creator>Katz Sand, I.</dc:creator>
<dc:creator>Crabtree, E.</dc:creator>
<dc:creator>Singh, S.</dc:creator>
<dc:creator>Morrissey, J.</dc:creator>
<dc:creator>Barba, P.</dc:creator>
<dc:creator>Gomez, R.</dc:creator>
<dc:creator>Knight, R.</dc:creator>
<dc:creator>Mazmanian, S.</dc:creator>
<dc:creator>Graves, J.</dc:creator>
<dc:creator>Cree, B. C. A.</dc:creator>
<dc:creator>Zamvil, S. S.</dc:creator>
<dc:creator>Baranzini, S.</dc:creator>
<dc:date>2018-06-11</dc:date>
<dc:identifier>doi:10.1101/343558</dc:identifier>
<dc:title><![CDATA[Multiple sclerosis-associated changes in the composition and immune functions of spore-forming bacteria]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-06-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/360040v1?rss=1">
<title>
<![CDATA[
Context Dependence of Biological Circuits 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/360040v1?rss=1</link>
<description><![CDATA[
It has been an ongoing scientific debate whether biological parameters are conserved across experimental setups with different media, pH values, and other experimental conditions. Our work explores this question using Bayesian probability as a rigorous framework to assess the biological context of parameters in a model of the cell growth controller in You et al. When this growth controller is uninduced, the E. coli cell population grows to carrying capacity; however, when the circuit is induced, the cell population growth is regulated to remain well below carrying capacity. This growth control controller regulates the E. coli cell population by cell-cell communication using the signaling molecule AHL and by cell death using the bacterial toxin CcdB.nnTo evaluate the context dependence of parameters such as the cell growth rate, the carrying capacity, the AHL degradation rate, the leakiness of AHL, the leakiness of toxin CcdB, and the IPTG induction factor, we collect experimental data from the growth control circuit in two different media, at two different pH values, and with several induction levels. We define a set of possible context-dependencies that describe how these parameters may differ with the experimental conditions and we develop mathematical models of the growth controller across the different experimental contexts. We then determine whether these parameters are shared across experimental contexts or whether they are context-dependent. For each of these possible context-dependencies, we use Bayesian inference to assess its plausibility and to estimate the growth controllers parameters assuming this context-dependency. Ultimately, we find that there is significant experimental context-dependence in this circuit. Moreover, we also find that the estimated parameter values are sensitive to our assumption of a context relationship.
]]></description>
<dc:creator>Catanach, T.</dc:creator>
<dc:creator>McCardell, R. D.</dc:creator>
<dc:creator>Baetica, A.-A.</dc:creator>
<dc:creator>Murray, R.</dc:creator>
<dc:date>2018-07-03</dc:date>
<dc:identifier>doi:10.1101/360040</dc:identifier>
<dc:title><![CDATA[Context Dependence of Biological Circuits]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-07-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/380972v1?rss=1">
<title>
<![CDATA[
Precision measurement of cis-regulatory energetics in living cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/380972v1?rss=1</link>
<description><![CDATA[
Gene expression in all organisms is controlled by cooperative interactions between DNA-bound transcription factors (TFs), but quantitatively measuring TF-DNA and TF-TF interactions remains difficult. Here we introduce a strategy for precisely measuring the Gibbs free energy of such interactions in living cells. This strategy centers on the measurement and modeling of "allelic manifolds", a multidimensional generalization of the classical genetics concept of allelic series. Allelic manifolds are measured using reporter assays performed on strategically designed cis-regulatory sequences. Quantitative biophysical models are then fit to the resulting data. We used this strategy to study regulation by two Escherichia coli TFs, CRP and {sigma}70 RNA polymerase. Doing so, we consistently obtained energetic measurements precise to ~ 0.1 kcal/mol. We also obtained multiple results that deviate from the prior literature. Our strategy is compatible with massively parallel reporter assays in both prokaryotes and eukaryotes, and should therefore be highly scalable and broadly applicable.
]]></description>
<dc:creator>Forcier, T.</dc:creator>
<dc:creator>Ayaz, A.</dc:creator>
<dc:creator>Gill, M. S.</dc:creator>
<dc:creator>Jones, D.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:creator>Kinney, J. B.</dc:creator>
<dc:date>2018-07-31</dc:date>
<dc:identifier>doi:10.1101/380972</dc:identifier>
<dc:title><![CDATA[Precision measurement of cis-regulatory energetics in living cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-07-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/423905v1?rss=1">
<title>
<![CDATA[
Multiple C2 domains and Transmembrane region Proteins (MCTPs) tether membranes at plasmodesmata 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/423905v1?rss=1</link>
<description><![CDATA[
AO_SCPLOWBSTRACTC_SCPLOWIn eukaryotes, membrane contact sites (MCS) allow direct communication between organelles. Plants have evolved unique MCS, the plasmodesmata intercellular pores, which combine endoplasmic reticulum (ER) - plasma membrane (PM) contacts with regulation of cell-to-cell signalling. The molecular mechanism and function of membrane tethering within plasmodesmata remains unknown.nnHere we show that the Multiple C2 domains and Transmembrane region Protein (MCTP) family, key regulators of cell-to-cell signalling in plants, act as ER - PM tethers specifically at plasmodesmata. We report that MCTPs are core plasmodesmata proteins that insert into the ER via their transmembrane region whilst their C2 domains dock to the PM through interaction with anionic phospholipids. A mctp3/4 loss-of-function mutant induces plant developmental defects while MCTP4 expression in a yeast {Delta}tether mutant partially restores ER-PM tethering. Our data suggest that MCTPs are unique membrane tethers controlling both ER-PM contacts and cell-cell signalling.
]]></description>
<dc:creator>Brault, M. L.</dc:creator>
<dc:creator>Petit, J. D.</dc:creator>
<dc:creator>Immel, F.</dc:creator>
<dc:creator>Nicolas, W. J.</dc:creator>
<dc:creator>Brocard, L.</dc:creator>
<dc:creator>Gaston, A.</dc:creator>
<dc:creator>Fouche, M.</dc:creator>
<dc:creator>Hawkins, T. J.</dc:creator>
<dc:creator>Crowet, J.-M.</dc:creator>
<dc:creator>Grison, M. S.</dc:creator>
<dc:creator>Kraner, M.</dc:creator>
<dc:creator>Alva, V.</dc:creator>
<dc:creator>Claverol, S.</dc:creator>
<dc:creator>Deleu, M.</dc:creator>
<dc:creator>Lins, L.</dc:creator>
<dc:creator>Tilsner, J.</dc:creator>
<dc:creator>Bayer, E. E.</dc:creator>
<dc:date>2018-09-23</dc:date>
<dc:identifier>doi:10.1101/423905</dc:identifier>
<dc:title><![CDATA[Multiple C2 domains and Transmembrane region Proteins (MCTPs) tether membranes at plasmodesmata]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-09-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/433771v1?rss=1">
<title>
<![CDATA[
Diverse food-sensing neurons trigger idiothetic local search in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/433771v1?rss=1</link>
<description><![CDATA[
Resources are often sparsely clustered in nature. Thus, foraging animals may benefit from remembering the location of a newly discovered food patch while continuing to explore nearby [1, 2]. For example, after encountering a drop of yeast or sugar, hungry flies often perform a local search consisting of frequent departures and returns to the food site [3, 4]. Fruit flies, Drosophila melanogaster, can perform this food-centered search behavior in the absence of external stimuli or landmarks, instead relying solely on internal (idiothetic) cues to keep track of their location [5]. This path integration behavior may represent a deeply conserved navigational capacity in insects [6, 7], but the neural pathways underlying food-triggered searches remain unknown. Here, we used optogenetic activation to screen candidate cell classes and found that local searches can be initiated by diverse sensory neurons including sugar-sensors, water-sensors, olfactory-receptor neurons, as well as hunger-signaling neurons of the central nervous system. Optogenetically-induced searches resemble those triggered by actual food and are modulated by starvation state. Furthermore, search trajectories exhibit key features of path integration: searches remain tightly centered around the fictive-food site, even during long periods without reinforcement, and flies re-center their searches when they encounter a new fictive-food site. Flies can even perform elaborate local searches within a constrained maze. Together, these results suggest that flies enact local searches in response to a wide variety of food-associated cues, and that these sensory pathways may converge upon a common neural system for path integration. Optogenetically induced local searches in Drosophila can now serve as a tractable system for the study of spatial memory and navigation in insects.
]]></description>
<dc:creator>Corfas, R. A.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:date>2018-10-03</dc:date>
<dc:identifier>doi:10.1101/433771</dc:identifier>
<dc:title><![CDATA[Diverse food-sensing neurons trigger idiothetic local search in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/443796v1?rss=1">
<title>
<![CDATA[
Programmed Delayed Splicing: A Mechanism for Timed Inflammatory Gene Expression 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/443796v1?rss=1</link>
<description><![CDATA[
Inflammation involves timed gene expression, suggesting that the fine-tuned onset, amplitude, and termination of expression of hundreds of genes is of critical importance to organismal homeostasis. Recent study of post-transcriptional regulation of inflammatory gene expression led to the suggestion of a regulatory role for pre-mRNA splicing. Here, using a hybrid capture approach to purify incompletely spliced, chromatin-associated pre-mRNAs, we use deep sequencing to study pre-mRNA splicing of the NF-kB transcriptome. By freezing transcription and examining subsequent splicing of complete transcripts, we find many introns splice tens to hundreds of times slower than average. Investigating the basis of these delays, we focused on evolutionarily conserved introns with suboptimal splice donor sequences and found that strengthening these donor sites by as few as two nucleotides in minigene reporter assays markedly increased gene expression for several targets. This suggests that such sites can act as timing elements that both delay mRNA production and limit expression amplitude. To broaden this mechanistic view, we applied deep learning sequence-to-function models with feature attribution to identify additional regulatory sequences--both intronic and exonic--that may contribute to delayed splicing through mechanisms independent of donor site strength. This integrated approach revealed non-canonical motifs enriched in slow-splicing introns, pointing to a broader repertoire of cis-elements that can fine-tune transcript maturation during inflammation. Together, these findings support a model in which the temporal regulation of pre-mRNA splicing serves as a layer of control in inflammatory gene expression, and raise the possibility that similar timing mechanisms operate in other rapid-response transcriptional programs.
]]></description>
<dc:creator>Majumdar, D.</dc:creator>
<dc:creator>Frankiw, L.</dc:creator>
<dc:creator>Burns, C. H.</dc:creator>
<dc:creator>Garcia-Flores, Y.</dc:creator>
<dc:creator>Baltimore, D.</dc:creator>
<dc:date>2018-10-15</dc:date>
<dc:identifier>doi:10.1101/443796</dc:identifier>
<dc:title><![CDATA[Programmed Delayed Splicing: A Mechanism for Timed Inflammatory Gene Expression]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/443820v1?rss=1">
<title>
<![CDATA[
Bud13 Promotes a Type I Interferon Response By Countering Intron Retention in Irf7 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/443820v1?rss=1</link>
<description><![CDATA[
Intron retention (IR) has emerged as an important mechanism of gene expression control. Despite this, the factors that control IR events remain poorly understood. We observed consistent IR in one intron of the Irf7 gene and identified Bud13 as an RNA-binding protein that acts at this intron to increase the amount of successful splicing. Deficiency in Bud13 led to increased IR, decreased mature Irf7 transcript and protein levels, and consequently to a dampened type I interferon response. This impairment of Irf7 production in Bud13-deficient cells compromised their ability to withstand VSV infection. Global analysis of Bud13 knockdown and BUD13 cross-linking to RNA revealed a subset of introns that share many characteristics with the one found in Irf7 and are spliced in a Bud13-dependent manner. Deficiency of Bud13 led to decreased mature transcript from genes containing such introns. Thus, by acting as an antagonist to IR, Bud13 facilitates the expression of genes at which IR occurs.
]]></description>
<dc:creator>Frankiw, L. S.</dc:creator>
<dc:creator>Majumdar, D.</dc:creator>
<dc:creator>Burns, C.</dc:creator>
<dc:creator>Vlach, L.</dc:creator>
<dc:creator>Moradian, A.</dc:creator>
<dc:creator>Sweredoski, M.</dc:creator>
<dc:creator>Baltimore, D.</dc:creator>
<dc:date>2018-10-15</dc:date>
<dc:identifier>doi:10.1101/443820</dc:identifier>
<dc:title><![CDATA[Bud13 Promotes a Type I Interferon Response By Countering Intron Retention in Irf7]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/457432v1?rss=1">
<title>
<![CDATA[
Quantitative single-cell splicing analysis reveals an ‘economy of scale’ filter for gene expression 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/457432v1?rss=1</link>
<description><![CDATA[
In eukaryotic cells, splicing affects the fate of each pre-mRNA transcript, helping to determine whether it is ultimately processed into an mRNA, or degraded. The efficiency of splicing plays a key role in gene expression. However, because it depends on the levels of multiple isoforms at the same transcriptional active site (TAS) in the same cell, splicing efficiency has been challenging to measure. Here, we introduce a quantitative single-molecule FISH-based method that enables determination of the absolute abundances of distinct RNA isoforms at individual TASs. Using this method, we discovered that splicing efficiency behaves in an unexpected  economy of scale manner, increasing, rather than decreasing, with gene expression levels, opposite to a standard enzymatic process. This behavior could result from an observed correlation between splicing efficiency and spatial proximity to nuclear speckles. Economy of scale splicing represents a non-linear filter that amplifies the expression of genes when they are more strongly transcribed. This method will help to reveal the roles of splicing in the quantitative control of gene expression.
]]></description>
<dc:creator>Ding, F.</dc:creator>
<dc:creator>Elowitz, M.</dc:creator>
<dc:date>2018-10-30</dc:date>
<dc:identifier>doi:10.1101/457432</dc:identifier>
<dc:title><![CDATA[Quantitative single-cell splicing analysis reveals an ‘economy of scale’ filter for gene expression]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/504456v1?rss=1">
<title>
<![CDATA[
Controlling Organization and Forces in Active Matter Through Optically-Defined Boundaries 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/504456v1?rss=1</link>
<description><![CDATA[
Living systems are capable of locomotion, reconfiguration, and replication. To perform these tasks, cells spatiotemporally coordinate the interactions of force-generating, "active" molecules that create and manipulate non-equilibrium structures and force fields that span up to millimeter length scales [1-3]. Experimental active matter systems of biological or synthetic molecules are capable of spontaneously organizing into structures [4, 5] and generating global flows [6-9]. However, these experimental systems lack the spatiotemporal control found in cells, limiting their utility for studying non-equilibrium phenomena and bioinspired engineering. Here, we uncover non-equilibrium phenomena and principles by optically controlling structures and fluid flow in an engineered system of active biomolecules. Our engineered system consists of purified microtubules and light-activatable motor proteins that crosslink and organize microtubules into distinct structures upon illumination. We develop basic operations, defined as sets of light patterns, to create, move, and merge microtubule structures. By composing these basic operations, we are able to create microtubule networks that span several hundred microns in length and contract at speeds up to an order of magnitude faster than the speed of an individual motor. We manipulate these contractile networks to generate and sculpt persistent fluid flows. The principles of boundary-mediated control we uncover may be used to study emergent cellular structures and forces and to develop programmable active matter devices.
]]></description>
<dc:creator>Ross, T.</dc:creator>
<dc:creator>Lee, H. J.</dc:creator>
<dc:creator>Qu, Z.</dc:creator>
<dc:creator>Banks, R. A.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2018-12-21</dc:date>
<dc:identifier>doi:10.1101/504456</dc:identifier>
<dc:title><![CDATA[Controlling Organization and Forces in Active Matter Through Optically-Defined Boundaries]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-12-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/516344v1?rss=1">
<title>
<![CDATA[
Does testosterone impair men’s cognitive empathy? Evidence from two large-scale randomized controlled trials 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/516344v1?rss=1</link>
<description><![CDATA[
The capacity to infer others mental states (known as "mind reading" and "cognitive empathy") is essential for social interactions across species, and its impairment characterizes psychopathological conditions such as autism spectrum disorder and schizophrenia. Previous studies reported that testosterone administration impaired cognitive empathy in healthy humans, and that a putative biomarker of prenatal testosterone exposure (finger digit ratios) moderated the effect. However, empirical support for the relationship has relied on small-sample studies with mixed evidence. We investigate the reliability and generalizability of the relationship in two large-scale double-blind placebo-controlled experiments in young men (N=243 and N=400), using two different testosterone administration protocols. We find no evidence that cognitive empathy is impaired by testosterone administration or associated with digit ratios. With an unprecedented combined sample size, these results counter current theories and previous high-profile reports, and demonstrate that previous investigations of this topic have been statistically underpowered.
]]></description>
<dc:creator>Nadler, A.</dc:creator>
<dc:creator>Zava, D.</dc:creator>
<dc:creator>Ortiz, T.</dc:creator>
<dc:creator>Watson, N.</dc:creator>
<dc:creator>Carre, J.</dc:creator>
<dc:creator>Camerer, C.</dc:creator>
<dc:creator>Nave, G.</dc:creator>
<dc:date>2019-01-13</dc:date>
<dc:identifier>doi:10.1101/516344</dc:identifier>
<dc:title><![CDATA[Does testosterone impair men’s cognitive empathy? Evidence from two large-scale randomized controlled trials]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/516864v1?rss=1">
<title>
<![CDATA[
Human Phageprints: A high-resolution exploration of oral phages reveals globally-distributed phage families with individual-specific and temporally-stable community compositions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/516864v1?rss=1</link>
<description><![CDATA[
Metagenomic studies have revolutionized the study of novel phages. However these studies trade the depth of coverage for breadth. In this study we show that the targeted sequencing of a phage genomic region as small as 200-300 base pairs, can provide sufficient sequence diversity to serve as an individual-specific barcode or "Phageprint". The targeted approach reveals a high-resolution view of phage communities that is not available through metagenomic datasets. By creating instructional videos and collection kits, we enabled citizen scientists to gather [~]700 oral samples spanning [~]100 individuals residing in different parts of the world. In examining phage communities at 6 different oral sites, and by comparing phage communities of individuals living across the globe, we were able to study the effect of spatial separation, ranging from several millimeters to thousands of kilometers. We found that the spatial separation of just a few centimeters (the distance between two oral sites) can already result in highly distinct phage community compositions. For larger distances, spanning the phage communities of different individuals living in different parts of the world, we did not observe any correlation between spatial distance and phage community composition as individuals residing in the same city did not have any more similar phage communities than individuals living on different continents. Additionally, we found that neither genetics nor cohabitation seem to play a role in the relatedness of phage community compositions across individuals. Cohabitating siblings and even identical twins did not have phage community compositions that were any more similar than those of unrelated individuals. The primary factor contributing to phage community composition relatedness is direct contact between two habitats, as is demonstrated by the similarity between oral phage community compositions of partners. Furthermore, by exploring phage communities across the span of a month, and in some cases several years, we observed highly stable community compositions. These studies consistently point to the existence of remarkably diverse and personal phage families that are stable in time and apparently present in people around the world.
]]></description>
<dc:creator>Mahmoudabadi, G.</dc:creator>
<dc:creator>Homyk, K.</dc:creator>
<dc:creator>Catching, A.</dc:creator>
<dc:creator>Foley, H.</dc:creator>
<dc:creator>Tadmor, A.</dc:creator>
<dc:creator>Mahmoudabadi, A.</dc:creator>
<dc:creator>Cheung, A.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2019-01-10</dc:date>
<dc:identifier>doi:10.1101/516864</dc:identifier>
<dc:title><![CDATA[Human Phageprints: A high-resolution exploration of oral phages reveals globally-distributed phage families with individual-specific and temporally-stable community compositions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/525014v1?rss=1">
<title>
<![CDATA[
Prospective, brain-wide labeling of neuronal subclasses with enhancer-driven AAVs 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/525014v1?rss=1</link>
<description><![CDATA[
The rapid pace of cell type identification by new single-cell analysis methods has not been met with efficient experimental access to the newly discovered types. To enable flexible and efficient access to specific neural populations in the mouse cortex, we collected chromatin accessibility data from individual cells and clustered the single-cell data to identify enhancers specific for cell classes and subclasses. When cloned into adeno-associated viruses (AAVs) and delivered to the brain by retro-orbital injections, these enhancers drive transgene expression in specific cell subclasses in the cortex. We characterize several enhancer viruses in detail to show that they result in labeling of different projection neuron subclasses in mouse cortex, and that one of them can be used to label the homologous projection neuron subclass in human cortical slices. To enable the combinatorial labeling of more than one cell type by enhancer viruses, we developed a three-color Cre-, Flp- and Nigri-recombinase dependent reporter mouse line, Ai213. The delivery of three enhancer viruses driving these recombinases via a single retroorbital injection into a single Ai213 transgenic mouse results in labeling of three different neuronal classes/subclasses in the same brain tissue. This approach combines unprecedented flexibility with specificity for investigation of cell types in the mouse brain and beyond.
]]></description>
<dc:creator>Graybuck, L. T.</dc:creator>
<dc:creator>Sedeno-Cortes, A.</dc:creator>
<dc:creator>Nguyen, T. N.</dc:creator>
<dc:creator>Walker, M.</dc:creator>
<dc:creator>Szelenyi, E.</dc:creator>
<dc:creator>Lenz, G.</dc:creator>
<dc:creator>Sieverts, L.</dc:creator>
<dc:creator>Kim, T. K.</dc:creator>
<dc:creator>Garren, E.</dc:creator>
<dc:creator>Kalmbach, B.</dc:creator>
<dc:creator>Yao, S.</dc:creator>
<dc:creator>Mortrud, M.</dc:creator>
<dc:creator>Mich, J.</dc:creator>
<dc:creator>Goldy, J.</dc:creator>
<dc:creator>Smith, K. A.</dc:creator>
<dc:creator>Dee, N.</dc:creator>
<dc:creator>Yao, Z.</dc:creator>
<dc:creator>Cetin, A.</dc:creator>
<dc:creator>Levi, B. P.</dc:creator>
<dc:creator>Lein, E.</dc:creator>
<dc:creator>Ting, J.</dc:creator>
<dc:creator>Zeng, H.</dc:creator>
<dc:creator>Daigle, T.</dc:creator>
<dc:creator>Tasic, B.</dc:creator>
<dc:date>2019-01-20</dc:date>
<dc:identifier>doi:10.1101/525014</dc:identifier>
<dc:title><![CDATA[Prospective, brain-wide labeling of neuronal subclasses with enhancer-driven AAVs]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/531988v1?rss=1">
<title>
<![CDATA[
The fitness cost of a congenital heart defect shapes its genetic architecture 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/531988v1?rss=1</link>
<description><![CDATA[
BackgroundIn newborns, severe congenital heart defects are rarer than mild ones. The reason why is unknown, but presumably related to a liability threshold that rises with the severity of a defect. Because the same genetic mutation can cause different defects, other variables may contribute to pushing an individual past a defect-specific liability threshold. We consider here how variables in the genetic architecture of a heart defect depend upon its fitness cost, as defined by the likelihood of survival to reproductive age in natural history studies.

MethodsWe phenotyped ~10,000 Nkx2-5+/- newborn mice, a model of human congenital heart disease, from two inbred strain crosses. Genome-wide association analyses detected loci that modify the risk of an atrial septal defect, membranous or muscular ventricular septal defect, or atrioventricular septal defect. The number of loci, heritability and quantitative effects on risk of pairwise (GxGNkx) and higher-order (GxGxGNkx) epistasis between the loci and Nkx2-5 mutation were examined as a function of the fitness cost of a defect.

ResultsNkx2-5+/- mice have pleiotropic heart defects; about 70% have normal hearts. The model recapitulates the epidemiological relationship between the severity and incidence of a heart defect. Neither the number of modifier loci nor heritability depends upon the severity of a defect, but GxGNkx and GxGxGNkx effects on risk do. Interestingly, GxGxGNkx effects are three times more likely to suppress risk when the genotypes at the first two loci are homozygous and from the same, rather than opposite strains in a cross. Syn- and anti-homozygous genotypes at GxGxGNkx interactions can have an especially large impact on the risk of an atrioventricular septal defect.

ConclusionsGiven a modestly penetrant mutation, epistasis contributes more to the risk of severe than mild congenital heart defect. Conversely, genetic compatibility between interacting genes, as indicated by the protective effects of syn-homozygosity at GxGxGNkx interactions, plays a newfound role in the robustness of cardiac development. The experimental model offers practical insights into the nature of genetic risk in congenital heart disease. The results more fundamentally address a longstanding question regarding how mutational robustness could arise from natural selection.
]]></description>
<dc:creator>Akhirome, E. O.</dc:creator>
<dc:creator>Regmi, S. D.</dc:creator>
<dc:creator>Magnan, R.</dc:creator>
<dc:creator>Ugwu, N.</dc:creator>
<dc:creator>Qin, Y.</dc:creator>
<dc:creator>Schulkey, C. E.</dc:creator>
<dc:creator>Cheverud, J. M.</dc:creator>
<dc:creator>Jay, P. Y.</dc:creator>
<dc:date>2019-01-27</dc:date>
<dc:identifier>doi:10.1101/531988</dc:identifier>
<dc:title><![CDATA[The fitness cost of a congenital heart defect shapes its genetic architecture]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-01-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/548032v1?rss=1">
<title>
<![CDATA[
Repressive gene regulation synchronizes development with cellular metabolism 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/548032v1?rss=1</link>
<description><![CDATA[
Metabolic conditions affect the developmental tempo of most animal species. Consequently, developmental gene regulatory networks (GRNs) must faithfully adjust their dynamics to a variable time scale. We find evidence that layered weak repression of genes provides the necessary coupling between GRN output and cellular metabolism. Using a mathematical model that replicates such a scenario, we find that lowering metabolism corrects developmental errors that otherwise occur when different layers of repression are lost. Through mutant analysis, we show that gene expression dynamics are unaffected by loss of repressors, but only when cellular metabolism is reduced. We further show that when metabolism is lowered, formation of a variety of sensory organs in Drosophila is normal despite loss of individual repressors of transcription, mRNA stability, and protein stability. We demonstrate the universality of this phenomenon by experimentally eliminating the entire microRNA family of repressors, and find that all microRNAs are rendered unnecessary when metabolism is reduced. Thus, layered weak repression provides robustness through error frequency suppression, and may provide an evolutionary route to a shorter reproductive cycle.
]]></description>
<dc:creator>Cassidy, J. J.</dc:creator>
<dc:creator>Bernasek, S.</dc:creator>
<dc:creator>Bakker, R.</dc:creator>
<dc:creator>Giri, R.</dc:creator>
<dc:creator>Pelaez, N.</dc:creator>
<dc:creator>Eder, B.</dc:creator>
<dc:creator>Bobrowska, A.</dc:creator>
<dc:creator>Bagheri, N.</dc:creator>
<dc:creator>Amaral, L. A.</dc:creator>
<dc:creator>Carthew, R. W.</dc:creator>
<dc:date>2019-02-12</dc:date>
<dc:identifier>doi:10.1101/548032</dc:identifier>
<dc:title><![CDATA[Repressive gene regulation synchronizes development with cellular metabolism]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-02-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/565606v1?rss=1">
<title>
<![CDATA[
Machine learning-guided channelrhodopsin engineering enables minimally-invasive optogenetics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/565606v1?rss=1</link>
<description><![CDATA[
We have engineered light-gated channelrhodopsins (ChRs) whose current strength and light sensitivity enable minimally-invasive neuronal circuit interrogation. Current ChR tools applied to the mammalian brain require intracranial surgery for transgene delivery and implantation of invasive fiber-optic cables to produce light-dependent activation of a small volume of brain tissue [~1 mm3]. To enable optogenetics for large brain volumes and without the need for invasive implants, our ChR engineering approach leverages the significant literature of ChR variants to train statistical models for the design of new, high-performance ChRs. With Gaussian Process models trained on a limited experimental set of 102 functionally characterized ChR variants, we designed high-photocurrent ChRs with unprecedented light sensitivity; three of these, ChRger1, ChRger2, and ChRger3, enable optogenetic activation of the nervous system via minimally-invasive systemic transgene delivery with rAAV-PHP.eB, which was not possible previously due to low per-cell transgene copy produced by systemic delivery. These engineered ChRs enable light-induced neuronal excitation without invasive intracranial surgery for virus delivery or fiber optic implantation, i.e. they enable minimally-invasive optogenetics.
]]></description>
<dc:creator>Bedbrook, C. N.</dc:creator>
<dc:creator>Yang, K. K.</dc:creator>
<dc:creator>Robinson, J. E.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:creator>Arnold, F. H.</dc:creator>
<dc:date>2019-03-03</dc:date>
<dc:identifier>doi:10.1101/565606</dc:identifier>
<dc:title><![CDATA[Machine learning-guided channelrhodopsin engineering enables minimally-invasive optogenetics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/572974v1?rss=1">
<title>
<![CDATA[
A response to Zhang et al. (2018), \"Can Mouse-tracking Reveal Attribute Processing Speeds in Dietary Self-control? Commentary on Sullivan et al. (2015) and Lim et al. (2018)\" 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/572974v1?rss=1</link>
<description><![CDATA[
Introduction Introduction References In Sullivan et al. (2015), mouse-tracking was used in a food choice paradigm to test two related hypotheses: 1) that there are differences in the relative speed with which the decision-making circuitry computes and weights the value of attributes like health and taste; and, 2) that individual differences in these relative speeds are associated with individual differences in the ability to make healthy dietary choices. Consistent with these hypotheses, a regression analysis of the mouse-tracking paths found that health became significantly predictive of the mouses angle of movement ~195 ms later than taste, on average. Moreover, individual dietary self-control varied with estimates of the individual differences in the relative speed with which taste (tTaste) and health (tHealth) entered the decision-making process. Similar results have ...
]]></description>
<dc:creator>Sullivan, N. J.</dc:creator>
<dc:creator>Hutcherson, C.</dc:creator>
<dc:creator>Harris, A. M.</dc:creator>
<dc:creator>Rangel, A.</dc:creator>
<dc:date>2019-03-11</dc:date>
<dc:identifier>doi:10.1101/572974</dc:identifier>
<dc:title><![CDATA[A response to Zhang et al. (2018), \"Can Mouse-tracking Reveal Attribute Processing Speeds in Dietary Self-control? Commentary on Sullivan et al. (2015) and Lim et al. (2018)\"]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/597989v1?rss=1">
<title>
<![CDATA[
How the Avidity of Polymerase Binding to the -35/-10 Promoter Sites Affects Gene Expression 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/597989v1?rss=1</link>
<description><![CDATA[
Although the key promoter elements necessary to drive transcription in Escherichia coli have long been understood, we still cannot predict the behavior of arbitrary novel promoters, hampering our ability to characterize the myriad of sequenced regulatory architectures as well as to design novel synthetic circuits. This work builds on a beautiful recent experiment by Urtecho et al. who measured the gene expression of over 10,000 promoters spanning all possible combinations of a small set of regulatory elements. Using this data, we demonstrate that a central claim in energy matrix models of gene expression - that each promoter element contributes independently and additively to gene expression - contradicts experimental measurements. We propose that a key missing ingredient from such models is the avidity between the -35 and -10 RNA polymerase binding sites and develop what we call a refined energy matrix model that incorporates this effect. We show that this the refined energy matrix model can characterize the full suite of gene expression data and explore several applications of this framework, namely, how multivalent binding at the -35 and -10 sites can buffer RNAP kinetics against mutations and how promoters that bind overly tightly to RNA polymerase can inhibit gene expression. The success of our approach suggests that avidity represents a key physical principle governing the interaction of RNA polymerase to its promoter.nnSignificance StatementCellular behavior is ultimately governed by the genetic program encoded in its DNA and through the arsenal of molecular machines that actively transcribe its genes, yet we lack the ability to predict how an arbitrary DNA sequence will perform. To that end, we analyze the performance of over 10,000 regulatory sequences and develop a model that can predict the behavior of any sequence based on its composition. By considering promoters that only vary by one or two elements, we can characterize how different components interact, providing fundamental insights into the mechanisms of transcription.
]]></description>
<dc:creator>Einav, T.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2019-04-04</dc:date>
<dc:identifier>doi:10.1101/597989</dc:identifier>
<dc:title><![CDATA[How the Avidity of Polymerase Binding to the -35/-10 Promoter Sites Affects Gene Expression]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-04-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/614529v1?rss=1">
<title>
<![CDATA[
Tunable integrase-mediated differentiation facilitates improved output of burdensome functions in E. coli 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/614529v1?rss=1</link>
<description><![CDATA[
Advances in synthetic biology, bioengineering, and computation allow us to rapidly and reliably program cells with increasingly complex and useful functions. However, because the functions we engineer cells to perform are typically unnecessary for cellular survival and burdensome to cell growth, they can be rapidly lost due to the processes of mutation and natural selection. To improve the evolutionary stability of engineered functions in a general manner, we developed an integrase-recombination-based differentiation gene circuit in Escherichia coli. In this system, differentiated cells uniquely carry out burdensome or toxic engineered functions but have limited capacity to grow (terminal differentiation), preventing the propagation of selectively advantageous loss of function mutations that inevitably arise. To experimentally implement terminal differentiation, we co-opted the R6K plasmid system, using differentiation to simultaneously activate T7 RNAP-driven expression of arbitrary engineered functions, and inactivate expression of {pi} protein (an essential factor for R6K plasmid replication), thereby allowing limitation of differentiated cell growth through antibiotic selection. We experimentally demonstrate terminal differentiation increases both duration and magnitude of high-burden T7 RNAP-driven expression, and that its evolutionary stability can be further improved with strategic redundancy. Using burdensome overexpression of a fluorescent protein as a model engineered function, our terminal differentiation circuit results in a ~2.8-fold (single-cassette) and ~4.2-fold (two-cassette) increase of total fluorescent protein produced compared to high-burden naive expression in which all cells inducibly express T7 RNAP. Finally, we demonstrate that differentiation can enable the expression of even toxic functions, a feat not achieved to our knowledge by any other strategy for addressing long-term evolutionary stability. Overall, this study provides an effective generalizable strategy for protecting engineered functions from evolutionary degradation.
]]></description>
<dc:creator>Williams, R. L.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2019-04-20</dc:date>
<dc:identifier>doi:10.1101/614529</dc:identifier>
<dc:title><![CDATA[Tunable integrase-mediated differentiation facilitates improved output of burdensome functions in E. coli]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-04-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/632174v1?rss=1">
<title>
<![CDATA[
Control of density and composition in an engineered two-member bacterial community 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/632174v1?rss=1</link>
<description><![CDATA[
As studies continue to demonstrate how our health is related to the status of our various commensal microbiomes, synthetic biologists are developing tools and approaches to control these microbiomes and stabilize healthy states or remediate unhealthy ones. Building on previous work to control bacterial communities, we have constructed a synthetic two-member bacterial consortium engineered to reach population density and composition steady states set by inducer inputs. We detail a screening strategy to search functional parameter space in this high-complexity genetic circuit as well as initial testing of a functional two-member circuit.nnWe demonstrate non-independent changes in total population density and composition steady states with a limited set of varying inducer concentrations. After a dilution to perturb the system from its steady state, density and composition steady states are not regained. Modeling and simulation suggest a need for increased degradation of intercellular signals to improve circuit performance. Future experiments will implement increased signal degradation and investigate the robustness of control of each characteristic to perturbations from steady states.
]]></description>
<dc:creator>McCardell, R. D.</dc:creator>
<dc:creator>Pandey, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2019-05-09</dc:date>
<dc:identifier>doi:10.1101/632174</dc:identifier>
<dc:title><![CDATA[Control of density and composition in an engineered two-member bacterial community]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-05-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/647057v1?rss=1">
<title>
<![CDATA[
Design of a genetic layered feedback controller in synthetic biological circuitry 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/647057v1?rss=1</link>
<description><![CDATA[
Feedback control is the key to achieve robust performances for many engineered systems. However, its application in biological contexts is still largely unexplored. In this work, we designed, analyzed and simulated a layered controller functioning at both molecular and populational levels. First, we used a minimal model of three states to represent a system where state A activates state B; state R is a by-product of state B that acts as a negative feedback regulating both state A, B, and sequentially R. We call the feedback applied to state B a cis feedback and the one applied to state A a trans feedback. Through stability analysis via linearization at equilibrium and sensitivity analysis at transient state, we found that the cis feedback attenuates disturbances better but recovers slower; the trans feedback recovers faster but has more dramatic responses to fluctuations; the layered feedback demonstrates both advantageous traits of the two single layers. Then we designed two versions of synthetic genetic circuits to implement the layered controller in living cells. One version with an sRNA as regulator R, the other with a transcription factor protein as the regulator R. The analysis and dynamical simulation of the models confirmed the analytical results from the minimal model. At the same time, we found that the protein regulated feedback controls have faster recovery speed but the RNA version has a stronger disturbance attenuation effect.
]]></description>
<dc:creator>Hu, C. Y.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2019-05-24</dc:date>
<dc:identifier>doi:10.1101/647057</dc:identifier>
<dc:title><![CDATA[Design of a genetic layered feedback controller in synthetic biological circuitry]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-05-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/679910v1?rss=1">
<title>
<![CDATA[
Regular Architecture (RegArch): A standard expression language for describing protein architectures 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/679910v1?rss=1</link>
<description><![CDATA[
Domain architecture - the arrangement of features in a protein - exhibits syntactic patterns similar to the grammar of a language. This feature enables pattern mining for protein function prediction, comparative genomics, and studies of molecular evolution and complexity. To facilitate such work, here we propose Regular Architecture (RegArch), an expression language to describe syntactic patterns in protein architectures. Like the well-known Regular Expressions for text, RegArchs codify positional and non-positional patterns of elements into nested JSON objects. We describe the standard and provide a reference implementation in JavaScript to parse RegArchs and match annotated proteins.
]]></description>
<dc:creator>Ortega, D. R.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2019-06-22</dc:date>
<dc:identifier>doi:10.1101/679910</dc:identifier>
<dc:title><![CDATA[Regular Architecture (RegArch): A standard expression language for describing protein architectures]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-06-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/680090v1?rss=1">
<title>
<![CDATA[
Coordination of tissue cell polarity by auxin transport and signaling 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/680090v1?rss=1</link>
<description><![CDATA[
Coordination of polarity between cells in tissues is key to multicellular organism development. In animals, coordination of this tissue cell polarity often requires direct cell-cell interactions and cell movements, which are precluded in plants by a wall that separates cells and holds them in place; yet plants coordinate the polarity of hundreds of cells during the formation of the veins in their leaves. Overwhelming experimental evidence suggests that the plant signaling molecule auxin coordinates tissue cell polarity to induce vein formation, but how auxin does so is unclear. The prevailing hypothesis proposes that GNOM, a regulator of vesicle formation during protein trafficking, positions auxin transporters of the PIN-FORMED family to the correct side of the plasma membrane. The resulting cell-to-cell, polar transport of auxin would coordinate tissue cell polarity and would induce vein formation. Here we tested this hypothesis by means of a combination of cellular imaging, molecular genetic analysis, and chemical induction and inhibition. Contrary to predictions of the hypothesis, we find that auxin-induced vein formation occurs in the absence of PIN-FORMED proteins or any known intercellular auxin transporter, that the residual auxin-transport-independent vein-patterning activity relies on auxin signaling, and that a GNOM-dependent signal that coordinates tissue cell polarity to induce vein formation acts upstream of both auxin transport and signaling. Our results reveal synergism between auxin transport and signaling, and their unsuspected control by GNOM, in the coordination of tissue cell polarity during vein patterning, one of the most spectacular and informative expressions of tissue cell polarization in plants.
]]></description>
<dc:creator>Verna, C.</dc:creator>
<dc:creator>Ravichandran, S. J.</dc:creator>
<dc:creator>Sawchuk, M. G.</dc:creator>
<dc:creator>Linh, N. M.</dc:creator>
<dc:creator>Scarpella, E.</dc:creator>
<dc:date>2019-07-11</dc:date>
<dc:identifier>doi:10.1101/680090</dc:identifier>
<dc:title><![CDATA[Coordination of tissue cell polarity by auxin transport and signaling]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-07-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/704023v1?rss=1">
<title>
<![CDATA[
Estimating the heritability of psychological measures in the Human Connectome Project dataset 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/704023v1?rss=1</link>
<description><![CDATA[
The Human Connectome Project (HCP) is a large structural and functional MRI dataset with a rich array of behavioral measures and extensive family structure. This makes it a valuable resource for investigating questions about individual differences, including questions about heritability. While its MRI data have been analyzed extensively in this regard, to our knowledge a comprehensive estimation of the heritability of the behavioral dataset has never been conducted. Using a set of behavioral measures of personality, emotion and cognition, we show that it is possible to re-identify the same individual across two testing times, and identify identical twins. Using machine-learning (univariate linear model, Ridge classifier and Random Forest model) we estimated the heritability of 37 behavioral measures and compared the results to those derived from twin correlations. Correlations between the standard heritability metric and each set of model weights ranged from 0.42 to 0.67, and questionnaire-based and task-based measures did not differ significantly in their heritability. We further derived nine latent factors from the 37 measures and repeated the heritability estimation; in this case, the correlations between the standard heritability and each set of model weights were lower, ranging from 0.15 to 0.38. One specific discrepancy arose for the general intelligence factor, which all models assigned high importance, but the standard heritability calculation did not. We present an alternative method for qualitatively estimating the heritability of the behavioral measures in the HCP as a resource for other investigators, and recommend the use of machine-learning models for estimating heritability.
]]></description>
<dc:creator>Han, Y.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:date>2019-07-16</dc:date>
<dc:identifier>doi:10.1101/704023</dc:identifier>
<dc:title><![CDATA[Estimating the heritability of psychological measures in the Human Connectome Project dataset]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-07-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/743799v1?rss=1">
<title>
<![CDATA[
Characterization of the brain functional architecture of psychostimulant withdrawal using single-cell whole brain imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/743799v1?rss=1</link>
<description><![CDATA[
Numerous brain regions have been identified as contributing to addiction-like behaviors, but unclear is the way in which these brain regions as a whole lead to addiction. The search for a final common brain pathway that is involved in addiction remains elusive. To address this question, we used male C57BL/6J mice and performed single-cell whole-brain imaging of neural activity during withdrawal from cocaine, methamphetamine, and nicotine. We used hierarchical clustering and graph theory to identify similarities and differences in brain functional architecture. Although methamphetamine and cocaine shared some network similarities, the main common neuroadaptation between these psychostimulant drugs was a dramatic decrease in modularity, with a shift from a cortical- to subcortical-driven network, including a decrease in total hub brain regions. These results demonstrate that psychostimulant withdrawal produces the drug-dependent remodeling of functional architecture of the brain and suggest that the decreased modularity of brain functional networks and not a specific set of brain regions may represent the final common pathway that leads to addiction.nnSignificance StatementA key aspect of treating drug abuse is understanding similarities and differences of how drugs of abuse affect the brain. In the present study we examined how the brain is altered during withdrawal from psychostimulants. We found that each drug produced a unique pattern of activity in the brain, but that brains in withdrawal from cocaine and methamphetamine shared similar features. Interestingly, we found the major common link between withdrawal from all psychostimulants, when compared to controls, was a shift in the broad organization of the brain in the form of reduced modularity. Reduced modularity has been shown in several brain disorders, including traumatic brain injury, and dementia, and may be the common link between drugs of abuse.
]]></description>
<dc:creator>Kimbrough, A.</dc:creator>
<dc:creator>Smith, L. C.</dc:creator>
<dc:creator>Kallupi, M.</dc:creator>
<dc:creator>Simpson, S.</dc:creator>
<dc:creator>Collazo, A.</dc:creator>
<dc:creator>George, O.</dc:creator>
<dc:date>2019-08-22</dc:date>
<dc:identifier>doi:10.1101/743799</dc:identifier>
<dc:title><![CDATA[Characterization of the brain functional architecture of psychostimulant withdrawal using single-cell whole brain imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-08-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/758557v1?rss=1">
<title>
<![CDATA[
A metabolic pathway for bile acid dehydroxylation by the gut microbiome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/758557v1?rss=1</link>
<description><![CDATA[
The gut microbiota synthesize hundreds of molecules, many of which are known to impact host physiology. Among the most abundant metabolites are the secondary bile acids deoxycholic acid (DCA) and lithocholic acid (LCA), which accumulate at ~500 M and are known to block C. difficile growth1, promote hepatocellular carcinoma2, and modulate host metabolism via the GPCR TGR53. More broadly, DCA, LCA and their derivatives are a major component of the recirculating bile acid pool4; the size and composition of this pool are a target of therapies for primary biliary cholangitis and nonalcoholic steatohepatitis. Despite the clear impact of DCA and LCA on host physiology, incomplete knowledge of their biosynthetic genes and a lack of genetic tools in their native producer limit our ability to modulate secondary bile acid levels in the host. Here, we complete the pathway to DCA/LCA by assigning and characterizing enzymes for each of the steps in its reductive arm, revealing a strategy in which the A-B rings of the steroid core are transiently converted into an electron acceptor for two reductive steps carried out by Fe-S flavoenzymes. Using anaerobic in vitro reconstitution, we establish that a set of six enzymes is necessary and sufficient for the 8-step conversion of cholic acid to DCA. We then engineer the pathway into Clostridium sporogenes, conferring production of DCA and LCA on a non-producing commensal and demonstrating that a microbiome-derived pathway can be expressed and controlled heterologously. These data establish a complete pathway to two central components of the bile acid pool, and provide a road map for deorphaning and engineering pathways from the microbiome as a critical step toward controlling the metabolic output of the gut microbiota.
]]></description>
<dc:creator>Funabashi, M.</dc:creator>
<dc:creator>Grove, T.</dc:creator>
<dc:creator>Pascal, V.</dc:creator>
<dc:creator>Varma, Y.</dc:creator>
<dc:creator>McFadden, M.</dc:creator>
<dc:creator>Brown, L.</dc:creator>
<dc:creator>Guo, C.</dc:creator>
<dc:creator>Medema, M. H.</dc:creator>
<dc:creator>Almo, S.</dc:creator>
<dc:creator>Fischbach, M. A.</dc:creator>
<dc:date>2019-09-05</dc:date>
<dc:identifier>doi:10.1101/758557</dc:identifier>
<dc:title><![CDATA[A metabolic pathway for bile acid dehydroxylation by the gut microbiome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-09-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/774042v1?rss=1">
<title>
<![CDATA[
Assessment of Robustness to Temperature in a Negative Feedback Loop and a Feedforward Loop 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/774042v1?rss=1</link>
<description><![CDATA[
Robustness to temperature variation is an important specification for biomolecular circuit design. While cancellation of parametric temperature dependences has been shown to improve temperature robustness of period in a synthetic oscillator design, the performance of other biomolecular circuit designs in different temperature conditions is relatively unclear. Using a combination of experimental measurements and mathematical models, we assess the temperature robustness of two biomolecular circuit motifs -- a negative feedback loop and a feedforward loop. We find that the measured responses in both circuits can change with temperature, both in the amplitude and in the transient response. We find that, in addition to the cancellation of parametric temperature dependencies, certain parameter regimes can also facilitate temperature robustness for the negative feedback loop, although at a performance cost. We discuss these parameter regimes of operation in the context of the measured data for the negative feedback loop. These results should help develop a framework for assessing and designing temperature robustness in biomolecular circuits.
]]></description>
<dc:creator>Patel, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:creator>Sen, S.</dc:creator>
<dc:date>2019-09-18</dc:date>
<dc:identifier>doi:10.1101/774042</dc:identifier>
<dc:title><![CDATA[Assessment of Robustness to Temperature in a Negative Feedback Loop and a Feedforward Loop]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-09-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/775783v1?rss=1">
<title>
<![CDATA[
Fly-QMA: Automated analysis of mosaic imaginal discs in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/775783v1?rss=1</link>
<description><![CDATA[
Mosaic analysis provides a means to probe developmental processes in situ by generating loss-of-function mutants within otherwise wildtype tissues. Combining these techniques with quantitative microscopy enables researchers to rigorously compare RNA or protein expression across the resultant clones. However, visual inspection of mosaic tissues remains common in the literature because quantification demands considerable labor and computational expertise. Practitioners must segment cell membranes or cell nuclei from a tissue and annotate the clones before their data are suitable for analysis. Here, we introduce Fly-QMA, a computational framework that automates each of these tasks for confocal microscopy images of Drosophila imaginal discs. The framework includes an unsupervised annotation algorithm that incorporates spatial context to inform the genetic identity of each cell. We use a combination of real and synthetic validation data to survey the performance of the annotation algorithm across a broad range of conditions. By contributing our framework to the open-source software ecosystem, we aim to contribute to the current move toward automated quantitative analysis among developmental biologists.nnAuthor summaryBiologists use mosaic tissues to compare the behavior of genetically distinct cells within an otherwise equivalent context. The ensuing analysis is often limited to qualitative insight. However, it is becoming clear that quantitative models are needed to unravel the complexities of many biological systems. In this manuscript we introduce Fly-QMA, an open-source software framework that automates the quantification of mosaic analysis for Drosophila imaginal discs, a common setting for studies of developmental processes. The software automatically extracts quantitative measurements from confocal images of mosaic tissues, rectifies any cross-talk between fluorescent reporters, and identifies clonally-related subpopulations of cells. Together, these functions allow users to rigorously ascribe changes in gene expression to the presence or absence of particular genes. We validate the performance of our framework using both real and synthetic data. Through its publication, we aim to contribute to the current move toward automated quantitative analysis among biologists.
]]></description>
<dc:creator>Bernasek, S. M.</dc:creator>
<dc:creator>Pelaez, N.</dc:creator>
<dc:creator>Carthew, R.</dc:creator>
<dc:creator>Bagheri, N.</dc:creator>
<dc:creator>Amaral, L.</dc:creator>
<dc:date>2019-09-19</dc:date>
<dc:identifier>doi:10.1101/775783</dc:identifier>
<dc:title><![CDATA[Fly-QMA: Automated analysis of mosaic imaginal discs in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-09-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/779363v1?rss=1">
<title>
<![CDATA[
The structure of behavioral variation within a genotype 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/779363v1?rss=1</link>
<description><![CDATA[
Individual animals vary in their behaviors. This is true even when they share the same genotype and were reared in the same environment. Clusters of covarying behaviors constitute behavioral syndromes, and an individuals position along such axes of covariation is a representation of their personality. Despite these conceptual frameworks, the structure of behavioral covariation within a genotype is essentially uncharacterized and its mechanistic origins unknown. Passing hundreds of inbred Drosophila individuals through an experimental pipeline that captured hundreds of behavioral measures, we found correlations only between sparse pairs of behaviors. Thus, the space of behavioral variation has many independent dimensions. Manipulating the physiology of the brain, and specific neural populations, altered specific correlations. We also observed that variation in gene expression can predict an individuals position on some behavior axes. This work represents the first steps in understanding the biological mechanisms determining the structure of behavioral variation within a genotype.
]]></description>
<dc:creator>Werkhoven, Z.</dc:creator>
<dc:creator>Bravin, A.</dc:creator>
<dc:creator>Skutt-Kakaria, K.</dc:creator>
<dc:creator>Reimers, P.</dc:creator>
<dc:creator>Pallares, L. F.</dc:creator>
<dc:creator>Ayroles, J.</dc:creator>
<dc:creator>de Bivort, B. L.</dc:creator>
<dc:date>2019-09-23</dc:date>
<dc:identifier>doi:10.1101/779363</dc:identifier>
<dc:title><![CDATA[The structure of behavioral variation within a genotype]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-09-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/783480v1?rss=1">
<title>
<![CDATA[
A dynamic pattern of local auxin sources is required for root regeneration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/783480v1?rss=1</link>
<description><![CDATA[
Following removal of its stem cell niche, the root meristem can regenerate by recruitment of remnant cells from the stump. Regeneration is initiated by rapid accumulation of auxin near the injury site but the source of this auxin is unknown. Here, we show that auxin accumulation arises from the activity of multiple auxin biosynthetic sources that are newly specified near the cut site and that their continuous activity is required for the regeneration process. Auxin synthesis is highly localized and PIN-mediate transport is dispensable for auxin accumulation and tip regeneration. Roots lacking the activity of the regeneration competence factor ERF115, or that are dissected at a zone of low-regeneration potential, fail to activate local auxin sources. Remarkably, restoring auxin supply is sufficient to confer regeneration capacity to these recalcitrant tissues. We suggest that regeneration competence relies on the ability to specify new local auxin sources in a precise spatio-temporal pattern.
]]></description>
<dc:creator>Matosevich, R.</dc:creator>
<dc:creator>Cohen, I.</dc:creator>
<dc:creator>Gil-Yarom, N.</dc:creator>
<dc:creator>Modrego, A.</dc:creator>
<dc:creator>Verna, C.</dc:creator>
<dc:creator>Scarpella, E.</dc:creator>
<dc:creator>Efroni, I.</dc:creator>
<dc:date>2019-09-26</dc:date>
<dc:identifier>doi:10.1101/783480</dc:identifier>
<dc:title><![CDATA[A dynamic pattern of local auxin sources is required for root regeneration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-09-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/797126v1?rss=1">
<title>
<![CDATA[
A neural circuit basis for context-modulation of individual locomotor behavior 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/797126v1?rss=1</link>
<description><![CDATA[
Defying the cliche that biological variation arises from differences in nature or nurture, genetically identical animals reared in the same environment exhibit striking differences in their behaviors. Innate behaviors can be surprisingly flexible, for example by exhibiting context-dependence. The intersection of behavioral individuality and context-dependence is largely unexplored, particularly at the neural circuit level. Here, we show that individual flies tendencies to turn left or right (locomotor handedness) changes when ambient illumination changes. This change is itself a stable individual behavioral characteristic. Silencing output neurons of the central complex (a premotor area that mediates goal-directed navigation) blocks this change. These neurons respond to light with idiosyncratic changes to their baseline calcium levels, and idiosyncratic morphological variation in their presynaptic arbors correlates with idiosyncratic sensory-context-specific turn biases. These findings provide a circuit mechanism by which individual locomotor biases arise and are modulated by sensory context.
]]></description>
<dc:creator>Skutt-Kakaria, K.</dc:creator>
<dc:creator>Reimers, P.</dc:creator>
<dc:creator>Currier, T. A.</dc:creator>
<dc:creator>Werkhoven, Z.</dc:creator>
<dc:creator>de Bivort, B. L.</dc:creator>
<dc:date>2019-10-08</dc:date>
<dc:identifier>doi:10.1101/797126</dc:identifier>
<dc:title><![CDATA[A neural circuit basis for context-modulation of individual locomotor behavior]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/809673v1?rss=1">
<title>
<![CDATA[
Flexible recruitment of memory-based choice representations by human medial-frontal cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/809673v1?rss=1</link>
<description><![CDATA[
Decisions in complex environments rely on flexibly utilizing past experience as required by context and instructions1. This process depends on the medial frontal cortex (MFC) and the medial temporal lobe (MTL)2-5, but it remains unknown how these structures jointly implement flexible memory retrieval6,7. We recorded single neurons in MFC and MTL while human subjects switched8 between making memory- and categorization-based decisions9,10. Here we show that MFC rapidly implements changing task demands by utilizing different subspaces of neural activity during different types of decisions. In contrast, no effect of task demands was seen in the MTL. Choices requiring memory retrieval selectively engaged phase-locking of MFC neurons to field potentials in the theta-frequency band in the MTL. Choice-selective neurons in MFC signaled abstract yes-no decisions independent of behavioral response modality (button press or saccade). These findings reveal a novel mechanism for flexibly and selectively engaging memory retrieval11-14 and show that unlike perceptual decision-making15, memory-related information is only represented in frontal cortex when choices require it.
]]></description>
<dc:creator>Minxha, J.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:creator>Fusi, S.</dc:creator>
<dc:creator>Mamelak, A.</dc:creator>
<dc:creator>Rutishauser, U.</dc:creator>
<dc:date>2019-10-18</dc:date>
<dc:identifier>doi:10.1101/809673</dc:identifier>
<dc:title><![CDATA[Flexible recruitment of memory-based choice representations by human medial-frontal cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/820217v1?rss=1">
<title>
<![CDATA[
Live-Cell Imaging and Quantification of PolyQ Aggregates by Stimulated Raman Scattering of Selective Deuterium Labeling 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/820217v1?rss=1</link>
<description><![CDATA[
Huntingtons disease, a major neurodegenerative disorder, involves deposition of aggregation-prone proteins with long polyglutamine (polyQ) expansions. The ability to non-perturbatively visualize the formation of aggregates could offer new molecular insight for their pathologic roles. Here, we propose stimulated Raman scattering imaging of deuterium-labeled glutamine to investigate native polyQ aggregates in live cells with subcellular resolution. Through the enrichment of deuterated glutamine in the polyQ sequence of mutant Huntingtin (mHtt) proteins, we first achieved sensitive and specific SRS imaging of carbon-deuterium bonds (C-D) from aggregates without GFP labeling. These aggregates become 1.8-fold denser compared to those with GFP. Second, we performed ratiometric quantification, which revealed a dependence of protein compositions on aggregation sizes. Moreover, we calculated the absolute concentrations for sequestered mHtt and non-mHtt proteins within the same aggregates. Our method may readily reveal new features of polyQ aggregates and could be suited for in vivo investigations on multicellular organisms.
]]></description>
<dc:creator>Miao, K.</dc:creator>
<dc:creator>Wei, L.</dc:creator>
<dc:date>2019-10-28</dc:date>
<dc:identifier>doi:10.1101/820217</dc:identifier>
<dc:title><![CDATA[Live-Cell Imaging and Quantification of PolyQ Aggregates by Stimulated Raman Scattering of Selective Deuterium Labeling]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-10-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/843193v1?rss=1">
<title>
<![CDATA[
Variability in the analysis of a single neuroimaging dataset by many teams 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/843193v1?rss=1</link>
<description><![CDATA[
Data analysis workflows in many scientific domains have become increasingly complex and flexible. To assess the impact of this flexibility on functional magnetic resonance imaging (fMRI) results, the same dataset was independently analyzed by 70 teams, testing nine ex-ante hypotheses. The flexibility of analytic approaches is exemplified by the fact that no two teams chose identical workflows to analyze the data. This flexibility resulted in sizeable variation in hypothesis test results, even for teams whose statistical maps were highly correlated at intermediate stages of their analysis pipeline. Variation in reported results was related to several aspects of analysis methodology. Importantly, meta-analytic approaches that aggregated information across teams yielded significant consensus in activated regions across teams. Furthermore, prediction markets of researchers in the field revealed an overestimation of the likelihood of significant findings, even by researchers with direct knowledge of the dataset. Our findings show that analytic flexibility can have substantial effects on scientific conclusions, and demonstrate factors related to variability in fMRI. The results emphasize the importance of validating and sharing complex analysis workflows, and demonstrate the need for multiple analyses of the same data. Potential approaches to mitigate issues related to analytical variability are discussed.
]]></description>
<dc:creator>Botvinik-Nezer, R.</dc:creator>
<dc:creator>Holzmeister, F.</dc:creator>
<dc:creator>Camerer, C.</dc:creator>
<dc:creator>Dreber, A.</dc:creator>
<dc:creator>Huber, J.</dc:creator>
<dc:creator>Johannesson, M.</dc:creator>
<dc:creator>Kirchler, M.</dc:creator>
<dc:creator>Nichols, T. E.</dc:creator>
<dc:creator>Poldrack, R. A.</dc:creator>
<dc:creator>Schonberg, T.</dc:creator>
<dc:date>2019-11-15</dc:date>
<dc:identifier>doi:10.1101/843193</dc:identifier>
<dc:title><![CDATA[Variability in the analysis of a single neuroimaging dataset by many teams]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/847970v1?rss=1">
<title>
<![CDATA[
Organogenesis and Distribution of the Ocular Lymphatic Vessels in the Anterior Eye: Implication to Glaucoma Surgery Site Selection 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/847970v1?rss=1</link>
<description><![CDATA[
Glaucoma surgeries, such as trabeculectomy, are performed to lower the intraocular pressure to reduce the risk of vision loss. The surgeries create a new passage in the eye that reroutes the aqueous humor outflow to the subconjunctival space, where the fluid is presumably absorbed by the conjunctival lymphatics. However, the current knowledge of these ocular surface lymphatics remains limited. Here, we characterized the biology and function of the ocular lymphatics using transgenic lymphatic reporter mice and rats. We found that the limbal and conjunctival lymphatic networks are progressively formed by a primary lymphatic vessel that grows out from the nasal-side medial canthus region at the time of birth. This primary lymphatic vessel immediately branches out and invades the limbus and conjunctiva, and then simultaneously encircles the cornea in a bidirectional manner. As a result, the distribution of the ocular lymphatic is significantly polarized toward the nasal side, and the limbal lymphatics are directly connected to the conjunctival lymphatics. New lymphatic spouts are mainly produced from the nasal-side limbal lymphatics, posing the nasal side of the eye more responsive to fluid drainage and inflammatory stimuli. Consistently, when a fluorescent tracer was injected, fluid clearance was much more efficient in the nasal side than the temporal side of the eyes. In comparison, blood vessels are evenly distributed on the front surface of the eyes. We found that these distinct vascular distribution patterns were also conserved in human eyes. Together, our study demonstrated that the ocular surface lymphatics are more densely present in the nasal side and uncovered the potential clinical benefits in selecting the nasal side as a surgical site for glaucoma surgeries to improve the fluid drainage.
]]></description>
<dc:creator>Wu, Y.</dc:creator>
<dc:creator>Seong, Y. J.</dc:creator>
<dc:creator>Kin, L.</dc:creator>
<dc:creator>Choi, D.</dc:creator>
<dc:creator>Park, E.</dc:creator>
<dc:creator>Daghlian, G.</dc:creator>
<dc:creator>Jung, E.</dc:creator>
<dc:creator>Bui, K.</dc:creator>
<dc:creator>Luping, Z.</dc:creator>
<dc:creator>Madhavan, S.</dc:creator>
<dc:creator>Saren, D.</dc:creator>
<dc:creator>Patill, D.</dc:creator>
<dc:creator>Chin, D.</dc:creator>
<dc:creator>Cho, I.-T.</dc:creator>
<dc:creator>Wong, A.</dc:creator>
<dc:creator>Heur, M.</dc:creator>
<dc:creator>Zhang-Nunes, S.</dc:creator>
<dc:creator>Tan, J.</dc:creator>
<dc:creator>Ema, M.</dc:creator>
<dc:creator>Huang, A. S.</dc:creator>
<dc:creator>Hong, Y.-K.</dc:creator>
<dc:date>2019-12-03</dc:date>
<dc:identifier>doi:10.1101/847970</dc:identifier>
<dc:title><![CDATA[Organogenesis and Distribution of the Ocular Lymphatic Vessels in the Anterior Eye: Implication to Glaucoma Surgery Site Selection]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/851691v1?rss=1">
<title>
<![CDATA[
Electrode pooling: How to boost the yield of switchable silicon probes for neuronal recordings 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/851691v1?rss=1</link>
<description><![CDATA[
State-of-the-art silicon probes for electrical recording from neurons have thousands of recording sites. However, due to volume limitations there are typically many fewer wires carrying signals off the probe, which restricts the number of channels that can be recorded simultaneously. To overcome this fundamental constraint, we propose a novel method called electrode pooling that uses a single wire to serve many recording sites through a set of controllable switches. Here we present the framework behind this method and an experimental strategy to support it. We then demonstrate its feasibility by implementing electrode pooling on the Neuropixels 1.0 electrode array and characterizing its effect on signal and noise. Finally we use simulations to explore the conditions under which electrode pooling saves wires without compromising the content of the recordings. We make recommendations on the design of future devices to take advantage of this strategy.
]]></description>
<dc:creator>Lee, K. H.</dc:creator>
<dc:creator>Ni, Y.-L.</dc:creator>
<dc:creator>Meister, M.</dc:creator>
<dc:date>2019-11-26</dc:date>
<dc:identifier>doi:10.1101/851691</dc:identifier>
<dc:title><![CDATA[Electrode pooling: How to boost the yield of switchable silicon probes for neuronal recordings]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/865568v1?rss=1">
<title>
<![CDATA[
Value-related neuronal responses in the human amygdala during observational learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/865568v1?rss=1</link>
<description><![CDATA[
AbstractThe amygdala plays an important role in many aspects of social-cognition and reward-learning. Here we aimed to determine whether human amygdala neurons are involved in the computations necessary to implement learning through observation. We performed single-neuron recordings from the amygdalae of human neurosurgical patients (male and female) while they learned about the value of stimuli through observing the outcomes experienced by another agent interacting with those stimuli. We used a detailed computational modeling approach to describe patients behavior in the task. Then, using both population-level decoding and single neuron analyses we found evidence to implicate amygdala neurons in two key computations relevant for observational-learning: tracking the expected future reward associated with a given stimulus, and in tracking outcome values received by oneself or other agents. Encoding and decoding analyses suggested observational value coding in amygdala neurons occurred in a different subset of neurons than experiential value coding. Collectively, these findings support a key role for the human amygdala in the computations underlying the capacity for learning through observation.

Significance statementSingle neuron studies of the human brain provide a unique window into the computational mechanisms of cognition. In this study, epilepsy patients implanted intracranially with depth microelectrodes performed an observational learning task. We measured activity bilaterally in the amygdala and found a representation for observational rewards as well as observational expected reward values. Additionally, the representation of self-experienced and observational values was performed by distinct subsets of amygdala neurons. This study thus provides a rare glimpse into the role of human amygdala neurons in social cognition.
]]></description>
<dc:creator>Aquino, T. G.</dc:creator>
<dc:creator>Minxha, J.</dc:creator>
<dc:creator>Dunne, S.</dc:creator>
<dc:creator>Ross, I. B.</dc:creator>
<dc:creator>Mamelak, A. N.</dc:creator>
<dc:creator>Rutishauser, U.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:date>2019-12-06</dc:date>
<dc:identifier>doi:10.1101/865568</dc:identifier>
<dc:title><![CDATA[Value-related neuronal responses in the human amygdala during observational learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/866632v1?rss=1">
<title>
<![CDATA[
Vein Patterning by Tissue-Specific Auxin Transport 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/866632v1?rss=1</link>
<description><![CDATA[
Unlike in animals, in plants vein patterning does not rely on direct cell-cell interaction and cell migration; instead, it depends on the transport of the plant signal auxin, which in turn depends on the activity of the PIN-FORMED1 (PIN1) auxin transporter. The current hypotheses of vein patterning by auxin transport propose that in the epidermis of the developing leaf PIN1-mediated auxin transport converges to peaks of auxin level. From those convergence points of epidermal PIN1 polarity, auxin would be transported in the inner tissues where it would give rise to major veins. Here we tested predictions of this hypothesis and found them unsupported: epidermal PIN1 expression is neither required nor sufficient for auxin-transport-dependent vein patterning, whereas inner-tissue PIN1 expression turns out to be both required and sufficient for auxin-transport-dependent vein patterning. Our results refute all vein patterning hypotheses based on auxin transport from the epidermis and suggest alternatives for future tests.
]]></description>
<dc:creator>Govindaraju, P.</dc:creator>
<dc:creator>Verna, C.</dc:creator>
<dc:creator>Zhu, T.</dc:creator>
<dc:creator>Scarpella, E.</dc:creator>
<dc:date>2019-12-06</dc:date>
<dc:identifier>doi:10.1101/866632</dc:identifier>
<dc:title><![CDATA[Vein Patterning by Tissue-Specific Auxin Transport]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.14.544094v1?rss=1">
<title>
<![CDATA[
A window to the brain: ultrasound imaging of human neural activity through a permanent acoustic window 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.14.544094v1?rss=1</link>
<description><![CDATA[
Recording human brain activity is crucial for understanding normal and aberrant brain function. However, available recording methods are either highly invasive or have relatively low sensitivity. Functional ultrasound imaging (fUSI) is an emerging technique that offers sensitive, large-scale, high-resolution neural imaging. However, fUSI cannot be performed through adult human skull. Here, we use a polymeric skull replacement material to create an acoustic window allowing ultrasound to monitor brain activity in fully intact adult humans. We design the window through experiments in phantoms and rodents, then implement it in a participant undergoing reconstructive skull surgery. Subsequently, we demonstrate fully non-invasive mapping and decoding of cortical responses to finger movement, marking the first instance of high-resolution (200 m) and large-scale (50 mmx38 mm) brain imaging through a permanent acoustic window.
]]></description>
<dc:creator>Rabut, C.</dc:creator>
<dc:creator>Norman, S. L.</dc:creator>
<dc:creator>Griggs, W. S.</dc:creator>
<dc:creator>Russin, J. J.</dc:creator>
<dc:creator>Jann, K.</dc:creator>
<dc:creator>Christopoulos, V.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2023-06-15</dc:date>
<dc:identifier>doi:10.1101/2023.06.14.544094</dc:identifier>
<dc:title><![CDATA[A window to the brain: ultrasound imaging of human neural activity through a permanent acoustic window]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.18.545353v1?rss=1">
<title>
<![CDATA[
Non-cognate immunity proteins provide broader defenses against interbacterial effectors in microbial communities 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.18.545353v1?rss=1</link>
<description><![CDATA[
Dense microbial communities, like the gut and soil microbiomes, are dynamic societies. Bacteria can navigate these environments by deploying proteins that alter foreign cells behavior, such as interbacterial effectors. Current models suggest that adjacent sibling cells are protected by an immunity protein, as compared to toxin-antitoxin systems that act only within the effector-producing cell. A prevailing hypothesis is that immunity proteins binding to specific (cognate) protein partners is sufficient to disrupt effector function. Further, there is little-to-no crosstalk with other non-cognate effectors. In this research, we build on sporadic reports challenging these hypotheses. We show that immunity proteins from a newly defined protein family can bind and protect against non-cognate PD-(D/E)XK-containing effectors from diverse phyla. We describe the domains essential for binding and function and show that binding alone is insufficient for protective activity. Moreover, we found that these effector and immunity genes co-occur in individual human microbiomes. These results expand the growing repertoire of bacterial protection mechanisms and the models on how non-cognate interactions impact community structure within complex ecosystems.
]]></description>
<dc:creator>Knecht, A.</dc:creator>
<dc:creator>Sirias, D.</dc:creator>
<dc:creator>Utter, D. R.</dc:creator>
<dc:creator>Gibbs, K. A.</dc:creator>
<dc:date>2023-06-18</dc:date>
<dc:identifier>doi:10.1101/2023.06.18.545353</dc:identifier>
<dc:title><![CDATA[Non-cognate immunity proteins provide broader defenses against interbacterial effectors in microbial communities]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.25.546328v1?rss=1">
<title>
<![CDATA[
Patterning and folding of intestinal villi by active mesenchymal dewetting 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.25.546328v1?rss=1</link>
<description><![CDATA[
Tissue folding generates structural motifs critical to organ function. In the intestine, bending of a flat epithelium into a periodic pattern of folds gives rise to villi, the numerous finger-like protrusions that are essential for nutrient absorption. However, the molecular and mechanical mechanisms driving the initiation and morphogenesis of villi remain a matter of debate. Here, we identify an active mechanical mechanism that simultaneously patterns and folds intestinal villi. We find that PDGFRA+ subepithelial mesenchymal cells generate myosin II-dependent forces sufficient to produce patterned curvature in neighboring tissue interfaces. At the cell-level, this occurs through a process dependent upon matrix metalloproteinase-mediated tissue fluidization and altered cell-ECM adhesion. By combining computational models with in vivo experiments, we reveal these cellular features manifest at the tissue-level as differences in interfacial tensions that promote mesenchymal aggregation and interface bending through a process analogous to the active de-wetting of a thin liquid film.
]]></description>
<dc:creator>Huycke, T. R.</dc:creator>
<dc:creator>Miyazaki, H.</dc:creator>
<dc:creator>Häkkinen, T.</dc:creator>
<dc:creator>Srivastava, V.</dc:creator>
<dc:creator>Barruet, E.</dc:creator>
<dc:creator>McGinnis, C. S.</dc:creator>
<dc:creator>Kalantari, A.</dc:creator>
<dc:creator>Cornwall-Scoones, J.</dc:creator>
<dc:creator>Vaka, D.</dc:creator>
<dc:creator>Zhu, Q.</dc:creator>
<dc:creator>Jo, H.</dc:creator>
<dc:creator>DeGrado, W. F.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Garikipati, K.</dc:creator>
<dc:creator>Boffelli, D.</dc:creator>
<dc:creator>Klein, O. D.</dc:creator>
<dc:creator>Gartner, Z. J.</dc:creator>
<dc:date>2023-06-26</dc:date>
<dc:identifier>doi:10.1101/2023.06.25.546328</dc:identifier>
<dc:title><![CDATA[Patterning and folding of intestinal villi by active mesenchymal dewetting]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.27.546433v1?rss=1">
<title>
<![CDATA[
50-nm gas-filled protein nanostructures to enable the access of lymphatic cells by ultrasound technologies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.27.546433v1?rss=1</link>
<description><![CDATA[
Ultrasound imaging and ultrasound-mediated gene and drug delivery are rapidly advancing diagnostic and therapeutic methods; however, their use is often limited by the need of microbubbles, which cannot transverse many biological barriers due to their large size. Here we introduce 50-nm gas-filled protein nanostructures derived from genetically engineered gas vesicles that we referred to as 50nmGVs. These diamond-shaped nanostructures have hydrodynamic diameters smaller than commercially available 50-nm gold nanoparticles and are, to our knowledge, the smallest stable, free-floating bubbles made to date. 50nmGVs can be produced in bacteria, purified through centrifugation, and remain stable for months. Interstitially injected 50nmGVs can extravasate into lymphatic tissues and gain access to critical immune cell populations, and electron microscopy images of lymph node tissues reveal their subcellular location in antigen-presenting cells adjacent to lymphocytes. We anticipate that 50nmGVs can substantially broaden the range of cells accessible to current ultrasound technologies and may generate applications beyond biomedicine as ultrasmall stable gas-filled nanomaterials.
]]></description>
<dc:creator>Shen, Q.</dc:creator>
<dc:creator>Li, Z.</dc:creator>
<dc:creator>Meyer, M. D.</dc:creator>
<dc:creator>De Guzman, M. T.</dc:creator>
<dc:creator>Lim, J. C.</dc:creator>
<dc:creator>Bouchard, R. R.</dc:creator>
<dc:creator>Lu, G. J.</dc:creator>
<dc:date>2023-06-28</dc:date>
<dc:identifier>doi:10.1101/2023.06.27.546433</dc:identifier>
<dc:title><![CDATA[50-nm gas-filled protein nanostructures to enable the access of lymphatic cells by ultrasound technologies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.27.546773v1?rss=1">
<title>
<![CDATA[
Truly tiny acoustic biomolecules for ultrasound imaging and therapy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.27.546773v1?rss=1</link>
<description><![CDATA[
Nanotechnology offers significant advantages for medical imaging and therapy, including enhanced contrast and precision targeting. However, integrating these benefits into ultrasonography has been challenging due to the size and stability constraints of conventional bubble-based agents. Here we describe bicones, truly tiny acoustic contrast agents based on gas vesicles, a unique class of air-filled protein nanostructures naturally produced in buoyant microbes. We show that these sub-80 nm particles can be effectively detected both in vitro and in vivo, infiltrate tumors via leaky vasculature, deliver potent mechanical effects through ultrasound-induced inertial cavitation, and are easily engineered for molecular targeting, prolonged circulation time, and payload conjugation.
]]></description>
<dc:creator>Ling, B.</dc:creator>
<dc:creator>Gungoren, B.</dc:creator>
<dc:creator>Yao, Y.</dc:creator>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Smith, C. A. B.</dc:creator>
<dc:creator>Lee, J.</dc:creator>
<dc:creator>Swift, M. B.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2023-06-28</dc:date>
<dc:identifier>doi:10.1101/2023.06.27.546773</dc:identifier>
<dc:title><![CDATA[Truly tiny acoustic biomolecules for ultrasound imaging and therapy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.29.547026v1?rss=1">
<title>
<![CDATA[
Processive movement of Staphylococcus aureus essential septal peptidoglycan synthases is independent of FtsZ treadmilling and drives cell constriction 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.29.547026v1?rss=1</link>
<description><![CDATA[
Bacterial cell division is mediated by the tubulin-homolog FtsZ, which recruits peptidoglycan (PG) synthesis enzymes to the division site. Septal PG synthases promote inward growth of the division septum, but the mechanisms governing the spatiotemporal regulation of these enzymes are poorly understood. Recent studies on various organisms have proposed different models for the relationship between the movement and activity of septum-specific PG synthases and FtsZ treadmilling. Here, we studied the movement dynamics of conserved cell division proteins relative to the rates of septum constriction and FtsZ treadmilling in the Gram-positive pathogen Staphylococcus aureus. The septal PG synthesis enzyme complex FtsW/PBP1 and its putative activator protein, DivIB, moved processively, around the division site, with the same velocity. Impairing FtsZ treadmilling did not affect FtsW and DivIB velocities or septum constriction rates. Contrarily, inhibition of PG synthesis slowed down or completely stopped both septum constriction and the directional movement of FtsW/PBP1 and DivIB. Our findings support a model for S. aureus in which a single population of processively moving FtsW/PBP1 remains associated with DivIB to drive cell constriction independently of treadmilling FtsZ filaments.
]]></description>
<dc:creator>Schaeper, S.</dc:creator>
<dc:creator>Brito, A. D.</dc:creator>
<dc:creator>Saraiva, B. M.</dc:creator>
<dc:creator>Squyres, G. R.</dc:creator>
<dc:creator>Holmes, M. J.</dc:creator>
<dc:creator>Garner, E. C.</dc:creator>
<dc:creator>Hensel, Z.</dc:creator>
<dc:creator>Henriques, R.</dc:creator>
<dc:creator>Pinho, M. G.</dc:creator>
<dc:date>2023-06-29</dc:date>
<dc:identifier>doi:10.1101/2023.06.29.547026</dc:identifier>
<dc:title><![CDATA[Processive movement of Staphylococcus aureus essential septal peptidoglycan synthases is independent of FtsZ treadmilling and drives cell constriction]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.28.546949v1?rss=1">
<title>
<![CDATA[
Quantitative assessment of single-cell RNA-seq clustering with CONCORDEX 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.28.546949v1?rss=1</link>
<description><![CDATA[
The rapid advancement of spatially resolved transcriptomics (SRT) technologies has facilitated exploration of how gene expression varies across tissues. However, identifying spatially variable genes remains challenging due to confounding variation introduced by the spatial distribution of cell types. We introduce a new approach to identifying spatial domains that are homogeneous with respect to cell-type composition that facilitates the decomposition of gene expression patterns by cell-type and spatial variation. Our method, called concordex, is efficient and effective across technological platforms and tissue types, and using several biological datasets we show that it can be used to identify genes with subtle variation patterns that are missed when considering only cell-type variation, or spatial variation, alone. The con-cordex tool is freely available at https://github.com/pachterlab/concordexR.
]]></description>
<dc:creator>Jackson, K. C.</dc:creator>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Galvez-Merchan, A.</dc:creator>
<dc:creator>Moses, L.</dc:creator>
<dc:creator>Chari, T.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2023-06-30</dc:date>
<dc:identifier>doi:10.1101/2023.06.28.546949</dc:identifier>
<dc:title><![CDATA[Quantitative assessment of single-cell RNA-seq clustering with CONCORDEX]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.06.29.547116v1?rss=1">
<title>
<![CDATA[
Machine learning reveals the control mechanics of the insect wing hinge 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.06.29.547116v1?rss=1</link>
<description><![CDATA[
Insects constitute the most species-rich radiation of metazoa, a success due to the evolution of active flight. Unlike pterosaurs, birds, and bats, the wings of insects did not evolve from legs1, but are novel structures attached to the body via a biomechanically complex hinge that transforms tiny, high-frequency oscillations of specialized power muscles into the sweeping back-and-forth motion of the wings2. The hinge consists of a system of tiny, hardened structures called sclerites that are interconnected to one another via flexible joints and regulated by the activity of specialized control muscles. Here, we imaged the activity of these muscles in a fly using a genetically encoded calcium indicator, while simultaneously tracking the 3D motion of the wings with high-speed cameras. Using machine learning approaches, we created a convolutional neural network3 that accurately predicts wing motion from the activity of the steering muscles, and an encoder-decoder4 that predicts the role of the individual sclerites on wing motion. By replaying patterns of wing motion on a dynamically scaled robotic fly, we quantified the effects of steering muscle activity on aerodynamic forces. A physics-based simulation that incorporates our model of the hinge generates flight maneuvers that are remarkably similar to those of free flying flies. This integrative, multi-disciplinary approach reveals the mechanical control logic of the insect wing hinge, arguably among the most sophisticated and evolutionarily important skeletal structures in the natural world.
]]></description>
<dc:creator>Melis, J. M.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:date>2023-06-30</dc:date>
<dc:identifier>doi:10.1101/2023.06.29.547116</dc:identifier>
<dc:title><![CDATA[Machine learning reveals the control mechanics of the insect wing hinge]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.01.546933v1?rss=1">
<title>
<![CDATA[
Configurational entropy is an intrinsic driver of tissue structural heterogeneity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.01.546933v1?rss=1</link>
<description><![CDATA[
Tissues comprise ordered arrangements of cells that can be surprisingly disordered in their details. How the properties of single cells and their microenvironment contribute to the balance between order and disorder at the tissue-scale remains poorly understood. Here, we address this question using the self-organization of human mammary organoids as a model. We find that organoids behave like a dynamic structural ensemble at the steady state. We apply a maximum entropy formalism to derive the ensemble distribution from three measurable parameters - the degeneracy of structural states, interfacial energy, and tissue activity (the energy associated with positional fluctuations). We link these parameters with the molecular and microenvironmental factors that control them to precisely engineer the ensemble across multiple conditions. Our analysis reveals that the entropy associated with structural degeneracy sets a theoretical limit to tissue order and provides new insight for tissue engineering, development, and our understanding of disease progression.
]]></description>
<dc:creator>Srivastava, V.</dc:creator>
<dc:creator>Hu, J. L.</dc:creator>
<dc:creator>Garbe, J. C.</dc:creator>
<dc:creator>Veytsman, B.</dc:creator>
<dc:creator>Shalabi, S. F.</dc:creator>
<dc:creator>Yllanes, D.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>LaBarge, M. A.</dc:creator>
<dc:creator>Huber, G.</dc:creator>
<dc:creator>Gartner, Z. J.</dc:creator>
<dc:date>2023-07-02</dc:date>
<dc:identifier>doi:10.1101/2023.07.01.546933</dc:identifier>
<dc:title><![CDATA[Configurational entropy is an intrinsic driver of tissue structural heterogeneity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.03.547549v1?rss=1">
<title>
<![CDATA[
Activity-Induced MeCP2 Phosphorylation Regulates Retinogeniculate Synapse Refinement 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.03.547549v1?rss=1</link>
<description><![CDATA[
Mutations in MECP2 give rise to Rett syndrome (RTT), an X-linked neurodevelopmental disorder that results in broad cognitive impairments in females. While the exact etiology of RTT symptoms remains unknown, one possible explanation for its clinical presentation is that loss of MeCP2 causes miswiring of neural circuits due to defects in the brains capacity to respond to changes in neuronal activity and sensory experience. Here we show that MeCP2 is phosphorylated at four residues in the brain (S86, S274, T308, and S421) in response to neuronal activity, and we generate a quadruple knock-in (QKI) mouse line in which all four activity-dependent sites are mutated to alanines to prevent phosphorylation. QKI mice do not display overt RTT phenotypes or detectable gene expression changes in two brain regions. However, electrophysiological recordings from the retinogeniculate synapse of QKI mice reveal that while synapse elimination is initially normal at P14, it is significantly compromised at P20. Notably, this phenotype is distinct from that previously reported for Mecp2 null mice, where synapses initially refine but then regress after the third postnatal week. We thus propose a model in which activity-induced phosphorylation of MeCP2 is critical for the proper timing of retinogeniculate synapse maturation specifically during the early postnatal period.

SIGNIFICANCE STATEMENTRett syndrome (RTT) is an X-linked neurodevelopmental disorder that predominantly affects girls. RTT is caused by loss of function mutations in a single gene MeCP2. Girls with RTT develop normally during their first year of life, but then experience neurological abnormalities including breathing and movement difficulties, loss of speech, and seizures. This study investigates the function of the MeCP2 protein in the brain, and how MeCP2 activity is modulated by sensory experience in early life. Evidence is presented that sensory experience affects MeCP2 function, and that this is required for synaptic pruning in the brain. These findings provide insight into MeCP2 function, and clues as to what goes awry in the brain when the function of MeCP2 is disrupted.
]]></description>
<dc:creator>Tzeng, C. P.</dc:creator>
<dc:creator>Whitwam, T.</dc:creator>
<dc:creator>Boxer, L. D.</dc:creator>
<dc:creator>Li, E.</dc:creator>
<dc:creator>Silberfeld, A.</dc:creator>
<dc:creator>Trowbridge, S.</dc:creator>
<dc:creator>Mei, K.</dc:creator>
<dc:creator>Lin, C.</dc:creator>
<dc:creator>Shamah, R.</dc:creator>
<dc:creator>Griffith, E. C.</dc:creator>
<dc:creator>Renthal, W.</dc:creator>
<dc:creator>Chen, C.</dc:creator>
<dc:creator>Greenberg, M. E.</dc:creator>
<dc:date>2023-07-03</dc:date>
<dc:identifier>doi:10.1101/2023.07.03.547549</dc:identifier>
<dc:title><![CDATA[Activity-Induced MeCP2 Phosphorylation Regulates Retinogeniculate Synapse Refinement]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.04.547724v1?rss=1">
<title>
<![CDATA[
Modeling the Correlation between Z and B in an X-ray Crystal Structure Refinement 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.04.547724v1?rss=1</link>
<description><![CDATA[
We have examined how the refined B-factor changes as a function of Z (the atomic number of a scatterer) at the sulfur site of the [4Fe:4S] cluster of the nitrogenase iron protein by refinement. A simple model is developed that quantitatively captures the observed relationship between Z and B, based on a Gaussian electron density distribution with a constant electron density at the position of the scatterer. From this analysis, the fractional changes in B and Z are found to be similar. The utility of B-factor refinement to potentially distinguish atom types reflects the Z dependence of X-ray atomic scattering factors; the weaker dependence of electron atomic scattering factors on Z implies that distinctions between refined values of B in an electron scattering structure will be less sensitive to the atomic identity of a scatterer than for the case with X-ray-diffraction. This behavior provides an example of the complementary information that can be extracted from different types of scattering studies.
]]></description>
<dc:creator>Buscagan, T. M.</dc:creator>
<dc:creator>Rees, D. C.</dc:creator>
<dc:date>2023-07-04</dc:date>
<dc:identifier>doi:10.1101/2023.07.04.547724</dc:identifier>
<dc:title><![CDATA[Modeling the Correlation between Z and B in an X-ray Crystal Structure Refinement]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.05.547767v1?rss=1">
<title>
<![CDATA[
Neural subspaces of imagined movements in parietal cortex remain stable over several years in humans. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.05.547767v1?rss=1</link>
<description><![CDATA[
A crucial goal in brain-machine interfacing is long-term stability of neural decoding performance, ideally without regular retraining. Here we demonstrate stable neural decoding over several years in two human participants, achieved by latent subspace alignment of multi-unit intracortical recordings in posterior parietal cortex. These results can be practically applied to significantly expand the longevity and generalizability of future movement decoding devices.
]]></description>
<dc:creator>Bashford, L.</dc:creator>
<dc:creator>Rosenthal, I. A.</dc:creator>
<dc:creator>Kellis, S.</dc:creator>
<dc:creator>Bjanes, D.</dc:creator>
<dc:creator>Pejsa, K.</dc:creator>
<dc:creator>Brunton, B. W.</dc:creator>
<dc:creator>Andersen, R.</dc:creator>
<dc:date>2023-07-07</dc:date>
<dc:identifier>doi:10.1101/2023.07.05.547767</dc:identifier>
<dc:title><![CDATA[Neural subspaces of imagined movements in parietal cortex remain stable over several years in humans.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.07.548143v1?rss=1">
<title>
<![CDATA[
Sea lamprey enlightens the origin of the coupling of retinoic acid signaling to vertebrate hindbrain segmentation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.07.548143v1?rss=1</link>
<description><![CDATA[
Retinoic acid (RA) is involved in antero-posterior patterning of the chordate body axis and, in jawed vertebrates, has been shown to play a major role at multiple levels of the gene regulatory network (GRN) regulating hindbrain segmentation. Knowing when and how RA became coupled to the core hindbrain GRN is important for understanding how ancient signaling pathways and patterning genes can evolve and generate diversity. Hence, we investigated the link between RA signaling and hindbrain segmentation in the sea lamprey Petromyzon marinus, an important jawless vertebrate model providing clues to decipher ancestral vertebrate features. Combining genomics, gene expression, and functional analyses of major components involved in RA synthesis (Aldh1as) and degradation (Cyp26s), we demonstrate that RA signaling is coupled to hindbrain segmentation in lamprey. Thus, the link between RA signaling and hindbrain segmentation is a pan vertebrate feature of the hindbrain and likely evolved at the base of vertebrates.
]]></description>
<dc:creator>Bedois, A.</dc:creator>
<dc:creator>Parker, H. J.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>Krumlauf, R.</dc:creator>
<dc:date>2023-07-07</dc:date>
<dc:identifier>doi:10.1101/2023.07.07.548143</dc:identifier>
<dc:title><![CDATA[Sea lamprey enlightens the origin of the coupling of retinoic acid signaling to vertebrate hindbrain segmentation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.17.549299v1?rss=1">
<title>
<![CDATA[
Conservation and divergence of regulatory architecture in nitrate-responsive plant gene circuits 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.17.549299v1?rss=1</link>
<description><![CDATA[
Nitrogen is an essential element for all life processes in plants. As such, plant roots dynamically respond to nitrogen availability below-ground by executing a signaling and transcriptional cascade resulting in altered plant growth, optimized for nutrient uptake. The NIN-LIKE PROTEIN 7 (NLP7) transcription factor senses nitrogen and along with its closely related paralog NLP6, partially coordinates these transcriptional responses. While post-translational regulation of NLP6/7 is well established, its upstream transcriptional regulation remains understudied in Arabidopsis and other plant species. Here, we dissect a previously identified sub-circuit upstream of NLP6/7 in Arabidopsis and which was predicted to contain multiple multi-node feedforward loops suggestive of an optimized design principle of nitrogen transcriptional regulation. This sub-circuit comprises AUXIN RESPONSE FACTOR 18 (ARF18), ARF9, DEHYDRATION RESPONSE ELEMENT BINDING-PROTEIN 26 (DREB26), A NAC-DOMAIN CONTAINING PROTEIN 32 (ANAC032), NLP6 and NLP7 and their regulation of NITRITE REDUCTASE 1 (NIR1). Conservation and divergence of this circuit and their influence on N-dependent root system architecture are similarly assessed in Solanum lycopersicum. The specific binding sites of these factors within their respective promoters and their putative cis-regulatory architecture are identified. The direct or indirect nature of these interactions are validated in planta. The resulting models were genetically validated in varying concentrations of available nitrate by measuring the transcriptional output of the network revealing rewiring of nitrogen regulation across distinct plant lineages.

Significance StatementNitrogen is a critical nutrient for plant growth and yield. While external N has facilitated modern agriculture, over-application of N-containing fertilizers has drastic ecological and environmental consequences. Here, we experimentally validate a six gene regulatory circuit with extensive feedforward loops identified to act upstream of the critical NIN-LIKE PROTEIN 6/7 transcription factors which regulates a nitrogen metabolic enzyme. Our results indicate conservation and divergence in these circuits between Arabidopsis and tomato despite the similar role of NLP7 in N-dependent changes in root system architecture. The resulting network models complement existing knowledge of NLP7 regulation by providing a framework for targeted transcriptional engineering to increase plant nitrogen use efficiency.
]]></description>
<dc:creator>Bian, C.</dc:creator>
<dc:creator>Demirer, G. S.</dc:creator>
<dc:creator>Oz, M. T.</dc:creator>
<dc:creator>Cai, Y.</dc:creator>
<dc:creator>Witham, S.</dc:creator>
<dc:creator>Mason, G. A.</dc:creator>
<dc:creator>Shen, R.</dc:creator>
<dc:creator>Ahn, J.</dc:creator>
<dc:creator>Gaudinier, A.</dc:creator>
<dc:creator>Brady, S.</dc:creator>
<dc:creator>Patron, N.</dc:creator>
<dc:date>2023-07-17</dc:date>
<dc:identifier>doi:10.1101/2023.07.17.549299</dc:identifier>
<dc:title><![CDATA[Conservation and divergence of regulatory architecture in nitrate-responsive plant gene circuits]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.20.549945v1?rss=1">
<title>
<![CDATA[
Voyager: exploratory single-cell genomics data analysis with geospatial statistics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.20.549945v1?rss=1</link>
<description><![CDATA[
Exploratory spatial data analysis (ESDA) can be a powerful approach to understanding single-cell genomics datasets, but it is not yet part of standard data analysis workflows. In particular, geospatial analyses, which have been developed and refined for decades, have yet to be fully adapted and applied to spatial single-cell analysis. We introduce the Voyager platform, which systematically brings the geospatial ESDA tradition to (spatial) -omics, with local, bivariate, and multivariate spatial methods not yet commonly applied to spatial -omics, united by a uniform user interface. Using Voyager, we showcase biological insights that can be derived with its methods, such as biologically relevant negative spatial autocorrelation. Underlying Voyager is the SpatialFeatureExperiment data structure, which combines Simple Feature with SingleCellExperiment and AnnData to represent and operate on geometries bundled with gene expression data. Voyager has comprehensive tutorials demonstrating ESDA built on GitHub Actions to ensure reproducibility and scalability, using data from popular commercial technologies. Voyager is implemented in both R/Bioconductor and Python/PyPI, and features compatibility tests to ensure that both implementations return consistent results.
]]></description>
<dc:creator>Moses, L.</dc:creator>
<dc:creator>Einarsson, P. H.</dc:creator>
<dc:creator>Jackson, K. C.</dc:creator>
<dc:creator>Luebbert, L.</dc:creator>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Antonsson, S. E.</dc:creator>
<dc:creator>Melsted, P.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2023-07-22</dc:date>
<dc:identifier>doi:10.1101/2023.07.20.549945</dc:identifier>
<dc:title><![CDATA[Voyager: exploratory single-cell genomics data analysis with geospatial statistics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.22.550181v1?rss=1">
<title>
<![CDATA[
Multiplex, quantitative, high-resolution imaging of protein:protein complexes via hybridization chain reaction 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.22.550181v1?rss=1</link>
<description><![CDATA[
Signal amplification based on the mechanism of hybridization chain reaction (HCR) facilitates spatial exploration of gene regulatory networks by enabling multiplex, quantitative, high-resolution imaging of RNA and protein targets. Here, we extend these capabilities to the imaging of protein:protein complexes, using proximity-dependent cooperative probes to conditionally generate a single amplified signal if and only if two target proteins are colocalized within the sample. HCR probes and amplifiers combine to provide automatic background suppression throughout the protocol, ensuring that even if reagents bind nonspecifically in the sample, they will not generate amplified background. We demonstrate protein:protein imaging with high signal-to-background in human cells, mouse proT cells, and highly autofluorescent formalin-fixed paraffin-embedded (FFPE) human breast tissue sections. Further, we demonstrate multiplex imaging of 3 different protein:protein complexes simultaneously and validate that HCR enables accurate and precise relative quantitation of protein:protein complexes with subcellular resolution in an anatomical context. Moreover, we establish a unified framework for simultaneous multiplex, quantitative, high-resolution imaging of RNA, protein, and protein:protein targets, with 1-step, isothermal, enzyme-free HCR signal amplification performed for all target classes simultaneously.



O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/550181v1_ufig1.gif" ALT="Figure 1">
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]]></description>
<dc:creator>Schulte, S. J.</dc:creator>
<dc:creator>Shin, B.</dc:creator>
<dc:creator>Rothenberg, E. V.</dc:creator>
<dc:creator>Pierce, N. A.</dc:creator>
<dc:date>2023-07-23</dc:date>
<dc:identifier>doi:10.1101/2023.07.22.550181</dc:identifier>
<dc:title><![CDATA[Multiplex, quantitative, high-resolution imaging of protein:protein complexes via hybridization chain reaction]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.21.550102v1?rss=1">
<title>
<![CDATA[
Computational and neural mechanisms underlying the influence of action affordances on value-based choice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.21.550102v1?rss=1</link>
<description><![CDATA[
When encountering a novel situation, an intelligent agent needs to find out which actions are most beneficial for interacting with that environment. One purported mechanism for narrowing down the scope of possible actions is the concept of action affordance. Here, we delve into the neuro-computational mechanisms accounting for how action affordance shapes value-based learning in a novel environment by utilizing a novel task alongside computational modeling of behavioral and fMRI data collected in humans. Our findings indicate that rather than simply exerting an initial or persistent bias on value-driven choices, action affordance is better conceived of as an independent system that concurrently guides action-selection alongside value-based decision-making. These two systems engage in a competitive process to determine final action selection, governed by a dynamic meta controller. We find that the pre-supplementary motor area and anterior cingulate cortex plays a central role in exerting meta-control over the two systems while the posterior parietal cortex integrates the predictions from these two controllers of what action to select, so that the action-selection process dynamically takes into account both the expected value and appropriateness of particular actions for a given scenario.
]]></description>
<dc:creator>Yi, S.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:date>2023-07-25</dc:date>
<dc:identifier>doi:10.1101/2023.07.21.550102</dc:identifier>
<dc:title><![CDATA[Computational and neural mechanisms underlying the influence of action affordances on value-based choice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.24.550434v1?rss=1">
<title>
<![CDATA[
Gas vesicle-blood interactions enhance ultrasound imaging contrast 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.24.550434v1?rss=1</link>
<description><![CDATA[
Gas vesicles (GVs) are genetically encoded, air-filled protein nanostructures of broad interest for biomedical research and clinical applications, acting as imaging and therapeutic agents for ultrasound, magnetic resonance, and optical techniques. However, the biomedical applications of GVs as a systemically injectable nanomaterial have been hindered by a lack of understanding of GVs interactions with blood components, which can significantly impact in vivo performance. Here, we investigate the dynamics of GVs in the bloodstream using a combination of ultrasound and optical imaging, surface functionalization, flow cytometry, and mass spectrometry. We find that erythrocytes and serum proteins bind to GVs and shape their acoustic response, circulation time, and immunogenicity. We show that by modifying the GV surface, we can alter these interactions and thereby modify GVs in vivo performance. These results provide critical insights for the development of GVs as agents for nanomedicine.
]]></description>
<dc:creator>Ling, B.</dc:creator>
<dc:creator>Ko, J. H.</dc:creator>
<dc:creator>Stordy, B.</dc:creator>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Didden, T. F.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Swift, M. B.</dc:creator>
<dc:creator>Chan, W. C. W.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2023-07-25</dc:date>
<dc:identifier>doi:10.1101/2023.07.24.550434</dc:identifier>
<dc:title><![CDATA[Gas vesicle-blood interactions enhance ultrasound imaging contrast]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.25.550544v1?rss=1">
<title>
<![CDATA[
Pseudomonas aeruginosa AlgF is a protein-protein interaction mediator required for acetylation of the alginate exopolysaccharide 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.25.550544v1?rss=1</link>
<description><![CDATA[
Enzymatic modifications of bacterial exopolysaccharides enhance immune evasion and persistence during infection. In the Gram-negative opportunistic pathogen Pseudomonas aeruginosa, acetylation of alginate reduces opsonic killing by phagocytes and improves reactive oxygen species scavenging. Although it is well-known that alginate acetylation in P. aeruginosa requires AlgI, AlgJ, AlgF, and AlgX, how these proteins coordinate polymer modification at a molecular level remains unclear. Here, we describe the structural characterization of AlgF and its protein interaction network. We characterize direct interactions between AlgF and both AlgJ and AlgX in vitro, and demonstrate an association between AlgF and AlgX, as well as AlgJ and AlgI, in P. aeruginosa. We determine that AlgF does not exhibit acetylesterase activity and is unable to bind to polymannuronate in vitro. Therefore, we propose that AlgF functions to mediate protein-protein interactions between alginate acetylation enzymes, forming the periplasmic AlgJFXK (AlgJ-AlgF-AlgX-AlgK) acetylation and export complex required for robust biofilm formation.
]]></description>
<dc:creator>Low, K.</dc:creator>
<dc:creator>Gheorghita, A. A.</dc:creator>
<dc:creator>Tammam, S.</dc:creator>
<dc:creator>Whitfield, G. B.</dc:creator>
<dc:creator>Li, Y. E.</dc:creator>
<dc:creator>Riley, L. M.</dc:creator>
<dc:creator>Weadge, J.</dc:creator>
<dc:creator>Caldwell, S.</dc:creator>
<dc:creator>Chong, P. A.</dc:creator>
<dc:creator>Walvoort, M.</dc:creator>
<dc:creator>Kitova, E.</dc:creator>
<dc:creator>Klassen, J.</dc:creator>
<dc:creator>Howell, P. L.</dc:creator>
<dc:date>2023-07-25</dc:date>
<dc:identifier>doi:10.1101/2023.07.25.550544</dc:identifier>
<dc:title><![CDATA[Pseudomonas aeruginosa AlgF is a protein-protein interaction mediator required for acetylation of the alginate exopolysaccharide]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.25.550582v1?rss=1">
<title>
<![CDATA[
Systematic assessment of long-read RNA-seq methods for transcript identification and quantification 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.25.550582v1?rss=1</link>
<description><![CDATA[
AbstractThe Long-read RNA-Seq Genome Annotation Assessment Project (LRGASP) Consortium was formed to evaluate the effectiveness of long-read approaches for transcriptome analysis. The consortium generated over 427 million long-read sequences from cDNA and direct RNA datasets, encompassing human, mouse, and manatee species, using different protocols and sequencing platforms. These data were utilized by developers to address challenges in transcript isoform detection and quantification, as well as de novo transcript isoform identification. The study revealed that libraries with longer, more accurate sequences produce more accurate transcripts than those with increased read depth, whereas greater read depth improved quantification accuracy. In well-annotated genomes, tools based on reference sequences demonstrated the best performance. When aiming to detect rare and novel transcripts or when using reference-free approaches, incorporating additional orthogonal data and replicate samples are advised. This collaborative study offers a benchmark for current practices and provides direction for future method development in transcriptome analysis.
]]></description>
<dc:creator>Pardo-Palacios, F. J.</dc:creator>
<dc:creator>Wang, D.</dc:creator>
<dc:creator>Reese, F.</dc:creator>
<dc:creator>Diekhans, M.</dc:creator>
<dc:creator>Carbonell-Sala, S.</dc:creator>
<dc:creator>Williams, B.</dc:creator>
<dc:creator>Loveland, J. E.</dc:creator>
<dc:creator>De Maria, M.</dc:creator>
<dc:creator>Adams, M. S.</dc:creator>
<dc:creator>Balderrama-Gutierrez, G.</dc:creator>
<dc:creator>Behera, A. K.</dc:creator>
<dc:creator>Gonzalez, J. M.</dc:creator>
<dc:creator>Hunt, T.</dc:creator>
<dc:creator>Lagarde, J.</dc:creator>
<dc:creator>Liang, C. E.</dc:creator>
<dc:creator>Li, H.</dc:creator>
<dc:creator>Meade, M. J.</dc:creator>
<dc:creator>Amador, D. A. M.</dc:creator>
<dc:creator>Prjibelski, A. D.</dc:creator>
<dc:creator>Birol, I.</dc:creator>
<dc:creator>Bostan, H.</dc:creator>
<dc:creator>Brooks, A. M.</dc:creator>
<dc:creator>Celik, M. H.</dc:creator>
<dc:creator>Chen, Y.</dc:creator>
<dc:creator>Du, M. R. M.</dc:creator>
<dc:creator>Felton, C.</dc:creator>
<dc:creator>Goke, J.</dc:creator>
<dc:creator>Hafezqorani, S.</dc:creator>
<dc:creator>Herwig, R.</dc:creator>
<dc:creator>Kawaji, H.</dc:creator>
<dc:creator>Lee, J.</dc:creator>
<dc:creator>Li, J.-L.</dc:creator>
<dc:creator>Lienhard, M.</dc:creator>
<dc:creator>Mikheenko, A.</dc:creator>
<dc:creator>Mulligan, D.</dc:creator>
<dc:creator>Nip, K. M.</dc:creator>
<dc:creator>Pertea, M.</dc:creator>
<dc:creator>Ritchie, M. E.</dc:creator>
<dc:creator>Sim, A. D.</dc:creator>
<dc:creator>Tang, A. D.</dc:creator>
<dc:creator>Wan, Y. K.</dc:creator>
<dc:creator>Wang, C.</dc:creator>
<dc:creator>Wong, B. Y.</dc:creator>
<dc:creator>Yang, C</dc:creator>
<dc:date>2023-07-27</dc:date>
<dc:identifier>doi:10.1101/2023.07.25.550582</dc:identifier>
<dc:title><![CDATA[Systematic assessment of long-read RNA-seq methods for transcript identification and quantification]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.07.28.551057v1?rss=1">
<title>
<![CDATA[
Unraveling cell differentiation mechanisms through topological exploration of single-cell developmental trajectories 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.07.28.551057v1?rss=1</link>
<description><![CDATA[
Understanding the circuits that control cell differentiation is a fundamental problem in developmental biology. Single-cell RNA sequencing has emerged as a powerful tool for investigating this problem. However, the reconstruction of developmental trajectories is based on the assumption that cell states traverse a tree-like structure, which may bias our understanding of critical developmental mechanisms. To address this limitation, we developed a framework, TopGen, that enables identifying topological signatures of functional biological circuits as persistent homology groups in transcriptome space. First, we show that TopGen can identify genetic drivers of topological structures in simulated datasets. We then applied our approach to more than ten single-cell developmental atlases and found that topological transcriptome spaces are predominantly path-connected and only sometimes simply connected. Finally, we applied TopGen to analyze gene expression patterns in topological loops representing stem-like, transdifferentiation, and convergent cell circuits, found in C. elegans, H. vulgaris, and N. vectensis, respectively. Our results show that some essential differentiation mechanisms use non-trivial topological motifs, and that these motifs can be conserved in a cell-type-specific manner. Thus, our approach to studying the topological properties of developmental transcriptome atlases opens new possibilities for understanding cell development and differentiation.
]]></description>
<dc:creator>Flores-Bautista, E.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2023-07-30</dc:date>
<dc:identifier>doi:10.1101/2023.07.28.551057</dc:identifier>
<dc:title><![CDATA[Unraveling cell differentiation mechanisms through topological exploration of single-cell developmental trajectories]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.01.551478v1?rss=1">
<title>
<![CDATA[
A feedback control mechanism governs the synthesis of lipid-linked precursors of the bacterial cell wall 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.01.551478v1?rss=1</link>
<description><![CDATA[
Many bacterial surface glycans such as the peptidoglycan (PG) cell wall, O-antigens, and capsules are built from monomeric units linked to a polyprenyl lipid carrier. How this limiting lipid carrier is effectively distributed among competing pathways has remained unclear for some time. Here, we describe the isolation and characterization of hyperactive variants of Pseudomonas aeruginosa MraY, the essential and conserved enzyme catalyzing the formation of the first lipid-linked PG precursor called lipid I. These variants result in the elevated production of the final PG precursor lipid II in cells and are hyperactive in a purified system. Amino acid substitutions within the activated MraY variants unexpectedly map to a cavity on the extracellular side of the dimer interface, far from the active site. Our structural evidence and molecular dynamics simulations suggest that the cavity is a binding site for lipid II molecules that have been transported to the outer leaflet of the membrane. Overall, our results support a model in which excess externalized lipid II allosterically inhibits MraY, providing a feedback mechanism to prevent the sequestration of lipid carrier in the PG biogenesis pathway. MraY belongs to the broadly distributed polyprenyl-phosphate N-acetylhexosamine 1-phosphate transferase (PNPT) superfamily of enzymes. We therefore propose that similar feedback mechanisms may be widely employed to coordinate precursor supply with demand by polymerases, thereby optimizing the partitioning of lipid carriers between competing glycan biogenesis pathways.
]]></description>
<dc:creator>Marmont, L. S.</dc:creator>
<dc:creator>Orta, A. K.</dc:creator>
<dc:creator>Corey, R. A.</dc:creator>
<dc:creator>Sychantha, D.</dc:creator>
<dc:creator>Fernandez-Galliano, A.</dc:creator>
<dc:creator>Li, Y. E.</dc:creator>
<dc:creator>Baileeves, B. W.</dc:creator>
<dc:creator>Greene, N. G.</dc:creator>
<dc:creator>Stansfeld, P. J.</dc:creator>
<dc:creator>Clemons, W. M.</dc:creator>
<dc:creator>Bernhardt, T. G.</dc:creator>
<dc:date>2023-08-01</dc:date>
<dc:identifier>doi:10.1101/2023.08.01.551478</dc:identifier>
<dc:title><![CDATA[A feedback control mechanism governs the synthesis of lipid-linked precursors of the bacterial cell wall]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.04.552070v1?rss=1">
<title>
<![CDATA[
Functional potential and evolutionary response to long-term heat selection of bacterial associates of coral photosymbionts 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.04.552070v1?rss=1</link>
<description><![CDATA[
Corals rely on a wide range of microorganisms for their functioning, including intracellular dinoflagellates (Symbiodiniaceae) and bacteria. Marine heatwaves trigger the loss of Symbiodiniaceae from coral tissues - coral bleaching - often leading to death. While coral-bacteria interactions are widely studied, Symbiodiniaceae-bacteria interactions have remained largely uninvestigated. Here, we provide a genomic analysis of 49 bacteria, spanning 16 genera, that closely associate with six cultured Symbiodiniaceae species. We analyzed bacterial functional potential by focusing on potentially beneficial functions for the Symbiodiniaceae host, including B vitamin synthesis and antioxidant abilities, which may be crucial for Symbiodiniaceae heat tolerance and in turn coral resistance to thermal bleaching. These analyses suggest a wide potential for B vitamin synthesis and the scavenging of reactive oxygen species (through the production of carotenoids or antioxidant enzymes), and possibly the transfer of organic carbon to host cells. Single nucleotide polymorphism analysis between bacteria isolated from wild-type and heat-evolved Symbiodiniaceae cultures revealed that exposure to long-term elevated temperature has resulted in mutations in genes known to be involved in host-symbiont interactions, such as secretion systems. Climate change may therefore modify how Symbiodiniaceae and bacteria interact. This study provides an overview of the possible roles of Symbiodiniaceae-associated bacteria in Symbiodiniaceae functioning and heat tolerance, reinforcing the need for further studies of such interactions to fully understand coral biology and climate resilience.

ImportanceSymbiotic microorganisms are crucial for the survival of corals and their resistance to coral bleaching in the face of climate change. However, the impact of microbe-microbe interactions on coral functioning is mostly unknown, but could be essential factors for coral adaption to future climates. Here, we investigated interactions between cultured dinoflagellates of the Symbiodiniaceae family, essential photosymbionts of corals, and associated bacteria. By assessing the genomic potential of 49 bacteria, we found that they are likely beneficial for Symbiodiniaceae, through the production of B vitamins and antioxidants. Additionally, bacterial genes involved in host-symbiont interactions, such as secretion systems, accumulated mutations following long-term exposure to heat, suggesting symbiotic interactions may change under climate change. This highlights the importance of microbe-microbe interactions in coral functioning.
]]></description>
<dc:creator>Maire, J.</dc:creator>
<dc:creator>Philip, G. K.</dc:creator>
<dc:creator>Livingston, J.</dc:creator>
<dc:creator>Judd, L. M.</dc:creator>
<dc:creator>Blackall, L.</dc:creator>
<dc:creator>van Oppen, M.</dc:creator>
<dc:date>2023-08-04</dc:date>
<dc:identifier>doi:10.1101/2023.08.04.552070</dc:identifier>
<dc:title><![CDATA[Functional potential and evolutionary response to long-term heat selection of bacterial associates of coral photosymbionts]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.07.552387v1?rss=1">
<title>
<![CDATA[
EasyFlow: An open source, user friendly cytometry analyzer with graphic user interface (GUI) 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.07.552387v1?rss=1</link>
<description><![CDATA[
Flow cytometry enables quantitative measurements of fluorescence in single cells. The technique was widely used for immunology to identify populations with different surface protein markers. More recently, the usage of flow cytometry has been extended to additional readouts, including intracellular proteins and fluorescent protein transgenes, and is widely utilized to study development, systems biology, microbiology, and many other fields. A common file format (FCS format, defined by International Society for Advancement of Cytometry (ISAC)) has been universally adopted, facilitating data exchange between different machines. A diverse spectrum of software packages have been developed for analysis of flow cytometry data. However, those are either 1) costly proprietary softwares, 2) open source packages with prerequisite installation of R or Python and sometimes require users to have experience in coding or 3) online tools that are limiting for analysis of large data sets. Here we present EasyFlow, an open source flow cytometry analysis GUI based on Matlab or Python, that can be installed and run locally cross-platform-ly (Windows and MacOS), without prerequisite user having previous knowledge on coding. The python version (EasyFlowQ) is also developed on a popular plotting framework (Matplotlib) and modern user interface (UI) toolkit (Qt), allowing more advanced users to customize and keep contributing to the software, as well as its tutorials. Overall, EasyFlow serves as a simple-to-use tool for inexperienced users with little coding experience to use locally, as well as a platform for advanced users to further customize for their own needs.
]]></description>
<dc:creator>Ma, Y.</dc:creator>
<dc:creator>Antebi, Y.</dc:creator>
<dc:date>2023-08-09</dc:date>
<dc:identifier>doi:10.1101/2023.08.07.552387</dc:identifier>
<dc:title><![CDATA[EasyFlow: An open source, user friendly cytometry analyzer with graphic user interface (GUI)]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.08.552427v1?rss=1">
<title>
<![CDATA[
An evolutionary timescale for Bacteria calibrated using the Great Oxidation Event 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.08.552427v1?rss=1</link>
<description><![CDATA[
Most of lifes diversity and history is microbial but it has left a meagre fossil record, greatly hindering understanding of evolution in deep time. However, the co-evolution of life and the Earth system has left signatures of bacterial metabolism in the geochemical record, most conspicuously the Great Oxidation Event (GOE) [~]2.33 billion years ago (Ga, (Poulton et al. 2021)), in which oxygenic photosynthesis and tectonism (Eguchi, Seales, and Dasgupta 2019) transformed Earths biosphere from dominantly anaerobic to aerobic. Here, we combine machine learning and phylogenetic reconciliation to infer ancestral transitions to aerobic lifestyles during bacterial evolution. Linking these transitions to the GOE provides new constraints to infer the timetree of Bacteria. We find that extant bacterial phyla are truly ancient, having radiated in the Archaean and the Proterozoic: the oldest include Bacillota (Firmicutes), which radiated 3.1-3.7 Ga, Cyanobacteria (3.3-3.5 Ga) and Patescibacteria (3-3.5 Ga). We show that most bacterial phyla were ancestrally anaerobic and that most transitions to an aerobic lifestyle post-dated the GOE. Our analyses trace oxygen production and consumption back to Cyanobacteria. From that starting point, horizontal transfer seeded aerobic lifestyles across bacterial diversity over hundreds of millions of years. Our analyses demonstrate that the diversification of aerobes proceeded in two waves corresponding to the GOE and to a second sustained rise in atmospheric O2 at the dawn of the Palezoic (Krause et al. 2022).
]]></description>
<dc:creator>Davin, A. A.</dc:creator>
<dc:creator>Woodcroft, B. J.</dc:creator>
<dc:creator>Soo, R. M.</dc:creator>
<dc:creator>Murali, R.</dc:creator>
<dc:creator>Schrempf, D.</dc:creator>
<dc:creator>Clark, J.</dc:creator>
<dc:creator>Boussau, B.</dc:creator>
<dc:creator>Moody, E. R. R.</dc:creator>
<dc:creator>Szantho, L. L.</dc:creator>
<dc:creator>Richy, E.</dc:creator>
<dc:creator>Pisani, D.</dc:creator>
<dc:creator>Hemp, J.</dc:creator>
<dc:creator>Fischer, W. W.</dc:creator>
<dc:creator>Donoghue, P.</dc:creator>
<dc:creator>Spang, A.</dc:creator>
<dc:creator>Hugenholtz, P.</dc:creator>
<dc:creator>Williams, T. A.</dc:creator>
<dc:creator>Szöllosi, G. J.</dc:creator>
<dc:date>2023-08-11</dc:date>
<dc:identifier>doi:10.1101/2023.08.08.552427</dc:identifier>
<dc:title><![CDATA[An evolutionary timescale for Bacteria calibrated using the Great Oxidation Event]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.10.552770v1?rss=1">
<title>
<![CDATA[
Sphingolipid metabolism is spatially regulated in the developing embryo by SOXE genes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.10.552770v1?rss=1</link>
<description><![CDATA[
During epithelial-to-mesenchymal transition (EMT), significant rearrangements occur in plasma membrane protein and lipid content that are important for membrane function and acquisition of cell motility. To gain insight into how neural crest cells regulate their lipid content at the transcriptional level during EMT, here we identify critical enhancer sequences that regulate the expression of SMPD3, a gene responsible for sphingomyelin hydrolysis to produce ceramide, which is necessary for neural crest EMT. We uncovered three enhancer regions within the first intron of the SMPD3 locus that drive reporter expression in distinct spatial and temporal domains, together collectively recapitulating the expression domains of endogenous SMPD3 within the ectodermal lineages. We further dissected one enhancer that is specifically active in the migrating neural crest. By mutating putative transcriptional input sites or knocking down upstream regulators, we find that the SoxE-family transcription factors Sox9 and Sox10 regulate the expression of SMPD3 in migrating neural crest cells. Together these results shed light on how core components of developmental gene regulatory networks interact with metabolic effector genes to control changes in membrane lipid content.

HighlightsO_LISMPD3 is expressed in the neural tube, neural crest, and notochord during early development
C_LIO_LISMPD3 expression is regulated by at least three intronic enhancers
C_LIO_LISox10 and its binding sites are required for expression by a migratory neural crest-specific SMPD3 enhancer
C_LIO_LISox10 is a positive regulator of endogenous SMPD3 expression during neural crest migration
C_LI
]]></description>
<dc:creator>Piacentino, M. L.</dc:creator>
<dc:creator>Fasse, A. J.</dc:creator>
<dc:creator>Camacho-Avila, A.</dc:creator>
<dc:creator>Grabylnikov, I.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:date>2023-08-11</dc:date>
<dc:identifier>doi:10.1101/2023.08.10.552770</dc:identifier>
<dc:title><![CDATA[Sphingolipid metabolism is spatially regulated in the developing embryo by SOXE genes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.14.553301v1?rss=1">
<title>
<![CDATA[
A chemical reaction network model of PURE 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.14.553301v1?rss=1</link>
<description><![CDATA[
Cell-free expression systems provide a method for rapid DNA circuit prototyping and functional protein synthesis. While crude extracts remain a black box with many components carrying out unknown reactions, the PURE system contains only the required transcription and translation components for protein production. All proteins and small molecules are at known concentrations, opening up the possibility of detailed modeling for reliable computational predictions. However, there is little to no experimental data supporting the expression of target proteins for detailed protein models PURE models. In this work, we build a chemical reaction network transcription model for PURE protein synthesis. We compare the transcription models using DNA encoding for the malachite-green aptamer (MGapt) to measure mRNA production. Furthermore, we expand the PURE detailed translation model for an arbitrary set of amino acids and length. Lastly, we combine the transcription and the expanded translation models to create a PURE protein synthesis model built purely from mass-action reactions. We use the combined model to capture the translation of a plasmid encoding MGapt and deGFP under a T7-promoter and a strong RBS. The model accurately predicts the MGapt mRNA production for the first two hours, the dynamics of deGFP expression, and the total protein production with an accuracy within 10 %.
]]></description>
<dc:creator>Jurado, Z.</dc:creator>
<dc:creator>Pandey, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2023-08-14</dc:date>
<dc:identifier>doi:10.1101/2023.08.14.553301</dc:identifier>
<dc:title><![CDATA[A chemical reaction network model of PURE]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.14.553299v1?rss=1">
<title>
<![CDATA[
Projection neurons are necessary for the maintenance, but not for the assembly, of the mouse olfactory circuit 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.14.553299v1?rss=1</link>
<description><![CDATA[
The assembly and maintenance of neural circuits is crucial for proper brain function. Although the assembly of brain circuits has been extensively studied, much less is understood about the mechanisms controlling their maintenance as animals mature. In the olfactory system, the axons of olfactory sensory neurons (OSNs) expressing the same odor receptor converge into discrete synaptic structures of the olfactory bulb (OB) called glomeruli, forming a stereotypic odor map. The OB projection neurons, called mitral and tufted cells (M/Ts), have a single dendrite that branches into a single glomerulus, where they make synapses with OSNs. We used a genetic method to progressively eliminate the vast majority of M/T cells in early postnatal mice, and observed that the assembly of the OB bulb circuits proceeded normally. However, as the animals became adults the apical dendrite of remaining M/Ts grew multiple branches that innervated several glomeruli, and OSNs expressing single odor receptors projected their axons into multiple glomeruli, disrupting the olfactory sensory map. Moreover, ablating the M/Ts in adult animals also resulted in similar structural changes in the projections of remaining M/Ts and axons from OSNs. Interestingly, the ability of these mice to detect odors was relatively preserved despite only having 1-5% of projection neurons transmitting odorant information to the brain, and having highly disrupted circuits in the OB. These results indicate that a reduced number of projection neurons does not affect the normal assembly of the olfactory circuit, but induces structural instability of the olfactory circuitry of adult animals.
]]></description>
<dc:creator>Sanchez-Guardado, L.</dc:creator>
<dc:creator>Razavi, P.</dc:creator>
<dc:creator>Wang, B.</dc:creator>
<dc:creator>Callejas-Marin, A.</dc:creator>
<dc:creator>Lois, C.</dc:creator>
<dc:date>2023-08-15</dc:date>
<dc:identifier>doi:10.1101/2023.08.14.553299</dc:identifier>
<dc:title><![CDATA[Projection neurons are necessary for the maintenance, but not for the assembly, of the mouse olfactory circuit]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.15.553460v1?rss=1">
<title>
<![CDATA[
Changes in an Enzyme Ensemble During Catalysis Observed by High Resolution XFEL Crystallography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.15.553460v1?rss=1</link>
<description><![CDATA[
Enzymes populate ensembles of structures with intrinsically different catalytic proficiencies that are difficult to experimentally characterize. We use time-resolved mix-and-inject serial crystallography (MISC) at an X-ray free electron laser (XFEL) to observe catalysis in a designed mutant (G150T) isocyanide hydratase (ICH) enzyme that enhances sampling of important minor conformations. The active site exists in a mixture of conformations and formation of the thioimidate catalytic intermediate selects for catalytically competent substates. A prior proposal for active site cysteine charge-coupled conformational changes in ICH is validated by determining structures of the enzyme over a range of pH values. A combination of large molecular dynamics simulations of the enzyme in crystallo and time-resolved electron density maps shows that ionization of the general acid Asp17 during catalysis causes additional conformational changes that propagate across the dimer interface, connecting the two active sites. These ionization-linked changes in the ICH conformational ensemble permit water to enter the active site in a location that is poised for intermediate hydrolysis. ICH exhibits a tight coupling between ionization of active site residues and catalysis-activated protein motions, exemplifying a mechanism of electrostatic control of enzyme dynamics.
]]></description>
<dc:creator>Smith, N.</dc:creator>
<dc:creator>Dasgupta, M.</dc:creator>
<dc:creator>Wych, D. C.</dc:creator>
<dc:creator>Dolamore, C.</dc:creator>
<dc:creator>Sierra, R. G.</dc:creator>
<dc:creator>Lisova, S.</dc:creator>
<dc:creator>Marchany-Rivera, D.</dc:creator>
<dc:creator>Cohen, A. E.</dc:creator>
<dc:creator>Boutet, S.</dc:creator>
<dc:creator>Hunter, M. S.</dc:creator>
<dc:creator>Kupitz, C.</dc:creator>
<dc:creator>Poitevin, F.</dc:creator>
<dc:creator>Moss, F. R.</dc:creator>
<dc:creator>Brewster, A. S.</dc:creator>
<dc:creator>Sauter, N. K.</dc:creator>
<dc:creator>Young, I. D.</dc:creator>
<dc:creator>Wolff, A. M.</dc:creator>
<dc:creator>Tiwari, V. K.</dc:creator>
<dc:creator>Kumar, N.</dc:creator>
<dc:creator>Berkowitz, D. B.</dc:creator>
<dc:creator>Hadt, R. G.</dc:creator>
<dc:creator>Thompson, M. C.</dc:creator>
<dc:creator>Follmer, A. H.</dc:creator>
<dc:creator>Wall, M. E.</dc:creator>
<dc:creator>Wilson, M. A.</dc:creator>
<dc:date>2023-08-16</dc:date>
<dc:identifier>doi:10.1101/2023.08.15.553460</dc:identifier>
<dc:title><![CDATA[Changes in an Enzyme Ensemble During Catalysis Observed by High Resolution XFEL Crystallography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.16.553624v1?rss=1">
<title>
<![CDATA[
Triaging of -helical proteins to the mitochondrial outer membrane by distinct chaperone machinery based on substrate topology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.16.553624v1?rss=1</link>
<description><![CDATA[
Mitochondrial outer membrane -helical proteins play critical roles in mitochondrial-cytoplasmic communication, but the rules governing the targeting and insertion of these biophysically diverse substrates remain unknown. Here, we first defined the complement of required mammalian biogenesis machinery through genome-wide CRISPRi screens using topologically distinct membrane proteins. Systematic analysis of nine identified factors across 21 diverse -helical substrates reveals that these components are organized into distinct targeting pathways which act on substrates based on their topology. NAC is required for efficient targeting of polytopic proteins whereas signal-anchored proteins require TTC1, a novel cytosolic chaperone which physically engages substrates. Biochemical and mutational studies reveal that TTC1 employs a conserved TPR domain and a hydrophobic groove in its C-terminal domain to support substrate solubilization and insertion into mitochondria. Thus, targeting of diverse mitochondrial membrane proteins is achieved through topological triaging in the cytosol using principles with similarities to ER membrane protein biogenesis systems.
]]></description>
<dc:creator>Muthukumar, G.</dc:creator>
<dc:creator>Stevens, T. A.</dc:creator>
<dc:creator>Inglis, A. J.</dc:creator>
<dc:creator>Esantsi, T. K.</dc:creator>
<dc:creator>Saunders, R. A.</dc:creator>
<dc:creator>Schulte, F.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:creator>Guna, A.</dc:creator>
<dc:creator>Weissman, J. S.</dc:creator>
<dc:date>2023-08-17</dc:date>
<dc:identifier>doi:10.1101/2023.08.16.553624</dc:identifier>
<dc:title><![CDATA[Triaging of -helical proteins to the mitochondrial outer membrane by distinct chaperone machinery based on substrate topology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.17.552973v1?rss=1">
<title>
<![CDATA[
Intracellular Pseudomonas aeruginosa within the airway epithelium of Cystic Fibrosis lung tissues 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.17.552973v1?rss=1</link>
<description><![CDATA[
RATIONALEPseudomonas aeruginosa (P.a.) is the major bacterial pathogen colonizing the airways of adult cystic fibrosis (CF) patients and causes chronic infections that persist despite antibiotic therapy. Intracellular bacteria may represent an unrecognized reservoir of bacteria that evades the immune system and antibiotic therapy. While the ability of P.a. to invade and survive within epithelial cells has been described in vitro in different epithelial cell models, evidence of this intracellular lifestyle in human lung tissues is currently lacking.

OBJECTIVESTo detect and characterize intracellular P.a. in CF airway epithelium from human lung explant tissues.

METHODSWe sampled the lung explant tissues from CF and non-CF patients undergoing lung transplantation and analyzed lung tissue sections for the presence of intracellular P.a. by quantitative culture and microscopy, in parallel to histopathology and airway morphometry.

MEASUREMENTS AND MAIN RESULTSP.a. was isolated from the lungs of 7 CF patients undergoing lung transplantation. Microscopic assessment revealed the presence of intracellular P.a. within airway epithelial cells in 3 out of the 7 lungs analyzed, at a varying but rare frequency. We observed those events occurring in lung regions with high bacterial burden.

CONCLUSIONThis is the first study describing the presence of intracellular P.a. in CF lung tissues. While intracellular P.a. in airway epithelial cells are likely relatively rare events, our findings highlight the plausible occurrence of this intracellular bacterial reservoir in chronic CF infections.
]]></description>
<dc:creator>Malet, J. K.</dc:creator>
<dc:creator>Faure, E.</dc:creator>
<dc:creator>Adam, D.</dc:creator>
<dc:creator>Donner, J.</dc:creator>
<dc:creator>Liu, L.</dc:creator>
<dc:creator>Pilon, S.-J.</dc:creator>
<dc:creator>Fraser, R.</dc:creator>
<dc:creator>Jorth, P.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:creator>Brochiero, E.</dc:creator>
<dc:creator>Rousseau, S.</dc:creator>
<dc:creator>Nguyen, D.</dc:creator>
<dc:date>2023-08-17</dc:date>
<dc:identifier>doi:10.1101/2023.08.17.552973</dc:identifier>
<dc:title><![CDATA[Intracellular Pseudomonas aeruginosa within the airway epithelium of Cystic Fibrosis lung tissues]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.19.553321v1?rss=1">
<title>
<![CDATA[
Designed Endocytosis-Triggering Proteins mediate Targeted Degradation and amplify signaling 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.19.553321v1?rss=1</link>
<description><![CDATA[
Endocytosis and lysosomal trafficking of cell surface receptors can be triggered by interaction with endogenous ligands. Therapeutic approaches such as LYTAC1,2 and KineTAC3, have taken advantage of this to target specific proteins for degradation by fusing modified native ligands to target binding proteins. While powerful, these approaches can be limited by possible competition with the endogenous ligand(s), the requirement in some cases for chemical modification that limits genetic encodability and can complicate manufacturing, and more generally, there may not be natural ligands which stimulate endocytosis through a given receptor. Here we describe general protein design approaches for designing endocytosis triggering binding proteins (EndoTags) that overcome these challenges. We present EndoTags for the IGF-2R, ASGPR, Sortillin, and Transferrin receptors, and show that fusing these tags to proteins which bind to soluble or transmembrane protein leads to lysosomal trafficking and target degradation; as these receptors have different tissue distributions, the different EndoTags could enable targeting of degradation to different tissues. The modularity and genetic encodability of EndoTags enables AND gate control for higher specificity targeted degradation, and the localized secretion of degraders from engineered cells. The tunability and modularity of our genetically encodable EndoTags should contribute to deciphering the relationship between receptor engagement and cellular trafficking, and they have considerable therapeutic potential as targeted degradation inducers, signaling activators for endocytosis-dependent pathways, and cellular uptake inducers for targeted antibody drug and RNA conjugates.
]]></description>
<dc:creator>Huang, B.</dc:creator>
<dc:creator>Abedi, M.</dc:creator>
<dc:creator>Ahn, G.</dc:creator>
<dc:creator>Coventry, B.</dc:creator>
<dc:creator>Sappington, I.</dc:creator>
<dc:creator>Wang, R.</dc:creator>
<dc:creator>Schlichthaerle, T.</dc:creator>
<dc:creator>Zhang, J. Z.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Goreshnik, I.</dc:creator>
<dc:creator>Chiu, C. W.</dc:creator>
<dc:creator>Chazin-Gray, A.</dc:creator>
<dc:creator>Chan, S.</dc:creator>
<dc:creator>Gerben, S.</dc:creator>
<dc:creator>Murray, A.</dc:creator>
<dc:creator>Wang, S.</dc:creator>
<dc:creator>O'Neill, J.</dc:creator>
<dc:creator>Yeh, R.</dc:creator>
<dc:creator>Misquith, A.</dc:creator>
<dc:creator>Wolf, A.</dc:creator>
<dc:creator>Tomasovic, L. M.</dc:creator>
<dc:creator>Piraner, D. I.</dc:creator>
<dc:creator>Gonzalez, M. J. D.</dc:creator>
<dc:creator>Bennett, N. R.</dc:creator>
<dc:creator>Venkatesh, P.</dc:creator>
<dc:creator>Ahlrichs, M.</dc:creator>
<dc:creator>Dobbins, C.</dc:creator>
<dc:creator>Yang, W.</dc:creator>
<dc:creator>Wang, X.</dc:creator>
<dc:creator>Vafeados, D.</dc:creator>
<dc:creator>Mout, R.</dc:creator>
<dc:creator>Shivaei, S.</dc:creator>
<dc:creator>Cao, L.</dc:creator>
<dc:creator>Carter, L.</dc:creator>
<dc:creator>Stewart, L.</dc:creator>
<dc:creator>Spangler, J. B.</dc:creator>
<dc:creator>Bernardes, G. J. L.</dc:creator>
<dc:creator>Roybal, K. T.</dc:creator>
<dc:creator>Greisen, P. J.</dc:creator>
<dc:creator>Li, X.</dc:creator>
<dc:creator>Bertozzi, C.</dc:creator>
<dc:creator>Baker, D.</dc:creator>
<dc:date>2023-08-21</dc:date>
<dc:identifier>doi:10.1101/2023.08.19.553321</dc:identifier>
<dc:title><![CDATA[Designed Endocytosis-Triggering Proteins mediate Targeted Degradation and amplify signaling]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.24.554677v1?rss=1">
<title>
<![CDATA[
Diversity in Notch ligand-receptor signaling interactions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.24.554677v1?rss=1</link>
<description><![CDATA[
The Notch signaling pathway uses families of ligands and receptors to transmit signals to nearby cells. These components are expressed in diverse combinations in different cell types, interact in a many-to-many fashion, both within the same cell (in cis) and between cells (in trans), and their interactions are modulated by Fringe glycosyltransferases. A fundamental question is how the strength of Notch signaling depends on which pathway components are expressed, at what levels, and in which cells. Here, we used a quantitative, bottom-up, cell-based approach to systematically characterize trans-activation, cis-inhibition, and cis-activation signaling efficiencies across a range of ligand and Fringe expression levels in two mammalian cell types. Each ligand (Dll1, Dll4, Jag1, and Jag2) and receptor variant (Notch1 and Notch2) analyzed here exhibited a unique profile of interactions, Fringe-dependence, and signaling outcomes. All four ligands were able to bind receptors in cis and in trans, and all ligands trans-activated both receptors, although Jag1-Notch1 signaling was substantially weaker than other ligand-receptor combinations. Cis-interactions were predominantly inhibitory, with the exception of the Dll1-and Dll4-Notch2 pairs, which exhibited cis-activation stronger than trans-activation. Lfng strengthened Delta-mediated trans-activation and weakened Jagged-mediated trans-activation for both receptors. Finally, cis-ligands showed diverse cis-inhibition strengths, which depended on the identity of the trans-ligand as well as the receptor. The map of receptor-ligand-Fringe interaction outcomes revealed here should help guide rational perturbation and control of the Notch pathway.
]]></description>
<dc:creator>Kuintzle, R.</dc:creator>
<dc:creator>Santat, L. A.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:date>2023-08-25</dc:date>
<dc:identifier>doi:10.1101/2023.08.24.554677</dc:identifier>
<dc:title><![CDATA[Diversity in Notch ligand-receptor signaling interactions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.25.554381v1?rss=1">
<title>
<![CDATA[
Using a multiscale lidar approach to determine variation in canopy structure from African forest elephant trails. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.25.554381v1?rss=1</link>
<description><![CDATA[
Recently classified as a unique species by the IUCN, African forest elephants (Loxodonta cyclotis) are critically endangered due to severe poaching. With limited knowledge about their ecological role due to the dense tropical forests they inhabit in central Africa, it is unclear how the Afrotropics would change if forest elephants were to go extinct. Although their role as seed dispersers is well known, they may also drive large-scale processes that determine forest structure, through the creation of elephant trails and browsing the understory and allowing larger, carbon-dense trees to succeed. Multiple scales of lidar were collected by NASA in Lope National Park, Gabon from 2015-2022. Utilizing two airborne lidar datasets and one spaceborne lidar in an African forest elephant stronghold, detailed canopy structural information was used in conjunction with elephant trail data to determine how forest structure varies on and off trails. Forest above elephant trails displayed different structural characteristics than forested areas off trails, with lower canopy height, canopy cover, and different vertical distribution of plant mass. Less plant area density was found on trails at 1 m in height, while more vegetation was found at 12 m, compared to off trail locations. Trails with previous logging history had lower plant area in the top of the canopy.
]]></description>
<dc:creator>Keany, J. M.</dc:creator>
<dc:creator>Burns, P.</dc:creator>
<dc:creator>Abraham, A.</dc:creator>
<dc:creator>Jantz, P.</dc:creator>
<dc:creator>Makaga, L.</dc:creator>
<dc:creator>Saatchi, S.</dc:creator>
<dc:creator>Maisels, F.</dc:creator>
<dc:creator>Abernethy, K.</dc:creator>
<dc:creator>Doughty, C.</dc:creator>
<dc:date>2023-08-27</dc:date>
<dc:identifier>doi:10.1101/2023.08.25.554381</dc:identifier>
<dc:title><![CDATA[Using a multiscale lidar approach to determine variation in canopy structure from African forest elephant trails.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.08.30.555626v1?rss=1">
<title>
<![CDATA[
HCR spectral imaging: 10-plex, quantitative, high-resolution RNA and protein imaging in highly autofluorescent samples 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.08.30.555626v1?rss=1</link>
<description><![CDATA[
Signal amplification based on the mechanism of hybridization chain reaction (HCR) provides a unified framework for multiplex, quantitative, high-resolution imaging of RNA and protein targets in highly autofluorescent samples. With conventional bandpass imaging, multiplexing is typically limited to four or five targets due to the difficulty in separating signals generated by fluorophores with overlapping spectra. Spectral imaging has offered the conceptual promise of higher levels of multiplexing, but it has been challenging to realize this potential in highly autofluorescent samples including whole-mount vertebrate embryos. Here, we demonstrate robust HCR spectral imaging with linear unmixing, enabling simultaneous imaging of 10 RNA and/or protein targets in whole-mount zebrafish embryos and mouse brain sections. Further, we demonstrate that the amplified and unmixed signal in each of 10 channels is quantitative, enabling accurate and precise relative quantitation of RNA and/or protein targets with subcellular resolution, and RNA absolute quantitation with single-molecule resolution, in the anatomical context of highly autofluorescent samples.

SUMMARYSpectral imaging with signal amplification based on the mechanism of hybridization chain reaction enables robust 10-plex, quantitative, high-resolution imaging of RNA and protein targets in whole-mount vertebrate embryos and brain sections.
]]></description>
<dc:creator>Schulte, S. J.</dc:creator>
<dc:creator>Fornace, M. E.</dc:creator>
<dc:creator>Hall, J. K.</dc:creator>
<dc:creator>Pierce, N. A.</dc:creator>
<dc:date>2023-08-30</dc:date>
<dc:identifier>doi:10.1101/2023.08.30.555626</dc:identifier>
<dc:title><![CDATA[HCR spectral imaging: 10-plex, quantitative, high-resolution RNA and protein imaging in highly autofluorescent samples]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.01.555371v1?rss=1">
<title>
<![CDATA[
Metabolic evolution of pyranopterin-dependent biochemistry 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.01.555371v1?rss=1</link>
<description><![CDATA[
Molybdenum (Mo)-dependent biochemistry is essential for many key metabolic pathways. However, theory and geological evidence suggests that its solubility during long intervals with low dioxygen would have limited its availability on early Earth. We developed models of metabolic evolution and found that reactions employing tungsten (W)-dependent biochemistry likely preceded Mo-dependent reactions, where Mo-usage increased dramatically after the production of dioxygen. Consistent with this finding, we analyzed genomes from over 65,000 phylogenetically diverse microbes and metagenomes from an environmental dataset, and we observed that dioxygen-utilizing prokaryotes living in aerobic niches are enriched with Mo-dependent enzymes as compared to anaerobic microbes. As an independent evaluation of this hypothesis, we combined protein language models, machine learning, and phylogenomic analysis to build a classifier for W- or Mo-pterin dependence in the DMSO reductase superfamily, and we found that W-pterin-dependent enzymes cluster near the root of the tree and that a subset of late-evolving aldehyde oxidoreductases (AORs) from aerobes are predicted to rely on Mo instead of W. Overall, our combination of metabolic modeling, phenotypic analysis, machine learning, and phylogenomic analysis suggest that Mo-pterin-dependent biochemistry likely derived from W-pterin-dependent biochemistry, and that Mo-usage increased drastically after the rise of oxygen.
]]></description>
<dc:creator>Goldford, J. E.</dc:creator>
<dc:creator>Murali, R.</dc:creator>
<dc:creator>Valentine, J. S.</dc:creator>
<dc:creator>Fischer, W. W.</dc:creator>
<dc:date>2023-09-05</dc:date>
<dc:identifier>doi:10.1101/2023.09.01.555371</dc:identifier>
<dc:title><![CDATA[Metabolic evolution of pyranopterin-dependent biochemistry]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.03.556122v1?rss=1">
<title>
<![CDATA[
Accurate single-molecule spot detection for image-based spatial transcriptomics with weakly supervised deep learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.03.556122v1?rss=1</link>
<description><![CDATA[
Image-based spatial transcriptomics methods enable transcriptome-scale gene expression measurements with spatial information but require complex, manually-tuned analysis pipelines. We present Polaris, an analysis pipeline for image-based spatial transcriptomics that combines deep learning models for cell segmentation and spot detection with a probabilistic gene decoder to quantify single-cell gene expression accurately. Polaris offers a unifying, turnkey solution for analyzing spatial transcriptomics data from MERFSIH, seqFISH, or ISS experiments. Polaris is available through the DeepCell software library (https://github.com/vanvalenlab/deepcell-spots) and https://www.deepcell.org.
]]></description>
<dc:creator>Laubscher, E.</dc:creator>
<dc:creator>Wang, X.</dc:creator>
<dc:creator>Razin, N.</dc:creator>
<dc:creator>Dougherty, T.</dc:creator>
<dc:creator>Xu, R.</dc:creator>
<dc:creator>Ombelets, L.</dc:creator>
<dc:creator>Pao, E.</dc:creator>
<dc:creator>Moffitt, J.</dc:creator>
<dc:creator>Yue, Y.</dc:creator>
<dc:creator>Van Valen, D. A.</dc:creator>
<dc:date>2023-09-05</dc:date>
<dc:identifier>doi:10.1101/2023.09.03.556122</dc:identifier>
<dc:title><![CDATA[Accurate single-molecule spot detection for image-based spatial transcriptomics with weakly supervised deep learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.04.556218v1?rss=1">
<title>
<![CDATA[
HIF1A contributes to the survival of aneuploid and mosaic pre-implantation embryos 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.04.556218v1?rss=1</link>
<description><![CDATA[
Human fertility is suboptimal in part by error-prone divisions during early cleavage stages, which frequently result in chromosomal aneuploidy. Most human pre-implantation embryos are mosaics of euploid and aneuploid cells, yet those with a low proportion of aneuploid cells can develop to term at rates similar to fully euploid embryos. How embryos manage aneuploidy during early development remains poorly understood - yet this knowledge is crucial for improving fertility outcomes and reducing developmental defects. To investigate these mechanisms, we established a new mouse model of chromosome mosaicism to trace the fate of aneuploid cells during pre-implantation development. We previously used the Mps1 inhibitor reversine to induce aneuploidy. Here, we demonstrate that the more specific Mps1 inhibitor AZ3146 similarly disrupts chromosome segregation but supports higher developmental potential than reversine. AZ3146-treated embryos transiently upregulate Hypoxia Inducible-Factor-1A (HIF1A) without triggering p53 activation. Given that pre-implantation embryos develop in a hypoxic environment in vivo, we further explored the role of oxygen tension. Hypoxia exposure in vitro reduced DNA damage in response to Mps1 inhibition and increased the proportion of euploid cells in mosaic epiblast. Conversely, HIF1A inhibition decreased the proportion of aneuploid cells. Together, these findings uncover a role for hypoxia signaling in modulating the response to chromosomal errors and suggest new strategies to improve the developmental potential of mosaic human embryos.
]]></description>
<dc:creator>Sanchez-Vasquez, E.</dc:creator>
<dc:creator>Zernicka-Goetz, M.</dc:creator>
<dc:creator>Bronner, M.</dc:creator>
<dc:date>2023-09-05</dc:date>
<dc:identifier>doi:10.1101/2023.09.04.556218</dc:identifier>
<dc:title><![CDATA[HIF1A contributes to the survival of aneuploid and mosaic pre-implantation embryos]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.06.555791v1?rss=1">
<title>
<![CDATA[
Descending control and regulation of spontaneous flight turns in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.06.555791v1?rss=1</link>
<description><![CDATA[
The clumped distribution of resources in the world has influenced the pattern of foraging behavior since the origins of life, selecting for a common locomotor search motif in which straight movements through resource-poor regions alternate with zig-zag exploration in resource-rich domains (Berg, 2000). For example, flies execute rapid changes in flight heading called body saccades during local search (Censi et al., 2013; Collett and Land, 1975; Schilstra and van Hateren, 1999; Wagner and Land, 1986), but suppress these turns during long-distance dispersal (Giraldo et al., 2018; Leitch et al., 2021) or when surging upwind after encountering an attractive odor plume (Budick and Dickinson, 2006; van Breugel and Dickinson, 2014). Here, we describe the key cellular components of a neural network in flies that generates spontaneous turns as well as a specialized neuron that inhibits the network to promote straight flight. Using 2-photon imaging, optogenetic activation, and genetic ablation, we show that only four descending neurons appear sufficient to generate the descending commands to execute flight saccades. The network is organized into two functional couplets--one for right turns and one for left--with each couplet consisting of an excitatory (DNae014) and inhibitory (DNb01) neuron that project to the flight motor neuropil within the ventral nerve cord. Using resources from recently published connectomes of the fly brain (Scheffer et al., 2020; Dorkenwald et al., 2023; Schlegel et al., 2023), we identified a large, unique interneuron (VES041) that forms inhibitory connections to all four saccade command neurons and created specific genetic driver lines for this cell. As predicted by its connectivity, activation of VES041 strongly suppresses saccades, suggesting that it regulates the transition between local search and long-distance dispersal. These results thus identify the critical elements of a network that not only structures the locomotor behavior of flies, but may also play a crucial role in their foraging ecology.
]]></description>
<dc:creator>Ros, I. G.</dc:creator>
<dc:creator>Omoto, J. J.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:date>2023-09-06</dc:date>
<dc:identifier>doi:10.1101/2023.09.06.555791</dc:identifier>
<dc:title><![CDATA[Descending control and regulation of spontaneous flight turns in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.13.557082v1?rss=1">
<title>
<![CDATA[
Conformational flexibility of HIV-1 envelope glycoproteins modulates transmitted / founder sensitivity to broadly neutralizing antibodies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.13.557082v1?rss=1</link>
<description><![CDATA[
HIV-1 envelope glycoproteins (Envs) mediate viral entry and are the sole target of neutralizing antibodies. Envs of most primary HIV-1 strains exist in a closed conformation and occasionally sample more open states. Thus, current knowledge guides immunogen design to mimic the closed Env conformation as the preferred target for eliciting broadly neutralizing antibodies (bnAbs) to block HIV-1 entry. Here we show that Env-preferred conformations of 6 out of 13 (46%) transmitted/founder (T/F) strains tested are incompletely closed. As a result, entry of these T/Fs into target cells is sensitive to antibodies that recognize internal epitopes exposed on open Env conformations. A cryo-electron microscopy structure of unliganded, incompletely closed T/F Envs (1059-SOSIP) at 3.6 [A] resolution exhibits an asymmetric configuration of Env protomers with increased sampling of states with incompletely closed trimer apex. Double electron-electron resonance spectroscopy provided further evidence for enriched occupancy of more open Env conformations. Consistent with conformational flexibility, 1059 Envs were associated with resistance to most bnAbs that exhibit reduced potency against functional Env intermediates. To follow the fate of incompletely closed Env in patients, we reconstructed de novo the post-transmission evolutionary pathway of a second T/F Env (CH040), which is sensitive to the V3-targeting antibody 19b and highly resistant to most bnAbs. Evolved viruses exhibited increased resistance to cold, soluble CD4 and 19b, all of which correlate with closing of the adapted Env trimer. Lastly, we show a correlation between efficient neutralization of multiple Env conformations and increased antiviral breadth of CD4-binding site (CD4bs) bnAbs. In particular, N6 bnAb, which uniquely recognizes different Env conformations, efficiently neutralizes 50% of the HIV-1 strains that were resistant to VRC01 and transmitted during the first-in-humans antibody-mediated prevention trial (HVTN 704). VRC01-resistant Envs are incompletely closed based on their sensitivity to cold and on partial sensitivity to antibodies targeting internal, typically occluded, epitopes. Most VRC01-resistant Envs retain the VRC01 epitope according to VRC01 binding to their gp120 subunit at concentrations that have no significant effect on virus entry, and they exhibit cross resistance to other CD4bs bnAbs that poorly recognize functional Env intermediates. Our findings refine current knowledge of Env conformational states and provide guidance for developing new strategies for bnAb immunotherapy and Env-based immunogen design.
]]></description>
<dc:creator>Ratnapriya, S.</dc:creator>
<dc:creator>Pothula, K. R.</dc:creator>
<dc:creator>Dam, K.-M. A.</dc:creator>
<dc:creator>Parthasarathy, D.</dc:creator>
<dc:creator>Benet, H. C.</dc:creator>
<dc:creator>Parsons, R.</dc:creator>
<dc:creator>Huang, X.</dc:creator>
<dc:creator>Sammour, S.</dc:creator>
<dc:creator>Janowska, K.</dc:creator>
<dc:creator>Harris, M.</dc:creator>
<dc:creator>Ahmed, S.</dc:creator>
<dc:creator>Sacco, S.</dc:creator>
<dc:creator>Sodroski, J.</dc:creator>
<dc:creator>Bridges, M.</dc:creator>
<dc:creator>Hubbell, W.</dc:creator>
<dc:creator>Acharya, P.</dc:creator>
<dc:creator>Herschhorn, A.</dc:creator>
<dc:date>2023-09-13</dc:date>
<dc:identifier>doi:10.1101/2023.09.13.557082</dc:identifier>
<dc:title><![CDATA[Conformational flexibility of HIV-1 envelope glycoproteins modulates transmitted / founder sensitivity to broadly neutralizing antibodies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.13.557571v1?rss=1">
<title>
<![CDATA[
Resolving the nanoscale structure of β-sheet assemblies using single-molecule orientation-localization microscopy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.13.557571v1?rss=1</link>
<description><![CDATA[
Synthetic peptides that self-assemble into cross-{beta} fibrils have remarkable utility as engineered biomaterials due to their modularity and biocompatibility, but their structural and morphological similarity to amyloid species has been a long-standing concern for their translation. Further, their polymorphs are difficult to characterize using spectroscopic and imaging techniques that rely on ensemble averaging to achieve high resolution. Here, we utilize single-molecule orientation-localization microscopy (SMOLM) to characterize fibrils formed by the designed amphipathic enantiomers, KFE8L and KFE8D, and the pathological amyloid-beta peptide A{beta}42. SMOLM reveals that the orientations of Nile red, as it transiently binds to both KFE8 and A{beta}42, are consistent with a helical (bilayer) ribbon structure and convey the precise tilt of the fibrils inner and outer backbones. SMOLM also finds polymorphic branched and curved morphologies of KFE8 whose backbones exhibit much more heterogeneity than those of more typical straight fibrils. Thus, SMOLM is a powerful tool to interrogate the structural differences and polymorphism between engineered and pathological cross {beta}-rich fibrils.
]]></description>
<dc:creator>Zhou, W.</dc:creator>
<dc:creator>O'Neill, C. L.</dc:creator>
<dc:creator>Ding, T.</dc:creator>
<dc:creator>Zhang, O.</dc:creator>
<dc:creator>Rudra, J. S.</dc:creator>
<dc:creator>Lew, M. D.</dc:creator>
<dc:date>2023-09-14</dc:date>
<dc:identifier>doi:10.1101/2023.09.13.557571</dc:identifier>
<dc:title><![CDATA[Resolving the nanoscale structure of β-sheet assemblies using single-molecule orientation-localization microscopy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.14.543267v1?rss=1">
<title>
<![CDATA[
Universal preprocessing of single-cell genomics data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.14.543267v1?rss=1</link>
<description><![CDATA[
We describe a workflow for preprocessing a wide variety of single-cell genomics data types. The approach is based on parsing of machine-readable seqspec assay specifications to customize inputs for kb-python, which uses kallisto and bustools to catalog reads, error correct barcodes, and count reads. The universal preprocessing method is implemented in the Python package cellatlas that is available for download at: https://github.com/cellatlas/cellatlas/.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Sullivan, D. K.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2023-09-15</dc:date>
<dc:identifier>doi:10.1101/2023.09.14.543267</dc:identifier>
<dc:title><![CDATA[Universal preprocessing of single-cell genomics data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.15.557999v1?rss=1">
<title>
<![CDATA[
Comparison of image registration techniques in functional ultrasound imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.15.557999v1?rss=1</link>
<description><![CDATA[
Functional Ultrasound Imaging (fUSI) is an emerging hemodynamic-based functional neuroimaging technique that combines high spatiotemporal resolution and sensitivity, as well as extensive brain coverage, enabling a range of applications in both control and disease animal models. Based on power Doppler (pD) imaging, fUSI measures changes in cerebral blood volume (CBV) by detecting the back-scattered echoes from red blood cells moving within its field of view (FOV). However, the expansion of fUSI technology is partly limited by the challenge to co-register pD vascular maps acquired across different sessions or animals to one reference; an approach that could widen the scope of experimental paradigms and enable advanced data analysis tools. In this study, we seek to address this critical limitation. We evaluate six image registration techniques, predominantly used in other neuroimaging studies, using 2D sagittal whole-brain fUSI data from 82 anesthetized mice, and tested the quality of registration using multiple metrics. Our findings indicate a substantial enhancement in the alignment of fUSI images post registration. Among the tested techniques, the non-rigid registration algorithm Imregdeform yielded superior performance. We offer the first comparative study of image registration techniques for a 2D fUSI brain dataset, paving a way for improved utilization of fUSI in future pre-clinical research applications.
]]></description>
<dc:creator>Zhong, S.</dc:creator>
<dc:creator>Agyeman, K.</dc:creator>
<dc:creator>Syed, S.</dc:creator>
<dc:creator>Tobing, R. L.</dc:creator>
<dc:creator>Choi, W.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Lee, D. J.</dc:creator>
<dc:creator>Christopoulos, V.</dc:creator>
<dc:date>2023-09-16</dc:date>
<dc:identifier>doi:10.1101/2023.09.15.557999</dc:identifier>
<dc:title><![CDATA[Comparison of image registration techniques in functional ultrasound imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.17.558131v1?rss=1">
<title>
<![CDATA[
Biophysically Interpretable Inference of Cell Types from Multimodal Sequencing Data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.17.558131v1?rss=1</link>
<description><![CDATA[
Multimodal, single-cell genomics technologies enable simultaneous capture of multiple facets of DNA and RNA processing in the cell. This creates opportunities for transcriptome-wide, mechanistic studies of cellular processing in heterogeneous cell types, with applications ranging from inferring kinetic differences between cells, to the role of stochasticity in driving heterogeneity. However, current methods for determining cell types or  clusters present in multimodal data often rely on ad hoc or independent treatment of modalities, and assumptions ignoring inherent properties of the count data. To enable interpretable and consistent cell cluster determination from multimodal data, we present meK-Means (mechanistic K-Means) which integrates modalities and learns underlying, shared biophysical states through a unifying model of transcription. In particular, we demonstrate how meK-Means can be used to cluster cells from unspliced and spliced mRNA count modalities. By utilizing the causal, physical relationships underlying these modalities, we identify shared transcriptional kinetics across cells, which induce the observed gene expression profiles, and provide an alternative definition for  clusters through the governing parameters of cellular processes.
]]></description>
<dc:creator>Chari, T.</dc:creator>
<dc:creator>Gorin, G.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2023-09-17</dc:date>
<dc:identifier>doi:10.1101/2023.09.17.558131</dc:identifier>
<dc:title><![CDATA[Biophysically Interpretable Inference of Cell Types from Multimodal Sequencing Data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.18.558369v1?rss=1">
<title>
<![CDATA[
Automated construction of cognitive maps with predictive coding 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.18.558369v1?rss=1</link>
<description><![CDATA[
Humans construct internal cognitive maps of their environment directly from sensory inputs without access to a system of explicit coordinates or distance measurements. While machine learning algorithms like SLAM utilize specialized inference procedures to identify visual features and construct spatial maps from visual and odometry data, the general nature of cognitive maps in the brain suggests a unified mapping algorithmic strategy that can generalize to auditory, tactile, and linguistic inputs. Here, we demonstrate that predictive coding provides a natural and versatile neural network algorithm for constructing spatial maps using sensory data. We introduce a framework in which an agent navigates a virtual environment while engaging in visual predictive coding using a self-attention-equipped convolutional neural network. While learning a next image prediction task, the agent automatically constructs an internal representation of the environment that quantitatively reflects spatial distances. The internal map enables the agent to pinpoint its location relative to landmarks using only visual information.The predictive coding network generates a vectorized encoding of the environment that supports vector navigation where individual latent space units delineate localized, overlapping neighborhoods in the environment. Broadly, our work introduces predictive coding as a unified algorithmic framework for constructing cognitive maps that can naturally extend to the mapping of auditory, sensorimotor, and linguistic inputs.
]]></description>
<dc:creator>Gornet, J. A.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2023-09-19</dc:date>
<dc:identifier>doi:10.1101/2023.09.18.558369</dc:identifier>
<dc:title><![CDATA[Automated construction of cognitive maps with predictive coding]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.19.558526v1?rss=1">
<title>
<![CDATA[
Serotonin predictively encodes value 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.19.558526v1?rss=1</link>
<description><![CDATA[
The in vivo responses of dorsal raphe nucleus (DRN) serotonin neurons to emotionally-salient stimuli are a puzzle. Existing theories centred on reward, surprise, or uncertainty individually account for some aspects of serotonergic activity but not others. Here we find a unifying perspective in a biologically-constrained predictive code for cumulative future reward, a quantity called state value in reinforcement learning. Through simulations of trace conditioning experiments common in the serotonin literature, we show that our theory, called value prediction, intuitively explains phasic activation by both rewards and punishments, preference for surprising rewards but absence of a corresponding preference for punishments, and contextual modulation of tonic firing--observations that currently form the basis of many and varied serotonergic theories. Next, we re-analyzed data from a recent experiment and found serotonin neurons with activity patterns that are a surprisingly close match: our theory predicts the marginal effect of reward history on population activity with a precision <<0.1 Hz neuron-1. Finally, we directly compared against quantitative formulations of existing ideas and found that our theory best explains both within-trial activity dynamics and trial-to-trial modulations, offering performance usually several times better than the closest alternative. Overall, our results show that previous models are not wrong, but incomplete, and that reward, surprise, salience, and uncertainty are simply different faces of a predictively-encoded value signal. By unifying previous theories, our work represents an important step towards understanding the potentially heterogeneous computational roles of serotonin in learning, behaviour, and beyond.
]]></description>
<dc:creator>Harkin, E. F.</dc:creator>
<dc:creator>Grossman, C. D.</dc:creator>
<dc:creator>Cohen, J. Y.</dc:creator>
<dc:creator>Beïque, J.-C.</dc:creator>
<dc:creator>Naud, R.</dc:creator>
<dc:date>2023-09-21</dc:date>
<dc:identifier>doi:10.1101/2023.09.19.558526</dc:identifier>
<dc:title><![CDATA[Serotonin predictively encodes value]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.19.558483v1?rss=1">
<title>
<![CDATA[
AgRP neuron activity promotes associations between sensory and nutritive signals to guide flavor preference 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.19.558483v1?rss=1</link>
<description><![CDATA[
ObjectiveThe learned associations between sensory cues (e.g., taste, smell) and nutritive value (e.g., calories, post-ingestive signaling) of foods powerfully influences our eating behavior [1], but the neural circuits that mediate these associations are not well understood. Here, we examined the role of agouti-related protein (AgRP)-expressing neurons - neurons which are critical drivers of feeding behavior [2; 3] - in mediating flavor-nutrient learning (FNL).

MethodsBecause mice prefer flavors associated with AgRP neuron activity suppression [4], we examined how optogenetic stimulation of AgRP neurons during intake influences FNL, and used fiber photometry to determine how endogenous AgRP neuron activity tracks associations between flavors and nutrients.

ResultsWe unexpectedly found that tonic activity in AgRP neurons during FNL potentiated, rather than prevented, the development of flavor preferences. There were notable sex differences in the mechanisms for this potentiation. Specifically, in male mice, AgRP neuron activity increased flavor consumption during FNL training, thereby strengthening the association between flavors and nutrients. In female mice, AgRP neuron activity enhanced flavor-nutrient preferences independently of consumption during training, suggesting that AgRP neuron activity enhances the reward value of the nutrient-paired flavor. Finally, in vivo neural activity analyses demonstrated that acute AgRP neuron dynamics track the association between flavors and nutrients in both sexes.

ConclusionsOverall, these data (1) demonstrate that AgRP neuron activity enhances associations between flavors and nutrients in a sex-dependent manner and (2) reveal that AgRP neurons track and update these associations on fast timescales. Taken together, our findings provide new insight into the role of AgRP neurons in assimilating sensory and nutritive signals for food reinforcement.
]]></description>
<dc:creator>Nyema, N. T.</dc:creator>
<dc:creator>McKnight, A. D.</dc:creator>
<dc:creator>Vargas-Elvira, A. G.</dc:creator>
<dc:creator>Schneps, H. M.</dc:creator>
<dc:creator>Gold, E. G.</dc:creator>
<dc:creator>Myers, K. P.</dc:creator>
<dc:creator>Alhadeff, A. L.</dc:creator>
<dc:date>2023-09-22</dc:date>
<dc:identifier>doi:10.1101/2023.09.19.558483</dc:identifier>
<dc:title><![CDATA[AgRP neuron activity promotes associations between sensory and nutritive signals to guide flavor preference]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.20.558642v1?rss=1">
<title>
<![CDATA[
Redox Active Plant Phenolic, Acetosyringone, for Electrogenetic Signaling 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.20.558642v1?rss=1</link>
<description><![CDATA[
Redox is a unique, programmable modality capable of bridging communication between biology and electronics. Previous studies have shown that the E. coli redox-responsive OxyRS regulon can be re-wired to accept electrochemically generated hydrogen peroxide (H2O2) as an inducer of gene expression. Here we report that the redox-active phenolic plant signaling molecule acetosyringone (AS) can also induce gene expression from the OxyRS regulon. AS must be oxidized, however, as the reduced state present under normal conditions cannot induce gene expression. Thus, AS serves as a "pro-signaling molecule" that can be activated by its oxidation - in our case by application of oxidizing potential to an electrode. We show that the OxyRS regulon is not induced electrochemically if the imposed electrode potential is in the mid-physiological range. Electronically sliding the applied potential to either oxidative or reductive extremes induces this regulon but through different mechanisms: reduction of O2 to form H2O2 or oxidation of AS. Fundamentally, this work reinforces the emerging concept that redox signaling depends more on molecular activities than molecular structure. From an applications perspective, the creation of an electronically programmed "pro-signal" dramatically expands the toolbox for electronic control of biological responses in microbes, including in complex environments, cell-based materials, and biomanufacturing.
]]></description>
<dc:creator>Zakaria, F. R.</dc:creator>
<dc:creator>Chen, C.-Y.</dc:creator>
<dc:creator>Li, J.</dc:creator>
<dc:creator>Wang, S. P.</dc:creator>
<dc:creator>Payne, G. F.</dc:creator>
<dc:creator>Bentley, W. E.</dc:creator>
<dc:date>2023-09-22</dc:date>
<dc:identifier>doi:10.1101/2023.09.20.558642</dc:identifier>
<dc:title><![CDATA[Redox Active Plant Phenolic, Acetosyringone, for Electrogenetic Signaling]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.23.559120v1?rss=1">
<title>
<![CDATA[
Engineering antigen-specific tolerance to an artificial protein hydrogel 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.23.559120v1?rss=1</link>
<description><![CDATA[
Artificial protein hydrogels are an emerging class of biomaterials with numerous prospective applications in tissue engineering and regenerative medicine. These materials are likely to be immunogenic due their frequent incorporation of novel amino acid sequence domains, which often serve a functional role within the material itself. We engineered injectable "self" and "non-self" artificial protein hydrogels which were predicted to have divergent immune outcomes in vivo on the basis of their primary amino acid sequence. Following implantation in mouse, the non-self gels raised significantly higher anti-gel antibody titers than the corresponding self gels. Prophylactic administration of a fusion antibody targeting the non-self hydrogel epitopes to DEC-205, an endocytic receptor involved in Treg induction, fully suppressed the elevated antibody titer against the non-self gels. These results suggest that the clinical immune response to artificial protein biomaterials, including those that contain highly antigenic sequence domains, can be tuned through the induction of antigen-specific tolerance.
]]></description>
<dc:creator>Rapp, P. B.</dc:creator>
<dc:creator>Baccile, J. A.</dc:creator>
<dc:creator>Galimidi, R. P.</dc:creator>
<dc:creator>Vielmetter, J.</dc:creator>
<dc:date>2023-09-23</dc:date>
<dc:identifier>doi:10.1101/2023.09.23.559120</dc:identifier>
<dc:title><![CDATA[Engineering antigen-specific tolerance to an artificial protein hydrogel]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.28.560045v1?rss=1">
<title>
<![CDATA[
HI-FISH: WHOLE BRAIN IN SITU MAPPING OF NEURONAL ACTIVATION IN DROSOPHILA DURING SOCIAL BEHAVIORS AND OPTOGENETIC STIMULATION 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.28.560045v1?rss=1</link>
<description><![CDATA[
Monitoring neuronal activity at single-cell resolution in freely moving Drosophila engaged in social behaviors is challenging because of their small size and lack of transparency. Extant methods, such as Flyception, are highly invasive. Whole-brain calcium imaging in head-fixed, walking flies is feasible but the animals cannot perform the consummatory phases of social behaviors like aggression or mating under these conditions. This has left open the fundamental question of whether neurons identified as functionally important for such behaviors using loss- or gain-of-function screens are actually active during the natural performance of such behaviors, and if so during which phase(s). Here we perform brain-wide mapping of active cells expressing the Immediate Early Gene hr38 using a high-sensitivity/low background FISH amplification method called HCR-3.0. Using double-labeling for hr38 mRNA and for GFP, we describe the activity of several classes of aggression-promoting neurons during courtship and aggression, including P1a cells, an intensively studied population of male-specific interneurons. Using HI-FISH in combination with optogenetic activation of aggression-promoting neurons (opto-HI-FISH) we identify candidate downstream functional targets of these cells in a brain-wide, unbiased manner. Finally we compare the activity of P1a neurons during sequential performance of courtship and aggression, using intronic vs. exonic hr38 probes to differentiate newly synthesized nuclear transcripts from cytoplasmic transcripts synthesized at an earlier time. These data provide evidence suggesting that different subsets of P1a neurons may be active during courtship vs. aggression. HI-FISH and associated methods may help to fill an important lacuna in the armamentarium of tools for neural circuit analysis in Drosophila.
]]></description>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:creator>Chiu, H. V.</dc:creator>
<dc:creator>Watanabe, K.</dc:creator>
<dc:date>2023-09-29</dc:date>
<dc:identifier>doi:10.1101/2023.09.28.560045</dc:identifier>
<dc:title><![CDATA[HI-FISH: WHOLE BRAIN IN SITU MAPPING OF NEURONAL ACTIVATION IN DROSOPHILA DURING SOCIAL BEHAVIORS AND OPTOGENETIC STIMULATION]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.28.559980v1?rss=1">
<title>
<![CDATA[
Adaptation to space conditions of novel bacterial species isolated from the International Space Station revealed by functional gene annotations and comparative genome analysis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.28.559980v1?rss=1</link>
<description><![CDATA[
BackgroundThe extreme environment of the International Space Station (ISS) puts selective pressure on microorganisms unintentionally introduced during its 20+ years of service as a low-orbit science platform and human habitat. Such pressure leads to the development of new features not found in the Earth-bound relatives, which enable them to adapt to unfavorable conditions.

ResultsIn this study, we generated the functional annotation of the genomes of five newly identified species of Gram-positive bacteria, four of which are non-spore-forming and one spore-forming, all isolated from the ISS. Using a deep-learning based tool - deepFRI - we were able to functionally annotate close to 100% of protein-coding genes in all studied species, overcoming other annotation tools. Our comparative genomic analysis highlights common characteristics across all five species and specific genetic traits that appear unique to these ISS microorganisms. Proteome analysis mirrored these genomic patterns, revealing similar traits. The collective annotations suggest adaptations to life in space, including the management of hypoosmotic stress related to microgravity via mechanosensitive channel proteins, increased DNA repair activity to counteract heightened radiation exposure, and the presence of mobile genetic elements enhancing metabolism. In addition, our findings suggest the evolution of certain genetic traits indicative of potential pathogenic capabilities, such as small molecule and peptide synthesis and ATP-dependent transporters. These traits, exclusive to the ISS microorganisms, further substantiate previous reports explaining why microbes exposed to space conditions demonstrate enhanced antibiotic resistance and pathogenicity.

ConclusionOur findings indicate that the microorganisms isolated from ISS we studied have adapted to life in space. Evidence such as mechanosensitive channel proteins, increased DNA repair activity, as well as metallopeptidases and novel S-layer oxidoreductases suggest a convergent adaptation among these diverse microorganisms, potentially complementing one another within the context of the microbiome. The common genes that facilitate adaptation to the ISS environment may enable bioproduction of essential biomolecules need during future space missions, or serve as potential drug targets, if these microorganisms pose health risks.
]]></description>
<dc:creator>SZYDLOWSKI, L. M.</dc:creator>
<dc:creator>Bulbul, A.</dc:creator>
<dc:creator>Simpson, A. C.</dc:creator>
<dc:creator>Kaya, D. E.</dc:creator>
<dc:creator>Singh, N. K.</dc:creator>
<dc:creator>Sezerman, U. O.</dc:creator>
<dc:creator>Labaj, P. P.</dc:creator>
<dc:creator>Kosciolek, T.</dc:creator>
<dc:creator>Venkateswaran, K.</dc:creator>
<dc:date>2023-09-30</dc:date>
<dc:identifier>doi:10.1101/2023.09.28.559980</dc:identifier>
<dc:title><![CDATA[Adaptation to space conditions of novel bacterial species isolated from the International Space Station revealed by functional gene annotations and comparative genome analysis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-09-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.09.30.560339v1?rss=1">
<title>
<![CDATA[
Antagonists of the stress and opioid systems restore the functional connectivity of the prefrontal cortex during alcohol withdrawal through divergent mechanisms. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.09.30.560339v1?rss=1</link>
<description><![CDATA[
Chronic alcohol consumption leads to dependence and withdrawal symptoms upon cessation, contributing to persistent use. However, the brain network mechanisms by which the brain orchestrates alcohol withdrawal and how these networks are affected by pharmacological treatments remain elusive. Recent work revealed that alcohol withdrawal produces a widespread increase in coordinated brain activity and a decrease in modularity of the whole-brain functional network using single-cell whole-brain imaging of immediate early genes. This decreased modularity and functional hyperconnectivity are hypothesized to be novel biomarkers of alcohol withdrawal in alcohol dependence, which could potentially be used to evaluate the efficacy of new medications for alcohol use disorder. However, there is no evidence that current FDA-approved medications or experimental treatments known to reduce alcohol drinking in animal models can normalize the changes in whole-brain functional connectivity. In this report, we tested the effect of R121919, a CRF1 antagonist, and naltrexone, an FDA-approved treatment for alcohol use disorder, on whole-brain functional connectivity using the cellular marker FOS combined with graph theory and advanced network analyses. Results show that both R121919 and naltrexone restored the functional connectivity of the prefrontal cortex during alcohol withdrawal, but through divergent mechanisms. Specifically, R121919 increased FOS activation in the prefrontal cortex, partially restored modularity, and normalized connectivity, particularly in CRF1-rich regions, including the prefrontal, pallidum, and extended amygdala circuits. On the other hand, naltrexone decreased FOS activation throughout the brain, decreased modularity, and increased connectivity overall except for the Mu opioid receptor-rich regions, including the thalamus. These results identify the brain networks underlying the pharmacological effects of R121919 and naltrexone and demonstrate that these drugs restored different aspects of functional connectivity of the prefrontal cortex, pallidum, amygdala, and thalamus during alcohol withdrawal. Notably, these effects were particularly prominent in CRF1-and Mu opioid receptors-rich regions highlighting the potential of whole-brain functional connectivity using FOS as a tool for identifying neuronal network mechanisms underlying the pharmacological effects of existing and new medications for alcohol use disorder.
]]></description>
<dc:creator>Carrette, L. L. G.</dc:creator>
<dc:creator>Santos, A.</dc:creator>
<dc:creator>Brennan, M.</dc:creator>
<dc:creator>Othman, D.</dc:creator>
<dc:creator>Collazo, A.</dc:creator>
<dc:creator>George, O.</dc:creator>
<dc:date>2023-10-02</dc:date>
<dc:identifier>doi:10.1101/2023.09.30.560339</dc:identifier>
<dc:title><![CDATA[Antagonists of the stress and opioid systems restore the functional connectivity of the prefrontal cortex during alcohol withdrawal through divergent mechanisms.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.03.560249v1?rss=1">
<title>
<![CDATA[
Method for Spatially Confined Stimulation by Retinal Scanning Displays: Are Blind Spots Really Blind? 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.03.560249v1?rss=1</link>
<description><![CDATA[
Conventional displays, such as CRTs and LCDs, are commonly used to present and manipulate visual stimuli in many vision science studies. However, such displays pose difficulties when the goal is to constrain stimulation to specific retinal locations, so as to isolate their contribution to downstream effects. Scattered and refracted light can stimulate unintended areas, contaminating the outcomes. In this investigation, we evaluate a laser-based retinal scanning display for its ability to map and exclusively stimulate the retinal blind spot. This application stimulates melanopsin receptors inside the blind spot, separately from rod and cone photoreceptors, which lie outside the blind spot. This paper covers three experiments: 1. The initial exploratory observations; 2. the examination of pupillary responses, and; 3. the inference of implicit visual perception arising from the blind spot. We aimed to simultaneously validate our technical methods, while increasing our understanding of the role of melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) in vision and implicit visual perception.
]]></description>
<dc:creator>Tavakoli, A.-V.</dc:creator>
<dc:creator>Omata, T.</dc:creator>
<dc:creator>Imamura, T.</dc:creator>
<dc:creator>Ogawa, R.</dc:creator>
<dc:creator>Iwasaki, M.</dc:creator>
<dc:creator>del Rio Salgado, J.</dc:creator>
<dc:creator>Rossi, I.</dc:creator>
<dc:creator>Hung, S.-M.</dc:creator>
<dc:creator>Wu, D.-A.</dc:creator>
<dc:creator>Shimojo, S.</dc:creator>
<dc:date>2023-10-05</dc:date>
<dc:identifier>doi:10.1101/2023.10.03.560249</dc:identifier>
<dc:title><![CDATA[Method for Spatially Confined Stimulation by Retinal Scanning Displays: Are Blind Spots Really Blind?]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.06.561174v1?rss=1">
<title>
<![CDATA[
Co-transcriptional production of programmable RNA condensates and synthetic organelles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.06.561174v1?rss=1</link>
<description><![CDATA[
Condensation of RNA and proteins is central to cellular functions, and the ability to program it would be valuable in synthetic biology and synthetic cell science. Here we introduce a modular platform for engineering synthetic RNA condensates from tailor-made, branched RNA nanostructures that fold and assemble co-transcriptionally. Up to three orthogonal condensates can form simultaneously and selectively accumulate guest molecules. The RNA condensates can be expressed within synthetic cells to produce membrane-less organelles with controlled number, size, morphology and composition, and that display the ability to selectively capture proteins. The in situ expression of programmable RNA condensates could underpin spatial organisation of functionalities in both biological and synthetic cells.
]]></description>
<dc:creator>Fabrini, G.</dc:creator>
<dc:creator>Nuccio, S. P.</dc:creator>
<dc:creator>Stewart, J. M.</dc:creator>
<dc:creator>Lin, S.</dc:creator>
<dc:creator>Tang, A.</dc:creator>
<dc:creator>Rothemund, P. W. K.</dc:creator>
<dc:creator>Franco, E.</dc:creator>
<dc:creator>Di Antonio, M.</dc:creator>
<dc:creator>Di Michele, L.</dc:creator>
<dc:date>2023-10-06</dc:date>
<dc:identifier>doi:10.1101/2023.10.06.561174</dc:identifier>
<dc:title><![CDATA[Co-transcriptional production of programmable RNA condensates and synthetic organelles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.11.561775v1?rss=1">
<title>
<![CDATA[
Histone H3 E50K mutation confers oncogenic activity and supports an EMT phenotype 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.11.561775v1?rss=1</link>
<description><![CDATA[
Sequencing of human patient tumors has identified recurrent missense mutations in genes encoding core histones. We report that mutations that convert histone H3 amino acid 50 from a glutamate to a lysine (H3E50K) support an oncogenic phenotype in human cells. Expression of H3E50K is sufficient to transform human cells as evidenced by a dramatic increase in cell migration and invasion, and a statistically significant increase in proliferation and clonogenicity. H3E50K also increases the invasive phenotype in the context of co-occurring BRAF mutations, which are present in patient tumors characterized by H3E50K. H3E50 lies on the globular domain surface in a region that contacts H4 within the nucleosome. We find that H3E50K perturbs proximal H3 post-translational modifications globally and dysregulates gene expression, activating the epithelial to mesenchymal transition. Functional studies using S. cerevisiae reveal that, while yeast cells that express H3E50K as the sole copy of histone H3 show sensitivity to cellular stressors, including caffeine, H3E50K cells display some genetic interactions that are distinct from the characterized H3K36M oncohistone yeast model. Taken together, these data suggest that additional histone H3 mutations have the potential to be oncogenic drivers and function through distinct mechanisms that dysregulate gene expression.

SummaryO_LIRecurrent missense mutation that alter histone H3E50 were identified in patient tumors
C_LIO_LIH3E50K expression dysregulates global H3 post-translational modification, gene expression and may govern a transcriptional program associated with metastatic phenotypes
C_LIO_LIhht2-E50K yeast cells exhibit growth defects in the presence of DNA damaging agents
C_LI
]]></description>
<dc:creator>Sad, K.</dc:creator>
<dc:creator>Jones, C. Y.</dc:creator>
<dc:creator>Lustenberger, S.</dc:creator>
<dc:creator>Lee, R. S.</dc:creator>
<dc:creator>Elayavalli, S. R.</dc:creator>
<dc:creator>Farhi, J.</dc:creator>
<dc:creator>Lemon, L. D.</dc:creator>
<dc:creator>Fasken, M. B.</dc:creator>
<dc:creator>Corbett, A. H.</dc:creator>
<dc:creator>Spangle, J. M.</dc:creator>
<dc:date>2023-10-12</dc:date>
<dc:identifier>doi:10.1101/2023.10.11.561775</dc:identifier>
<dc:title><![CDATA[Histone H3 E50K mutation confers oncogenic activity and supports an EMT phenotype]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.13.562248v1?rss=1">
<title>
<![CDATA[
Widespread detoxifying NO reductases impart a distinct isotopic fingerprint on N2O under anoxia 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.13.562248v1?rss=1</link>
<description><![CDATA[
Nitrous oxide (N2O), a potent greenhouse gas, can be generated by compositionally complex microbial populations in diverse contexts. Accurately tracking the dominant biological sources of N2O has the potential to improve our understanding of N2O fluxes from soils as well as inform the diagnosis of human infections. Isotopic "Site Preference" (SP) values have been used towards this end, as bacterial and fungal nitric oxide reductases produce N2O with different isotopic fingerprints. Here we show that flavohemoglobin, a hitherto biogeochemically neglected yet widely distributed detoxifying bacterial NO reductase, imparts a distinct SP value onto N2O under anoxic conditions that correlates with typical environmental N2O SP measurements. We suggest a new framework to guide the attribution of N2O biological sources in nature and disease.

One-Sentence SummaryDetoxifying nitric oxide reductases impart a distinct isotopic biosignature on nitrous oxide.
]]></description>
<dc:creator>Wang, R.</dc:creator>
<dc:creator>Lonergan, Z.</dc:creator>
<dc:creator>Wilbert, S.</dc:creator>
<dc:creator>Eiler, J.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2023-10-14</dc:date>
<dc:identifier>doi:10.1101/2023.10.13.562248</dc:identifier>
<dc:title><![CDATA[Widespread detoxifying NO reductases impart a distinct isotopic fingerprint on N2O under anoxia]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.13.562302v1?rss=1">
<title>
<![CDATA[
The fatty liver disease-causing protein PNPLA3-I148M alters lipid droplet-Golgi dynamics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.13.562302v1?rss=1</link>
<description><![CDATA[
Non-alcoholic fatty liver disease (NAFLD), recently renamed metabolic dysfunction-associated steatotic liver disease (MASLD), is a progressive metabolic disorder that begins with aberrant triglyceride accumulation in the liver and can lead to cirrhosis and cancer. A common variant in the gene PNPLA3, encoding the protein PNPLA3-I148M, is the strongest known genetic risk factor for MASLD to date. Despite its discovery twenty years ago, the function of PNPLA3, and now the role of PNPLA3-I148M, remain unclear. In this study, we sought to dissect the biogenesis of PNPLA3 and PNPLA3-I148M and characterize changes induced by endogenous expression of the disease-causing variant. Contrary to bioinformatic predictions and prior studies with overexpressed proteins, we demonstrate here that PNPLA3 and PNPLA3-I148M are not endoplasmic reticulum-resident transmembrane proteins. To identify their intracellular associations, we generated a paired set of isogenic human hepatoma cells expressing PNPLA3 and PNPLA3-I148M at endogenous levels. Both proteins were enriched in lipid droplet, Golgi, and endosomal fractions. Purified PNPLA3 and PNPLA3-I148M proteins associated with phosphoinositides commonly found in these compartments. Despite a similar fractionation pattern as the wild-type variant, PNPLA3-I148M induced morphological changes in the Golgi apparatus, including increased lipid droplet-Golgi contact sites, which were also observed in I148M-expressing primary human patient hepatocytes. In addition to lipid droplet accumulation, PNPLA3-I148M expression caused significant proteomic and transcriptomic changes that resembled all stages of liver disease. Cumulatively, we validate an endogenous human cellular system for investigating PNPLA3-I148M biology and identify the Golgi apparatus as a central hub of PNPLA3-I148M-driven cellular change.

Significance StatementFatty liver disease affects nearly a quarter of the worlds population and has both environmental and genetic risk factors. A mutation in the gene PNPLA3 that converts Ile 148 to Met is the strongest known genetic risk factor for developing fatty liver disease. Using a series of techniques to track endogenous PNPLA3 and PNPLA3-I148M biogenesis and localization, we reveal new insights into how the mutation changes cellular dynamics. Although previous reports focus on its role on lipid droplets, we reveal that PNPLA3-I148M also functions at the Golgi apparatus, an organelle critical for protein transport into and out of the cell and lipid signaling. PNPLA3-I148M causes altered Golgi morphology and drives changes reminiscent of liver disease.
]]></description>
<dc:creator>Sherman, D. J.</dc:creator>
<dc:creator>Liu, L.</dc:creator>
<dc:creator>Mamrosh, J. L.</dc:creator>
<dc:creator>Xie, J.</dc:creator>
<dc:creator>Ferbas, J.</dc:creator>
<dc:creator>Lomenick, B.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Verma, R.</dc:creator>
<dc:creator>Rulifson, I. C.</dc:creator>
<dc:creator>Deshaies, R. J.</dc:creator>
<dc:date>2023-10-14</dc:date>
<dc:identifier>doi:10.1101/2023.10.13.562302</dc:identifier>
<dc:title><![CDATA[The fatty liver disease-causing protein PNPLA3-I148M alters lipid droplet-Golgi dynamics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.13.562303v1?rss=1">
<title>
<![CDATA[
Cleave and Rescue gamete killers create conditions for gene drive in plants 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.13.562303v1?rss=1</link>
<description><![CDATA[
Gene drive elements promote the spread of linked traits, even when their presence confers a fitness cost to carriers, and can be used to change the composition or fate of wild populations. Cleave and Rescue (ClvR) drive elements sit at a fixed chromosomal position and include a DNA sequence-modifying enzyme such as Cas9/gRNAs (the Cleaver/Toxin) that disrupts endogenous versions of an essential gene, and a recoded version of the essential gene resistant to cleavage (the Rescue/Antidote). ClvR spreads by creating conditions in which those lacking ClvR die because they lack functional versions of the essential gene. We demonstrate the essential features of ClvR gene drive in the plant Arabidopsis thaliana through killing of gametes that fail to inherit a ClvR that targets the essential gene YKT61, whose expression is required in male and female gametes for their survival. Resistant (uncleavable but functional) alleles, which can slow or prevent drive, were not observed. Modeling shows plant ClvRs are likely to be robust to certain failure modes and can be used to rapidly drive population modification or suppression. Possible applications in plant breeding, weed control, and conservation are discussed.
]]></description>
<dc:creator>Oberhofer, G.</dc:creator>
<dc:creator>Johnson, M.</dc:creator>
<dc:creator>Ivy, T.</dc:creator>
<dc:creator>Hay, B.</dc:creator>
<dc:date>2023-10-14</dc:date>
<dc:identifier>doi:10.1101/2023.10.13.562303</dc:identifier>
<dc:title><![CDATA[Cleave and Rescue gamete killers create conditions for gene drive in plants]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.12.562107v1?rss=1">
<title>
<![CDATA[
Generating counterfactual explanations of tumor spatial proteomes to discover effective strategies for enhancing immune infiltration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.12.562107v1?rss=1</link>
<description><![CDATA[
Cancer progression can be slowed down or halted via the activation of either endogenous or engineered T cells and their infiltration of the tumour microenvironment. Here we describe a deep-learning model that uses large-scale spatial proteomic profiles of tumours to generate minimal tumour perturbations that boost T-cell infiltration. The model integrates a counterfactual optimization strategy for the generation of the perturbations with the prediction of T-cell infiltration as a self-supervised machine-learning problem. We applied the model to 368 samples of metastatic melanoma and colorectal cancer assayed using 40-plex imaging mass cytometry, and discovered cohort-dependent combinatorial perturbations (CXCL9, CXCL10, CCL22 and CCL18 for melanoma, and CXCR4, PD-1, PD-L1 and CYR61 for colorectal cancer) that support T-cell infiltration across patient cohorts, as confirmed via in vitro experiments. Leveraging counterfactual-based predictions of spatial omics data may aid the design of cancer therapeutics.
]]></description>
<dc:creator>Wang, Z. J.</dc:creator>
<dc:creator>Xu, A. M.</dc:creator>
<dc:creator>Bhargava, A.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2023-10-16</dc:date>
<dc:identifier>doi:10.1101/2023.10.12.562107</dc:identifier>
<dc:title><![CDATA[Generating counterfactual explanations of tumor spatial proteomes to discover effective strategies for enhancing immune infiltration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.12.562112v1?rss=1">
<title>
<![CDATA[
The Interferon-inducible NAMPT acts as a protein phosphoribosylase to restrict viral infection 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.12.562112v1?rss=1</link>
<description><![CDATA[
As obligate intracellular pathogens, viruses often activate host metabolic enzymes to supply intermediates that support progeny production. Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme of the salvage NAD+ synthesis, is an interferon-inducible protein that inhibits the replication of several RNA and DNA viruses with unknown mechanism. Here we report that NAMPT restricts herpes simplex virus 1 (HSV-1) replication via phosphoribosyl-hydrolase activity toward key viral structural proteins, independent of NAD+ synthesis. Deep mining of enriched phosphopeptides of HSV-1-infected cells identified phosphoribosylated viral structural proteins, particularly glycoproteins and tegument proteins. Indeed, NAMPT de-phosphoribosylates viral proteins in vitro and in cells. Chimeric and recombinant HSV-1 carrying phosphoribosylation-resistant mutations show that phosphoribosylation promotes the incorporation of structural proteins into HSV-1 virions and subsequent virus entry. Moreover, loss of NAMPT renders mice highly susceptible to HSV-1 infection. The work describes a hidden enzyme activity of a metabolic enzyme in viral infection and host defense, offering a system to interrogate roles of phosphoribosylation in metazoans.
]]></description>
<dc:creator>Feng, S.</dc:creator>
<dc:creator>Xie, N.</dc:creator>
<dc:creator>Liu, Y.</dc:creator>
<dc:creator>Qin, C.</dc:creator>
<dc:creator>Savas, A. C.</dc:creator>
<dc:creator>Wang, T.-y.</dc:creator>
<dc:creator>Li, S.</dc:creator>
<dc:creator>Rao, Y.</dc:creator>
<dc:creator>Shambayate, A.</dc:creator>
<dc:creator>Chou, T.-f.</dc:creator>
<dc:creator>Brenner, C.</dc:creator>
<dc:creator>Huang, C.</dc:creator>
<dc:creator>Feng, P.</dc:creator>
<dc:date>2023-10-16</dc:date>
<dc:identifier>doi:10.1101/2023.10.12.562112</dc:identifier>
<dc:title><![CDATA[The Interferon-inducible NAMPT acts as a protein phosphoribosylase to restrict viral infection]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.16.562538v1?rss=1">
<title>
<![CDATA[
Fluorescence dynamics of lysosomal-related organelle flashing in the intestinal cells of Caenorhabditis elegans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.16.562538v1?rss=1</link>
<description><![CDATA[
The lysosome-related organelles ("gut granules") in the intestinal cells of many nematodes, including Caenorhabditis elegans, play an important role in metabolic and signaling processes, but they have not been fully characterized. We report here a previously undescribed phenomenon in which the autofluorescence of these granules displays a "flash" phenomenon in which fluorescence decreases are preceded by sharp increases in fluorescence intensity that expand into the surrounding area when the granules are stimulated with blue light. Autofluorescent granules are present in the intestinal cells of all six nematode species examined, with differences in morphology and distribution pattern. Five species exhibit the flash phenomenon: Panagrellus redivivus (Clade IV), Steinernema hermaphroditum (Clade IV), C. elegans (Clade V), Oscheius tipulae (Clade V), and Pristionchus pacificus (Clade V). The reaction of the granules to blue light stimulation greatly differs among different developmental stages and may also be dependent on physiological conditions. In addition, even within the same animal, the sensitivity of individual granules differs, with some of the variation associated with other characteristics of the granules, such as their overall location within the intestine. We hypothesize that the differences in response to blue light indicate the existence of different sub-populations of gut granules in nematode intestines, and the visually spectacular dynamic fluorescence phenomenon we describe might provide a handle on their eventual characterization.
]]></description>
<dc:creator>Tan, C.-H.</dc:creator>
<dc:creator>Ding, K.</dc:creator>
<dc:creator>Zhang, M. G.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2023-10-18</dc:date>
<dc:identifier>doi:10.1101/2023.10.16.562538</dc:identifier>
<dc:title><![CDATA[Fluorescence dynamics of lysosomal-related organelle flashing in the intestinal cells of Caenorhabditis elegans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.19.563170v1?rss=1">
<title>
<![CDATA[
Distinct function of Chlamydomonas CTRA-CTR transporters in Cu assimilation and intracellular mobilization 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.19.563170v1?rss=1</link>
<description><![CDATA[
Successful acclimation to copper (Cu) deficiency involves a fine balance between Cu import and export. In the unicellular green alga Chlamydomonas reinhardtii, Cu import is dependent on Copper Response Regulator 1 (CRR1), the master regulator of Cu homeostasis. Among CRR1 target genes are two Cu transporters belonging to the CTR/COPT gene family (CTR1 and CTR2) and a related soluble cysteine-rich protein (CTR3). The ancestor of these green algal proteins was likely acquired from an ancient chytrid and contained conserved cysteine-rich domains (named the CTR-associated domains, CTRA) that are predicted to be involved in Cu acquisition. We show by reverse genetics that Chlamydomonas CTR1 and CTR2 are canonical Cu importers albeit with distinct affinities, while loss of CTR3 did not result in an observable phenotype under the conditions tested. Mutation of CTR1, but not CTR2, recapitulate the poor growth of crr1 in Cu-deficient medium, consistent with a dominant role for CTR1 in high affinity Cu(I) uptake. Notably, the over-accumulation of Cu(I) in Zinc (Zn)-deficiency (20 times the quota) depends on CRR1 and both CTR1 and CTR2. CRR1-dependent activation of CTR gene expression needed for Cu over-accumulation can be bypassed by the provision of excess Cu in the growth medium. Over-accumulated Cu is sequestered into the acidocalcisome but can become remobilized by restoring Zn nutrition. This mobilization is also CRR1-dependent, and requires activation of CTR2 expression, again distinguishing CTR2 from CTR1 and is consistent with the lower substrate affinity of CTR2.
]]></description>
<dc:creator>Strenkert, D.</dc:creator>
<dc:creator>Schmollinger, S.</dc:creator>
<dc:creator>Paruthiyil, S.</dc:creator>
<dc:creator>Brown, B. C.</dc:creator>
<dc:creator>Green, S.</dc:creator>
<dc:creator>Shafer, C. M.</dc:creator>
<dc:creator>Salome, P. A.</dc:creator>
<dc:creator>Nelson, H.</dc:creator>
<dc:creator>Blaby-Haas, C. E.</dc:creator>
<dc:creator>Moseley, J. L.</dc:creator>
<dc:creator>Merchant, S. S.</dc:creator>
<dc:date>2023-10-19</dc:date>
<dc:identifier>doi:10.1101/2023.10.19.563170</dc:identifier>
<dc:title><![CDATA[Distinct function of Chlamydomonas CTRA-CTR transporters in Cu assimilation and intracellular mobilization]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.18.562905v1?rss=1">
<title>
<![CDATA[
T-cell commitment inheritance - an agent-based multi-scale model 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.18.562905v1?rss=1</link>
<description><![CDATA[
T-cell development provides an excellent model system for studying lineage commitment from a multipotent progenitor. The intrathymic development process has been thoroughly studied. The molecular circuitry controlling it has been dissected and the necessary steps like programmed shut off of progenitor genes and T-cell genes upregulation have been revealed. However, the exact timing between decision-making and commitment stage remains unexplored. To this end, we implemented an agent-based multi-scale model to investigate inheritance in early T-cell development. Treating each cell as an agent provides a powerful tool as it tracks each individual cell of a simulated T-cell colony, enabling the construction of lineage trees. Based on the lineage trees, we introduce the concept of the last common ancestors (LCA) of committed cells and analyse their relations, both at single-cell level and population level. In addition to simulating wild-type development, we also conduct knockdown analysis. Our simulations showed that the commitment is a three-step process over several cell generations where a cell is first prepared by a transcriptional switch. This is followed by the loss of the Bcl11b-opposing function two to three generations later which is when the decision to commit is taken. Finally, after another one to two generations, the cell becomes committed by transitioning to the DN2b state. Our results showed that there is inheritance in the commitment mechanism.
]]></description>
<dc:creator>Andersson, E.</dc:creator>
<dc:creator>Rothenberg, E. V.</dc:creator>
<dc:creator>Peterson, C.</dc:creator>
<dc:creator>Olariu, V.</dc:creator>
<dc:date>2023-10-20</dc:date>
<dc:identifier>doi:10.1101/2023.10.18.562905</dc:identifier>
<dc:title><![CDATA[T-cell commitment inheritance - an agent-based multi-scale model]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.20.563366v1?rss=1">
<title>
<![CDATA[
Engineering the soil bacterium Pseudomonas synxantha 2-79 into a ratiometric bioreporter for phosphorus limitation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.20.563366v1?rss=1</link>
<description><![CDATA[
Microbial bioreporters hold promise for addressing challenges in medical and environmental applications. However, the difficulty of ensuring their stable persistence and function within the target environment remains a challenge. One strategy is to integrate information about the host strain and target environment into the design-build-test cycle of the bioreporter itself. Here, we present a case study for such an environmentally-motivated design process by engineering the wheat commensal bacterium Pseudomonas synxantha 2-79 into a ratiometric bioreporter for phosphorus limitation. Comparative analysis showed that an exogenous P-responsive promoter outperformed its native counterparts. This reporter can selectively sense and report phosphorus limitation at plant-relevant concentrations of 25-100 {micro}M without cross-activation from carbon or nitrogen limitation or high cell densities. Its performance is robust over a field-relevant pH range (5.8-8), and it responds only to inorganic phosphorus, even in the presence of common soil organic P. Finally, we used fluorescein-calibrated flow cytometry to assess whether the reporters performance in shaken liquid culture predict its performance in soil, finding that although the reporter is still functional at the bulk level, its variability in performance increases when grown in a soil slurry as compared to planktonic culture, with a fraction of the population not expressing the reporter proteins. Together, our environmentally-aware design process provides an example of how laboratory bioengineering efforts can generate microbes with greater promise to function reliably in their applied contexts.
]]></description>
<dc:creator>Larsson, E. M.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2023-10-21</dc:date>
<dc:identifier>doi:10.1101/2023.10.20.563366</dc:identifier>
<dc:title><![CDATA[Engineering the soil bacterium Pseudomonas synxantha 2-79 into a ratiometric bioreporter for phosphorus limitation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.23.563640v1?rss=1">
<title>
<![CDATA[
Growth couples temporal and spatial fluctuations of tissue properties during morphogenesis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.23.563640v1?rss=1</link>
<description><![CDATA[
Living tissues display fluctuations - random spatial and temporal variations of tissue properties around their reference values - at multiple scales. It is believed that such fluctuations may enable tissues to sense their state or their size. Recent theoretical studies developed specific models of fluctuations in growing tissues and predicted that fluctuations of growth show long-range correlations. Here we elaborated upon these predictions and we tested them using experimental data. We first introduced a minimal model for the fluctuations of any quantity that has some level of temporal persistence or memory, such as concentration of a molecule, local growth rate, or mechanical property. We found that long-range correlations are generic, applying to any such quantity, and that growth couples temporal and spatial fluctuations, through a mechanism that we call  fluctuation stretching -- growth enlarges the lengthscale of variation of this quantity. We then analysed growth data from sepals of the model plant Arabidopsis and we quantified spatial and temporal fluctuations of cell growth using the previously developed Cellular Fourier Transform. Growth appears to have long-range correlations. We compared different genotypes and growth conditions: mutants with lower or higher response to mechanical stress have lower temporal correlations and longer-range spatial correlations than wild-type plants. Finally, we used theoretical predictions to merge experimental data from all conditions and developmental stages into an unifying curve, validating the notion that temporal and spatial fluctuations are coupled by growth. Altogether, our work reveals kinematic constraints on spatiotemporal fluctuations that have an impact on the robustness of morphogenesis.

Significance StatementHow do organs and organisms grow and achieve robust shapes in the face of subcellular and cellular variability? In order to address this outstanding mystery, we investigated the variability of growth at multiple scales and we analysed experimental data from growing plant tissues. Our results support the prediction that tissue expansion couples temporal memory of growth with spatial variability of growth. Our work reveals a constraint on the spatial and temporal variability of growth that may impact the robustness of morphogenesis.
]]></description>
<dc:creator>Fruleux, A.</dc:creator>
<dc:creator>Hong, L.</dc:creator>
<dc:creator>Roeder, A. H. K.</dc:creator>
<dc:creator>Li, C.-B.</dc:creator>
<dc:creator>Boudaoud, A.</dc:creator>
<dc:date>2023-10-25</dc:date>
<dc:identifier>doi:10.1101/2023.10.23.563640</dc:identifier>
<dc:title><![CDATA[Growth couples temporal and spatial fluctuations of tissue properties during morphogenesis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.24.563881v1?rss=1">
<title>
<![CDATA[
TRILL: Orchestrating Modular Deep-Learning Workflows for Democratized, Scalable Protein Analysis and Engineering 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.24.563881v1?rss=1</link>
<description><![CDATA[
AO_SCPLOWBSTRACTC_SCPLOWDeep-learning models have been rapidly adopted by many fields, partly due to the deluge of data humanity has amassed. In particular, the petabases of biological sequencing data enable the unsupervised training of protein language models that learn the "language of life." However, due to their prohibitive size and complexity, contemporary deep-learning models are often unwieldy, especially for scientists with limited machine learning backgrounds. TRILL (TRaining and Inference using the Language of Life) is a platform for creative protein design and discovery. Leveraging several state-of-the-art models such as ESM-2, DiffDock, and RFDiffusion, TRILL allows researchers to generate novel proteins, predict 3-D structures, extract high-dimensional representations of proteins, functionally classify proteins and more. What sets TRILL apart is its ability to enable complex pipelines by chaining together models and effectively merging the capabilities of different models to achieve a sum greater than its individual parts. Whether using Google Colab with one GPU or a supercomputer with hundreds, TRILL allows scientists to effectively utilize models with millions to billions of parameters by using optimized training strategies such as ZeRO-Offload and distributed data parallel. Therefore, TRILL not only bridges the gap between complex deep-learning models and their practical application in the field of biology, but also simplifies the orchestration of these models into comprehensive workflows, democratizing access to powerful methods. Documentation: https://trill.readthedocs.io/en/latest/home.html.
]]></description>
<dc:creator>Martinez, Z. A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:creator>Thomson, M. W.</dc:creator>
<dc:date>2023-10-27</dc:date>
<dc:identifier>doi:10.1101/2023.10.24.563881</dc:identifier>
<dc:title><![CDATA[TRILL: Orchestrating Modular Deep-Learning Workflows for Democratized, Scalable Protein Analysis and Engineering]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.25.564019v1?rss=1">
<title>
<![CDATA[
Metabolic similarity and the predictability of microbial community assembly 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.25.564019v1?rss=1</link>
<description><![CDATA[
AbstractWhen microbial communities form, their composition is shaped by selective pressures imposed by the environment. Can we predict which communities will assemble under different environmental conditions? Here, we hypothesize that quantitative similarities in metabolic traits across metabolically similar environments lead to predictable similarities in community composition. To that end, we measured the growth rate and by-product profile of a library of proteobacterial strains in a large number of single nutrient environments. We found that growth rates and secretion profiles were positively correlated across environments when the supplied substrate was metabolically similar. By analyzing hundreds of in-vitro communities experimentally assembled in an array of different synthetic environments, we then show that metabolically similar substrates select for taxonomically similar communities. These findings lead us to propose and then validate a comparative approach for quantitatively predicting the effects of novel substrates on the composition of complex microbial consortia.
]]></description>
<dc:creator>Vila, J. C. C.</dc:creator>
<dc:creator>Goldford, J.</dc:creator>
<dc:creator>Estrela, S.</dc:creator>
<dc:creator>Bajic, D.</dc:creator>
<dc:creator>Sanchez-Gorostiaga, A.</dc:creator>
<dc:creator>Damian-Serrano, A.</dc:creator>
<dc:creator>Lu, N.</dc:creator>
<dc:creator>Marsland, R.</dc:creator>
<dc:creator>Rebolleda-Gomez, M.</dc:creator>
<dc:creator>Mehta, P.</dc:creator>
<dc:creator>Sanchez, A.</dc:creator>
<dc:date>2023-10-28</dc:date>
<dc:identifier>doi:10.1101/2023.10.25.564019</dc:identifier>
<dc:title><![CDATA[Metabolic similarity and the predictability of microbial community assembly]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.30.564641v1?rss=1">
<title>
<![CDATA[
Uncultivated DPANN archaea are ubiquitous inhabitants of global oxygen deficient zones with diverse metabolic potential 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.30.564641v1?rss=1</link>
<description><![CDATA[
Archaea belonging to the DPANN superphylum have been found within an expanding number of environments and perform a variety of biogeochemical roles, including contributing to carbon, sulfur, and nitrogen cycling. Generally characterized by ultrasmall cell sizes and reduced genomes, DPANN archaea may form mutualistic, commensal, or parasitic interactions with various archaeal and bacterial hosts, influencing the ecology and functioning of microbial communities. While DPANN archaea reportedly comprise 15-26% of the archaeal community within marine oxygen deficient zone (ODZ) water columns, little is known about their metabolic capabilities in these ecosystems. We report 33 novel metagenome-assembled genomes belonging to DPANN phyla Nanoarchaeota, Pacearchaeota, Woesarchaeota, Undinarchaeota, Iainarchaeota, and SpSt-1190 from pelagic ODZs in the Eastern Tropical North Pacific and Arabian Sea. We find these archaea to be permanent, stable residents of all 3 major ODZs only within anoxic depths, comprising up to 1% of the total microbial community and up to 25-50% of archaea. ODZ DPANN appear capable of diverse metabolic functions, including fermentation, organic carbon scavenging, and the cycling of sulfur, hydrogen, and methane. Within a majority of ODZ DPANN, we identify a gene homologous to nitrous oxide reductase. Modeling analyses indicate the feasibility of a nitrous oxide reduction metabolism for host-attached symbionts, and the small genome sizes and reduced metabolic capabilities of most DPANN MAGs suggest host-associated lifestyles within ODZs.

ImportanceArchaea from the DPANN superphylum have diverse metabolic capabilities and participate in multiple biogeochemical cycles. While metagenomics and enrichments have revealed that many DPANN are characterized by ultrasmall genomes, few biosynthetic genes, and episymbiotic lifestyles, much remains unknown about their biology. We report 33 new DPANN metagenome-assembled genomes originating from the 3 global marine oxygen deficient zones (ODZs), the first from these regions. We survey DPANN abundance and distribution within the ODZ water column, investigate their biosynthetic capabilities, and report potential roles in the cycling of organic carbon, methane, and nitrogen. We test the hypothesis that nitrous oxide reductases found within several ODZ DPANN genomes may enable ultrasmall episymbionts to serve as nitrous oxide consumers when attached to a host nitrous oxide producer. Our results indicate DPANN archaea as ubiquitous residents within the anoxic core of ODZs with the potential to produce or consume key compounds.
]]></description>
<dc:creator>Zhang, I. H.</dc:creator>
<dc:creator>Borer, B.</dc:creator>
<dc:creator>Zhao, R.</dc:creator>
<dc:creator>Wilbert, S.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:creator>Babbin, A. R.</dc:creator>
<dc:date>2023-10-30</dc:date>
<dc:identifier>doi:10.1101/2023.10.30.564641</dc:identifier>
<dc:title><![CDATA[Uncultivated DPANN archaea are ubiquitous inhabitants of global oxygen deficient zones with diverse metabolic potential]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-10-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.10.30.564854v1?rss=1">
<title>
<![CDATA[
Principles of Computation by Competitive Protein Dimerization Networks 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.10.30.564854v1?rss=1</link>
<description><![CDATA[
Many biological signaling pathways employ proteins that competitively dimerize in diverse combinations. These dimerization networks can perform biochemical computations, in which the concentrations of monomers (inputs) determine the concentrations of dimers (outputs). Despite their prevalence, little is known about the range of input-output computations that dimerization networks can perform (their "expressivity") and how it depends on network size and connectivity. Using a systematic computational approach, we demonstrate that even small dimerization networks (3-6 monomers) are expressive, performing diverse multi-input computations. Further, dimerization networks are versatile, performing different computations when their protein components are expressed at different levels, such as in different cell types. Remarkably, individual networks with random interaction affinities, when large enough ([&ge;]8 proteins), can perform nearly all ([~]90%) potential one-input network computations merely by tuning their monomer expression levels. Thus, even the simple process of competitive dimerization provides a powerful architecture for multi-input, cell-type-specific signal processing.

Graphical Abstract

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/564854v2_ufig1.gif" ALT="Figure 1">
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]]></description>
<dc:creator>Parres-Gold, J.</dc:creator>
<dc:creator>Levine, M.</dc:creator>
<dc:creator>Emert, B.</dc:creator>
<dc:creator>Stuart, A.</dc:creator>
<dc:creator>Elowitz, M.</dc:creator>
<dc:date>2023-11-02</dc:date>
<dc:identifier>doi:10.1101/2023.10.30.564854</dc:identifier>
<dc:title><![CDATA[Principles of Computation by Competitive Protein Dimerization Networks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.01.565073v1?rss=1">
<title>
<![CDATA[
Neuropeptide Signaling Is Required To Implement A Line Attractor Encoding A Persistent Internal Behavioral State 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.01.565073v1?rss=1</link>
<description><![CDATA[
Internal states drive survival behaviors, but their neural implementation is not well understood. Recently we identified a line attractor in the ventromedial hypothalamus (VMH) that represents an internal state of aggressiveness. Line attractors can be implemented by recurrent connectivity and/or neuromodulatory signaling, but evidence for the latter is scant. Here we show that neuropeptidergic signaling is necessary for line attractor dynamics in this system, using a novel approach that integrates cell type-specific, anatomically restricted CRISPR/Cas9-based gene editing with microendoscopic calcium imaging. Co-disruption of receptors for oxytocin and vasopressin in adult VMH Esr1+ neurons that control aggression suppressed attack, reduced persistent neural activity and eliminated line attractor dynamics, while only modestly impacting neural activity and sex- or behavior-tuning. These data identify a requisite role for neuropeptidergic signaling in implementing a behaviorally relevant line attractor. Our approach should facilitate mechanistic studies in neuroscience that bridge different levels of biological function and abstraction.
]]></description>
<dc:creator>Mountoufaris, G.</dc:creator>
<dc:creator>Nair, A.</dc:creator>
<dc:creator>Yang, B.</dc:creator>
<dc:creator>Kim, D.-W.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:date>2023-11-02</dc:date>
<dc:identifier>doi:10.1101/2023.11.01.565073</dc:identifier>
<dc:title><![CDATA[Neuropeptide Signaling Is Required To Implement A Line Attractor Encoding A Persistent Internal Behavioral State]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.06.565773v1?rss=1">
<title>
<![CDATA[
Catalytic and non-catalytic functions of DNA polymerase kappa in translesion DNA synthesis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.06.565773v1?rss=1</link>
<description><![CDATA[
Translesion DNA synthesis (TLS) is an essential process that allows cells to bypass lesions encountered during DNA replication and is emerging as a primary target of chemotherapy. Among vertebrate DNA polymerases, polymerase kappa (Pol() has the unique ability to bypass minor groove DNA adducts in vitro. However, Pol(is also required for cells to overcome major groove DNA adducts but the basis of this requirement is unclear. Here, we combine CRISPR base editor screening technology in human cells with TLS analysis of defined DNA lesions in Xenopus egg extracts to unravel the functions and regulations of Pol(during lesion bypass. Strikingly, we show that Pol(has two main functions during TLS, which are differentially regulated via Rev1 binding. On the one hand, Pol(is essential to replicate across minor groove DNA lesions in a process that depends on PCNA ubiquitylation but is independent of Rev1. On the other hand, via its cooperative interaction with Rev1 and ubiquitylated PCNA, Pol(stabilizes the Rev1-Pol(extension complex on DNA to allow extension past major groove DNA lesions and abasic sites, in a process that is independent of Pol(catalytic activity. Together, our work identifies catalytic and non-catalytic functions of Pol(in TLS and reveals important regulatory mechanisms underlying the unique domain architecture present at the C-terminal end of Y-family TLS polymerases.
]]></description>
<dc:creator>Selles-Baiget, S.</dc:creator>
<dc:creator>Ambjorn, S. M.</dc:creator>
<dc:creator>Carli, A.</dc:creator>
<dc:creator>Hendriks, I. A.</dc:creator>
<dc:creator>Gallina, I.</dc:creator>
<dc:creator>Davey, N. E.</dc:creator>
<dc:creator>Benedict, B.</dc:creator>
<dc:creator>Meeusen, B.</dc:creator>
<dc:creator>Hertz, E. P. T.</dc:creator>
<dc:creator>Slappendel, L.</dc:creator>
<dc:creator>Semlow, D.</dc:creator>
<dc:creator>Gadi, S. A.</dc:creator>
<dc:creator>Sturla, S.</dc:creator>
<dc:creator>Nielsen, M. L.</dc:creator>
<dc:creator>Nilsson, J.</dc:creator>
<dc:creator>Miller, T. C. R.</dc:creator>
<dc:creator>Duxin, J. P.</dc:creator>
<dc:date>2023-11-06</dc:date>
<dc:identifier>doi:10.1101/2023.11.06.565773</dc:identifier>
<dc:title><![CDATA[Catalytic and non-catalytic functions of DNA polymerase kappa in translesion DNA synthesis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.07.566113v1?rss=1">
<title>
<![CDATA[
Molecular identification of a peroxidase gene controlling body size in the entomopathogenic nematode Steinernema hermaphroditum 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.07.566113v1?rss=1</link>
<description><![CDATA[
The entomopathogenic nematode Steinernema hermaphroditum was recently rediscovered and is being developed as a genetically tractable experimental system for the study of previously unexplored biology, including parasitism of its insect hosts and mutualism with its bacterial endosymbiont Xenorhabdus griffiniae. Through whole-genome re-sequencing and genetic mapping we have for the first time molecularly identified the gene responsible for a mutationally defined phenotypic locus in an entomopathogenic nematode. In the process we observed an unexpected mutational spectrum following EMS mutagenesis in this species. We find that the ortholog of the essential C. elegans peroxidase gene skpo-2 controls body size and shape in S. hermaphroditum. We confirmed this identification by inactivating the gene using CRISPR-Cas9. We propose that the identification of skpo-2 will accelerate gene targeting in other Steinernema entomopathogenic nematodes used commercially in pest control, as skpo-2 is X-linked and males hemizygous for loss of its function can mate, making skpo-2 an easily recognized and maintained marker for use in co-CRISPR.
]]></description>
<dc:creator>Schwartz, H. T. T.</dc:creator>
<dc:creator>Tan, C.-H.</dc:creator>
<dc:creator>Peraza, J.</dc:creator>
<dc:creator>Raymundo, K. L. T.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2023-11-10</dc:date>
<dc:identifier>doi:10.1101/2023.11.07.566113</dc:identifier>
<dc:title><![CDATA[Molecular identification of a peroxidase gene controlling body size in the entomopathogenic nematode Steinernema hermaphroditum]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.10.566490v1?rss=1">
<title>
<![CDATA[
Abstract representations emerge in human hippocampal neurons during inference behavior 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.10.566490v1?rss=1</link>
<description><![CDATA[
Humans have the remarkable cognitive capacity to rapidly adapt to changing environments. Central to this capacity is the ability to form high-level, abstract representations that take advantage of regularities in the world to support generalization1. However, little is known about how these representations are encoded in populations of neurons, how they emerge through learning, and how they relate to behavior2,3. Here we characterized the representational geometry of populations of neurons (single-units) recorded in the hippocampus, amygdala, medial frontal cortex, and ventral temporal cortex of neurosurgical patients who are performing an inferential reasoning task. We find that only the neural representations formed in the hippocampus simultaneously encode multiple task variables in an abstract, or disentangled, format. This representational geometry is uniquely observed after patients learn to perform inference, and consisted of disentangled directly observable and discovered latent task variables. Interestingly, learning to perform inference by trial and error or through verbal instructions led to the formation of hippocampal representations with similar geometric properties. The observed relation between representational format and inference behavior suggests that abstract/disentangled representational geometries are important for complex cognition.
]]></description>
<dc:creator>Courellis, H. S.</dc:creator>
<dc:creator>Minxha, J.</dc:creator>
<dc:creator>Ramirez Cardenas, A.</dc:creator>
<dc:creator>Kimmel, D. L.</dc:creator>
<dc:creator>Reed, C. M.</dc:creator>
<dc:creator>Valiante, T. A.</dc:creator>
<dc:creator>Salzman, C. D.</dc:creator>
<dc:creator>Mamelak, A. N.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:creator>Fusi, S.</dc:creator>
<dc:creator>Rutishauser, U.</dc:creator>
<dc:date>2023-11-11</dc:date>
<dc:identifier>doi:10.1101/2023.11.10.566490</dc:identifier>
<dc:title><![CDATA[Abstract representations emerge in human hippocampal neurons during inference behavior]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.09.566364v1?rss=1">
<title>
<![CDATA[
Ultrasonic reporters of calcium for deep tissue imaging of cellular signals 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.09.566364v1?rss=1</link>
<description><![CDATA[
Calcium imaging has enabled major biological discoveries. However, the scattering of light by tissue limits the use of standard fluorescent calcium indicators in living animals. To address this limitation, we introduce the first genetically encoded ultrasonic reporter of calcium (URoC). Based on a unique class of air-filled protein nanostructures called gas vesicles, we engineered URoC to produce elevated nonlinear ultrasound signal upon binding to calcium ions. With URoC expressed in mammalian cells, we demonstrate noninvasive ultrasound imaging of calcium signaling in vivo during drug-induced receptor activation. URoC brings the depth and resolution advantages of ultrasound to the in vivo imaging of dynamic cellular function and paves the way for acoustic biosensing of a broader variety of biological signals.
]]></description>
<dc:creator>Jin, Z.</dc:creator>
<dc:creator>Lakshmanan, A.</dc:creator>
<dc:creator>Zhang, R.</dc:creator>
<dc:creator>Tran, T. A.</dc:creator>
<dc:creator>Rabut, C.</dc:creator>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Duan, M.</dc:creator>
<dc:creator>Hurt, R. C.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Yao, Y.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2023-11-12</dc:date>
<dc:identifier>doi:10.1101/2023.11.09.566364</dc:identifier>
<dc:title><![CDATA[Ultrasonic reporters of calcium for deep tissue imaging of cellular signals]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.14.567096v1?rss=1">
<title>
<![CDATA[
Genetically dissecting the electron transport chain of a soil bacterium reveals a generalizable mechanism for biological phenazine-1-carboxylic acid oxidation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.14.567096v1?rss=1</link>
<description><![CDATA[
The capacity for bacterial extracellular electron transfer via secreted metabolites is widespread in natural, clinical, and industrial environments. Recently, we discovered biological oxidation of phenazine-1-carboxylic acid (PCA), the first example of biological regeneration of a naturally produced extracellular electron shuttle. However, it remained unclear how PCA oxidation was catalyzed. Here, we report the mechanism, which we uncovered by genetically perturbing the branched electron transport chain (ETC) of the soil isolate Citrobacter portucalensis MBL. Biological PCA oxidation is coupled to anaerobic respiration with nitrate, fumarate, dimethyl sulfoxide, or trimethylamine-N-oxide as terminal electron acceptors. Genetically inactivating the catalytic subunits for all redundant complexes for a given terminal electron acceptor abolishes PCA oxidation. In the absence of quinones, PCA can still donate electrons to certain terminal reductases, albeit much less efficiently. In C. portucalensis MBL, PCA oxidation is largely driven by flux through the ETC, which suggests a generalizable mechanism that may be employed by any anaerobically respiring bacterium with an accessible cytoplasmic membrane. This model is supported by analogous genetic experiments during nitrate respiration by Pseudomonas aeruginosa.

Author summaryMany bacteria have extremely flexible metabolisms, and we are only beginning to understand how they manifest in the environment. Our study focuses on the role of phenazine-1-carboxylic acid (PCA), a molecule that some bacteria synthesize and secrete into their surroundings. PCA is an "extracellular electron shuttle," a molecule that readily transfers electrons between cells and oxidizing/reducing compounds or other cells. Until our investigation, the role of PCA electron-shuttling had only been studied in one direction: how it takes electrons away from cells, and the effect this has on their viability. Here we present a detailed account of the opposite process and its mechanism: what happens when PCA delivers electrons to cells? Our findings indicate that this previously underappreciated process is generalizable to any anaerobically respiring bacterium. Consequently, we expect that electron donation by PCA is widespread in environments where PCA is plentiful and oxygen is sparse, such as in some agricultural soils. The universality of the extracellular electron shuttle oxidation mechanism we describe for PCA suggests that it should also occur with similar small molecules, of which there are thousands, deepening the implication that this is a significant process in the environment and motivating further research into its consequences.
]]></description>
<dc:creator>Tsypin, L. M. Z.</dc:creator>
<dc:creator>Saunders, S. H.</dc:creator>
<dc:creator>Chen, A. W.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2023-11-14</dc:date>
<dc:identifier>doi:10.1101/2023.11.14.567096</dc:identifier>
<dc:title><![CDATA[Genetically dissecting the electron transport chain of a soil bacterium reveals a generalizable mechanism for biological phenazine-1-carboxylic acid oxidation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.14.566368v1?rss=1">
<title>
<![CDATA[
Simultaneous single-cell calcium imaging of neuronal population activity and brain-wide BOLD fMRI 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.14.566368v1?rss=1</link>
<description><![CDATA[
Blood Oxygen Level-Dependent (BOLD) functional Magnetic Resonance Imaging (fMRI) allows for non-invasive, indirect recordings of neural activity across the whole brain in both humans and animals. However, the relationship between the local neural population activity and the vascular activity is not completely understood. To investigate this relationship, we present a novel MRI compatible single-photon microscope capable of measuring cellular resolution Ca2+ activity of genetically defined neurons during whole-brain BOLD fMRI in awake behaving mice. Using this combined imaging approach, we found a difference in activity patterns between cells which was dependent on their location with respect to the vasculature. Notably, neurons near the vasculature showed pronounced negative activity during contralateral whisker movements at 3 Hz. In a second proof of concept experiment, we demonstrate the potential of recording both local neural activities, like those in the barrel field (SSp-bfd), and BOLD fMRI readings from interlinked brain regions. In sum, the presented technological advancement paves the way for studies examining the interplay between local brain circuits and overarching brain functions. In addition, the new approach enhances our understanding of the vascular BOLD fMRI signal, providing insights into the determinants of local neurovascular functions and the brains organizational framework across various scales.
]]></description>
<dc:creator>Ubaghs, R. L. E. M.</dc:creator>
<dc:creator>Boehringer, R.</dc:creator>
<dc:creator>Marks, M.</dc:creator>
<dc:creator>Hesse, H. K.</dc:creator>
<dc:creator>Yanik, M. F.</dc:creator>
<dc:creator>Zerbi, V.</dc:creator>
<dc:creator>Grewe, B. F.</dc:creator>
<dc:date>2023-11-16</dc:date>
<dc:identifier>doi:10.1101/2023.11.14.566368</dc:identifier>
<dc:title><![CDATA[Simultaneous single-cell calcium imaging of neuronal population activity and brain-wide BOLD fMRI]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.15.567056v1?rss=1">
<title>
<![CDATA[
Fast and scalable querying of eukaryotic linear motifs with gget elm 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.15.567056v1?rss=1</link>
<description><![CDATA[
MotivationEukaryotic linear motifs (ELMs), or Short Linear Motifs (SLiMs), are protein interaction modules that play an essential role in cellular processes and signaling networks and are often involved in diseases like cancer. The ELM database is a collection of manually curated motif knowledge from scientific papers. It has become a crucial resource for cataloging motif biology and recognizing candidate ELMs in novel amino acid sequences. Users can search amino acid sequences or UniProt IDs on the ELM resource web interface. However, as with many web services, there are limitations in the swift processing of large-scale queries through the ELM web interface or API calls, and, therefore, integration into protein function analysis pipelines is limited.

ResultsTo allow swift, large-scale motif analyses on protein sequences using ELMs curated on the ELM database, we have developed a Python and command line tool, gget elm, which relies on local computations for efficiently finding candidate ELMs in user-submitted amino acid sequences and UniProt identifiers. gget elm increases accessibility to the information stored in the ELM database and allows scalable searches for motif-mediated interaction sites in the amino acid sequences.

Availability and implementationThe manual and source code are available at https://github.com/pachterlab/gget.
]]></description>
<dc:creator>Luebbert, L.</dc:creator>
<dc:creator>Hoang, C.</dc:creator>
<dc:creator>Kumar, M.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2023-11-17</dc:date>
<dc:identifier>doi:10.1101/2023.11.15.567056</dc:identifier>
<dc:title><![CDATA[Fast and scalable querying of eukaryotic linear motifs with gget elm]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.17.567630v1?rss=1">
<title>
<![CDATA[
A Foundation Model for Cell Segmentation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.17.567630v1?rss=1</link>
<description><![CDATA[
Cells are a fundamental unit of biological organization, and identifying them in imaging data - cell segmentation - is a critical task for various cellular imaging experiments. While deep learning methods have led to substantial progress on this problem, most models are specialist models that work well for specific domains but cannot be applied across domains or scale well with large amounts of data. In this work, we present CellSAM, a universal model for cell segmentation that generalizes across diverse cellular imaging data. CellSAM builds on top of the Segment Anything Model (SAM) by developing a prompt engineering approach for mask generation. We train an object detector, CellFinder, to automatically detect cells and prompt SAM to generate segmentations. We show that this approach allows a single model to achieve human-level performance for segmenting images of mammalian cells, yeast, and bacteria collected across various imaging modalities. We show that CellSAM has strong zero-shot performance and can be improved with a few examples via few-shot learning. Additionally, we demonstrate how CellSAM can be applied across diverse bioimage analysis workflows. A deployed version of CellSAM is available at https://cellsam.deepcell.org/.
]]></description>
<dc:creator>Israel, U.</dc:creator>
<dc:creator>Marks, M.</dc:creator>
<dc:creator>Dilip, R.</dc:creator>
<dc:creator>Li, Q.</dc:creator>
<dc:creator>Schwartz, M. S.</dc:creator>
<dc:creator>Pradhan, E.</dc:creator>
<dc:creator>Pao, E.</dc:creator>
<dc:creator>Li, S.</dc:creator>
<dc:creator>Pearson-Goulart, A.</dc:creator>
<dc:creator>Perona, P.</dc:creator>
<dc:creator>Gkioxari, G.</dc:creator>
<dc:creator>Barnowski, R.</dc:creator>
<dc:creator>Yue, Y.</dc:creator>
<dc:creator>Van Valen, D. A.</dc:creator>
<dc:date>2023-11-20</dc:date>
<dc:identifier>doi:10.1101/2023.11.17.567630</dc:identifier>
<dc:title><![CDATA[A Foundation Model for Cell Segmentation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.20.567935v1?rss=1">
<title>
<![CDATA[
Updates to the Alliance of Genome Resources Central Infrastructure 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.20.567935v1?rss=1</link>
<description><![CDATA[
The Alliance of Genome Resources (Alliance) is an extensible coalition of knowledgebases focused on the genetics and genomics of intensively-studied model organisms. The Alliance is organized as individual knowledge centers with strong connections to their research communities and a centralized software infrastructure, discussed here. Model organisms currently represented in the Alliance are budding yeast, C. elegans, Drosophila, zebrafish, frog, laboratory mouse, laboratory rat, and the Gene Ontology Consortium. The project is in a rapid development phase to harmonize knowledge, store it, analyze it, and present it to the community through a web portal, direct downloads, and APIs. Here we focus on developments over the last two years. Specifically, we added and enhanced tools for browsing the genome (JBrowse), downloading sequences, mining complex data (AllianceMine), visualizing pathways, full-text searching of the literature (Textpresso), and sequence similarity searching (SequenceServer). We enhanced existing interactive data tables and added an interactive table of paralogs to complement our representation of orthology. To support individual model organism communities, we implemented species-specific "landing pages" and will add disease-specific portals soon; in addition, we support a common community forum implemented in Discourse. We describe our progress towards a central persistent database to support curation, the data modeling that underpins harmonization, and progress towards a state-of-the art literature curation system with integrated Artificial Intelligence and Machine Learning (AI/ML).
]]></description>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Alliance of Genome Resources Consortium,</dc:creator>
<dc:date>2023-11-22</dc:date>
<dc:identifier>doi:10.1101/2023.11.20.567935</dc:identifier>
<dc:title><![CDATA[Updates to the Alliance of Genome Resources Central Infrastructure]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.21.568164v1?rss=1">
<title>
<![CDATA[
kallisto, bustools, and kb-python for quantifying bulk, single-cell, and single-nucleus RNA-seq 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.21.568164v1?rss=1</link>
<description><![CDATA[
The term "RNA-seq" refers to a collection of assays based on sequencing experiments that involve quantifying RNA species from bulk tissue, from single cells, or from single nuclei. The kallisto, bustools, and kb-python programs are free, open-source software tools for performing this analysis that together can produce gene expression quantification from raw sequencing reads. The quantifications can be individualized for multiple cells, multiple samples, or both. Additionally, these tools allow gene expression values to be classified as originating from nascent RNA species or mature RNA species, making this workflow amenable to both cell-based and nucleus-based assays. This protocol describes in detail how to use kallisto and bustools in conjunction with a wrapper, kb-python, to preprocess RNA-seq data.
]]></description>
<dc:creator>Sullivan, D. K.</dc:creator>
<dc:creator>Min, K. H.</dc:creator>
<dc:creator>Hjörleifsson, K. E.</dc:creator>
<dc:creator>Luebbert, L.</dc:creator>
<dc:creator>Holley, G.</dc:creator>
<dc:creator>Moses, L.</dc:creator>
<dc:creator>Gustafsson, J.</dc:creator>
<dc:creator>Bray, N. L.</dc:creator>
<dc:creator>Pimentel, H.</dc:creator>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Melsted, P.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2023-11-22</dc:date>
<dc:identifier>doi:10.1101/2023.11.21.568164</dc:identifier>
<dc:title><![CDATA[kallisto, bustools, and kb-python for quantifying bulk, single-cell, and single-nucleus RNA-seq]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.22.568217v1?rss=1">
<title>
<![CDATA[
Spatial transcriptomics defines injury-specific microenvironments in the adult mouse kidney and novel cellular interactions in regeneration and disease 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.22.568217v1?rss=1</link>
<description><![CDATA[
Kidney injury disrupts the intricate renal architecture and triggers limited regeneration, and injury-invoked inflammation and fibrosis. Deciphering molecular pathways and cellular interactions driving these processes is challenging due to the complex renal architecture. Here, we applied single cell spatial transcriptomics to examine ischemia-reperfusion injury in the mouse kidney. Spatial transcriptomics revealed injury-specific and spatially-dependent gene expression patterns in distinct cellular microenvironments within the kidney and predicted Clcf1-Crfl1 in a molecular interplay between persistently injured proximal tubule cells and neighboring fibroblasts. Immune cell types play a critical role in organ repair. Spatial analysis revealed cellular microenvironments resembling early tertiary lymphoid structures and identified associated molecular pathways. Collectively, this study supports a focus on molecular interactions in cellular microenvironments to enhance understanding of injury, repair and disease.

One-Sentence Summary: Spatial transcriptomics predicted a molecular interplay amongst neighboring cell-types in the injured mammalian kidney

Main Text:
]]></description>
<dc:creator>Polonsky, M.</dc:creator>
<dc:creator>Gerhardt, L. M. S.</dc:creator>
<dc:creator>Yun, J.</dc:creator>
<dc:creator>Koppitch, K.</dc:creator>
<dc:creator>Colon, K.</dc:creator>
<dc:creator>Amrhein, H.</dc:creator>
<dc:creator>Zheng, S.</dc:creator>
<dc:creator>Yuan, G.-C.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:creator>McMahon, A. P.</dc:creator>
<dc:date>2023-11-22</dc:date>
<dc:identifier>doi:10.1101/2023.11.22.568217</dc:identifier>
<dc:title><![CDATA[Spatial transcriptomics defines injury-specific microenvironments in the adult mouse kidney and novel cellular interactions in regeneration and disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.28.569054v1?rss=1">
<title>
<![CDATA[
Role of a holo-insertase complex in the biogenesis of biophysically diverse ER membrane proteins 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.28.569054v1?rss=1</link>
<description><![CDATA[
Mammalian membrane proteins perform essential physiologic functions that rely on their accurate insertion and folding at the endoplasmic reticulum (ER). Using forward and arrayed genetic screens, we systematically studied the biogenesis of a panel of membrane proteins, including several G-protein coupled receptors (GPCRs). We observed a central role for the insertase, the ER membrane protein complex (EMC), and developed a dual-guide approach to identify genetic modifiers of the EMC. We found that the back of sec61 (BOS) complex, a component of the  multipass translocon, was a physical and genetic interactor of the EMC. Functional and structural analysis of the EMC*BOS holocomplex showed that characteristics of a GPCRs soluble domain determine its biogenesis pathway. In contrast to prevailing models, no single insertase handles all substrates. We instead propose a unifying model for coordination between the EMC, multipass translocon, and Sec61 for biogenesis of diverse membrane proteins in human cells.
]]></description>
<dc:creator>Page, K. R.</dc:creator>
<dc:creator>Nguyen, V. N.</dc:creator>
<dc:creator>Pleiner, T.</dc:creator>
<dc:creator>Tomaleri, G. P.</dc:creator>
<dc:creator>Wang, M. L.</dc:creator>
<dc:creator>Guna, A.</dc:creator>
<dc:creator>Wang, T.-Y.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:date>2023-11-29</dc:date>
<dc:identifier>doi:10.1101/2023.11.28.569054</dc:identifier>
<dc:title><![CDATA[Role of a holo-insertase complex in the biogenesis of biophysically diverse ER membrane proteins]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.28.569094v1?rss=1">
<title>
<![CDATA[
Multi-ContrastiveVAE disentangles perturbation effects in single cell images from optical pooled screens 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.28.569094v1?rss=1</link>
<description><![CDATA[
Optical pooled screens (OPS) enable comprehensive and cost-effective interrogation of gene function by measuring microscopy images of millions of cells across thousands of perturbations. However, the analysis of OPS data still mainly relies on hand-crafted features, even though these are difficult to deploy across complex data sets. This is because most unsupervised feature extraction methods based on neural networks (such as auto-encoders) have difficulty isolating the effect of perturbations from the natural variations across cells and experimental batches. Here, we propose a contrastive analysis framework that can more effectively disentangle the phenotypes caused by perturbation from natural cell-cell heterogeneity present in an unperturbed cell population. We demonstrate this approach by analyzing a large data set of over 30 million cells imaged across more than 5, 000 genetic perturbations, showing that our method significantly outperforms traditional approaches in generating biologically-informative embeddings and mitigating technical artifacts. Furthermore, the interpretable part of our model distinguishes perturbations that generate novel phenotypes from the ones that only shift the distribution of existing phenotypes. Our approach can be readily applied to other small-molecule and genetic perturbation data sets with highly multiplexed images, enhancing the efficiency and precision in identifying and interpreting perturbation-specific phenotypic patterns, paving the way for deeper insights and discoveries in OPS analysis.
]]></description>
<dc:creator>Wang, Z. J.</dc:creator>
<dc:creator>Lopez, R.</dc:creator>
<dc:creator>Huetter, J.-C.</dc:creator>
<dc:creator>Kudo, T.</dc:creator>
<dc:creator>Yao, H.</dc:creator>
<dc:creator>Hanslovsky, P.</dc:creator>
<dc:creator>Hoeckendorf, B.</dc:creator>
<dc:creator>Regev, A.</dc:creator>
<dc:date>2023-11-29</dc:date>
<dc:identifier>doi:10.1101/2023.11.28.569094</dc:identifier>
<dc:title><![CDATA[Multi-ContrastiveVAE disentangles perturbation effects in single cell images from optical pooled screens]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-11-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.29.569306v1?rss=1">
<title>
<![CDATA[
FAIR Header Reference genome: A TRUSTworthy standard 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.29.569306v1?rss=1</link>
<description><![CDATA[
The lack of interoperable data standards among reference genome data-sharing platforms inhibits cross-platform analysis while increasing the risk of data provenance loss. Here, we describe the FAIR-bioHeaders Reference genome (FHR), a metadata standard guided by the principles of Findability, Accessibility, Interoperability, and Reuse (FAIR) in addition to the principles of Transparency, Responsibility, User focus, Sustainability, and Technology (TRUST). The objective of FHR is to provide an extensive set of data serialisation methods and minimum data field requirements while still maintaining extensibility, flexibility, and expressivity in an increasingly decentralised genomic data ecosystem. The effort needed to implement FHR is low; FHRs design philosophy ensures easy implementation while retaining the benefits gained from recording both machine and human-readable provenance.
]]></description>
<dc:creator>Wright, A.</dc:creator>
<dc:creator>Wilkinson, M. D.</dc:creator>
<dc:creator>Mungall, C.</dc:creator>
<dc:creator>Cain, S.</dc:creator>
<dc:creator>Richards, S.</dc:creator>
<dc:creator>Sternberg, P.</dc:creator>
<dc:creator>Provin, E.</dc:creator>
<dc:creator>Jacobs, J. L.</dc:creator>
<dc:creator>Geib, S.</dc:creator>
<dc:creator>Raciti, D.</dc:creator>
<dc:creator>Yook, K.</dc:creator>
<dc:creator>Stein, L.</dc:creator>
<dc:creator>Molik, D. C.</dc:creator>
<dc:date>2023-12-01</dc:date>
<dc:identifier>doi:10.1101/2023.11.29.569306</dc:identifier>
<dc:title><![CDATA[FAIR Header Reference genome: A TRUSTworthy standard]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-12-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.11.30.569486v1?rss=1">
<title>
<![CDATA[
Bioorthogonal labeling enables in situ fluorescence imaging of expressed gas vesicle nanostructures 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.11.30.569486v1?rss=1</link>
<description><![CDATA[
Gas vesicles (GVs) are proteinaceous nanostructures that, along with virus-like particles, encapsulins, nano-cages, and other macromolecular assemblies are being developed for potential biomedical applications. To facilitate such development, it would be valuable to characterize these nanostructures sub-cellular assembly and localization. However, traditional fluorescent protein fusions are not tolerated by GVs primary constituent protein, making optical microscopy a challenge. Here, we introduce a method for fluorescently visualizing intracellular GVs using the bioorthogonal label FlAsH, which becomes fluorescent upon binding the six-amino acid tetracysteine (TC) tag. We engineered the GV subunit protein, GvpA, to display the TC tag, and showed that GVs bearing TC-tagged GvpA can be successfully assembled and fluorescently visualized in HEK 293T cells. We used fluorescence images of the tagged GVs to study GV size and distance distributions within these cells. This bioorthogonal labeling approach will enable research to provide a greater understanding of GVs and could be adapted to similar proteinaceous nanostructures.
]]></description>
<dc:creator>Schrunk, E.</dc:creator>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Hurt, R. C.</dc:creator>
<dc:creator>Wu, D.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2023-12-01</dc:date>
<dc:identifier>doi:10.1101/2023.11.30.569486</dc:identifier>
<dc:title><![CDATA[Bioorthogonal labeling enables in situ fluorescence imaging of expressed gas vesicle nanostructures]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-12-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.12.06.570341v1?rss=1">
<title>
<![CDATA[
Rapid, concerted switching of the neural code in inferotemporal cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.12.06.570341v1?rss=1</link>
<description><![CDATA[
A fundamental paradigm in neuroscience is the concept of neural coding through tuning functions1. According to this idea, neurons encode stimuli through fixed mappings of stimulus features to firing rates. Here, we report that the tuning of visual neurons can rapidly and coherently change across a population to attend to a whole and its parts. We set out to investigate a longstanding debate concerning whether inferotemporal (IT) cortex uses a specialized code for representing specific types of objects or whether it uses a general code that applies to any object. We found that face cells in macaque IT cortex initially adopted a general code optimized for face detection. But following a rapid, concerted population event lasting < 20 ms, the neural code transformed into a face-specific one with two striking properties: (i) response gradients to principal detection-related dimensions reversed direction, and (ii) new tuning developed to multiple higher feature space dimensions supporting fine face discrimination. These dynamics were face specific and did not occur in response to objects. Overall, these results show that, for faces, face cells shift from detection to discrimination by switching from an object-general code to a face-specific code. More broadly, our results suggest a novel mechanism for neural representation: concerted, stimulus-dependent switching of the neural code used by a cortical area.
]]></description>
<dc:creator>Shi, Y.</dc:creator>
<dc:creator>Bi, D.</dc:creator>
<dc:creator>Hesse, J. K.</dc:creator>
<dc:creator>Lanfranchi, F. F.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Tsao, D. Y.</dc:creator>
<dc:date>2023-12-06</dc:date>
<dc:identifier>doi:10.1101/2023.12.06.570341</dc:identifier>
<dc:title><![CDATA[Rapid, concerted switching of the neural code in inferotemporal cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-12-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.12.06.570397v1?rss=1">
<title>
<![CDATA[
Machine-learning-based Structural Analysis of Interactions between Antibodies and Antigens 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.12.06.570397v1?rss=1</link>
<description><![CDATA[
Computational analysis of paratope-epitope interactions between antibodies and their corresponding antigens can facilitate our understanding of the molecular mechanism underlying humoral immunity and boost the design of new therapeutics for many diseases. The recent breakthrough in artificial intelligence has made it possible to predict protein-protein interactions and model their structures. Unfortunately, detecting antigen-binding sites associated with a specific antibody is still a challenging problem. To tackle this challenge, we implemented a deep learning model to characterize interaction patterns between antibodies and their corresponding antigens. With high accuracy, our model can distinguish between antibody-antigen complexes and other types of protein-protein complexes. More intriguingly, we can identify antigens from other common protein binding regions with an accuracy of higher than 70% even if we only have the epitope information. This indicates that antigens have distinct features on their surface that antibodies can recognize. Additionally, our model was unable to predict the partnerships between antibodies and their particular antigens. This result suggests that one antigen may be targeted by more than one antibody and that antibodies may bind to previously unidentified proteins. Taken together, our results support the precision of antibody-antigen interactions while also suggesting positive future progress in the prediction of specific pairing.
]]></description>
<dc:creator>Zhang, G.</dc:creator>
<dc:creator>Su, Z.</dc:creator>
<dc:creator>Zhang, T.</dc:creator>
<dc:creator>Wu, Y.</dc:creator>
<dc:date>2023-12-08</dc:date>
<dc:identifier>doi:10.1101/2023.12.06.570397</dc:identifier>
<dc:title><![CDATA[Machine-learning-based Structural Analysis of Interactions between Antibodies and Antigens]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-12-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2023.12.29.573592v1?rss=1">
<title>
<![CDATA[
Single tissue proteomics in Caenorhabditis elegans reveals proteins resident in intestinal lysosome-related organelles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2023.12.29.573592v1?rss=1</link>
<description><![CDATA[
The nematode intestine is the primary site for nutrient uptake and storage as well as the synthesis of biomolecules; lysosome-related organelles known as gut granules are important for many of these functions. Aspects of intestine biology are not well understood, including the export of the nutrients it imports and the molecules it synthesizes, as well as the complete functions and protein content of the gut granules. Here, we report a mass spectrometry-based proteomic analysis of the intestine of the Caenorhabditis elegans and of its gut granules. Overall, we identified approximately 5,000 proteins each in the intestine and the gonad and showed that most of these proteins can be detected in samples extracted from a single worm, suggesting the feasibility of individual-level genetic analysis using proteomes. Comparing proteomes and published transcriptomes of the intestine and the gonad, we identified proteins that appear to be synthesized in the intestine and then transferred to the gonad. To identify gut granule proteins, we compared the proteome of individual intestines deficient in gut granules to the wild-type. The identified gut granule proteome includes proteins known to be exclusively localized to the granules and additional putative novel gut granule proteins. We selected two of these putative gut granule proteins for validation via immunohistochemistry, and our successful confirmation of both suggests that our strategy was effective in identifying the gut granule proteome. Our results demonstrate the practicability of single tissue mass-spectrometry- based proteomic analysis in small organisms and in its utility for making discoveries.

Significance statementWe show that tissue-specific proteomic analysis is achievable and can be done efficiently at an individual level in a small nematode, with resolution sufficient for genetic analysis on a single animal basis. With data collected from single animals, we produced high-quality sets of proteins that described the proteomes of the gonad and the intestine. Comparison of these proteomes with the organs transcriptomes improved our understanding of interorgan protein transport. We applied single-tissue proteomic to describe the proteome of the gut granules in the nematode intestine, a specialized lysosome-related organelle with important functions but which is not well characterized, identifying proteins not previously known to be associated with LROs and verifying two by subcellular localization.
]]></description>
<dc:creator>Tan, C.-H.</dc:creator>
<dc:creator>Wang, T.-Y.</dc:creator>
<dc:creator>Park, H.</dc:creator>
<dc:creator>Lomenick, B.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2023-12-29</dc:date>
<dc:identifier>doi:10.1101/2023.12.29.573592</dc:identifier>
<dc:title><![CDATA[Single tissue proteomics in Caenorhabditis elegans reveals proteins resident in intestinal lysosome-related organelles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-12-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.01.05.574421v1?rss=1">
<title>
<![CDATA[
A Supervised Contrastive Framework for Learning Disentangled Representations of Cell Perturbation Data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.01.05.574421v1?rss=1</link>
<description><![CDATA[
CRISPR technology, combined with single-cell RNA-Seq, has opened the way to large scale pooled perturbation screens, allowing more systematic interrogations of gene functions in cells at scale. However, such Perturb-seq data poses many analysis challenges, due to its high-dimensionality, high level of technical noise, and variable Cas9 efficiency. The single-cell nature of the data also poses its own challenges, as we observe the heterogeneity of phenotypes in the unperturbed cells, along with the effect of the perturbations. All in all, these characteristics make it difficult to discern subtler effects. Existing tools, like mixscape and ContrastiveVI, provide partial solutions, but may oversimplify biological dynamics, or have low power to characterize perturbations with a smaller effect size. Here, we address these limitations by introducing the Supervised Contrastive Variational Autoencoder (SC-VAE). SC-VAE integrates guide RNA identity with gene expression data, ensuring a more discriminative analysis, and adopts the Hilbert-Schmidt Independence Criterion as a way to achieve disentangled representations, separating the heterogeneity in the control population from the effect of the perturbations. Evaluation on large-scale data sets highlights SC-VAEs superior sensitivity in identifying perturbation effects compared to ContrastiveVI, scVI and PCA. The perturbation embeddings better reflect known protein complexes (evaluated on CORUM), while its classifier offers promise in identifying assignment errors and cells escaping the perturbation phenotype. SC-VAE is readily applicable across diverse perturbation data sets.
]]></description>
<dc:creator>Tu, X.</dc:creator>
<dc:creator>Hutter, J.-C.</dc:creator>
<dc:creator>Wang, Z. J.</dc:creator>
<dc:creator>Kudo, T.</dc:creator>
<dc:creator>Regev, A.</dc:creator>
<dc:creator>Lopez, R.</dc:creator>
<dc:date>2024-01-08</dc:date>
<dc:identifier>doi:10.1101/2024.01.05.574421</dc:identifier>
<dc:title><![CDATA[A Supervised Contrastive Framework for Learning Disentangled Representations of Cell Perturbation Data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-01-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.01.07.574504v1?rss=1">
<title>
<![CDATA[
Data-driven system matrix manipulation enabling fast functional imaging and intra-image nonrigid motion correction in tomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.01.07.574504v1?rss=1</link>
<description><![CDATA[
Tomographic imaging modalities are described by large system matrices. Sparse sampling and tissue motion degrade system matrix and image quality. Various existing techniques improve the image quality without correcting the system matrices. Here, we compress the system matrices to improve computational efficiency (e.g., 42 times) using singular value decomposition and fast Fourier transform. Enabled by the efficiency, we propose (1) fast sparsely sampling functional imaging by incorporating a densely sampled prior image into the system matrix, which maintains the critical linearity while mitigating artifacts and (2) intra-image nonrigid motion correction by incorporating the motion as subdomain translations into the system matrix and reconstructing the translations together with the image iteratively. We demonstrate the methods in 3D photoacoustic computed tomography with significantly improved image qualities and clarify their applicability to X-ray CT and MRI or other types of imperfections due to the similarities in system matrices.
]]></description>
<dc:creator>Hu, P.</dc:creator>
<dc:creator>Tong, X.</dc:creator>
<dc:creator>Lin, L.</dc:creator>
<dc:creator>Wang, L.</dc:creator>
<dc:date>2024-01-08</dc:date>
<dc:identifier>doi:10.1101/2024.01.07.574504</dc:identifier>
<dc:title><![CDATA[Data-driven system matrix manipulation enabling fast functional imaging and intra-image nonrigid motion correction in tomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-01-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.01.17.576100v1?rss=1">
<title>
<![CDATA[
Integrative genomic analysis identifies unique immune environments associated with immunotherapy response in diffuse large B cell lymphoma 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.01.17.576100v1?rss=1</link>
<description><![CDATA[
Most diffuse large B-cell lymphoma (DLBCL) patients treated with bispecific antibodies (BsAb) or chimeric antigen receptor (CAR) T cells fail to achieve durable treatment responses, underscoring the need for a deeper understanding of mechanisms that regulate the immune environment and response to treatment. Here, an integrative, multi-omic approach was employed to characterize DLBCL immune environments, which effectively segregated DLBCLs into four quadrants - termed DLBCL-immune quadrants (IQ) - defined by cell-of-origin and immune-related gene set expression scores. Recurrent genomic alterations were enriched in each IQ, suggesting that lymphoma cell-intrinsic alterations contribute to orchestrating unique DLBCL immune environments. In relapsed/refractory DLBCL patients, DLBCL-IQ assignment correlated significantly with clinical benefit with the CD20 x CD3 BsAb, mosunetuzumab, but not with CD19-directed CAR T cells. DLBCL-IQ provides a new framework to conceptualize the DLBCL immune landscape and uncovers the differential impact of the endogenous immune environment on outcomes to BsAb and CAR T cell treatment.
]]></description>
<dc:creator>Tumuluru, S.</dc:creator>
<dc:creator>Godfrey, J. K.</dc:creator>
<dc:creator>Cooper, A.</dc:creator>
<dc:creator>Yu, J.</dc:creator>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>MacNabb, B. W.</dc:creator>
<dc:creator>Venkataraman, G.</dc:creator>
<dc:creator>Zha, Y.</dc:creator>
<dc:creator>Pelzer, B.</dc:creator>
<dc:creator>Song, J.</dc:creator>
<dc:creator>Duns, G.</dc:creator>
<dc:creator>Bolen, C.</dc:creator>
<dc:creator>Penuel, E.</dc:creator>
<dc:creator>Postovalova, E.</dc:creator>
<dc:creator>Kotlov, N.</dc:creator>
<dc:creator>Bagaev, A.</dc:creator>
<dc:creator>Fowler, N.</dc:creator>
<dc:creator>Smith, S. M.</dc:creator>
<dc:creator>Steidl, C.</dc:creator>
<dc:creator>Kline, J.</dc:creator>
<dc:date>2024-01-22</dc:date>
<dc:identifier>doi:10.1101/2024.01.17.576100</dc:identifier>
<dc:title><![CDATA[Integrative genomic analysis identifies unique immune environments associated with immunotherapy response in diffuse large B cell lymphoma]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-01-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.01.22.576704v1?rss=1">
<title>
<![CDATA[
Age-related memory CD8 T cells induce and track Alzheimers-like neurodegeneration 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.01.22.576704v1?rss=1</link>
<description><![CDATA[
Cerebral (A{beta}) plaque and (pTau) tangle deposition are hallmarks of Alzheimers disease (AD), yet are insufficient to confer complete AD-like neurodegeneration experimentally. Factors acting upstream of A{beta}/pTau in AD remain unknown, but their identification could enable earlier diagnosis and more effective treatments. T cell abnormalities are emerging AD hallmarks, and CD8 T cells were recently found to mediate neurodegeneration downstream of tangle deposition in hereditary neurodegeneration models. The precise impact of T cells downstream of A{beta}/fibrillar pTau, however, appears to vary depending on the animal model used. Our prior work suggested that antigen-specific memory CD8 T ("hiT") cells act upstream of A{beta}/pTau after brain injury. Here we examine whether hiT cells influence sporadic AD-like pathophysiology upstream of A{beta}/pTau. Examining neuropathology, gene expression, and behavior in our hiT mouse model we show that CD8 T cells induce plaque and tangle-like deposition, modulate AD-related genes, and ultimately result in progressive neurodegeneration with both gross and fine features of sporadic human AD. T cells required Perforin to initiate this pathophysiology, and IFN{gamma} for most gene expression changes and progression to more widespread neurodegenerative disease. Analogous antigen-specific memory CD8 T cells were significantly elevated in the brains of human AD patients, and their loss from blood corresponded to sporadic AD and related cognitive decline better than plasma pTau-217, a promising AD biomarker candidate. Our work is the first to identify an age-related factor acting upstream of A{beta}/pTau to initiate AD-like pathophysiology, the mechanisms promoting its pathogenicity, and its relevance to human sporadic AD.

Significance StatementThis study changes our view of Alzheimers Disease (AD) initiation and progression. Mutations promoting cerebral beta-amyloid (A{beta}) deposition guarantee rare genetic forms of AD. Thus, the prevailing hypothesis has been that A{beta} is central to initiation and progression of all AD, despite contrary animal and patient evidence. We show that age-related T cells generate neurodegeneration with compelling features of AD in mice, with distinct T cell functions required for pathological initiation and neurodegenerative progression. Knowledge from these mice was applied to successfully predict previously unknown features of human AD and generate novel tools for its clinical management.
]]></description>
<dc:creator>Panwar, A.</dc:creator>
<dc:creator>Rentsendorj, A.</dc:creator>
<dc:creator>Jhun, M.</dc:creator>
<dc:creator>Cohen, R. M.</dc:creator>
<dc:creator>Cordner, R.</dc:creator>
<dc:creator>Gull, N.</dc:creator>
<dc:creator>Pechnick, R. N.</dc:creator>
<dc:creator>Duvall, G.</dc:creator>
<dc:creator>Mardiros, A.</dc:creator>
<dc:creator>Golchian, D.</dc:creator>
<dc:creator>Schubloom, H.</dc:creator>
<dc:creator>Jin, L.-W.</dc:creator>
<dc:creator>Van Dam, D.</dc:creator>
<dc:creator>Vermeiren, Y.</dc:creator>
<dc:creator>De Reu, H.</dc:creator>
<dc:creator>De Deyn, P. P.</dc:creator>
<dc:creator>Raskatov, J. A.</dc:creator>
<dc:creator>Black, K. L.</dc:creator>
<dc:creator>Irvin, D. K.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>Wheeler, C. J.</dc:creator>
<dc:date>2024-01-22</dc:date>
<dc:identifier>doi:10.1101/2024.01.22.576704</dc:identifier>
<dc:title><![CDATA[Age-related memory CD8 T cells induce and track Alzheimers-like neurodegeneration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-01-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.02.15.580289v1?rss=1">
<title>
<![CDATA[
Adeno-Associated Viral Tools to Trace Neural Development and Connectivity Across Amphibians 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.02.15.580289v1?rss=1</link>
<description><![CDATA[
The development, evolution, and function of the vertebrate central nervous system (CNS) can be best studied using diverse model organisms. Amphibians, with their unique phylogenetic position at the transition between aquatic and terrestrial lifestyles, are valuable for understanding the origin and evolution of the tetrapod brain and spinal cord. Their metamorphic developmental transitions and unique regenerative abilities also facilitate the discovery of mechanisms for neural circuit remodeling and replacement. The genetic toolkit for amphibians, however, remains limited, with only a few species having sequenced genomes and a small number of transgenic lines available. In mammals, recombinant adeno-associated viral vectors (AAVs) have become a powerful alternative to genome modification for visualizing and perturbing the nervous system. AAVs are DNA viruses that enable neuronal transduction in both developing and adult animals with low toxicity and spatial, temporal, and cell-type specificity. However, AAVs have never been shown to transduce amphibian cells efficiently. To bridge this gap, we established a simple, scalable, and robust strategy to screen AAV serotypes in three distantly-related amphibian species: the frogs Xenopus laevis and Pelophylax bedriagae, and the salamander Pleurodeles waltl, in both developing larval tadpoles and post-metamorphic animals. For each species, we successfully identified at least two AAV serotypes capable of infecting the CNS; however, no pan-amphibian serotype was identified, indicating rapid evolution of AAV tropism. In addition, we developed an AAV-based strategy that targets isochronic cohorts of developing neurons - a critical tool for parsing neural circuit assembly. Finally, to enable visualization and manipulation of neural circuits, we identified AAV variants for retrograde tracing of neuronal projections in adult animals. Our findings expand the toolkit for amphibians to include AAVs, establish a generalizable workflow for AAV screening in non-canonical research organisms, generate testable hypotheses for the evolution of AAV tropism, and lay the foundation for modern cross-species comparisons of vertebrate CNS development, function, and evolution.
]]></description>
<dc:creator>Jaeger, E. C. B.</dc:creator>
<dc:creator>Vijatovic, D.</dc:creator>
<dc:creator>Deryckere, A.</dc:creator>
<dc:creator>Zorin, N.</dc:creator>
<dc:creator>Nguyen, A. L.</dc:creator>
<dc:creator>Ivanian, G.</dc:creator>
<dc:creator>Woych, J.</dc:creator>
<dc:creator>Arnold, R. C.</dc:creator>
<dc:creator>Ortega Gurrola, A.</dc:creator>
<dc:creator>Shvartsman, A.</dc:creator>
<dc:creator>Barbieri, F.</dc:creator>
<dc:creator>Toma, F. A.</dc:creator>
<dc:creator>Gorbsky, G. J.</dc:creator>
<dc:creator>Horb, M. E.</dc:creator>
<dc:creator>Cline, H. T.</dc:creator>
<dc:creator>Shay, T. F.</dc:creator>
<dc:creator>Kelley, D. B.</dc:creator>
<dc:creator>Yamaguchi, A.</dc:creator>
<dc:creator>Shein-Idelson, M.</dc:creator>
<dc:creator>Tosches, M. A.</dc:creator>
<dc:creator>Sweeney, L. B.</dc:creator>
<dc:date>2024-02-16</dc:date>
<dc:identifier>doi:10.1101/2024.02.15.580289</dc:identifier>
<dc:title><![CDATA[Adeno-Associated Viral Tools to Trace Neural Development and Connectivity Across Amphibians]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-02-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.03.583239v1?rss=1">
<title>
<![CDATA[
Unethical amnesia brain: Memory and metacognitive distortion induced by dishonesty 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.03.583239v1?rss=1</link>
<description><![CDATA[
Unethical actions and decisions may distort human memory in two aspects: memory accuracy and metacognition. However, the neural and computational mechanisms underlying the metacognition distortion caused by repeated dishonesty remain largely unknown. Here, we performed two fMRI studies, including one replication study, with an information-sending task in the scanner. The main moral decision task in the scanner involves consistency and reward as two main factors, combined with a pre-scan and post-scan memory test together with mouse tracking. With multiple dimensions of metrics to measure metacognition, we test whether the inter-subject metacognition change correlates with how participants trade off consistency and reward. We find that the compression of representational geometry of reward in the orbitofrontal cortex (OFC) is correlated with both immediate and delayed metacognition changes. Also, the functional connectivity between the dorsolateral prefrontal cortex (DLPFC) and the left temporoparietal junction (lTPJ) under dishonest responses can predict both immediate and delayed metacognition changes in memory. These results suggest that decision-making, emotion, and memory-related brain regions together play a key role in metacognition change after immoral action, shedding light on the neural mechanism of the complex interplay between moral decisions, cognitive processes, and memory distortion.

 I did that, says my memory.

 I could not have done that, says my pride, and remains inexorable.

Eventually - the memory yields.

--Nietzsche[1]
]]></description>
<dc:creator>Xu, X. J.</dc:creator>
<dc:creator>Mobbs, D.</dc:creator>
<dc:creator>Wu, H.</dc:creator>
<dc:date>2024-03-06</dc:date>
<dc:identifier>doi:10.1101/2024.03.03.583239</dc:identifier>
<dc:title><![CDATA[Unethical amnesia brain: Memory and metacognitive distortion induced by dishonesty]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.08.584120v1?rss=1">
<title>
<![CDATA[
Variant mutation in SARS-CoV-2 nucleocapsid enhances viral infection via altered genomic encapsidation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.08.584120v1?rss=1</link>
<description><![CDATA[
The evolution of SARS-CoV-2 variants and their respective phenotypes represents an important set of tools to understand basic coronavirus biology as well as the public health implications of individual mutations in variants of concern. While mutations outside of Spike are not well studied, the entire viral genome is undergoing evolutionary selection, particularly the central disordered linker region of the nucleocapsid (N) protein. Here, we identify a mutation (G215C), characteristic of the Delta variant, that introduces a novel cysteine into this linker domain, which results in the formation of a disulfide bond and a stable N-N dimer. Using reverse genetics, we determined that this cysteine residue is necessary and sufficient for stable dimer formation in a WA1 SARS-CoV-2 background, where it results in significantly increased viral growth both in vitro and in vivo. Finally, we demonstrate that the N:G215C virus packages more nucleocapsid per virion and that individual virions are larger, with elongated morphologies.
]]></description>
<dc:creator>Kubinski, H. C.</dc:creator>
<dc:creator>Despres, H. W.</dc:creator>
<dc:creator>Johnson, B. A.</dc:creator>
<dc:creator>Schmidt, M. M.</dc:creator>
<dc:creator>Jaffrani, S. A.</dc:creator>
<dc:creator>Mills, M. G.</dc:creator>
<dc:creator>Lokugamage, K.</dc:creator>
<dc:creator>Dumas, C. M.</dc:creator>
<dc:creator>Shirley, D. J.</dc:creator>
<dc:creator>Estes, L. K.</dc:creator>
<dc:creator>Pekosz, A.</dc:creator>
<dc:creator>Crothers, J. W.</dc:creator>
<dc:creator>Roychoudhury, P.</dc:creator>
<dc:creator>Greninger, A. L.</dc:creator>
<dc:creator>Jerome, K. R.</dc:creator>
<dc:creator>Martorelli Di Genova, B.</dc:creator>
<dc:creator>Walker, D. H.</dc:creator>
<dc:creator>Ballif, B. A.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Menachery, V. D.</dc:creator>
<dc:creator>Bruce, E. A.</dc:creator>
<dc:date>2024-03-11</dc:date>
<dc:identifier>doi:10.1101/2024.03.08.584120</dc:identifier>
<dc:title><![CDATA[Variant mutation in SARS-CoV-2 nucleocapsid enhances viral infection via altered genomic encapsidation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.11.584528v1?rss=1">
<title>
<![CDATA[
Non-invasive laser speckle imaging of extra-embryonic blood vessels in intact few-days-old avian eggs 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.11.584528v1?rss=1</link>
<description><![CDATA[
Imaging blood vessels in early-stage avian embryos has a wide range of practical applications for developmental biology studies, drug and vaccine testing, and early sex determination. Optical imaging such as brightfield transmission imaging offers a compelling solution due to its safe non-ionizing radiation, and operational benefits. However, it comes with challenges such as eggshell opacity and light scattering. To address these, we have revisited an approach based on laser speckle contrast imaging (LSCI) and demonstrated a high quality, comprehensive and non-invasive visualization of blood vessels in few-days-old chicken eggs, with blood vessel as small as 100 {micro}m in diameter (with LSCI profile full-width-at-half-maximum of 275 {micro}m). We present its non-invasive use for monitoring blood flow, measuring the embryos heartbeat, and determining the embryos developmental stages using machine learning with 85% accuracy from stage HH15 to HH22. This method can potentially be used for non-invasive longitudinal studies of cardiovascular development and angiogenesis, as well as egg screening for the poultry industry.
]]></description>
<dc:creator>Dong, Z.</dc:creator>
<dc:creator>Mahler, S.</dc:creator>
<dc:creator>Readhead, C.</dc:creator>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>Dickson, M.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>Yang, C.</dc:creator>
<dc:date>2024-03-14</dc:date>
<dc:identifier>doi:10.1101/2024.03.11.584528</dc:identifier>
<dc:title><![CDATA[Non-invasive laser speckle imaging of extra-embryonic blood vessels in intact few-days-old avian eggs]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.12.583048v1?rss=1">
<title>
<![CDATA[
miRNA circuit modules for precise, tunable control of gene expression 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.12.583048v1?rss=1</link>
<description><![CDATA[
Accurate control of transgene expression is important for research and therapy but challenging to achieve in most settings. miRNA-based regulatory circuits can be incorporated within transgenes for improved control. However, the design principles, performance limits, and applications of these circuits in research and biotechnology have not been systematically determined. Here, combining modeling and experiments, we introduce miRNA-based circuit modules, termed DIMMERs, that establish precise, tunable control of transgene expression across diverse cell types to facilitate imaging, editing, and gene therapy. The circuits use multivalent miRNA regulatory interactions to achieve nearly uniform, tunable, protein expression over two orders of magnitude variation in gene dosage. They function across diverse cell types, and can be multiplexed for independent regulation of multiple genes. DIMMERs reduce off-target CRISPR base editing, improve single-molecule imaging, and allow live tracking of AAV-delivered transgene expression in mouse cortical neurons. DIMMERs thus enable accurate regulation for research and biotechnology applications.
]]></description>
<dc:creator>Du, R.</dc:creator>
<dc:creator>Flynn, M. J.</dc:creator>
<dc:creator>Honsa, M.</dc:creator>
<dc:creator>Jungmann, R.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:date>2024-03-12</dc:date>
<dc:identifier>doi:10.1101/2024.03.12.583048</dc:identifier>
<dc:title><![CDATA[miRNA circuit modules for precise, tunable control of gene expression]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.13.584179v1?rss=1">
<title>
<![CDATA[
Synthetic dosage-compensating miRNA circuits for quantitative gene therapy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.13.584179v1?rss=1</link>
<description><![CDATA[
A longstanding challenge in gene therapy is expressing a dosage-sensitive gene within a tight therapeutic window. For example, loss of MECP2 function causes Rett syndrome, while its duplication causes MECP2 duplication syndrome. Viral gene delivery methods generate variable numbers of gene copies in individual cells, creating a need for gene dosage-invariant expression systems. Here, we introduce a compact miRNA-based, incoherent feed-forward loop circuit that achieves precise control of Mecp2 expression in cells and brains, and improves outcomes in an AAV-based mouse model of Rett syndrome gene therapy. Single molecule analysis of endogenous and ectopic Mecp2 mRNA revealed precise, sustained expression across a broad range of gene dosages. Delivered systemically in a brain-targeting AAV capsid, the circuit strongly suppressed Rett behavioral symptoms for over 24 weeks, outperforming an unregulated gene therapy. These results demonstrate that synthetic miRNA-based regulatory circuits can enable precise in vivo expression to improve the safety and efficacy of gene therapy.

One sentence description: A synthetic miRNA-based incoherent feed-forward loop circuit embedded in a gene delivery vector overcomes the challenge of overexpression toxicity in a mouse model of Rett syndrome gene therapy.
]]></description>
<dc:creator>Flynn, M. J.</dc:creator>
<dc:creator>Mayfield, A. M.</dc:creator>
<dc:creator>Du, R.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:date>2024-03-14</dc:date>
<dc:identifier>doi:10.1101/2024.03.13.584179</dc:identifier>
<dc:title><![CDATA[Synthetic dosage-compensating miRNA circuits for quantitative gene therapy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.14.584939v1?rss=1">
<title>
<![CDATA[
Amyloid Beta Oligomers Accelerate ATP-Dependent Phase Separation of Ago2 to RNA Processing Bodies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.14.584939v1?rss=1</link>
<description><![CDATA[
Phase separation to insoluble membrane-less organelles is a major way of activity regulation of specific proteins in eukaryotic cells. miRNA-repressed mRNAs and Ago proteins are known to be localized to RNA-processing bodies, the subcellular structures which are formed due to assembly of several RNA binding and regulatory proteins in eukaryotic cells. Ago2 is the most important miRNA binding protein that by forming complex with miRNA binds to mRNAs having cognate miRNA binding sites and represses protein synthesis in mammalian cells. Factors which control compartmentalization of Ago2 and miRNA-repressed mRNAs to RNA processing bodies are largely unknown. We have adopted a detergent permeabilized cell-based assay system to follow the phase separation of exogenously added Ago2 to RNA processing bodies in vitro. The Ago2 phase separation process is ATP dependent and is influenced by osmolarity and salt concentration of the reaction buffer. miRNA binding of Ago2 is essential for its targeting to RNA processing bodies and the compartmentalization process gets retarded by miRNA binding "sponge" protein HuR. This assay system found to be useful in identification of amyloid beta oligomers as miRNA-activity modulators which repress miRNA activity by enhancing Ago2-miRNP targeting to RNA processing bodies.

Graphical Abstract

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=126 SRC="FIGDIR/small/584939v1_ufig1.gif" ALT="Figure 1">
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org.highwire.dtl.DTLVardef@1fe06eeorg.highwire.dtl.DTLVardef@7904b1org.highwire.dtl.DTLVardef@1231746org.highwire.dtl.DTLVardef@cd1405_HPS_FORMAT_FIGEXP  M_FIG C_FIG O_LImiRNA bound Ago2 gets phase separated in vitro to RNA processing bodies (PBs) in detergent permeabilized mammalian cells.
C_LIO_LIPhase separation of Ago2 to PBs is controlled by presence of ATP and RNA.
C_LIO_LIAmyloid beta oligomers retard dynamics of Ago2 bodies to inhibit miRNA function and enhance PB targeting of Ago2 miRNPs.
C_LIO_LImicroRNA binding protein HuR can rescue Ago2 miRNP from PBs and inverse the effect of amyloid beta oligomers.
C_LI
]]></description>
<dc:creator>Ray, S.</dc:creator>
<dc:creator>Roychowdhury, S.</dc:creator>
<dc:creator>Chakraborty, Y.</dc:creator>
<dc:creator>Banerjee, S.</dc:creator>
<dc:creator>Chattopadhyay, K.</dc:creator>
<dc:creator>Mukherjee, K.</dc:creator>
<dc:creator>Bhattacharyya, S. N.</dc:creator>
<dc:date>2024-03-14</dc:date>
<dc:identifier>doi:10.1101/2024.03.14.584939</dc:identifier>
<dc:title><![CDATA[Amyloid Beta Oligomers Accelerate ATP-Dependent Phase Separation of Ago2 to RNA Processing Bodies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.14.585127v1?rss=1">
<title>
<![CDATA[
Thoracic epidural blockade after myocardial infarction benefits from anti-arrhythmic pathways mediated in part by parasympathetic modulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.14.585127v1?rss=1</link>
<description><![CDATA[
BackgroundThoracic epidural anesthesia (TEA) has been shown to reduce the burden of ventricular tachyarrhythmias (VT) in small case-series of patients with refractory VT and cardiomyopathy. However, its electrophysiological and autonomic effects in diseased hearts remain unclear and its use after myocardial infarction (MI) is limited by concerns for potential RV dysfunction.

MethodsMI was created in Yorkshire pigs (N=22) by LAD occlusion. Six weeks post-MI, an epidural catheter was placed at the C7-T1 vertebral level for injection of 2% lidocaine. RV and LV hemodynamics were recorded using Millar pressure-conductance catheters, and ventricular activation-recovery intervals (ARIs), a surrogate of action potential durations, by a 56-electrode sock and 64-electrode basket catheter. Hemodynamics and ARIs, baroreflex sensitivity (BRS) and intrinsic cardiac neural activity, and ventricular effective refractory periods (ERP) and slope of restitution (Smax) were assessed before and after TEA. VT/VF inducibility was assessed by programmed electrical stimulation.

ResultsTEA reduced inducibility of VT/VF by 70%. TEA did not affect RV-systolic pressure or contractility, although LV-systolic pressure and contractility decreased modestly. Global and regional ventricular ARIs increased, including in scar and border zone regions post-TEA. TEA reduced ARI dispersion specifically in border zone regions. Ventricular ERPs prolonged significantly at critical sites of arrhythmogenesis, and Smax was reduced. Interestingly, TEA significantly improved cardiac vagal function, as measured by both BRS and intrinsic cardiac neural activity.

ConclusionTEA does not compromise RV function in infarcted hearts. Its anti-arrhythmic mechanisms are mediated by increases in ventricular ERP and ARIs, decreases in Smax, and reductions in border zone heterogeneity. TEA improves parasympathetic function, which may independently underlie some of its observed anti-arrhythmic mechanisms. This study provides novel insights into the anti-arrhythmic mechanisms of TEA, while highlighting its applicability to the clinical setting.

Abstract IllustrationMyocardial infarction is known to cause cardiac autonomic dysfunction characterized by sympathoexcitation coupled with reduced vagal tone. This pathological remodeling collectively predisposes to ventricular arrhythmia. Thoracic epidural anesthesia not only blocks central efferent sympathetic outflow, but by also blocking ascending projections of sympathetic afferents, relieving central inhibition of vagal function. These complementary autonomic effects of thoracic epidural anesthesia may thus restore autonomic balance, thereby improving ventricular electrical stability and suppressing arrhythmogenesis. DRG=dorsal root ganglion, SG=stellate ganglion.



O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=117 SRC="FIGDIR/small/585127v1_ufig1.gif" ALT="Figure 1">
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org.highwire.dtl.DTLVardef@1150b29org.highwire.dtl.DTLVardef@8fd741org.highwire.dtl.DTLVardef@17d16bforg.highwire.dtl.DTLVardef@1608799_HPS_FORMAT_FIGEXP  M_FIG C_FIG
]]></description>
<dc:creator>Hoang, J. D.</dc:creator>
<dc:creator>Van Weperen, V. Y.</dc:creator>
<dc:creator>Kang, K.-W.</dc:creator>
<dc:creator>Jani, N.</dc:creator>
<dc:creator>Swid, M. A.</dc:creator>
<dc:creator>Chan, C. A.</dc:creator>
<dc:creator>Lokhandwala, Z. A.</dc:creator>
<dc:creator>Lux, R. L.</dc:creator>
<dc:creator>Vaseghi, M.</dc:creator>
<dc:date>2024-03-16</dc:date>
<dc:identifier>doi:10.1101/2024.03.14.585127</dc:identifier>
<dc:title><![CDATA[Thoracic epidural blockade after myocardial infarction benefits from anti-arrhythmic pathways mediated in part by parasympathetic modulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.15.584894v1?rss=1">
<title>
<![CDATA[
Correspondence of fentanyl brain pharmacokinetics and behavior measured via engineering opioids biosensors and computational ethology 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.15.584894v1?rss=1</link>
<description><![CDATA[
Despite the ongoing epidemic of opioid use disorder and death by fentanyl overdose, opioids remain the gold standard for analgesics. Pharmacokinetics (PK) dictates the individuals experience and utility of drugs; however, PK and behavioral outcomes have been conventionally studied in separate groups, even in preclinical models. To bridge this gap, we developed the first class of sensitive, selective, and genetically encodable fluorescent opioid biosensors, iOpioidSnFRs, including the fentanyl sensor, iFentanylSnFR. We expressed iFentanylSnFR in the ventral tegmental area of mice and recorded [fentanyl] alongside videos of behaviors before and after administration. We developed a machine vision routine to quantify the effects of the behavior on locomotor activity. We found that mice receiving fentanyl exhibited a repetitive locomotor pattern that paralleled the [fentanyl] time course. In a separate experiment, mice navigating a complex maze for water showed a dose-dependent impairment in navigation, in which animals repeated incorrect paths to the exclusion of most of the unexplored maze for the duration of the average fentanyl time course. This approach complements classical operant conditioning experiments and introduces a key feature of human addiction, the ability to carry out an ethologically relevant survival task, only now quantified in rodents. Finally, we demonstrate the utility of iFentanylSnFR in detecting fentanyl spiked into human biofluids and the generalizability of engineering methods to evolve selective biosensors of other opioids, such as tapentadol and levorphanol. These results encourage diagnostic and continuous monitoring approaches to personalizing opioid regimens for humans.
]]></description>
<dc:creator>Muthusamy, A. K.</dc:creator>
<dc:creator>Rosenberg, M.</dc:creator>
<dc:creator>Kim, C. H.</dc:creator>
<dc:creator>Wang, A. Z.</dc:creator>
<dc:creator>Ebisu, H.</dc:creator>
<dc:creator>Chin, T. M.</dc:creator>
<dc:creator>Koranne, A.</dc:creator>
<dc:creator>Marvin, J. S.</dc:creator>
<dc:creator>Cohen, B. N.</dc:creator>
<dc:creator>Looger, L. L.</dc:creator>
<dc:creator>Oka, Y.</dc:creator>
<dc:creator>Meister, M.</dc:creator>
<dc:creator>Lester, H. A.</dc:creator>
<dc:date>2024-03-16</dc:date>
<dc:identifier>doi:10.1101/2024.03.15.584894</dc:identifier>
<dc:title><![CDATA[Correspondence of fentanyl brain pharmacokinetics and behavior measured via engineering opioids biosensors and computational ethology]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.15.585317v1?rss=1">
<title>
<![CDATA[
Impact of Chemical Dynamics of Commercial PURE Systems on Malachite Green Aptamer Fluorescence 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.15.585317v1?rss=1</link>
<description><![CDATA[
The malachite green aptamer (MGapt) is known for its utility in RNA measurement in vivo and lysate-based cell-free protein systems. However, MGapt fluorescence dynamics do not accurately reflect mRNA concentration. Our study finds that MGapt fluorescence is unstable in commercial PURE systems. We discovered that the chemical composition of the cell-free reaction strongly influences MGapt fluorescence, which leads to inaccurate RNA calculations. Specific to the commercial system, we posit that MGapt fluorescence is significantly affected by the systems chemical properties, governed notably by the presence of dithiothreitol (DTT). We propose a model that, on average, accurately predicts MGapt measurement within a 10% margin, leveraging DTT concentration as a critical factor. This model sheds light on the complex dynamics of MGapt in cell-free systems and underscores the importance of considering environmental factors in RNA measurements using aptamers.
]]></description>
<dc:creator>Jurado, Z.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2024-03-16</dc:date>
<dc:identifier>doi:10.1101/2024.03.15.585317</dc:identifier>
<dc:title><![CDATA[Impact of Chemical Dynamics of Commercial PURE Systems on Malachite Green Aptamer Fluorescence]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.18.585647v1?rss=1">
<title>
<![CDATA[
Allele Sails: launching traits and fates into wild populations with DNA sequence modifiers 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.18.585647v1?rss=1</link>
<description><![CDATA[
Population-scale genome editing can be used to alter the composition or fate of wild populations. One approach to achieving these aims utilizes a synthetic gene drive element--a multi-gene cassette--to bring about an increase in the frequency of an existing allele. However, the use of gene drives is complicated by the multiple scientific, regulatory, and social issues associated with transgene persistence and gene flow. Alternatives in which transgenes are not driven could potentially avoid some of these issues. Here we propose an approach to population scale gene editing using a system we refer to as an Allele Sail. An Allele Sail consists of a genome editor (the Wind) that introduces DNA sequence edits (the Sail) at one or more sites, resulting in progeny that are viable and fertile. The editor, such as a sequence-specific nuclease, or a prime- or base-editor, is inherited in a Mendelian fashion. Meanwhile, the edits it creates experience an arithmetic, Super-Mendelian increase in frequency. We explore this system using agent-based modeling, and identify contexts in which a single, low frequency release of an editor brings edits to a very high frequency. We also identify conditions in which manipulation of sex determination can be used to bring about population suppression. Current regulatory frameworks often distinguish between transgenics as genetically modified organisms (GMOs), and their edited non-transgenic progeny as non-GMO. In this context an Allele Sail provides a path to alter traits and fates of wild populations in ways that may be considered more acceptable.
]]></description>
<dc:creator>Johnson, M. L.</dc:creator>
<dc:creator>Hay, B.</dc:creator>
<dc:creator>Maselko, M.</dc:creator>
<dc:date>2024-03-19</dc:date>
<dc:identifier>doi:10.1101/2024.03.18.585647</dc:identifier>
<dc:title><![CDATA[Allele Sails: launching traits and fates into wild populations with DNA sequence modifiers]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.20.586022v1?rss=1">
<title>
<![CDATA[
Sensory integration of food availability and population density during the diapause exit decision involves insulin-like signaling in  Caenorhabditis elegans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.20.586022v1?rss=1</link>
<description><![CDATA[
Decisions made over long time scales, such as life cycle decisions, require coordinated interplay between sensory perception and sustained gene expression. The Caenorhabditis elegans dauer (or diapause) exit developmental decision requires sensory integration of population density and food availability to induce an all-or-nothing organismal-wide response, but the mechanism by which this occurs remains unknown. Here, we demonstrate how the ASJ chemosensory neurons, known to be critical for dauer exit, perform sensory integration at both the levels of gene expression and calcium activity. In response to favorable conditions, dauers rapidly produce and secrete the dauer exit-promoting insulin-like peptide INS-6. Expression of ins-6 in the ASJ neurons integrate population density and food level and can reflect decision commitment since dauers committed to exiting have higher ins-6 expression levels than those of non-committed dauers. Calcium imaging in dauers reveals that the ASJ neurons are activated by food, and this activity is suppressed by pheromone, indicating that sensory integration also occurs at the level of calcium transients. We find that ins-6 expression in the ASJ neurons depends on neuronal activity in the ASJs, cGMP signaling, a CaM-kinase pathway, and the pheromone components ascr#8 and ascr#2. We propose a model in which decision commitment to exit the dauer state involves an autoregulatory feedback loop in the ASJ neurons that promotes high INS-6 production and secretion. These results collectively demonstrate how insulin-like peptide signaling helps animals compute long-term decisions by bridging sensory perception to decision execution.

Summary/Significance StatementAnimals must respond appropriately to multiple sensory stimuli to make informed decisions. It remains unclear how the nervous system is able to integrate different sensory cues and propagate that information towards making decisions over longer timescales. We use the nematode Caenorhabditis elegans to investigate how sensory integration occurs during the decision to exit diapause, a stress-resistant developmentally arrested state triggered by multiple sensory inputs including food availability and population density. We show how expression of an insulin-like peptide critical to dauer exit reflects the sensory integration process and decision commitment, and we dissect the regulation of this insulin-like peptides expression. Our study explicitly analyzes the relationship between neuronal activity and neuropeptide expression during a complex decision with diverse sensory inputs.
]]></description>
<dc:creator>Zhang, M. G.</dc:creator>
<dc:creator>Seyedolmohadesin, M.</dc:creator>
<dc:creator>Mercado, S. H.</dc:creator>
<dc:creator>Park, H.</dc:creator>
<dc:creator>Finnen, N.</dc:creator>
<dc:creator>Schroeder, F. C.</dc:creator>
<dc:creator>Venkatachalam, V.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2024-03-25</dc:date>
<dc:identifier>doi:10.1101/2024.03.20.586022</dc:identifier>
<dc:title><![CDATA[Sensory integration of food availability and population density during the diapause exit decision involves insulin-like signaling in  Caenorhabditis elegans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.23.586412v1?rss=1">
<title>
<![CDATA[
A human commons cell atlas reveals cell type specificity for OAS1 isoforms 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.23.586412v1?rss=1</link>
<description><![CDATA[
We describe an open source Human Commons Cell Atlas comprising 2.9 million cells across 27 tissues that can be easily updated and that is structured to facilitate custom analyses. To showcase the flexibility of the atlas, we demonstrate that it can be used to study isoforms of genes at cell resolution. In particular, we study cell type specificity of isoforms of OAS1, which has been shown to offer SARS-CoV-2 protection in certain individuals that display higher expression of the p46 isoform. Using our commons cell atlas we localize the OAS1 p44b isoform to the testis, and find that it is specific to round and elongating spermatids. By virtue of enabling customized analyses via a modular and dynamic atlas structure, the commons cell atlas should be useful for exploratory analyses that are intractable within the rigid framework of current gene-centric cell atlases.
]]></description>
<dc:creator>Galvez-Merchan, A.</dc:creator>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2024-03-24</dc:date>
<dc:identifier>doi:10.1101/2024.03.23.586412</dc:identifier>
<dc:title><![CDATA[A human commons cell atlas reveals cell type specificity for OAS1 isoforms]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.23.586413v1?rss=1">
<title>
<![CDATA[
Algorithms for a Commons Cell Atlas 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.23.586413v1?rss=1</link>
<description><![CDATA[
Cell atlas projects curate representative datasets, cell types, and marker genes for tissues across an organism. Despite their ubiquity, atlas projects rely on duplicated and manual effort to curate marker genes and annotate cell types. The size of atlases coupled with a lack of data-compatible tools make reprocessing and analysis of their data near-impossible. To overcome these challenges, we present a collection of data, algorithms, and tools to automate cataloging and analyzing cell types across tissues in an organism, and demonstrate its utility in building a human atlas.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Galvez-Merchan, A.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2024-03-26</dc:date>
<dc:identifier>doi:10.1101/2024.03.23.586413</dc:identifier>
<dc:title><![CDATA[Algorithms for a Commons Cell Atlas]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.23.586416v1?rss=1">
<title>
<![CDATA[
Kilohertz volumetric imaging of in-vivo dynamics using squeezed light field microscopy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.23.586416v1?rss=1</link>
<description><![CDATA[
Volumetric functional imaging of transient cellular signaling and motion dynamics poses a significant challenge to current microscopy techniques, primarily due to limitations in hardware bandwidth and the restricted photon budget within short exposure times. In response to this challenge, we present squeezed light field microscopy (SLIM), a computational imaging method that enables rapid detection of high-resolution three-dimensional (3D) light signals using only a single, low-format camera sensor area. SLIM pushes the boundaries of 3D optical microscopy, achieving over one thousand volumes per second across a large field of view of 550 m in diameter and 300 m in depth with a spatial resolution of 3.6 m laterally and 6 m axially. Using SLIM, we demonstrated blood cell velocimetry across the embryonic zebrafish brain and in a free-moving tail exhibiting high-frequency swinging motion. The millisecond temporal resolution also enables accurate voltage imaging of neural membrane potentials in the leech ganglion, and in the hippocampus of behaving mice. These results collectively establish SLIM as a versatile and robust imaging tool for high-speed microscopy applications.
]]></description>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>Zhao, R.</dc:creator>
<dc:creator>Wagenaar, D. A.</dc:creator>
<dc:creator>Kang, W.</dc:creator>
<dc:creator>Lee, C.</dc:creator>
<dc:creator>Schmidt, W.</dc:creator>
<dc:creator>Pammar, A.</dc:creator>
<dc:creator>Zhu, E.</dc:creator>
<dc:creator>Wong, G. C. L.</dc:creator>
<dc:creator>Liang, R.</dc:creator>
<dc:creator>Hsiai, T.</dc:creator>
<dc:creator>Gao, L.</dc:creator>
<dc:date>2024-03-27</dc:date>
<dc:identifier>doi:10.1101/2024.03.23.586416</dc:identifier>
<dc:title><![CDATA[Kilohertz volumetric imaging of in-vivo dynamics using squeezed light field microscopy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.25.586385v1?rss=1">
<title>
<![CDATA[
Nonadjacent Dependencies and Syntactic Structure of Chimpanzee Action During a Natural Tool-Use Task 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.25.586385v1?rss=1</link>
<description><![CDATA[
The hierarchical organization of sequential behaviour, and the ability to compensate for nonadjacent sequential dependencies, are fundamental and interrelated abilities supporting complex human behaviours, including language and tool use. To understand how the cognition underlying these structural properties of human behaviour evolved, we can gain valuable insight from studying the sequential behaviours of nonhuman animals. Among the behaviours of nonhuman apes, tool use has been hypothesised to be a domain of behaviour which likely involves hierarchical organization. However thus far, evidence supporting this hypothesis comes from methodologies which have been criticised in their objectivity. Additionally, the extent to which nonadjacent dependencies appear in primate action sequences during tool use has not been formally investigated. We used estimations of mutual information (MI) - a measure of dependency strength between sequence elements - to evaluate both the extent to which wild chimpanzees produce nonadjacent dependencies during a naturalistic tool-use task (nut cracking), as well as how sequences of actions are organized during tool use. Half of adult chimpanzees produce nonadjacent dependencies at significantly greater sequential distances than comparable, nonhierarchical Markov models, including when repeated actions had been accounted for. Additionally, for the majority of chimpanzees, MI decay with increasing sequential distance included a power-law relationship, which is a key indicator that most chimpanzees draw upon forms of hierarchical structuring when organizing behaviours during tool use. Our analysis offered the greatest support for a system of organization which involved the production of short subroutines of actions (2-8 actions), which are hierarchically arranged into sequences - a finding which is consistent with previous qualitative descriptions of ape tool-use behaviours. Interindividual variability was detected within our analysis in both the distance dependencies were detected, and the most likely structuring mechanism for sequential action organization. We discuss these results in light of possible interindividual variation, in addition to methodological considerations for applications of MI estimations to sequential behaviours. Moreover, we discuss our main findings alongside hypotheses for the coevolution of complex syntax in language and tool-action across hominin evolutionary history.
]]></description>
<dc:creator>Howard-Spink, E.</dc:creator>
<dc:creator>Hayashi, M.</dc:creator>
<dc:creator>Matsuzawa, T.</dc:creator>
<dc:creator>Schofield, D.</dc:creator>
<dc:creator>Gruber, T.</dc:creator>
<dc:creator>Biro, D.</dc:creator>
<dc:date>2024-03-29</dc:date>
<dc:identifier>doi:10.1101/2024.03.25.586385</dc:identifier>
<dc:title><![CDATA[Nonadjacent Dependencies and Syntactic Structure of Chimpanzee Action During a Natural Tool-Use Task]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-03-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.03.30.587094v1?rss=1">
<title>
<![CDATA[
Directed Evolution of Acoustic Reporter Genes Using High-Throughput Acoustic Screening 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.03.30.587094v1?rss=1</link>
<description><![CDATA[
A major challenge in the fields of biological imaging and synthetic biology is noninvasively visualizing the functions of natural and engineered cells inside opaque samples such as living animals. One promising technology that addresses this limitation is ultrasound (US), with its penetration depth of several cm and spatial resolution on the order of 100 {micro}m.1 Within the past decade, reporter genes for US have been introduced2,3 and engineered4,5 to link cellular functions to US signals via heterologous expression in commensal bacteria and mammalian cells. These acoustic reporter genes (ARGs) represent a novel class of genetically encoded US contrast agent, and are based on air-filled protein nanostructures called gas vesicles (GVs).6 Just as the discovery of fluorescent proteins was followed by the improvement and diversification of their optical properties through directed evolution, here we describe the evolution of GVs as acoustic reporters. To accomplish this task, we establish high-throughput, semi-automated acoustic screening of ARGs in bacterial cultures and use it to screen mutant libraries for variants with increased nonlinear US scattering. Starting with scanning site saturation libraries for two homologs of the primary GV structural protein, GvpA/B, two rounds of evolution resulted in GV variants with 5- and 14-fold stronger acoustic signals than the parent proteins. We anticipate that this and similar approaches will help high-throughput protein engineering play as large a role in the development of acoustic biomolecules as it has for their fluorescent counterparts.
]]></description>
<dc:creator>Hurt, R. C.</dc:creator>
<dc:creator>Jin, Z.</dc:creator>
<dc:creator>Soufi, M.</dc:creator>
<dc:creator>Wong, K. K.</dc:creator>
<dc:creator>Sawyer, D. P.</dc:creator>
<dc:creator>Shen, H. K.</dc:creator>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Deshpande, R.</dc:creator>
<dc:creator>Zhang, R.</dc:creator>
<dc:creator>Mittelstein, D. R.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2024-04-01</dc:date>
<dc:identifier>doi:10.1101/2024.03.30.587094</dc:identifier>
<dc:title><![CDATA[Directed Evolution of Acoustic Reporter Genes Using High-Throughput Acoustic Screening]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-04-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.04.04.588111v1?rss=1">
<title>
<![CDATA[
The impact of package selection and versioning on single-cell RNA-seq analysis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.04.04.588111v1?rss=1</link>
<description><![CDATA[
Standard single-cell RNA-sequencing analysis (scRNA-seq) workflows consist of converting raw read data into cell-gene count matrices through sequence alignment, followed by analyses including filtering, highly variable gene selection, dimensionality reduction, clustering, and differential expression analysis. Seurat and Scanpy are the most widely-used packages implementing such workflows, and are generally thought to implement individual steps similarly. We investigate in detail the algorithms and methods underlying Seurat and Scanpy and find that there are, in fact, considerable differences in the outputs of Seurat and Scanpy. The extent of differences between the programs is approximately equivalent to the variability that would be introduced in benchmarking scRNA-seq datasets by sequencing less than 5% of the reads or analyzing less than 20% of the cell population. Additionally, distinct versions of Seurat and Scanpy can produce very different results, especially during parts of differential expression analysis. Our analysis highlights the need for users of scRNA-seq to carefully assess the tools on which they rely, and the importance of developers of scientific software to prioritize transparency, consistency, and reproducibility for their tools.
]]></description>
<dc:creator>Rich, J. M.</dc:creator>
<dc:creator>Moses, L.</dc:creator>
<dc:creator>Einarsson, P. H.</dc:creator>
<dc:creator>Jackson, K.</dc:creator>
<dc:creator>Luebbert, L.</dc:creator>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Antonsson, S.</dc:creator>
<dc:creator>Sullivan, D. K.</dc:creator>
<dc:creator>Bray, N.</dc:creator>
<dc:creator>Melsted, P.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2024-04-05</dc:date>
<dc:identifier>doi:10.1101/2024.04.04.588111</dc:identifier>
<dc:title><![CDATA[The impact of package selection and versioning on single-cell RNA-seq analysis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-04-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.04.23.590787v1?rss=1">
<title>
<![CDATA[
Generation of a zebrafish neurofibromatosis model via inducible knockout of nf2 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.04.23.590787v1?rss=1</link>
<description><![CDATA[
Neurofibromatosis Type 2 (NF-2) is a dominantly inherited genetic disorder that results from mutations in the tumor suppressor gene, neurofibromin 2 (NF2) gene. Here, we report the generation of a conditional zebrafish model of neurofibromatosis established by an inducible genetic knockout of nf2a/b, the zebrafish homolog of human NF2. Analysis of nf2a and nf2b expression reveals ubiquitous expression of nf2b in the early embryo, with overlapping expression in the neural crest and its derivatives and in the cranial mesenchyme. In contrast, nf2a displays lower expression levels. Induction of nf2a/b knockout at early stages increases the proliferation of larval Schwann cells and meningeal fibroblasts. Subsequently, in adult zebrafish, nf2a/b knockout triggers the development of a spectrum of tumors, including vestibular schwannomas, spinal schwannomas, meningiomas, and retinal hamartomas, mirroring the tumor manifestations observed in patients with NF-2. Collectively, these findings highlight the generation of a novel zebrafish model that mimics the complexities of the human NF-2 disorder. Consequently, this model holds significant potential for facilitating therapeutic screening and elucidating key driver genes implicated in NF-2 onset.
]]></description>
<dc:creator>Desingu Rajan, A. R.</dc:creator>
<dc:creator>Huang, Y.</dc:creator>
<dc:creator>Stundl, J.</dc:creator>
<dc:creator>Irodi, A.</dc:creator>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Applegate, B. E.</dc:creator>
<dc:creator>Bronner, M.</dc:creator>
<dc:date>2024-04-27</dc:date>
<dc:identifier>doi:10.1101/2024.04.23.590787</dc:identifier>
<dc:title><![CDATA[Generation of a zebrafish neurofibromatosis model via inducible knockout of nf2]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-04-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.01.591941v1?rss=1">
<title>
<![CDATA[
Emergence of metabolic coupling to the heterotroph Alteromonas promotes dark survival in Prochlorococcus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.01.591941v1?rss=1</link>
<description><![CDATA[
Prochlorococcus is found throughout the euphotic zone in the oligotrophic open ocean. Deep mixing and sinking while attached to particles can, however, transport Prochlorococcus cells below this sunlit zone, depriving them of light for extended periods of time. Previous work has shown that Prochlorococcus by itself cannot survive extended periods of darkness. However, when co-cultured with a heterotrophic microbe and subjected to repeated periods of extended darkness, Prochlorococcus cells develop an epigenetically inherited dark-tolerant phenotype that can survive longer periods of darkness. Here we examine the metabolic and physiological changes underlying this adaptation using co-cultures of dark-tolerant and parental strains of Prochlorococcus, each grown with the heterotroph Alteromonas under diel light:dark conditions. The relative abundance of Alteromonas was higher in dark-tolerant than parental co-cultures, while dark-tolerant Prochlorococcus cells were larger, contained less chlorophyll, and were less synchronized to the light:dark cycle. Meta-transcriptome analysis revealed that dark-tolerant co-cultures undergo a joint change, in which Prochlorococcus undergoes a relative shift from photosynthesis to respiration, while Alteromonas shifts towards using more organic acids instead of sugars. Furthermore, the transcriptome data suggested enhanced biosynthesis of amino acids and purines in dark-tolerant Prochlorococcus and enhanced degradation of these compounds in Alteromonas. Collectively, our results demonstrate that dark adaptation involves a strengthening of the metabolic coupling between Prochlorococcus and Alteromonas, presumably mediated by an enhanced, and compositionally modified, carbon exchange between the two species.
]]></description>
<dc:creator>Coe, A.</dc:creator>
<dc:creator>Braakman, R.</dc:creator>
<dc:creator>Biller, S. J.</dc:creator>
<dc:creator>Arellano, A.</dc:creator>
<dc:creator>Bliem, C.</dc:creator>
<dc:creator>Vo, N. N.</dc:creator>
<dc:creator>von Emster, K.</dc:creator>
<dc:creator>Thomas, E.</dc:creator>
<dc:creator>DeMers, M.</dc:creator>
<dc:creator>Steglich, C.</dc:creator>
<dc:creator>Huisman, J.</dc:creator>
<dc:creator>Chisholm, S. W.</dc:creator>
<dc:date>2024-05-01</dc:date>
<dc:identifier>doi:10.1101/2024.05.01.591941</dc:identifier>
<dc:title><![CDATA[Emergence of metabolic coupling to the heterotroph Alteromonas promotes dark survival in Prochlorococcus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.06.592591v1?rss=1">
<title>
<![CDATA[
HisCl1 regulates gustatory habituation in sweet taste neurons and mediates sugar ingestion in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.06.592591v1?rss=1</link>
<description><![CDATA[
Similar to other animals, the fly, Drosophila melanogaster, reduces its responsiveness to tastants with repeated exposure, a phenomenon called gustatory habituation. Previous studies have focused on the circuit basis of gustatory habituation in the fly chemosensory system 1,2. However, gustatory neurons reduce their firing rate during repeated stimulation 3, suggesting that cell-autonomous mechanisms also contribute to habituation. Here, we used deep learning-based pose estimation and optogenetic stimulation to demonstrate that continuous activation of sweet taste neurons causes gustatory habituation in flies. We conducted a transgenic RNAi screen to identify genes involved in this process and found that knocking down Histamine-gated chloride channel subunit 1 (HisCl1) in the sweet taste neurons significantly reduced gustatory habituation. Anatomical analysis showed that HisCl1 is expressed in the sweet taste neurons of various chemosensory organs. Using single sensilla electrophysiology, we showed that sweet taste neurons reduced their firing rate with prolonged exposure to sucrose. Knocking down HisCl1 in sweet taste neurons suppressed gustatory habituation by reducing the spike frequency adaptation observed in these neurons during high-concentration sucrose stimulation. Finally, we showed that flies lacking HisCl1 in sweet taste neurons increased their consumption of high-concentration sucrose solution at their first meal bout compared to control flies. Together, our results demonstrate that HisCl1 tunes spike frequency adaptation in sweet taste neurons and contributes to gustatory habituation and food intake regulation in flies. Since HisCl1 is highly conserved across many dipteran and hymenopteran species, our findings open a new direction in studying insect gustatory habituation.
]]></description>
<dc:creator>Kim, H.</dc:creator>
<dc:creator>Zhong, Z.</dc:creator>
<dc:creator>Cui, X.</dc:creator>
<dc:creator>Sung, H.</dc:creator>
<dc:creator>Agrawal, N.</dc:creator>
<dc:creator>Jiang, T.</dc:creator>
<dc:creator>Dus, M.</dc:creator>
<dc:creator>Yapici, N.</dc:creator>
<dc:date>2024-05-08</dc:date>
<dc:identifier>doi:10.1101/2024.05.06.592591</dc:identifier>
<dc:title><![CDATA[HisCl1 regulates gustatory habituation in sweet taste neurons and mediates sugar ingestion in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.06.592821v1?rss=1">
<title>
<![CDATA[
Machine learning models can identify individuals based on a resident oral bacteriophage family 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.06.592821v1?rss=1</link>
<description><![CDATA[
Metagenomic studies have revolutionized the study of novel phages. However these studies trade depth of coverage for breadth. We show that the targeted sequencing of a small region of a phage terminase family can provide sufficient sequence diversity to serve as an individual-specific barcode or a "phageprint, defined as the relative abundance profile of the variants within a terminase family. By collecting [~]700 oral samples from [~]100 individuals living on multiple continents, we found a consistent trend wherein each individual harbors one or two dominant variants that coexist with numerous low-abundance variants. By tracking phageprints over the span of a month across ten individuals, we observed that phageprints were generally stable, and found instances of concordant temporal fluctuations of variants shared between partners. To quantify these patterns further, we built machine learning models that, with high precision and recall, distinguished individuals even when we eliminated the most abundant variants and further downsampled phageprints to 2% of the remaining variants. Except between partners, phageprints are dissimilar between individuals, and neither country-of-residence, genetics, diet nor cohabitation seem to play a role in the relatedness of phageprints across individuals. By sampling from six different oral sites, we were able to study the impact of millimeters to a few centimeters of separation on an individuals phageprint and found that such limited spatial separation results in site-specific phageprints.
]]></description>
<dc:creator>Mahmoudabadi, G.</dc:creator>
<dc:creator>Homyk, K.</dc:creator>
<dc:creator>Catching, A.</dc:creator>
<dc:creator>Mahmoudabadi, A.</dc:creator>
<dc:creator>Foley, H. B.</dc:creator>
<dc:creator>Tadmor, A. D.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2024-05-08</dc:date>
<dc:identifier>doi:10.1101/2024.05.06.592821</dc:identifier>
<dc:title><![CDATA[Machine learning models can identify individuals based on a resident oral bacteriophage family]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.07.593011v1?rss=1">
<title>
<![CDATA[
The microbiome shapes immunity in a sex-specific manner in mouse models of Alzheimer's disease 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.07.593011v1?rss=1</link>
<description><![CDATA[
INTRODUCTION: Preclinical studies reveal that the microbiome broadly affects immune responses and deposition and/or clearance of amyloid-beta (A{beta}) in mouse models of Alzheimers disease (AD). Whether the microbiome shapes central and peripheral immune profiles in AD models remains unknown.

METHODS: We examined adaptive immune responses in two mouse models containing AD- related genetic predispositions (3xTg and 5xFAD) in the presence or absence of the microbiome.

RESULTS: T and B cells were altered in brain-associated and systemic immune tissues between genetic models and wildtype mice, with earlier signs of immune activity in females. Systemic immune responses were modulated by the microbiome and differed by sex. Further, the absence of a microbiome in germ-free mice resulted in reduced cognitive deficits, primarily in females.

DISCUSSION: These data reveal sexual dimorphism in early signs of immune activity and microbiome effects, and highlight an interesting interaction between sex and the microbiome in mouse models of AD.
]]></description>
<dc:creator>Bostick, J. W.</dc:creator>
<dc:creator>Connerly, T. J.</dc:creator>
<dc:creator>Thron, T.</dc:creator>
<dc:creator>Needham, B. D.</dc:creator>
<dc:creator>de Castro Fonseca, M.</dc:creator>
<dc:creator>Kaddurah-Daouk, R.</dc:creator>
<dc:creator>Knight, R.</dc:creator>
<dc:creator>Mazmanian, S. K.</dc:creator>
<dc:date>2024-05-08</dc:date>
<dc:identifier>doi:10.1101/2024.05.07.593011</dc:identifier>
<dc:title><![CDATA[The microbiome shapes immunity in a sex-specific manner in mouse models of Alzheimer's disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.10.593654v1?rss=1">
<title>
<![CDATA[
Ultrasound-actuated drug delivery with acoustic percolation switches 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.10.593654v1?rss=1</link>
<description><![CDATA[
Devices that can be remote-controlled under image guidance to precisely deliver biomedicines to sites of disease are a major goal of biomedical research. However, most existing externally triggered delivery systems are based on complex micromachines that are controlled with electromagnetic waves and require custom external instrumentation. Here we present a drug delivery platform comprising a simple protein-containing hydrogel that can be both imaged and triggered to release drugs at specific locations using widely available ultrasound imaging devices. This technology is based on the addition of air-filled protein nanostructures called gas vesicles (GVs) to hydrogel delivery vehicles. While intact, GVs sterically block the release of drug payloads and allow the vehicle to be imaged with ultrasound. An increase in ultrasound pressure causes the collapse of GVs within hydrogels present at the desired anatomical location, instantly creating percolation channels and triggering rapid drug release. Both the imaging and release are performed using a common diagnostic ultrasound probe. We implement this concept by establishing ultrasound-controlled drug diffusion and release from hydrogels in vitro and demonstrating targeted image-guided protein delivery in vivo following oral administration. We use this approach to deliver anti-inflammatory antibodies to treat gastrointestinal inflammation in a rat model of colitis. Targeted acoustic percolation switches (TAPS) open a conduit for local, image-guided drug delivery with a simple formulation and commonplace ultrasound equipment.
]]></description>
<dc:creator>Abundo, M. P.</dc:creator>
<dc:creator>Tifrea, A. T.</dc:creator>
<dc:creator>Buss, M. T.</dc:creator>
<dc:creator>Barturen-Larrea, P.</dc:creator>
<dc:creator>Jin, Z.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2024-05-14</dc:date>
<dc:identifier>doi:10.1101/2024.05.10.593654</dc:identifier>
<dc:title><![CDATA[Ultrasound-actuated drug delivery with acoustic percolation switches]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.13.593529v1?rss=1">
<title>
<![CDATA[
Visual context affects the perceived timing of tactile sensations elicited through intra-cortical microstimulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.13.593529v1?rss=1</link>
<description><![CDATA[
Intra-cortical microstimulation (ICMS) is a technique to provide tactile sensations for a somatosensory brain-machine interface (BMI). A viable BMI must function within the rich, multisensory environment of the real world, but how ICMS is integrated with other sensory modalities is poorly understood. To investigate how ICMS percepts are integrated with visual information, ICMS and visual stimuli were delivered at varying times relative to one another. Both visual context and ICMS current amplitude were found to bias the qualitative experience of ICMS. In two tetraplegic participants, ICMS and visual stimuli were more likely to be experienced as occurring simultaneously when visual stimuli were more realistic, demonstrating an effect of visual context on the temporal binding window. The peak of the temporal binding window varied but was consistently offset from zero, suggesting that multisensory integration with ICMS can suffer from temporal misalignment. Recordings from primary somatosensory cortex (S1) during catch trials where visual stimuli were delivered without ICMS demonstrated that S1 represents visual information related to ICMS across visual contexts.
]]></description>
<dc:creator>Rosenthal, I. A.</dc:creator>
<dc:creator>Bashford, L.</dc:creator>
<dc:creator>Bjanes, D.</dc:creator>
<dc:creator>Pejsa, K.</dc:creator>
<dc:creator>Lee, B.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2024-05-14</dc:date>
<dc:identifier>doi:10.1101/2024.05.13.593529</dc:identifier>
<dc:title><![CDATA[Visual context affects the perceived timing of tactile sensations elicited through intra-cortical microstimulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.13.594011v1?rss=1">
<title>
<![CDATA[
Flavin-containing siderophore-interacting protein of Shewanella putrefaciens DSM 9451 reveals substrate specificity in ferric-siderophore reduction 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.13.594011v1?rss=1</link>
<description><![CDATA[
Shewanella are bacteria widespread in marine and brackish water environments and emergent opportunistic pathogens. Their environmental versatility is highly dependent on the ability to produce an abundance of iron-rich proteins, mainly multiheme c-type cytochromes. Although iron plays a vital role in the ability of Shewanella species to survive in various environments, very few studies exist regarding the strategies by which these bacteria scavenge iron from the environment. Small molecule siderophore-mediated iron transport is a strategy commonly employed for iron acquisition, and it was identified amongst Shewanella spp. over two decades ago. Shewanella species produce hydroxamate-type siderophores and iron removal from these compounds can occur in the cytoplasm via Fe(III)-siderophore reduction mediated by siderophore-interacting proteins (SIPs). The genome of Shewanella putrefaciens DSM 9451 isolated from an infected child contains representatives of the two different cytosolic families of SIPs: the flavin-containing siderophore interacting protein family (SIP) and the iron-sulfur cluster-containing ferric siderophore reductase family (FSR).

Here, we report the expression and purification of the flavin-containing (SbSIP) and iron-sulfur cluster-containing (SbFSR) Fe(III)-siderophore reductases of Shewanella putrefaciens DSM 9451. The structural and functional characterization of SbSIP shows distinct features from the highly homologous SIP from Shewanella frigidimarina (SfSIP). These include significant structural differences, different binding affinities for NADH and NADPH, and lower rates of Fe(III)-siderophore reduction, results which consolidate in the putative identification of the binding pocket for these proteins.

Overall our work highlights NADH and NADPH specificity and the different Fe(III)- siderophore reduction abilities of the SIP family suggesting a tailoring of these enzymes towards meeting different microbial iron requirements.
]]></description>
<dc:creator>Trindade, I. B.</dc:creator>
<dc:creator>Fonseca, B. M.</dc:creator>
<dc:creator>Catarino, T.</dc:creator>
<dc:creator>Matias, P. M.</dc:creator>
<dc:creator>Moe, E.</dc:creator>
<dc:creator>Louro, R. O.</dc:creator>
<dc:date>2024-05-13</dc:date>
<dc:identifier>doi:10.1101/2024.05.13.594011</dc:identifier>
<dc:title><![CDATA[Flavin-containing siderophore-interacting protein of Shewanella putrefaciens DSM 9451 reveals substrate specificity in ferric-siderophore reduction]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.14.594235v1?rss=1">
<title>
<![CDATA[
Mapping Endothelial-Macrophage Interactions in Diabetic Vasculature: Role of TREM2 in Vascular Inflammation and Ischemic Response 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.14.594235v1?rss=1</link>
<description><![CDATA[
Diabetes mellitus (DM) significantly accelerates vascular diseases like peripheral arterial disease (PAD). Endothelial cells (ECs) and macrophages (M{Phi}s) singularly and synergistically are important contributors to DM-associated vascular dysfunction. Single-cell (sc) profiling technologies are revealing the true heterogeneity of ECs and M{Phi}s, but how this cellular diversity translates to cell-cell interactions, and consequentially vascular function, remains unknown. We leveraged scRNA sequencing and spatial transcriptome (ST) profiling to analyze human mesenteric arteries from non-diabetic (ND) and type 2 diabetic (T2D) donors. We generated a transcriptome and interactome map encompassing the major arterial cells and highlighted Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) as a top T2D-induced gene in mononuclear phagocytes (MPs), with concomitant increases of TREM2 ligands in ECs. We verified DM-associated TREM2 induction in cell and mouse models, and found that TREM2 inhibition decreases pro-inflammatory responses in MPs and ECs, as well as increases EC migration in vitro. Furthermore, TREM2 inhibition using a neutralizing antibody enhanced ischemic recovery and flow reperfusion in DM mice subjected to hindlimb ischemia, suggesting that TREM2 promotes ischemic injury in DM. Finally, in human PAD, co-existing DM was associated with greater expression of TREM2 and its interaction with ECs, with a further increase in ischemic tissue compared to patient-matched non-ischemic tissue. Collectively, our study presents the first atlas of human diabetic vessels with single cell and spatial resolution, and identifies TREM2-EC interaction as a key driver of diabetic vasculopathies, the targeting of which may offer an opportunity to ameliorate vascular dysfunction associated with DM-PAD.
]]></description>
<dc:creator>Malhi, N. K.</dc:creator>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>Tang, X.</dc:creator>
<dc:creator>Chadha, R. S.</dc:creator>
<dc:creator>Tapia, A.</dc:creator>
<dc:creator>Liu, X.</dc:creator>
<dc:creator>Chen, M.</dc:creator>
<dc:creator>Yuan, D.</dc:creator>
<dc:creator>Qi, M.</dc:creator>
<dc:creator>Wei, L.</dc:creator>
<dc:creator>Cooke, J. P.</dc:creator>
<dc:creator>Natarajan, R.</dc:creator>
<dc:creator>Southerland, K. W.</dc:creator>
<dc:creator>Chen, Z. B.</dc:creator>
<dc:date>2024-05-17</dc:date>
<dc:identifier>doi:10.1101/2024.05.14.594235</dc:identifier>
<dc:title><![CDATA[Mapping Endothelial-Macrophage Interactions in Diabetic Vasculature: Role of TREM2 in Vascular Inflammation and Ischemic Response]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.17.594333v1?rss=1">
<title>
<![CDATA[
Stable, chronic in-vivo recordings from a fully wireless subdural-contained 65,536-electrode brain-computer interface device 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.17.594333v1?rss=1</link>
<description><![CDATA[
Minimally invasive, high-bandwidth brain-computer-interface (BCI) devices can revolutionize human applications. With orders-of-magnitude improvements in volumetric efficiency over other BCI technologies, we developed a 50-m-thick, mechanically flexible micro-electrocorticography (ECoG) BCI, integrating a 256x256 array of electrodes, signal processing, data telemetry, and wireless powering on a single complementary metal-oxide-semiconductor (CMOS) substrate containing 65,536 recording channels, from which we can simultaneously record a selectable subset of up to 1024 channels at a given time. Fully implanted below the dura, our chip is wirelessly powered, communicating bi-directionally with an external relay station outside the body. We demonstrated chronic, reliable recordings for up to two weeks in pigs and up to two months in behaving non-human primates from somatosensory, motor, and visual cortices, decoding brain signals at high spatiotemporal resolution.
]]></description>
<dc:creator>Jung, T.</dc:creator>
<dc:creator>Zeng, N.</dc:creator>
<dc:creator>Fabbri, J. D.</dc:creator>
<dc:creator>Eichler, G.</dc:creator>
<dc:creator>Li, Z.</dc:creator>
<dc:creator>Willeke, K.</dc:creator>
<dc:creator>Wingel, K. E.</dc:creator>
<dc:creator>Dubey, A.</dc:creator>
<dc:creator>Huq, R.</dc:creator>
<dc:creator>Sharma, M.</dc:creator>
<dc:creator>Hu, Y.</dc:creator>
<dc:creator>Ramakrishnan, G.</dc:creator>
<dc:creator>Tien, K.</dc:creator>
<dc:creator>Mantovani, P.</dc:creator>
<dc:creator>Parihar, A.</dc:creator>
<dc:creator>Yin, H.</dc:creator>
<dc:creator>Oswalt, D.</dc:creator>
<dc:creator>Misdorp, A.</dc:creator>
<dc:creator>Uguz, I.</dc:creator>
<dc:creator>Shinn, T.</dc:creator>
<dc:creator>Rodriguez, G. J.</dc:creator>
<dc:creator>Nealley, C.</dc:creator>
<dc:creator>Gonzales, I.</dc:creator>
<dc:creator>Roukes, M.</dc:creator>
<dc:creator>Knecht, J.</dc:creator>
<dc:creator>Yoshor, D.</dc:creator>
<dc:creator>Canoll, P.</dc:creator>
<dc:creator>Spinazzi, E.</dc:creator>
<dc:creator>Carloni, L. P.</dc:creator>
<dc:creator>Pesaran, B.</dc:creator>
<dc:creator>Patel, S.</dc:creator>
<dc:creator>Youngerman, B.</dc:creator>
<dc:creator>Cotton, R. J.</dc:creator>
<dc:creator>Tolias, A.</dc:creator>
<dc:creator>Shepard, K. L.</dc:creator>
<dc:date>2024-05-17</dc:date>
<dc:identifier>doi:10.1101/2024.05.17.594333</dc:identifier>
<dc:title><![CDATA[Stable, chronic in-vivo recordings from a fully wireless subdural-contained 65,536-electrode brain-computer interface device]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.18.594613v1?rss=1">
<title>
<![CDATA[
Long-term imaging of three-dimensional hyphal development using the ePetri dish 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.18.594613v1?rss=1</link>
<description><![CDATA[
Imaging three-dimensional microbial development and behavior over extended periods is crucial for advancing microbiological studies. Here, we introduce an upgraded ePetri dish system specifically designed for extended microbial culturing and 3D imaging, addressing the limitations of existing methods. Our approach includes a sealed growth chamber to enable long-term culturing, and a multi-step reconstruction algorithm that integrates 3D deconvolution, image filtering, ridge, and skeleton detection for detailed visualization of the hyphal network. The system effectively monitored the development of Aspergillus brasiliensis hyphae over a seven-day period, demonstrating the growth mediums stability within the chamber. The systems 3D imaging capability was validated in a volume of 5.5 mm x 4 mm x 0.5 mm, revealing a radial growth pattern of fungal hyphae. Additionally, we show that the system can identify potential filter failures that are undetectable with 2D imaging. With these capabilities, the upgraded ePetri dish represents a significant advancement in long-term 3D microbial imaging, promising new insights into microbial development and behavior across various microbiological research areas.
]]></description>
<dc:creator>Zhang, O.</dc:creator>
<dc:creator>Dahlquist, N.</dc:creator>
<dc:creator>Leete, Z.</dc:creator>
<dc:creator>Xu, M.</dc:creator>
<dc:creator>Schneider, D.</dc:creator>
<dc:creator>Yang, C.</dc:creator>
<dc:date>2024-05-19</dc:date>
<dc:identifier>doi:10.1101/2024.05.18.594613</dc:identifier>
<dc:title><![CDATA[Long-term imaging of three-dimensional hyphal development using the ePetri dish]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.20.595009v1?rss=1">
<title>
<![CDATA[
Target gene responses differ when transcription factor levels are acutely decreased by nuclear export versus degradation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.20.595009v1?rss=1</link>
<description><![CDATA[
Defining the time of action for morphogens requires tools capable of temporally controlled perturbations. To study how the transcription factor Dorsal affects patterning of the Drosophila embryonic dorsal-ventral axis, we used two light-inducible tags that result in either nuclear export or degradation of Dorsal when exposed to blue light. Nuclear export of Dorsal results in loss of expression for the high threshold, ventrally-expressed target gene snail (sna) but retention of the low threshold, laterally-expressed target gene short-gastrulation (sog). In contrast, degradation of Dorsal results in retention of sna, loss of sog, and lower nuclear levels than when Dorsal is exported from the nucleus. To elucidate how nuclear export results in loss of sna but degradation does not, we investigated Dorsal kinetics using photobleaching and found it reenters the nucleus even under conditions of blue-light when export is favored. The associated kinetics of being imported and exported continuously are likely responsible for loss of sna but, alternatively, can support sog. Collectively, our results show that this dynamic patterning process is influenced by both Dorsal concentration and nuclear retention.

SUMMARY STATEMENTThis study shows how optogenetic tools can be used to determine how a transcription factors levels and nuclear retention impact a dynamic patterning process.
]]></description>
<dc:creator>McGehee, J.</dc:creator>
<dc:creator>Stathopoulos, A.</dc:creator>
<dc:date>2024-05-20</dc:date>
<dc:identifier>doi:10.1101/2024.05.20.595009</dc:identifier>
<dc:title><![CDATA[Target gene responses differ when transcription factor levels are acutely decreased by nuclear export versus degradation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.21.595051v1?rss=1">
<title>
<![CDATA[
Intrinsic dynamics and neural implementation of a hypothalamic line attractor encoding an internal behavioral state 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.21.595051v1?rss=1</link>
<description><![CDATA[
Line attractors are emergent population dynamics hypothesized to encode continuous variables such as head direction and internal states. In mammals, direct evidence of neural implementation of a line attractor has been hindered by the challenge of targeting perturbations to specific neurons within contributing ensembles. Estrogen receptor type 1 (Esr1)-expressing neurons in the ventrolateral subdivision of the ventromedial hypothalamus (VMHvl) show line attractor dynamics in male mice during fighting. We hypothesized that these dynamics may encode continuous variation in the intensity of an internal aggressive state. Here, we report that these neurons also show line attractor dynamics in head-fixed mice observing aggression. We exploit this finding to identify and perturb line attractor-contributing neurons using 2-photon calcium imaging and holographic optogenetic perturbations. On-manifold perturbations demonstrate that integration and persistent activity are intrinsic properties of these neurons which drive the system along the line attractor, while transient off-manifold perturbations reveal rapid relaxation back into the attractor. Furthermore, stimulation and imaging reveal selective functional connectivity among attractor-contributing neurons. Intriguingly, individual differences among mice in line attractor stability were correlated with the degree of functional connectivity among contributing neurons. Mechanistic modelling indicates that dense subnetwork connectivity and slow neurotransmission are required to explain our empirical findings. Our work bridges circuit and manifold paradigms, shedding light on the intrinsic and operational dynamics of a behaviorally relevant mammalian line attractor.
]]></description>
<dc:creator>Vinograd, A.</dc:creator>
<dc:creator>Nair, A.</dc:creator>
<dc:creator>Linderman, S. W.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:date>2024-05-22</dc:date>
<dc:identifier>doi:10.1101/2024.05.21.595051</dc:identifier>
<dc:title><![CDATA[Intrinsic dynamics and neural implementation of a hypothalamic line attractor encoding an internal behavioral state]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.05.23.595576v1?rss=1">
<title>
<![CDATA[
Norepinephrine changes behavioral state via astroglial purinergic signaling 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.05.23.595576v1?rss=1</link>
<description><![CDATA[
Both neurons and glia communicate via diffusible neuromodulatory substances, but the substrates of computation in such neuromodulatory networks are unclear. During behavioral transitions in the larval zebrafish, the neuromodulator norepinephrine drives fast excitation and delayed inhibition of behavior and circuit activity. We find that the inhibitory arm of this feedforward motif is implemented by astroglial purinergic signaling. Neuromodulator imaging, behavioral pharmacology, and perturbations of neurons and astroglia reveal that norepinephrine triggers astroglial release of adenosine triphosphate, extracellular conversion into adenosine, and behavioral suppression through activation of hindbrain neuronal adenosine receptors. This work, along with a companion piece by Lefton and colleagues demonstrating an analogous pathway mediating the effect of norepinephrine on synaptic connectivity in mice, identifies a computational and behavioral role for an evolutionarily conserved astroglial purinergic signaling axis in norepinephrine-mediated behavioral and brain state transitions.
]]></description>
<dc:creator>Chen, A. B.</dc:creator>
<dc:creator>Duque, M.</dc:creator>
<dc:creator>Wang, V. M.</dc:creator>
<dc:creator>Dhanasekar, M.</dc:creator>
<dc:creator>Mi, X.</dc:creator>
<dc:creator>Rymbek, A.</dc:creator>
<dc:creator>Tocquer, L.</dc:creator>
<dc:creator>Narayan, S.</dc:creator>
<dc:creator>Prober, D. A.</dc:creator>
<dc:creator>Yu, G.</dc:creator>
<dc:creator>Wyart, C.</dc:creator>
<dc:creator>Engert, F.</dc:creator>
<dc:creator>Ahrens, M. B.</dc:creator>
<dc:date>2024-05-23</dc:date>
<dc:identifier>doi:10.1101/2024.05.23.595576</dc:identifier>
<dc:title><![CDATA[Norepinephrine changes behavioral state via astroglial purinergic signaling]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-05-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.06.02.597062v1?rss=1">
<title>
<![CDATA[
Automated classification of cellular expression in multiplexed imaging data with Nimbus 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.06.02.597062v1?rss=1</link>
<description><![CDATA[
Multiplexed imaging offers a powerful approach to characterize the spatial topography of tissues in both health and disease. To analyze such data, the specific combination of markers that are present in each cell must be enumerated to enable accurate phenotyping, a process that often relies on unsupervised clustering. We constructed the Pan-Multiplex (Pan-M) dataset containing 197 million distinct annotations of marker expression across 15 different cell types. We used Pan-M to create Nimbus, a deep learning model to predict marker positivity from multiplexed image data. Nimbus is a pre-trained model that uses the underlying images to classify marker expression across distinct cell types, from different tissues, acquired using different microscope platforms, without requiring any retraining. We demonstrate that Nimbus predictions capture the underlying staining patterns of the full diversity of markers present in Pan-M. We then show how Nimbus predictions can be integrated with downstream clustering algorithms to robustly identify cell subtypes in image data. We have open-sourced Nimbus and Pan-M to enable community use at https://github.com/angelolab/Nimbus-Inference.
]]></description>
<dc:creator>Rumberger, L.</dc:creator>
<dc:creator>Greenwald, N. F.</dc:creator>
<dc:creator>Ranek, J.</dc:creator>
<dc:creator>Boonrat, P.</dc:creator>
<dc:creator>Walker, C.</dc:creator>
<dc:creator>Franzen, J.</dc:creator>
<dc:creator>Varra, S.</dc:creator>
<dc:creator>Kong, A.</dc:creator>
<dc:creator>Sowers, C.</dc:creator>
<dc:creator>Liu, C. C.</dc:creator>
<dc:creator>Averbukh, I.</dc:creator>
<dc:creator>Piyadasa, H.</dc:creator>
<dc:creator>Vanguri, R.</dc:creator>
<dc:creator>Nederlof, I.</dc:creator>
<dc:creator>Wang, X. J.</dc:creator>
<dc:creator>Van Valen, D. A.</dc:creator>
<dc:creator>Kok, M.</dc:creator>
<dc:creator>Hollmann, T. J.</dc:creator>
<dc:creator>Kainmueller, D.</dc:creator>
<dc:creator>Angelo, M.</dc:creator>
<dc:date>2024-06-03</dc:date>
<dc:identifier>doi:10.1101/2024.06.02.597062</dc:identifier>
<dc:title><![CDATA[Automated classification of cellular expression in multiplexed imaging data with Nimbus]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-06-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.06.07.597975v1?rss=1">
<title>
<![CDATA[
α-Synuclein Overexpression and the Microbiome Shape the Gut and Brain Metabolome in Mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.06.07.597975v1?rss=1</link>
<description><![CDATA[
Pathological forms of the protein -synuclein contribute to a family of disorders termed synucleinopathies, which includes Parkinsons disease (PD). Most cases of PD are believed to arise from gene-environment interactions. Microbiome composition is altered in PD, and gut bacteria are causal to symptoms and pathology in animal models. To explore how the microbiome may impact PD-associated genetic risks, we quantitatively profiled nearly 630 metabolites from 26 biochemical classes in the gut, plasma, and brain of -synuclein-overexpressing (ASO) mice with or without microbiota. We observe tissue-specific changes driven by genotype, microbiome, and their interaction. Many differentially expressed metabolites in ASO mice are also dysregulated in human PD patients, including amine oxides, bile acids and indoles. Notably, levels of the microbial metabolite trimethylamine N-oxide (TMAO) strongly correlate from the gut to the plasma to the brain, identifying a product of gene-environment interactions that may influence PD-like outcomes in mice. TMAO is elevated in the blood and cerebral spinal fluid of PD patients. These findings uncover broad metabolomic changes that are influenced by the intersection of host genetics and the microbiome in a mouse model of PD.
]]></description>
<dc:creator>Morais, L. H.</dc:creator>
<dc:creator>Boktor, J. C.</dc:creator>
<dc:creator>MahmoudianDehkordi, S.</dc:creator>
<dc:creator>Kaddurah-Daouk, R.</dc:creator>
<dc:creator>Mazmanian, S. K.</dc:creator>
<dc:date>2024-06-10</dc:date>
<dc:identifier>doi:10.1101/2024.06.07.597975</dc:identifier>
<dc:title><![CDATA[α-Synuclein Overexpression and the Microbiome Shape the Gut and Brain Metabolome in Mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-06-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.06.10.598133v1?rss=1">
<title>
<![CDATA[
Congenital heart defects differ following left versus right avian cardiac neural crest ablation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.06.10.598133v1?rss=1</link>
<description><![CDATA[
The cardiac neural crest is critical for the normal development of the heart, as its surgical ablation in the chick recapitulates common human congenital heart defects such as  Common Arterial Trunk and  Double Outlet Right Ventricle (DORV). While left-right asymmetry is known to be important for heart development, little is known about potential asymmetric differences between right and left cardiac neural folds with respect to heart development. Here, through surgical ablation of either left or right cardiac neural crest, we find that right ablation results in more varied and more severe heart defects. Embryos with Common Arterial Trunk and with missing arteries occurred in right-ablated embryos but were not observed in left-ablated embryos; moreover, embryos with DORV and with misalignment of the arteries were more prevalent following right versus left cardiac crest ablation. In addition, survival of right-ablated embryos was lower than left-ablated embryos. Together, these data raise the intriguing possibility that there may be differences in left versus right cardiac neural crest during heart development.
]]></description>
<dc:creator>Solovieva, T.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:date>2024-06-10</dc:date>
<dc:identifier>doi:10.1101/2024.06.10.598133</dc:identifier>
<dc:title><![CDATA[Congenital heart defects differ following left versus right avian cardiac neural crest ablation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-06-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.06.12.598567v1?rss=1">
<title>
<![CDATA[
The ENCODE mouse postnatal developmental time course identifies regulatory programs of cell types and cell states 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.06.12.598567v1?rss=1</link>
<description><![CDATA[
Postnatal genomic regulation significantly influences tissue and organ maturation but is under-studied relative to existing genomic catalogs of adult tissues or prenatal development in mouse. The ENCODE4 consortium generated the first comprehensive single-nucleus resource of postnatal regulatory events across a diverse set of mouse tissues. The collection spans seven postnatal time points, mirroring human development from childhood to adulthood, and encompasses five core tissues. We identified 30 cell types, further subdivided into 69 subtypes and cell states across adrenal gland, left cerebral cortex, hippocampus, heart, and gastrocnemius muscle. Our annotations cover both known and novel cell differentiation dynamics ranging from early hippocampal neurogenesis to a new sex-specific adrenal gland population during puberty. We used an ensemble Latent Dirichlet Allocation strategy with a curated vocabulary of 2,701 regulatory genes to identify regulatory "topics," each of which is a gene vector, linked to cell type differentiation, subtype specialization, and transitions between cell states. We find recurrent regulatory topics in tissue-resident macrophages, neural cell types, endothelial cells across multiple tissues, and cycling cells of the adrenal gland and heart. Cell-type-specific topics are enriched in transcription factors and microRNA host genes, while chromatin regulators dominate mitosis topics. Corresponding chromatin accessibility data reveal dynamic and sex-specific regulatory elements, with enriched motifs matching transcription factors in regulatory topics. Together, these analyses identify both tissue-specific and common regulatory programs in postnatal development across multiple tissues through the lens of the factors regulating transcription.
]]></description>
<dc:creator>Rebboah, E.</dc:creator>
<dc:creator>Rezaie, N.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>Weimer, A. K.</dc:creator>
<dc:creator>Shi, M.</dc:creator>
<dc:creator>Yang, X.</dc:creator>
<dc:creator>Liang, H. Y.</dc:creator>
<dc:creator>Dionne, L.</dc:creator>
<dc:creator>Reese, F.</dc:creator>
<dc:creator>Trout, D.</dc:creator>
<dc:creator>Jou, J.</dc:creator>
<dc:creator>Youngworth, I.</dc:creator>
<dc:creator>Reinholdt, L. G.</dc:creator>
<dc:creator>Morabito, S.</dc:creator>
<dc:creator>Snyder, M.</dc:creator>
<dc:creator>Wold, B.</dc:creator>
<dc:creator>Mortazavi, A.</dc:creator>
<dc:date>2024-06-14</dc:date>
<dc:identifier>doi:10.1101/2024.06.12.598567</dc:identifier>
<dc:title><![CDATA[The ENCODE mouse postnatal developmental time course identifies regulatory programs of cell types and cell states]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-06-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.06.12.598716v1?rss=1">
<title>
<![CDATA[
Escalation of genome defense capacity enables control of an expanding meiotic driver 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.06.12.598716v1?rss=1</link>
<description><![CDATA[
SummaryFrom RNA interference to chromatin silencing, diverse genome defense pathways silence selfish genetic elements to safeguard genome integrity1,2. Despite their diversity, different defense pathways share a modular organization, where numerous specificity factors identify diverse targets and common effectors silence them. In the PIWI-interacting RNA (piRNA) pathway, which controls selfish elements in the metazoan germline, diverse target RNAs are first identified by complementary base pairing with piRNAs and then silenced by PIWI-clade nucleases via enzymatic cleavage1,3. Such a binary architecture allows the defense systems to be readily adaptable, where new targets can be captured via the innovation of new specificity factors4,5. Thus, our current understanding of genome defense against lineage-specific selfish genes has been largely limited to the evolution of specificity factors, while it remains poorly understood whether other types of innovations are required. Here, we describe a new type of innovation, which escalates the defense capacity of the piRNA pathway to control a recently expanded selfish gene in Drosophila melanogaster. Through an in vivo RNAi screen for repressors of Stellate--a recently evolved and expanded selfish meiotic driver6-8--we discovered a novel defense factor, Trailblazer. Trailblazer is a transcription factor that promotes the expression of two PIWI-clade nucleases, Aub and AGO3, to match Stellate in abundance. Recent innovation in the DNA-binding domain of Trailblazer enabled it to drastically elevate Aub and AGO3 expression in the D. melanogaster lineage, thereby escalating the silencing capacity of the piRNA pathway to control expanded Stellate and safeguard fertility. As copy-number expansion is a recurrent feature of diverse selfish genes across the tree of life9-12, we envision that augmenting the defense capacity to quantitatively match selfish genes is likely a repeatedly employed defense strategy in evolution.
]]></description>
<dc:creator>Chen, P.</dc:creator>
<dc:creator>Pan, K. C.</dc:creator>
<dc:creator>Park, E. H.</dc:creator>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>Lee, G. Y. C.</dc:creator>
<dc:creator>Aravin, A. A.</dc:creator>
<dc:date>2024-06-14</dc:date>
<dc:identifier>doi:10.1101/2024.06.12.598716</dc:identifier>
<dc:title><![CDATA[Escalation of genome defense capacity enables control of an expanding meiotic driver]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-06-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.06.16.599229v1?rss=1">
<title>
<![CDATA[
Low-dimensional olfactory signatures of fruit ripening and fermentation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.06.16.599229v1?rss=1</link>
<description><![CDATA[
Odors provide an important communication channel between plants and animals. Fruits, vital nutrient sources for animals, emit a complex array of monomolecular volatiles. Animals can use the structure of these mixtures to assess properties of fruit predictive of their nutritive and reproductive value. We analyzed the statistics of fruit odor mixtures sampled across stages of ripening and fermentation to find that they fall on a low-dimensional hyperbolic map. Hyperbolic maps, with their negative curvature and an exponentially expanding state options, are adept at describing hierarchical relationships in the data such as those arising from metabolic processes within fruits. In the hyperbolic map, samples followed a striking spiral trajectory. The spiral initiated near the maps core, representing the under-ripe phase with specific profiles of monomolecular volatiles. Progressively mapping along the unfolding spiral trajectory were scent mixtures corresponding to ripening, and then rotting or fermentation. The unfolding process depended on the specific fermentation processes that dominated in the samples, determined largely by the microbes (e.g. bacteria or yeast) present in the sample. These results generalized across fruit types and describe trajectories in the natural odorant space with significant behavioral relevance for insects.
]]></description>
<dc:creator>Zhou, Y.</dc:creator>
<dc:creator>O'Connell, T. F.</dc:creator>
<dc:creator>Ghaninia, M.</dc:creator>
<dc:creator>Smith, B.</dc:creator>
<dc:creator>Hong, E. J.</dc:creator>
<dc:creator>Sharpee, T. O.</dc:creator>
<dc:date>2024-06-17</dc:date>
<dc:identifier>doi:10.1101/2024.06.16.599229</dc:identifier>
<dc:title><![CDATA[Low-dimensional olfactory signatures of fruit ripening and fermentation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-06-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.06.23.600144v1?rss=1">
<title>
<![CDATA[
A combinatorially complete epistatic fitness landscape in an enzyme active site 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.06.23.600144v1?rss=1</link>
<description><![CDATA[
Protein engineering often targets binding pockets or active sites which are enriched in epistasis-- non-additive interactions between amino acid substitutions--and where the combined effects of multiple single substitutions are difficult to predict. Few existing sequence-fitness datasets capture epistasis at large scale, especially for enzyme catalysis, limiting the development and assessment of model-guided enzyme engineering approaches. We present here a combinatorially complete, 160,000-variant fitness landscape across four residues in the active site of an enzyme. Assaying the native reaction of a thermostable {beta}-subunit of tryptophan synthase (TrpB) in a non-native environment yielded a landscape characterized by significant epistasis and many local optima. These effects prevent simulated directed evolution approaches from efficiently reaching the global optimum. There is nonetheless wide variability in the effectiveness of different directed evolution approaches, which together provide experimental benchmarks for computational and machine learning workflows. The most-fit TrpB variants contain a substitution that is nearly absent in natural TrpB sequences--a result that conservation-based predictions would not capture. Thus, although fitness prediction using evolutionary data can enrich in more-active variants, these approaches struggle to identify and differentiate among the most-active variants, even for this near-native function. Overall, this work presents a new, large-scale testing ground for model-guided enzyme engineering and suggests that efficient navigation of epistatic fitness landscapes can be improved by advances in both machine learning and physical modeling.

Significance statementPredictive models for protein engineering seek to capture the relationship between protein sequence and function. While many methods and datasets exist for predicting the effects of single substitutions across a range of protein functions, fewer capture interactions among substitutions, which are much more difficult to predict. Even fewer do this comprehensively for a catalytic function. To provide a testbed for evaluating predictive models for enzyme engineering, we constructed and analyzed a 160,000-member enzyme sequence-fitness dataset at four interacting residues near the active site of tryptophan synthase, capturing significant non-additive effects of substitutions on catalytic function. It is necessary to predict and understand such interactions in order to efficiently traverse evolutionary landscapes and build machine learning models that accelerate protein engineering.
]]></description>
<dc:creator>Johnston, K. E.</dc:creator>
<dc:creator>Almhjell, P. J.</dc:creator>
<dc:creator>Watkins-Dulaney, E. J.</dc:creator>
<dc:creator>Liu, G.</dc:creator>
<dc:creator>Porter, N. J.</dc:creator>
<dc:creator>Yang, J.</dc:creator>
<dc:creator>Arnold, F. H.</dc:creator>
<dc:date>2024-06-26</dc:date>
<dc:identifier>doi:10.1101/2024.06.23.600144</dc:identifier>
<dc:title><![CDATA[A combinatorially complete epistatic fitness landscape in an enzyme active site]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-06-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.06.28.600796v1?rss=1">
<title>
<![CDATA[
Functional ultrasound neuroimaging reveals mesoscopic organization of saccades in the lateral intraparietal area of posterior parietal cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.06.28.600796v1?rss=1</link>
<description><![CDATA[
The lateral intraparietal cortex (LIP) located within the posterior parietal cortex (PPC) is an important area for the transformation of spatial information into accurate saccadic eye movements. Despite extensive research, we do not fully understand the functional anatomy of intended movement directions within LIP. This is in part due to technical challenges. Electrophysiology recordings can only record from small regions of the PPC, while fMRI and other whole-brain techniques lack sufficient spatiotemporal resolution. Here, we use functional ultrasound imaging (fUSI), an emerging technique with high sensitivity, large spatial coverage, and good spatial resolution, to determine how movement direction is encoded across PPC. We used fUSI to record local changes in cerebral blood volume in PPC as two monkeys performed memory-guided saccades to targets throughout their visual field. We then analyzed the distribution of preferred directional response fields within each coronal plane of PPC. Many subregions within LIP demonstrated strong directional tuning that was consistent across several months to years. These mesoscopic maps revealed a highly heterogenous organization within LIP with many small patches of neighboring cortex encoding different directions. LIP had a rough topography where anterior LIP represented more contralateral upward movements and posterior LIP represented more contralateral downward movements. These results address two fundamental gaps in our understanding of LIPs functional organization: the neighborhood organization of patches and the broader organization across LIP. These findings were achieved by tracking the same LIP populations across many months to years and developing mesoscopic maps of direction specificity previously unattainable with fMRI or electrophysiology methods.
]]></description>
<dc:creator>Griggs, W. S.</dc:creator>
<dc:creator>Norman, S. L.</dc:creator>
<dc:creator>Tanter, M.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Christopoulos, V.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2024-07-02</dc:date>
<dc:identifier>doi:10.1101/2024.06.28.600796</dc:identifier>
<dc:title><![CDATA[Functional ultrasound neuroimaging reveals mesoscopic organization of saccades in the lateral intraparietal area of posterior parietal cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.04.602005v1?rss=1">
<title>
<![CDATA[
Time-resolved functional connectivity during visuomotor graph learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.04.602005v1?rss=1</link>
<description><![CDATA[
1Humans naturally attend to patterns that emerge in our perceptual environments, building mental models that allow future experiences to be processed more effectively and efficiently. Perceptual events and statistical relations can be represented as nodes and edges in a graph. Recent work in graph learning has shown that human behavior is sensitive to graph topology, but little is known about how that topology might elicit distinct neural responses during learning. Here, we address this knowledge gap by applying time-resolved network analyses to fMRI data collected during a visuomotor graph learning task. We assess neural signatures of learning on two types of structures: modular and non-modular lattice graphs. We find that task performance is supported by a highly flexible visual system, relatively stable brain-wide community structure, cohesiveness within the dorsal attention, limbic, default mode, and subcortical systems, and an increasing degree of integration between the visual and ventral attention systems. Additionally, we find that the time-resolved connectivity of the limbic, default mode, temporoparietal, and subcortical systems is associated with enhanced performance on modular graphs but not on lattice-like graphs. These findings provide evidence for the differential processing of statistical patterns with distinct underlying graph topologies. Our work highlights the similarities between the neural correlates of graph learning and those of statistical learning.
]]></description>
<dc:creator>Loman, S.</dc:creator>
<dc:creator>Caciagli, L.</dc:creator>
<dc:creator>Kahn, A. E.</dc:creator>
<dc:creator>Szymula, K. P.</dc:creator>
<dc:creator>Nyema, N.</dc:creator>
<dc:creator>Bassett, D. S.</dc:creator>
<dc:date>2024-07-08</dc:date>
<dc:identifier>doi:10.1101/2024.07.04.602005</dc:identifier>
<dc:title><![CDATA[Time-resolved functional connectivity during visuomotor graph learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.05.601986v1?rss=1">
<title>
<![CDATA[
Wide-field bond-selective fluorescence imaging: from single-molecule to cellular imaging beyond video-rate 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.05.601986v1?rss=1</link>
<description><![CDATA[
Wide-field (WF) imaging is pivotal for observing dynamic biological events. While WF chemical microscopy offers high molecular specificity, it lacks the sensitivity for single-molecule detection. In contrast, WF fluorescence microscopy provides live-cell dynamic mapping but fails to leverage the rich chemical information necessary for functional interpretations. To address these limitations, we introduce Wide-Field Bond-selective Fluorescence-detected Infrared-Excited (WF-BonFIRE) spectro-microscopy. This technique combines rationally optimized imaging speed and field-of-view (FOV) to achieve single-molecule sensitivity with bond-selective contrast. WF-BonFIRE outperforms its point-scanning counterpart, enhancing frame acquisition up to 10,000 times. We demonstrate WF-BonFIREs capabilities in imaging cells, astrocytes, and live neurons, capturing single FOVs up to 50 {micro}m x 50 {micro}m, with further expansion via multi-FOV mosaicking. Additionally, we have implemented a temporal-delay modulation scheme that allows real-time kilohertz imaging speeds up to 1500 Hz. This enables millisecond temporal resolution while monitoring random motion of live Escherichia coli. Overall, WF-BonFIRE significantly broadens the possibilities for chemical imaging, enabling high-speed observations at unparalleled sensitivity levels.

One-Sentence SummaryWide-field bond-selective fluorescence imaging pushes chemical-sensitive microscopy platform into a new regime, achieving single-molecule sensitivity and speeds up to kilohertz.
]]></description>
<dc:creator>Lee, D.</dc:creator>
<dc:creator>Wang, H.</dc:creator>
<dc:creator>Kocheril, P. A.</dc:creator>
<dc:creator>Bi, X.</dc:creator>
<dc:creator>Naji, N.</dc:creator>
<dc:creator>Wei, L.</dc:creator>
<dc:date>2024-07-10</dc:date>
<dc:identifier>doi:10.1101/2024.07.05.601986</dc:identifier>
<dc:title><![CDATA[Wide-field bond-selective fluorescence imaging: from single-molecule to cellular imaging beyond video-rate]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.08.602577v1?rss=1">
<title>
<![CDATA[
Rapid evolution of gene expression patterns in flowering plants 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.08.602577v1?rss=1</link>
<description><![CDATA[
Phenotypic differences between species are largely driven by changes in both protein-coding sequence and gene expression 1. The evolutionary history of angiosperms (flowering plants) is characterised by a highly accelerated rate of diversification, which Darwin referred to as an "abominable mystery" 2. Here we show, by analysing the transcriptomes from eight organs across seven species, that angiosperm protein-coding gene expression patterns evolve rapidly: within 45 million years, expression levels of orthologous genes diverged so strongly that they are more similar between different organs within a species than between what are considered homologous organs from different species. This finding differs from previous observations in mammals, which demonstrated that organ-dependent gene expression levels are largely conserved 3, 4, 5. Among the angiosperm organs, meristems and leaves show the highest degree of expression conservation, whereas stamen and pollen transcriptomes diverge rapidly. Examining changes in the expression level of functionally related genes, we found low rates for those involved in key cellular, metabolic and developmental processes. In contrast, particularly high rates were observed for genes that are involved in the response to endogenous and external stimuli, presumably reflecting an adaptive response of flowering plants to ever-changing environments. Our work reveals that the evolution of gene expression progresses at different rates in angiosperms and mammals, and provides a comprehensive resource to perform cross-kingdom comparative studies of transcriptome evolution.
]]></description>
<dc:creator>Schuster, C.</dc:creator>
<dc:creator>Gabel, A.</dc:creator>
<dc:creator>Drost, H.-G.</dc:creator>
<dc:creator>Grosse, I.</dc:creator>
<dc:creator>Leyser, O.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:date>2024-07-10</dc:date>
<dc:identifier>doi:10.1101/2024.07.08.602577</dc:identifier>
<dc:title><![CDATA[Rapid evolution of gene expression patterns in flowering plants]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.13.603403v1?rss=1">
<title>
<![CDATA[
Estimating cis and trans contributions todifferences in gene regulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.13.603403v1?rss=1</link>
<description><![CDATA[
We describe a coordinate system and associated hypothesis testing framework for determining whether cis or trans regulation is responsible for differences in gene expression between two homozygous strains or species. We apply our framework to data from single replicate studies on yeast strains and human-chimpanzee hybrid cells, as well as to data from a mouse study with replicates, showing marked differences between our gene regulatory assignments and those previously reported. We also show how our multi-sample framework can determine the context dependency of cis and trans effects as well as explicitly model different hypotheses regarding the underlying mechanism of trans regulation.
]]></description>
<dc:creator>Hallgrimsdottir, I. B.</dc:creator>
<dc:creator>Carilli, M.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2024-07-16</dc:date>
<dc:identifier>doi:10.1101/2024.07.13.603403</dc:identifier>
<dc:title><![CDATA[Estimating cis and trans contributions todifferences in gene regulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.16.603764v1?rss=1">
<title>
<![CDATA[
Spatial evidence of cryptic methane cycling and methylotrophic metabolisms along a land-ocean transect in a California coastal wetland 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.16.603764v1?rss=1</link>
<description><![CDATA[
Methylotrophic methanogenesis in the sulfate reduction zone of coastal and marine sediments couples with anaerobic methane oxidation (AOM), forming the cryptic methane cycle. This study provides evidence of cryptic methane cycling in the sulfate-reducing zone across a land-ocean transect of four stations--two brackish, one marine, and one hypersaline--within the Carpinteria Salt Marsh Reserve (CSMR), Southern California, USA. The top 20 cm of sediment from the transect underwent geochemical and molecular (16S rRNA) analyses, in-vitro methanogenesis incubations, and radiotracer incubations using 35S-SO4, 14C-mono-methylamine, and 14C-CH4. Sediment methane concentrations were consistently low (3 to 28 {micro}M) except at the marine station, where they increased with depth (max 665 {micro}M). Methanogenesis from mono-methylamine was detected throughout the sediment at all stations with estimated rates ranging between 0.14 and 3.8 nmol cm-3 d-1. 16S rRNA analysis identified methanogenic archaea capable of producing methane from methylamines in sediment where methanogenesis was found to be active. Metabolomic analysis of porewater showed mono-methylamine was mostly undetectable (<3 {micro}M) or present in trace amounts (<10 {micro}M) suggesting rapid metabolic turnover. In-vitro methanogenesis incubations showed no linear methane buildup, suggesting a process limiting methane emissions. AOM activity, measured with 14C-CH4, overlapped with methanogenesis from mono-methylamine activity at all stations, with rates ranging from 0.03 to 19.4 nmol cm-3 d-1. Porewater geochemical analysis showed the CSMR sediments are rich in sulfate and iron. Porewater sulfate concentrations (9-91 mM) were non-limiting across the transect, which support members of sulfate-reducing bacteria and likely responsible for sulfate reduction activity (1.5-2,506 nmol cm-3 d-1) at all stations in the CSMR. Porewater sulfide and iron (II) profiles indicated that the sediment transitioned from a predominantly iron-reducing environment at the two brackish stations to a predominantly sulfate-reducing environment at the marine and hypersaline station. AOM activity was likely coupled to sulfate and possibly iron reduction, coinciding with the presence of anaerobic methanotrophs and bacteria involved in these reductions. 16S rRNA analysis identified anaerobic methanotrophs at the marine and hypersaline stations, where they coexisted with putative methanogens, suggesting both groups, or methanogens alone, may be involved in cryptic methane cycling, preventing significant methane buildup in the sulfate-reducing zone. Differences in rate constants from 14C radiotracer incubations suggest a non-methanogenic process oxidizing mono-methylamine to inorganic carbon, likely mediated by sulfate-reducing bacteria. Understanding the potential competition of sulfate reducers with methanogens for mono-methylamine needs further investigation as it might be another important process responsible for low methane emissions in salt marshes.
]]></description>
<dc:creator>Krause, S. J. E.</dc:creator>
<dc:creator>Wipfler, R. L.</dc:creator>
<dc:creator>Liu, J.</dc:creator>
<dc:creator>Yousavich, D. J.</dc:creator>
<dc:creator>Robinson, D.</dc:creator>
<dc:creator>Hoyt, D. W.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:creator>Treude, T.</dc:creator>
<dc:date>2024-07-16</dc:date>
<dc:identifier>doi:10.1101/2024.07.16.603764</dc:identifier>
<dc:title><![CDATA[Spatial evidence of cryptic methane cycling and methylotrophic metabolisms along a land-ocean transect in a California coastal wetland]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.16.603717v1?rss=1">
<title>
<![CDATA[
Neural dynamics underlying minute-timescale persistent behavior in the human brain 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.16.603717v1?rss=1</link>
<description><![CDATA[
The ability to pursue long-term goals relies on a representations of task context that can both be maintained over long periods of time and switched flexibly when goals change. Little is known about the neural substrate for such minute-scale maintenance of task sets. Utilizing recordings in neurosurgical patients, we examined how groups of neurons in the human medial frontal cortex and hippocampus represent task contexts. When cued explicitly, task context was encoded in both brain areas and changed rapidly at task boundaries. Hippocampus exhibited a temporally dynamic code with fast decorrelation over time, preventing cross-temporal generalization. Medial frontal cortex exhibited a static code that decorrelated slowly, allowing generalization across minutes of time. When task context needed to be inferred as a latent variable, hippocampus encoded task context with a static code. These findings reveal two possible regimes for encoding minute-scale task-context representations that were engaged differently based on task demands.
]]></description>
<dc:creator>Courellis, H.</dc:creator>
<dc:creator>Valiante, T. A.</dc:creator>
<dc:creator>Mamelak, A. N.</dc:creator>
<dc:creator>Adolphs, R.</dc:creator>
<dc:creator>Rutishauser, U.</dc:creator>
<dc:date>2024-07-19</dc:date>
<dc:identifier>doi:10.1101/2024.07.16.603717</dc:identifier>
<dc:title><![CDATA[Neural dynamics underlying minute-timescale persistent behavior in the human brain]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.19.604228v1?rss=1">
<title>
<![CDATA[
Adaptive Safety Coding in the Prefrontal Cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.19.604228v1?rss=1</link>
<description><![CDATA[
Pivotal to self-preservation is the ability to identify when we are safe and when we are in danger. Previous studies have focused on safety estimations based on the features of external threats and do not consider how the brain integrates other key factors, including estimates about our ability to protect ourselves. Here we examine the neural systems underlying the online dynamic encoding of safety. The current preregistered study used two novel tasks to test four facets of safety estimation: Safety Prediction, Meta-representation, Recognition, and Value Updating. We experimentally manipulated safety estimation changing both levels of external threats and self-protection. Data were collected in two independent samples (behavioral N=100; fMRI N=30). We found consistent evidence of subjective changes in the sensitivity to safety conferred through protection. Neural responses in the ventromedial prefrontal cortex (vmPFC) tracked increases in safety during all safety estimation facets, with specific tuning to protection. Further, informational connectivity analyses revealed distinct hubs of safety coding in the posterior and anterior vmPFC for external threats and protection, respectively. These findings reveal a central role of the vmPFC for coding safety.
]]></description>
<dc:creator>Tashjian, S. M.</dc:creator>
<dc:creator>Cussen, J.</dc:creator>
<dc:creator>Deng, W.</dc:creator>
<dc:creator>Zhang, B.</dc:creator>
<dc:creator>Mobbs, D.</dc:creator>
<dc:date>2024-07-23</dc:date>
<dc:identifier>doi:10.1101/2024.07.19.604228</dc:identifier>
<dc:title><![CDATA[Adaptive Safety Coding in the Prefrontal Cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.19.604332v1?rss=1">
<title>
<![CDATA[
Long-lived adult-born hippocampal neurons promote successful cognitive aging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.19.604332v1?rss=1</link>
<description><![CDATA[
Aging is commonly associated with a decline in memory abilities, yet some individuals remain resilient with preserved memory abilities. Memory processing is critically dependent on adult neurogenesis, a unique form of plasticity in the hippocampus. However, it remains unknown if cognitive aging influences the integration and role of adult-born hippocampal neurons (ABNs) generated early in adult life. Here, we investigated the role of long-lived ABNs in rats characterized as either resilient or vulnerable to cognitive aging using a peudo-longitudinal approach. Our findings reveal that long-lived ABNs support successful cognitive aging by preserving their synaptic inputs onto the proximal segments of their dendrites, and that these proximal synaptic sites also demonstrate a maintenance of their mitochondrial homeostasis. Furthermore, by-passing the reduced inputs of ABNs in vulnerable rats through direct optogenetic stimulation successfully improved their memory abilities. Overall, our data indicate that the maintenance of long-lived ABNs integration within the neuronal network is essential for successful cognitive aging, highlighting their potential as a therapeutic target for restoring cognitive functions in old age.

Graphical abstract

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]]></description>
<dc:creator>Blin, N.</dc:creator>
<dc:creator>Charrier, V.</dc:creator>
<dc:creator>Farrugia, F.</dc:creator>
<dc:creator>Cartier, E.</dc:creator>
<dc:creator>Pacary, E.</dc:creator>
<dc:creator>Koehl, M.</dc:creator>
<dc:creator>Lois, C.</dc:creator>
<dc:creator>Lie, D. C.</dc:creator>
<dc:creator>Masachs, N.</dc:creator>
<dc:creator>Abrous, N.</dc:creator>
<dc:date>2024-07-23</dc:date>
<dc:identifier>doi:10.1101/2024.07.19.604332</dc:identifier>
<dc:title><![CDATA[Long-lived adult-born hippocampal neurons promote successful cognitive aging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.26.605266v1?rss=1">
<title>
<![CDATA[
Asynchronous mouse embryo polarization leads to heterogeneity in cell fate specification 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.26.605266v1?rss=1</link>
<description><![CDATA[
The first lineage allocation in mouse and human embryos separates the inner cell mass (ICM) from the outer trophectoderm (TE). This symmetry breaking event is executed through polarization of cells at the 8-cell stage and subsequent asymmetric divisions, generating polar (TE) and apolar (ICM) cells. Here, we show that embryo polarization is unexpectedly asynchronous. Cells polarizing at the early and late 8-cell stage have distinct molecular and morphological properties that direct their following lineage specification, with early polarizing cells being biased towards producing the TE lineage. More recent studies have also implicated heterogeneities between cells prior to the 8-cell stage in the first lineage allocation: cells exhibiting reduced methyltransferase CARM1 activity at the 4-cell stage are predisposed towards the TE fate. Here, we demonstrate that reduced CARM1 activity and upregulation of its substrate BAF155 promote early polarization and TE specification. These findings provide a link between asymmetries at the 4-cell stage and polarization at the 8-cell stage, mechanisms of the first lineage allocation that had been considered separate.
]]></description>
<dc:creator>Lamba, A.</dc:creator>
<dc:creator>Zhu, M.</dc:creator>
<dc:creator>Meglicki, M.</dc:creator>
<dc:creator>Czukiewska, S.</dc:creator>
<dc:creator>Balasubramaniam, L.</dc:creator>
<dc:creator>Hadas, R.</dc:creator>
<dc:creator>Weishaupt, N.</dc:creator>
<dc:creator>Patel, E.</dc:creator>
<dc:creator>Kavanagh, Y. H.</dc:creator>
<dc:creator>Wang, R.</dc:creator>
<dc:creator>Jing, N.</dc:creator>
<dc:creator>Zernicka-Goetz, M.</dc:creator>
<dc:date>2024-07-26</dc:date>
<dc:identifier>doi:10.1101/2024.07.26.605266</dc:identifier>
<dc:title><![CDATA[Asynchronous mouse embryo polarization leads to heterogeneity in cell fate specification]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.27.605457v1?rss=1">
<title>
<![CDATA[
Active Learning-Assisted Directed Evolution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.27.605457v1?rss=1</link>
<description><![CDATA[
Directed evolution (DE) is a powerful tool to optimize protein fitness for a specific application. However, DE can be inefficient when mutations exhibit non-additive, or epistatic, behavior. Here, we present Active Learning-assisted Directed Evolution (ALDE), an iterative machine learning-assisted DE workflow that leverages uncertainty quantification to explore the search space of proteins more efficiently than current DE methods. We apply ALDE to an engineering landscape that is challenging for DE: optimization of five epistatic residues in the active site of an enzyme. In three rounds of wet-lab experimentation, we improve the yield of a desired product of a non-native cyclopropanation reaction from 12% to 93%. We also perform computational simulations on existing protein sequence-fitness datasets to support our argument that ALDE can be more effective than DE. Overall, ALDE is a practical and broadly applicable strategy to unlock improved protein engineering outcomes.
]]></description>
<dc:creator>Yang, J.</dc:creator>
<dc:creator>Lal, R. G.</dc:creator>
<dc:creator>Bowden, J. C.</dc:creator>
<dc:creator>Astudillo, R.</dc:creator>
<dc:creator>Hameedi, M. A.</dc:creator>
<dc:creator>Kaur, S.</dc:creator>
<dc:creator>Hill, M.</dc:creator>
<dc:creator>Yue, Y.</dc:creator>
<dc:creator>Arnold, F. H.</dc:creator>
<dc:date>2024-07-28</dc:date>
<dc:identifier>doi:10.1101/2024.07.27.605457</dc:identifier>
<dc:title><![CDATA[Active Learning-Assisted Directed Evolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.31.605825v1?rss=1">
<title>
<![CDATA[
Nonlinear sound-sheet microscopy: imaging opaque organs at the capillary and cellular scale 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.31.605825v1?rss=1</link>
<description><![CDATA[
Light-sheet fluorescence microscopy has revolutionized biology by visualizing dynamic cellular processes in three dimensions. However, light scattering in thick tissue and photobleaching of fluorescent reporters limit this method to studying thin or translucent specimens. Here we show that non-diffractive ultrasonic beams used in conjunction with a cross-amplitude modulation sequence and nonlinear acoustic reporters enable fast and volumetric imaging of targeted biological functions. We report volumetric imaging of tumor gene expression at the cm3 scale using genetically encoded gas vesicles, and localization microscopy of currently uncharted cerebral capillary networks using intravascular microbubble contrast agents. Nonlinear sound-sheet microscopy provides a [~]64x acceleration in imaging speed, [~]35x increase in imaged volume and [~]4x increase in classical imaging resolution compared to the state-of-the-art in biomolecular ultrasound.
]]></description>
<dc:creator>Heiles, B.</dc:creator>
<dc:creator>Nelissen, F.</dc:creator>
<dc:creator>Terwiel, D.</dc:creator>
<dc:creator>Park, B. M.</dc:creator>
<dc:creator>Munoz Ibarra, E.</dc:creator>
<dc:creator>Matalliotakis, A.</dc:creator>
<dc:creator>Waasdorp, R.</dc:creator>
<dc:creator>Ara, T.</dc:creator>
<dc:creator>Barturen-Larrea, P.</dc:creator>
<dc:creator>Duan, M.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Gazzola, V.</dc:creator>
<dc:creator>Maresca, D.</dc:creator>
<dc:date>2024-07-31</dc:date>
<dc:identifier>doi:10.1101/2024.07.31.605825</dc:identifier>
<dc:title><![CDATA[Nonlinear sound-sheet microscopy: imaging opaque organs at the capillary and cellular scale]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.07.31.605918v1?rss=1">
<title>
<![CDATA[
Neutralizing antibodies elicited in sequentially immunized macaques recognize V3 residues on altered conformations of HIV-1 Env trimer 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.07.31.605918v1?rss=1</link>
<description><![CDATA[
Eliciting broadly neutralizing antibodies that protect against diverse HIV-1 strains is a primary goal of AIDS vaccine research. We characterized Ab1456 and Ab1271, two heterologously-neutralizing antibodies elicited in non-human primates by priming with an engineered V3-targeting SOSIP Env immunogen and boosting with increasingly native-like SOSIP Envs derived from different strain backgrounds. Structures of Env trimers in complex with these antibodies revealed V3 targeting, but on conformational states of Env distinct from the typical closed, prefusion trimeric SOSIP structure. Env trimers bound by Ab1456 adopted conformations resembling CD4-bound open Env states in the absence of soluble CD4, whereas trimers bound by Ab1271 exhibited a trimer apex-altered conformation to accommodate antibody binding. The finding that elicited antibodies cross-neutralized by targeting altered, non-closed, prefusion Env trimer conformations provides important information about Env dynamics that is relevant for HIV-1 vaccine design aimed at raising antibodies to desired epitopes on closed pre-fusion Env trimers.

Highlights- Sequential immunization regimen elicits V3 antibodies targeting non-closed Envs
- Cryo-EM structures reveal recognition of multiple Env conformational states
- Neutralization by elicited antibody does not require antibody-virus preincubation


Graphical Abstract

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]]></description>
<dc:creator>DeLaitsch, A. T.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>Lee, J. A.</dc:creator>
<dc:creator>Ding, W.</dc:creator>
<dc:creator>Liu, W.</dc:creator>
<dc:creator>Skelly, A. N.</dc:creator>
<dc:creator>Shaw, G. M.</dc:creator>
<dc:creator>Hahn, B. H.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2024-08-01</dc:date>
<dc:identifier>doi:10.1101/2024.07.31.605918</dc:identifier>
<dc:title><![CDATA[Neutralizing antibodies elicited in sequentially immunized macaques recognize V3 residues on altered conformations of HIV-1 Env trimer]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-08-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.08.01.606171v1?rss=1">
<title>
<![CDATA[
Root traits and tree functional groups determine variability in root exudation and N uptake rates in mature temperate trees 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.08.01.606171v1?rss=1</link>
<description><![CDATA[
While root exudation has the potential to affect soil biogeochemistry profoundly, the process is rarely quantified in mature, field-grown trees. We measured rates of carbon (C) exudation in 11 trees species that exhibit divergent root traits, including gymnosperms and angiosperms that associate with either arbuscular mycorrhizal (AM) or ectomycorrhizal (EcM) fungi. Our goal was to explore how tree species, plant functional groups and root traits collectively influence exudation patterns. Intraspecific variation in exudation rates was larger than interspecific variation, and neither functional groups nor morphological traits alone could sufficiently explain variation in this flux. EcM-associated gymnosperms exuded 2.4 times more C than EcM angiosperms and 1.5 times more than AM gymnosperms. Exudation rates correlated positively with specific root length (SRL) and specific root area (SRA), and were correlated with root tissue density and root diameter in EcM-associated species. Mixed-effect models revealed that exudation rates were best determined by a combination of phylogenetic group, tree-mycorrhizal type and SRA, though a large portion of unexplained variation suggests that contemporary environmental and local edaphic conditions are likely important. Collectively, our results reveal that exudation is a complex physiological process governed by multiple factors and cannot be fully explained by functional groups or root traits alone. Instead, a combined consideration of these factors and new experimental approaches may be needed before exudation patterns can be linked to plant trait frameworks and incorporated into large-scale models.
]]></description>
<dc:creator>Oh, Y. E.</dc:creator>
<dc:creator>Midgley, M. G.</dc:creator>
<dc:creator>McCormack, M. L.</dc:creator>
<dc:creator>Beidler, K. V.</dc:creator>
<dc:creator>McCall, M.</dc:creator>
<dc:creator>Henderson, S.</dc:creator>
<dc:creator>Braghiere, R. K.</dc:creator>
<dc:creator>Phillips, R. P.</dc:creator>
<dc:date>2024-08-04</dc:date>
<dc:identifier>doi:10.1101/2024.08.01.606171</dc:identifier>
<dc:title><![CDATA[Root traits and tree functional groups determine variability in root exudation and N uptake rates in mature temperate trees]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-08-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.08.19.608557v1?rss=1">
<title>
<![CDATA[
Electron tomography visualization of HIV-1 virions trapped by fusion inhibitors to host cells in infected tissues 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.08.19.608557v1?rss=1</link>
<description><![CDATA[
HIV-1 delivers its genetic material to infect a cell after fusion of the viral and host cell membranes, which takes place after the viral envelope (Env) binds host receptor and co-receptor proteins. Binding of host receptor CD4 to Env results in conformational changes that allow interaction with a host co-receptor (CCR5 or CXCR4). Further conformational rearrangements result in an elongated pre-hairpin intermediate structure in which Env is anchored to the viral membrane by its transmembrane region and to the host cell membrane by its fusion peptide. Although budding virions can be readily imaged by electron tomography (ET) of HIV-1-infected tissues and cultured cells, virions that are fusing (attached to host cells via pre-hairpin intermediates) are not normally visualized, perhaps because the process of membrane fusion is too fast to capture by EM. To image virions during fusion, we used fusion inhibitors to prevent downstream conformational changes in Env that lead to membrane fusion, thereby trapping HIV-1 virions linked to target cells by prehairpin intermediates. ET of HIV-1 pseudovirions bound to CD4+/CCR5+ TZM-bl cells revealed presumptive pre-hairpin intermediates as 2-4 narrow spokes linking a virion to the cell surface. To extend these results to a more physiological setting, we used ET to image tissues and organs derived from humanized bone marrow, liver, thymus (BLT) mice infected with HIV-1 and then treated with CPT31, a high-affinity D-peptide fusion inhibitor linked to cholesterol. Trapped HIV-1 virions were found in all tissues studied (small intestine, mesenteric lymph nodes, spleen, and bone marrow), and spokes representing pre-hairpin intermediates linking trapped virions to cell surfaces were similar in structure and number to those seen in the previous pseudovirus and cultured cell ET study.

IMPORTANCETrapped and untrapped HIV-1 virions, both mature and immature, were distinguished by localizing spokes via 3D tomographic reconstructions of HIV-1 infected and fusion-inhibitor treated tissues of humanized mice. The finding of trapped HIV-1 virions in all tissues examined demonstrates a wide distribution of the CPT31 inhibitor, a desirable property for a potential therapeutic. In addition, the presence of virions trapped by spokes, particularly in vascular endothelial cells, demonstrates that fusion inhibitors can be used as markers for potential HIV-1-target cells within tissues, facilitating the mapping of HIV-1 target cells within the complex cellular milieu of infected tissues.
]]></description>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Zhu, L.</dc:creator>
<dc:creator>Ullah, I.</dc:creator>
<dc:creator>Uchil, P. D.</dc:creator>
<dc:creator>Kumar, P.</dc:creator>
<dc:creator>Kay, M. S.</dc:creator>
<dc:date>2024-08-19</dc:date>
<dc:identifier>doi:10.1101/2024.08.19.608557</dc:identifier>
<dc:title><![CDATA[Electron tomography visualization of HIV-1 virions trapped by fusion inhibitors to host cells in infected tissues]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-08-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.08.20.608861v1?rss=1">
<title>
<![CDATA[
Motor-driven microtubule diffusion in a photobleached dynamical coordinate system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.08.20.608861v1?rss=1</link>
<description><![CDATA[
Motor-driven cytoskeletal remodeling in cellular systems can often be accompanied by a diffusive-like effect at local scales, but distinguishing the contributions of the ordering process, such as active contraction of a network, from this active diffusion is difficult to achieve. Using light-dimerizable kinesin motors to spatially control the formation and contraction of a microtubule network, we deliberately photobleach a grid pattern onto the filament network serving as a transient and dynamic coordinate system to observe the deformation and translation of the remaining fluorescent squares of microtubules. We find that the network contracts at a rate set by motor speed but is accompanied by a diffusive-like spread throughout the bulk of the contracting network with effective diffusion constant two orders of magnitude lower than that for a freely-diffusing microtubule. We further find that on micron scales, the diffusive timescale is only a factor of {approx} 3 slower than that of advection regardless of conditions, showing that the global contraction and long-time relaxation from this diffusive behavior are both motor-driven but exhibit local competition within the network bulk.

O_TEXTBOXSignificance StatementCytoskeletal reorganization can come at the cost of local diffusive-like disordering effects from the same active elements, but distinguishing these processes can be challenging. By photobleaching an actively contracting microtubule network, we show that the bulk redistribution of filaments exhibit a diffusion-like reorganization that can be tuned by the effective motor speed. By tuning these parameters, we show a conserved relationship between active contraction rates and effective diffusion constants, suggesting that while advection of the cytoskeletal network dominates over scales of tens to hundreds of microns, motors additionally induce a diffusive-like effect that begins to compete with advection at micron scales.

C_TEXTBOX
]]></description>
<dc:creator>Hirokawa, S.</dc:creator>
<dc:creator>Lee, H. J.</dc:creator>
<dc:creator>Banks, R. A.</dc:creator>
<dc:creator>Duarte, A. I.</dc:creator>
<dc:creator>Najma, B.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2024-08-20</dc:date>
<dc:identifier>doi:10.1101/2024.08.20.608861</dc:identifier>
<dc:title><![CDATA[Motor-driven microtubule diffusion in a photobleached dynamical coordinate system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-08-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.08.20.608874v1?rss=1">
<title>
<![CDATA[
Quantifying microbial fitness in high-throughput experiments 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.08.20.608874v1?rss=1</link>
<description><![CDATA[
Few concepts are as central to evolution as is fitness, and yet the quantification of fitness is often ambiguous. In particular, high-throughput experiments to measure mutant fitness in microbes are increasingly common but vary widely in their definitions of fitness, which makes their results difficult to compare. What are the consequences of these different fitness statistics, and is there a best way to quantify fitness in a given context? Here we systematize the set of possible fitness statistics according to the following three choices: 1) the encoding of relative abundance (e.g., transforming by a log or logit function), 2) the time scale over which to measure the change in relative abundance, and 3) the choice of a reference subpopulation for calculating relative fitness in bulk competition experiments, such as those using DNA-barcoded mutants. We show that these different choices can lead to significantly different interpretations of mutant fitness, affecting the magnitude of fitness effects, the apparent presence of epistasis, and even the fitness ranking across mutants. This can confound predictions for evolutionary dynamics and gene functions. Altogether our results demonstrate the importance of consistent fitness definitions for reproducible results across experiments.
]]></description>
<dc:creator>Fink, J. W.</dc:creator>
<dc:creator>Manhart, M.</dc:creator>
<dc:date>2024-08-20</dc:date>
<dc:identifier>doi:10.1101/2024.08.20.608874</dc:identifier>
<dc:title><![CDATA[Quantifying microbial fitness in high-throughput experiments]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-08-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.08.25.609544v1?rss=1">
<title>
<![CDATA[
Cellular and molecular networks of intercellular signaling in bone marrow hematopoiesis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.08.25.609544v1?rss=1</link>
<description><![CDATA[
Hematopoietic stem and progenitor cells (HSPCs) rely on intercellular signaling to maintain and adjust their production of blood and immune cells. This process occurs in the semi-fluidic bone marrow, hosting dozens of cell types that constantly migrate and interact. To elucidate the dynamic network of cell-cell interaction and signaling transduction underlying hematopoiesis, we developed an algorithm to measure Cell-cell Spatial Interaction Probability (CellSIP) by integrating data on ligand and receptor expression, cell type abundance, and cellular spatial positioning. Using new and published mouse datasets, we validated CellSIP and uncovered signaling transductions indicating feedback mechanisms underlying hematopoiesis. Moreover, we identified significant correlations between signaling pathways across individual HSPCs at the same hematopoiesis stage. These pathway correlations illuminate the organization of cellular and signaling networks underlying hematopoiesis, revealing new regulators through their associations with established ones. The signaling quantification and correlation data are available through the Hematopoiesis Intercellular Signaling Explorer (HISE).
]]></description>
<dc:creator>Thomas, Z.</dc:creator>
<dc:creator>Wang, B.</dc:creator>
<dc:creator>Boohar, W.</dc:creator>
<dc:creator>Vergel, M.</dc:creator>
<dc:creator>Eerdeng, J.</dc:creator>
<dc:creator>Shon, D.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:creator>Lu, R.</dc:creator>
<dc:date>2024-08-26</dc:date>
<dc:identifier>doi:10.1101/2024.08.25.609544</dc:identifier>
<dc:title><![CDATA[Cellular and molecular networks of intercellular signaling in bone marrow hematopoiesis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-08-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.08.28.610193v1?rss=1">
<title>
<![CDATA[
Brain Charts for the Rhesus Macaque Lifespan 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.08.28.610193v1?rss=1</link>
<description><![CDATA[
Recent efforts to chart human brain growth across the lifespan using large-scale MRI data have provided reference standards for human brain development. However, similar models for nonhuman primate (NHP) growth are lacking. The rhesus macaque, a widely used NHP in translational neuroscience due to its similarities in brain anatomy, phylogenetics, cognitive, and social behaviors to humans, serves as an ideal NHP model. This study aimed to create normative growth charts for brain structure across the macaque lifespan, enhancing our understanding of neurodevelopment and aging, and facilitating cross-species translational research. Leveraging data from the PRIMatE Data Exchange (PRIME-DE) and other sources, we aggregated 1,522 MRI scans from 1,024 rhesus macaques. We mapped non-linear developmental trajectories for global and regional brain structural changes in volume, cortical thickness, and surface area over the lifespan. Our findings provided normative charts with centile scores for macaque brain structures and revealed key developmental milestones from prenatal stages to aging, highlighting both species-specific and comparable brain maturation patterns between macaques and humans. The charts offer a valuable resource for future NHP studies, particularly those with small sample sizes. Furthermore, the interactive open resource (https://interspeciesmap.childmind.org) supports cross-species comparisons to advance translational neuroscience research.
]]></description>
<dc:creator>Alldritt, S.</dc:creator>
<dc:creator>Ramirez, J. S. B.</dc:creator>
<dc:creator>Vos de Wael, R.</dc:creator>
<dc:creator>Bethlehem, R.</dc:creator>
<dc:creator>Seidlitz, J.</dc:creator>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>Nenning, K.-H.</dc:creator>
<dc:creator>Esper, N. B.</dc:creator>
<dc:creator>Smallwood, J.</dc:creator>
<dc:creator>Franco, A. R.</dc:creator>
<dc:creator>Byeon, K.</dc:creator>
<dc:creator>Alexander-Bloch, A.</dc:creator>
<dc:creator>Messinger, A.</dc:creator>
<dc:creator>Chen, A.</dc:creator>
<dc:creator>Thiele, A.</dc:creator>
<dc:creator>Weiss, A. R.</dc:creator>
<dc:creator>Shmuel, A.</dc:creator>
<dc:creator>Fox, A.</dc:creator>
<dc:creator>Tusche, A.</dc:creator>
<dc:creator>Brambrink, A. M.</dc:creator>
<dc:creator>Falchier, A.</dc:creator>
<dc:creator>Hiba, B.</dc:creator>
<dc:creator>Jarraya, B.</dc:creator>
<dc:creator>Jung, B.</dc:creator>
<dc:creator>Butler, B.</dc:creator>
<dc:creator>Russ, B. E.</dc:creator>
<dc:creator>Howell, B. R.</dc:creator>
<dc:creator>Drzewiecki, C. M.</dc:creator>
<dc:creator>Guedj, C.</dc:creator>
<dc:creator>Schwiedrzik, C. M.</dc:creator>
<dc:creator>Amiez, C.</dc:creator>
<dc:creator>Wilson, C. R. E.</dc:creator>
<dc:creator>Klink, C.</dc:creator>
<dc:creator>Kroenke, C.</dc:creator>
<dc:creator>Constantinidis, C.</dc:creator>
<dc:creator>Garin, C. M.</dc:creator>
<dc:creator>Poirier, C.</dc:creator>
<dc:creator>Gale, D. J.</dc:creator>
<dc:creator>Leopold, D. A.</dc:creator>
<dc:creator>Rudko, D. A.</dc:creator>
<dc:creator>Amaral, D. G.</dc:creator>
<dc:creator>Tsao, D.</dc:creator>
<dc:creator>Cook, D. J.</dc:creator>
<dc:creator></dc:creator>
<dc:date>2024-08-30</dc:date>
<dc:identifier>doi:10.1101/2024.08.28.610193</dc:identifier>
<dc:title><![CDATA[Brain Charts for the Rhesus Macaque Lifespan]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-08-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.09.02.610758v1?rss=1">
<title>
<![CDATA[
Benchmarking Protein Language Models for Protein Crystallization 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.09.02.610758v1?rss=1</link>
<description><![CDATA[
The problem of protein structure determination is usually solved by X-ray crystallography. Several in silico deep learning methods have been developed to overcome the high attrition rate, cost of experiments and extensive trial-and-error settings, for the predicting the crystallization propensities of proteins based on their sequences. In this work, we benchmark the power of open protein language models (PLMs) through the TRILL platform, a bespoke framework democratizing the usage of PLMs for the task of predicting crystallization propensities of proteins.

By comparing LightGBM / XGBoost classifiers built on the embedding representations learned by different PLMs, such as ESM2, Ankh, ProtT5-XL, ProstT5, with the performance of state-of-the-art sequence-based methods like DeepCrystal, ATTCrys and CLPred, we identify the most effective methods for predicting crystallization outcomes. The LightGBM classifiers utilizing embeddings from ESM2 model with 30 and 36 transformer layers and 150 and 3, 000 million parameters respectively have performance gains by 3 - 5% then all compared models for various evaluation metrics, including AUPR (Area Under Precision-Recall Curve), AUC (Area Under the Receiver Operating Characteristic Curve), and F1 score on independent test sets.

Furthermore, we fine-tune the ProtGPT2 model available via TRILL to generate crystallizable proteins. Starting with 3, 000 generated proteins and through a step of filtration processes including consensus of all open PLM-based classifiers, sequence identity through CD-HIT, secondary structure compatibility, aggregation screening, homology search and foldability evaluation, we identified a set of 5 novel proteins as potentially crystallizable.
]]></description>
<dc:creator>Mall, R.</dc:creator>
<dc:creator>Kaushik, R.</dc:creator>
<dc:creator>Martinez, Z. A.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Castiglione, F.</dc:creator>
<dc:date>2024-09-03</dc:date>
<dc:identifier>doi:10.1101/2024.09.02.610758</dc:identifier>
<dc:title><![CDATA[Benchmarking Protein Language Models for Protein Crystallization]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-09-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.09.04.611255v1?rss=1">
<title>
<![CDATA[
LevSeq: Rapid Generation of Sequence-Function Data for Directed Evolution and Machine Learning 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.09.04.611255v1?rss=1</link>
<description><![CDATA[
Sequence-function data provides valuable information about the protein functional landscape, but is rarely obtained during directed evolution campaigns. Here, we present Long-read every variant Sequencing (LevSeq), a pipeline that combines a dual barcoding strategy with nanopore sequencing to rapidly generate sequence-function data for entire protein-coding genes. LevSeq integrates into existing protein engineering workflows and comes with open-source software for data analysis and visualization. The pipeline facilitates data-driven protein engineering by consolidating sequence-function data to inform directed evolution and provide the requisite data for machine learning-guided protein engineering (MLPE). LevSeq enables quality control of mutagenesis libraries prior to screening, which reduces time and resource costs. Simulation studies demonstrate LevSeqs ability to accurately detect variants under various experimental conditions. Finally, we show LevSeqs utility in engineering protoglobins for new-to-nature chemistry. Widespread adoption of LevSeq and sharing of the data will enhance our understanding of protein sequence-function landscapes and empower data-driven directed evolution.
]]></description>
<dc:creator>Long, Y.</dc:creator>
<dc:creator>Mora, A.</dc:creator>
<dc:creator>Guersoy, E.</dc:creator>
<dc:creator>Johnston, K. E.</dc:creator>
<dc:creator>Li, F.-Z.</dc:creator>
<dc:creator>Arnold, F. H.</dc:creator>
<dc:date>2024-09-04</dc:date>
<dc:identifier>doi:10.1101/2024.09.04.611255</dc:identifier>
<dc:title><![CDATA[LevSeq: Rapid Generation of Sequence-Function Data for Directed Evolution and Machine Learning]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-09-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.09.12.612739v1?rss=1">
<title>
<![CDATA[
Human NLRP3 inflammasome activation leads to formation of condensate at the microtubule organizing center 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.09.12.612739v1?rss=1</link>
<description><![CDATA[
The NLRP3 inflammasome is a multi-protein molecular machine that mediates inflammatory responses in innate immunity. Its dysregulation has been linked to a large number of human diseases. Using cryogenic fluorescence-guided focused-ion-beam (cryo-FIB) milling and electron cryo-tomography (cryo-ET), we obtained 3-D images of the NLRP3 inflammasome in situ at various stages of its activation at macromolecular resolution. The cryo-tomograms unexpectedly reveal dense condensates of the human macrophage NLRP3 inflammasome that form within and around the microtubule organizing center (MTOC). We also find that following activation, the trans-Golgi network disperses and 50-nm NLRP3-associated vesicles appear which likely ferry NLRP3 to the MTOC. At later time points after activation, the electron-dense condensates progressively solidify and the cells undergo pyroptosis with widespread damaged mitochondria and autophagasomal structures.
]]></description>
<dc:creator>Wang, J.</dc:creator>
<dc:creator>Wu, M.</dc:creator>
<dc:creator>Magupalli, V.</dc:creator>
<dc:creator>Dahlberg, P.</dc:creator>
<dc:creator>Wu, H.</dc:creator>
<dc:creator>Jensen, G.</dc:creator>
<dc:date>2024-09-15</dc:date>
<dc:identifier>doi:10.1101/2024.09.12.612739</dc:identifier>
<dc:title><![CDATA[Human NLRP3 inflammasome activation leads to formation of condensate at the microtubule organizing center]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-09-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.09.17.613111v1?rss=1">
<title>
<![CDATA[
An integrated view of the structure and function of the human 4D nucleome 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.09.17.613111v1?rss=1</link>
<description><![CDATA[
The dynamic three-dimensional (3D) organization of the human genome (the "4D Nucleome") is closely linked to genome function. Here, we integrate a wide variety of genomic data generated by the 4D Nucleome Project to provide a detailed view of human 3D genome organization in widely used embryonic stem cells (H1-hESCs) and immortalized fibroblasts (HFFc6). We provide extensive benchmarking of 3D genome mapping assays and integrate these diverse datasets to annotate spatial genomic features across scales. The data reveal a rich complexity of chromatin domains and their sub-nuclear positions, and over one hundred thousand structural loops and promoter-enhancer interactions. We developed 3D models of population-based and individual cell-to-cell variation in genome structure, establishing connections between chromosome folding, nuclear organization, chromatin looping, gene transcription, and DNA replication. We demonstrate the use of computational methods to predict genome folding from DNA sequence, uncovering potential effects of genetic variants on genome structure and function. Together, this comprehensive analysis contributes insights into human genome organization and enhances our understanding of connections between the regulation of genome function and 3D genome organization in general.
]]></description>
<dc:creator>The 4D Nucleome Consortium,</dc:creator>
<dc:creator>Dekker, J.</dc:creator>
<dc:creator>Oksuz, B. A.</dc:creator>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Minsk, M. K.</dc:creator>
<dc:creator>Kuang, S.</dc:creator>
<dc:creator>Yang, L.</dc:creator>
<dc:creator>Gibcus, J. H.</dc:creator>
<dc:creator>Krietenstein, N.</dc:creator>
<dc:creator>Rando, O.</dc:creator>
<dc:creator>Xu, J.</dc:creator>
<dc:creator>Janssens, D. H.</dc:creator>
<dc:creator>Henikoff, S.</dc:creator>
<dc:creator>Kukalev, A.</dc:creator>
<dc:creator>Willemin, A.</dc:creator>
<dc:creator>Winick-Ng, W.</dc:creator>
<dc:creator>Kempfer, R.</dc:creator>
<dc:creator>Pombo, A.</dc:creator>
<dc:creator>Yu, M.</dc:creator>
<dc:creator>Kumar, P.</dc:creator>
<dc:creator>Zhang, L.</dc:creator>
<dc:creator>Belmont, A. S.</dc:creator>
<dc:creator>Sasaki, T.</dc:creator>
<dc:creator>van Schaik, T.</dc:creator>
<dc:creator>Brueckner, L.</dc:creator>
<dc:creator>Peric-Hupkes, D.</dc:creator>
<dc:creator>van Steensel, B.</dc:creator>
<dc:creator>Wang, P.</dc:creator>
<dc:creator>Chai, H.</dc:creator>
<dc:creator>Kim, M.</dc:creator>
<dc:creator>Ruan, Y.</dc:creator>
<dc:creator>Zhang, R.</dc:creator>
<dc:creator>Quinodoz, S. A.</dc:creator>
<dc:creator>Bhat, P.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:creator>Zhao, W.</dc:creator>
<dc:creator>Chien, S.</dc:creator>
<dc:creator>Liu, Y.</dc:creator>
<dc:creator>Venev, S. V.</dc:creator>
<dc:creator>Plewczynski, D.</dc:creator>
<dc:creator>Irastorza Azcarate, I.</dc:creator>
<dc:creator>Szabo, D.</dc:creator>
<dc:creator>Thieme, C. J.</dc:creator>
<dc:creator>Szczepinska,</dc:creator>
<dc:date>2024-09-19</dc:date>
<dc:identifier>doi:10.1101/2024.09.17.613111</dc:identifier>
<dc:title><![CDATA[An integrated view of the structure and function of the human 4D nucleome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-09-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.09.19.613934v1?rss=1">
<title>
<![CDATA[
Organ-specific Sympathetic Innervation Defines Visceral Functions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.09.19.613934v1?rss=1</link>
<description><![CDATA[
The autonomic nervous system orchestrates the brain and body functions through the sympathetic and parasympathetic pathways. However, our understanding of the autonomic system, especially the sympathetic system, at the cellular and molecular levels is severely limited. Here, we show unique topological representations of individual visceral organs in the major abdominal sympathetic ganglion complex. Using multi-modal transcriptomic analyses, we identified distinct sympathetic populations that are both molecularly and spatially separable in the celiac-superior mesenteric ganglia (CG-SMG). Notably, individual CG-SMG populations exhibit selective and mutually exclusive axonal projections to visceral organs, targeting either the gastrointestinal (GI) tract or secretory areas including the pancreas and bile tract. This combinatorial innervation pattern suggests functional segregation between different CG-SMG populations. Indeed, our neural perturbation experiments demonstrated that one class of neurons selectively regulates GI food transit. Another class of neurons controls digestion and glucagon secretion independent of gut motility. These results reveal the molecularly diverse sympathetic system and suggest modular regulations of visceral organ functions through distinct sympathetic populations.
]]></description>
<dc:creator>Wang, T.</dc:creator>
<dc:creator>Teng, B.</dc:creator>
<dc:creator>Yao, D. R.</dc:creator>
<dc:creator>Gao, W.</dc:creator>
<dc:creator>Oka, Y.</dc:creator>
<dc:date>2024-09-20</dc:date>
<dc:identifier>doi:10.1101/2024.09.19.613934</dc:identifier>
<dc:title><![CDATA[Organ-specific Sympathetic Innervation Defines Visceral Functions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-09-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.09.18.613276v1?rss=1">
<title>
<![CDATA[
The Unified Phenotype Ontology (uPheno): A framework for cross-species integrative phenomics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.09.18.613276v1?rss=1</link>
<description><![CDATA[
Phenotypic data are critical for understanding biological mechanisms and consequences of genomic variation, and are pivotal for clinical use cases such as disease diagnostics and treatment development. For over a century, vast quantities of phenotype data have been collected in many different contexts covering a variety of organisms. The emerging field of phenomics focuses on integrating and interpreting these data to inform biological hypotheses.

A major impediment in phenomics is the wide range of distinct and disconnected approaches to recording the observable characteristics of an organism. Phenotype data are collected and curated using free text, single terms or combinations of terms, using multiple vocabularies, terminologies, or ontologies. Integrating these heterogeneous and often siloed data enables the application of biological knowledge both within and across species. Existing integration efforts are typically limited to mappings between pairs of terminologies; a generic knowledge representation that captures the full range of cross-species phenomics data is much needed.

We have developed the Unified Phenotype Ontology (uPheno) framework, a community effort to provide an integration layer over domain-specific phenotype ontologies, as a single, unified, logical representation. uPheno comprises (1) a system for consistent computational definition of phenotype terms using ontology design patterns, maintained as a community library; (2) a hierarchical vocabulary of species-neutral phenotype terms under which their species-specific counterparts are grouped; and (3) mapping tables between species-specific ontologies. This harmonized representation supports use cases such as cross-species integration of genotype-phenotype associations from different organisms and cross-species informed variant prioritization.
]]></description>
<dc:creator>Matentzoglu, N.</dc:creator>
<dc:creator>Bello, S. M.</dc:creator>
<dc:creator>Stefancsik, R.</dc:creator>
<dc:creator>Alghamdi, S. M.</dc:creator>
<dc:creator>Anagnostopoulos, A. V.</dc:creator>
<dc:creator>Balhoff, J. P.</dc:creator>
<dc:creator>Balk, M. A.</dc:creator>
<dc:creator>Bradford, Y. M.</dc:creator>
<dc:creator>Bridges, Y.</dc:creator>
<dc:creator>Callahan, T. J.</dc:creator>
<dc:creator>Caufield, H.</dc:creator>
<dc:creator>Cuzick, A.</dc:creator>
<dc:creator>Carmody, L. C.</dc:creator>
<dc:creator>Caron, A. R.</dc:creator>
<dc:creator>de Souza, V.</dc:creator>
<dc:creator>Engel, S. R.</dc:creator>
<dc:creator>Fey, P.</dc:creator>
<dc:creator>Fisher, M.</dc:creator>
<dc:creator>Gehrke, S.</dc:creator>
<dc:creator>Grove, C.</dc:creator>
<dc:creator>Hansen, P.</dc:creator>
<dc:creator>Harris, N. L.</dc:creator>
<dc:creator>Harris, M. A.</dc:creator>
<dc:creator>Harris, L.</dc:creator>
<dc:creator>Ibrahim, A.</dc:creator>
<dc:creator>Jacobsen, J. O. B.</dc:creator>
<dc:creator>Köhler, S.</dc:creator>
<dc:creator>McMurry, J. A.</dc:creator>
<dc:creator>Munoz-Fuentes, V.</dc:creator>
<dc:creator>Munoz-Torres, M. C.</dc:creator>
<dc:creator>Parkinson, H.</dc:creator>
<dc:creator>Pendlington, Z. M.</dc:creator>
<dc:creator>Pilgrim, C.</dc:creator>
<dc:creator>Robb, S. M. C.</dc:creator>
<dc:creator>Robinson, P. N.</dc:creator>
<dc:creator>Seager, J.</dc:creator>
<dc:creator>Segerdell, E.</dc:creator>
<dc:creator>Smedley, D.</dc:creator>
<dc:creator>Sollis, E.</dc:creator>
<dc:creator>Toro, S.</dc:creator>
<dc:creator>Vasilevsk</dc:creator>
<dc:date>2024-09-22</dc:date>
<dc:identifier>doi:10.1101/2024.09.18.613276</dc:identifier>
<dc:title><![CDATA[The Unified Phenotype Ontology (uPheno): A framework for cross-species integrative phenomics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-09-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.09.20.614052v1?rss=1">
<title>
<![CDATA[
Achieving Single Cell Acoustic Localisation with Deactivation Super Resolution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.09.20.614052v1?rss=1</link>
<description><![CDATA[
Super-resolution optical microscopy enables optical imaging of cells, molecules and other biological structures beyond the diffraction limit. However, no similar method exists to super-resolve specific cells with ultrasound. Here we introduce Deactivation Super Resolution (DSR), an ultrasound imaging method that uses the acoustic deactivation of genetically encodable contrast agents to super-resolve individual cells with ultrasound as they navigate through structures that cannot be resolved by conventional imaging methods. DSR takes advantage of gas vesicles, which are air-filled sub-micron protein particles that can be expressed in genetically engineered cells to produce ultrasound contrast. Our experimental results show that DSR can distinguish sub-wavelength microstructures that standard B-mode ultrasound images fail to resolve by super- localizing individual mammalian cells. This study provides a proof of concept for the potential of DSR to serve as a super- resolution ultrasound technique for individual cell localization, opening new horizons in the field.
]]></description>
<dc:creator>Smith, C. A. B.</dc:creator>
<dc:creator>Duan, M.</dc:creator>
<dc:creator>Yan, J.</dc:creator>
<dc:creator>Taylor, L.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Tang, M.-X.</dc:creator>
<dc:date>2024-09-24</dc:date>
<dc:identifier>doi:10.1101/2024.09.20.614052</dc:identifier>
<dc:title><![CDATA[Achieving Single Cell Acoustic Localisation with Deactivation Super Resolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-09-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.09.23.614598v1?rss=1">
<title>
<![CDATA[
Probiotic acoustic biosensors for noninvasive imaging of gut inflammation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.09.23.614598v1?rss=1</link>
<description><![CDATA[
Inflammatory bowel diseases (IBD) affect millions of people globally, result in severe symptoms, and are difficult to diagnose and monitor - often necessitating the use of invasive and costly methods such as colonoscopies or endoscopies. Engineered gut bacteria offer a promising alternative due to their ability to persist in the gastrointestinal (GI) tract and sense and respond to specific environmental signals. However, probiotics that have previously been engineered to report on inflammatory and other disease biomarkers in the Gl tract rely on fluorescent or bioluminescent reporters, whose signals cannot be resolved in situ due to the poor penetration of light in tissue. To overcome this limitation, we introduce probiotic biosensors that can be imaged in situ using ultrasound - a widely available, inexpensive imaging modality providing sub-mm spatial resolution deep inside the body. These biosensors are based on the clinically approved probiotic bacterium E. coli Nissle, which we engineered to transiently colonize the GI tract, sense inflammatory biomarkers, and respond by expressing air-filled sound-scattering protein nanostructures called gas vesicles. After optimizing biomolecular signaling circuits to respond sensitively to the biomarkers thiosulfate and tetrathionate and produce strong and stable ultrasound contrast, we validated our living biosensors in vivo by noninvasively imaging antibiotic-induced inflammation in mice. By connecting cell-based diagnostic agents to ultrasound, this "diagnostic yogurt" will make it easier, cheaper, and less painful to diagnose and monitor IBD or other GI conditions.
]]></description>
<dc:creator>Buss, M. T.</dc:creator>
<dc:creator>Zhu, L.</dc:creator>
<dc:creator>Kwon, J. H.</dc:creator>
<dc:creator>Tabor, J. J.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2024-09-25</dc:date>
<dc:identifier>doi:10.1101/2024.09.23.614598</dc:identifier>
<dc:title><![CDATA[Probiotic acoustic biosensors for noninvasive imaging of gut inflammation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-09-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.09.23.614625v1?rss=1">
<title>
<![CDATA[
Application of hsp60 amplicon sequencing to characterize microbial communities associated with juvenile and adult Euprymna scolopes squid 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.09.23.614625v1?rss=1</link>
<description><![CDATA[
The symbiotic relationship between Vibrio (Aliivibrio) fischeri and the Hawaiian bobtail squid, Euprymna scolopes, serves as a key model for understanding host-microbe interactions. Traditional culture-based methods have primarily isolated V. fischeri from the light organs of wild-caught squid, yet culture-independent analyses of this symbiotic microbiome remain limited. This study aims to enhance species-level resolution of bacterial communities associated with E. scolopes using hsp60 amplicon sequencing. We validated our hsp60 sequencing approach using pure cultures and mixed bacterial populations, demonstrating its ability to distinguish V. fischeri from other closely-related vibrios and the possibility of using this approach for strain-level diversity with further optimization. This approach was applied to whole-animal juvenile squid exposed to either seawater or a clonal V. fischeri inoculum, as well as ventate samples and light organ cores from wild-caught adults. V. fischeri accounted for the majority of the identifiable taxa for whole-animal juvenile samples and comprised 94%-99% of amplicon sequence variants (ASVs) for adult light organ core samples, confirming that V. fischeri is the dominant, if not sole, symbiont typically associated with E. scolopes light organs. In one ventate sample, V. fischeri comprised 82% of reads, indicating the potential for non-invasive community assessments using this approach. Analysis of non-V. fischeri ASVs revealed that Bradyrhizobium spp. and other members of the Rhodobacterales order are conserved across juvenile and adult samples. These findings provide insight into the presence of additional microbial associations with the squid host tissue outside of the light organ that have not been previously detected through traditional culture methods.
]]></description>
<dc:creator>Smith, S.</dc:creator>
<dc:creator>Bongrand, C.</dc:creator>
<dc:creator>Lawhorn, S.</dc:creator>
<dc:creator>Ruby, E. G.</dc:creator>
<dc:creator>Septer, A.</dc:creator>
<dc:date>2024-09-25</dc:date>
<dc:identifier>doi:10.1101/2024.09.23.614625</dc:identifier>
<dc:title><![CDATA[Application of hsp60 amplicon sequencing to characterize microbial communities associated with juvenile and adult Euprymna scolopes squid]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-09-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.09.24.614126v1?rss=1">
<title>
<![CDATA[
Characterisation of Gas Vesicles as Cavitation Nuclei for Ultrasound Therapy using Passive Acoustic Mapping 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.09.24.614126v1?rss=1</link>
<description><![CDATA[
Genetically encodable gas filled particles known as gas vesicles (GVs) have shown promise as a biomolecular contrast agent for ultrasound imaging and have the potential to be used as cavitation nuclei for ultrasound therapy. In this study, we used passive acoustic mapping techniques to characterize GV-seeded cavitation, utilizing 0.5 and 1.6 MHz ultrasound over peak rarefactional pressures ranging from 100 to 2200 kPa. We found that GVs produce cavitation for the duration of the first applied pulse, up to at least 5000 cycles, but that bubble activity diminishes rapidly over subsequent pulses. At 0.5 MHz the frequency content of cavitation emissions was predominantly broadband in nature, whilst at 1.6 MHz narrowband content at harmonics of the main excitation frequency dominated. Simulations and high-speed camera imaging suggest that the received cavitation emissions come not from individual GVs but instead from the coalescence of GV-released gas into larger bubbles during the applied ultrasound pulse. These results will aid the future development of GVs as cavitation nuclei in ultrasound therapy.
]]></description>
<dc:creator>Smith, C. A. B.</dc:creator>
<dc:creator>Bar-Zion, A.</dc:creator>
<dc:creator>Wu, Q.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Bau, L.</dc:creator>
<dc:creator>Stride, E.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Coussios, C. C.</dc:creator>
<dc:date>2024-09-26</dc:date>
<dc:identifier>doi:10.1101/2024.09.24.614126</dc:identifier>
<dc:title><![CDATA[Characterisation of Gas Vesicles as Cavitation Nuclei for Ultrasound Therapy using Passive Acoustic Mapping]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-09-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.09.30.615551v1?rss=1">
<title>
<![CDATA[
Neuronal activity regulating the dauer entry decision in Caenorhabditis elegans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.09.30.615551v1?rss=1</link>
<description><![CDATA[
The model nematode Caenorhabditis elegans can choose between two alternative developmental trajectories. Larvae can either become reproductive adults or, under conditions of crowding or low food availability, enter a long-term, stress-resistant diapause known as the dauer stage. Previous studies showed that chemical signals from a secreted larval pheromone promote the dauer trajectory, and that their influence can be antagonised by increased availability of microbial food. The decision is known to be under neuronal control, involving both sensory and interneurons. To make an accurate decision, larvae must collect and compare complex patterns of environmental input over several hours of early larval development. The full composition of this circuit and the algorithm for decision-making are unknown. Here, we used cell-specific chemical silencing to systematically perturb several sensory and interneurons to further elucidate circuit composition. Our results suggest a role for gas-sensing neurons in regulating dauer entry. In addition, we quantitatively characterized the neuronal responses to food and pheromone inputs by measuring calcium traces from ASI and AIA neurons. We found that calcium in ASI increases linearly in response to food, and similarly decreases in response to pheromone, revealing a cellular site of antagonism between these key chemical inputs. Notably, the ASI response persists well beyond removal of the food stimulus, thus encoding a memory of recent food exposure. In contrast, AIA reports instantaneous food availability, and is unaffected by pheromone. We discuss how these findings may inform our understanding of this long-term decision-making process.
]]></description>
<dc:creator>Prakash, S. J.</dc:creator>
<dc:creator>Seyedolmohadesin, M.</dc:creator>
<dc:creator>Zhang, M. G.</dc:creator>
<dc:creator>Cohen, S. M.</dc:creator>
<dc:creator>Gharib, S.</dc:creator>
<dc:creator>Venkatachalam, V.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2024-10-01</dc:date>
<dc:identifier>doi:10.1101/2024.09.30.615551</dc:identifier>
<dc:title><![CDATA[Neuronal activity regulating the dauer entry decision in Caenorhabditis elegans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.02.616363v1?rss=1">
<title>
<![CDATA[
PPARγ downregulation in colonic CD8+ T cells results in epithelial barrier disruption in people with HIV on antiretroviral therapy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.02.616363v1?rss=1</link>
<description><![CDATA[
A hallmark of HIV infection is disruption of intestinal barrier integrity that persists in people with HIV (PWH) despite treatment with antiretroviral therapy (ART). This disruption is central to HIV disease progression, yet the causes remain incompletely understood. We report a novel mechanism by which immunometabolic defects in colon resident CD8+ T cells in PWH lead to intestinal epithelial apoptosis and disruption of intestinal barrier integrity. We show that in PWH, these cells downregulate the lipid sensor peroxisome proliferator-activated receptor-{gamma} (PPAR{gamma}), which results in reduced intracellular lipid droplets, impaired fatty acid oxidation, and acquisition of lipids by CD8+ T cells from intestinal epithelial cells, which then contributes to epithelial cell death. Our findings indicate that HIV-associated immunometabolic dysregulation of colon CD8+ T cell leads to loss of intestinal epithelial homeostasis. These results identify potential new strategies to reduce comorbidities in PWH and other disorders with disrupted intestinal barrier integrity.
]]></description>
<dc:creator>Das Adhikari, U.</dc:creator>
<dc:creator>Froehle, L. M.</dc:creator>
<dc:creator>Pipkin, A. N.</dc:creator>
<dc:creator>Baharlou, H.</dc:creator>
<dc:creator>Linder, A. H.</dc:creator>
<dc:creator>Shah, P.</dc:creator>
<dc:creator>Hussey, A.</dc:creator>
<dc:creator>Zhang, Q.</dc:creator>
<dc:creator>Nyquist, S.</dc:creator>
<dc:creator>Khwaled, S.</dc:creator>
<dc:creator>Chi, F.</dc:creator>
<dc:creator>Goswami, S.</dc:creator>
<dc:creator>Dieffenbach, T. J.</dc:creator>
<dc:creator>Read, B. J.</dc:creator>
<dc:creator>Kim, B.</dc:creator>
<dc:creator>Irvine, D. J.</dc:creator>
<dc:creator>Asowata, O.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Bjorkman, P.</dc:creator>
<dc:creator>Madela, F.</dc:creator>
<dc:creator>Khader, S.</dc:creator>
<dc:creator>Shalek, A. K.</dc:creator>
<dc:creator>Ghebremichael, M.</dc:creator>
<dc:creator>Kloverpris, H.</dc:creator>
<dc:creator>Ringel, A.</dc:creator>
<dc:creator>Yilmaz, O. H.</dc:creator>
<dc:creator>Kwon, D. S.</dc:creator>
<dc:date>2024-10-03</dc:date>
<dc:identifier>doi:10.1101/2024.10.02.616363</dc:identifier>
<dc:title><![CDATA[PPARγ downregulation in colonic CD8+ T cells results in epithelial barrier disruption in people with HIV on antiretroviral therapy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.05.616828v1?rss=1">
<title>
<![CDATA[
A shared code for perceiving and imagining objects in human ventral temporal cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.05.616828v1?rss=1</link>
<description><![CDATA[
Mental imagery is a remarkable phenomenon that allows us to remember previous experiences and imagine new ones. Animal studies have yielded rich insight into mechanisms for visual perception, but the neural mechanisms for visual imagery remain poorly understood. Here, we first determined that [~]80% of visually responsive single neurons in human ventral temporal cortex (VTC) use a distributed axis code to represent objects. We then used that code to reconstruct objects and generate maximally effective synthetic stimuli. Finally, we recorded responses from the same neural population while subjects imagined specific objects and found that [~]40% of axis-tuned VTC neurons recapitulated the visual code. Our findings reveal that visual imagery is supported by reactivation of the same neurons involved in perception, providing single neuron evidence for the existence of a generative model in human VTC.

One Sentence SummarySingle neurons in human temporal cortex use feature axes to encode objects, and imagery reactivates this code.
]]></description>
<dc:creator>Wadia, V. S.</dc:creator>
<dc:creator>Reed, C. M.</dc:creator>
<dc:creator>Chung, J. M.</dc:creator>
<dc:creator>Bateman, L. M.</dc:creator>
<dc:creator>Mamelak, A. N.</dc:creator>
<dc:creator>Rutishauser, U.</dc:creator>
<dc:creator>Tsao, D. Y.</dc:creator>
<dc:date>2024-10-06</dc:date>
<dc:identifier>doi:10.1101/2024.10.05.616828</dc:identifier>
<dc:title><![CDATA[A shared code for perceiving and imagining objects in human ventral temporal cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.07.617048v1?rss=1">
<title>
<![CDATA[
Amygdala Subregion Volumes and Apportionment in Preadolescents -- Associations with Age, Sex, and Body Mass Index 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.07.617048v1?rss=1</link>
<description><![CDATA[
The amygdala, a key limbic structure, is critical to emotional, social, and appetitive behaviors that develop throughout adolescence. Composed of a heterogeneous group of nuclei, questions remain about potential differences in the maturation of its subregions during development. In 3,953 9- and 10-year-olds from the Adolescent Brain Cognitive DevelopmentlZI Study, the CIT168 Amygdala Atlas was used to segment nine amygdala subregions. Linear mixed-effects models were used to examine the effects of age, sex, pubertal stage, and body mass index z-score (BMIz) on subregion volumes and their relative apportionment within the amygdala. Distinct associations were observed between age, sex, and BMIz and whole amygdala volume, subregion volumes, and subregion apportionment. Pubertal stage was not related to amygdala subregion volumes. Age was associated with near-global expansion of amygdala subregions during this developmental period. Female sex was linked to smaller volumes in most amygdala subregions, with larger relative apportionment in the dorsal subregions and smaller apportionment in the basolateral ventral paralaminar subregion. Higher BMIz was associated with smaller volumes in large basolateral subregions, with increased relative apportionment in smaller subregions. These findings provide a foundational context for understanding how developmental variables influence amygdala structure, with implications for understanding future risk for brain disorders.

HighlightsO_LISegmentation of amygdala subregions in nearly 4,000 preadolescents.
C_LIO_LIAge, but not puberty, was associated with a near-global expansion of the amygdala.
C_LIO_LISex differences exist in preadolescent amygdala apportionment.
C_LIO_LIChildhood obesity is linked to differences in the basolateral amygdala.
C_LI
]]></description>
<dc:creator>Overholtzer, L. N.</dc:creator>
<dc:creator>Torgerson, C.</dc:creator>
<dc:creator>Morrel, J.</dc:creator>
<dc:creator>Ahmadi, H.</dc:creator>
<dc:creator>Tyszka, J. M.</dc:creator>
<dc:creator>Herting, M.</dc:creator>
<dc:date>2024-10-11</dc:date>
<dc:identifier>doi:10.1101/2024.10.07.617048</dc:identifier>
<dc:title><![CDATA[Amygdala Subregion Volumes and Apportionment in Preadolescents -- Associations with Age, Sex, and Body Mass Index]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.14.618186v1?rss=1">
<title>
<![CDATA[
Nonlinear Singular Value Decomposition Beamforming for Ultrasound Imaging of Gas Vesicles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.14.618186v1?rss=1</link>
<description><![CDATA[
Ultrasound imaging holds significant promise for the observation of molecular and cellular phenomena through the utilization of acoustic contrast agents and acoustic reporter genes. Optimizing imaging methodologies for enhanced detection represents an imperative advancement in this field. Most advanced techniques relying on amplitude modulation scheme such as cross amplitude modulation (xAM) and ultrafast amplitude modulation (uAM) combined with Hadamard encoded multiplane wave transmissions have shown efficacy in capturing acoustic signals of gas vesicles (GVs). Nonetheless, uAM sequence requires odd- or even-element transmissions leading to imprecise amplitude modulation emitting scheme, and the complex multiplane wave transmission scheme inherently yields overlong pulse durations. xAM sequence is limited in terms of field of view and imaging depth. To overcome these limitations, we introduce an innovative ultrafast imaging sequence called nonlinear singular value decomposition (SVD) beamforming. Our method demonstrated a contrast imaging sensitivity comparable to the current gold-standard xAM and uAM, while requiring 4.8 times less pulse transmissions. With similar number of transmit pulses, nonlinear SVD beamforming outperforms xAM and uAM in terms of an improvement in signal-to-background ratio of + 4.78 {+/-} 0.35 dB and + 8.29 {+/-} 3.52 dB respectively. Additionally, our method provides a higher flexibility in terms of the selection of acoustic pressure amplitude compared to the other methods. Furthermore, it shows a significant potential for application in the realm of ultrasound localization microscopy (ULM), where it stands poised to facilitate the more precise extraction of nonlinear signatures originating from contrast agents.
]]></description>
<dc:creator>Zhang, G.</dc:creator>
<dc:creator>Vert, M.</dc:creator>
<dc:creator>Nouhoum, M.</dc:creator>
<dc:creator>Rivera, E.</dc:creator>
<dc:creator>Haidour, N.</dc:creator>
<dc:creator>Jimenez, A.</dc:creator>
<dc:creator>Deffieux, T.</dc:creator>
<dc:creator>Barral, S.</dc:creator>
<dc:creator>Hersen, P.</dc:creator>
<dc:creator>Rabut, C.</dc:creator>
<dc:creator>Shapiro, M.</dc:creator>
<dc:creator>Tanter, M.</dc:creator>
<dc:date>2024-10-16</dc:date>
<dc:identifier>doi:10.1101/2024.10.14.618186</dc:identifier>
<dc:title><![CDATA[Nonlinear Singular Value Decomposition Beamforming for Ultrasound Imaging of Gas Vesicles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.14.617429v1?rss=1">
<title>
<![CDATA[
Outdoor Air Pollution Relates to Amygdala Subregion Volume and Apportionment in Early Adolescents 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.14.617429v1?rss=1</link>
<description><![CDATA[
BackgroundOutdoor air pollution is associated with an increased risk for psychopathology. Although the neural mechanisms remain unclear, air pollutants may impact mental health by altering limbic brain regions, such as the amygdala. Here, we examine the association between ambient air pollution exposure and amygdala subregion volumes in 9-10-year-olds.

MethodsCross-sectional Adolescent Brain Cognitive DevelopmentSM (ABCD) Study(R) data from 4,473 participants (55.4% male) were leveraged. Air pollution was estimated for each participants primary residential address. Using the probabilistic CIT168 atlas, we quantified total amygdala and 9 distinct subregion volumes from T1- and T2-weighted images. First, we examined how criteria pollutants (i.e., fine particulate matter [PM2.5], nitrogen dioxide, ground-level ozone) and 15 PM2.5 components related with total amygdala volumes using linear mixed-effect (LME) regression. Next, partial least squares correlation (PLSC) analyses were implemented to identify relationships between co-exposure to criteria pollutants as well as PM2.5 components and amygdala subregion volumes. We also conducted complementary analyses to assess subregion apportionment using amygdala relative volume fractions (RVFs).

ResultsNo significant associations were detected between pollutants and total amygdala volumes. Using PLSC, one latent dimension (LD) (52% variance explained) captured a positive association between calcium and several basolateral subregions. LDs were also identified for amygdala RVFs (ranging from 30% to 82% variance explained), with PM2.5 and component co-exposure associated with increases in lateral, but decreases in medial and central, RVFs.

ConclusionsFine particulate and its components are linked with distinct amygdala differences, potentially playing a role in risk for adolescent mental health problems.

Graphical Abstract

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=123 SRC="FIGDIR/small/617429v1_ufig1.gif" ALT="Figure 1">
View larger version (23K):
org.highwire.dtl.DTLVardef@e9f2ecorg.highwire.dtl.DTLVardef@14b677forg.highwire.dtl.DTLVardef@177f8daorg.highwire.dtl.DTLVardef@172dc0c_HPS_FORMAT_FIGEXP  M_FIG C_FIG
]]></description>
<dc:creator>Morrel, J.</dc:creator>
<dc:creator>Overholtzer, L. N.</dc:creator>
<dc:creator>Sukumaran, K.</dc:creator>
<dc:creator>Cotter, D. L.</dc:creator>
<dc:creator>Cardenas-Iniguez, C.</dc:creator>
<dc:creator>Tyszka, J. M.</dc:creator>
<dc:creator>Schwartz, J.</dc:creator>
<dc:creator>Hackman, D. A.</dc:creator>
<dc:creator>Chen, J.-C.</dc:creator>
<dc:creator>Herting, M.</dc:creator>
<dc:date>2024-10-17</dc:date>
<dc:identifier>doi:10.1101/2024.10.14.617429</dc:identifier>
<dc:title><![CDATA[Outdoor Air Pollution Relates to Amygdala Subregion Volume and Apportionment in Early Adolescents]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.18.619139v1?rss=1">
<title>
<![CDATA[
Inducible, but not constitutive, pancreatic REG/Reg isoforms are regulated by intestinal microbiota and pancreatic diseases 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.18.619139v1?rss=1</link>
<description><![CDATA[
The REG/Reg gene locus encodes for a conserved family of potent antimicrobial but also pancreatitis-associated proteins. Here we investigated whether REG/Reg family members differ in their baseline expression levels and abilities to be regulated in the pancreas and gut upon perturbations. We found, in human and mouse, pancreas and gut differed in REG/Reg isoform levels and preferences, with duodenum most resembling the pancreas. Pancreatic acinar cells and intestinal enterocytes were the dominant REG producers. Intestinal symbiotic microbes regulated the expression of the same, select Reg members in gut and pancreas. These Reg members had the most STAT3-binding sites close to the transcription start sites and were partially IL-22 dependent. We thus categorized them as "inducible" and others as "constitutive". Indeed, also in models of pancreatic-ductal adenocarcinoma and pancreatitis, only inducible Reg members were upregulated in pancreas. While intestinal Reg expression remained unchanged upon pancreatic perturbation, pancreatitis altered the microbial composition of the duodenum and feces shortly after disease onset. Our study reveals differential usage and regulation of REG/Reg isoforms as a mechanism for tissue-specific innate immunity, highlights the intimate connection of pancreas and duodenum, and implies a gut-to-pancreas communication axis resulting in a coordinated Reg response.
]]></description>
<dc:creator>Zhou, Y.</dc:creator>
<dc:creator>Komnick, M. R.</dc:creator>
<dc:creator>Sepulveda, F.</dc:creator>
<dc:creator>Liu, G.</dc:creator>
<dc:creator>Nieves-Ortiz, E.</dc:creator>
<dc:creator>Meador, K.</dc:creator>
<dc:creator>Ndatabaye, O.</dc:creator>
<dc:creator>Fatkhullina, A.</dc:creator>
<dc:creator>Wu-Woods, N.</dc:creator>
<dc:creator>Naydenkov, P. M.</dc:creator>
<dc:creator>Kent, J.</dc:creator>
<dc:creator>Christiansen, N.</dc:creator>
<dc:creator>Madariaga, M. L.</dc:creator>
<dc:creator>Witkowski, P.</dc:creator>
<dc:creator>Ismagilov, R. F.</dc:creator>
<dc:creator>Esterhazy, D.</dc:creator>
<dc:date>2024-10-22</dc:date>
<dc:identifier>doi:10.1101/2024.10.18.619139</dc:identifier>
<dc:title><![CDATA[Inducible, but not constitutive, pancreatic REG/Reg isoforms are regulated by intestinal microbiota and pancreatic diseases]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.23.619938v1?rss=1">
<title>
<![CDATA[
CABO-16S : A Combined Archaea, Bacteria, Organelle 16S database for amplicon analysis of prokaryotes and eukaryotes in environmental samples 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.23.619938v1?rss=1</link>
<description><![CDATA[
Identification of both prokaryotic and eukaryotic microorganisms in environmental samples is currently challenged by either the burden of additional sequencing required to obtain both 16S and 18S rRNA sequences or the introduction of multiple biases induced by the use of "universal" primers. Organellar 16S rRNA sequences are automatically amplified and sequenced along with prokaryote 16S rRNA, and may provide an alternative method to identify eukaryotic microorganisms. CABO-16S combines bacterial and archaeal sequences from the SILVA database with 16S rRNA sequences of plastids and other organelles from the PR2 database to enable identification of all 16S rRNA sequences. Comparison of CABO-16S with SILVA 138.2 results in equivalent taxonomic classification of mock communities and increased classification of diverse environmental samples. In particular, identification of phototrophic eukaryotes in shallow seagrass environments, marine waters, and lake waters was increased. CABO-16S also provides the framework to add curated datasets of specialized sequences for further classification of clades which are not currently included in other databases. Addition of sequences obtained from Sanger sequencing of methane seep sediments and curated sequences of the polyphyletic SEEP-SRB1 clade resulted in differentiation of syntrophic and non-syntrophic SEEP-SRB1 in hydrothermal vent sediments. Such additions may simplify analysis of communities contributing to the anaerobic oxidation of methane, and highlight the potential benefit of amending existing training sets with curated sequences when studying extreme or unique environments underrepresented in existing databases.
]]></description>
<dc:creator>Eitel, E. M.</dc:creator>
<dc:creator>Utter, D.</dc:creator>
<dc:creator>Connon, S.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:creator>Murali, R.</dc:creator>
<dc:date>2024-10-23</dc:date>
<dc:identifier>doi:10.1101/2024.10.23.619938</dc:identifier>
<dc:title><![CDATA[CABO-16S : A Combined Archaea, Bacteria, Organelle 16S database for amplicon analysis of prokaryotes and eukaryotes in environmental samples]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.24.619506v1?rss=1">
<title>
<![CDATA[
Optical control of sphingolipid biosynthesis using photoswitchable sphingosines 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.24.619506v1?rss=1</link>
<description><![CDATA[
Sphingolipid metabolism comprises a complex interconnected web of enzymes, metabolites and modes of regulation that influence a wide range of cellular and physiological processes. Deciphering the biological relevance of this network is challenging as numerous intermediates of sphingolipid metabolism are short-lived molecules with often opposing biological activities. Here, we introduce clickable, azobenzene-containing sphingosines, termed caSphs, as light-sensitive substrates for sphingolipid biosynthesis. Photo-isomerization of the azobenzene moiety enables reversible switching between a straight trans- and curved cis-form of the lipids hydrocarbon tail. Combining in vitro enzyme assays with metabolic labeling studies, we demonstrate that trans-to-cis isomerization of caSphs profoundly stimulates their metabolic conversion by ceramide synthases and downstream sphingomyelin synthases. These light-induced changes in sphingolipid production rates are acute, reversible, and can be implemented with great efficiency in living cells. Our findings establish caSphs as versatile tools with unprecedented opportunities to manipulate sphingolipid biosynthesis and function with the spatiotemporal precision of light.
]]></description>
<dc:creator>Kol, M.</dc:creator>
<dc:creator>Novak, A. J. E.</dc:creator>
<dc:creator>Morstein, J.</dc:creator>
<dc:creator>Schroer, C.</dc:creator>
<dc:creator>Sokoya, T.</dc:creator>
<dc:creator>Mensing, S.</dc:creator>
<dc:creator>Korneev, S. M.</dc:creator>
<dc:creator>Trauner, D.</dc:creator>
<dc:creator>Holthuis, J. C. M.</dc:creator>
<dc:date>2024-10-24</dc:date>
<dc:identifier>doi:10.1101/2024.10.24.619506</dc:identifier>
<dc:title><![CDATA[Optical control of sphingolipid biosynthesis using photoswitchable sphingosines]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.23.619839v1?rss=1">
<title>
<![CDATA[
Bystander base editing interferes with visual function restoration in Leber congenital amaurosis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.23.619839v1?rss=1</link>
<description><![CDATA[
Base editors (BEs) have emerged as a powerful tool for gene correction with high activity. However, bystander base editing, a byproduct of BEs, presents challenges for precise editing. Here, we investigated the effects of bystander edits on phenotypic restoration in the context of Leber congenital amaurosis (LCA), a hereditary retinal disorder, as a therapeutic model. We observed that in rd12 of LCA model mice, the highest editing activity version of an adenine base editors (ABEs), ABE8e, generated substantial bystander editing, resulting in missense mutations despite RPE65 expression, preventing restoration of visual function. Through AlphaFold-based mutational scanning and molecular dynamics simulations, we identified that the ABE8e-driven L43P mutation disrupts RPE65 structure and function. Our findings underscore the need for more stringent requirements in developing precise BEs for future clinical applications.
]]></description>
<dc:creator>Lee, S.-H.</dc:creator>
<dc:creator>Wu, J.</dc:creator>
<dc:creator>Im, D.</dc:creator>
<dc:creator>Hwang, G.-H.</dc:creator>
<dc:creator>Jeong, Y. K.</dc:creator>
<dc:creator>Jiang, H.</dc:creator>
<dc:creator>Lee, S. J.</dc:creator>
<dc:creator>Jo, D. H.</dc:creator>
<dc:creator>Goddard, W. A.</dc:creator>
<dc:creator>Kim, J. H.</dc:creator>
<dc:creator>Bae, S.</dc:creator>
<dc:date>2024-10-27</dc:date>
<dc:identifier>doi:10.1101/2024.10.23.619839</dc:identifier>
<dc:title><![CDATA[Bystander base editing interferes with visual function restoration in Leber congenital amaurosis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.28.620504v1?rss=1">
<title>
<![CDATA[
Synaptic composition, activity, mRNA translation and dynamics in combined single-synapse profiling using multimodal imaging 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.28.620504v1?rss=1</link>
<description><![CDATA[
Complex neuronal circuit functions emerge from local, actively regulated synaptic protein levels that interplay with synaptic neurotransmission across heterogenous synapse populations. Understanding the mechanisms by which chemical and disease-associated genetic perturbations impact neuronal circuit functions requires simultaneous measurement of these factors with single-synapse resolution at population scale. Here, we combine in situ multimodal imaging of local mRNA translation, synaptic multiprotein composition, and synapse activity measured via calcium or glutamate fluxes, within the same spatially resolved synapses. We apply this approach of multimodal synapse profiling to study ketamine plasticity. Results map a causal network of NR2A-depletion-induced changes to synaptic scaffolding and receptor proteins, driven by synaptic activity and local mRNA translation, which translates to Grin2a models of schizophrenia in vitro and in vivo. Thus, multimodal synaptomics can reveal mechanistic neurobiology that underlies chemical and genetic perturbations within the context of scalable neuronal cultures, which can serve as models for human disease and therapeutic development.
]]></description>
<dc:creator>Falkovich, R.</dc:creator>
<dc:creator>Aryal, S.</dc:creator>
<dc:creator>Wang, J.</dc:creator>
<dc:creator>Sheng, M.</dc:creator>
<dc:creator>Bathe, M.</dc:creator>
<dc:date>2024-10-28</dc:date>
<dc:identifier>doi:10.1101/2024.10.28.620504</dc:identifier>
<dc:title><![CDATA[Synaptic composition, activity, mRNA translation and dynamics in combined single-synapse profiling using multimodal imaging]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.25.620326v1?rss=1">
<title>
<![CDATA[
Phosphorylation of HP1/Swi6 relieves competition with Suv39/Clr4 on nucleosomes and enables H3K9 trimethyl spreading. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.25.620326v1?rss=1</link>
<description><![CDATA[
Heterochromatin formation in Schizosaccharomyces pombe requires the spreading of histone 3 (H3) Lysine 9 (K9) methylation (me) from nucleation centers by the H3K9 methylase, Suv39/Clr4, and the reader protein, HP1/Swi6. To accomplish this, Suv39/Clr4 and HP1/Swi6 have to associate with nucleosomes both nonspecifically, binding DNA and octamer surfaces and specifically, via recognition of methylated H3K9 by their respective chromodomains. However, how both proteins avoid competition for the same nucleosomes in this process is unclear. Here, we show that phosphorylation tunes oligomerization and the nucleosome affinity of HP1/Swi6 such that it preferentially partitions onto Suv39/Clr4s trimethyl product rather than its unmethylated substrates. Preferential partitioning enables efficient conversion from di-to trimethylation on nucleosomes in vitro and H3K9me3 spreading in vivo. Together, our data suggests that phosphorylation of HP1/Swi6 creates a regime that increases oligomerization and relieves competition with the "read-write" mechanism of Suv39/Clr4, together promoting for productive heterochromatin spreading.
]]></description>
<dc:creator>Kennedy, D. R.</dc:creator>
<dc:creator>Lemiere, J.</dc:creator>
<dc:creator>Tan, C.</dc:creator>
<dc:creator>Simental, E.</dc:creator>
<dc:creator>Braxton, J.</dc:creator>
<dc:creator>Maxwell, R. A.</dc:creator>
<dc:creator>Amine, A. A.</dc:creator>
<dc:creator>Al-Sady, B.</dc:creator>
<dc:date>2024-10-29</dc:date>
<dc:identifier>doi:10.1101/2024.10.25.620326</dc:identifier>
<dc:title><![CDATA[Phosphorylation of HP1/Swi6 relieves competition with Suv39/Clr4 on nucleosomes and enables H3K9 trimethyl spreading.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.28.620469v1?rss=1">
<title>
<![CDATA[
Design of Novel Dehalogenases using Protein Large Language Models 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.28.620469v1?rss=1</link>
<description><![CDATA[
Per- and polyfluoroalkyl substances (PFAS) are toxic compounds linked to cancers, infertility, and vaccine resistance at concentrations above 1 part per trillion. Owing to strong carbon-fluorine bonds, they are persistent in the environment, taking centuries to millennia to degrade. As part of the 2024 iGEM competition, several high school students local to the Pasadena area leveraged recently-developed bioinformatic tools and large language models to discover and design novel reductive dehalogenases predicted to degrade perfluorooctanoic acid (PFOA), a long chain PFAS whose manufacture is prohibited, yet still persists in the environment and drinking water. The team identified 68 enzymes with structural similarity to Acidimicrobium sp. Strain A6 RdhA, the only specific known PFAS degrading enzyme in nature, expressed and refolded 5 of these enzymes in addition to 1 rational, and 3 large language model designs. These designs all have diverse sequences yet all are predicted to retain key substrate and cofactor binding pockets. These enzymes will be assayed on the ability to defluorinate PFOA.
]]></description>
<dc:creator>Garcia, L. N.</dc:creator>
<dc:creator>Nauber, W.</dc:creator>
<dc:creator>Dahlgren, C.</dc:creator>
<dc:creator>Reyes, T.</dc:creator>
<dc:creator>Santos, J.</dc:creator>
<dc:creator>Chung, R.</dc:creator>
<dc:creator>Kapur, M.</dc:creator>
<dc:creator>Barsever, M.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Lourenco, A.</dc:creator>
<dc:date>2024-10-31</dc:date>
<dc:identifier>doi:10.1101/2024.10.28.620469</dc:identifier>
<dc:title><![CDATA[Design of Novel Dehalogenases using Protein Large Language Models]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.28.620588v1?rss=1">
<title>
<![CDATA[
Interactions of N- and C-terminal parts of Ana1 permitting centriole duplication but not elongation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.28.620588v1?rss=1</link>
<description><![CDATA[
The conserved process of centriole duplication requires establishment of a Sas6-centred cartwheel initiated by Plk4s phosphorylation of Ana1/STIL. Subsequently the centriole undergoes conversion to a centrosome requiring its radial expansion and elongation, mediated by a network requiring interactions between Cep135, Ana1/Cep295, and Asterless/Cep152. Here we show that mutant alleles encoding overlapping N- and C-terminal parts of Ana1 are capable of intragenic complementation to rescue radial expansion. This permits recruitment of Asl and thereby centriole duplication and mechanosensory cilia formation to restore the coordination defects of these mutants. This genetic combination also rescues centriole duplication in the male germ line but does not rescue the elongation of the triplet microtubule-containing centrioles of primary spermatocytes and consequently these males are coordinated but sterile. Such centriole elongation is rescued by the continuous, full-length Ana1 sequence. We define a region that when deleted within otherwise intact Ana1 does not permit primary spermatocyte centrioles to elongate but still allows recruitment of Asl. Our findings point to differing demands upon the physical organization of Ana1 for the distinct processes of radial expansion and elongation of centrioles.

IMPACT STATEMENTThe centriole can undergo radial development and duplication using separated parts of the conserved Ana1 protein whereas elongation of centriolar microtubule triplets requires the continuous Ana1 primary sequence.
]]></description>
<dc:creator>Nagy, A.</dc:creator>
<dc:creator>Kovacs, L.</dc:creator>
<dc:creator>Rangone, H.</dc:creator>
<dc:creator>Fu, J.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Glover, D. M.</dc:creator>
<dc:date>2024-10-31</dc:date>
<dc:identifier>doi:10.1101/2024.10.28.620588</dc:identifier>
<dc:title><![CDATA[Interactions of N- and C-terminal parts of Ana1 permitting centriole duplication but not elongation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.28.620681v1?rss=1">
<title>
<![CDATA[
Spatial Transcriptomics Reveals the Temporal Architecture of the Seminiferous Epithelial Cycle and Precise Sertoli-Germ Synchronization 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.28.620681v1?rss=1</link>
<description><![CDATA[
Spermatogenesis is characterized by the seminiferous epithelial cycle, a periodic pattern of germ cell differentiation with a wave-like progression along the length of seminiferous tubules. While key signaling and metabolic components of the cycle are known, the transcriptional changes across the cycle and the correlations between germ cell and somatic lineages remain undefined. Here, we use spatial transcriptomics via RNA SeqFISH+ to profile 2,638 genes in 216,090 cells in mouse testis and identify a periodic transcriptional pattern across tubules that precisely recapitulates the seminiferous epithelial cycle, enabling us to map cells to specific timepoints along the developmental cycle. Analyzing gene expression in somatic cells reveals that Sertoli cells exhibit a cyclic transcriptional profile closely synchronized with germ cell development while other somatic cells do not demonstrate such synchronization. Remarkably, in mouse testis with drug-induced ablation of germ cells, Sertoli cells independently maintain their cyclic transcriptional dynamics. By analyzing expression data, we identify an innate retinoic acid cycle, a network of transcription factors with cyclic activation, and signaling from germ cells that could interact with this network. Together, this work leverages spatial geometries for mapping the temporal dynamics and reveals a regulatory mechanism in spermatogenesis where Sertoli cells oscillate and coordinate with the cyclical progression of germ cell development.

Graphical Abstract

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/620681v2_ufig1.gif" ALT="Figure 1">
View larger version (54K):
org.highwire.dtl.DTLVardef@10a78c7org.highwire.dtl.DTLVardef@7f5a95org.highwire.dtl.DTLVardef@113f6b6org.highwire.dtl.DTLVardef@1aa41f3_HPS_FORMAT_FIGEXP  M_FIG C_FIG
]]></description>
<dc:creator>Chakravorty, A.</dc:creator>
<dc:creator>Simons, B. D.</dc:creator>
<dc:creator>Yoshida, S.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:date>2024-10-31</dc:date>
<dc:identifier>doi:10.1101/2024.10.28.620681</dc:identifier>
<dc:title><![CDATA[Spatial Transcriptomics Reveals the Temporal Architecture of the Seminiferous Epithelial Cycle and Precise Sertoli-Germ Synchronization]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.10.31.621310v1?rss=1">
<title>
<![CDATA[
Chromatin-associated lncRNA-splicing factor condensates regulate hypoxia responsive RNA processing of genes pre-positioned near nuclear speckles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.10.31.621310v1?rss=1</link>
<description><![CDATA[
Hypoxia-induced alternative splicing (AS) regulates tumor progression and metastasis. Little is known about how such AS is controlled and whether higher-order genome and nuclear domain (ND) organizations dictate these processes. We observe that hypoxia-responsive alternatively spliced genes position near nuclear speckle (NS), the ND that enhances splicing efficiency. NS-resident MALAT1 long noncoding RNA, induced in response to hypoxia, regulates hypoxia-responsive AS. MALAT1 achieves this by organizing the SR-family of splicing factor, SRSF1, near NS and regulating the binding of SRSF1 to pre-mRNAs. Mechanistically, MALAT1 enhances the recruitment of SRSF1 to elongating RNA polymerase II (pol II) by promoting the formation of phase-separated condensates of SRSF1, which are preferentially recognized by pol II. During hypoxia, MALAT1 regulates spatially organized AS by establishing a threshold SRSF1 concentration near NSs, potentially by forming condensates, critical for pol II-mediated recruitment of SRSF1 to pre-mRNAs.
]]></description>
<dc:creator>Song, Y. J.</dc:creator>
<dc:creator>Shinn, M. K.</dc:creator>
<dc:creator>Bangru, S.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Sun, Q.</dc:creator>
<dc:creator>Hao, Q.</dc:creator>
<dc:creator>Chaturvedi, P.</dc:creator>
<dc:creator>Freier, S. M.</dc:creator>
<dc:creator>Perez-Pinera, P.</dc:creator>
<dc:creator>Nelson, E. R.</dc:creator>
<dc:creator>Belmont, A. S.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:creator>Prasantth, S. G.</dc:creator>
<dc:creator>Kalsotra, A.</dc:creator>
<dc:creator>Pappu, R. V.</dc:creator>
<dc:creator>Kannanganattu, P. V.</dc:creator>
<dc:date>2024-10-31</dc:date>
<dc:identifier>doi:10.1101/2024.10.31.621310</dc:identifier>
<dc:title><![CDATA[Chromatin-associated lncRNA-splicing factor condensates regulate hypoxia responsive RNA processing of genes pre-positioned near nuclear speckles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.11.07.622495v1?rss=1">
<title>
<![CDATA[
Phenotypic plasticity in bacterial elongation among closely related species 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.11.07.622495v1?rss=1</link>
<description><![CDATA[
Cell elongation is a fundamental component of the bacterial cell cycle and has been studied over many decades, in part owing to its mechanisms being a target of numerous antibiotic classes. While several distinct modes of cell elongation have been described, these studies have largely relied on a handful of model bacterial species. Therefore, we have a limited view of the diversity of cell elongation approaches that are employed by bacteria, and how these vary in response to evolutionary and environmental influences. Here, by employing fluorescent D-amino acids (FDAAs) to track the spatiotemporal dynamics of elongation, we reveal previously unsuspected diversity of elongation modes among closely related species of the Caulobacteraceae, with species-specific combinations of dispersed, midcell and polar elongation that can be either unidirectional or bidirectional. Using genetic, cell biology, and phylogenetic approaches, we demonstrate that evolution of unidirectional-midcell elongation is accompanied by changes in the localization pattern of the peptidoglycan synthase PBP2 and infer that elongation complexes display a high degree of phenotypic plasticity, both among the Caulobacteraceae and more widely among the Alphaproteobacteria. Demonstration that even closely related bacterial species employ highly distinct mechanisms of cell elongation reshapes our understanding of the evolution and regulation of bacterial cell growth, with broad implications for bacterial morphology, adaptation, and antibiotic resistance.
]]></description>
<dc:creator>Delaby, M.</dc:creator>
<dc:creator>Yang, L.</dc:creator>
<dc:creator>Jacq, M.</dc:creator>
<dc:creator>Gallagher, K. A.</dc:creator>
<dc:creator>Kysela, D. T.</dc:creator>
<dc:creator>Hughes, V.</dc:creator>
<dc:creator>Pulido, F.</dc:creator>
<dc:creator>Veyrier, F. J.</dc:creator>
<dc:creator>VanNieuwenhze, M. S.</dc:creator>
<dc:creator>Brun, Y. V.</dc:creator>
<dc:date>2024-11-07</dc:date>
<dc:identifier>doi:10.1101/2024.11.07.622495</dc:identifier>
<dc:title><![CDATA[Phenotypic plasticity in bacterial elongation among closely related species]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.11.08.622687v1?rss=1">
<title>
<![CDATA[
Conformational plasticity of mitochondrial VDAC2 controls the kinetics of its interaction with cytosolic proteins 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.11.08.622687v1?rss=1</link>
<description><![CDATA[
The Voltage Dependent Anion Channel (VDAC) is the major conduit of water-soluble metabolites and small ions into and out of the mitochondria. In mammals, VDAC exists in three isoforms, VDAC1, VDAC2, and VDAC3, each characterized by distinct tissue-dependent distribution and physiological role. VDAC2 is the most notable among the three isoforms because its knockout results in embryonic lethality and regulates the BAK/BAX-dependent apoptosis pathways. Yet, understanding of the biophysical underpinnings of VDAC2 functions remains limited. In this study, we reevaluate VDAC2s properties, utilizing recombinant human VDAC2 WT and its three mutants - cysteine-less VDAC2, VDAC2 with truncated first 11 residues, and E84A - to explore the biophysical basis that distinguishes VDAC2 from the other isoforms using single-molecule electrophysiology. We found that contrary to VDAC1 and VDAC3, which are characterized by a unique open state, VDAC2 displays dynamic switching between a few high-conductive anion-selective substates. We employed -synuclein (Syn) - a known potent cytosolic regulator of VDAC1 and VDAC3 - as a sensitive molecular probe to show that it induces characteristic blockage events in all open substates of VDAC2 but with up to ten-fold different on-rates and blockage times. A substate with higher conductance always corresponds to a higher on-rate of the Syn-VDAC2 interaction but proportionally lower blockage times. This gives the same equilibrium constant for all substates, thus resulting in the same affinity of the Syn-VDAC2 interaction. The pronounced difference is limited to the kinetic parameters, suggesting that once the Syn molecule is captured, its physical state and free energy are the same for all substates. These striking results imply that the Syn molecule senses the dynamic structural variations within the channel prior to its final capture by the pore. We propose that the discovered conformational flexibility may allow VDAC2 to recognize a larger number of binding partners, thus explaining the physiological significance of this isoform, namely, its ability to adapt to mitochondrial metabolic conditions in cells dynamically.
]]></description>
<dc:creator>Rosencrans, W. M.</dc:creator>
<dc:creator>Khuntia, H.</dc:creator>
<dc:creator>Larimi, M. G.</dc:creator>
<dc:creator>Mahalakshmi, R.</dc:creator>
<dc:creator>Yu, T.-Y. D.</dc:creator>
<dc:creator>Bezrukov, S. M.</dc:creator>
<dc:creator>Rostovtseva, T. K.</dc:creator>
<dc:date>2024-11-11</dc:date>
<dc:identifier>doi:10.1101/2024.11.08.622687</dc:identifier>
<dc:title><![CDATA[Conformational plasticity of mitochondrial VDAC2 controls the kinetics of its interaction with cytosolic proteins]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.11.13.623425v1?rss=1">
<title>
<![CDATA[
Discovery of lydiamycin A biosynthetic gene cluster in the plant pathogen Rhodococcus fascians guides structural revision and identification of molecular target 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.11.13.623425v1?rss=1</link>
<description><![CDATA[
The natural products actinonin and matlystatin feature an N-hydroxy-2-pentyl-succinamyl (HPS) chemophore that facilitates metal chelation and confers their metalloproteinase inhibitory activity. Actinonin is the most potent natural inhibitor of peptide deformylase (PDF) and exerts antimicrobial and herbicidal bioactivity by disrupting protein synthesis. Here, we used a genomics-led approach to identify candidate biosynthetic gene clusters (BGCs) hypothesised to produce novel HPS-containing natural products. We show that one of these BGCs is on the pathogenicity megaplasmid of the plant pathogen Rhodococcus fascians and produces lydiamycin A, a macrocyclic pentapeptide. The presence of genes predicted to make a HPS-like chemophore informed the structural recharacterisation of lydiamycin via NMR and crystallography to show it features a rare 2-pentyl-succinyl chemophore. We demonstrate that lydiamycin A inhibits bacterial PDF in vitro and show that a cluster-situated PDF gene confers resistance to lydiamycin A, representing a novel self-immunity mechanism associated with the production of a PDF inhibitor. In planta competition assays showed that lydiamycin enhances the fitness of R. fascians during plant colonisation. This study highlights how a BGC can inform the structure, biochemical target and ecological function of a natural product.
]]></description>
<dc:creator>Ford, J. J.</dc:creator>
<dc:creator>Santos-Aberturas, J.</dc:creator>
<dc:creator>Hems, E. S.</dc:creator>
<dc:creator>Sallmen, J. W.</dc:creator>
<dc:creator>Bögeholz, L. A. K.</dc:creator>
<dc:creator>Polturak, G.</dc:creator>
<dc:creator>Osbourn, A.</dc:creator>
<dc:creator>Wright, J. A.</dc:creator>
<dc:creator>Rodnina, M. V.</dc:creator>
<dc:creator>Vereecke, D.</dc:creator>
<dc:creator>Francis, I. M.</dc:creator>
<dc:creator>Truman, A. W.</dc:creator>
<dc:date>2024-11-13</dc:date>
<dc:identifier>doi:10.1101/2024.11.13.623425</dc:identifier>
<dc:title><![CDATA[Discovery of lydiamycin A biosynthetic gene cluster in the plant pathogen Rhodococcus fascians guides structural revision and identification of molecular target]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.11.14.623368v1?rss=1">
<title>
<![CDATA[
Real-time volumetric imaging of cells and molecules in deep tissues with Takoyaki ultrasound 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.11.14.623368v1?rss=1</link>
<description><![CDATA[
Acoustic contrast agents and reporter genes play a critical role in allowing ultrasound to visualize blood flow, map molecules and track cellular function in opaque living organisms. However, existing ultrasound methods to image acoustic contrast agents predominantly focus on 2D planar imaging, while the biological phenomena of interest unfurl in three dimensions. Here, we introduce a method for efficient, dynamic imaging of contrast agents and reporter genes in 3D using multiplexed matrix array transducers. Our "Takoyaki" pulse sequence uses the simultaneous scanning of multiple focal points to excite contrast agents with sufficient acoustic pressure for nonlinear imaging while efficiently covering 3D space. Through in vitro experiments, we first show that the Takoyaki sequence produces highly sensitive volume images of gas vesicle contrast agents and compare its performance with alternative imaging schemes. We then establish its utility in cellular imaging in vivo by visualizing acoustic reporter gene-expressing tumors in a mouse model of glioblastoma. Finally, we demonstrate real-time volumetric imaging by tracking the dynamics of fluid motion in brain ventricles after intraventricular contrast injection. Takoyaki imaging enables a more comprehensive understanding of biological processes by providing spatiotemporal information in 3D within the constraints of accessible multiplexed matrix array systems.
]]></description>
<dc:creator>Lee, S.</dc:creator>
<dc:creator>Wu, D.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Rabut, C.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2024-11-15</dc:date>
<dc:identifier>doi:10.1101/2024.11.14.623368</dc:identifier>
<dc:title><![CDATA[Real-time volumetric imaging of cells and molecules in deep tissues with Takoyaki ultrasound]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.11.15.623713v1?rss=1">
<title>
<![CDATA[
Filling-in of the Blindspot is Multisensory 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.11.15.623713v1?rss=1</link>
<description><![CDATA[
We asked three questions about multisensory perception across the physiological blind spot: (1) Does audiovisual integration persist without bottom-up visual input? (2) Does the brain adjust its sensory uncertainties and priors accordingly? (3) Are the underlying causal-inference computations preserved?

Participants judged flashes and beeps in an audiovisual illusion presented across the blind spot or a matched control location. Responses were fit with a Bayesian Causal Inference (BCI) model, estimating sensory noise, numerosity priors, and causal-inference priors under multiple decision strategies evaluated using BIC.

Illusions were robust at both locations, indicating preserved integration. Model fits showed higher visual uncertainty and broader prior expectations at the blind spot, while auditory precision and the causal prior remained stable. Thus, the computational architecture of causal inference is maintained, but its parameters flexibly adapt to local sensory reliability.

These findings demonstrate that perceptual inference remains intact even in regions without retinal input, achieved by adjusting internal uncertainty rather than altering core multisensory computations.
]]></description>
<dc:creator>Chan, A.</dc:creator>
<dc:creator>Stiles, N. R. B.</dc:creator>
<dc:creator>Levitan, C. A.</dc:creator>
<dc:creator>Tanguay, A. R.</dc:creator>
<dc:creator>Shimojo, S.</dc:creator>
<dc:date>2024-11-15</dc:date>
<dc:identifier>doi:10.1101/2024.11.15.623713</dc:identifier>
<dc:title><![CDATA[Filling-in of the Blindspot is Multisensory]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.11.19.624390v1?rss=1">
<title>
<![CDATA[
Cellular behavior analysis from live-cell imaging of TCR T cell-cancer cell interactions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.11.19.624390v1?rss=1</link>
<description><![CDATA[
T cell therapies, such as chimeric antigen receptor (CAR) T cells and T cell receptor (TCR) T cells, are a growing class of anti-cancer treatments. However, expansion to novel indications and beyond last-line treatment requires engineering cells dynamic population behaviors. Here we develop the tools for cellular behavior analysis of T cells from live-cell imaging, a common and inexpensive experimental setup used to evaluate engineered T cells. We first develop a state-of-the-art segmentation and tracking pipeline, Caliban, based on human-in-the-loop deep learning. We then build the Occident pipeline to collect a catalog of phenotypes that characterize cell populations, morphology, movement, and interactions in co-cultures of modified T cells and antigen-presenting tumor cells. We use Caliban and Occident to interrogate how interactions between T cells and cancer cells differ when beneficial knock-outs of RASA2 and CUL5 are introduced into TCR T cells. We apply spatiotemporal models to quantify T cell recruitment and proliferation after interactions with cancer cells. We discover that, compared to a safe harbor knockout control, RASA2 knockout T cells have longer interaction times with cancer cells leading to greater T cell activation and killing efficacy, while CUL5 knockout T cells have increased proliferation rates leading to greater numbers of T cells for hunting. Together, segmentation and tracking from Caliban and phenotype quantification from Occident enable cellular behavior analysis to better engineer T cell therapies for improved cancer treatment.
]]></description>
<dc:creator>Verma, A.</dc:creator>
<dc:creator>Yu, C.</dc:creator>
<dc:creator>Bachl, S.</dc:creator>
<dc:creator>Lopez, I.</dc:creator>
<dc:creator>Schwartz, M. S.</dc:creator>
<dc:creator>Moen, E.</dc:creator>
<dc:creator>Kale, N.</dc:creator>
<dc:creator>Ching, C.</dc:creator>
<dc:creator>Miller, G.</dc:creator>
<dc:creator>Dougherty, T.</dc:creator>
<dc:creator>Pao, E.</dc:creator>
<dc:creator>Graf, W.</dc:creator>
<dc:creator>Ward, C.</dc:creator>
<dc:creator>Jena, S. G.</dc:creator>
<dc:creator>Marson, A.</dc:creator>
<dc:creator>Carnevale, J.</dc:creator>
<dc:creator>Van Valen, D. A.</dc:creator>
<dc:creator>Engelhardt, B. E.</dc:creator>
<dc:date>2024-11-21</dc:date>
<dc:identifier>doi:10.1101/2024.11.19.624390</dc:identifier>
<dc:title><![CDATA[Cellular behavior analysis from live-cell imaging of TCR T cell-cancer cell interactions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.11.21.624570v1?rss=1">
<title>
<![CDATA[
Switchable client specificity in a dual functional chaperone coordinates light harvesting complex biogenesis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.11.21.624570v1?rss=1</link>
<description><![CDATA[
The proper assembly of light harvesting complexes (LHCs) is critical for photosynthesis and requires the biogenesis of light-harvesting chlorophyll a,b-binding proteins (LHCPs) to be coordinated with the biosynthesis of chlorophylls (Chl). The mechanism underlying this coordination is not well understood. Here we show that a conserved molecular chaperone in chloroplasts, cpSRP43, provides a molecular thermostat that helps maintain this coordination. cpSRP43 undergoes a conformational rearrangement between a well-folded closed state and a partially disordered open state. Closed cpSRP43 is dedicated to the de novo biogenesis of LHCPs, whereas open cpSRP43 protects multiple Chl biosynthesis enzymes from heat-induced destabilization. Rising temperature shifts cpSRP43 to the open state and thus enables it to protect Chl biosynthesis enzymes that are heat-destabilized. Our results reveal the molecular basis of a post-translational mechanism for the thermo-adaptation of LHC biogenesis. They also demonstrate how an ATP-independent chaperone uses conformational dynamics to switch its activity and client selectivity, thereby adapting to different proteostatic demands under shifting environmental conditions.

TeaserA thermo-switchable molecular chaperone helps coordinate light harvesting complex assembly during photosynthesis.
]]></description>
<dc:creator>Siegel, A. R.</dc:creator>
<dc:creator>Kroon, G.</dc:creator>
<dc:creator>Wright, P. E.</dc:creator>
<dc:creator>Shan, S.-o.</dc:creator>
<dc:date>2024-11-21</dc:date>
<dc:identifier>doi:10.1101/2024.11.21.624570</dc:identifier>
<dc:title><![CDATA[Switchable client specificity in a dual functional chaperone coordinates light harvesting complex biogenesis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.11.22.624901v1?rss=1">
<title>
<![CDATA[
Efficient pheromone navigation via antagonistic detectors 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.11.22.624901v1?rss=1</link>
<description><![CDATA[
Chemotaxis to a moving potential mate that emits a volatile sex pheromone poses a navigation challenge requiring rapid, precise responses to maximize reproductive success. Volatile chemicals form gradients that differ from soluble compounds, potentially making navigation based on comparisons between spatially separated sensors unreliable for small-bodied animals. Here we show that, rather than a simple spatial comparison, Caenorhabditis elegans males employ an antagonistic strategy, comparing inputs from sex-shared head (AWA) and male-specific tail (PHD) sensory neurons with distinct response properties. Despite sharing a receptor, SRD-1, these detectors play different roles: AWAs promote forward movement and acceleration, while PHDs induce reversals and deceleration. In rising pheromone gradients, AWA activity dominates; in falling gradients, AWA inactivates, allowing PHD to correct trajectories. AWAs are essential for mate-searching, while PHDs are crucial for complex tasks. A minimal computational model reproduces these behaviors and infers how head-tail signals are combined. Thus, a sexually dimorphic, antagonistic sensory system enables adaptive navigation in dynamic environments
]]></description>
<dc:creator>Wan, X.</dc:creator>
<dc:creator>Zhou, T.</dc:creator>
<dc:creator>Susoy, V.</dc:creator>
<dc:creator>Park, C. F.</dc:creator>
<dc:creator>Groaz, A.</dc:creator>
<dc:creator>Brady, J. F.</dc:creator>
<dc:creator>Samuel, A. D. T.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2024-11-22</dc:date>
<dc:identifier>doi:10.1101/2024.11.22.624901</dc:identifier>
<dc:title><![CDATA[Efficient pheromone navigation via antagonistic detectors]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.11.22.624928v1?rss=1">
<title>
<![CDATA[
Cells transit through a quiescent-like state to convert to neurons at high rates 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.11.22.624928v1?rss=1</link>
<description><![CDATA[
While transcription factors (TFs) provide essential cues for directing and redirecting cell fate, TFs alone are insufficient to drive cells to adopt alternative fates. Rather, transcription factors rely on receptive cell states to induce novel identities. Cell state emerges from and is shaped by cellular history and the activity of diverse processes. Here, we define the cellular and molecular properties of a highly receptive state amenable to transcription factor-mediated direct conversion from fibroblasts to induced motor neurons. Using a well-defined model of direct conversion to a post-mitotic fate, we identify the highly proliferative, receptive state that transiently emerges during conversion. Through examining chromatin accessibility, histone marks, and nuclear features, we find that cells reprogram from a state characterized by global reductions in nuclear size and transcriptional activity. Supported by globally increased levels of H3K27me3, cells enter a quiescent-like state of reduced RNA metabolism and elevated expression of REST and p27, markers of quiescent neural stem cells. From this transient state, cells convert to neurons at high rates. Inhibition of Ezh2, the catalytic subunit of PRC2 that deposits H3K27me3, abolishes conversion. Our work offers a roadmap to identify global changes in cellular processes that define cells with different conversion potentials that may generalize to other cell-fate transitions.

HighlightsO_LIProliferation drives cells to a compact nuclear state that is receptive to TF-mediated conversion.
C_LIO_LIIncreased receptivity to TFs corresponds to reduced nuclear volumes.
C_LIO_LIReprogrammable cells display global, genome-wide increases in H3K27me3.
C_LIO_LIHigh levels of H3K27me3 support cells transits through a state of altered RNA metabolism.
C_LIO_LIInhibition of Ezh2 increases nuclear size, reduces the expression of the quiescence marker p27.
C_LIO_LIAcute inhibition of Ezh2 abolishes motor neuron conversion.
C_LI

One Sentence SummaryCells transit through a quiescent-like state characterized by global reductions in nuclear size and transcriptional activity to convert to neurons at high rates.

Graphical Abstract

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=143 SRC="FIGDIR/small/624928v1_ufig1.gif" ALT="Figure 1">
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org.highwire.dtl.DTLVardef@ee2127org.highwire.dtl.DTLVardef@1c2a39dorg.highwire.dtl.DTLVardef@183bf46org.highwire.dtl.DTLVardef@82b98d_HPS_FORMAT_FIGEXP  M_FIG C_FIG
]]></description>
<dc:creator>Beitz, A. M.</dc:creator>
<dc:creator>Teves, J.</dc:creator>
<dc:creator>Oakes, C. G.</dc:creator>
<dc:creator>Johnstone, C. P.</dc:creator>
<dc:creator>Wang, N. B.</dc:creator>
<dc:creator>Brickman, J. M.</dc:creator>
<dc:creator>Galloway, K. E.</dc:creator>
<dc:date>2024-11-25</dc:date>
<dc:identifier>doi:10.1101/2024.11.22.624928</dc:identifier>
<dc:title><![CDATA[Cells transit through a quiescent-like state to convert to neurons at high rates]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.11.28.623729v1?rss=1">
<title>
<![CDATA[
Optogenetic manipulation of nuclear Dorsal reveals temporal requirements and consequences for transcription 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.11.28.623729v1?rss=1</link>
<description><![CDATA[
Morphogen gradients convey essential spatial information during tissue patterning. While both concentration and timing of morphogen exposure are crucial, how cells interpret these graded inputs remains challenging to address. We employed an optogenetic system to acutely and reversibly modulate the nuclear concentration of the morphogen Dorsal (DL), homologue of NF-{kappa}B, which orchestrates dorso-ventral patterning in the Drosophila embryo. By controlling DL nuclear concentration while simultaneously recording target gene outputs in real time, we identified a critical window for DL action that is required to instruct patterning, and characterized the resulting effect on spatio-temporal transcription of target genes in terms of timing, coordination, and bursting. We found that a transient decrease in nuclear DL levels at nuclear cycle 13 leads to reduced expression of the mesoderm-associated gene snail (sna) and partial derepression of the neurogenic ectoderm-associated target short gastrulation (sog) in ventral regions. Surprisingly, the mispatterning elicited by this transient change in DL is detectable at the level of single cell transcriptional bursting kinetics, specifically affecting long inter-burst durations. Our approach of using temporally-resolved and reversible modulation of a morphogen in vivo, combined with mathematical modeling, establishes a framework for understanding the stimulus-response relationships that govern embryonic patterning.
]]></description>
<dc:creator>Pimmett, V. L.</dc:creator>
<dc:creator>McGehee, J.</dc:creator>
<dc:creator>Trullo, A.</dc:creator>
<dc:creator>Douaihy, M.</dc:creator>
<dc:creator>Radulescu, O.</dc:creator>
<dc:creator>Stathopoulos, A.</dc:creator>
<dc:creator>Lagha, M.</dc:creator>
<dc:date>2024-11-28</dc:date>
<dc:identifier>doi:10.1101/2024.11.28.623729</dc:identifier>
<dc:title><![CDATA[Optogenetic manipulation of nuclear Dorsal reveals temporal requirements and consequences for transcription]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.11.26.625503v1?rss=1">
<title>
<![CDATA[
Mapping essential somatic hypermutations in a CD4-binding site bNAb informs HIV-1 vaccine design 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.11.26.625503v1?rss=1</link>
<description><![CDATA[
HIV-1 broadly-neutralizing antibodies (bNAbs) targeting the CD4-binding site (CD4bs) contain rare features that pose challenges to elicit these bNAbs through vaccination. The IOMA-class of CD4bs bNAbs includes fewer rare features and somatic hypermutations (SHMs) to achieve broad neutralization, thus presenting a potentially accessible pathway for vaccine-induced bNAb development. Here, we created a library of IOMA variants in which each SHM was individually reverted to the inferred germline (iGL) counterpart to investigate the roles of SHMs in conferring IOMAs neutralization potency and breadth. Impacts on neutralization for each variant were evaluated, and this information was used to design minimally-mutated IOMA-class variants (IOMAmin) that incorporated the fewest SHMs required for achieving IOMAs neutralization breadth. A cryo-EM structure of an IOMAmin variant bound to Env was used to further interpret characteristics of IOMA variants to elucidate how IOMAs structural features correlate with its neutralization mechanism, informing the design of IOMA-targeting immunogens.

HighlightsIOMAmin variants with reduced SHMs retain neutralization potency and breadth.

Cryo-EM structure reveals IOMAmin preserves key Env interactions despite fewer SHMs.

IOMA variants with mutations in CDRH3 and CDRL1 fail to improve neutralization.
]]></description>
<dc:creator>Dam, K.-M. A.</dc:creator>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>Li, Y. E.</dc:creator>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Gnanapragasam, P. N. P.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Seaman, M. S.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2024-11-29</dc:date>
<dc:identifier>doi:10.1101/2024.11.26.625503</dc:identifier>
<dc:title><![CDATA[Mapping essential somatic hypermutations in a CD4-binding site bNAb informs HIV-1 vaccine design]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.12.02.625538v1?rss=1">
<title>
<![CDATA[
Hydrogel encapsulation of a designed fluorescent protein biosensor for continuous measurements of sub-100 nanomolar nicotine 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.12.02.625538v1?rss=1</link>
<description><![CDATA[
The reinforcing and addictive properties of nicotine result from concentration- and time-dependent activation, desensitization, and upregulation of nicotinic acetylcholine receptors. However, time-resolved [nicotine] measurement in people who consume nicotine is challenging, as current approaches are expensive, invasive, tedious, and discontinuous. To address the challenge of continuous nicotine monitoring in human biofluids, we report the encapsulation of a purified, previously developed fluorescent biosensor protein, iNicSnFR12, into acrylamide hydrogels and polyethylene glycol diacrylate (PEGDA) hydrogels. We optimized the hydrogels for optical clarity and straightforward slicing. With fluorescence photometry of the hydrogels in a microscope and an integrated miniscope, [nicotine] is detected within a few min at the smoking- and vaping-relevant level of 10 - 100 nM (1.62 - 16.2 ng/ml), even in a 250 {micro}m thick hydrogel at the end of 400 {micro}m dia multimode fiber optic. Concentration-response relations are consistent with previous measurements on isolated iNicSnFR12. Leaching of iN-icSnFR12 from the hydrogel and inactivation of iNicSnFR12 are minimal for several days, and nicotine can be detected for at least 10 months after casting. This work provides the molecular, photophysical, and mechanical bases for personal, wearable continuous [nicotine] monitoring, with straightforward extensions to existing, homologous "iDrugSnFR" proteins for other abused and prescribed drugs.
]]></description>
<dc:creator>Nichols, A. L.</dc:creator>
<dc:creator>Marotta, C. B.</dc:creator>
<dc:creator>Wagenaar, D. A.</dc:creator>
<dc:creator>Mayo, S. L.</dc:creator>
<dc:creator>Dougherty, D. A.</dc:creator>
<dc:creator>Lester, H. A.</dc:creator>
<dc:date>2024-12-02</dc:date>
<dc:identifier>doi:10.1101/2024.12.02.625538</dc:identifier>
<dc:title><![CDATA[Hydrogel encapsulation of a designed fluorescent protein biosensor for continuous measurements of sub-100 nanomolar nicotine]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-12-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.12.06.627252v1?rss=1">
<title>
<![CDATA[
A CRISPRi Library Screen in Group B Streptococcus Identifies Surface Immunogenic Protein (Sip) as a Mediator of Multiple Host Interactions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.12.06.627252v1?rss=1</link>
<description><![CDATA[
Group B Streptococcus (GBS; Streptococcus agalactiae) is an important pathobiont capable of colonizing various host environments, contributing to severe perinatal infections. Surface proteins play critical roles in GBS-host interactions, yet comprehensive studies of these proteins functions have been limited by genetic manipulation challenges. This study leveraged a CRISPR interference (CRISPRi) library to target genes encoding surface-trafficked proteins in GBS, identifying their roles in modulating macrophage cytokine responses. Bioinformatic analysis of 654 GBS genomes revealed 66 conserved surface protein genes. Using a GBS strain expressing chromosomally integrated dCas9, we generated and validated CRISPRi strains targeting these genes. THP-1 macrophage-like cells were exposed to ethanol-killed GBS variants, and pro-inflammatory cytokines TNF- and IL-1{beta} were measured. Notably, knockdown of the sip gene, encoding the Surface Immunogenic Protein (Sip), significantly increased IL-1{beta} secretion, implicating Sip in caspase-1-dependent regulation. Further, {Delta}sip mutants demonstrated impaired biofilm formation, reduced adherence to human fetal membranes, and diminished uterine persistence in a mouse colonization model. These findings suggest Sip modulates GBS- host interactions critical for pathogenesis, underscoring its potential as a therapeutic target or vaccine component.
]]></description>
<dc:creator>Firestone, K.</dc:creator>
<dc:creator>Gopalakrishna, K. P.</dc:creator>
<dc:creator>Rogers, L. M.</dc:creator>
<dc:creator>Peters, A.</dc:creator>
<dc:creator>Gaddy, J.</dc:creator>
<dc:creator>Nichols, C.</dc:creator>
<dc:creator>Hall, M. H.</dc:creator>
<dc:creator>Varela, H. N.</dc:creator>
<dc:creator>Carlin, S. M.</dc:creator>
<dc:creator>Hillebrand, G. H.</dc:creator>
<dc:creator>Giacobe, E. J.</dc:creator>
<dc:creator>Aronoff, D. M.</dc:creator>
<dc:creator>Hooven, T. A.</dc:creator>
<dc:date>2024-12-07</dc:date>
<dc:identifier>doi:10.1101/2024.12.06.627252</dc:identifier>
<dc:title><![CDATA[A CRISPRi Library Screen in Group B Streptococcus Identifies Surface Immunogenic Protein (Sip) as a Mediator of Multiple Host Interactions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-12-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.12.12.628285v1?rss=1">
<title>
<![CDATA[
Deep homology of a brachyury regulatory syntax and origin of the notochord 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.12.12.628285v1?rss=1</link>
<description><![CDATA[
The brachyury gene encodes a T-box transcription factor (TF) that is crucial for the development of the notochord, a novel trait of chordates1. Brachyury expression in axial mesodermal cells (notochord progenitors) is regarded as a chordate innovation2, yet it remains unclear how the chordate ancestor acquired this expression domain. By examining the sequences of previously identified notochord enhancers of several chordate brachyury genes3-5, we uncovered a regulatory syntax consisting of binding sites for four TFs (Su(H), Foxh1, Zic, and Ets) with a strict order and orientation. We also identified this syntax, here named SFZE, in potential cis-regulatory modules (CRMs) of brachyury orthologs in various non-chordate animals and even in Capsaspora, a close unicellular relative to animals. Reporter assays demonstrated that SFZE-containing CRMs from non-chordate organisms exhibited regulatory activity in the zebrafish notochord, and mutagenesis of the TF sites reduced the activity. Furthermore, the SFZE syntax in sea urchin confers its endoderm activity, with the TF sites functionally decoupled during gastrulation. These findings indicate that the association of the SFZE syntax with brachyury is ancient, likely predating the origin of animals. The emergence of axial brachyury expression is therefore probably not the result of a newly acquired notochord enhancer, but is instead likely attributed to co-option of upstream signals acting on the conserved SFZE syntax, which facilitates the origin of the notochord from rudimentary endodermal cells.
]]></description>
<dc:creator>Fan, T.-P.</dc:creator>
<dc:creator>Lee, J.-R.</dc:creator>
<dc:creator>Lin, C.-Y.</dc:creator>
<dc:creator>Chen, Y.-C.</dc:creator>
<dc:creator>Cutting, A. E.</dc:creator>
<dc:creator>Cameron, R. A.</dc:creator>
<dc:creator>Yu, J.-K.</dc:creator>
<dc:creator>Su, Y.-H.</dc:creator>
<dc:date>2024-12-13</dc:date>
<dc:identifier>doi:10.1101/2024.12.12.628285</dc:identifier>
<dc:title><![CDATA[Deep homology of a brachyury regulatory syntax and origin of the notochord]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-12-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.12.17.629042v1?rss=1">
<title>
<![CDATA[
Predictive Modeling of Gene Expression and Localization of DNA Binding Site Using Deep Convolutional Neural Networks 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.12.17.629042v1?rss=1</link>
<description><![CDATA[
Despite the sequencing revolution, large swaths of the genomes sequenced to date lack any information about the arrangement of transcription factor binding sites on regulatory DNA. Massively Parallel Reporter Assays (MPRAs) have the potential to dramatically accelerate our genomic annotations by making it possible to measure the gene expression levels driven by thousands of mutational variants of a regulatory region. However, the interpretation of such data often assumes that each base pair in a regulatory sequence contributes independently to gene expression. To enable the analysis of this data in a manner that accounts for possible correlations between distant bases along a regulatory sequence, we developed the Deep learning Adaptable Regulatory Sequence Identifier (DARSI). This convolutional neural network leverages MPRA data to predict gene expression levels directly from raw regulatory DNA sequences. By harnessing this predictive capacity, DARSI systematically identifies transcription factor binding sites within regulatory regions at single-base pair resolution. To validate its predictions, we benchmarked DARSI against curated databases, confirming its accuracy in predicting transcription factor binding sites. Additionally, DARSI predicted novel unmapped binding sites, paving the way for future experimental efforts to confirm the existence of these binding sites and to identify the transcription factors that target those sites. Thus, by automating and improving the annotation of regulatory regions, DARSI generates experimentally actionable predictions that can feed iterations of the theory-experiment cycle aimed at reaching a predictive understanding of transcriptional control.
]]></description>
<dc:creator>Karshenas, A.</dc:creator>
<dc:creator>Roschinger, T.</dc:creator>
<dc:creator>Garcia, H.</dc:creator>
<dc:date>2024-12-20</dc:date>
<dc:identifier>doi:10.1101/2024.12.17.629042</dc:identifier>
<dc:title><![CDATA[Predictive Modeling of Gene Expression and Localization of DNA Binding Site Using Deep Convolutional Neural Networks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-12-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.12.18.629299v1?rss=1">
<title>
<![CDATA[
The clumped isotope signatures of multiple methanogenesis metabolisms 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.12.18.629299v1?rss=1</link>
<description><![CDATA[
Methane is a potent greenhouse gas, an important energy source, and a potential biosignature on extraterrestrial planetary bodies. The relative abundances of doubly substituted ("clumped") methane isotopologues (13CH3D and 12CH2D2) offer important information on the sources and sinks of methane. However, the clumped isotope signatures of microbially produced methane from different methanogenic pathways lack a systematic investigation. In this study, we provide a dataset encompassing the relative isotopologue abundances produced by hydrogenotrophic, methylotrophic, acetoclastic, and methoxydotrophic methanogenesis. We find that a statistical "combinatorial effect" generates significant differences in 12CH2D2 compositions between hydrogenotrophic methanogenesis and other pathways. The thermodynamic drive of methanogenic reactions and phylogenetic affiliation may also influence the isotope compositions of methane. Our study provides new experimental constraints on the isotope signatures of different microbial methanogenic pathways, and evidence of the mechanisms responsible for the observed differences.

TeaserA novel stable isotope tool to track and differentiate sources of biological methane.
]]></description>
<dc:creator>Li, J.</dc:creator>
<dc:creator>Ash, J. L.</dc:creator>
<dc:creator>Cobban, A.</dc:creator>
<dc:creator>Kubik, B. C.</dc:creator>
<dc:creator>Rizzo, G.</dc:creator>
<dc:creator>Thompson, M.</dc:creator>
<dc:creator>Guibourdenche, L.</dc:creator>
<dc:creator>Berger, S.</dc:creator>
<dc:creator>Morra, K.</dc:creator>
<dc:creator>Lin, Y.</dc:creator>
<dc:creator>Mueller, E. P.</dc:creator>
<dc:creator>Masterson, A. L.</dc:creator>
<dc:creator>Stein, R.</dc:creator>
<dc:creator>Fogel, M.</dc:creator>
<dc:creator>Torres, M. A.</dc:creator>
<dc:creator>Feng, X.</dc:creator>
<dc:creator>Holden, J. F.</dc:creator>
<dc:creator>Martini, A.</dc:creator>
<dc:creator>Welte, C.</dc:creator>
<dc:creator>Jetten, M. S. M.</dc:creator>
<dc:creator>Young, E. D.</dc:creator>
<dc:creator>Leavitt, W. D.</dc:creator>
<dc:date>2024-12-20</dc:date>
<dc:identifier>doi:10.1101/2024.12.18.629299</dc:identifier>
<dc:title><![CDATA[The clumped isotope signatures of multiple methanogenesis metabolisms]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-12-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.12.18.629251v1?rss=1">
<title>
<![CDATA[
The gut microbiome promotes mitochondrial respiration in the brain of a Parkinson's disease mouse model 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.12.18.629251v1?rss=1</link>
<description><![CDATA[
The pathophysiology of Parkinsons disease (PD) involves gene-environment interactions that impair various cellular processes such as autophagy, lysosomal function, or mitochondrial dysfunction. Specifically, mitochondria-associated gene mutations increase PD risk, mitochondrial respiration is altered in the PD brain, and mitochondrial-damaging toxins cause PD-like motor and gastrointestinal symptoms in animal models. The gut microbiome is altered in PD patients and represents an environmental risk, however a relationship between mitochondrial function and the microbiome in PD has not been previously established. Herein, we report that striatal mitochondria are functionally overactive in -synuclein-overexpressing (ASO) mice, a model of PD, and that microbiome depletion restores respiration and mitochondria-associated gene expression patterns to wild-type levels. ASO mice harboring a complex microbiome produce increased reactive oxygen species in the striatum whereas germ-free counterparts express elevated levels of antioxidant proteins that may buffer against oxidative damage. Indeed, antioxidant treatment improves motor performance in ASO mice and, remarkably, blocking oxidant scavenging in germ-free mice induces -synuclein-dependent motor deficits. Thus, the gut microbiome increases mitochondrial respiration and oxidative stress in the brain, which enhances motor symptoms in a mouse model of PD.
]]></description>
<dc:creator>Morais, L. H.</dc:creator>
<dc:creator>Stiles, L.</dc:creator>
<dc:creator>Freeman, M.</dc:creator>
<dc:creator>Oguienko, A. D.</dc:creator>
<dc:creator>Hoang, J. D.</dc:creator>
<dc:creator>Jones, J.</dc:creator>
<dc:creator>Quan, B.</dc:creator>
<dc:creator>Devine, J.</dc:creator>
<dc:creator>Bois, J. S.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Trinh, J.</dc:creator>
<dc:creator>Picard, M.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:creator>Mazmanian, S. K.</dc:creator>
<dc:date>2024-12-21</dc:date>
<dc:identifier>doi:10.1101/2024.12.18.629251</dc:identifier>
<dc:title><![CDATA[The gut microbiome promotes mitochondrial respiration in the brain of a Parkinson's disease mouse model]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-12-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.12.20.629847v1?rss=1">
<title>
<![CDATA[
Protein CREATE enables closed-loop design of de novo synthetic protein binders 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.12.20.629847v1?rss=1</link>
<description><![CDATA[
Proteins have proven to be useful agents in a variety of fields, from serving as potent therapeutics to enabling complex catalysis for chemical manufacture. However, they remain difficult to design and are instead typically selected for using extensive screens or directed evolution. Recent developments in protein large language models have enabled fast generation of diverse protein sequences in unexplored regions of protein space predicted to fold into varied structures, bind relevant targets, and catalyze novel reactions. Nevertheless, we lack methods to characterize these proteins experimentally at scale and update generative models based on those results. We describe Protein CREATE (Computational Redesign via an Experiment-Augmented Training Engine), an integrated computational and experimental pipeline that incorporates an experimental workflow leveraging next generation sequencing and phage display with single-molecule readouts to collect vast amounts of quantitative binding data for updating protein large language models. We use Protein CREATE to generate and assay thousands of designed binders to IL-7 receptor  and insulin receptor with parallel positive and negative selections to identify on-target binders. We discover not only individual novel binders but also features of ligand-receptor binding, including preservation of the IL7R - ligand hydrophobic interface specifically and existence of multiple approaches to contact the insulin receptor. We also demonstrate the importance of structural features, such as the lack of unpaired cysteine residues, toward design fidelity and find computational pre-screening metrics, such as interchain predicted TM scoring (iPTM), while useful, are imperfect predictors as they neither guarantee experimental binding nor rule it out. We use the data collected from Protein CREATE to score designs from the initial generative models. Globally, Protein CREATE will power future closed-loop design-build-test cycles to enable fine-grained design of protein binders.
]]></description>
<dc:creator>Lourenco, A. L.</dc:creator>
<dc:creator>Subramanian, A. M.</dc:creator>
<dc:creator>Spencer, R. K.</dc:creator>
<dc:creator>Miao, J.</dc:creator>
<dc:creator>Anaya, M.</dc:creator>
<dc:creator>Fu, W.</dc:creator>
<dc:creator>Chow, E. D.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2024-12-22</dc:date>
<dc:identifier>doi:10.1101/2024.12.20.629847</dc:identifier>
<dc:title><![CDATA[Protein CREATE enables closed-loop design of de novo synthetic protein binders]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-12-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2024.12.22.629782v1?rss=1">
<title>
<![CDATA[
Acoustic tumor paint for real-time imaging, surgical guidance and recurrence monitoring of brain tumors with ultrasound 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2024.12.22.629782v1?rss=1</link>
<description><![CDATA[
The rapid growth, invasiveness, and resistance to treatment of glioblastoma multiforme (GBM) underscore the urgent need for improved diagnostics and therapies. Current surgical practice is limited by challenges with intraoperative imaging, while recurrence monitoring requires expensive magnetic resonance or nuclear imaging scans. Here we introduce "acoustic tumor paint", an approach to labeling brain tumors for ultrasound imaging - a widely accessible imaging modality. We show that gas vesicles (GVs), natural air-filled protein nanostructures, preferentially accumulate in brain tumors following systemic administration in syngeneic and xenograft mouse models of GBM. This enables real-time tumor visualization during surgery and postoperative monitoring of recurrence. We characterize GV uptake and breakdown by tumors and their resident cells and support clinical translatability by documenting non-toxic repeated administration. We also demonstrate the potential for post-operative monitoring in humans by imaging GVs through a human skull and an FDA-approved skull prosthesis. Acoustic tumor paint has the potential to enhance diagnostic accuracy, improve surgical outcomes, make monitoring more accessible, and extend survival in GBM patients.
]]></description>
<dc:creator>Rabut, C.</dc:creator>
<dc:creator>Daghlian, G. H.</dc:creator>
<dc:creator>Barturen-Larrea, P.</dc:creator>
<dc:creator>Li, H. R.</dc:creator>
<dc:creator>Vorder Bruegge, R.</dc:creator>
<dc:creator>Jones, R. M.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Pinton, G. F.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2024-12-22</dc:date>
<dc:identifier>doi:10.1101/2024.12.22.629782</dc:identifier>
<dc:title><![CDATA[Acoustic tumor paint for real-time imaging, surgical guidance and recurrence monitoring of brain tumors with ultrasound]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-12-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.02.631102v1?rss=1">
<title>
<![CDATA[
Reducing Cofilin dosage makes embryos resilient to heat stress 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.02.631102v1?rss=1</link>
<description><![CDATA[
In addition to regulating the actin cytoskeleton, Cofilin also senses and responds to environmental stress. Cofilin can promote cell survival or death depending on context. Yet, many aspects of Cofilins role in survival need clarification. Here, we show that exposing early Drosophila embryos to mild heat stress (32{degrees}C) induces a Cofilin-mediated Actin Stress Response and upregulation of heat- and ER-stress response genes. However, these responses do not alleviate the negative impacts of heat exposure. Instead, heat stressed embryos show downregulation of hundreds of developmental genes, including determinants of the embryonic body plan, and are less likely to hatch as larvae and adults. Remarkably, reducing Cofilin dosage blunts induction of all stress response pathways, mitigates downregulation of developmental genes, and completely rescues survival. Thus, Cofilin intersects with multiple stress response pathways, and modulates the transcriptomic response to heat stress. Strikingly, Cofilin knockdown emerges as a potent pro-survival manipulation for embryos.
]]></description>
<dc:creator>Biel, N.</dc:creator>
<dc:creator>Rashid, F.</dc:creator>
<dc:creator>Natua, S.</dc:creator>
<dc:creator>Wang, T.-Y.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Nguyen, T. V. P.</dc:creator>
<dc:creator>Golding, I.</dc:creator>
<dc:creator>Kalsotra, A.</dc:creator>
<dc:creator>Sokac, A. M.</dc:creator>
<dc:date>2025-01-03</dc:date>
<dc:identifier>doi:10.1101/2025.01.02.631102</dc:identifier>
<dc:title><![CDATA[Reducing Cofilin dosage makes embryos resilient to heat stress]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.02.631145v1?rss=1">
<title>
<![CDATA[
Cross-reactive sarbecovirus antibodies induced by mosaic RBD-nanoparticles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.02.631145v1?rss=1</link>
<description><![CDATA[
Broad immune responses are needed to mitigate viral evolution and escape. To induce antibodies against conserved receptor-binding domain (RBD) regions of SARS-like betacoronavirus (sarbecovirus) spike proteins that recognize SARS-CoV-2 variants of concern and zoonotic sarbecoviruses, we developed mosaic-8b RBD-nanoparticles presenting eight sarbecovirus RBDs arranged randomly on a 60-mer nanoparticle. Mosaic-8b immunizations protected animals from challenges from viruses whose RBDs were matched or mismatched to those on nanoparticles. Here, we describe neutralizing mAbs isolated from mosaic-8b-immunized rabbits, some on par with Pemgarda, the only currently FDA-approved therapeutic mAb. Deep mutational scanning, in vitro selection of spike resistance mutations, and single-particle cryo-electron microscopy structures of spike-antibody complexes demonstrated targeting of conserved RBD epitopes. Rabbit mAbs included critical D-gene segment RBD-recognizing features in common with human anti-RBD mAbs, despite rabbit genomes lacking an equivalent human D-gene segment, thus demonstrating that the immune systems of humans and other mammals can utilize different antibody gene segments to arrive at similar modes of antigen recognition. These results suggest that animal models can be used to elicit anti-RBD mAbs with similar properties to those raised in humans, which can then be humanized for therapeutic use, and that mosaic RBD-nanoparticle immunization coupled with multiplexed screening represents an efficient way to generate and select broadly cross-reactive therapeutic pan-sarbecovirus and pan-SARS-CoV-2 variant mAbs.

Significance StatementSARS-CoV-2 variants and potential zoonotic sarbecovirus infections continue to threaten human health. Anti-SARS-CoV-2 mAbs that recognize conserved epitopes could be used prophylactically or therapeutically. We present approaches to elicit and identify cross-reactive mAbs using immunizations in animals with mosaic RBD-nanoparticles. We show that human and other mammalian immune systems can utilize different antibody gene segments to arrive at similar modes of antigen recognition, underscoring the flexibility of mammalian antibody repertoires and suggesting that experimental animals can be used to generate therapeutically-useful cross-reactive anti-RBD mAbs. The combination of mosaic-8b RBD-nanoparticles to focus the immune response and a multiplexed assay to select cross-reactive mAbs can be applied at larger scale, or against other pathogens, to identify mAbs of therapeutic and scientific potential.
]]></description>
<dc:creator>Fan, C.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>Malecek, K. E.</dc:creator>
<dc:creator>Cohen, A. A.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Baharani, V. A.</dc:creator>
<dc:creator>Rorick, A. V.</dc:creator>
<dc:creator>Gao, H.</dc:creator>
<dc:creator>Gnanapragasam, P. N. P.</dc:creator>
<dc:creator>Rho, S.</dc:creator>
<dc:creator>Alvarez, J.</dc:creator>
<dc:creator>Segovia, L. N.</dc:creator>
<dc:creator>Hatziioannou, T.</dc:creator>
<dc:creator>Bieniasz, P. D.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2025-01-03</dc:date>
<dc:identifier>doi:10.1101/2025.01.02.631145</dc:identifier>
<dc:title><![CDATA[Cross-reactive sarbecovirus antibodies induced by mosaic RBD-nanoparticles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.06.631283v1?rss=1">
<title>
<![CDATA[
Optimizing the Efficacy of Vaccine-Induced Immunotherapy in Melanomas 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.06.631283v1?rss=1</link>
<description><![CDATA[
Cancer therapeutic vaccines are used to strengthen a patients own immune system by amplifying existing immune responses. Intralesional administration of the bacteria-based emm55 vaccine together with the PD1 checkpoint inhibitor produced a strong anti-tumor effect against the B16 melanoma murine model. However, it is not trivial to design an optimal order and frequency of injections for combination therapies. Here, we developed a coupled ordinary differential equations model calibrated to experimental data and used the mesh adaptive direct search method to optimize the treatment protocols of the emm55 vaccine and anti-PD1 combined therapy. This method determined that early consecutive vaccine injections combined with distributed anti-PD1 injections of decreasing separation time yielded the best tumor size reduction. The optimized protocols led to a twofold decrease in tumor area for the vaccine-alone treatment, and a fourfold decrease for the combined therapy. Our results reveal the tumor subpopulation dynamics in the optimal treatment condition, defining the path for efficacious treatment design. Similar computational frameworks can be applied to other tumors and other combination therapies to generate experimentally testable hypotheses in a fairly unrestricted and inexpensive setting.
]]></description>
<dc:creator>Chamseddine, I.</dc:creator>
<dc:creator>Kambara, M.</dc:creator>
<dc:creator>Bhatt, P.</dc:creator>
<dc:creator>Pilon-Thomas, S.</dc:creator>
<dc:creator>Rejniak, K. A.</dc:creator>
<dc:date>2025-01-08</dc:date>
<dc:identifier>doi:10.1101/2025.01.06.631283</dc:identifier>
<dc:title><![CDATA[Optimizing the Efficacy of Vaccine-Induced Immunotherapy in Melanomas]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.06.631539v1?rss=1">
<title>
<![CDATA[
Characterization and automated classification of sentences in the biomedical literature: a case study for biocuration of gene expression and protein kinase activity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.06.631539v1?rss=1</link>
<description><![CDATA[
Biological knowledgebases are essential resources for biomedical researchers, providing ready access to gene function and genomic data. Professional, manual curation of knowledgebases, however, is labor-intensive and thus high-performing machine learning methods that improve biocuration efficiency are needed. Here we report on sentence-level classification to identify biocuration-relevant sentences in the full text of published references for two gene function data types: gene expression and protein kinase activity. We performed a detailed characterization of sentences from references in the WormBase bibliography and used this characterization to define three tasks for classifying sentences as either 1) fully curatable, 2) fully and partially curatable, or 3) all language-related. We evaluated various machine learning (ML) models applied to these tasks and found that GPT and BioBERT achieve the highest average performance, resulting in F1 performance scores ranging from 0.89 to 0.99 depending upon the task. Our findings demonstrate the feasibility of extracting biocuration-relevant sentences from full text. Integrating these models into professional biocuration workflows, such as those used by the Alliance of Genome Resources and the ACKnowledge community curation platform, might well facilitate efficient and accurate annotation of the biomedical literature.
]]></description>
<dc:creator>Raciti, D.</dc:creator>
<dc:creator>Van Auken, K.</dc:creator>
<dc:creator>Arnaboldi, V.</dc:creator>
<dc:creator>Tabone, C. J.</dc:creator>
<dc:creator>Muller, H.-M.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2025-01-08</dc:date>
<dc:identifier>doi:10.1101/2025.01.06.631539</dc:identifier>
<dc:title><![CDATA[Characterization and automated classification of sentences in the biomedical literature: a case study for biocuration of gene expression and protein kinase activity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.08.632013v1?rss=1">
<title>
<![CDATA[
Design and characterization of HIV-1 vaccine candidates to elicit antibodies targeting multiple epitopes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.08.632013v1?rss=1</link>
<description><![CDATA[
A primary goal in the development of an AIDS vaccine is the elicitation of broadly neutralizing antibodies (bNAbs) that protect against diverse HIV-1 strains. To this aim, germline-targeting immunogens have been developed to activate bNAb precursors and initiate the induction of bNAbs. While most pre-clinical germline-targeting HIV-1 vaccine candidates only include a single bNAb precursor epitope, an effective HIV-1 vaccine will likely require bNAbs that target multiple epitopes on Env. Here, we report a newly designed germline-targeting Env SOSIP trimer, named 3nv.2, that presents three bNAb epitopes on Env: the CD4bs, V3, and V2 epitopes. 3nv.2 forms a stable trimeric Env and binds to bNAb precursors from each of the desired epitopes. Immunization experiments in rhesus macaques and mice demonstrate 3nv.2 elicits the combined effects of its parent immunogens. Our results provide proof-of-concept for using a germline-targeting immunogen presenting three or more bNAb epitopes and a framework to develop improved next-generation HIV-1 vaccine candidates.
]]></description>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>Hartweger, H.</dc:creator>
<dc:creator>Nishimura, Y.</dc:creator>
<dc:creator>Gavor, E.</dc:creator>
<dc:creator>Nagashima, K.</dc:creator>
<dc:creator>Koranda, N. S.</dc:creator>
<dc:creator>Gnanapragasam, P. N. P.</dc:creator>
<dc:creator>Kakutani, L. M.</dc:creator>
<dc:creator>Segovia, L.</dc:creator>
<dc:creator>Donau, O.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Martin, M. A.</dc:creator>
<dc:creator>Nussenzweig, M. C.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2025-01-09</dc:date>
<dc:identifier>doi:10.1101/2025.01.08.632013</dc:identifier>
<dc:title><![CDATA[Design and characterization of HIV-1 vaccine candidates to elicit antibodies targeting multiple epitopes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.09.632278v1?rss=1">
<title>
<![CDATA[
Genomes of the entomopathogenic nematode Steinernema hermaphroditum and its associated bacteria 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.09.632278v1?rss=1</link>
<description><![CDATA[
As an entomopathogenic nematode (EPN), Steinernema hermaphroditum parasitizes insect hosts and harbors symbiotic Xenorhabdus griffinae bacteria. In contrast to other Steinernematids, S. hermaphroditum has hermaphroditic genetics, offering the experimental scope found in Caenorhabditis elegans. To enable biological analysis of S. hermaphroditum, we have assembled and analyzed its reference genome. This genome assembly has five chromosomal scaffolds and 83 unassigned scaffolds totaling 90.7 Mb, with 19,426 protein-coding genes having a BUSCO completeness of 88.0%. Its autosomes show higher densities of strongly conserved genes in their centers, as in C. elegans, but repetitive elements are evenly distributed along all chromosomes, rather than with higher arm densities as in C. elegans. Either when comparing protein motif frequencies between nematode species or when analyzing gene family expansions during nematode evolution, we observed two categories of genes preferentially associated with the origin of Steinernema or S. hermaphroditum: orthologs of venom genes in S. carpocapsae or S. feltiae; and some types of chemosensory G protein-coupled receptors, despite the tendency of parasitic nematodes to have reduced numbers of chemosensory genes. Three-quarters of venom orthologs occurred in gene clusters, with the larger clusters comprising functionally diverse pathogenicity islands rather than paralogous repeats of a single venom gene. While assembling the genome of S. hermaphroditum, we coassembled bacterial genomes, finding sequence data for not only the known symbiont, X. griffinae, but also for eight other bacterial genera. All eight genera have previously been observed to be associated with Steinernema species or the EPN Heterorhabditis, and may constitute a "second bacterial circle" of EPNs. The genome assemblies of S. hermaphroditum and its associated bacteria will enable use of these organisms as a model system for both entomopathogenicity and symbiosis.
]]></description>
<dc:creator>Schwarz, E. M.</dc:creator>
<dc:creator>Baniya, A.</dc:creator>
<dc:creator>Heppert, J. K.</dc:creator>
<dc:creator>Schwartz, H. T.</dc:creator>
<dc:creator>Tan, C.-H.</dc:creator>
<dc:creator>Antoshechkin, I.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Goodrich-Blair, H.</dc:creator>
<dc:creator>Dillman, A. R.</dc:creator>
<dc:date>2025-01-12</dc:date>
<dc:identifier>doi:10.1101/2025.01.09.632278</dc:identifier>
<dc:title><![CDATA[Genomes of the entomopathogenic nematode Steinernema hermaphroditum and its associated bacteria]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.11.632547v1?rss=1">
<title>
<![CDATA[
Systematic characterization of zinc in a series of breast cancer cell lines reveals significant changes in zinc homeostasis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.11.632547v1?rss=1</link>
<description><![CDATA[
An optimal amount of labile zinc (Zn2+) is essential for proliferation of human cells, where Zn2+ levels that are too high or too low cause cell cycle exit. Tumors of the breast have been characterized by high levels of total Zn2+. Given the role of Zn2+ in proliferation of human cells and elevation of zinc in breast cancer tumors, we examined the concentration of total and labile Zn2+ across a panel of 5 breast cancer cell lines, compared to the normal MCF10A cell line. We found that three cell lines (MDA-MB-231, MDA-MB-157, and SK-Br-3) showed elevated labile Zn2+ in the cytosol, while T-47D showed significantly lower Zn2+, and MCF7 showed no change compared to MCF10A cells. There was no change in total Zn2+ across the cell lines, as measured by ICP-MS, but we did observe a difference in the cells ability to accumulate Zn2+ when Zn2+ in the media was elevated. Therefore, we examined how proliferation of each cell line was affected by increases and decreases in the media. We found striking differences, where three cancer cell lines (MDA-MB-231, MDA-MB-157, and MCF7) showed robust proliferation in high Zn2+ at concentrations that killed MCF10A, T-47D, and SK-Br-3 cells. We also discovered that 4 of the 5 cancer cell lines demonstrate compromised proliferation and increased cell death in low Zn2+, suggesting these cells may be addicted to Zn2+. Overall, our study suggests significant differences in Zn2+ homeostasis and regulation in different types of breast cancer cells, with consequences for both proliferation and cell viability.
]]></description>
<dc:creator>Woyciehowsky, M.</dc:creator>
<dc:creator>Larson, P.</dc:creator>
<dc:creator>Stephan, A. R.</dc:creator>
<dc:creator>Dandridge, S. L.</dc:creator>
<dc:creator>Idonije, D.</dc:creator>
<dc:creator>Berg, K. A.</dc:creator>
<dc:creator>Lanthier, A.</dc:creator>
<dc:creator>Araiza Acuna, S.</dc:creator>
<dc:creator>Stites, S. W.</dc:creator>
<dc:creator>Gebhardt, W. J.</dc:creator>
<dc:creator>Holtzen, S. E.</dc:creator>
<dc:creator>Rakshit, A.</dc:creator>
<dc:creator>Palmer, A. E.</dc:creator>
<dc:date>2025-01-13</dc:date>
<dc:identifier>doi:10.1101/2025.01.11.632547</dc:identifier>
<dc:title><![CDATA[Systematic characterization of zinc in a series of breast cancer cell lines reveals significant changes in zinc homeostasis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.20.633972v1?rss=1">
<title>
<![CDATA[
Two stages of substrate discrimination dictate selectivity in the E. coli MetNI-Q ABC transporter system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.20.633972v1?rss=1</link>
<description><![CDATA[
The Escherichia coli MetNI-Q importer, an ATP-binding cassette (ABC) transporter, mediates the uptake of both L- and D-enantiomers of methionine. Original in vivo uptake studies show a strong preference for L-Met over D-Met, but the molecular basis of this selectivity is unclear. In this work, we systematically examine substrate discrimination by the MetNI transporter and MetQ substrate binding protein using an array of biophysical and biochemical techniques. Based on the kinetic and thermodynamic parameters of individual intermediates in the transport cycle, we uncover multiple steps in the transport cycle that confer substrate specificity. As in many other ABC importer systems, selectivity is applied at the level of binding to the substrate binding protein: MetQ dictates a 1,000-fold preference for L-Met over D-Met. However, beyond this initial level of selectivity, MetQ displays distinct binding preferences for the MetNI transporter depending on the substrate. We propose that the differences in binding affinities reflect the more favored release of L-Met into the permeation pathway when compared to D-Met. In support of this model, under saturating conditions, MetNI transports L-Met across the lipid bilayer at a faster rate than D-Met. Interestingly, the ATPase activity of the MetNI-Q complex is not modulated by the presence of substrate. Our studies reveal that the MetNI-Q system incorporates two separate steps in tuning methionine uptake to substrate chirality and availability. This method of discrimination ensures the import of the most biologically preferred substrate while also allowing for adaptability to more limiting nutrient conditions.
]]></description>
<dc:creator>Yang, J. G.</dc:creator>
<dc:creator>Chen, H. Y.</dc:creator>
<dc:creator>Guardado, J. H.</dc:creator>
<dc:creator>Gardner, M.</dc:creator>
<dc:creator>Foronda, M. S.</dc:creator>
<dc:date>2025-01-21</dc:date>
<dc:identifier>doi:10.1101/2025.01.20.633972</dc:identifier>
<dc:title><![CDATA[Two stages of substrate discrimination dictate selectivity in the E. coli MetNI-Q ABC transporter system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.17.633600v1?rss=1">
<title>
<![CDATA[
Recruiting ESCRT to single-chain heterotrimer peptide-MHCI releases antigen-presenting vesicles that stimulate T cells selectively 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.17.633600v1?rss=1</link>
<description><![CDATA[
Immune cells naturally secrete extracellular antigen-presenting vesicles (APVs) displaying peptide:MHC complexes to facilitate the initiation, expansion, maintenance, or silencing of immune responses. Previous work has sought to manufacture and purify these vesicles for cell-free immunotherapies. In this study, APV assembly and release is achieved in non-immune cells by transfecting HEK293T or Expi293F cells with a single-chain heterotrimer (SCT) peptide/major histocompatibility complex I (pMHCI) construct containing an ESCRT- and ALIX-binding region (EABR) sequence appended to the cytoplasmic tail; this EABR sequence recruits ESCRT proteins to induce the budding of APVs displaying SCT pMHCI. A comparison of multiple pMHCI constructs shows that inducing the release of APVs by the addition of an EABR sequence generalizes across SCT pMHCI constructs. Purified pMHCI/EABR APVs selectively stimulate IFN-{gamma} release from T cells presenting their cognate T cell receptor, demonstrating the potential use of these vesicles as a form of cell-free immunotherapy.

Significance StatementImmune cells are known to naturally release pMHC-displaying extracellular vesicles (EVs), called antigen-presenting vesicles (APVs), which can orchestrate immune responses either directly or with the aid of antigen-presenting cells (APCs). For decades, researchers have pursued ways to replicate these APVs for immunotherapy by using chemically modified nanoparticles or by engineering the increased expression of APVs from immune cells which are typically low yield. Here we presents a broadly applicable platform for generating high concentrations of pMHCI-displaying APVs that can selectively modulate T cells, demonstrating a significant advance in the engineering of APVs for cell-free immunotherapy. The APVs presented here, and related APVs, could be translated into clinical therapies for modulating cancer progression or regulating autoimmunity in addition to their use as a tool to help characterize how endogenous extracellular vesicles influence the immune system.
]]></description>
<dc:creator>Olson, B. A.</dc:creator>
<dc:creator>Huey-Tubman, K. E.</dc:creator>
<dc:creator>Mao, Z.</dc:creator>
<dc:creator>Hoffmann, M. A. G.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:creator>Mayo, S. L.</dc:creator>
<dc:date>2025-01-22</dc:date>
<dc:identifier>doi:10.1101/2025.01.17.633600</dc:identifier>
<dc:title><![CDATA[Recruiting ESCRT to single-chain heterotrimer peptide-MHCI releases antigen-presenting vesicles that stimulate T cells selectively]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.21.633868v1?rss=1">
<title>
<![CDATA[
Unveiling Hidden Microbial Diversity in Mars2020 Mission Assembly Cleanrooms withMolecular Insights into the Persistent andPerseverance of Novel Species DefyingMetagenome Sequencing 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.21.633868v1?rss=1</link>
<description><![CDATA[
NASA cleanrooms, where space mission components are assembled, maintain stringent cleaning protocols and nutrient-poor environments, resulting in low yet persistent microbial loads. Although these oligotrophic extremophiles are reported in small numbers, their resistance to environmental stresses, sparse presence, and difficulty in extracting biomolecules often lead to their omission, even with advanced sequencing technologies. Traditional metagenomic approaches fail to detect these rare species due to challenges in lysing robust microbial cells and isolating minute amounts of DNA from dominant microorganisms. Additionally, the absence of database references for novel extremophiles limits their identification. Over a six month period of monitoring Mars 2020 mission cleanrooms, 182 bacterial strains from 19 families were identified using advanced molecular techniques. This included 14 novel Gram-positive species, eight of which were spore-formers. Despite being present at only about 0.001% abundance in metagenomic sequencing data, they were successfully cultured. Functional studies revealed their capabilities in nitrogen cycling, carbohydrate metabolism, and radiation resistance. Furthermore, 12 biosynthetic gene clusters, including those linked to ectoine and{varepsilon} -poly-L-lysine production, underscore their biotechnological potential. These findings emphasize the hidden microbial diversity in spacecraft assembly cleanrooms and highlight the need for advanced detection methods to uncover extremophiles with potential applications in biotechnology and space exploration.

SynopsisUnderstanding extremophiles in NASA spacecraft assembly cleanrooms aids contaminant management in confined habitats, ensuring sustainability and safety in future space missions.
]]></description>
<dc:creator>Muthamilselvi Sivabalan, S. K.</dc:creator>
<dc:creator>Vijayakumar, V.</dc:creator>
<dc:creator>Sengupta, P.</dc:creator>
<dc:creator>Palmal, S.</dc:creator>
<dc:creator>Krishnamurthi, S.</dc:creator>
<dc:creator>Kumar Singh, N.</dc:creator>
<dc:creator>Kyrpides, N. C.</dc:creator>
<dc:creator>Raman, K.</dc:creator>
<dc:creator>Venkateswaran, K.</dc:creator>
<dc:date>2025-01-24</dc:date>
<dc:identifier>doi:10.1101/2025.01.21.633868</dc:identifier>
<dc:title><![CDATA[Unveiling Hidden Microbial Diversity in Mars2020 Mission Assembly Cleanrooms withMolecular Insights into the Persistent andPerseverance of Novel Species DefyingMetagenome Sequencing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.21.634156v1?rss=1">
<title>
<![CDATA[
Auto-methylation of the histone methyltransferase SetDB1 at its histone-mimic motifs ensures the spreading and maintenance of heterochromatin 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.21.634156v1?rss=1</link>
<description><![CDATA[
Heterochromatin plays a critical role in nuclear organization and the regulation of gene expression by directing 3D genome organization, regulating lineage-specific gene expression, and ensuring the repression of transposable elements and endogenous retroviruses. Functionally and structurally distinct chromatin domains are defined by the so-called histone code, which consists of combinations of post-translational histone modifications deposited by "code writers" and recognized by "code readers." The primary mark of heterochromatin, trimethylation of histone H3 at lysine 9 (H3K9me3), is deposited by histone methyltransferases, such as SetDB1, and serves as a binding platform for readers, most notably HP1 family proteins.

Using a reporter system to monitor the dynamics of heterochromatin establishment and maintenance, we demonstrated that transient tethering of HP1 triggers the SetDB1-dependent establishment of stable heterochromatin. This finding indicates the presence of a feedback mechanism wherein the reader of the H3K9me3 mark recruits the writer. We further discovered that the genetic interaction between SetDB1 and HP1 is mirrored by a direct physical interaction. This interaction requires the auto-methylation of two conserved histone mimic motifs located in unstructured regions of SetDB1. HP1 binds these SetDB1 motifs using the same molecular interface it employs to recognize the modified histone tail.

Our findings show that SetDB1 auto-methylation is essential for the spreading and stable maintenance of heterochromatin. This includes its roles in processes such as X-chromosome inactivation and the negative feedback regulation of a large gene family encoding KRAB-ZNF transcriptional repressors. Thus, the primary heterochromatin mark is not limited to nucleosomes but is also deployed on the marks writer itself. This fosters a direct physical interaction between the writer and the reader, ensuring key features of heterochromatin: its spreading to establish extended domains and its stable maintenance through cell divisions.
]]></description>
<dc:creator>Tang, Q.</dc:creator>
<dc:creator>Zhang, A.</dc:creator>
<dc:creator>Sullivan, M.</dc:creator>
<dc:creator>Fejes Toth, K.</dc:creator>
<dc:creator>Aravin, A. A.</dc:creator>
<dc:date>2025-01-24</dc:date>
<dc:identifier>doi:10.1101/2025.01.21.634156</dc:identifier>
<dc:title><![CDATA[Auto-methylation of the histone methyltransferase SetDB1 at its histone-mimic motifs ensures the spreading and maintenance of heterochromatin]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.25.634867v1?rss=1">
<title>
<![CDATA[
Building Foundation Models to Characterize Cellular Interactions via Geometric Self-Supervised Learning on Spatial Genomics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.25.634867v1?rss=1</link>
<description><![CDATA[
Cellular interactions form the fundamental/core circuits that drive development, physiology, and disease within tissues. Advances in spatial genomics (SG) and artificial intelligence (AI) offer unprecedented opportunities to computationally analyze and predict the behavior of cell intricate networks, and to identify interactions that drive disease states. However, challenges arise in both methodology and scalability: (i) how to computationally characterize complicated cellular interactions of multi-scale nature where chemical genes/circuits in individual cells process information and drive interactions among large numbers of diverse cell types, and (ii) how to scale up the pipeline to accommodate the increasing volumes of SG data that map transcriptome-scale gene expression and spatial proximity across millions of cells. In this paper, we introduce the Cellular Interaction Foundation Model (CI-FM), an AI foundation model functioning to analyze and simulate cellular interactions within living tissues. In the CI-FM pipeline, we explicitly capture and embed cellular interactions within microenvironments by leveraging the powerful and scalable geometric graph neural network model, and optimize the characterization of cellular interactions with a novel self-supervised learning objective - we train it to infer gene expressions of cells based upon their interacting microenvironment. As a result, we construct CI-FM with 100 million parameters by consuming SG data of 23 million cells. Our benchmarking experiments show CI-FM effectively infers gene expressions conditional on the microenvironmental contexts: we achieve a high correlation and a low mismatch error (MSE of 1.1% relative to the square median expression), with 79.4% of cells on average being annotated as the similar cell type based on their predicted and actual expressions. We demonstrate the downstream utility of CI-FM by: (i) applying CI-FM to embed tumor samples to capture cellular interactions within tumor microenvironments (ROC-AUC score of 0.76 on classifying sample conditions via linear probing on embeddings), and identifying shared signatures across samples; and (ii) using CI-FM to simulate changes in microenvironmental composition in response to T cell infiltration, which highlights how CI-FM can be leveraged to model cellular responses to tissue perturbations - an essential step toward constructing "AI virtual tissues". Our model is open source and publicly accessible at https://huggingface.co/ynyou/CIFM.
]]></description>
<dc:creator>You, Y.</dc:creator>
<dc:creator>Wang, Z.</dc:creator>
<dc:creator>Fleisher, K.</dc:creator>
<dc:creator>Liu, R.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2025-01-27</dc:date>
<dc:identifier>doi:10.1101/2025.01.25.634867</dc:identifier>
<dc:title><![CDATA[Building Foundation Models to Characterize Cellular Interactions via Geometric Self-Supervised Learning on Spatial Genomics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.27.635147v1?rss=1">
<title>
<![CDATA[
Designing biochemical circuits with tree search 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.27.635147v1?rss=1</link>
<description><![CDATA[
Discovering biochemical circuits that exhibit a desired behavior is an outstanding problem in biological engineering. The traditional approach of enumerating every possible circuit topology becomes intractable for circuits with more than four components due to combinatorial scaling of the search space. Here, we use Monte Carlo Tree Search (MCTS), a reinforcement learning (RL) algorithm, to optimize circuit topology for a target phenotype by approaching circuit design as a sequence of assembly decisions. Our RL-based design framework, which we call CircuiTree, efficiently and comprehensively finds robust designs for three-component oscillators by prioritizing sparsity. CircuiTree can also infer candidate network motifs from its search results, producing similar results to enumeration. Using parallel MCTS, we scale this workflow up to five components and find that highly fault-tolerant designs use a novel strategy, which we call motif multiplexing. Multiplexed circuits contain many overlapping network motifs that each activate in different mutational scenarios. The evolutionary robustness of multiplexing may explain the ubiquity of multiple sub-oscillators in circadian clock circuits. Overall, CircuiTree provides the first scalable computational platform for designing biochemical circuits.
]]></description>
<dc:creator>Bhamidipati, P. S.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2025-01-29</dc:date>
<dc:identifier>doi:10.1101/2025.01.27.635147</dc:identifier>
<dc:title><![CDATA[Designing biochemical circuits with tree search]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.31.635844v1?rss=1">
<title>
<![CDATA[
Plasticity and invariance of Arabidopsis inflorescence and floral shoot apical meristems in response to mineral nutrients 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.31.635844v1?rss=1</link>
<description><![CDATA[
In many species, floral organ production is invariant while flower production rate can be plastic. This allows plants to adapt flower number to their environment whilst maintaining a constant flower structure. The CLAVATA/WUSCHEL feedback loop underpins both inflorescence (IM) and floral meristem (FM) activity, respectively responsible for flower and floral organ production. We explore how plasticity and invariance can differ between IM and FM in response to nutrient availability. FM size is less sensitive to changes in nutrients than IM size, and floral organ production is insensitive to these small size changes. However, clavata3 mutants display larger changes in FM size, approaching those observed in WT IM under nutrient change, with increased floral organ number. This suggests that invariant floral organ production requires that FM size undergoes limited changes in response to nutrients. Compared to the IM, in the FM, levels of cytokinin (CK) signaling are lower and CK signaling and WUSCHEL expression are less impacted by nutrient level. Through genetic perturbations, we show a reduced response of FMs to varying cytokinin levels. Our work shows one way that the balance between plasticity and invariance can be set differently in different contexts.
]]></description>
<dc:creator>Landrein, B.</dc:creator>
<dc:creator>Abley, K.</dc:creator>
<dc:creator>Formosa-Jordan, P.</dc:creator>
<dc:creator>Meyerowitz, E. M.</dc:creator>
<dc:creator>Jonsson, H.</dc:creator>
<dc:creator>Locke, J. C. W.</dc:creator>
<dc:date>2025-01-31</dc:date>
<dc:identifier>doi:10.1101/2025.01.31.635844</dc:identifier>
<dc:title><![CDATA[Plasticity and invariance of Arabidopsis inflorescence and floral shoot apical meristems in response to mineral nutrients]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.01.31.635819v1?rss=1">
<title>
<![CDATA[
FETCH enables fluorescent labeling of membrane proteins in vivo with spatiotemporal control in Drosophila 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.01.31.635819v1?rss=1</link>
<description><![CDATA[
Fluorescent labeling approaches are crucial for elucidating protein function and dynamics. While enhancer trapping in Drosophila has been useful for the characterization of gene transcription, protein-specific visualization in vivo has been more elusive. To overcome these limitations, we developed Fluorescent Endogenous Tagging with a Covalent Hook (FETCH) to label cell surface proteins (CSPs) in vivo through a stable covalent bond mediated by the DogTag-DogCatcher peptide partner system1. FETCH leverages a spontaneous covalent isopeptide bond that forms between the 23-amino acid DogTag and the 15-kDa DogCatcher. Unlike most tags that work best at protein termini, DogTag is optimized for function in protein loops, expanding the range of sites that can be targeted in proteins. In FETCH, DogTag is introduced into extracellular loops of CSPs through genome engineering, enabling covalent bond formation with a genetically encoded DogCatcher-GFP fusion protein that can be secreted from a variety of cell types. We describe a flow cytometry-based platform for the identification of efficient DogTag insertion sites in vitro and demonstrate the ability to visualize both tagged DIP- and Dpr10 in vivo, two immunoglobulin superfamily proteins that facilitate neuronal target recognition at Drosophila neuromuscular junctions and brain synapses. The versatility of FETCH enables fluorescent labeling with precise temporal and spatial control in vivo, enabling applications previously unfeasible.
]]></description>
<dc:creator>Rostam, K. D.</dc:creator>
<dc:creator>Morano, N. C.</dc:creator>
<dc:creator>Menon, K. P.</dc:creator>
<dc:creator>Lopez, D. H.</dc:creator>
<dc:creator>Shapiro, L.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:creator>Feng, S.</dc:creator>
<dc:creator>Mann, R. S.</dc:creator>
<dc:date>2025-02-01</dc:date>
<dc:identifier>doi:10.1101/2025.01.31.635819</dc:identifier>
<dc:title><![CDATA[FETCH enables fluorescent labeling of membrane proteins in vivo with spatiotemporal control in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-02-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.02.01.636063v1?rss=1">
<title>
<![CDATA[
Hookworm genes encoding intestinal excreted-secreted proteins are transcriptionally upregulated in response to the host's immune system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.02.01.636063v1?rss=1</link>
<description><![CDATA[
Hookworms are intestinal parasitic nematodes that chronically infect [~]500 million people, with reinfection common even after clearance by drugs. How infecting hookworms successfully overcome host protective mechanisms is unclear, but it may involve hookworm proteins that digest host tissues, or counteract the hosts immune system, or both. To find such proteins in the zoonotic hookworm Ancylostoma ceylanicum, we identified hookworm genes encoding excreted-secreted (ES) proteins, hookworm genes preferentially expressed in the hookworm intestine, and hookworm genes whose transcription is stimulated by the host immune system. We collected ES proteins from adult hookworms harvested from hamsters; mass spectrometry identified 565 A. ceylanicum genes encoding ES proteins. We also used RNA-seq to identify A. ceylanicum genes expressed both in young adults (12 days post-infection) and in intestinal and non-intestinal tissues dissected from mature adults (19 days post-infection), with hamster hosts that either had normal immune systems or were immunosuppressed by dexamethasone. In adult A. ceylanicum, we observed 1,670 and 1,196 genes with intestine- and non-intestine-biased expression, respectively. Comparing hookworm gene activity in normal versus immunosuppressed hosts, we observed almost no changes of gene activity in 12-day young adults or non-intestinal 19-day adult tissues. However, in intestinal 19-day adult tissues, we observed 1,951 positively immunoregulated genes (upregulated at least two-fold in normal hosts versus immunosuppressed hosts), and 137 genes that were negatively immunoregulated. Thus, immunoregulation was observed primarily in mature adult hookworm intestine directly exposed to host blood; it may include hookworm genes activated in response to the host immune system in order to neutralize the host immune system. We observed 153 ES genes showing positive immunoregulation in 19-day adult intestine; of these genes, 69 had ES gene homologs in the closely related hookworm Ancylostoma caninum, 24 in the human hookworm Necator americanus, and 24 in the more distantly related strongylid parasite Haemonchus contortus. Such a mixture of rapidly evolving and conserved genes could comprise virulence factors enabling infection, provide new targets for drugs or vaccines against hookworm, and aid in developing therapies for autoimmune diseases.
]]></description>
<dc:creator>Schwarz, E. M.</dc:creator>
<dc:creator>Noon, J. B.</dc:creator>
<dc:creator>Chicca, J. D.</dc:creator>
<dc:creator>Garceau, C.</dc:creator>
<dc:creator>Li, H.</dc:creator>
<dc:creator>Antoshechkin, I.</dc:creator>
<dc:creator>Ilik, V.</dc:creator>
<dc:creator>Pafco, B.</dc:creator>
<dc:creator>Weeks, A. M.</dc:creator>
<dc:creator>Homan, E. J.</dc:creator>
<dc:creator>Ostroff, G. R.</dc:creator>
<dc:creator>Aroian, R. V.</dc:creator>
<dc:date>2025-02-03</dc:date>
<dc:identifier>doi:10.1101/2025.02.01.636063</dc:identifier>
<dc:title><![CDATA[Hookworm genes encoding intestinal excreted-secreted proteins are transcriptionally upregulated in response to the host's immune system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-02-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.02.04.636493v1?rss=1">
<title>
<![CDATA[
CryoEM-enabled visual proteomics reveals de novo structures of oligomeric protein complexes from Azotobacter vinelandii 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.02.04.636493v1?rss=1</link>
<description><![CDATA[
Single particle cryoelectron microscopy (cryoEM) and cryoelectron tomography (cryoET) are powerful methods for unveiling unique and functionally relevant structural states. Aided by mass spectrometry and machine learning, they promise to facilitate the visual exploration of proteomes. Leveraging visual proteomics, we interrogate structures isolated from a complex cellular milieu by cryoEM to identify and classify molecular structures and complexes de novo. That approach determines the identity of six distinct oligomeric protein complexes from partially purified extracts of Azotobacter vinelandii using both anaerobic and aerobic cryoEM. Identification of the first unknown species, phosphoglucoisomerase (Pgi1), is achieved by comparing three automated model building programs: CryoID, DeepTracer, and ModelAngelo with or without a priori proteomics data. All three programs identify the Pgi1 protein, revealed to be in a new decameric state, as well as additional globular structures identified as glutamine synthetase (GlnA) and bacterioferritin (Bfr). Large filamentous assemblies are observed in tomograms reconstructed from cryoFIB milled lamellae of nitrogen-fixing A. vinelandii. Enrichment of these species from the cells by centrifugation allows for structure determination of three distinct filament types by helical reconstruction methods: the Type 6 Secretion System non-contractile sheath tube (TssC), a novel filamentous form of the soluble pyridine transhydrogenase (SthA), and the flagellar filament (FliC). The multimeric states of Pgi1 and SthA stand out in contrast to known crystallographic structures and offer a new structural framework from which to evaluate their activities. Overall, by allowing the study of near-native oligomeric protein states, cryoEM-enabled visual proteomics reveals novel structures that correspond to relevant species observed in situ.



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]]></description>
<dc:creator>Warmack, R. A.</dc:creator>
<dc:creator>Maggiolo, A. O.</dc:creator>
<dc:creator>Shen, Y.</dc:creator>
<dc:creator>Zhang, T.</dc:creator>
<dc:date>2025-02-04</dc:date>
<dc:identifier>doi:10.1101/2025.02.04.636493</dc:identifier>
<dc:title><![CDATA[CryoEM-enabled visual proteomics reveals de novo structures of oligomeric protein complexes from Azotobacter vinelandii]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-02-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.02.04.636526v1?rss=1">
<title>
<![CDATA[
Distinct Microbial Communities Within and On Seep Carbonates Support Long-term Anaerobic Oxidation of Methane and Novel pMMO Diversity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.02.04.636526v1?rss=1</link>
<description><![CDATA[
At methane seeps worldwide, syntrophic anaerobic methane-oxidizing archaea and sulfate-reducing bacteria (ANME-SRB) promote carbonate precipitation and rock formation, acting as methane and carbon sink. While maintenance of active anaerobic oxidation of methane (AOM) within seep carbonates has been documented, the ANME-SRB reactivity to methane exposure remains uncertain. Surface-associated microbes may metabolize AOM-derived sulfide, maintain carbonate anoxia, and contribute to carbonate dissolution and higher trophic levels; however, these microbial communities are poorly described thus far. Here we provide new insights into microbial diversity, metabolic potential, activity, and resiliency within and on Southern Californian methane seep carbonates, by combining 16S rRNA and metagenomic sequencing, laboratory incubations, and BONCAT-FISH. Ca. Methanophaga (ANME-1) dominated the carbonate interiors across different seepage activities, based on sequencing, while the dominant SRB was Ca. Desulfaltia, potentially a new ANME partner. BONCAT-FISH revealed differences in ANME-1 cell activity, suggesting cell dormancy or DNA preservation at less active seep sites. Carbonate incubations from low activity seeps ([&ge;]24 months) showed an exponential AOM reactivation (44-day doubling time), suggesting seep carbonates remain potential methane sinks over dynamic seepage conditions. The surface-associated communities were distinct from the carbonate interior and other seep habitats, and highly heterogeneous. Surface ANME-SRB biofilms and sulfide-oxidizing bacterial mats were associated with high and intermediate AOM carbonates, potentially influencing carbonate precipitation/dissolution. Carbonate surfaces shared diverse aerobic methanotrophs with invertebrates, potentially serving as pool for animal epibionts. Besides particulate methane monooxygenases from aerobic methanotrophs, we found divergent forms including within a Methylophagaceae (GCA-002733105) MAG suggesting a new function within Methylophagaceae.
]]></description>
<dc:creator>Mayr, M. J.</dc:creator>
<dc:creator>Parra, S. A.</dc:creator>
<dc:creator>Connon, S. A.</dc:creator>
<dc:creator>Narayanan, A. K.</dc:creator>
<dc:creator>Murali, R.</dc:creator>
<dc:creator>Cremiere, A.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2025-02-08</dc:date>
<dc:identifier>doi:10.1101/2025.02.04.636526</dc:identifier>
<dc:title><![CDATA[Distinct Microbial Communities Within and On Seep Carbonates Support Long-term Anaerobic Oxidation of Methane and Novel pMMO Diversity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-02-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.02.10.637505v1?rss=1">
<title>
<![CDATA[
Molecularly-guided spatial proteomics captures single-cell identity and heterogeneity of the nervous system 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.02.10.637505v1?rss=1</link>
<description><![CDATA[
Single-cell spatial proteomics (scSP) holds substantial potential for profiling healthy and diseased tissues. The emerging method of molecularly-guided unbiased scSP has mostly been applied to peripheral somatic tissues. Here, we optimize and apply scSP to the healthy and diseased mammalian brain, using molecularly-guided laser capture microdissection and unbiased mass spectrometry. We systematically evaluate the effects of tissue fixation, marker staining, and sample input size on proteome coverage and quantitative accuracy. We benchmark this workflow by profiling region-specific neuronal proteomes and describing the response of non-neuronal cells to acute brain injury. Across these applications, we integrate complementary transcriptomic resources to evaluate cross-modality trends and refine neuronal proteomic results by filtering out protein signals likely arising from non-neuronal cells, an essential consideration in heterogeneous tissues such as the brain. Finally, we leverage this approach to resolve proteomic differences between dopaminergic neuron subpopulations with differential vulnerability to Parkinsons disease and to uncover disease-specific disruptions in -synuclein-aggregate-bearing single dopaminergic neurons. Together, these data demonstrate the utility of scSP in neuroscience research for understanding fundamental biology and the molecular drivers of neurological conditions.
]]></description>
<dc:creator>Dutta, S.</dc:creator>
<dc:creator>Pang, M.</dc:creator>
<dc:creator>Coughlin, G. M.</dc:creator>
<dc:creator>Gudavalli, S.</dc:creator>
<dc:creator>Roukes, M. L.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2025-02-11</dc:date>
<dc:identifier>doi:10.1101/2025.02.10.637505</dc:identifier>
<dc:title><![CDATA[Molecularly-guided spatial proteomics captures single-cell identity and heterogeneity of the nervous system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-02-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.02.12.637969v1?rss=1">
<title>
<![CDATA[
Perception and neural representation of intermittent odor stimuli in mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.02.12.637969v1?rss=1</link>
<description><![CDATA[
Odor cues in nature are sparse and highly fluctuating due to turbulent transport. To investigate how animals perceive these intermittent cues, we developed a behavioral task in which head-restrained mice made binary decisions based on the total number of discrete odor pulses presented stochastically over several seconds. Mice readily learned this task, and their performance was well-described by widely used decision models. Logistic regression of binary choices against the timing of odor pulses within the respiratory cycle revealed that mice placed higher perceptual weight to stimuli arriving during inhalation than exhalation, a phase dependency that strongly correlated with the magnitude of responses in olfactory sensory neurons. The population response of anterior piriform cortex (APCx) neurons to odor pulses was also modulated by respiration phase, although individual neurons displayed varying levels of phase-dependence. Single APCx neurons responded stochastically and transiently to odor pulses, leading to a representation that carries signatures of sensory evidence, but not its accumulation. Our study reveals that mice can integrate intermittent odor signals across dozens of breaths, but respiratory modulation of sensory inputs imposes limits on information acquisition that cortical circuits cannot overcome to improve behavior.
]]></description>
<dc:creator>Boero, L. E.</dc:creator>
<dc:creator>Wu, H.</dc:creator>
<dc:creator>Zak, J. D.</dc:creator>
<dc:creator>Masset, P.</dc:creator>
<dc:creator>Pashakhanloo, F.</dc:creator>
<dc:creator>Jayakumar, S.</dc:creator>
<dc:creator>Tolooshams, B.</dc:creator>
<dc:creator>Ba, D.</dc:creator>
<dc:creator>Murthy, V. N.</dc:creator>
<dc:date>2025-02-13</dc:date>
<dc:identifier>doi:10.1101/2025.02.12.637969</dc:identifier>
<dc:title><![CDATA[Perception and neural representation of intermittent odor stimuli in mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-02-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.02.17.638687v1?rss=1">
<title>
<![CDATA[
Transcriptome analysis of the winter tick (Dermacentor albipictus) reveals sex-specific expression patterns 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.02.17.638687v1?rss=1</link>
<description><![CDATA[
The winter tick, Dermacentor albipictus, is a significant ectoparasite of ruminants across North America, posing health risks to wildlife and occasionally humans. Despite its ecological importance, limited genomic resources exist for this species. This study provides the first comprehensive transcriptome analysis of D. albipictus, focusing on early-stage embryos, sexed adults, dissected ovaries, and dissected male reproductive systems. Differential gene expression analyses revealed significant sex-biased expression patterns, and functional annotations identified candidate genes involved in sex determination. Notably, we identified the first documented case of sex-specific splicing of a doublesex-like gene in chelicerates, a mechanism previously thought to be absent in this group. This discovery suggests that ticks may share more insect-like features of sexual differentiation, with implications for understanding the evolution of sex determination pathways in arthropods These transcriptome data serve as a critical resource for understanding the biology of D. albipictus and will facilitate the development of novel genetic control strategies.
]]></description>
<dc:creator>Edwards, R. T. M.</dc:creator>
<dc:creator>Antoshechkin, I.</dc:creator>
<dc:creator>Hill, E.</dc:creator>
<dc:creator>Perry, M. W.</dc:creator>
<dc:creator>Olafson, P. U.</dc:creator>
<dc:creator>Saelao, P.</dc:creator>
<dc:creator>Lohmeyer, K. H.</dc:creator>
<dc:creator>Akbari, O. S.</dc:creator>
<dc:date>2025-02-21</dc:date>
<dc:identifier>doi:10.1101/2025.02.17.638687</dc:identifier>
<dc:title><![CDATA[Transcriptome analysis of the winter tick (Dermacentor albipictus) reveals sex-specific expression patterns]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-02-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.02.17.638733v1?rss=1">
<title>
<![CDATA[
The forkhead transcription factor FKH-7/FOXP acts in chemosensory neurons to regulate developmental decision-making 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.02.17.638733v1?rss=1</link>
<description><![CDATA[
Autism is a complex neurodevelopmental disorder with many associated genetic factors, including the forkhead transcription factor FOXP1. Although FOXP1s neuronal role is well-studied, the specific molecular consequences of different FOXP1 pathogenic variants in physiologically-relevant contexts are unknown. Here we ascribe the first function to Caenorhabditis elegans FKH-7/FOXP, which acts in two chemosensory neuron classes to promote the larval decision to enter the alternative, developmentally-arrested dauer life stage. We demonstrate that human FOXP1 can functionally substitute for C. elegans FKH-7 in these neurons and that engineering analogous FOXP1 hypomorphic missense mutations in the endogenous fkh-7 locus also impairs developmental decision-making. In a fkh-7/FOXP1 missense variant, single-cell transcriptomics identifies downregulated expression of autism-associated kcnl-2/KCNN2 calcium-activated potassium channel in a serotonergic sensory neuron. Our findings establish a novel framework linking two evolutionarily-conserved autism-associated genes for deeper characterization of variant-specific molecular pathology at single neuron resolution in the context of a developmental decision-making paradigm.
]]></description>
<dc:creator>Chai, C. M.</dc:creator>
<dc:creator>Taylor, S. R.</dc:creator>
<dc:creator>Tischbirek, C. H.</dc:creator>
<dc:creator>Wong, W.-R.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:creator>Miller, D. M.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2025-02-21</dc:date>
<dc:identifier>doi:10.1101/2025.02.17.638733</dc:identifier>
<dc:title><![CDATA[The forkhead transcription factor FKH-7/FOXP acts in chemosensory neurons to regulate developmental decision-making]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-02-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.02.20.638743v1?rss=1">
<title>
<![CDATA[
Combining MicroED and native mass spectrometry for structural discovery of enzyme-biosynthetic inhibitor complexes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.02.20.638743v1?rss=1</link>
<description><![CDATA[
With the goal of accelerating the discovery of small molecule-protein complexes, we leverage fast, low-dose, event based electron counting microcrystal electron diffraction (MicroED) data collection and native mass spectrometry. This approach resolves structures of the epoxide-based cysteine protease inhibitor, and natural product, E-64, and its biosynthetic analogs bound to the model cysteine protease, papain. The combined structural power of MicroED and the analytical capabilities of native mass spectrometry (ED-MS) allows assignment of papain structures bound to E-64-like ligands with data obtained from crystal slurries soaked with mixtures of known inhibitors, and crude biosynthetic reactions. ED-MS further discriminates the highest-affinity ligand soaked into microcrystals from a broad inhibitor cocktail, and identifies multiple similarly high-affinity ligands soaked into microcrystals simultaneously. This extends to libraries of printed ligands dispensed directly onto TEM grids and later soaked with papain microcrystal slurries. ED-MS identifies papain binding to its preferred natural products, by showing that two analogues of E-64 outcompete others in binding to papain crystals, and by detecting papain bound to E-64 and an analogue from crude biosynthetic reactions, without purification. This illustrates the utility of ED-MS for natural product ligand discovery and for structure-based screening of small molecule binders to macromolecular targets.
]]></description>
<dc:creator>Vlahakis, N. W.</dc:creator>
<dc:creator>Flowers, C. W.</dc:creator>
<dc:creator>Liu, M.</dc:creator>
<dc:creator>Agdanowski, M.</dc:creator>
<dc:creator>Johnson, S.</dc:creator>
<dc:creator>Summers, J. A.</dc:creator>
<dc:creator>Keyser, C.</dc:creator>
<dc:creator>Russell, P.</dc:creator>
<dc:creator>Rose, S.</dc:creator>
<dc:creator>Orlans, J.</dc:creator>
<dc:creator>Adhami, N.</dc:creator>
<dc:creator>Chen, Y.</dc:creator>
<dc:creator>Sawaya, M. R.</dc:creator>
<dc:creator>Basu, S.</dc:creator>
<dc:creator>De Sanctis, D.</dc:creator>
<dc:creator>Wakatsuki, S.</dc:creator>
<dc:creator>Nelson, H. M.</dc:creator>
<dc:creator>Loo, J.</dc:creator>
<dc:creator>Tang, Y.</dc:creator>
<dc:creator>Rodriguez, J. A.</dc:creator>
<dc:date>2025-02-26</dc:date>
<dc:identifier>doi:10.1101/2025.02.20.638743</dc:identifier>
<dc:title><![CDATA[Combining MicroED and native mass spectrometry for structural discovery of enzyme-biosynthetic inhibitor complexes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-02-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.02.26.640391v1?rss=1">
<title>
<![CDATA[
Diversity and single-cell activity of endolithic microbes in sediment-hosted carbonate nodules within and below the sulfate-methane transition zone 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.02.26.640391v1?rss=1</link>
<description><![CDATA[
Authigenic carbonate concretions ( nodules) precipitate in marine seep sediments as a result of anaerobic oxidation of methane (AOM). These rocks host active endolithic microbial communities and persist as important methane sinks. Still, how these communities and their activity differ from those in adjacent seep sediments, particularly as a function of proximity to the sulfate-methane transition zone (SMTZ), remains understudied. Here, we sampled sediments and nodules within and below the SMTZ (0-57 cm deep) at four active deep-sea seep areas in Santa Monica Basin, CA. Measurements of high nodule porosities (43-51%) coupled to strong similarities between sediment and nodule 16S rRNA-based community profiles, including below the SMTZ, suggest continued perfusion and exchange between buried nodules and surrounding sediment. Shared, depth-dependent transitions in methanotrophic taxa (ANME-1, ANME-2, ANME-3) and methanogenic taxa (Methanofastidiosales) below the SMTZ were also consistent with trends in porewater methane and sulfate concentrations, porewater DIC, and nodule {delta}13C values -- underscoring the impact of different geochemical conditions on community structure and suggestive of under-characterized physiological plasticity in ANME-1. Laboratory-based BONCAT incubations of nodules within the SMTZ over [~]14-weeks revealed active sulfide production and translationally active endolithic microorganisms. However, cells from parallel nodule incubations recovered below the SMTZ showed weak-to-negligible BONCAT-based activity despite similar cell abundances -- suggestive of low activity on shorter timescales or dormancy. Together, these data challenge the interpretation of passively recorded microbiological signatures in seep sediment-hosted carbonate nodules and expand our understanding of how these endolithic communities may be actively shaped by past and present conditions.

ImportanceThis study advances earlier investigations of microbial communities in buried seep carbonate nodules by integrating microbiological profiles of nodules and sediments, sediment geochemistry, single-cell activity measurements, and nodule mineral, geochemical, and physical characteristics within and below the sulfate-methane transition zone in deep-sea methane seeps. This approach allows us to view how nodule-hosted, endolithic microbial communities change relative to their surrounding sediments across multiple geochemical contexts and better understand how formation history and environmental conditions might affect community identity and metabolic function. Results indicate that the seep nodule and surrounding sediment communities are closely linked across diverse geochemical conditions. This connectivity between sediments and carbonate nodules is distinct from that observed in exhumed seep carbonates, with implications regarding how microbial community composition within these nodules are interpreted, suggesting that instead of a passive recorder of the communities at the time of formation, these nodules appear to retain diverse, metabolically viable communities.
]]></description>
<dc:creator>Parra, S. A.</dc:creator>
<dc:creator>Mayr, M.</dc:creator>
<dc:creator>Mullahoo, J.</dc:creator>
<dc:creator>Quinn, L. K.</dc:creator>
<dc:creator>Wipfler, R. L.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2025-02-26</dc:date>
<dc:identifier>doi:10.1101/2025.02.26.640391</dc:identifier>
<dc:title><![CDATA[Diversity and single-cell activity of endolithic microbes in sediment-hosted carbonate nodules within and below the sulfate-methane transition zone]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-02-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.02.24.639918v1?rss=1">
<title>
<![CDATA[
Machine-Guided Dual-Objective Protein Engineering for Deimmunization and Therapeutic Functions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.02.24.639918v1?rss=1</link>
<description><![CDATA[
Cell and gene therapies often rely on the expression of exogenous proteins derived from nonhuman organisms. An emerging consensus is to reduce the potential immunogenicity of such therapies by instead using human protein domains. However, as we engineer these human-derived proteins, we create nonhuman peptides at the linkers or junctions between domains and at mutated residues within them, which still pose a risk of immunogenicity that has largely been left unaddressed. Here, we present a modular workflow to simultaneously optimize the functions of proteins and minimize their immunogenic risk using existing machine learning models that predict protein function and nonhuman peptide immunogenicity from their sequences. We first applied this workflow to existing transcriptional activation and bio-orthogonal RNA binding domains. Then we generated a set of small molecule-controllable transcription factors with human-derived zinc finger DNA-binding domains for targeting orthogonal non-genomic DNA sequences. Finally, we established a workflow for creating deimmunized zinc finger arrays to target arbitrary genomic DNA sequences and used it to upregulate expression of two therapeutically relevant genes, UTRN and SCN1A. Our future-proof, modular workflow offers a proof of principle for making cell and gene therapies safer and more efficacious through dual-objective protein optimization using state-of-the-art algorithms.
]]></description>
<dc:creator>Wolfsberg, E.</dc:creator>
<dc:creator>Paul, J.-S.</dc:creator>
<dc:creator>Tycko, J.</dc:creator>
<dc:creator>Chen, B.</dc:creator>
<dc:creator>Bassik, M. C.</dc:creator>
<dc:creator>Bintu, L.</dc:creator>
<dc:creator>Alizadeh, A. A.</dc:creator>
<dc:creator>Gao, X. J.</dc:creator>
<dc:date>2025-02-28</dc:date>
<dc:identifier>doi:10.1101/2025.02.24.639918</dc:identifier>
<dc:title><![CDATA[Machine-Guided Dual-Objective Protein Engineering for Deimmunization and Therapeutic Functions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-02-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.03.13.643040v1?rss=1">
<title>
<![CDATA[
The Neural Basis of Habit Formation Measured in Goal-Directed Response Switching 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.03.13.643040v1?rss=1</link>
<description><![CDATA[
To override ongoing habitual responses requires switching well-learned actions with new goal-directed processing. However, the neural circuits responsible for these processes remain unclear. This study infers habit strength by introducing a novel task capturing the increased cost associated with switching a habitual response. We employed neuroimaging and brain stimulation to examine the dynamic interactions between human brain regions involved in habits and their interference with ongoing incompatible goal-directed behavior. Training S-R links in overtrained stimuli (compared to less trained ones, termed standard-trained stimuli) increased RT switch costs, explained by drift diffusion computations governing both the training and outcome devaluation phases. Training engaged sensorimotor areas and the posterior putamen, whereas standard trained behaviors, recruited the posterior caudate, insula, and prefrontal regions. A cortical network orchestrated habit expression (right S1 with the left anterior insula/prefrontal areas) while also implicating basal ganglia when overriding habits (left premotor with the putamen). Importantly, stimulation of the left premotor played a causal role in habit control, enhancing performance across both the training and devaluation phases. Our findings reveal an interaction between habitual and goal-directed brain regions, highlighting shared neural dynamics when overriding habitual behaviors.
]]></description>
<dc:creator>Michiels, M.</dc:creator>
<dc:creator>Man, V.</dc:creator>
<dc:creator>Luque, D.</dc:creator>
<dc:creator>Obeso, I.</dc:creator>
<dc:date>2025-03-13</dc:date>
<dc:identifier>doi:10.1101/2025.03.13.643040</dc:identifier>
<dc:title><![CDATA[The Neural Basis of Habit Formation Measured in Goal-Directed Response Switching]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-03-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.03.12.642894v1?rss=1">
<title>
<![CDATA[
A nutrient bottleneck limits antibiotic efficacy in structured bacterial populations 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.03.12.642894v1?rss=1</link>
<description><![CDATA[
Antibiotic resistance is a growing global health threat. Therefore, it is critically important to optimize how existing antibiotics act against bacterial infections. Although antibiotic activity is well studied at the single cell level, many infections are caused by spatially structured multicellular populations. In such populations, cellular consumption of scarce nutrients establishes strong spatial variations in their abundance. These nutrient variations have long been hypothesized to help bacterial populations tolerate antibiotics, since single-cell studies show that antibiotic tolerance depends on metabolic activity, and thus, local nutrient availability. Here, we directly test this hypothesis by visualizing cell death in Escherichia coli populations with defined structures upon exposure to nutrient (glucose) and antibiotic (fosfomycin). We find that nutrient availability acts as a bottleneck to antibiotic killing, causing death to propagate through the population as a traveling front--a phenomenon predicted over 20 years ago, but never verified until now. By integrating our measurements with biophysical theory and simulations, we establish quantitative principles that explain how collective nutrient consumption can limit the progression of this "death front," protecting a population from a nominally deadly antibiotic dose. While increasing nutrient supply can overcome this bottleneck, our work reveals that in some cases, excess nutrient can unexpectedly promote the regrowth of resistant cells. Altogether, this work provides a key step toward predicting and controlling antibiotic treatment of spatially structured bacterial populations, yielding fundamental biophysical insights into collective behavior and helping to guide strategies for more effective antibiotic stewardship.
]]></description>
<dc:creator>Hancock, A. M.</dc:creator>
<dc:creator>Dill-Macky, A. S.</dc:creator>
<dc:creator>Moore, J. A.</dc:creator>
<dc:creator>Day, C.</dc:creator>
<dc:creator>Donia, M. S.</dc:creator>
<dc:creator>Datta, S. S.</dc:creator>
<dc:date>2025-03-14</dc:date>
<dc:identifier>doi:10.1101/2025.03.12.642894</dc:identifier>
<dc:title><![CDATA[A nutrient bottleneck limits antibiotic efficacy in structured bacterial populations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-03-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.03.13.642903v1?rss=1">
<title>
<![CDATA[
Vacuum and sonication treatment enables efficient transient gene expression in various monocot and eudicot plant seedlings 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.03.13.642903v1?rss=1</link>
<description><![CDATA[
Transient gene expression in intact plants is essential for rapidly addressing biological questions, where the current toolkit can be improved for higher efficiencies and broader plant species range. Here, we introduce VAST (Vacuum and Sonication-Assisted Transient expression): a transient transformation method that substantially enhances gene expression efficiency, reproducibility, and versatility across diverse monocot and eudicot intact seedlings. By systematically optimizing plant growth conditions and incorporating vacuum infiltration and sonication pre-treatments prior to seedling co-culture with Agrobacterium tumefaciens, we significantly improved transient gene expression efficiency while minimizing tissue damage compared to existing methods in Arabidopsis thaliana. We further demonstrated the broad applicability of VAST by successfully transforming key model and crop species, including tomato, Brassica rapa, Medicago sativa, Setaria italica (foxtail millet), switchgrass, and wheat. We also demonstrated a case study using the VAST-mediated transient transformation, where a cross-species analyses of nitrate-responsive gene expression highlighted both the conserved and diverged biological responses between the two model crops, A. thaliana and S. italica. VASTs simplicity, versatility, and efficiency provide a powerful tool for functional genomics, synthetic biology, and biotechnology research, opening new avenues for the rapid exploration of gene function, regulation, and editing in diverse plant systems.
]]></description>
<dc:creator>Li, E.</dc:creator>
<dc:creator>Geng, Y.</dc:creator>
<dc:creator>Khristoforova, T. R.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Jones, J. W.</dc:creator>
<dc:creator>Demirer, G. S.</dc:creator>
<dc:date>2025-03-14</dc:date>
<dc:identifier>doi:10.1101/2025.03.13.642903</dc:identifier>
<dc:title><![CDATA[Vacuum and sonication treatment enables efficient transient gene expression in various monocot and eudicot plant seedlings]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-03-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.03.13.643146v1?rss=1">
<title>
<![CDATA[
Revealing a coherent cell state landscape across single cell datasets with CONCORD 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.03.13.643146v1?rss=1</link>
<description><![CDATA[
Revealing the underlying cell-state landscape from single-cell data requires overcoming the critical obstacles of batch integration, denoising, and dimensionality reduction. Here, we present CONCORD, a unified framework that simultaneously addresses these challenges within a single self-supervised model. At its core, CONCORD implements a unified probabilistic sampling strategy that corrects batch effects via dataset-aware sampling and enhances biological resolution through hard-negative sampling. Remarkably, using only a minimalist neural network with a single hidden layer and contrastive learning, CONCORD surpasses state-of-the-art performance without relying on deep architectures, auxiliary losses, or external supervision. It seamlessly integrates data across batches, technologies, and even species to generate high-resolution cell atlases. The resulting latent representations are denoised and biologically meaningful--capturing gene co-expression programs, revealing detailed lineage trajectories, and preserving both local geometric relationships and global topological structures. We demonstrate CONCORDs broad applicability across diverse datasets, establishing it as a general-purpose framework for learning unified, high-fidelity representations of cellular identity and dynamics.
]]></description>
<dc:creator>Zhu, Q.</dc:creator>
<dc:creator>Jiang, Z.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:creator>Gartner, Z. J.</dc:creator>
<dc:date>2025-03-15</dc:date>
<dc:identifier>doi:10.1101/2025.03.13.643146</dc:identifier>
<dc:title><![CDATA[Revealing a coherent cell state landscape across single cell datasets with CONCORD]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-03-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.03.21.644500v1?rss=1">
<title>
<![CDATA[
Nucleotide and metalloid-driven conformational changes in the arsenite efflux ATPase ArsA 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.03.21.644500v1?rss=1</link>
<description><![CDATA[
A common mechanism of arsenic detoxification in bacteria is arsenite (AsIII) efflux facilitated by the ArsAB pump that couples metalloid transport to ATP hydrolysis. The cytoplasmic ATPase component, ArsA, binds and hydrolyzes ATP and facilitates the transfer of AsIII to the integral membrane transporter, ArsB. The underlying molecular mechanism of AsIII efflux by ArsAB remains unclear. ArsA is a member of the Intradimeric Walker A (IWA) family of ATPases that undergo dramatic nucleotide-dependent conformational changes to facilitate their respective biological functions. Similar conformational transitions in ArsA have been postulated to drive AsIII binding and transport via ArsB but have not been demonstrated. Here, we report multiple structures of ArsA determined by single-particle cryogenic electron microscopy in an open MgADP-bound state, open MgATP-bound state, and a distinct closed MgATP-bound state liganded to AsIII. Using X-ray absorption spectroscopy, we confirmed that AsIII coordinates three conserved cysteines at the metalloid-binding site of the closed state in a three-coordinate fashion. Coupled with biochemical characterization, our cryo-EM structures reveal key conformational changes in the ArsA catalytic cycle consistent with other members of the IWA family and provide the structural basis for allosteric activation of nucleotide hydrolysis by AsIII. This work enhances our understanding of how the ArsA catalytic cycle regulates metalloid efflux by ArsB.
]]></description>
<dc:creator>Mahajan, S.</dc:creator>
<dc:creator>Pall, A. E.</dc:creator>
<dc:creator>Li, Y. E.</dc:creator>
<dc:creator>Stemmler, T. L.</dc:creator>
<dc:creator>Rees, D. C.</dc:creator>
<dc:creator>Clemons, W. M.</dc:creator>
<dc:date>2025-03-21</dc:date>
<dc:identifier>doi:10.1101/2025.03.21.644500</dc:identifier>
<dc:title><![CDATA[Nucleotide and metalloid-driven conformational changes in the arsenite efflux ATPase ArsA]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-03-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.03.24.645084v1?rss=1">
<title>
<![CDATA[
The representation and valuation of subgoals in the human brain during model-based hierarchical behavior 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.03.24.645084v1?rss=1</link>
<description><![CDATA[
The human capacity to plan and perform long, complex sequences of behavior to achieve distant goals depends in part on a hierarchical organization that divides behavior into structured segments. Such a mechanism requires the internal designation of certain states as subgoals to mark the successful implementation of a behavioral segment. How the brain represents subgoals over time and computes decision values as a function of subgoals is unknown. While most characterizations of hierarchical behavior lack knowledge of the environment, human decision-making also relies on planning with an internal model of the world. Consequently, it remains to be determined how the brain computes values of subgoals using model-based planning in order to drive hierarchical, model-based decisions. Using a sequential-subgoal decision-making task designed to evoke hierarchical, model-based behavior in combination with fMRI, we decoded a representation of the current subgoal in insula and ventromedial prefrontal cortex during decision-making that persisted over time-a critical, latent representation for computing values and orienting behavior in the correct sequence. Using a model-based, hierarchical reinforcement learning model, we also found key decision signals based on values from the model in several regions of frontal cortex. These findings thereby shed light on the neural correlates of subgoal representation and illustrate how value signals can be computed on the basis of these subgoals and knowledge of the environment structure.
]]></description>
<dc:creator>Grossman, C. D.</dc:creator>
<dc:creator>Man, V.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:date>2025-03-25</dc:date>
<dc:identifier>doi:10.1101/2025.03.24.645084</dc:identifier>
<dc:title><![CDATA[The representation and valuation of subgoals in the human brain during model-based hierarchical behavior]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-03-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.08.647774v1?rss=1">
<title>
<![CDATA[
Pulsatory response of the BcLOV4 photoreceptor through intramolecular feed-forward regulation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.08.647774v1?rss=1</link>
<description><![CDATA[
Proteins are information processors, but their computations are typically considered at steady state. Here we find that individual proteins can dynamically encode information about their environment and that such response dynamics have been conserved throughout evolution. The fungal protein BcLOV4 exhibits pulsatory light responses shaped by the magnitude of environmental light and temperature. Response adaptation resulted from competitive interactions between domains that sensed either light or temperature. Temperature-sensing was encoded in a modular domain and could be tuned by mutations within co-evolved loops. Photo-thermal response dynamics were conserved in homologues from fungi that diverged >300 million years ago, and the characteristic temperature of pulsatory responses had adapted to match the ecological niche of the hosts, ranging from Antarctica to thermal ponds. These findings uncover a class of dynamic proteins, determine molecular principles of time-varying protein activation, and suggest functional importance for light- and temperature-conditioned protein activity pulses.

One-Sentence SummaryIndividual proteins can dynamically encode information through interactions between their component domains, revealing principles for complex signal processing in natural and engineered proteins.
]]></description>
<dc:creator>Huang, Z.</dc:creator>
<dc:creator>Forson, M.</dc:creator>
<dc:creator>Benman, W.</dc:creator>
<dc:creator>Gardner, K. H.</dc:creator>
<dc:creator>Bugaj, L. J.</dc:creator>
<dc:date>2025-04-14</dc:date>
<dc:identifier>doi:10.1101/2025.04.08.647774</dc:identifier>
<dc:title><![CDATA[Pulsatory response of the BcLOV4 photoreceptor through intramolecular feed-forward regulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.16.647665v1?rss=1">
<title>
<![CDATA[
Engineered protein circuits for cancer therapy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.16.647665v1?rss=1</link>
<description><![CDATA[
Many targeted therapies indirectly suppress cancer cells by inhibiting oncogenic signaling pathways such as Ras1-4. This renders them susceptible to resistance and limits their long-term clinical efficacy4-10. Engineered protein circuits11-25 have been envisioned as an alternative to pharmacological inhibition that directly rewires oncogenic activity to cell death. However, it has remained unclear whether engineered protein circuits can potently and safely treat cancers. Here, we show that Ras-targeting circuits can accurately discriminate between cancer and non-cancer cells, circumvent intrinsic and acquired resistance mechanisms that limit pharmacological inhibitors, and suppress cancer in vivo. These circuits combine three modules: a protease-based sensor that responds to a broad spectrum of clinically relevant Ras mutations, an optional protease amplifier, and protease-triggered cell death effectors. These effectors can flexibly trigger either non-inflammatory apoptosis or immunogenic pyroptosis, which has been shown to extend therapeutic effects beyond transfected cells26,27. The resulting sense-kill circuits can be safely, efficiently, and transiently delivered to cells as mRNA in lipid nanoparticles (LNPs). The circuits exhibited potent efficacy against Ras-mutant human cancer cell lines with minimal off-target killing of wild-type Ras cells. In immunocompetent mice bearing aggressive, multifocal Ras-driven liver tumors, systemically-delivered mRNA-LNP circuits significantly reduced tumor burden. Further, therapeutic circuits provided more potent killing of Ras-mutant cancer cells than the Ras inhibitors Sotorasib and RMC-79777,28-30, and exhibited increased sensitivity to Sotorasib-resistant cells in vitro. These results establish a potent, specific, and programmable mechanism for treating cancer and other human diseases.
]]></description>
<dc:creator>Lu, A. C.</dc:creator>
<dc:creator>Moeller, L.</dc:creator>
<dc:creator>Moore, S.</dc:creator>
<dc:creator>Xia, S.</dc:creator>
<dc:creator>Ho, K.</dc:creator>
<dc:creator>Zhang, E.</dc:creator>
<dc:creator>Budde, M. W.</dc:creator>
<dc:creator>Larson, H.</dc:creator>
<dc:creator>Ahmed Diaz, A.</dc:creator>
<dc:creator>Gu, B.</dc:creator>
<dc:creator>Linton, J. M.</dc:creator>
<dc:creator>Klock, L.</dc:creator>
<dc:creator>Flynn, M. J.</dc:creator>
<dc:creator>Gao, X. J.</dc:creator>
<dc:creator>Siegwart, D. J.</dc:creator>
<dc:creator>Zhu, H.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:date>2025-04-16</dc:date>
<dc:identifier>doi:10.1101/2025.04.16.647665</dc:identifier>
<dc:title><![CDATA[Engineered protein circuits for cancer therapy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.12.648490v1?rss=1">
<title>
<![CDATA[
KDM5B expression is suppressed by MYC in a negative feedback loop to promote cell survival. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.12.648490v1?rss=1</link>
<description><![CDATA[
Both c-MYC and KDM5B are global regulators of gene transcription, cell identity, and master transcription factors in hematopoietic malignancies. In this study we link these two critical factors in a negative feedback loop that controls apoptosis and cell survival. We find the MYC specifically downregulates KDM5B, thereby inhibiting its transcriptional repressive functions. Loss of KDM5B abrogates the cell death response to MYC withdrawal in MYC-dependent cells, indicating KDM5B mediates cell death. We find that KDM5B regulates the MYC network, and specifically demethylates the MYC locus. In summary we have discovered a negative feedback loop between MYC and KDM5B. The MYC-dependent suppression of KDM5B leads to a global increase in H3K4me3 methylation, transcriptional activity, and increase cell survival and tumor progression.
]]></description>
<dc:creator>Chatterjee, T.</dc:creator>
<dc:creator>Beffert, E.</dc:creator>
<dc:creator>Dewson, G. S.</dc:creator>
<dc:creator>Sullivan, D. K.</dc:creator>
<dc:creator>Anchang, B.</dc:creator>
<dc:creator>Sears, R. C.</dc:creator>
<dc:creator>Liefwalker, D.</dc:creator>
<dc:date>2025-04-18</dc:date>
<dc:identifier>doi:10.1101/2025.04.12.648490</dc:identifier>
<dc:title><![CDATA[KDM5B expression is suppressed by MYC in a negative feedback loop to promote cell survival.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.21.649868v1?rss=1">
<title>
<![CDATA[
AAVs Targeting Human Carbonic Anhydrase IV Enhance Gene Delivery to the Brain 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.21.649868v1?rss=1</link>
<description><![CDATA[
Clinically approved gene therapies based on natural adeno-associated virus (AAV) serotypes have restricted applications, particularly in the brain, due to their poor targeting, high dose requirements, and resulting safety concerns. Directed evolution of enhanced AAV capsids in mice or non-human primates (NHPs) has resulted in markedly improved performance in those species, but inter-species differences present a serious challenge for translating these vectors into human therapies. Here, we engineer AAVs to target human carbonic anhydrase IV (CA-IV), a recently identified blood-brain barrier (BBB) transcytosis receptor. Among known transcytosis receptors, CA-IV is notable for its relatively specific expression in brain endothelial cells and the potency of AAVs that target it in mice. CA-IVs AAV binding site, and thus the mouse vectors enhanced brain potency, is not conserved across species, so we employed a two-phase engineering strategy to identify AAVs optimized for human CA-IV-dependent gene delivery to the brain. We first used in vitro receptor-based selection of a vast AAV library to exclude capsids that do not bind human CA-IV, followed by in vivo selection in "humanized" mice expressing human CA-IV in brain endothelial cells. Notably, we find that human CA-IV binding capsid variants that were poorly enriched in the pull-down selection outperform strong binders in vivo. The most promising vector, AAV-hCA4-IV77, engages human CA-IV to achieve 100-fold greater brain transduction than AAV9, with robust neuronal and astrocytic coverage throughout multiple brain regions. These results advance our understanding of receptor-targeted capsid design and support the therapeutic potential of human CA-IV-engaging AAVs.
]]></description>
<dc:creator>Lin, C.</dc:creator>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>Hoang, J. D.</dc:creator>
<dc:creator>Ristic, F.</dc:creator>
<dc:creator>Fan, Y.</dc:creator>
<dc:creator>Jang, S.</dc:creator>
<dc:creator>Chung, J. H. A.</dc:creator>
<dc:creator>Sullivan, E. E.</dc:creator>
<dc:creator>Gawda, T.</dc:creator>
<dc:creator>Kavvathas, B.</dc:creator>
<dc:creator>Tran, I.</dc:creator>
<dc:creator>Li, Y.</dc:creator>
<dc:creator>Steele, A. D.</dc:creator>
<dc:creator>Shay, T. F.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2025-04-22</dc:date>
<dc:identifier>doi:10.1101/2025.04.21.649868</dc:identifier>
<dc:title><![CDATA[AAVs Targeting Human Carbonic Anhydrase IV Enhance Gene Delivery to the Brain]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.16.649237v1?rss=1">
<title>
<![CDATA[
VARS-fUSI: Variable Sampling for Fast and Efficient Functional Ultrasound Imaging using Neural Operators 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.16.649237v1?rss=1</link>
<description><![CDATA[
Functional ultrasound imaging (fUSI) is a promising neuroimaging method that infers neural activity by detecting cerebral blood volume changes. It offers high sensitivity and spatial resolution relative to fMRI and is an epidural alternative to electrophysiology for medical and neuroscience applications, including brain-computer interfaces. However, current fUSI methods require hundreds of compounded images and ultrasound pulse emissions, leading to high computational costs, memory demands, and potential probe heating. We propose VARiable Sampling fUSI (VARS-fUSI), the first deep learning fUSI method to allow for different sampling durations and rates during training and inference by using neural operators. VARS-fUSI reconstructs high-quality fUSI images using 10 - 15% of the time or sampling rate needed per image while preserving decodable behavior-correlated signals. Additionally, VARS-fUSI offers efficient finetuning for generalization to new animals and humans. Demonstrated across mouse, monkey, and human data, VARS-fUSI achieves state-of-the-art performance, enhancing imaging efficiency by significantly reducing storage and processing needs.
]]></description>
<dc:creator>Tolooshams, B.</dc:creator>
<dc:creator>Lin, L.</dc:creator>
<dc:creator>Callier, T.</dc:creator>
<dc:creator>Wang, J.</dc:creator>
<dc:creator>Pal, S.</dc:creator>
<dc:creator>Chandrashekar, A.</dc:creator>
<dc:creator>Rabut, C.</dc:creator>
<dc:creator>Li, Z.</dc:creator>
<dc:creator>Blagden, C.</dc:creator>
<dc:creator>Norman, S. L.</dc:creator>
<dc:creator>Azizzadenesheli, K.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:creator>Anandkumar, A.</dc:creator>
<dc:date>2025-04-23</dc:date>
<dc:identifier>doi:10.1101/2025.04.16.649237</dc:identifier>
<dc:title><![CDATA[VARS-fUSI: Variable Sampling for Fast and Efficient Functional Ultrasound Imaging using Neural Operators]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.17.649355v1?rss=1">
<title>
<![CDATA[
Exploring non-invasive sexing of early chick embryos in intact eggs using Laser Speckle Contrast Imaging (LSCI) and Deep Neural Network (DNN) 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.17.649355v1?rss=1</link>
<description><![CDATA[
The ability to image blood flow in early-stage avian embryos has significant applications in developmental biology, drug and vaccine testing, as well as determining sex differentiation. In this project, we used our recently developed laser speckle contrast imaging (LSCI) system to non-invasively image extraembryonic blood vessels and used these images to attempt early sex identification of chick embryos. Specifically, we captured images of blood vessels from 1,251 living chicken embryos between day three and day four of incubation. We then applied deep neural network (DNN) models to evaluate whether it is possible to differentiate sex based on vascular patterns. Using ResNetBiT and YOLOv5 models, our results indicate that sex differentiation from extraembryonic blood vessel images was not achievable with sufficiently high accuracy or statistical significance for practical use. Specifically, ResNetBiT had a five-fold cross-validated average accuracy of 59%{+/-}5% (fold-wise p-value, p [&le;] 0.3) at day 3 and 61%{+/-}3% (fold-wise, p [&le;] 0.04) at day 4. YOLOv5 had a five-fold cross-validated average accuracy of 55%{+/-}3% (fold-wise, p [&le;] 0.3) at day 3 and 53%{+/-}3% (fold-wise, p [&le;] 0.5) at day 4. Our findings suggest that using vascular pattern imaging alone is inconclusive for reliable early sex identification in chicken embryos.
]]></description>
<dc:creator>Mahler, S.</dc:creator>
<dc:creator>Arora, A.</dc:creator>
<dc:creator>Readhead, C.</dc:creator>
<dc:creator>Yin, S.</dc:creator>
<dc:creator>Hari, S. N.</dc:creator>
<dc:creator>Wang, E.</dc:creator>
<dc:creator>Moxley, C. I.</dc:creator>
<dc:creator>Adeboye, A. A.</dc:creator>
<dc:creator>Dong, Z.</dc:creator>
<dc:creator>Zhou, H.</dc:creator>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>Bronner, M.</dc:creator>
<dc:creator>Yang, C.</dc:creator>
<dc:date>2025-04-23</dc:date>
<dc:identifier>doi:10.1101/2025.04.17.649355</dc:identifier>
<dc:title><![CDATA[Exploring non-invasive sexing of early chick embryos in intact eggs using Laser Speckle Contrast Imaging (LSCI) and Deep Neural Network (DNN)]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.21.649828v1?rss=1">
<title>
<![CDATA[
Whole-Proteome Screening and Multi-Modal Profiling of Antigen-Specific CD4+ T Cells at Single-Cell Resolution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.21.649828v1?rss=1</link>
<description><![CDATA[
Systematic whole-proteome screening and comprehensive profiling of antigen-specific CD4+ T cells are crucial for advancing our understanding of CD4+ T cell immunity, yet such efforts remain technically challenging. Here, we present a high-throughput platform that employs large-scale class II single-chain trimer libraries to detect antigen-specific CD4+ T cells, while simultaneously profiling their antigen specificity, TCR/{beta} sequences, MHC restriction, whole transcriptomes, and patient/timepoint origins at single-cell resolution. We benchmarked SCTs against conventional pMHCs and validated the SCT library-based approach in direct ex vivo identification of antigen-specific CD4+ T cells in healthy donors. We then applied the platform to screen the entire SARS-CoV-2 receptor-binding domain in a longitudinal patient cohort, identifying 2,188 antigen-specific CD4+ T cells and revealing key features that define antigen immunogenicity. Extending to cancer, we performed whole-proteome screening of HPV-16 E6/E7 for TCR repertoire profiling in a precancerous cohort, uncovering functional heterogeneity of HPV-specific TCRs. By integrating high-throughput antigen screening with high-dimensional, multi-modal cellular characterization, our approach offers an unprecedented window into CD4+ T cell immunity across diverse disease contexts and empowers the development of new therapies.
]]></description>
<dc:creator>Zhang, R.</dc:creator>
<dc:creator>Qi, J.</dc:creator>
<dc:creator>McKasson, M.</dc:creator>
<dc:creator>Choi, J.</dc:creator>
<dc:creator>Gutierrez, V.</dc:creator>
<dc:creator>Brennan, C.</dc:creator>
<dc:creator>Hong, S.</dc:creator>
<dc:creator>Chour, W.</dc:creator>
<dc:creator>Ng, R. H.</dc:creator>
<dc:creator>Xie, J.</dc:creator>
<dc:creator>Yuan, D.</dc:creator>
<dc:creator>Webster, A.</dc:creator>
<dc:creator>Sidhu, S. K.</dc:creator>
<dc:creator>Anderson, A.</dc:creator>
<dc:creator>Chen, D.</dc:creator>
<dc:creator>Edmark, R.</dc:creator>
<dc:creator>Murray, K. M.</dc:creator>
<dc:creator>Li, S.</dc:creator>
<dc:creator>McDonald, C.</dc:creator>
<dc:creator>Rowen, L.</dc:creator>
<dc:creator>Wang, S.</dc:creator>
<dc:creator>Rasheed, Y.</dc:creator>
<dc:creator>Su, Y.</dc:creator>
<dc:creator>Wagner, J. R.</dc:creator>
<dc:creator>Chen, J.</dc:creator>
<dc:creator>Narwaly, K.</dc:creator>
<dc:creator>Fu, J.</dc:creator>
<dc:creator>Duven, A.</dc:creator>
<dc:creator>Forman, S. J.</dc:creator>
<dc:creator>Song, M.</dc:creator>
<dc:creator>Priceman, S.</dc:creator>
<dc:creator>Brown, C. E.</dc:creator>
<dc:creator>Ribas, A.</dc:creator>
<dc:creator>Wong, D.</dc:creator>
<dc:creator>Paulson, K. G.</dc:creator>
<dc:creator>Drescher, C. W.</dc:creator>
<dc:creator>Puig-Saus, C.</dc:creator>
<dc:creator>Goldman, J. D.</dc:creator>
<dc:creator>Trimble, C. L.</dc:creator>
<dc:creator>Heath, J. R.</dc:creator>
<dc:date>2025-04-23</dc:date>
<dc:identifier>doi:10.1101/2025.04.21.649828</dc:identifier>
<dc:title><![CDATA[Whole-Proteome Screening and Multi-Modal Profiling of Antigen-Specific CD4+ T Cells at Single-Cell Resolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.22.649955v1?rss=1">
<title>
<![CDATA[
SynGAP forms biocondensates at sub-micromolar concentrations and recruits PSD95 and receptor oligomers, functioning as a key initiator of PSD formation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.22.649955v1?rss=1</link>
<description><![CDATA[
A key issue in neuronal circuit regulation is how synapse formation is initiated. Synapse formation could start when one or more synaptic scaffold proteins that can initiate synapse formation reach certain threshold concentrations in the dendritic shaft, which might lead to their oligomerization or even liquid-liquid phase separation (LLPS). By combining in vitro reconstitution of purified proteins with live-cell single-molecule and confocal imaging, we demonstrated that SynGAP alone forms assemblies of nanoscale clusters containing several to several tens of molecules at 10-nM order concentrations and micron-scale LLPS hydrogel-like condensates at submicromolar concentrations. The trimers of SynGAP's intrinsically disordered region (IDR) induced by its coiled-coil domain are responsible for SynGAP condensation. CaMKII-mediated phosphorylation moderately suppresses SynGAP condensation, and also increases condensate liquidity. While PSD95 fails to form assemblies under these conditions, it is recruited to SynGAP condensates by specifically binding to the PDZ-binding motif of SynGAP. SynGAP[PSD95] condensates selectively immobilize postsynaptic transmembrane proteins, Neuroligin1 and AMPAR-TARP2 complexes, in a manner dependent on their oligomerization state, indicating cooperative recruitment dynamics among SynGAP, PSD95, and transmembrane components, which might mimic initial PSD assembly. These findings suggest that SynGAP may act as a primary nucleator of postsynaptic density assembly, challenging the PSD95-centered models.
]]></description>
<dc:creator>Acharya, S.</dc:creator>
<dc:creator>Tsunoyama, T. A.</dc:creator>
<dc:creator>Hoffmann, C.</dc:creator>
<dc:creator>Aguilar, P. G.</dc:creator>
<dc:creator>Meshcheryakova, I.</dc:creator>
<dc:creator>Nakamura-Norimoto, A.</dc:creator>
<dc:creator>Mastro, T.</dc:creator>
<dc:creator>Walkup, W. G.</dc:creator>
<dc:creator>Fujiwara, T. K.</dc:creator>
<dc:creator>Kennedy, M. B.</dc:creator>
<dc:creator>Milovanovic, D.</dc:creator>
<dc:creator>Kusumi, A.</dc:creator>
<dc:date>2025-04-23</dc:date>
<dc:identifier>doi:10.1101/2025.04.22.649955</dc:identifier>
<dc:title><![CDATA[SynGAP forms biocondensates at sub-micromolar concentrations and recruits PSD95 and receptor oligomers, functioning as a key initiator of PSD formation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.21.649844v1?rss=1">
<title>
<![CDATA[
Systematic cell-type resolved transcriptomes of 8 tissues in 8 lab and wild-derived mouse strains captures global and local expression variation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.21.649844v1?rss=1</link>
<description><![CDATA[
Mapping the impact of genomic variation on gene expression facilitates an understanding of the molecular basis of complex phenotypic traits and disease predisposition. Mouse models provide a controlled and reproducible framework for capturing the breadth of genomic variation observed in different genotypes across a wide variety of tissues. As part of the IGVF consortiums effort to catalog the effects of genetic variation, we uniformly characterized the transcriptomes of eight tissues from each mouse founder strain used to derive the Collaborative Cross strains, comprising five classical laboratory inbred strains and three wild-derived inbred strains. We sequenced samples from four male and four female replicates per tissue using single-nucleus RNA-seq to generate an "8-cube" dataset of 5.2 million nuclei across 106 cell types and cell states. As expected, the overall extent of transcriptome variation correlates positively with genetic divergence across the strains with the greatest differential between PWK/PhJ and CAST/EiJ. At the individual tissue level, heart and brain are relatively more similar across strains compared with gonads, adrenal, skeletal muscle, kidney, and liver. Further analyses revealed substantial strain variation, often concentrated in a few cell types as well as cell-state signatures that especially reflect strain-associated immune and metabolic trait differences. The founder 8-cube dataset provides rich transcriptome variation signatures to help explain strain-specific phenotypic traits and disease states, as illustrated by examples in tissue-resident immune cells, muscle degeneration, kidney sex differences, and the hypothalamicpituitary-adrenal axis. This data further provides a systematic foundation for the analysis of these tissues in the founder strains as well as the Collaborative Cross.
]]></description>
<dc:creator>Rebboah, E.</dc:creator>
<dc:creator>Weber, R.</dc:creator>
<dc:creator>Abdollahzadeh, E.</dc:creator>
<dc:creator>Swarna, N. P.</dc:creator>
<dc:creator>Sullivan, D. K.</dc:creator>
<dc:creator>Trout, D.</dc:creator>
<dc:creator>Reese, F.</dc:creator>
<dc:creator>Liang, H. Y.</dc:creator>
<dc:creator>Filimban, G.</dc:creator>
<dc:creator>Mahdipour, P.</dc:creator>
<dc:creator>Duffield, M.</dc:creator>
<dc:creator>Mojaverzargar, R.</dc:creator>
<dc:creator>Taghizadeh, E.</dc:creator>
<dc:creator>Fattahi, N.</dc:creator>
<dc:creator>Mojgani, N.</dc:creator>
<dc:creator>Zhang, H.</dc:creator>
<dc:creator>Loving, R. K.</dc:creator>
<dc:creator>Carilli, M.</dc:creator>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Kawauchi, S.</dc:creator>
<dc:creator>Hallgrimsdottir, I. B.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>MacGregor, G.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Wold, B.</dc:creator>
<dc:creator>Mortazavi, A.</dc:creator>
<dc:date>2025-04-24</dc:date>
<dc:identifier>doi:10.1101/2025.04.21.649844</dc:identifier>
<dc:title><![CDATA[Systematic cell-type resolved transcriptomes of 8 tissues in 8 lab and wild-derived mouse strains captures global and local expression variation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.24.650466v1?rss=1">
<title>
<![CDATA[
Subcellular proteomics of Paramecium tetraurelia reveals mosaic localization of glycolysis and gluconeogenesis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.24.650466v1?rss=1</link>
<description><![CDATA[
Ciliates are unicellular heterotrophic eukaryotes, most of which consume other microbes as prey. They exhibit nuclear dimorphism which requires reconstruction of a transcriptionally active macronucleus from the germline micronucleus after sexual recombination. This complex genomic structure has prevented the development of highly tractable genetic models leaving much of ciliate cell biology unexplored. To complicate matters further, some ciliates tend to accumulate many gene duplicates either singly or via whole genome duplications. Thus, extensive insight into the cell biology of ciliates requires the use of high-throughput tools like subcellular proteomics.

Here, we use a subcellular proteomics workflow to classify over 9,000 proteins to 16 subcellular compartments in Paramecium tetraurelia. From these data, we identify a small but robust subcellular cluster containing canonical mitochondrial outer membrane proteins as well as some ER proteins, putatively at membrane contact sites. Within this cluster, we identified the important glycolytic enzyme phosphofructokinase, which contained a transmembrane domain. Further investigation revealed that several latter-acting glycolytic enzymes were localized to the mitochondrial cluster. The location of phosphoenol pyruvate carboxykinase and pyruvate carboxylase in the mitochondria but pyruvate kinase in the cytosol suggests that ciliates prefer gluconeogenesis over glycolysis. The localization of these enzymes was confirmed in a preliminary subcellular proteome of Tetrahymena thermophila. In sum, our findings suggest that mitochondrial localization of glycolytic/gluconeogenic enzymes is widespread across ciliates and that several may preferentially undergo gluconeogenesis over glycolysis using amino acids as a primary carbon source in both catabolic and anabolic metabolism.

HighlightsSubcellular proteomics of Paramecium tetraurelia revealed that glycolytic and gluconeogenic enzymes are mosaically distributed between the cytosol, mitochondrial matrix, and mitochondrial outer membrane.
A distinct mitochondrial outer membrane compartment was identified with 105 classified proteins, including core mitochondrial biogenesis proteins and a putative Tom70-like protein.
Phosphofructokinase, a key glycolytic enzyme, was found embedded in the mitochondrial outer membrane.
Localization of biochemical pathways suggest ciliates favor gluconeogenesis over glycolysis.
In total, over 9000 Paramecium proteins were identified using subcellular proteomics and classified into 16 different cellular compartments.
]]></description>
<dc:creator>Jirsova, D.</dc:creator>
<dc:creator>Licknack, T.</dc:creator>
<dc:creator>Poh, Y.-P.</dc:creator>
<dc:creator>Qiu, Y.</dc:creator>
<dc:creator>Quan, N.</dc:creator>
<dc:creator>Karr, T.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Lynch, M.</dc:creator>
<dc:creator>Wideman, J. G.</dc:creator>
<dc:date>2025-04-25</dc:date>
<dc:identifier>doi:10.1101/2025.04.24.650466</dc:identifier>
<dc:title><![CDATA[Subcellular proteomics of Paramecium tetraurelia reveals mosaic localization of glycolysis and gluconeogenesis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.28.651135v1?rss=1">
<title>
<![CDATA[
LOSS OF ROR2 TYROSINE KINASE RECEPTOR IS ASSOCIATED WITH ENDOTHELIAL DYSFUNCTION IN PAH VIA INAPPROPRIATE INTEGRIN BETA 1 ACTIVATION 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.28.651135v1?rss=1</link>
<description><![CDATA[
RationaleEndothelial dysfunction is a key feature of pulmonary arterial hypertension (PAH). We previously identified Wnt7a, a ligand of the Wnt planar cell polarity (PCP) pathway, as essential for pulmonary angiogenesis, with its loss linked to PAH. Given the importance of Wnt/PCP to lung endothelial function and angiogenesis, our goal is to elucidate how Wnt/PCP regulates angiogenic responses in pulmonary microvascular endothelial cells (PMVECs). ROR2, a tyrosine kinase receptor specific to Wnt/PCP, is crucial for cardiovascular development, but its role in PAH is unclear. We hypothesized that ROR2 supports endothelial homeostasis, and its loss would impair angiogenesis, contributing to PAH.

MethodsEndothelial-specific ROR2 knockout (ROR2 ECKO) and wild-type (WT) mice were studied under normoxia and chronic hypoxia using echocardiography, hemodynamics, and lung morphometry. PMVECs from healthy and PAH lungs were transfected with ROR2 siRNA/constructs for functional and molecular studies. Focal adhesion (FA) activation and force generation were assessed via FRET-based methods. Bulk and single-cell transcriptomic analyses were performed on siROR2 PMVECs and ROR2 ECKO lungs.

ResultsROR2 ECKO mice exhibited worsened pulmonary hypertension, right ventricular remodeling, microvascular loss, and muscularization in hypoxia. Single-cell RNA sequencing of lung endothelial cells showed dysregulation of pathways involved in barrier formation and angiogenesis. Evans blue dye extravasation confirmed reduced endothelial barrier integrity in ROR2 ECKO mice. ROR2-deficient PAH PMVECs displayed increased adhesion, permeability, and FA numbers, with reduced VE-cadherin at cell junctions. Confocal imaging revealed ROR2 localization in FAs, interacting with integrin {beta}1 (ITGB1). FRET analysis showed that ITGB1 remained in an active, adhesion-promoting state in ROR2-deficient cells. Restoring ROR2 in PAH PMVECs normalized adhesion, barrier function, and FA abundance. Transcriptomic analysis identified Rab12 as a key mediator of ROR2-ITGB1 crosstalk, with Rab12 knockdown mimicking ROR2 deficiency in PMVECs.

ConclusionsROR2 regulates pulmonary angiogenesis by maintaining endothelial barrier integrity and facilitating integrin recycling. Restoring ROR2 signaling could be a potential therapeutic approach for PAH.
]]></description>
<dc:creator>Mitra, A.</dc:creator>
<dc:creator>Chakraborty, A.</dc:creator>
<dc:creator>Zhong, B.</dc:creator>
<dc:creator>Heo, L.</dc:creator>
<dc:creator>Agarwal, S.</dc:creator>
<dc:creator>Pacheco, A.</dc:creator>
<dc:creator>Auer, N.</dc:creator>
<dc:creator>Dunn, A.</dc:creator>
<dc:creator>Chelladurai, P.</dc:creator>
<dc:creator>Jain, A.</dc:creator>
<dc:creator>Matos, J.</dc:creator>
<dc:creator>Bankar, A.</dc:creator>
<dc:creator>Guardado, E.</dc:creator>
<dc:creator>YI, D.</dc:creator>
<dc:creator>Zhao, H.</dc:creator>
<dc:creator>Wai Dede Man, K.</dc:creator>
<dc:creator>Nair, R. V.</dc:creator>
<dc:creator>Guenat, O. T.</dc:creator>
<dc:creator>Dai, Z.</dc:creator>
<dc:creator>de Jesus Perez, V. A.</dc:creator>
<dc:date>2025-04-29</dc:date>
<dc:identifier>doi:10.1101/2025.04.28.651135</dc:identifier>
<dc:title><![CDATA[LOSS OF ROR2 TYROSINE KINASE RECEPTOR IS ASSOCIATED WITH ENDOTHELIAL DYSFUNCTION IN PAH VIA INAPPROPRIATE INTEGRIN BETA 1 ACTIVATION]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.04.28.650827v1?rss=1">
<title>
<![CDATA[
Is the whole the sum of its parts? Neural computation of consumer bundle valuation in humans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.04.28.650827v1?rss=1</link>
<description><![CDATA[
Humans are often tasked with making decisions about bundles of multiple items and very little is known about how the human brain aggregates, computes and represents value in such cases. We investigated how the human brain evaluates consumer items, both individually and in bundles, and how this activity relates to choice behavior. Participants underwent a deep-fMRI scanning protocol while we elicited behavioral valuations for single and bundled items. Behaviorally, we find that bundle values are sub-additively discounted compared to the sum of individual item values. Neurally, we find that the same distributed network in pre-frontal cortex computes the value of a bundle and its constituent individual items, but the value representation undergoes a normalization that actively re-scales across bundle and single item contexts. These findings suggest that generalized value regions contextually adapt within a valuation hierarchy, as opposed to utilizing an absolute value code.
]]></description>
<dc:creator>Cross, L. M.</dc:creator>
<dc:creator>Webb, R.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:date>2025-05-01</dc:date>
<dc:identifier>doi:10.1101/2025.04.28.650827</dc:identifier>
<dc:title><![CDATA[Is the whole the sum of its parts? Neural computation of consumer bundle valuation in humans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-05-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.05.02.651912v1?rss=1">
<title>
<![CDATA[
A SUMO-interacting motif in the guanine nucleotide exchange factor EPAC1 is required for subcellular targeting and function 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.05.02.651912v1?rss=1</link>
<description><![CDATA[
Exchange protein directly activated by cAMP (EPAC1), a multifunctional intracellular cAMP receptor, dynamically localizes to various cellular loci, engaging with diverse molecular partners to maintain cellular homeostasis. The study investigates the role of the SUMO interacting motif (SIM) in the subcellular targeting and cellular functions of EPAC1. It reveals that the SIM is a critical structural element for EPAC1s association with RanBP2/Nup358, a nucleoporin of the cytoplasmic filament component of the nuclear pore complex (NPC). Mutational disruption of EPAC1 SIM interferes with EPAC1s ability to activate its canonical effectors, small GTPases, Rap1 and Rap2, and non-canonical functions, such as the formation of nuclear condensates and cellular SUMOylation. Because SIM is also directly involved in cAMP binding, RanBP2s association with EPAC1 with the SIM attenuates EPAC1s cAMP binding affinity to generate an EPAC1 signaling microdomain with reduced cAMP sensitivity around the NPC. The coupling between EPAC1s scaffold association and cAMP binding enables EPAC1 to tune its sensitivity to stress stimuli spatially depending on the cellular locations. These findings provide novel structural insights into EPAC1 signaling, highlighting the importance of SIM in EPAC1s cellular functions and potential novel strategies for therapeutically targeting EPAC1.
]]></description>
<dc:creator>Yang, W.</dc:creator>
<dc:creator>Mei, F.</dc:creator>
<dc:creator>Lin, W.</dc:creator>
<dc:creator>Lee, J. E.</dc:creator>
<dc:creator>Nie, S.</dc:creator>
<dc:creator>Bley, C. J.</dc:creator>
<dc:creator>Hoelz, A. J.</dc:creator>
<dc:creator>Cheng, X.</dc:creator>
<dc:date>2025-05-03</dc:date>
<dc:identifier>doi:10.1101/2025.05.02.651912</dc:identifier>
<dc:title><![CDATA[A SUMO-interacting motif in the guanine nucleotide exchange factor EPAC1 is required for subcellular targeting and function]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-05-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.05.01.651783v1?rss=1">
<title>
<![CDATA[
Endothelial AGO1 Drives Vascular Inflammation and Atherosclerosis via a Non-Canonical Nuclear Mechanism 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.05.01.651783v1?rss=1</link>
<description><![CDATA[
BACKGROUNDEndothelial cell (EC) dysfunction is both a cause and consequence of vascular inflammation and lipid dysregulation in atherosclerosis, yet the molecular drivers linking EC dysfunction to systemic metabolic derangements remain incompletely understood. We previously identified Argonaute 1 (AGO1)--a canonical component of the RNA-induced silencing complex--as a regulator of EC function in angiogenesis and metabolism. In this study, we uncover a previously unrecognized, non-canonical role of nuclear AGO1 in ECs as a transcriptional coactivator of NF-{kappa}B, and demonstrate that EC-specific AGO1 inhibition simultaneously improves lipid metabolism, liver function, and vascular inflammation, thereby attenuating atherosclerosis.

METHODSEC-conditional AGO1 knockout (EC-AGO1-KO) and wildtype mice were subjected to pro-atherosclerotic models induced by AAV9-PCSK9 and a western diet, or carotid artery ligation. Metabolic and vascular phenotyping and gene expression analyses were performed. In human liver sinusoidal ECs (HLSECs) and human aortic ECs (HAECs), AGO1 was knocked down using antisense oligos (ASO), followed by assays for inflammatory responses (qPCR, RNA-seq, ELISA, and monocyte adhesion). Mechanistic studies included Cut&Tag sequencing, and chromatin immunoprecipitation assays, and EC-hepatocyte co-cultures. Therapeutic effect of AGO1 inhibition was assessed using lipid nanoparticle (LNP)-delivered ASO in mice.

RESULTSEC-AGO1-KO mice exhibited significantly improved plasma lipid profiles, reduced hepatic steatosis, inflammation, and fibrosis, and decreased aortic atherosclerotic burden. AGO1 knockdown in ECs dampened inflammatory responses and monocyte recruitment and enhanced hepatocyte lipid metabolism via paracrine signaling. Mechanistically, nuclear AGO1 interacted with NF-{kappa}B p65 to enhance transcription of pro-inflammatory genes including ICAM1, THBS1. LNP-delivered AGO1-ASO improved hyperlipidemia, liver function, and atherosclerosis without evident hepatotoxicity.

CONCLUSIONSEndothelial AGO1 promotes vascular inflammation and liver dysfunction through a non-canonical role as an NF-{kappa}B coactivator. Its inhibition provides dual benefits--ameliorating lipid dysregulation and suppressing vascular inflammation--highlighting EC-AGO1 as a promising therapeutic target for atherosclerosis and cardiometabolic diseases.
]]></description>
<dc:creator>Liu, X.</dc:creator>
<dc:creator>Yuan, D.</dc:creator>
<dc:creator>Luo, Y.</dc:creator>
<dc:creator>Tang, X.</dc:creator>
<dc:creator>Tapia, A.</dc:creator>
<dc:creator>Malhi, N. K.</dc:creator>
<dc:creator>Chadha, R. S.</dc:creator>
<dc:creator>Tiwari, S.</dc:creator>
<dc:creator>Swiderski, P.</dc:creator>
<dc:creator>Wang, K.-C.</dc:creator>
<dc:creator>Kortylewski, M.</dc:creator>
<dc:creator>Pardi, N.</dc:creator>
<dc:creator>Wei, L.</dc:creator>
<dc:creator>Huang, W.</dc:creator>
<dc:creator>Chen, Z. B.</dc:creator>
<dc:date>2025-05-07</dc:date>
<dc:identifier>doi:10.1101/2025.05.01.651783</dc:identifier>
<dc:title><![CDATA[Endothelial AGO1 Drives Vascular Inflammation and Atherosclerosis via a Non-Canonical Nuclear Mechanism]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-05-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.05.05.652215v1?rss=1">
<title>
<![CDATA[
CellTune: An integrative software for accurate cell classification in spatial proteomics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.05.05.652215v1?rss=1</link>
<description><![CDATA[
Spatial proteomics measures multiple proteins in situ, capturing tissue complexity. However, cell classification in densely packed tissues remains challenging due to the lack of efficient classification algorithms, annotation tools, and high-quality labeled datasets to benchmark computational methods. We introduce CellTune, an integrated software for analysis of large spatial proteomics datasets, which streamlines precise cell classification through an optimized human-in-the-loop active learning workflow. It advances core capabilities across within a unified, intuitive, and code-free interface. To evaluate CellTune, we created CellTuneDepot, a resource of 40k manually-annotated cells and 3.5 million high-quality labeled cells across 60 cell types. CellTune outperforms alternative methods, achieving accuracy comparable to human performance while enabling increased classification resolution and discovery of novel cell types. Together, CellTune and CellTuneDepot provide researchers with a tool for state-of-the-art classification accuracy and resolution at scale to drive biological insights.
]]></description>
<dc:creator>Bussi, Y.</dc:creator>
<dc:creator>Shainshein, D.</dc:creator>
<dc:creator>Ovits, E.</dc:creator>
<dc:creator>Posner, S.</dc:creator>
<dc:creator>Azulay, N.</dc:creator>
<dc:creator>Maimon, N.</dc:creator>
<dc:creator>Keidar Haran, T.</dc:creator>
<dc:creator>Ben-uri, R.</dc:creator>
<dc:creator>Brown, C.</dc:creator>
<dc:creator>Schuldiner, N.</dc:creator>
<dc:creator>Yaniv, E.</dc:creator>
<dc:creator>Van Valen, D. A.</dc:creator>
<dc:creator>Milo, I.</dc:creator>
<dc:creator>Elhanani, O.</dc:creator>
<dc:creator>Schiemann, R.</dc:creator>
<dc:creator>Keren, L.</dc:creator>
<dc:date>2025-05-09</dc:date>
<dc:identifier>doi:10.1101/2025.05.05.652215</dc:identifier>
<dc:title><![CDATA[CellTune: An integrative software for accurate cell classification in spatial proteomics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-05-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.05.07.652730v1?rss=1">
<title>
<![CDATA[
Spindle-localized F-actin regulates polar MTOC organization and the fidelity of meiotic spindle formation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.05.07.652730v1?rss=1</link>
<description><![CDATA[
Mammalian oocytes are notoriously prone to chromosome segregation errors leading to aneuploidy. The spindle provides the machinery for accurate chromosome segregation during cell division. Mammalian oocytes lack centrioles and, therefore, the meiotic spindle relies on the organization of numerous acentriolar microtubule organizing centers into two poles (polar MTOCs, pMTOCs). The traditional view is that, in mammalian oocytes, microtubules are the sole cytoskeletal component responsible for regulating pMTOC organization and spindle assembly. We identified a novel F-actin pool that surrounds pMTOCs, forming F-actin cage-like structure. We demonstrated that F-actin localization on the spindle depends on unconventional myosins X and VIIb. Selective disruption of spindle-localized F-actin, using myosin X/VIIb knockdown oocytes or photoswitchable Optojasp-1, perturbed pMTOC organization, leading to unfocused spindle poles and chromosome missegregation. Here, we unveil an important function of F-actin in regulating pMTOC organization, a critical process for ensuring the fidelity of meiotic spindle formation and proper chromosome segregation.
]]></description>
<dc:creator>Soto-Moreno, E. J.</dc:creator>
<dc:creator>Ali, N. N.</dc:creator>
<dc:creator>Kuller, F.</dc:creator>
<dc:creator>Nasufovic, V.</dc:creator>
<dc:creator>Frolikova, M.</dc:creator>
<dc:creator>Tepla, O.</dc:creator>
<dc:creator>Masata, J.</dc:creator>
<dc:creator>Trauner, D.</dc:creator>
<dc:creator>Patterson, A. A.</dc:creator>
<dc:creator>Arndt, H.-D.</dc:creator>
<dc:creator>Komrskova, K.</dc:creator>
<dc:creator>Zernicka-Goetz, M.</dc:creator>
<dc:creator>Glover, D. M.</dc:creator>
<dc:creator>Balboula, A. Z.</dc:creator>
<dc:date>2025-05-11</dc:date>
<dc:identifier>doi:10.1101/2025.05.07.652730</dc:identifier>
<dc:title><![CDATA[Spindle-localized F-actin regulates polar MTOC organization and the fidelity of meiotic spindle formation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-05-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.05.11.653354v1?rss=1">
<title>
<![CDATA[
Pseudoassembly of k-mers 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.05.11.653354v1?rss=1</link>
<description><![CDATA[
We introduce a pseudoassembly approach to identifying variation in sets of genomic sequences via colored de Bruijn graphs. Our pseudoassembly method is implemented in a program called klue that assembles k-mers into sequences compatible with a variant-aware extension of pseudoalignment. We show that this approach can be used to identify cell-type specific de novo variants from single-cell RNA-seq in a mouse melanoma model.
]]></description>
<dc:creator>Sullivan, D. K.</dc:creator>
<dc:creator>Boffelli, M.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2025-05-13</dc:date>
<dc:identifier>doi:10.1101/2025.05.11.653354</dc:identifier>
<dc:title><![CDATA[Pseudoassembly of k-mers]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-05-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.05.11.653328v1?rss=1">
<title>
<![CDATA[
Single-Cell Metabolic Imaging Reveals Glycogen Driven-Adaptations in Endothelial Cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.05.11.653328v1?rss=1</link>
<description><![CDATA[
Endothelial dysfunction (ED) is a defining feature of diabetes mellitus (DM) and a key contributor to many metabolic and cardiovascular diseases. Endothelial cells (ECs) are known to be highly glycolytic and primarily rely on glucose to meet their energy demands. However, the role of glycogen metabolism in ECs remains poorly characterized due to a lack of suitable tools. Here, we utilize stimulated Raman scattering (SRS) microscopy to investigate subcellular glycogen metabolism in live ECs under stress conditions associated with highly prevalent diabetes and diabetic complications. We demonstrate that ECs exposed to a diabetes-mimicking milieu- high glucose and tumor necrosis factor (TNF-)- divert excess glucose toward subcellular glycogen storage, and that this storage capacity is significantly enhanced by the inhibition of glycogen synthase kinase 3 (GSK3). Pulse-chase experiments uncover glycogen dynamics and reveal that glycogen is rapidly mobilized under glucose starvation, highlighting its role as an immediate energy reserve in ECs. We further extend the capabilities of SRS metabolic imaging to visualize glutamine and lactate metabolism for the first time, directly showcasing the reliance of ECs on these alternative carbon substrates during glucose deprivation. Our results indicate that ECs containing glycogen exhibit a reduced immediate metabolic demand for these gluconeogenic substrates in the absence of extracellular glucose. These findings suggest that glycogen may play a broader role beyond energy reserves in ECs by modulating stress-responsive metabolic adaptations and may offer potential therapeutic opportunities to address diabetes-induced ED and related cardiometabolic diseases.
]]></description>
<dc:creator>Chadha, R. S.</dc:creator>
<dc:creator>Yang, B.</dc:creator>
<dc:creator>Yuan, D.</dc:creator>
<dc:creator>Kocheril, P. A.</dc:creator>
<dc:creator>Mahajan, S.</dc:creator>
<dc:creator>Colazo, A.</dc:creator>
<dc:creator>Malhi, N. K.</dc:creator>
<dc:creator>Ambarian, J. A.</dc:creator>
<dc:creator>Liu, X.</dc:creator>
<dc:creator>Chen, Z. B.</dc:creator>
<dc:creator>Wei, L.</dc:creator>
<dc:date>2025-05-14</dc:date>
<dc:identifier>doi:10.1101/2025.05.11.653328</dc:identifier>
<dc:title><![CDATA[Single-Cell Metabolic Imaging Reveals Glycogen Driven-Adaptations in Endothelial Cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-05-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.05.11.653320v1?rss=1">
<title>
<![CDATA[
The Dynamics of Inducible Genetic Circuits 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.05.11.653320v1?rss=1</link>
<description><![CDATA[
Genes are connected in complex networks of interactions where often the product of one gene is a transcription factor that alters the expression of another. Many of these networks are based on a few fundamental motifs leading to switches and oscillators of various kinds. And yet, there is more to the story than which transcription factors control these various circuits. These transcription factors are often themselves under the control of effector molecules that bind them and alter their level of activity. Traditionally, much beautiful work has shown how to think about the stability of the different states achieved by these fundamental regulatory architectures by examining how parameters such as transcription rates, degradation rates and dissociation constants tune the circuit, giving rise to behavior such as bistability. However, such studies explore dynamics without asking how these quantities are altered in real time in living cells as opposed to at the fingertips of the synthetic biologists pipette or on the computational biologists computer screen. In this paper, we make a departure from the conventional dynamical systems view of these regulatory motifs by using statistical mechanical models to focus on endogenous signaling knobs such as effector concentrations rather than on the convenient but more experimentally remote knobs such as dissociation constants, transcription rates and degradation rates that are often considered. We also contrast the traditional use of Hill functions to describe transcription factor binding with more detailed thermodynamic models. This approach provides insights into how biological parameters are tuned to control the stability of regulatory motifs in living cells, sometimes revealing quite a different picture than is found by using Hill functions and tuning circuit parameters by hand.
]]></description>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Rousseau, R. J.</dc:creator>
<dc:creator>Mahdavi, S. D.</dc:creator>
<dc:creator>Garcia, H. G.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2025-05-15</dc:date>
<dc:identifier>doi:10.1101/2025.05.11.653320</dc:identifier>
<dc:title><![CDATA[The Dynamics of Inducible Genetic Circuits]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-05-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.05.12.653542v1?rss=1">
<title>
<![CDATA[
GFP-Free Live-Neuron Quantitative Imaging Reveals Compartmentalization and Growth Dynamics of PolyQ Aggregates 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.05.12.653542v1?rss=1</link>
<description><![CDATA[
Huntingtons Disease (HD), the most prevalent polyglutamine (polyQ) neurodegenerative disorder, features brain aggregates induced by mutant huntingtin (mHtt) proteins harboring expanded polyQ tracts. Despite extensive efforts, molecular mechanisms of polyQ aggregates remain elusive. Here we establish quantitative stimulated Raman scattering imaging of polyQ aggregates (q-aggSRS) for non-invasive investigations in live neuronal co-cultures using deuterated glutamine labeling. Q-aggSRS allows for specific visualization by targeting the distinct Raman peak from carbon-deuterium bonds, eliminating the need for bulky GFP tagging. Coupled with analysis from aggregate-tailored expansion microscopy, newly designed two-color imaging, and pulse-chase visualization, we comprehensively quantified the mHtt and non-mHtt proteins within the same aggregates across varying sizes, cell types, mHtt constructs, and subcellular locations. Our findings demonstrate a two-phase aggregate growth model with a distinct core-shell spatial organization, reveal significant heterogeneity in nucleus/cytoplasm compartmentalization specific to neurons, and identify previously unrecognized "gel-like" aggregates specifically in neuronal nuclei. These insights should advance our understanding of native polyQ aggregates and our proposed interaction coefficients may offer new quantitative parameters for developing effective HD therapies.
]]></description>
<dc:creator>Bi, X.</dc:creator>
<dc:creator>Lin, L.-E.</dc:creator>
<dc:creator>Miao, K.</dc:creator>
<dc:creator>Wei, L.</dc:creator>
<dc:date>2025-05-15</dc:date>
<dc:identifier>doi:10.1101/2025.05.12.653542</dc:identifier>
<dc:title><![CDATA[GFP-Free Live-Neuron Quantitative Imaging Reveals Compartmentalization and Growth Dynamics of PolyQ Aggregates]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-05-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.05.16.653860v1?rss=1">
<title>
<![CDATA[
Selective GSK3α Inhibition Promotes Self-Renewal Across Different Stem Cell States 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.05.16.653860v1?rss=1</link>
<description><![CDATA[
Pan-GSK3/{beta} inhibition promotes stem cell self-renewal through activation of WNT/{beta}-catenin signaling, but its broad effects complicate the precise control of stem cell states. Here, we show that selective inhibition of GSK3 with BRD0705 supports the long-term self-renewal of mouse embryonic stem cells (ESCs), epiblast stem cells (EpiSCs), and neural stem cells (NSCs), independent of {beta}-catenin signaling. When combined with the tankyrase inhibitor IWR1, BRD0705 broadly supports the maintenance of diverse pluripotent stem cell states, including ESCs, EpiSCs, and formative pluripotent stem cells. This BRD0705/IWR1 cocktail enables stable co-culture of naive ESCs and primed EpiSCs while preserving their distinct molecular and functional identities. Single-cell transcriptomics, epigenomic profiling, and functional assays confirm sustained lineage-specific features across stem cell types. These findings demonstrate that selective GSK3 inhibition enhances stemness by buffering against differentiation cues and promoting intrinsic self-renewal capacity. This work identifies GSK3 as a key regulator of self-renewal across distinct stem cell states and establishes a versatile culture system with broad applications.

In BriefWang et al. demonstrate that selective GSK3 inhibition with BRD0705 supports self-renewal of pluripotent and neural stem cells. Combined with IWR1, it enables long-term co-culture of naive and primed stem cells while preserving their distinct molecular and functional identities.

Graphical abstract

O_FIG O_LINKSMALLFIG WIDTH=181 HEIGHT=200 SRC="FIGDIR/small/653860v1_ufig1.gif" ALT="Figure 1">
View larger version (36K):
org.highwire.dtl.DTLVardef@4e371eorg.highwire.dtl.DTLVardef@104b287org.highwire.dtl.DTLVardef@164bd96org.highwire.dtl.DTLVardef@daf1ba_HPS_FORMAT_FIGEXP  M_FIG C_FIG HighlightsO_LIGSK3 inhibition by BRD0705 promotes self-renewal of ESCs, EpiSCs, and NSCs
C_LIO_LIBRD0705/IWR1 enables long-term co-culture of ESCs and EpiSCs
C_LIO_LICo-cultured ESCs and EpiSCs retain distinct naive or primed identities
C_LIO_LIBRD0705 preserves stem cell states independently of {beta}-catenin signaling
C_LI
]]></description>
<dc:creator>Wang, D.</dc:creator>
<dc:creator>Wang, X.</dc:creator>
<dc:creator>Wang, S.</dc:creator>
<dc:creator>Shi, K.-X.</dc:creator>
<dc:creator>Malki, S.</dc:creator>
<dc:creator>Chan, Y.</dc:creator>
<dc:creator>Feng, J.</dc:creator>
<dc:creator>Tang, J.</dc:creator>
<dc:creator>Chen, X.</dc:creator>
<dc:creator>McKim, D.</dc:creator>
<dc:creator>Zhang, C.</dc:creator>
<dc:creator>Hu, G.</dc:creator>
<dc:creator>Ying, Q.-L.</dc:creator>
<dc:date>2025-05-17</dc:date>
<dc:identifier>doi:10.1101/2025.05.16.653860</dc:identifier>
<dc:title><![CDATA[Selective GSK3α Inhibition Promotes Self-Renewal Across Different Stem Cell States]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-05-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.02.655683v1?rss=1">
<title>
<![CDATA[
Structural basis of liver de-targeting and neuronal tropism of CNS-targeted AAV capsids 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.02.655683v1?rss=1</link>
<description><![CDATA[
Crossing the blood-brain barrier while minimizing liver transduction is a key challenge in developing safe adeno-associated virus (AAV) vectors for treating brain disorders. In mice, the engineered capsid PHP.eB shows enhanced brain transduction, while the further engineered CAP-B10 is also de-targeted from astrocytes and liver. Here, we solve cryo-EM structures of CAP-B10 and its complex with AAV receptor (AAVR) domain PKD2, at 2.22 and 2.20 [A] resolutions, respectively. These structures reveal a structural motif that hinders AAVR binding, which we confirm by measuring affinities. We show that this motif is transferable to other capsids by solving cryo-EM structures of AAV9-X1 and AAV9-X1.1, without and with PKD2, at 3.09, 2.51, and 2.18 [A], respectively. Using this structural information, we designed and validated novel AAV variants with reduced liver and altered brain cell tropism in vivo. Overall, our findings demonstrate that rationally modulating AAVR affinity can alter liver targeting and cellular tropism.
]]></description>
<dc:creator>Brittain, T. J.</dc:creator>
<dc:creator>Jang, S.</dc:creator>
<dc:creator>Coughlin, G. M.</dc:creator>
<dc:creator>Barcelona, B. H.</dc:creator>
<dc:creator>Giriat, I.</dc:creator>
<dc:creator>Ristic, F.</dc:creator>
<dc:creator>Appling, N.</dc:creator>
<dc:creator>Chossis, C. P.</dc:creator>
<dc:creator>Shay, T. F.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2025-06-03</dc:date>
<dc:identifier>doi:10.1101/2025.06.02.655683</dc:identifier>
<dc:title><![CDATA[Structural basis of liver de-targeting and neuronal tropism of CNS-targeted AAV capsids]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.03.657675v1?rss=1">
<title>
<![CDATA[
Implantable CMOS Deep-Brain Fluorescence Imager with Single-Neuron Resolution 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.03.657675v1?rss=1</link>
<description><![CDATA[
Despite the advantages of optical imaging over electrophysiology, such as cell-type specificity, its application has been limited to the investigation of shallow brain regions (< 2 mm) because of the light scattering property of brain tissue. Passive optical conduits such as graded-index lenses and waveguides have permitted access to deeper locales but with restricted resolution and field of view, while creating massive lesions along the inserted path, with little pathway to improvement in the technology. As an alternative, we present the Acus device, an active implantable complementary metal-oxide-semiconductor (CMOS) neural imager with a 512-pixel silicon image sensor post- processed into a 4.1-mm-long, 120-m-wide shank with a collinear fiber for illumination, which is able to record transient fluorescent signals in deep brain regions at 400 frames/sec. Acus can achieve single-neuron resolution in functional imaging of GCaMP6s-expressing neurons at a frame rate of 400 frames/sec.
]]></description>
<dc:creator>Yilmaz, S.</dc:creator>
<dc:creator>Choi, J.</dc:creator>
<dc:creator>Uguz, I.</dc:creator>
<dc:creator>Kim, J.</dc:creator>
<dc:creator>Akrouh, A.</dc:creator>
<dc:creator>Taal, A. J.</dc:creator>
<dc:creator>Andino-Pavlovsky, V.</dc:creator>
<dc:creator>Yin, H.</dc:creator>
<dc:creator>Fabbri, J. D.</dc:creator>
<dc:creator>Moreaux, L.</dc:creator>
<dc:creator>Roukes, M. L.</dc:creator>
<dc:creator>Shepard, K. L.</dc:creator>
<dc:date>2025-06-06</dc:date>
<dc:identifier>doi:10.1101/2025.06.03.657675</dc:identifier>
<dc:title><![CDATA[Implantable CMOS Deep-Brain Fluorescence Imager with Single-Neuron Resolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.06.655161v1?rss=1">
<title>
<![CDATA[
Metabolic controls on the carbon isotope fractionations of bacterial fermentation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.06.655161v1?rss=1</link>
<description><![CDATA[
Microbial fermentation facilitates the initial breakdown of organic matter into small molecules, and is thought to be the rate-limiting step for mineralization under anoxic conditions. Fermentation is understudied in modern and ancient biogeochemistry due to a lack of environmental biomarkers that would constrain its activity. It has long been assumed that fermentation, like respiration, does not express significant carbon isotope fractionations, precluding isotopic signals as a means of studying it in nature. Here, we tested this idea by growing pure cultures of four fermenting bacteria on glucose and measuring the carbon isotope compositions of the organic acids and alcohols produced. We found that fermentation exhibits a strong carbon isotope fractionation, ranging from -6{per thousand} to +16{per thousand}, depending on the fermentation product. This range can even be observed within a single organism. Using bioisotopic models that track site-specific isotope enrichments through metabolic networks, we constrained the enzymes responsible for these fractionations. Our models reproduced in vivo organic acid{delta} 13C values in all four organisms. These findings demonstrate that acetate 13C-enrichment is likely a consistent signature of fermentation. Furthermore, our study suggests that fermentation imposes an anaerobic trophic carbon isotope fractionation as organic carbon is passed from fermenters to secondary degraders like sulfate reducers. Looking to the geologic past, this trophic fractionation could have imprinted isotopic signals on the three billion year record of sedimentary organic carbon, specifically the inverse{delta} 13C pattern of Precambrian acyclic isoprenoid and n-alkane biomarkers. Pervasive evidence of fermentation in the rock record suggests its under-appreciated role in biogeochemical cycles throughout Earth history.

Significance StatementMicroorganisms drive the global cycling of elements like carbon and regulate the Earths climate on both human and geologic timescales. Of particular importance is the microbial breakdown of organic matter, which generates greenhouse gases like methane. Fermenting bacteria play a crucial role in anaerobic carbon degradation. However, they remain largely invisible to our analyses. We explored the natural abundance of carbon stable isotopes in the molecular products of fermentation as a tool to study this metabolism in modern ecosystems and the ancient biosphere. We identified significant isotopic signals in molecules produced by fermenting bacteria and compared them to previously observed isotopic signals in molecular fossils in sedimentary rocks, which may provide evidence of microbial fermentation on the Precambrian Earth.
]]></description>
<dc:creator>Mueller, E.</dc:creator>
<dc:creator>Heuer, V. B.</dc:creator>
<dc:creator>Leadbetter, J. R.</dc:creator>
<dc:creator>Hinrichs, K.-U.</dc:creator>
<dc:creator>Sessions, A. L.</dc:creator>
<dc:date>2025-06-06</dc:date>
<dc:identifier>doi:10.1101/2025.06.06.655161</dc:identifier>
<dc:title><![CDATA[Metabolic controls on the carbon isotope fractionations of bacterial fermentation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.05.657862v1?rss=1">
<title>
<![CDATA[
Rational Design of Immunogenic Nanoparticles as a Platform for Enhanced Ovarian Cancer Immunotherapy in Mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.05.657862v1?rss=1</link>
<description><![CDATA[
Ovarian cancer immunotherapy remains a challenge based on the "cold" tumor microenvironment. Herein we present a rational design to create immunogenic nanoparticles as a multi-agent platform that promotes immune response in a mouse model of ovarian cancer. The hybrid lipid-silica nanosystem is capable of co-loading four types of cargo molecules including a model antigen, nucleic acid-based adjuvant Cytosine-p-linked to Guanine (CpG, TLR3/9 agonist), lipid-based adjuvant (MPLA, TLR4 agonist) integrated into the lipid coat, and optionally a small molecule drug, such as the chemotherapeutic agent oxaliplatin, a well-established treatment for ovarian cancer. The optimization of the nanoplatform in terms of lipid composition, functionalized silica dendritic core formation, and final charge, as well as their compatibility with the complex loading profile highlights an opportunity for enhanced survival of mice with advanced ovarian cancer compared to monotherapy. Furthermore, intraperitoneal administration led to preferential accumulation within tumor-burdened tissues with selective accumulation in myeloid cells. High myeloid cell cytotoxicity negated the benefits of oxaliplatin. The inclusion of CpG in the nanoparticle formulation enhanced the survival of mice with ovarian cancer. To interpret these outcomes and guide future design, we also developed a mathematical model of nanoparticle-driven immune activation, which quantified treatment efficacy and identified key parameters governing tumor response. The presented hybrid nanoparticle i tunable, enabling delivery of alternative molecules therefore, thereby highlighting a promising platform for the treatment of peritoneal cancers.

Graphical TOC

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=69 SRC="FIGDIR/small/657862v1_ufig1.gif" ALT="Figure 1000">
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]]></description>
<dc:creator>Tang, L.</dc:creator>
<dc:creator>Marwedel, B.</dc:creator>
<dc:creator>Dang, C.</dc:creator>
<dc:creator>Olewine, M.</dc:creator>
<dc:creator>Jun, M.</dc:creator>
<dc:creator>Naydenkov, P.</dc:creator>
<dc:creator>Medina, L. Y.</dc:creator>
<dc:creator>Gayoso, V.</dc:creator>
<dc:creator>Doan, N.</dc:creator>
<dc:creator>OLeary, S. L.</dc:creator>
<dc:creator>Schiavone, C.</dc:creator>
<dc:creator>Cave, J.</dc:creator>
<dc:creator>Howard, T.</dc:creator>
<dc:creator>Watt, J. D.</dc:creator>
<dc:creator>Dogra, P.</dc:creator>
<dc:creator>Serda, R. E.</dc:creator>
<dc:creator>Noureddine, A.</dc:creator>
<dc:date>2025-06-09</dc:date>
<dc:identifier>doi:10.1101/2025.06.05.657862</dc:identifier>
<dc:title><![CDATA[Rational Design of Immunogenic Nanoparticles as a Platform for Enhanced Ovarian Cancer Immunotherapy in Mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.06.657857v1?rss=1">
<title>
<![CDATA[
Biological Processes as Exploratory Dynamics 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.06.657857v1?rss=1</link>
<description><![CDATA[
Many biological processes can be thought of as the result of an underlying dynamics in which the system repeatedly undergoes distinct and abortive trajectories with the dynamical process only ending when some specific process, purpose, structure or function is achieved. A classic example is the way in which microtubules attach to kinetochores as a prerequisite for chromosome segregation and cell division. In this example, the dynamics is characterized by apparently futile time histories in which microtubules repeatedly grow and shrink without chromosomal attachment. We hypothesize that for biological processes for which it is not the initial conditions that matter, but rather the final state, this kind of exploratory dynamics is biologys unique and necessary solution to achieving these functions with high fidelity. This kind of cause and effect relationship can be contrasted to examples from physics and chemistry where the initial conditions determine the outcome. In this paper, we examine the similarities of many biological processes that depend upon random trajectories starting from the initial state and the selection of subsets of these trajectories to achieve some desired functional final state. We begin by reviewing the long history of the principles of dynamics, first in the context of physics, and then in the context of the study of life. These ideas are then stacked up against the broad categories of biological phenomenology that exhibit exploratory dynamics. We then build on earlier work by making a quantitative examination of a succession of increasingly sophisticated models for exploratory dynamics, all of which share the common feature of being a series of repeated trials that ultimately end in a "winning" trajectory. We also explore the ways in which microscopic parameters can be tuned to alter exploratory dynamics as well as the energetic burden of performing such processes.

OutlookIt is a great privilege to take part in this special volume dedicated to the life and work of Prof. Erich Sackmann (1934-2024). For one of us (RP), at the time of making a switch from traditional condensed matter physics to a life engaged in the study of life, he went to a meeting near Munich which completely opened his eyes to the ways in which the approach of physics could be brought to bear on the study of the living. Sackmanns work was an inspiring presence at that meeting. One of the hallmarks of his work was a principled approach to dissecting biological processes over a range of scales and phenomena. One common thread to much of his work was that it acknowledged the dynamical character of living organisms. The present paper attempts to follow in the tradition of Sackmanns studies of dynamics by suggesting a new way of looking at many biological processes all through the unifying perspective of what we will call exploratory dynamics.
]]></description>
<dc:creator>Kondev, J.</dc:creator>
<dc:creator>Kirschner, M. W.</dc:creator>
<dc:creator>Garcia, H. G.</dc:creator>
<dc:creator>Salmon, G.</dc:creator>
<dc:creator>Phillips, R.</dc:creator>
<dc:date>2025-06-09</dc:date>
<dc:identifier>doi:10.1101/2025.06.06.657857</dc:identifier>
<dc:title><![CDATA[Biological Processes as Exploratory Dynamics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.09.658710v1?rss=1">
<title>
<![CDATA[
A DNA part library for reliable engineering of the emerging model nematode symbiotic bacterium Xenorhabdus griffiniae HGB2511 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.09.658710v1?rss=1</link>
<description><![CDATA[
Xenorhabdus griffiniae is a bacterium that lives inside the intestine of the entomopathogenic nematode Steinernema hermaphroditum and partners with the nematode to infect and kill insect larvae in soil. The construction of gene circuits, like reporters, in X. griffiniae would provide tools to study and better understand the symbiotic relationship it has with its host. However, because X. griffiniae is not a model organism, information about gene circuit construction in X. griffiniae is limited. We develop and characterize a DNA part library similar to the CIDAR MoClo extension library for E. coli to allow more efficient construction of genetic circuits in X. griffiniae. TurboRFP expressing strains with different constitutive Anderson promoters and different ribosome binding sites (RBS) were constructed to quantify promoter and RBS strengths in X. griffiniae. Furthermore, two fluorescent proteins sfGFP and sfYFP, as well as the bioluminescent luxCDABE operon were added to the part library and successfully expressed in X. griffiniae. We then used the characterized parts to build and characterize IPTG inducible constructs.
]]></description>
<dc:creator>Larsson, E. M.</dc:creator>
<dc:creator>Wang, O. Y.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2025-06-09</dc:date>
<dc:identifier>doi:10.1101/2025.06.09.658710</dc:identifier>
<dc:title><![CDATA[A DNA part library for reliable engineering of the emerging model nematode symbiotic bacterium Xenorhabdus griffiniae HGB2511]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.09.658746v1?rss=1">
<title>
<![CDATA[
SpoIIE drives asymmetric cell division in B. subtilis by sequential modulation of the cytokinesis machinery 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.09.658746v1?rss=1</link>
<description><![CDATA[
To form a dormant spore, Bacillus subtilis and related endospore-forming bacteria divide asymmetrically to generate daughter cells of unequal size, the smaller of which becomes the spore. The transmembrane protein SpoIIE repositions the cell division machinery and controls cytokinesis during sporulation, but the molecular basis for the precise placement of the asymmetrical division site to the quarter cell point is unknown. Here, we applied live-cell fluorescence microscopy techniques to reveal that SpoIIE localizes with the treadmilling components of the cell division machinery. We found that SpoIIE opposes the inhibitory activity of the MinCD complex, which prevents assembly of Z-rings near the cell poles. Cells expressing a variant of SpoIIE with its transmembrane region replaced by an unrelated transmembrane anchor assembled condensed Z-rings that were unable to initiate constriction. This reveals a new function of SpoIIE and a possible checkpoint licensing cytokinesis downstream of Z-ring condensation. Potentially explaining the role of SpoIIE in cytokinesis, we demonstrated that SpoIIEs transmembrane region interacts with DivIB, an enigmatic structural component of the cell wall synthesis complex required for cytokinesis during sporulation. Finally, we found that FtsZ filaments are unusually short during sporulation, which requires the transmembrane domain of SpoIIE. Together, these results demonstrate that SpoIIE sequentially influences polar divisome assembly at distinct steps to drive asymmetric cell division.
]]></description>
<dc:creator>Ryan, A.</dc:creator>
<dc:creator>Squyres, G. R.</dc:creator>
<dc:creator>Holmes, M. J.</dc:creator>
<dc:creator>Bisson, A.</dc:creator>
<dc:creator>Garner, E. C.</dc:creator>
<dc:creator>Bradshaw, N.</dc:creator>
<dc:date>2025-06-10</dc:date>
<dc:identifier>doi:10.1101/2025.06.09.658746</dc:identifier>
<dc:title><![CDATA[SpoIIE drives asymmetric cell division in B. subtilis by sequential modulation of the cytokinesis machinery]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.09.658763v1?rss=1">
<title>
<![CDATA[
Thermally controlled state switches for macrophage immunotherapy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.09.658763v1?rss=1</link>
<description><![CDATA[
Advances in cellular immunotherapy promise new treatments for conditions such as cancer, autoimmune disease, and heart disease. While engineered cells have the ability to recognize clinically relevant signals, traffic to disease sites and interface with the host immune system, their activity must be tightly controlled to minimize undesirable effects in healthy tissues. One approach to obtaining specificity is to activate the cells spatially using externally applied energy, such as ultrasound-delivered heating. To facilitate such control, we designed and characterized a genetic circuit that enables stable transcriptional activation of macrophages after a brief thermal stimulus, resulting in the expression of reporters or secretion of the cytokine IL-12. We demonstrate that in vivo activation of a mouse macrophage cell line containing this bioswitch results in spatially localized gene expression for at least 14 days after ultrasound heating. This thermal bioswitch provides a precise control element for cell-therapeutic agents.
]]></description>
<dc:creator>Liu, A.</dc:creator>
<dc:creator>Farooq, A. S.</dc:creator>
<dc:creator>Abedi, M. H.</dc:creator>
<dc:creator>Smith, C. A. B.</dc:creator>
<dc:creator>Wu, D.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2025-06-13</dc:date>
<dc:identifier>doi:10.1101/2025.06.09.658763</dc:identifier>
<dc:title><![CDATA[Thermally controlled state switches for macrophage immunotherapy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.10.658913v1?rss=1">
<title>
<![CDATA[
Untangling overlapping barcodes in spatial genomics data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.10.658913v1?rss=1</link>
<description><![CDATA[
Difficulty in resolving spatially overlapping barcodes is a major bottleneck for imaging-based spatial genomics methods. Here, we present an approach for untangling overlapping barcodes by using strong encoding and global optimization to reduce spurious solutions resulting from recombinations of barcodes. We demonstrate experimentally that cellular regions with average local densities of 127 barcodes per {micro}m2 can be decoded with an estimated FDR of less than 4%, enabling a new type of super-resolution microscopy by coding.
]]></description>
<dc:creator>White, J. A.</dc:creator>
<dc:creator>Lu, C.</dc:creator>
<dc:creator>Ombelets, L.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:date>2025-06-16</dc:date>
<dc:identifier>doi:10.1101/2025.06.10.658913</dc:identifier>
<dc:title><![CDATA[Untangling overlapping barcodes in spatial genomics data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.16.660008v1?rss=1">
<title>
<![CDATA[
The nematode symbiotic bacterium Xenorhabdus griffiniae can sense and respond to the presence of its host Steinernema hermaphroditum 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.16.660008v1?rss=1</link>
<description><![CDATA[
The mutualistic symbiosis between Xenorhabdus bacteria and Steinernema nematodes has both ecological and practical importance. Their relationship co-evolved to make them dependent on each other in their life cycle where they kill, feed and reproduce within insect larvae together. This behavior has shed light on them as promising candidates to replace conventional pesticides. Despite the importance of the Xenorhabdus in insect-killing, the mechanisms by which the bacteria might sense and respond to the presence of their nematode host are not well understood. We performed an RNA-sequencing experiment on the bacterial partner, X. griffiniae, in close proximity, but not in direct contact with their host nematode, Steinernema hermaphroditum, to identify differentially regulated genes in these conditions, followed by genetic analysis to determine their functional significance. We show that X. griffiniae changes its transcriptomic profile in a small number of genes in the presence of axenic nematodes, but not in the presence of nematodes that are already colonized by X. griffiniae. We select the most differentially regulated gene, ymdA, for further investigation, and show that it plays a role in biofilm formation and affects host colonization efficiency. This work advances our understanding of bacterial sensing of nematodes and motivates future research in deepening our understanding of this underexplored ecological interaction.

ImportanceInteractions between different organisms in the soil environment are enabled by the ability to sense and respond to organisms nearby. In many cases, the underlying sensing mechanisms that mediate these ecologically important interactions are not known. Filling in the knowledge gap of how these interactions occur can help us understand how microbial populations organize themselves, establish symbiotic relationships, or compete with other species in complex environments. Furthermore, elucidating these mechanisms may inform the development of new tools in agriculture, such as improved biological control agents. Here we use the bacterial symbiont Xenorhabdus griffiniae of the entomopathogenic nematode Steinernema hermaphroditum to study whether symbiotic bacteria of nematodes are able to sense their presence. Our results suggest that X. griffiniae can sense the presence of its nematode host and respond by modulating the gene expression level of several genes, where at least one, ymdA, has implications for host colonization.
]]></description>
<dc:creator>Larsson, E. M.</dc:creator>
<dc:creator>Myers, C.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:creator>Cao, M.</dc:creator>
<dc:date>2025-06-16</dc:date>
<dc:identifier>doi:10.1101/2025.06.16.660008</dc:identifier>
<dc:title><![CDATA[The nematode symbiotic bacterium Xenorhabdus griffiniae can sense and respond to the presence of its host Steinernema hermaphroditum]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.11.659141v1?rss=1">
<title>
<![CDATA[
Sono-uncaging for Spatiotemporal Control of Chemical Reactivity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.11.659141v1?rss=1</link>
<description><![CDATA[
Photo-uncaging - the use of light to reveal the active part of a chemical compound by photolysis of a protecting group - has long been used to study and actuate biochemical processes. However, light scattering limits the applications of photo-uncaging in opaque specimens or tissues. Here, we introduce sono-uncaging, a process in which a chemical functional group becomes exposed upon the application of ultrasound, which can be applied and focused in optically opaque materials. We engineered gas vesicles (GVs), air-filled protein nanostructures sensitive to ultrasound, to contain cysteines on their concealed inner surface, hypothesizing that the application of ultrasound would collapse the GV shell and reveal the cysteines. The resulting SonoCage construct reacted with monobromobimane (mBBr), a fluorogenic, thiol-reactive molecule, only after treatment with ultrasound, establishing the sono-uncaging proof of concept. We then demonstrated the spatial patterning capability of sono-uncaging by embedding the SonoCages in an mBBr-containing hydrogel and creating fluorescent patterns with phased array ultrasound. This patterning could be accomplished using a diagnostic imaging transducer. This work establishes sono-uncaging as a method for spatiotemporal control over chemical reactivity using widely available ultrasound technology.
]]></description>
<dc:creator>Schrunk, E.</dc:creator>
<dc:creator>Lee, S.</dc:creator>
<dc:creator>Dutka, P.</dc:creator>
<dc:creator>Wu, D.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2025-06-17</dc:date>
<dc:identifier>doi:10.1101/2025.06.11.659141</dc:identifier>
<dc:title><![CDATA[Sono-uncaging for Spatiotemporal Control of Chemical Reactivity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.11.659185v1?rss=1">
<title>
<![CDATA[
Surface-Tethering Enhances Precision in Measuring Diffusion Within 3D Protein Condensates 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.11.659185v1?rss=1</link>
<description><![CDATA[
Biomolecular condensates, or membraneless organelles, play pivotal roles in cellular organization by compartmentalizing biochemical reactions and regulating diverse processes such as RNA metabolism, signal transduction, and stress response. Super-resolved imaging and single-molecule tracking are essential for probing the internal dynamics of these condensates, yet intrinsic Brownian (thermal capillary wave) motion of the entire condensate in vitro could introduce artifacts into diffusion measurements, confounding the interpretation of molecular mobility. Here, we systematically assess and address this question using both experiments and simulations. We deploy three surface-tethering strategies--using biotinylated DNA, protein, or antibody tethers--to immobilize FUS protein condensates on passivated glass surfaces. We show that tethering effectively suppresses the global translational and rotational Brownian motion of the entire condensate, eliminating inherent measurement artifacts while preserving their spherical appearance and native liquid-like properties. Quantitative analysis reveals that untethered condensates systematically overestimate or underestimate molecular diffusion coefficients and step sizes, particularly for slowly diffusing structured mRNAs, while rapidly diffusing unstructured RNAs are unaffected due to temporal scale separation. Comparative evaluation of tethering strategies demonstrates tunable control over condensate stability and internal dynamics, with implications for optimizing experimental design. Finally, simulations spanning the full physiological parameter space enable us to provide practical guidelines for assessing whether, and to what extent, tethering is beneficial, based on condensate size and the diffusion properties of the biomolecule of interest. Our findings establish surface tethering as a necessary and robust approach for accurate quantification of intra-condensate molecular dynamics, providing a methodological framework for future studies of membraneless organelles.

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]]></description>
<dc:creator>Sumrall, E. R.</dc:creator>
<dc:creator>Gao, G.</dc:creator>
<dc:creator>Stakenas, S.</dc:creator>
<dc:creator>Walter, N. G.</dc:creator>
<dc:date>2025-06-17</dc:date>
<dc:identifier>doi:10.1101/2025.06.11.659185</dc:identifier>
<dc:title><![CDATA[Surface-Tethering Enhances Precision in Measuring Diffusion Within 3D Protein Condensates]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.12.659428v1?rss=1">
<title>
<![CDATA[
Pulsed-laser lensing for phase modulation in electron microscopy 
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</title>
<link>https://biorxiv.org/content/10.1101/2025.06.12.659428v1?rss=1</link>
<description><![CDATA[
Phase contrast electron microscopy is fundamental for visualizing unstained biological specimens. Advances in electron detection have not yet overcome the low contrast caused by weak scattering. Here, we demonstrate that an orthogonal pulsed laser-electron beam interaction produces a pronounced peak phase shift of 430 radians through ponderomotive defocusing, leading to a maximum angular deflection of 45 {micro}rad. Experiments encompassing a variety of probe pulse energies and pump positions verified the properties of the electron pulses in a range of pulse durations from 5.8 {+/-} 1.9 ps to 13.4 {+/-} 0.9 ps and a width of 15.0 {+/-} 2.6 {micro}m at the interaction region. The stability of the beam was also tested across 10 hours of cumulative acquisition time, with only small variations in laboratory conditions resulting in a gradually shifting baseline measurement. Pulsed laser lensing of the electron beam offers the potential for refinement in phase shift and electron beam shaping with careful consideration to the overlap between laser and electron pulses. Calculations of phase shifts across a wide experimental envelope show that poorly chosen laser parameters can generate large incoherent distributions at both 30 keV and 300 keV. Thus, a delicate balance between laser and electron widths and pulse durations must be struck to adequately achieve uniform phase shifts, particularly when singling out specific beamlets in the back-focal-plane.
]]></description>
<dc:creator>Du, D. X.</dc:creator>
<dc:creator>Bartnik, A. C.</dc:creator>
<dc:creator>Duncan, C. J. R.</dc:creator>
<dc:creator>Choudhry, U.</dc:creator>
<dc:creator>Tabachnik, T.</dc:creator>
<dc:creator>Sallah, C.</dc:creator>
<dc:creator>Ogawa, Y.</dc:creator>
<dc:creator>Najafi, E.</dc:creator>
<dc:creator>Yang, D.-S.</dc:creator>
<dc:creator>Maxson, J. M.</dc:creator>
<dc:creator>Fitzpatrick, A. W. P.</dc:creator>
<dc:date>2025-06-17</dc:date>
<dc:identifier>doi:10.1101/2025.06.12.659428</dc:identifier>
<dc:title><![CDATA[Pulsed-laser lensing for phase modulation in electron microscopy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.13.659610v1?rss=1">
<title>
<![CDATA[
ER tethering and active transport govern condensate diffusion during hyperosmotic stress 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.13.659610v1?rss=1</link>
<description><![CDATA[
BackgroundHyperosmotic shock and the resulting cell volume compression are commonly experienced by organs such as the kidneys, causing rapid formation of hyperosmotic phase separation (HOPS) condensates in the cytoplasm and nucleoplasm. Although the tight relationship between hyperosmotic shock and condensation has been characterized, the dynamics of biomolecular condensates in hyperosmotically compressed cells and their regulatory mechanisms remain largely unknown.

ResultsWe used live-cell single-particle tracking (SPT) across different time scales to systematically characterize the dynamics of HOPS condensates formed by model protein mRNA decapping enzyme 1A (DCP1A). We found that HOPS condensates predominantly exhibited sub-diffusion rather than free diffusion, whereas some ([~]2%) exhibited short super-diffusion. Using tools measuring spatial accessibility inside cells and fluorescence labels for specific cellular organelles, we further revealed the origins of sub-diffusion and super-diffusion as endoplasmic reticulum (ER) attachment and coupling to microtubule-dependent active transport, respectively. Further, we reconstructed an accessibility map of the hyperosmotically compressed cell from trajectories of genetically encoded multimeric nanoparticles (GEMs), revealing that the cytoplasm of a compressed cell remains highly accessible without significant local corrals.

ConclusionsIn contrast to prior portrayals of the cytosolic space as static and constrained, our data suggest that the cytosol of a hyperosmotically compressed cell remains dynamic and accessible. Meanwhile, hyperosmotic and potentially other condensates can be spatially organized through docking to membrane structures, with intermittent episodes of long-range transport. These insights broaden our understanding of the physical environment within cells under hyperosmotic shock and provide a model for spatiotemporal organization of condensates via docking or coupling to existing cellular structures and processes.
]]></description>
<dc:creator>Halder, B.</dc:creator>
<dc:creator>Gao, G.</dc:creator>
<dc:creator>Ahnoud, A.</dc:creator>
<dc:creator>Stakenas, S.</dc:creator>
<dc:creator>Sumrall, E. R.</dc:creator>
<dc:creator>Walter, N. G.</dc:creator>
<dc:date>2025-06-17</dc:date>
<dc:identifier>doi:10.1101/2025.06.13.659610</dc:identifier>
<dc:title><![CDATA[ER tethering and active transport govern condensate diffusion during hyperosmotic stress]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.13.659624v1?rss=1">
<title>
<![CDATA[
Squidly: Enzyme Catalytic Residue Prediction Harnessing a Biology-Informed Contrastive Learning Framework 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.13.659624v1?rss=1</link>
<description><![CDATA[
Enzymes present a sustainable alternative to traditional chemical industries, drug synthesis, and bioremediation applications. Because catalytic residues are the key amino acids that drive enzyme function, their accurate prediction facilitates enzyme function prediction. Sequence similarity-based approaches such as BLAST are fast but require previously annotated homologs. Machine learning approaches aim to overcome this limitation; however, current gold-standard machine learning (ML)-based methods require high-quality 3D structures limiting their application to large datasets. To address these challenges, we developed Squidly, a sequence-only tool that leverages contrastive representation learning with a biology-informed, rationally designed pairing scheme to distinguish catalytic from non-catalytic residues using per-token Protein Language Model embeddings. Squidly surpasses state-of-the-art ML annotation methods in catalytic residue prediction while remaining sufficiently fast to enable wide-scale screening of databases. We ensemble Squidly with BLAST to provide an efficient tool that annotates catalytic residues with high precision and recall for both in- and out-of-distribution sequences.
]]></description>
<dc:creator>Rieger, W. J.</dc:creator>
<dc:creator>Boden, M.</dc:creator>
<dc:creator>Arnold, F. H.</dc:creator>
<dc:creator>Mora, A.</dc:creator>
<dc:date>2025-06-20</dc:date>
<dc:identifier>doi:10.1101/2025.06.13.659624</dc:identifier>
<dc:title><![CDATA[Squidly: Enzyme Catalytic Residue Prediction Harnessing a Biology-Informed Contrastive Learning Framework]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.17.660179v1?rss=1">
<title>
<![CDATA[
Tau-seed interactome analysis reveals distinct functional signatures in Alzheimer's disease across model systems. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.17.660179v1?rss=1</link>
<description><![CDATA[
Tau aggregates propagate through the brain in a prion-like manner in Alzheimers disease (AD) and other tauopathies, but the molecular identity and functional partners of the seeding-competent Tau species remain poorly defined. Here, we present an unbiased proteomic profiling of a high-molecular-weight (HMW) Tau-seed isolated from AD patient brains. We contrast this interactome with that of a biochemically similar, seeding-incompetent HMW-Tau species from age-matched healthy controls. Despite comprising less than 5% of total Tau in the brain, Tau-seed associates with a distinct set of proteins enriched in synaptic, mitochondrial, and vesicle-trafficking functions. Cross-species functional screening in Drosophila and mouse models identifies interactors that modulate Tau toxicity and seeding. Spatially resolved analysis of postmortem AD brains reveals heterogenous co-deposition of these proteins with Tau aggregates, suggesting functionally distinct Tau-seed complexes. Together, this dataset provides a framework for understanding selective Tau-seed toxicity and identifies candidate regulators of Tau propagation with therapeutic potential.
]]></description>
<dc:creator>Martinez, P.</dc:creator>
<dc:creator>Patel, H.</dc:creator>
<dc:creator>You, Y.</dc:creator>
<dc:creator>Lopes, D.</dc:creator>
<dc:creator>Amaro, A.</dc:creator>
<dc:creator>Jury-Garfe, N.</dc:creator>
<dc:creator>Min, Y.</dc:creator>
<dc:creator>Redding-Ochoa, J.</dc:creator>
<dc:creator>Dutta, S.</dc:creator>
<dc:creator>Rochet, C.</dc:creator>
<dc:creator>Ertekin-Taner, N.</dc:creator>
<dc:creator>Troncoso, J.</dc:creator>
<dc:creator>Lasagna-Reeves, C. A.</dc:creator>
<dc:date>2025-06-20</dc:date>
<dc:identifier>doi:10.1101/2025.06.17.660179</dc:identifier>
<dc:title><![CDATA[Tau-seed interactome analysis reveals distinct functional signatures in Alzheimer's disease across model systems.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.22.660940v1?rss=1">
<title>
<![CDATA[
Expansion of chromosome F heterochromatin in parthenogenetic Drosophila mercatorum 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.22.660940v1?rss=1</link>
<description><![CDATA[
The dramatic transition to parthenogenetic reproduction is often accompanied by similarly dramatic changes in genome organization. Genomic changes may precede or succeed the onset of parthenogenesis and may directly or indirectly contribute to the success of this reproductive transition and fitness of parthenogenetic animals. To gain greater understanding of genomic changes accompanying the transition to parthenogenetic reproduction, we have characterized genomic differences between a sexually reproducing and parthenogenetic strain of Drosophila mercatorum. This revealed three large (2.6-9 Mbp) inversions present on Muller element B and a 30-fold length expansion of heterochromatin on Muller element F. Comparisons of these genomic changes and parthenogenetic ability in 18 D. mercatorum strains collected in South America, North America, Hawaii, and Africa indicates no clear correlation of these genomic changes with geographical origin. However, these changes are minimal in strains collected in Brazil suggesting this is the origin for the ancestral strain and that both chromosome inversions and increased heterochromatin have likely preceded the transition to parthenogenetic reproduction. Parthenogenetic ability correlates most strongly with expansion of chromosomal element F. We speculate that this increased heterochromatic environment of genes on element F influences gene expression to either enhance parthenogenesis directly or redirect the activity of another factor contributing to it, in a manner analogous to the known influence of heterochromatin on gene activity in position effect variegation.
]]></description>
<dc:creator>Sperling, A. L.</dc:creator>
<dc:creator>Fabian, D. K.</dc:creator>
<dc:creator>Glover, D. M.</dc:creator>
<dc:date>2025-06-27</dc:date>
<dc:identifier>doi:10.1101/2025.06.22.660940</dc:identifier>
<dc:title><![CDATA[Expansion of chromosome F heterochromatin in parthenogenetic Drosophila mercatorum]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.24.661128v1?rss=1">
<title>
<![CDATA[
Functionalizing hydrogel nanovials with vesicles mimicking antigen-presenting vesicles and cancer exosomes improves T cell capture and activation 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.24.661128v1?rss=1</link>
<description><![CDATA[
Recent advances have demonstrated the application of microcavity-containing hydrogel microparticles, known as nanovials, for the massively parallel and high-throughput screening of therapeutic T cell populations for adoptive cell therapies. Nanovial cavities coated with peptide-MHC (pMHC) or antigen tetramers selectively bind to their cognate T cell receptor (TCR) or chimeric antigen receptor (CAR) to activate T cells and capture secreted cytokines. However, binding of tetramers or recombinantly expressed antigen by T cells is not always correlated with T cell activation or cytotoxicity as the binding interface is not fully representative of the natural immunological synapse formed between T cells and professional antigen-presenting cells (APCs). Here, we leverage the recent discovery of an ESCRT- and ALIX-binding region (EABR) sequence to generate antigen-presenting vesicles and cancer-mimicking exosomes from standard HEK293T and Expi293F cell cultures. EABR-mediated vesicles present natural, full-length oncologically-relevant membrane proteins embedded in lipid bilayers to functionalize the nanovial cavity with cell-like membranes. These hydrogel nanovials functionalized with the EABR-mediated vesicles show improved T cell capture of 1G4 T cells and enhanced activation of HER2 CAR-T cells compared to hydrogel surfaces functionalized with recombinantly-expressed soluble proteins.
]]></description>
<dc:creator>Olson, B. A.</dc:creator>
<dc:creator>Mellody, M. P.</dc:creator>
<dc:creator>Soemardy, C.</dc:creator>
<dc:creator>Mao, Z.</dc:creator>
<dc:creator>Mei, A.</dc:creator>
<dc:creator>Lippert, K.</dc:creator>
<dc:creator>Hoffmann, M. A. G.</dc:creator>
<dc:creator>Di Carlo, D.</dc:creator>
<dc:creator>Mayo, S. L.</dc:creator>
<dc:date>2025-06-27</dc:date>
<dc:identifier>doi:10.1101/2025.06.24.661128</dc:identifier>
<dc:title><![CDATA[Functionalizing hydrogel nanovials with vesicles mimicking antigen-presenting vesicles and cancer exosomes improves T cell capture and activation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.27.661967v1?rss=1">
<title>
<![CDATA[
Core microRNAs regulate neural crest delamination and condensation in the developing trigeminal ganglion 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.27.661967v1?rss=1</link>
<description><![CDATA[
Cranial neural crest cells (NCCs) undergo dynamic processes during embryonic development, including delamination from the neural tube by epithelial-to-mesenchymal transition (EMT), migration to the periphery, condensation via mesenchymal-to-epithelial transition (MET) and differentiation into structures like the trigeminal ganglion. Here, we identify and characterize the function of a core set of miRNAs involved in these transitions during the formation of the trigeminal ganglion in the chick embryo. We further identify putative targets of miRNAs involved in neural crest EMT and MET. Notably, introducing MET-involved miRNAs into trunk NCCs endows these cells with the ability to condense and differentiate into neurons in vivo in a manner reminiscent of cranial rather than trunk NCCs. Our findings shed light on the intricate regulatory networks governing NCC behavior, positioning miRNAs as key regulatory elements required for migratory transitions and axial level specific differentiation capabilities.
]]></description>
<dc:creator>Marquez, R. B.</dc:creator>
<dc:creator>Sanchez Vazquez, E.</dc:creator>
<dc:creator>Alonso, A. M.</dc:creator>
<dc:creator>Bernardi, Y. E.</dc:creator>
<dc:creator>Santillan, E. M.</dc:creator>
<dc:creator>Lwigale, P.</dc:creator>
<dc:creator>Cochella, L.</dc:creator>
<dc:creator>Bronner, M.</dc:creator>
<dc:creator>Strobl-Mazzulla, P. H.</dc:creator>
<dc:date>2025-06-28</dc:date>
<dc:identifier>doi:10.1101/2025.06.27.661967</dc:identifier>
<dc:title><![CDATA[Core microRNAs regulate neural crest delamination and condensation in the developing trigeminal ganglion]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.26.661577v1?rss=1">
<title>
<![CDATA[
Representation Learning Methods for Single-Cell Microscopy are Confounded by Background Cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.26.661577v1?rss=1</link>
<description><![CDATA[
Deep learning models are widely used to extract feature representations from microscopy images. While these models are used for single-cell analyses, such as studying single-cell heterogeneity, they typically operate on image crops centered on individual cells with background information present, such as other cells, and it remains unclear to what extent the conclusions of single-cell analyses may be altered by this. In this paper, we introduce a novel evaluation framework that directly tests the robustness of crop-based models to background information. We create synthetic single-cell crops where the center cells localization is fixed and the background is swapped--e.g., with backgrounds from other protein localizations. We measure how different backgrounds affect localization classification performance using model-extracted features. Applying this framework to three leading models for single-cell microscopy for analyzing yeast protein localization, we find that all lack robustness to background cells. Localization classification accuracy drops by up to 15.8% when background cells differ in localization from the center cell compared to when the localization is the same. We further show that this lack of robustness can affect downstream biological analyses, such as the task of estimating proportions of cells for proteins with single-cell heterogeneity in localization. Ultimately, our framework provides a concrete way to evaluate single-cell model robustness to background information and highlights the importance of learning background-invariant features for reliable single-cell analysis.1
]]></description>
<dc:creator>Gupta, A.</dc:creator>
<dc:creator>Moses, A.</dc:creator>
<dc:creator>Lu, A. X.</dc:creator>
<dc:date>2025-06-30</dc:date>
<dc:identifier>doi:10.1101/2025.06.26.661577</dc:identifier>
<dc:title><![CDATA[Representation Learning Methods for Single-Cell Microscopy are Confounded by Background Cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.30.662270v1?rss=1">
<title>
<![CDATA[
Deep sea anaerobic microbial community couples the degradation of insoluble chitin to extracellular electron transfer 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.30.662270v1?rss=1</link>
<description><![CDATA[
Chitin is a major structural component of arthropod exoskeletons, and an important carbon and nitrogen source in marine environments. In anoxic sediments, its degradation generates chitooligosaccharides and N-acetylglucosamine (GlcNAc), which are fermented into smaller organic molecules and oxidized anaerobically using soluble electron acceptors or insoluble ones such as metal oxides. To date, many aspects of chitin degradation in deep-sea anoxic sediments have been overlooked, including the potential coupling of insoluble chitin degradation to metal oxide reduction, the involvement of extracellular electron transfer (EET), and the spatial organization of the microorganisms involved. Using anoxic deep-sea sediments recovered from a whale fall site, we developed an innovative workflow based on electrochemical reactors, to characterize chitin degradation in these environments. Sediment samples enriched on poorly crystalline iron oxides, and subsequently transferred into an electrochemical reactor poised at +0.22 V vs SHE, showed active anodic current production when supplied with chitin, which increased 2-fold when amended with GlcNAc. Chitin reactors were dominated by Vallitalea (Firmicutes), Spirochaetota, Gammaproteobacteria and Desulfobacterota. Exoenzyme activity assays, metabolite profiling, and continued anodic current production confirmed ongoing chitin degradation linked to EET. We observed metabolic associations between chitin degraders and secondary consumers using in situ imaging (16S rRNA gene FISH coupled with BONCAT and nanoSIMS). These microbial partners, within the electrode-attached community, required close proximity to the poised electrode ([&le;] 10 {micro}m) to remain metabolically active. Supporting these observations, cultured isolates of Vallitalea sp. and Trichloromonas sp. recovered from the whale fall site exhibited chitin degradation and electrochemical activity, respectively. When co-cultured in an bioelectrochemical reactor, the acetate produced by Vallitalea sp. during chitin degradation fueled Trichloromonas sp., which facilitated EET, hereby demonstrating that syntrophic interactions are used to couple anoxic chitin degradation to EET in deep-sea sediments. These findings exemplify the interspecies interactions and resource optimization occurring in hard-to-reach and largely unknown deep-sea ecosystems.
]]></description>
<dc:creator>Jangir, Y.</dc:creator>
<dc:creator>Guo, Y.</dc:creator>
<dc:creator>Connon, S.</dc:creator>
<dc:creator>Pontrelli, S.</dc:creator>
<dc:creator>Wu, F.</dc:creator>
<dc:creator>Schwartzman, J.</dc:creator>
<dc:creator>Lim, S.</dc:creator>
<dc:creator>Sauer, U.</dc:creator>
<dc:creator>Cordero, O. X.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2025-06-30</dc:date>
<dc:identifier>doi:10.1101/2025.06.30.662270</dc:identifier>
<dc:title><![CDATA[Deep sea anaerobic microbial community couples the degradation of insoluble chitin to extracellular electron transfer]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.02.662771v1?rss=1">
<title>
<![CDATA[
Two parallel lineage-committed progenitors contribute to the developing brain 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.02.662771v1?rss=1</link>
<description><![CDATA[
The hindbrain is a life-sustaining brain region. In one model, a common neural progenitor generates all brain regions. Here our studies of mouse embryos and human pluripotent stem cells (hPSCs) support a different model: two parallel brain progenitors emerge simultaneously during gastrulation, anterior neural ectoderm (forebrain/midbrain progenitor) and posterior neural ectoderm (hindbrain progenitor). Not only are they lineage-committed to respectively form forebrain/midbrain vs. hindbrain in vitro, but they also have diverging chromatin landscapes foreshadowing future forebrain/midbrain vs. hindbrain identities. Leveraging these differences, we differentiated hPSCs into hindbrain rhombomere 5/6-specific motor neurons, hitherto difficult to generate in vitro. We postulate the brain is a composite organ emanating from two lineage-restricted progenitors; these dual progenitors may be evolutionarily conserved across 550 million years from hemichordates to mammals.
]]></description>
<dc:creator>Dundes, C. E.</dc:creator>
<dc:creator>Jokhai, R. T.</dc:creator>
<dc:creator>Ahsan, H.</dc:creator>
<dc:creator>Kang, R. S.</dc:creator>
<dc:creator>Salomon-Shulman, R. E. A.</dc:creator>
<dc:creator>Rajan, A.</dc:creator>
<dc:creator>Kim, Y. S.</dc:creator>
<dc:creator>Stanton, L. J.</dc:creator>
<dc:creator>Xu, C.</dc:creator>
<dc:creator>Do, S.</dc:creator>
<dc:creator>McDonald, B. D.</dc:creator>
<dc:creator>Lopez, J. M. A.</dc:creator>
<dc:creator>Urrutia, H. A.</dc:creator>
<dc:creator>Greenfeld, H.</dc:creator>
<dc:creator>Wong, A.</dc:creator>
<dc:creator>Qu, Y.</dc:creator>
<dc:creator>Petkovic, A. S.</dc:creator>
<dc:creator>Miao, Y.</dc:creator>
<dc:creator>Garcia, K. C.</dc:creator>
<dc:creator>Monje, M.</dc:creator>
<dc:creator>Wagner, D. E.</dc:creator>
<dc:creator>Bronner, M. E.</dc:creator>
<dc:creator>Lowe, C. J.</dc:creator>
<dc:creator>Loh, K. M.</dc:creator>
<dc:date>2025-07-03</dc:date>
<dc:identifier>doi:10.1101/2025.07.02.662771</dc:identifier>
<dc:title><![CDATA[Two parallel lineage-committed progenitors contribute to the developing brain]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.02.662832v1?rss=1">
<title>
<![CDATA[
Symbiotic entrenchment through ecological Catch-22 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.02.662832v1?rss=1</link>
<description><![CDATA[
Symbiotic organisms frequently evolve obligate dependencies on hosts, but the evolutionary changes that entrench such lifestyles are poorly understood. Ant societies are vulnerable to parasitic "myrmecophiles": impostor species that infiltrate colonies and are often unable to survive outside of them. Here we show that obligate dependence of a myrmecophile on its host arises from irreversibility of the fundamental steps that achieve social acceptance inside the nest. We report a convergent system in which parallel rove beetle lineages (Staphylinidae) evolved from free-living ancestors to parasitize the same host ant. Exploiting this system, we uncover cellular mechanisms by which these beetles mimic host ant cuticular hydrocarbons (CHCs): nestmate recognition pheromones, which function pleiotropically to prevent desiccation. We present evidence of a biological stealth mechanism in a rove beetle in which the CHC biosynthetic machinery becomes transcriptionally silenced on entering the nest. Silencing transforms the beetle into a chemical blank slate onto which ant CHCs are horizontally transferred via interspecies grooming behavior. This strategy leads to identical chemical resemblance and seamless social integration within the colony. CHC pathway silencing is irreversible, however, forcing the beetle into a chronic, physically close dependence on ants to both maintain nestmate status and prevent desiccation. Loss of CHC silencing renders the beetle detectable to ants; conversely, loss of behavioral attraction to ants renders the beetle desiccation prone. Our findings show how symbiotic entrenchment can arise from a Catch-22-like ratchet operating at the organismal level.
]]></description>
<dc:creator>Naragon, T. H.</dc:creator>
<dc:creator>Viliunas, J. W.</dc:creator>
<dc:creator>Yousefelahiyeh, M.</dc:creator>
<dc:creator>Bruckner, A.</dc:creator>
<dc:creator>Wagner, J. M.</dc:creator>
<dc:creator>Ryon, H. M.</dc:creator>
<dc:creator>Collinson, D.</dc:creator>
<dc:creator>Kitchen, S. A.</dc:creator>
<dc:creator>Wijker, R. S.</dc:creator>
<dc:creator>Sessions, A. L.</dc:creator>
<dc:creator>Parker, J.</dc:creator>
<dc:date>2025-07-03</dc:date>
<dc:identifier>doi:10.1101/2025.07.02.662832</dc:identifier>
<dc:title><![CDATA[Symbiotic entrenchment through ecological Catch-22]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.06.30.662484v1?rss=1">
<title>
<![CDATA[
Models and Algorithms for Equilibrium Analysis of Mixed-Material Nucleic Acid Systems 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.06.30.662484v1?rss=1</link>
<description><![CDATA[
Dynamic programming algorithms within the NUPACK software suite enable analysis of equilibrium base-pairing properties for complex and test tube ensembles containing arbitrary numbers of interacting nucleic acid strands. Currently, calculations are limited to single-material systems that are either all-RNA or all-DNA. Here, to enable analysis of mixed-material systems that are critical for modern applications in vitro, in situ, and in vivo, we develop physical models and dynamic programming algorithms that allow the material of the system to be specified at nucleotide resolution. Free energy parameter sets are constructed for both RNA/DNA and RNA/2'OMe-RNA mixed-material systems by combining available empirical mixed-material parameters with single-material parameter sets to enable treatment of the full complex and test tube ensembles. New dynamic programming recursions account for the material of each nucleotide throughout the recursive process. For a complex with N nucleotides, the mixed-material dynamic programming algorithms maintain the O(N 3) time complexity of the single-material algorithms, enabling efficient calculation of diverse physical quantities over complex and test tube ensembles (e.g., complex partition function, equilibrium complex concentrations, equilibrium base-pairing probabilities, minimum free energy secondary structure(s), and Boltzmann-sampled secondary structures) at a cost increase of roughly 2.0-3.5x . The results of existing single-material algorithms are exactly reproduced when applying the new mixed-material algorithms to single-material systems. Accuracy is significantly enhanced using mixed-material models and algorithms to predict RNA/DNA and RNA/2'OMe-RNA duplex melting temperatures from the experimental literature as well as RNA/DNA melt profiles from new experiments. Mixed-material analyses can be performed online using the NUPACK web app (www.nupack.org) or locally using the NUPACK Python module.{paragraph}



O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=183 SRC="FIGDIR/small/662484v1_ufig1.gif" ALT="Figure 1">
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]]></description>
<dc:creator>Nanjundiah, A.</dc:creator>
<dc:creator>Fornace, M. E.</dc:creator>
<dc:creator>Schulte, S. J.</dc:creator>
<dc:creator>Pierce, N. A.</dc:creator>
<dc:date>2025-07-04</dc:date>
<dc:identifier>doi:10.1101/2025.06.30.662484</dc:identifier>
<dc:title><![CDATA[Models and Algorithms for Equilibrium Analysis of Mixed-Material Nucleic Acid Systems]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.03.663106v1?rss=1">
<title>
<![CDATA[
Association of E. coli Nissle with insect-parasitic nematode Steinernema hermaphroditum 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.03.663106v1?rss=1</link>
<description><![CDATA[
Steinernema species are soil-dwelling and insect-parasitic nematodes that associate with symbiotic Xenorhabdus bacteria. During the infective juvenile (IJ) stage, Steinernema nematodes package species-specific Xenorhabdus bacteria in the anterior intestinal pockets. The nematodes can survive in the soil for months as they seek insect prey. The mechanisms of how these nematodes associate with environmental microbes other than their Xenorhabdus symbionts is barely known. Here, we report a new mechanism of E. coli Nissle (EcN) association with the nematode Steinernema hermaphroditum. We show that EcN cells are enclosed and lysed in at least four pairs of coelomocytes, suggesting these immune cells respond to bacterial invasion. During the IJ stage of nematode development, EcN cells localize to posterior intestinal vacuoles and enter the inter-cuticular space, where they proliferate, aggregate, then lyse. EcN cells expressed proteins in the cell lysates were maintained in the nematode cuticle over eight weeks in non-sterile soil. These observations suggest sequential steps of EcN colonization in the host nematodes involving an immune response that is distinctive from interactions with mutualistic symbiont. Our work establishes a novel framework of nematode-bacteria interaction with potential applications in environmental bioengineering.
]]></description>
<dc:creator>Chen, V.</dc:creator>
<dc:creator>Marken, J. P.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:creator>Cao, M.</dc:creator>
<dc:date>2025-07-04</dc:date>
<dc:identifier>doi:10.1101/2025.07.03.663106</dc:identifier>
<dc:title><![CDATA[Association of E. coli Nissle with insect-parasitic nematode Steinernema hermaphroditum]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.06.663365v1?rss=1">
<title>
<![CDATA[
Ultrasound imaging of in situ transcriptional activity in opaque tissue 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.06.663365v1?rss=1</link>
<description><![CDATA[
Ultrasound imaging and acoustic reporter genes provide unique capabilities for in vivo biological imaging by leveraging ultrasounds ability to visualize opaque tissues with high spatiotemporal resolution. But until now, the expression of acoustic reporter genes - based on gas vesicle (GV) proteins - has been limited to ex vivo-modified cells due to the complexity of the GV gene cluster, precluding valuable in situ applications. Here, we develop a system capable of introducing GV genes directly into native tissues via stoichiometric multi-AAV delivery. We validate this system in the mouse brain, demonstrating well-tolerated in situ gene expression and repeated ultrasound imaging over more than a month in the same animal. Furthermore, by placing GV genes under the control of immediate early gene promoters, we demonstrate the ability to track in vivo gene expression changes arising from elevated neural activity during epileptic seizures. This work connects ultrasound to in situ transcriptional dynamics happening inside the opaque tissues of living creatures.
]]></description>
<dc:creator>Shivaei, S.</dc:creator>
<dc:creator>Cheung, K. Y. M.</dc:creator>
<dc:creator>Yadav, A.</dc:creator>
<dc:creator>Hurvitz, I. U.</dc:creator>
<dc:creator>Lee, S.</dc:creator>
<dc:creator>Revilla, J.</dc:creator>
<dc:creator>Rabut, C.</dc:creator>
<dc:creator>Criado-Hidalgo, E.</dc:creator>
<dc:creator>Zhang, R. J.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2025-07-07</dc:date>
<dc:identifier>doi:10.1101/2025.07.06.663365</dc:identifier>
<dc:title><![CDATA[Ultrasound imaging of in situ transcriptional activity in opaque tissue]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.13.664612v1?rss=1">
<title>
<![CDATA[
An Automated End-to-End Workflow for Production of Secreted Proteins in Transfected Mammalian Cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.13.664612v1?rss=1</link>
<description><![CDATA[
The advancement of automation technologies has helped to enable a surge in large-scale screening efforts across fields such as molecular biology, protein biochemistry, cell biology, and structural biology. In the context of this "omics"-driven research, there is a need to generate automation platforms that are more flexible and less expensive, so that they can be utilized for basic research conducted by small groups. A key challenge in automation lies in developing methods that can replicate fine motor techniques that are normally performed manually by researchers at the bench. We are engaged in a large-scale project to map interactions among human cell-surface and secreted proteins and assess their effects on cells. This project involves production of a library of more than 2000 recombinant His-tagged fusion proteins secreted from transfected Expi293 cells. To execute such a project with a small group at an academic institution required construction of an affordable automated system that could also be used by other investigators. This led us to develop a high-throughput, 96-well format automation platform for end-to-end protein production. The workflow includes transformation of E. coli, plasmid DNA preparation, transient transfection, protein purification, desalting and buffer exchange, protein quantification, and normalization of protein concentrations, resulting in assay-ready proteins. The system is built around an in-house engineered modular robotic platform that integrates liquid handling with a suite of interchangeable  plug-and-play mobile enclosed device modules. Housed within a BSL-2 sterile environment, the platform enables flexible, fully automated workflows and can be readily customized for diverse user-defined protocols.
]]></description>
<dc:creator>Vasnarungruengkul, P.</dc:creator>
<dc:creator>Anaya, M. A.</dc:creator>
<dc:creator>Lam, A. W.</dc:creator>
<dc:creator>Gonzalez, E.</dc:creator>
<dc:creator>Zhang, A.</dc:creator>
<dc:creator>Wang, M. L.</dc:creator>
<dc:creator>Wojtowicz, W.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:creator>Vielmetter, J.</dc:creator>
<dc:date>2025-07-13</dc:date>
<dc:identifier>doi:10.1101/2025.07.13.664612</dc:identifier>
<dc:title><![CDATA[An Automated End-to-End Workflow for Production of Secreted Proteins in Transfected Mammalian Cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.09.663943v1?rss=1">
<title>
<![CDATA[
A multiplex extracellular interactome screening method employing high-avidity nanoparticles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.09.663943v1?rss=1</link>
<description><![CDATA[
Metazoan cells signal to each other via direct contact between cell surface proteins (CSPs) and by interactions of CSP receptors with secreted ligands. CSP extracellular domain (ECD) interactions control organ development and physiology and are perturbed in disease states. However, because they cannot be accurately assessed using standard high-throughput screening techniques, they are underrepresented in protein interaction databases. Many ECD interactions are of low affinity, and their detection in vitro requires taking advantage of avidity effects, typically by multimerization of fusion proteins. Assays that test only one or a few interactions in each binding reaction are inadequate for global interactome screening. Here we describe a new multiplex method that uses purified dimeric ECD fusion proteins coupled to 60-mer nanoparticles as soluble prey, and the same dimers coupled to spectrally distinguishable fluorescent microspheres (beads) as bait. We add one prey to a mixture of up to 500 baits in a single well, then use a Luminex FLEXMAP 3D (FM3D) instrument to read out bait identity and prey binding. The FM3D measures the fluorescent dye ratio for each bead and simultaneously determines the amount of epitope-tagged prey bound to that bead. We use the method, denoted as the Multiplex Interactome Assay (MPIA), to analyze a proof-of-concept (PoC) set of 41 CSPs and secreted protens that is derived from larger collections examined in two interactome screens that used ELISA-based binding assays. By analyzing interactions among PoC proteins, we compared the MPIA with earlier screening methods. The MPIA has a dynamic range that is at least 30-fold greater than ELISA-based assays and appears to be more sensitive. By coupling the MPIA to an automated protein production and purification platform, we hope to be able to conduct a screen for interactions among thousands of human CSPs and secreted ligands.
]]></description>
<dc:creator>Anaya, M.</dc:creator>
<dc:creator>Wang, M. L.</dc:creator>
<dc:creator>Gonzalez, E.</dc:creator>
<dc:creator>Lam, A. W.</dc:creator>
<dc:creator>Vasnarungruengkul, P.</dc:creator>
<dc:creator>Vielmetter, J.</dc:creator>
<dc:creator>Wojtowicz, W. M.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:date>2025-07-14</dc:date>
<dc:identifier>doi:10.1101/2025.07.09.663943</dc:identifier>
<dc:title><![CDATA[A multiplex extracellular interactome screening method employing high-avidity nanoparticles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.11.664421v1?rss=1">
<title>
<![CDATA[
Transcriptomic responses to endurance exercise training in rats 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.11.664421v1?rss=1</link>
<description><![CDATA[
The bio-molecular changes of exercise, and how to best optimize them for improved performance, are an important human health research question. A recent study by the Molecular Transducers of Physical Activity Consortium (MoTrPAC) used a cohort of Rattus norvegicus to produce a whole-organism molecular map of the temporal effects of endurance exercise training. This dataset, encompassing hundreds of assays across 19 different tissues, can be used to evaluate the predictive power of gene expression, understand isoform-level changes in response to exercise, and with modern tools can be examined for associations with viral infection. Our analysis of the RNA-seq data reveals that gene expression can accurately predict the amount of exercise a rat was trained in. Additionally, we find biologically relevant isoform-level differences in expression that are masked in gene-level analysis. Finally, we find a potential novel virus that may negatively impact physiological measurements. This more comprehensive analysis provides a blueprint for directing similar analyses with respect to physiological perturbations across organisms.
]]></description>
<dc:creator>Oakes, C. G.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2025-07-17</dc:date>
<dc:identifier>doi:10.1101/2025.07.11.664421</dc:identifier>
<dc:title><![CDATA[Transcriptomic responses to endurance exercise training in rats]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.16.664392v1?rss=1">
<title>
<![CDATA[
Genetically encoded assembly recorder temporally resolves cellular histories in cellulo and in vivo 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.16.664392v1?rss=1</link>
<description><![CDATA[
Mapping cellular activity with high spatiotemporal precision in complex tissues is essential for understanding organ physiology, pathology, and regenerative processes. Here, we introduce Granularly Expanding Memory for Intracellular Narrative Integration (GEMINI), an in cellulo recording platform that leverages a computationally designed protein assembly as an intracellular memory device to record individual cells activity histories. GEMINI grows predictably within live cells with minimal interference to cellular functions, capturing cellular activities as tree-ring-like fluorescent patterns in the expanding scaffolds for imaging-based retrospective readout. Absolute chronological information of activity histories was attainable with hour-level accuracy through the integration of fiducial timestamps. GEMINI effectively resolved differential NF{kappa}B-mediated transcriptional changes, distinguishing fast dynamics of 15 minutes, and providing quantifiable signal amplitudes. In a xenograft model, GEMINI recorded inflammation-induced signaling dynamics across tissue with cellular resolution, revealing spatial heterogeneity linked to vascular density. When expressed in the mouse brain, GEMINI exhibited negligible impact on neuronal survival, with animals maintaining normal motor and cognitive behaviors. In physiological contexts, GEMINI successfully resolved both transcriptional changes and activity patterns of neurons in the brain. Together, GEMINI provides a robust and generalizable means for spatiotemporal mapping of cell dynamics underlying physiological and pathological processes in both culture and intact tissues.
]]></description>
<dc:creator>Yan, Y.</dc:creator>
<dc:creator>Lu, J.</dc:creator>
<dc:creator>Li, Z.</dc:creator>
<dc:creator>Zhao, Z.-H.</dc:creator>
<dc:creator>Shay, T. F.</dc:creator>
<dc:creator>Wang, S.</dc:creator>
<dc:creator>Lei, Y.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Chen, W.</dc:creator>
<dc:creator>Parker, P.</dc:creator>
<dc:creator>Yang, H.</dc:creator>
<dc:creator>Qi, A.</dc:creator>
<dc:creator>Sun, Y.</dc:creator>
<dc:creator>Bergles, D.</dc:creator>
<dc:creator>Baker, D.</dc:creator>
<dc:creator>Lin, D.</dc:creator>
<dc:date>2025-07-18</dc:date>
<dc:identifier>doi:10.1101/2025.07.16.664392</dc:identifier>
<dc:title><![CDATA[Genetically encoded assembly recorder temporally resolves cellular histories in cellulo and in vivo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.17.665311v1?rss=1">
<title>
<![CDATA[
Mapping the Exit Route of Hydrogen Peroxide From the Manganese Superoxide Dismutase (MnSOD) Active Site. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.17.665311v1?rss=1</link>
<description><![CDATA[
Human mitochondrial manganese superoxide dismutase (MnSOD) converts superoxide (O [bullet]-) into hydrogen peroxide (H O ) and molecular oxygen (O ), serving as a key defense against oxidative damage. Despite extensive studies, the full structural characterization of H2O2-binding sites in MnSOD remains largely unexplored. Previous H2O2-soaked MnSOD structures have identified two distinct H2O2-binding sites: one directly ligated to the catalytic Mn (LIG position) and another at the active site gateway (PEO position) between second-shell residues Tyr34 and His30. In this study, a kinetically impaired Gln143Asn MnSOD variant is used to trap and explore additional H2O2-binding sites beyond the second-shell solvent gate. In the wild-type enzyme, Gln143 mediates proton transfers with the Mn-bound solvent (WAT1) to drive redox cycling of the metal, necessary for effective O [bullet]- dismutation. Substitution with Asn stalls catalysis because the increased distance from WAT1 disrupts critical proton-coupled electron transfer (PCET) events, and the redox cycling of the active site metal is impaired. This, in turn, stalls the electrostatic cycling of positive charge on the enzyme surface and enhances the likelihood of trapping transient H2O2-bound states in this variant. Results reveal several H2O2 molecules leading up to the active site, in addition to the canonical LIG and PEO positions.

SynopsisA high-resolution X-ray structure of a Gln143Asn variant of manganese superoxide dismutase reveals multiple hydrogen peroxide binding sites beyond the canonical LIG and PEO binding positions within the active site. These findings expand the known landscape of product peroxide-bound states in MnSOD.
]]></description>
<dc:creator>Borgstahl, G. E.</dc:creator>
<dc:creator>DASGUPTA, M.</dc:creator>
<dc:creator>Slobodnik, K.</dc:creator>
<dc:creator>Cone, E.</dc:creator>
<dc:creator>Kroll, T.</dc:creator>
<dc:creator>Azadmanesh, J.</dc:creator>
<dc:date>2025-07-19</dc:date>
<dc:identifier>doi:10.1101/2025.07.17.665311</dc:identifier>
<dc:title><![CDATA[Mapping the Exit Route of Hydrogen Peroxide From the Manganese Superoxide Dismutase (MnSOD) Active Site.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.16.665256v1?rss=1">
<title>
<![CDATA[
The History of Enzyme Evolution Embedded in Metabolism 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.16.665256v1?rss=1</link>
<description><![CDATA[
Whereas phylogenetic reconstructions are a primary record of protein evolution, it is unknown whether the deep history of enzymes are encoded at higher levels of biological organization. Here, we demonstrate that the emergence and reuse history of enzymatic folds is embedded within the web of metabolite-cofactor-enzyme interdependencies that comprise biosphere-scale metabolic reaction networks. Using a simple network analysis approach, we reconstruct the relative ordering of enzymatic fold emergence and, where possible, the first reaction(s) that each enzymatic fold catalyzed. We find that a large majority of enzymatic folds were sufficient as independent additions to open new avenues for metabolic growth. The resulting network-based histories are broadly concordant with enzyme phyletic distribution in prokaryotes, a proxy for enzyme age. Our results suggest that the earliest enzyme-mediated metabolisms were enriched for /{beta} proteins, likely due to their strong association with cofactor utilization, and that -proteins preferentially emerge at later stages. The cradle-loop barrel, a member of the small {beta}-barrel metafold, is predicted to be the founding {beta}-fold, in agreement with analyses of ribosome structure. An examination of how the protein universe responded to the biological production of molecular oxygen reveals that the adaptation of existing enzymatic folds, not novel fold emergence, was the primary driver of metabolic evolution. This work presents a self-consistent model of metabolic and enzyme evolution, key progress towards integrating diverse perspectives into a unified history of protein evolution.

Significance StatementEnzyme emergence is an ongoing process that began [~]4 billion years ago. Here, we show that the modern biosphere-scale network of metabolic reactions and enzymes is an archive of enzyme history independent from, but concordant with, phylogenetics. Based on this record, we predict the order of enzyme emergence from before the last universal common ancestor up until the biological production and metabolic utilization of molecular oxygen. We find that while /{beta} proteins dominated primitive enzyme-mediated metabolism, other folds -- including the cradle-loop barrel, which is a member of the small {beta}-barrel metafold -- were likely important early contributors. This study represents key progress towards building an internally consistent, joint history of metabolic reactions and enzymes.
]]></description>
<dc:creator>Corlett, T.</dc:creator>
<dc:creator>Smith, H. B.</dc:creator>
<dc:creator>Smith, E.</dc:creator>
<dc:creator>Goldford, J.</dc:creator>
<dc:creator>Longo, L. M.</dc:creator>
<dc:date>2025-07-21</dc:date>
<dc:identifier>doi:10.1101/2025.07.16.665256</dc:identifier>
<dc:title><![CDATA[The History of Enzyme Evolution Embedded in Metabolism]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.20.664993v1?rss=1">
<title>
<![CDATA[
Viral communities from long-term anaerobic alkane-oxidizing enrichments may promote cell surface adhesion 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.20.664993v1?rss=1</link>
<description><![CDATA[
The anaerobic oxidation of methane and higher C2+ alkanes is a dominant metabolism within hydrocarbon-rich deep-sea sediments and is largely mediated by alkane-oxidizing archaea in metabolic partnership with syntrophic sulfate-reducing bacteria. While these processes feed a diverse ecosystem, the viral component of alkane-rich sediments has historically been overlooked. We analyzed the viral community in long-term sediment-free enrichments of alkane-degrading organisms and found that abiotic factors such as incubation temperature had a greater correlation with community composition than with the phylogenetic patterns among individual viral species. No auxiliary metabolic genes directly involved in hydrocarbon oxidation or sulfate reduction were found, but the presence of AMGs involved in heme synthesis pathways common in methane oxidizers hints at a possible viral impact on alkane degradation. We also found evidence supporting the presence of a viral genus infecting several phyla across both the bacterial and archaeal domains, including one of the sulfate-reducing bacterial partners in the alkane-oxidizing syntrophy. Lastly, we report the presence of nosD-like proteins in viruses from sediment-derived systems that are not present in water column datasets; their distribution, genomic context, and lack of canonical nosD characteristics suggest an alternate adhesion-related role in sediment communities. The number of novel viruses obtained from these enrichment cultures and their potential roles in mediating host physiology illustrate the importance of studying the viral component in laboratory and environmental systems.
]]></description>
<dc:creator>Narayanan, A. K.</dc:creator>
<dc:creator>Philosof, A.</dc:creator>
<dc:creator>Murali, R.</dc:creator>
<dc:creator>Connon, S. A.</dc:creator>
<dc:creator>Wegener, G.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2025-07-21</dc:date>
<dc:identifier>doi:10.1101/2025.07.20.664993</dc:identifier>
<dc:title><![CDATA[Viral communities from long-term anaerobic alkane-oxidizing enrichments may promote cell surface adhesion]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.18.665560v1?rss=1">
<title>
<![CDATA[
Food-activated Microneedle Sensor for Real-time, Colorimetric Spoilage Monitoring of Pre-packaged Food 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.18.665560v1?rss=1</link>
<description><![CDATA[
At a time of growing food insecurity, developing technologies to reduce food waste is critical. We report an inexpensive, colorimetric spoilage sensor for real-time food product assessment. The sensor is composed of dehydrated gelatin microneedles that exhibit high mechanical integrity in their base state. However, once exposed to fluid-rich food environments, they rapidly transition to a hydrogel sensing state. Food-derived anthocyanins embedded within these microneedles enable pH-based spoilage monitoring. When applied to sealed fish products, these microneedles non-destructively penetrate through packaging and are rehydrated by the underlying fish matrix. As the product ages, a defined colour shift occurs, demonstrating strong correlation with quantitative spoilage markers. When applied to unsealed fish products for rapid testing, the large microneedle sensing interface enables accelerated colorimetric sensing. Finally, successful fresh versus spoiled categorization of smartphone-acquired images of the sensor using machine learning removes readout ambiguity, empowering consumers with independent real-time product monitoring.
]]></description>
<dc:creator>Khan, S.</dc:creator>
<dc:creator>Prasad, A.</dc:creator>
<dc:creator>Javed, M.</dc:creator>
<dc:creator>Maclachlan, R.</dc:creator>
<dc:creator>Filipe, C. D. M.</dc:creator>
<dc:creator>Didar, T.</dc:creator>
<dc:date>2025-07-22</dc:date>
<dc:identifier>doi:10.1101/2025.07.18.665560</dc:identifier>
<dc:title><![CDATA[Food-activated Microneedle Sensor for Real-time, Colorimetric Spoilage Monitoring of Pre-packaged Food]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.21.665910v1?rss=1">
<title>
<![CDATA[
Harmonic Amplitude-Modulated Singular Value Decomposition for Ultrafast Ultrasound Imaging of Gas Vesicles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.21.665910v1?rss=1</link>
<description><![CDATA[
Ultrafast nonlinear ultrasound imaging of gas vesicles (GV) contrast agents promises high-sensitivity biomolecular visualization with applications such as targeted molecular imaging of tumor markers or real-time tracking of gene expression. However, separating GV-specific signal from tissue remains challenging and requires the implementation of complex transmit schemes. In this work we introduce harmonic amplitude-modulated singular value decomposition (HAM-SVD), which synergizes pulse inversion (PI) with amplitude-modulated singular value decomposition (AM-SVD) to isolate GV-specific second-harmonic signals. In HAM-SVD, single-cycle plane waves at 9.6 MHz and five tilted angles (at a pulse repetition frequency of 2500 Hz) are transmitted under four duty cycles with alternating polarity. Beamformed IQ data are reshaped along a "space x pressure" matrix and decomposed via SVD; tissue background is cancelled by discarding the first and lowest singular modes, yielding an image comprised solely of pressure-dependent second harmonic signals. HAM-SVD sequence enables wide-field, ultrafast imaging without complex transmit sequences. Validation via simulations, in vitro phantoms, and in vivo rat lower limb experiments demonstrates HAM-SVDs outperformance compared to PI and AM-SVD. HAM-SVD is shown to achieve a 19.16 {+/-} 1.63 dB signal-to-background ratio (SBR) in vivo, surpassing PI (14.19 {+/-} 1.41 dB) and AM-SVD (15.79 {+/-} 1.38 dB). HAM-SVD overcomes limitations of conventional nonlinear techniques (e.g., depth restrictions, tissue clutter) by combining PIs harmonic sensitivity with AM-SVDs adaptive clutter filtering of tissue signals. This approach enhances molecular imaging specificity for GVs and holds potential for ultrasound localization microscopy of slow-flowing agents.
]]></description>
<dc:creator>Zhang, G.</dc:creator>
<dc:creator>Leroy, H.</dc:creator>
<dc:creator>Haidour, N.</dc:creator>
<dc:creator>Rivera, E.</dc:creator>
<dc:creator>Zucker, N.</dc:creator>
<dc:creator>Nouhoum, M.</dc:creator>
<dc:creator>Jimenez, A.</dc:creator>
<dc:creator>Deffieux, T.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Nayak, R.</dc:creator>
<dc:creator>Pezet, S.</dc:creator>
<dc:creator>Shapiro, M.</dc:creator>
<dc:creator>Pernot, M.</dc:creator>
<dc:creator>Tanter, M.</dc:creator>
<dc:date>2025-07-24</dc:date>
<dc:identifier>doi:10.1101/2025.07.21.665910</dc:identifier>
<dc:title><![CDATA[Harmonic Amplitude-Modulated Singular Value Decomposition for Ultrafast Ultrasound Imaging of Gas Vesicles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.25.666579v1?rss=1">
<title>
<![CDATA[
Growth Cost and Transport Efficiency Tradeoffs Define Root System Optimization Across Varying Developmental Stages and Environments in Arabidopsis 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.25.666579v1?rss=1</link>
<description><![CDATA[
Root system architecture (RSA) is central to plant adaptation and fitness, yet the design principles and regulatory mechanisms connecting RSA to environmental adaptation are not well understood. We developed Ariadne, a semi-automated software for quantifying cost-efficiency tradeoffs of RSA by mapping root networks onto a Pareto-optimality framework, which describes the balance between resource transport efficiency and construction cost. Applying Ariadne to Arabidopsis thaliana, we found that root architectures consistently assume Pareto-optimal forms across developmental stages, genotypes, and environmental conditions. Using the Discovery Engine, an engine that combines machine learning together with interpretability techniques, we found developmental stage, the hy5/chl1-5 genotype, and manganese availability as important determinants of the cost-efficiency tradeoff, with manganese exerting a unique influence not observed for other nutrients. These results reveal that RSA plasticity is genetically constrained to cost-efficiency optimal configurations and that developmental and environmental factors shift RSA on the pareto front, with manganese acting as a strong modulator of the transport efficiency and construction cost balance.
]]></description>
<dc:creator>Faizi, K.</dc:creator>
<dc:creator>Mehta, P.</dc:creator>
<dc:creator>Maida, A.</dc:creator>
<dc:creator>Humphreys, T.</dc:creator>
<dc:creator>Berrigan, E.</dc:creator>
<dc:creator>McKee-Reid, L.</dc:creator>
<dc:creator>McCorkell, R.</dc:creator>
<dc:creator>Tagade, A.</dc:creator>
<dc:creator>Rumbelow, J.</dc:creator>
<dc:creator>Showalter, J.</dc:creator>
<dc:creator>Brent, L.</dc:creator>
<dc:creator>Coroenne, C.</dc:creator>
<dc:creator>Rigaud, A.</dc:creator>
<dc:creator>Chandrasekhar, A.</dc:creator>
<dc:creator>Navlakha, S.</dc:creator>
<dc:creator>Martin, A.</dc:creator>
<dc:creator>Pradal, C.</dc:creator>
<dc:creator>Lee, S.</dc:creator>
<dc:creator>Busch, W.</dc:creator>
<dc:creator>Platre, M. P.</dc:creator>
<dc:date>2025-07-26</dc:date>
<dc:identifier>doi:10.1101/2025.07.25.666579</dc:identifier>
<dc:title><![CDATA[Growth Cost and Transport Efficiency Tradeoffs Define Root System Optimization Across Varying Developmental Stages and Environments in Arabidopsis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.25.666871v1?rss=1">
<title>
<![CDATA[
Dynamic Reworking of Marine Diatom Endometabolomes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.25.666871v1?rss=1</link>
<description><![CDATA[
A large annual carbon flux occurs through the oceans labile dissolved organic carbon (DOC) pool, with carbon influx dominated by phytoplankton-derived metabolites and outflux by heterotrophic bacterioplankton uptake. We addressed the dynamics of this flux between marine primary and secondary producers through analysis of the Thalassiosira pseudonana CCMP1335 endometabolome, a proxy for labile DOC release during phytoplankton excretion and mortality. Diatom strains acclimated at one of three different temperatures (14{degrees}C, 20{degrees}C, or 28{degrees}C) were then cultured either axenically or with the bacterium Ruegeria pomeroyi DSS-3, and their endometabolites analyzed by NMR. Osmolytes were by far the most dynamic, exhibiting concentration differences up to 150-fold between conditions; median concentration variation across identified endometabolites was [~]1.5-fold. Differential expression of diatom metabolic pathways suggested changes in synthesis rates as a mechanism for endometabolome remodeling. Consistent with expectations of high turnover, endometabolite mean lifetimes prior to bacterial uptake were <2 h to 12 h.

ImportanceThe role of labile DOC in the transfer of marine carbon between phytoplankton and heterotrophic bacteria was first recognized 40 years ago, yet the identity and dynamics of phytoplankton metabolites entering the labile DOC pool are still poorly known. Using metabolome and transcriptome profiling, we found dynamic composition and concentration of diatom endometabolites, depending on growth conditions and arising over time frames as short as a single growth cycle. This strong response to external conditions, both biotic and abiotic, has implications for downstream processing and fate of ocean carbon by heterotrophic bacteria.
]]></description>
<dc:creator>Olofsson, M.</dc:creator>
<dc:creator>Uchimiya, M.</dc:creator>
<dc:creator>Ferrer-Gonzalez, F. X.</dc:creator>
<dc:creator>Schreier, J. E.</dc:creator>
<dc:creator>Powers, M. A.</dc:creator>
<dc:creator>Smith, C. B.</dc:creator>
<dc:creator>Edison, A. S.</dc:creator>
<dc:creator>Moran, M. A.</dc:creator>
<dc:date>2025-07-31</dc:date>
<dc:identifier>doi:10.1101/2025.07.25.666871</dc:identifier>
<dc:title><![CDATA[Dynamic Reworking of Marine Diatom Endometabolomes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.07.29.667405v1?rss=1">
<title>
<![CDATA[
A molecular switch in NAC prevents mitochondrial protein mistargeting by SRP 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.07.29.667405v1?rss=1</link>
<description><![CDATA[
The nascent polypeptide-associated complex (NAC) co-translationally screens all nascent proteins and regulates their access to the signal recognition particle (SRP) to ensure the fidelity of protein targeting to the endoplasmic reticulum (ER). However, the mechanism by which NAC prevents the mistargeting of nascent mitochondrial proteins remains unclear. Here, we identified a molecular switch in NAC that allows its central barrel domain to adopt a stabilized conformation on ribosomes exposing a mitochondrial targeting sequence (MTS). Mutations of the MTS on the nascent chain or in the NAC switch region increases NAC barrel dynamics and reduces its binding to the ribosome. This leads to an impaired ability of NAC to prevent mistargeting by SRP and causes ER stress in human cells. Our work reveals how NAC detects nascent mitochondrial proteins early in translation and prevents their promiscuous access to SRP, elucidating the structural basis that underlies this role and providing novel insights into protein targeting fidelity with broader implications for cellular proteostasis.
]]></description>
<dc:creator>Maldosevic, E.</dc:creator>
<dc:creator>Gora, R.</dc:creator>
<dc:creator>Lin, L. L.</dc:creator>
<dc:creator>Zhou, L. E.</dc:creator>
<dc:creator>Li, Z. J.</dc:creator>
<dc:creator>Peskova, Y.</dc:creator>
<dc:creator>Qi, L.</dc:creator>
<dc:creator>Shan, S.-o.</dc:creator>
<dc:creator>Jomaa, A.</dc:creator>
<dc:date>2025-08-01</dc:date>
<dc:identifier>doi:10.1101/2025.07.29.667405</dc:identifier>
<dc:title><![CDATA[A molecular switch in NAC prevents mitochondrial protein mistargeting by SRP]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-08-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.02.668148v1?rss=1">
<title>
<![CDATA[
NAC promotes co-translational folding at the ribosomal tunnel exit 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.02.668148v1?rss=1</link>
<description><![CDATA[
The nascent polypeptide-associated complex (NAC) coordinates enzymatic modifications and membrane targeting of nascent chains during translation. While NACs function as a dynamic hub for other factors is well-established, its direct role in co-translational folding is unclear. By proteome-wide profiling NAC co-translational interactions in human cells, we found that NAC recognizes emerging segments enriched in hydrophobicity and -helical propensity, within folded domains of cytonuclear proteins. Single-molecule and structural analyses reveal that NAC, via its {beta}-barrel domain, dynamically interacts with nascent chains at the ribosomal tunnel exit and is capable of promoting on-pathway folding. Compartment-specific nascent chain interactions of NAC further elucidate its role in targeting to the endoplasmic reticulum and mitochondrial membrane protein biogenesis. Together, these findings show that NAC acts as a bona fide co-translational chaperone that facilitates early protein folding at the ribosomal tunnel exit, expanding its functional repertoire in protein biogenesis.
]]></description>
<dc:creator>Santos, J.</dc:creator>
<dc:creator>Gunnigmann, M.</dc:creator>
<dc:creator>Gora, R. J.</dc:creator>
<dc:creator>Iljina, M.</dc:creator>
<dc:creator>Predin, M.</dc:creator>
<dc:creator>Kotan, I. E.</dc:creator>
<dc:creator>De, P.</dc:creator>
<dc:creator>Choudhary, D.</dc:creator>
<dc:creator>Jang, J.</dc:creator>
<dc:creator>Tippmann, F.</dc:creator>
<dc:creator>Ban, N.</dc:creator>
<dc:creator>Tans, S. J.</dc:creator>
<dc:creator>Shan, S.-o.</dc:creator>
<dc:creator>Kramer, G.</dc:creator>
<dc:creator>Bukau, B.</dc:creator>
<dc:date>2025-08-02</dc:date>
<dc:identifier>doi:10.1101/2025.08.02.668148</dc:identifier>
<dc:title><![CDATA[NAC promotes co-translational folding at the ribosomal tunnel exit]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-08-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.05.666878v1?rss=1">
<title>
<![CDATA[
Illuminating the active virosphere with BONCAT and single virus genomic sequencing technologies 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.05.666878v1?rss=1</link>
<description><![CDATA[
Marine viruses impact biogeochemical cycles through cell lysis, releasing organic matter and nutrients that fuel ocean productivity. Identifying and quantifying the specific viruses active in these processes remains a priority in the field. Here, we introduce a click-chemistry method to fluorescently label, sort, and sequence the genomes of newly produced viral particles released from transcriptionally active host microbial cells, alongside the analysis of co-occurring inactive cells and viruses in environmental samples. This approach, called viral BONCAT-FACS, combines biorthogonal non-canonical amino acid tagging (BONCAT) with environmental sample incubation, followed by single-virus and single-cell sorting by flow cytometry (FACS). Genomic analysis of translationally-active cells and new viral progeny in coastal seawater incubations confirmed BONCAT labeling and successful sorting of diverse marine bacteria, microeukaryotic cells, and virioplankton, with stark differences in the predicted turnover of specific groups of infecting viruses, including Pelagiphages, Methylophages, a Flavobacteriales-associated novel "Far-T4" clade, algae-infecting giant NCLDV viruses, and parasitic virophages. Sequenced BONCAT-active cells showed a strong enrichment in viral contigs relative to the inactive cell fraction, suggestive of a large proportion of translationally-active virocells. This study illustrates the effectiveness of viral BONCAT-FACS for uncovering genome-resolved viral-host dynamics. By providing a direct approach for tracking active viral infections in natural environments, this method enhances our ability to investigate behavior and interactions of these nanoscale predators, expanding our understanding of their role in ecosystem dynamics.
]]></description>
<dc:creator>Alvarez-Sanchez, M.</dc:creator>
<dc:creator>Martinez-Hernandez, F.</dc:creator>
<dc:creator>Llorenc-Vicedo, A.</dc:creator>
<dc:creator>Vila-Nistal, M.</dc:creator>
<dc:creator>Philosof, A.</dc:creator>
<dc:creator>Narayanan, A. K.</dc:creator>
<dc:creator>Tijerina, J. C.</dc:creator>
<dc:creator>Martinez-Garcia, M.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2025-08-05</dc:date>
<dc:identifier>doi:10.1101/2025.08.05.666878</dc:identifier>
<dc:title><![CDATA[Illuminating the active virosphere with BONCAT and single virus genomic sequencing technologies]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-08-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.06.668980v1?rss=1">
<title>
<![CDATA[
A modular method for rapidly prototyping targeted gas vesicle protein nanoparticles 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.06.668980v1?rss=1</link>
<description><![CDATA[
Gas vesicles (GVs) are air-filled protein nanoparticles which are proving to be useful in a number of biomedical applications. We hypothesized that it could be possible to develop a modular method for creating rapidly prototyped GVs by modifying their surface chemistry to include targeting peptides in an orientation-specific manner. Here, we describe a modular method to create targeted GVs using His-tagged antibody fragments, ensuring that the antibody fragments are connected to the GV in an orientation-specific manner. This is achieved via the functionalization of the GVs with nickel-nitrilotriacetic acid (Ni-NTA) group. First, we validated that these functionalized GVs can bind His-tagged green fluorescent protein and characterized the particle size and surface charge of functionalized GVs. Then, GVs targeted to prostate-specific membrane antigen (PSMA) using a minibody were validated using a knockout validation in vitro.
]]></description>
<dc:creator>Vassallo, R.</dc:creator>
<dc:creator>Ling, B.</dc:creator>
<dc:creator>Criado-Hidalgo, E.</dc:creator>
<dc:creator>Robinson, N.</dc:creator>
<dc:creator>Schrunk, E.</dc:creator>
<dc:creator>Liu, A.</dc:creator>
<dc:creator>Daghlian, G.</dc:creator>
<dc:creator>Li, H. R.</dc:creator>
<dc:creator>Swift, M. B.</dc:creator>
<dc:creator>Mannar, D.</dc:creator>
<dc:creator>Malounda, D.</dc:creator>
<dc:creator>Goldenberg, S. L.</dc:creator>
<dc:creator>Salcudean, S. E.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:creator>Black, P. C.</dc:creator>
<dc:creator>Cox, M. E.</dc:creator>
<dc:date>2025-08-07</dc:date>
<dc:identifier>doi:10.1101/2025.08.06.668980</dc:identifier>
<dc:title><![CDATA[A modular method for rapidly prototyping targeted gas vesicle protein nanoparticles]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-08-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.10.669515v1?rss=1">
<title>
<![CDATA[
O-Acyltransferase Genes Involved in the Production of Volatile Sex Pheromones in Caenorhabditis elegans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.10.669515v1?rss=1</link>
<description><![CDATA[
Gene family expansions are critical for functional diversification, yet paralog contributions to metabolic pathways are often unclear. In Caenorhabditis, the expanded O-acyltransferase (OAC) family--enzymes that transfer acyl groups to hydroxylated substrates--remains poorly characterized despite having been implicated in lipid metabolism. Using CRISPR-Cas9 mutagenesis, behavioral assays, gas chromatographic-mass spectral (GC-MS) analyses, and metabolomics, we systematically analyzed 59 OAC-family protein-coding genes to define their roles in regulating signaling molecules. We found that four adjacent paralogs (oac-13, oac-16, oac-25, and oac-28) on chromosome I are required for synthesizing volatile sex pheromones (VSPs)--airborne signals critical for male mate-searching. Specifically, oac-13 and oac-16 are necessary for producing both major pheromone components, while the identical tandem paralogs oac-25 and oac-28 regulate the production of the later-eluting component in gas chromatography. Disruption of these genes reduced production of key pheromone components and impaired male attraction. Metabolomics revealed that oac-16 and other OACs also modulate synthesis and secretion of non-volatile ascaroside pheromones, indicating dual roles in chemical signaling. This work uncovers functional specialization within an expanded gene family, illustrating how redundancy and divergence enable adaptive evolution of communication systems.
]]></description>
<dc:creator>Wan, X.</dc:creator>
<dc:creator>Cohen, S. M.</dc:creator>
<dc:creator>Yu, Y.</dc:creator>
<dc:creator>Le, H. H.</dc:creator>
<dc:creator>Park, H.</dc:creator>
<dc:creator>Groaz, A.</dc:creator>
<dc:creator>Moreno, R.</dc:creator>
<dc:creator>Tan, M.</dc:creator>
<dc:creator>Gronquist, M. R.</dc:creator>
<dc:creator>Shinya, R.</dc:creator>
<dc:creator>Schroeder, F. C.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:date>2025-08-12</dc:date>
<dc:identifier>doi:10.1101/2025.08.10.669515</dc:identifier>
<dc:title><![CDATA[O-Acyltransferase Genes Involved in the Production of Volatile Sex Pheromones in Caenorhabditis elegans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-08-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.15.670201v1?rss=1">
<title>
<![CDATA[
Covalent Drug binding in Live Cells Monitored by Mid-IR Quantum Cascade Laser Spectroscopy: Photoactive Yellow Protein as a Model System 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.15.670201v1?rss=1</link>
<description><![CDATA[
The detection of drug-target interactions in live cells enables analysis of therapeutic compounds in a native cellular environment. Recent advances in spectroscopy and molecular biology have facilitated the development of genetically encoded vibrational probes like nitriles that can sensitively report on molecular interactions. Nitriles are powerful tools for measuring electrostatic environments within condensed media like proteins, but such measurements in live cells have been hindered by low signal-to-noise ratios. In this study, we design a spectrometer based on a double-beam quantum cascade laser (QCL)-based transmission infrared (IR) source with balanced detection that can significantly enhance sensitivity to nitrile vibrational probes embedded in proteins within cells compared to a conventional FTIR spectrometer. Using this approach, we detect small-molecule binding in E. coli, with particular focus on the interaction between para-coumaric acid (pCA) and nitrile-incorporated photoactive yellow protein (PYP). This system effectively serves as a model for investigating covalent drug binding in a cellular environment. Notably, we observe large spectral shifts of up to 15 cm-1 for nitriles embedded in PYP between the unbound and drug-bound states directly within bacteria, in agreement with observations for purified proteins. Such large spectral shifts are ascribed to the changes in the hydrogen-bonding environment around the local environment of nitriles, accurately modeled through high-level molecular dynamics simulations using the AMOEBA force field. Our findings underscore the QCL spectrometers ability to enhance sensitivity for monitoring drug-protein interactions, offering new opportunities for advanced methodologies in drug development and biochemical research.

Authors are required to submit a graphic entry for the Table of Contents (TOC) that, in conjunction with the manuscript title, should give the reader a representative idea of one of the following: A key structure, reaction, equation, concept, or theorem, etc., that is discussed in the manuscript. Consult the journals Instructions for Authors for TOC graphic specifications.



O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=143 SRC="FIGDIR/small/670201v1_ufig1.gif" ALT="Figure 1">
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]]></description>
<dc:creator>Mukherjee, S.</dc:creator>
<dc:creator>Fried, S. D. E.</dc:creator>
<dc:creator>Hong, N. Y.</dc:creator>
<dc:creator>Bagheri, N.</dc:creator>
<dc:creator>Kozuch, J.</dc:creator>
<dc:creator>Mathews, I. I.</dc:creator>
<dc:creator>Kirsh, J. M.</dc:creator>
<dc:creator>Boxer, S. G.</dc:creator>
<dc:date>2025-08-19</dc:date>
<dc:identifier>doi:10.1101/2025.08.15.670201</dc:identifier>
<dc:title><![CDATA[Covalent Drug binding in Live Cells Monitored by Mid-IR Quantum Cascade Laser Spectroscopy: Photoactive Yellow Protein as a Model System]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-08-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.18.670983v1?rss=1">
<title>
<![CDATA[
Bivalent mRNA booster encoding virus-like particles elicits potent polyclass RBD antibodies in pre-vaccinated mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.18.670983v1?rss=1</link>
<description><![CDATA[
mRNA vaccines emerged as a leading vaccine technology during the COVID-19 pandemic. However, their sustained protective efficacies were limited by relatively short-lived antibody responses and the emergence of SARS-CoV-2 variants, necessitating frequent and variant-updated boosters. We recently developed the ESCRT- and ALIX-binding region (EABR) mRNA vaccine platform, which encodes engineered immunogens that induce budding of enveloped virus-like particles (eVLPs) from the plasma membrane, thereby resulting in presentation of immunogens on cell surfaces and eVLPs. Prior studies showed that spike (S)-EABR mRNA-LNP immunizations elicited enhanced neutralizing antibody responses against ancestral and variant SARS-CoV-2 compared with conventional S mRNA-LNP in naive mice, but the effectiveness of S-EABR mRNA-LNP boosters in the context of pre-existing immunity has not been investigated. Here, we evaluated monovalent Wuhan-Hu-1 (Wu1) and bivalent (Wu1/BA.5) S-EABR mRNA-LNP boosters in mice pre-vaccinated with conventional Wu1 S mRNA-LNP. Compared to conventional S mRNA-LNP boosters, the EABR approach enhanced monovalent and bivalent mRNA-LNP booster-induced neutralizing responses against Omicron subvariants BA.1, BA.5, BQ.1.1, and XBB.1, with bivalent S-EABR mRNA-LNP consistently eliciting the highest titers. Epitope mapping of polyclonal antisera by deep mutational scanning revealed that bivalent S-EABR mRNA-LNP boosted diverse "polyclass" anti-receptor-binding domain (RBD) responses, suggesting balanced targeting of multiple RBD epitope classes. In contrast, monovalent S, bivalent S, and monovalent S-EABR mRNA-LNP boosters elicited less diverse polyclonal serum responses primarily targeting immunodominant RBD epitopes. Cryo-EM structures demonstrated that bivalent mRNA immunizations promote S heterotrimer formation, potentially enhancing bivalent S-EABR mRNA-LNP booster-induced antibody breadth and polyclass epitope targeting by activating cross-reactive B cells through intra-S crosslinking. These findings support the future design of bivalent or multivalent S-EABR mRNA-LNP boosters as a promising strategy to confer broader, and therefore potentially more durable, protection against emerging SARS-CoV-2 variants and other rapidly evolving viruses.
]]></description>
<dc:creator>Fan, C.</dc:creator>
<dc:creator>Cohen, A. A.</dc:creator>
<dc:creator>Dam, K.-M. A.</dc:creator>
<dc:creator>Rorick, A. V.</dc:creator>
<dc:creator>Priso Fils, A.-C. I.</dc:creator>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Gnanapragasam, P. N.</dc:creator>
<dc:creator>Segovia, L. N.</dc:creator>
<dc:creator>Huey-Tubman, K. E.</dc:creator>
<dc:creator>Moon, W. J.</dc:creator>
<dc:creator>Lin, P. J.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Hoffmann, M. A.</dc:creator>
<dc:date>2025-08-19</dc:date>
<dc:identifier>doi:10.1101/2025.08.18.670983</dc:identifier>
<dc:title><![CDATA[Bivalent mRNA booster encoding virus-like particles elicits potent polyclass RBD antibodies in pre-vaccinated mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-08-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.22.671877v1?rss=1">
<title>
<![CDATA[
Optimized R2 Retroelement Complexes Enable Precise and Efficient DNA Insertion into Plant Genomes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.22.671877v1?rss=1</link>
<description><![CDATA[
Precise, targeted insertion of multi-kilobase DNA sequences into plant genomes is critical for studying gene function, ensuring robust transgene expression, and stacking traits in crops, but remains challenging. Existing targeted insertion methods in plants relying on programmable nucleases are inefficient and can generate unwanted mutations. Newer technologies based on prime editors, transposases, and site-specific recombinases extend capabilities but remain constrained with low efficiencies, off-target integration, silencing, or limited DNA payload size. R2 non-long terminal repeat (non-LTR) retrotransposons integrate via target-primed reverse transcription (TPRT) specifically targeting the 25S ribosomal DNA multicopy site and enabling double-strand-break-free installation of gene-sized DNA sequences. We adapted the avian Taeniopygia guttata R2 protein (R2Tg) for targeted DNA insertion into plant genomes through engineering of R2Tg expression cassettes and RNA payloads carrying intron-disrupted mCherry and RUBY retrotransposition reporters with length-optimized rDNA homology arms. These efforts, together with optimized construct delivery formats and incubation temperatures, define R2 editor design rules enabling efficient DNA integration and functional protein expression from the 25S rDNA locus. In Nicotiana benthamiana leaves, Arabidopsis thaliana protoplasts, and Solanum lycopersicum seedlings, the optimized R2Tg editor system achieved targeted insertion with efficiencies up to 24% payloads ranging in size from 2kb to 5kb. This work establishes a compact R2Tg ribonucleoprotein platform for targeted DNA insertion into plant genomes, targeting a multicopy genomic safe harbor site to enable efficient multi-kilobase gene addition
]]></description>
<dc:creator>Muchenje, K. T.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Oz, T. M.</dc:creator>
<dc:creator>Li, E.</dc:creator>
<dc:creator>Saffron, A.</dc:creator>
<dc:creator>Demirer, G. S.</dc:creator>
<dc:date>2025-08-24</dc:date>
<dc:identifier>doi:10.1101/2025.08.22.671877</dc:identifier>
<dc:title><![CDATA[Optimized R2 Retroelement Complexes Enable Precise and Efficient DNA Insertion into Plant Genomes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-08-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.20.671385v1?rss=1">
<title>
<![CDATA[
GeneSys: Generative Modeling of Developmental System 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.20.671385v1?rss=1</link>
<description><![CDATA[
Temporal single-cell transcriptomics enables the reconstruction of dynamic gene expression changes during development. Yet, its analytical power is often limited by data sparsity, technical noise, and imbalanced representation of cell types across time points. To overcome these challenges, we present GeneSys (Generative Modeling of Developmental System), a generative deep learning model that simulates single-cell transcriptomic landscapes under developmental constraints, which is informed by prior biological knowledge or user-defined hypotheses. GeneSys integrates a temporal variational autoencoder with a cell-type classifier, requiring a lineage blueprint as input, which enables it to model the temporal transitions of transcriptional states with cell-type specificity. Leveraging data from Arabidopsis thaliana roots and mouse embryos, we show that GeneSys learns robust developmental trajectories, generates imputed and representative transcriptomes, and enhances gene prioritization accuracy compared to unregularized scRNA-seq data. By applying gene masking and augmentation, GeneSys reveals interpretable gene expression programs (GEPs) and serves as an in silico platform to test the impact of specific genes or gene sets on user-defined developmental outcomes. Additionally, GeneSys computes linear interaction matrices (LIMAs) to infer dynamic gene networks and prioritize transcription factors with spatiotemporal resolution. These features enable GeneSys to nominate key genes governing state transitions in a developmental system, supporting both mechanistic insight and hypothesis generation. Together, GeneSys provides a flexible and extensible framework to denoise single-cell data and simulate transcriptomic developmental landscape guided by known or hypothesized developmental constraints, empowering the discovery of regulatory mechanisms from high-dimensional single-cell datasets.
]]></description>
<dc:creator>Hsu, C.-W.</dc:creator>
<dc:creator>Chen, C.-Y.</dc:creator>
<dc:creator>Nolan, T. M.</dc:creator>
<dc:creator>Benfey, P. N.</dc:creator>
<dc:creator>Ohler, U.</dc:creator>
<dc:date>2025-08-25</dc:date>
<dc:identifier>doi:10.1101/2025.08.20.671385</dc:identifier>
<dc:title><![CDATA[GeneSys: Generative Modeling of Developmental System]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-08-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.22.671880v1?rss=1">
<title>
<![CDATA[
Extracellular contractile injection systems for high efficiency protein delivery to plants 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.22.671880v1?rss=1</link>
<description><![CDATA[
Efficient delivery of functional proteins into plant cells remains a major barrier in plant biotechnology. Extracellular contractile injection systems (eCISs) are phage tail-like nanomachines evolved by bacteria to interface with eukaryotic host cells and deliver protein effectors. The Photorhabdus virulence cassette (PVC), a well-characterized eCIS, naturally targets insect hosts but can be reprogrammed for protein cargo delivery in mammalian systems. Here, we adapted PVCs for targeted delivery to plants by engineering their tail fibers to recognize a natural plant immune receptor, FLAGELLIN SENSITIVE2 (FLS2). We designed a library of FLS2-binding PVC variants and demonstrated efficient loading and delivery of non-native cargoes, including a fluorescent reporter protein and the Cre recombinase. We showed that engineered PVCs can deliver these proteins to Arabidopsis thaliana protoplasts and Nicotiana benthamiana leaf cells with efficiencies up to 40%. We elucidated that the delivery efficiency is correlated with receptor surface density, demonstrating that receptor selection and expression level are key parameters for optimization. This work establishes PVCs as novel, programmable protein delivery nanoparticles for plants, capable of targeting plant membrane receptors and effectively delivering diverse functional proteins. By enabling precise, DNA-free delivery of gene editing proteins, plant-targeted PVCs provide the framework for next-generation genome engineering strategies with broad potential in agricultural nanobiotechnology.
]]></description>
<dc:creator>Legendre, M. G.</dc:creator>
<dc:creator>Heredia, C. A.</dc:creator>
<dc:creator>Colee, C. M.</dc:creator>
<dc:creator>Demirer, G. S.</dc:creator>
<dc:date>2025-08-28</dc:date>
<dc:identifier>doi:10.1101/2025.08.22.671880</dc:identifier>
<dc:title><![CDATA[Extracellular contractile injection systems for high efficiency protein delivery to plants]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-08-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.25.671920v1?rss=1">
<title>
<![CDATA[
A global map of wood density 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.25.671920v1?rss=1</link>
<description><![CDATA[
Wood density influences how quickly woody plants grow, how long they live and how much carbon they store, yet its global variation remains poorly mapped. Here we combined 109,626 wood density measurements from 16,829 species with 300,949 vegetation plots to produce a km-scale map of community-weighted wood density for every woody biome. Our model led to a prediction accuracy 32-51 % higher than previous global products, and a 1.8-3.7-fold wider wood density range (0.28-1.00 g cm-3; global mean: 0.57 g cm-3) than previously assumed. Spatial cross-validation showed low bias ({+/-}2.5 % of the mean), and uncertainties decreased from 20% in poorly sampled drylands and boreal regions to 5% in data-rich temperate forests. Mean annual temperature was the best predictor of community-weighted mean wood density, increasing by 0.01 g cm-3 for every 1{degrees}C change. We deliver a low-bias, high-resolution wood density layer for Earth system models, together with spatially explicit error maps. This study represents a major step forward for carbon accounting and trait-based forecasts of vegetation change.
]]></description>
<dc:creator>Fischer, F. J.</dc:creator>
<dc:creator>Chave, J.</dc:creator>
<dc:creator>Zanne, A.</dc:creator>
<dc:creator>Jucker, T.</dc:creator>
<dc:creator>Fajardo, A.</dc:creator>
<dc:creator>Fayolle, A.</dc:creator>
<dc:creator>de Lima, R. A. F.</dc:creator>
<dc:creator>Vieilledent, G.</dc:creator>
<dc:creator>Beeckman, H.</dc:creator>
<dc:creator>Hubau, W.</dc:creator>
<dc:creator>De Mil, T.</dc:creator>
<dc:creator>Wallenus, D.</dc:creator>
<dc:creator>Aldana, A. M.</dc:creator>
<dc:creator>Alvarez-Davila, E.</dc:creator>
<dc:creator>Alves, L. F.</dc:creator>
<dc:creator>Apgaua, D. M. G.</dc:creator>
<dc:creator>Arcanjo, F.</dc:creator>
<dc:creator>Bastin, J.-F.</dc:creator>
<dc:creator>Bilous, A.</dc:creator>
<dc:creator>Birnbaum, P.</dc:creator>
<dc:creator>Blyshchyk, V.</dc:creator>
<dc:creator>Borah, J.</dc:creator>
<dc:creator>Boukili, V.</dc:creator>
<dc:creator>Camarero, J. J.</dc:creator>
<dc:creator>Casas, L.</dc:creator>
<dc:creator>Cazzolla Gatti, R.</dc:creator>
<dc:creator>Chambers, J. Q.</dc:creator>
<dc:creator>Chimbioputo Fabiano, E.</dc:creator>
<dc:creator>Choat, B.</dc:creator>
<dc:creator>Cifuentes, E.</dc:creator>
<dc:creator>Conti, G.</dc:creator>
<dc:creator>Coomes, D.</dc:creator>
<dc:creator>Cornwell, W.</dc:creator>
<dc:creator>Dar, J. A.</dc:creator>
<dc:creator>Das, A. K.</dc:creator>
<dc:creator>Dobler, M.</dc:creator>
<dc:creator>Dougabka, D.</dc:creator>
<dc:creator>Edwards, D. P.</dc:creator>
<dc:creator>Eggli, U.</dc:creator>
<dc:creator>Evans, R.</dc:creator>
<dc:creator>Falster, D.</dc:creator>
<dc:creator>Fearnside, P.</dc:creator>
<dc:creator>Flores,</dc:creator>
<dc:date>2025-08-28</dc:date>
<dc:identifier>doi:10.1101/2025.08.25.671920</dc:identifier>
<dc:title><![CDATA[A global map of wood density]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-08-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.28.672467v1?rss=1">
<title>
<![CDATA[
Light on its feet: Acclimation to high and low diurnal light is flexible in Chlamydomonas reinhardtii 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.28.672467v1?rss=1</link>
<description><![CDATA[
Chlamydomonas acclimates to repeated low (LL) or high light (HL) days by changing the abundance of photosynthetic complexes and the ultrastructure of its thylakoid membranes. These phenotypes persist through the night phases, suggesting a readiness for the daylight environment that is routinely experienced despite the intervening dark periods (Dupuis & Ojeda et al. 2025). Here, we investigate how prior acclimation impacts algal fitness upon a change in daylight intensity and how quickly Chlamydomonas can reprogram its photoprotective strategy in a diurnal context. We performed a systems analysis of synchronized populations acclimated to diurnal LL when subjected to HL days and of populations acclimated to diurnal HL when subjected to LL days. In the latter case, diurnal photoacclimation decreased fitness during the first day at a new light intensity: HL-acclimated cells barely increased in size over the first LL period, and they failed to complete a cell cycle. However, although LL-acclimated cells showed severe photodamage after 6 hours of HL, they recovered chloroplast form and function later that afternoon and successfully divided at nightfall. These cells rapidly altered their thylakoid membrane ultrastructure, increased their photoprotective quenching capacity, and decreased their inventory of photosystem and antenna proteins by the end of the first HL day. Transcriptomic and proteomic analyses revealed rapid induction of thousands of genes, including those encoding proteases, chaperones, and other proteins involved in the chloroplast unfolded protein response. These results show that the alga is highly flexible and competent to rapidly acclimate to changes in diurnal light intensity.
]]></description>
<dc:creator>Dupuis, S.</dc:creator>
<dc:creator>Chastain, J. L.</dc:creator>
<dc:creator>Han, G.</dc:creator>
<dc:creator>Zhong, V.</dc:creator>
<dc:creator>Gallaher, S. D.</dc:creator>
<dc:creator>Nicora, C. D.</dc:creator>
<dc:creator>Purvine, S. O.</dc:creator>
<dc:creator>Lipton, M. S.</dc:creator>
<dc:creator>Niyogi, K. K.</dc:creator>
<dc:creator>Iwai, M.</dc:creator>
<dc:creator>Merchant, S. S.</dc:creator>
<dc:date>2025-09-02</dc:date>
<dc:identifier>doi:10.1101/2025.08.28.672467</dc:identifier>
<dc:title><![CDATA[Light on its feet: Acclimation to high and low diurnal light is flexible in Chlamydomonas reinhardtii]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.28.672887v1?rss=1">
<title>
<![CDATA[
Zebrafish sleep displays distinct sub-states 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.28.672887v1?rss=1</link>
<description><![CDATA[
Sleep is an essential and evolutionarily-conserved behavior. While mammals and several other species have been shown to exhibit well-defined sleep sub-states, some of which have been ascribed specific functions, it remains unclear to what extent such differentiation exists across the animal kingdom. Here we show, using long-term behavioral data combined with Hidden Markov Modeling, that larval zebrafish display distinct deep and light sleep sub-states. Although both states occur primarily at night, fish respond differently to sleep deprivation and arousing stimuli depending on which sleep sub-state they are in. Moreover, the proportions of deep and light sleep are selectively altered by genetic and pharmacological manipulations of melatonin, serotonin, and norepinephrine signaling, offering new insights into how these neuromodulators shape sleep architecture. These results support zebrafish as a tractable model for dissecting the regulation and function of sleep sub-states. More broadly, they demonstrate that structured, multi-state sleep is a conserved feature of vertebrate behavior.
]]></description>
<dc:creator>Tripathi, R.</dc:creator>
<dc:creator>Oikonomou, G.</dc:creator>
<dc:creator>Prober, D. A.</dc:creator>
<dc:creator>Goodhill, G.</dc:creator>
<dc:date>2025-09-02</dc:date>
<dc:identifier>doi:10.1101/2025.08.28.672887</dc:identifier>
<dc:title><![CDATA[Zebrafish sleep displays distinct sub-states]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.08.31.673375v1?rss=1">
<title>
<![CDATA[
The Global Canopy Atlas: analysis-ready maps of 3D structure for the world's woody ecosystems 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.08.31.673375v1?rss=1</link>
<description><![CDATA[
Woody canopies regulate exchanges of energy, water and carbon, and their three-dimensional (3D) structure supports much of terrestrial biodiversity. Remote sensing technologies such as airborne laser scanning (ALS) now enable the 3D mapping of entire landscapes. However, we lack the large, harmonized and geographically representative ALS collections needed to build a global picture of woody ecosystem structure. To address this challenge, we developed the Global Canopy Atlas (GCA): 3,458 ALS acquisitions transformed into standardized and analysis-ready maps of canopy height and elevation at 1 m2 resolution. The GCA covers 56,554 km2 across all major biomes. 19% of this area has been scanned multiple times, and 87% of all GCA products are openly available, covering 95% of the total area. To showcase its wide range of applications, we applied the GCA in three case studies. First, we validated three global satellite-derived canopy height maps, finding poor performance at native resolution (1-30 m, R2 < 0.38) and moderate performance at 250 m resolution (R2 < 0.65). Second, analyzing global patterns in canopy gap size frequency we discovered an unexpectedly large variation of power law exponents from branch to stand level ( = 1.52 to 2.38), pointing to a fundamental scale-dependence of forest structure. Third, we developed a framework to standardize forest turnover quantification from multi-source, multi-temporal ALS. In a temperate forest in North America it revealed that 21% of canopy gaps closed within 12 years of opening and would thus be missed by infrequent monitoring. As demonstrated by these case studies, the GCA provides a novel data source for ecologists, foresters, remote sensing scientists and the ecosystem modelling community that substantially advances our ability to understand the structure and dynamics of woody ecosystems at global scales.
]]></description>
<dc:creator>Fischer, F. J.</dc:creator>
<dc:creator>Morgan, B.</dc:creator>
<dc:creator>Jackson, T.</dc:creator>
<dc:creator>Chave, J.</dc:creator>
<dc:creator>Coomes, D.</dc:creator>
<dc:creator>Cushman, K.</dc:creator>
<dc:creator>Dalagnol, R.</dc:creator>
<dc:creator>Dalponte, M.</dc:creator>
<dc:creator>Duncanson, L.</dc:creator>
<dc:creator>Saatchi, S.</dc:creator>
<dc:creator>Seidl, R.</dc:creator>
<dc:creator>Sterenczak, K.</dc:creator>
<dc:creator>Laurin, G. V.</dc:creator>
<dc:creator>Adu-Bredu, S.</dc:creator>
<dc:creator>Aguirre-Gutierrez, J.</dc:creator>
<dc:creator>Antonielli, B.</dc:creator>
<dc:creator>Armston, J. D.</dc:creator>
<dc:creator>de Assis, M. L.</dc:creator>
<dc:creator>Barbier, N.</dc:creator>
<dc:creator>Burt, A.</dc:creator>
<dc:creator>Cesar, R. G.</dc:creator>
<dc:creator>Cervenka, J.</dc:creator>
<dc:creator>Coops, N.</dc:creator>
<dc:creator>Cullen, L.</dc:creator>
<dc:creator>Dalling, J. W.</dc:creator>
<dc:creator>Davies, A.</dc:creator>
<dc:creator>Demol, M.</dc:creator>
<dc:creator>Ebenbeck, J.</dc:creator>
<dc:creator>Fassnacht, F.</dc:creator>
<dc:creator>Fatoyinbo, L.</dc:creator>
<dc:creator>Garcia, M.</dc:creator>
<dc:creator>Gasparri, N. I.</dc:creator>
<dc:creator>Gobakken, T.</dc:creator>
<dc:creator>Goodbody, T. R. H.</dc:creator>
<dc:creator>Görgens, E. B.</dc:creator>
<dc:creator>Gorum, T.</dc:creator>
<dc:creator>Gosper, C.</dc:creator>
<dc:creator>Guan, H.</dc:creator>
<dc:creator>Heiskanen, J.</dc:creator>
<dc:creator>Heurich, M.</dc:creator>
<dc:creator>Hobi, M.</dc:creator>
<dc:creator>Höfle, B.</dc:creator>
<dc:creator>Hooijer, A.</dc:creator>
<dc:creator>Huth,</dc:creator>
<dc:date>2025-09-04</dc:date>
<dc:identifier>doi:10.1101/2025.08.31.673375</dc:identifier>
<dc:title><![CDATA[The Global Canopy Atlas: analysis-ready maps of 3D structure for the world's woody ecosystems]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.03.674039v1?rss=1">
<title>
<![CDATA[
Reference-based variant detection with varseek 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.03.674039v1?rss=1</link>
<description><![CDATA[
Variant detection from sequencing data is fundamental for genomics and is the first step in a wide range of applications, ranging from genome-wide association studies to disease diagnosis. Widely used tools for variant detection utilize a de novo approach that is based on a combination of read mapping algorithms and statistical methods for identifying genetic variation from error-prone sequencing data. This approach has been successful, although the detection of insertion and deletion variants, as well as the detection of variants from low-coverage data, remain challenging problems. We introduce varseek, a reference-based approach to variant detection that provides large improvements in performance in these challenging cases. The varseek approach utilizes a k-mer pseudoalignment approach, which provides the ability to identify variants at single-cell resolution in single-cell transcriptomics data. We showcase the versatility and performance of varseek for detecting tumor-specific COSMIC variants in glioblastoma single-cell sequencing.
]]></description>
<dc:creator>Rich, J. M.</dc:creator>
<dc:creator>Luebbert, L.</dc:creator>
<dc:creator>Sullivan, D. K.</dc:creator>
<dc:creator>Rosa, R.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2025-09-05</dc:date>
<dc:identifier>doi:10.1101/2025.09.03.674039</dc:identifier>
<dc:title><![CDATA[Reference-based variant detection with varseek]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.05.674437v1?rss=1">
<title>
<![CDATA[
Identification of a broad and potent V3 glycan site bNAb targeting anN332gp120 glycan-independent epitope 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.05.674437v1?rss=1</link>
<description><![CDATA[
Broadly neutralizing antibodies (bNAbs) against HIV-1 can suppress viremia in vivo and inform vaccine development. Here, we characterized 007, a V3 glycan site bNAb exhibiting high levels of antiviral activity against multiclade pseudovirus panels1-3 (GeoMean IC50 = 0.012 {micro}g/mL, breadth = 69%, 217 virus strains) by targeting a N332gp120 glycan-independent V3 epitope, a site of Env vulnerability to which only weakly neutralizing antibodies had previously been identified. Functional analyses demonstrated distinct binding and neutralization profiles compared to classical V3 glycan site bNAbs. A 007 Fab-Env cryo-EM structure revealed contacts with the V3 324GD/NIR327 motif and interactions with N156gp120 and N301gp120 glycans. In contrast to classical V3 bNAbs, 007 binding to Env does not depend on the N332gp120 glycan, rendering it resistant to common escape mutations. Structures of 007 IgG-Env trimer complexes showed two Env trimers crosslinked by three bivalent IgGs, and bivalent 007 IgG was up to [~]300-fold more potent than monovalent 007 IgG heterodimer, suggesting a role for avidity in potent neutralization. Finally, in HIV-1ADA-infected humanized mice, 007 caused transient decline of viremia and overcame classical V3 escape mutations, highlighting 007s potential for HIV-1 prevention, therapy, functional cure, and vaccine design.
]]></description>
<dc:creator>Gieselmann, L.</dc:creator>
<dc:creator>DeLaitsch, A. T.</dc:creator>
<dc:creator>Rohde, M.</dc:creator>
<dc:creator>Radford, C.</dc:creator>
<dc:creator>Worczinski, J.</dc:creator>
<dc:creator>Momot, A.</dc:creator>
<dc:creator>Ahmadov, E.</dc:creator>
<dc:creator>Burger, J. A.</dc:creator>
<dc:creator>Havenar-Daughton, C.</dc:creator>
<dc:creator>Deshpande, S.</dc:creator>
<dc:creator>Giovannoni, F.</dc:creator>
<dc:creator>Corti, D.</dc:creator>
<dc:creator>Kreer, C.</dc:creator>
<dc:creator>Ercanoglu, M. S.</dc:creator>
<dc:creator>Schommers, P.</dc:creator>
<dc:creator>Georgiev, I.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Knuefer, J.</dc:creator>
<dc:creator>Stumpf, R.</dc:creator>
<dc:creator>Kroidl, A.</dc:creator>
<dc:creator>Geldmacher, C.</dc:creator>
<dc:creator>Maganga, L.</dc:creator>
<dc:creator>William, W.</dc:creator>
<dc:creator>Ntinginya, N. E.</dc:creator>
<dc:creator>Hoelscher, M.</dc:creator>
<dc:creator>Yang, Z.</dc:creator>
<dc:creator>Wei, Q.</dc:creator>
<dc:creator>Renfrow, M.</dc:creator>
<dc:creator>Green, T. J.</dc:creator>
<dc:creator>Novak, J.</dc:creator>
<dc:creator>van Gils, M.</dc:creator>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>Gruell, H.</dc:creator>
<dc:creator>Bloom, J. D.</dc:creator>
<dc:creator>Seaman, M. S.</dc:creator>
<dc:creator>Bjorkman, P.</dc:creator>
<dc:creator>Klein, F.</dc:creator>
<dc:date>2025-09-10</dc:date>
<dc:identifier>doi:10.1101/2025.09.05.674437</dc:identifier>
<dc:title><![CDATA[Identification of a broad and potent V3 glycan site bNAb targeting anN332gp120 glycan-independent epitope]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.09.675098v1?rss=1">
<title>
<![CDATA[
stk32a links sleep homeostasis to suppression of sensory and motor systems 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.09.675098v1?rss=1</link>
<description><![CDATA[
Sleep is regulated by a homeostatic process and associated with an increased arousal threshold, but the genetic and neuronal mechanisms that implement these essential features of sleep remain poorly understood. To address these fundamental questions, we performed a zebrafish genetic screen informed by human genome-wide association studies. We found that mutation of serine/threonine kinase 32a (stk32a) results in increased sleep and impaired sleep homeostasis in both zebrafish and mice, and that stk32a acts downstream of neurotensin signaling and the serotonergic raphe in zebrafish. stk32a mutation reduces phosphorylation of neurofilament proteins, which are co-expressed with stk32a in neurons that regulate motor activity and in lateral line hair cells that detect environmental stimuli, and ablating these cells phenocopies stk32a mutation. Neurotensin signaling inhibits specific sensory and motor populations, and blocks stimulus-evoked responses of neurons that relay sensory information from hair cells to the brain. Our work thus shows that stk32a is an evolutionarily conserved sleep regulator that links neuropeptidergic and neuromodulatory systems to homeostatic sleep drive and changes in arousal threshold, which are implemented through suppression of specific sensory and motor systems.
]]></description>
<dc:creator>Tran, S.</dc:creator>
<dc:creator>Emtage, J.</dc:creator>
<dc:creator>Zhang, C.</dc:creator>
<dc:creator>Liu, X.</dc:creator>
<dc:creator>Lecoeuche, M.</dc:creator>
<dc:creator>Andreev, A.</dc:creator>
<dc:creator>Oikonomou, G.</dc:creator>
<dc:creator>Narayan, S.</dc:creator>
<dc:creator>Garcia, B.</dc:creator>
<dc:creator>Cammidge, T.</dc:creator>
<dc:creator>Gonzales, C.</dc:creator>
<dc:creator>Hurley, H.</dc:creator>
<dc:creator>Yap, M.</dc:creator>
<dc:creator>Li, S.</dc:creator>
<dc:creator>Wang, F.</dc:creator>
<dc:creator>Wang, T.-Y.</dc:creator>
<dc:creator>Ahrens, M. B.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Xu, M.</dc:creator>
<dc:creator>Liu, Q.</dc:creator>
<dc:creator>Prober, D. A.</dc:creator>
<dc:date>2025-09-11</dc:date>
<dc:identifier>doi:10.1101/2025.09.09.675098</dc:identifier>
<dc:title><![CDATA[stk32a links sleep homeostasis to suppression of sensory and motor systems]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.09.675218v1?rss=1">
<title>
<![CDATA[
Next-generation hybridization chain reaction tools with enhanced sensitivities to detect challenging targets 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.09.675218v1?rss=1</link>
<description><![CDATA[
Compared to traditional enzyme-based in situ amplification methods, Hybridization Chain Reaction v3.0 (HCR v3.0) offers high specificity for spatial RNA visualization but lacks the sensitivity needed for short or low-abundance targets, especially in thick tissue with high autofluorescence. We describe next-generation HCR detection methods that combine the specificity of HCR v3.0 with enzyme-based signal amplification through catalysis (HCR-Cat) or immunostaining (HCR-Immuno, HCR-Multi). These methods enhance sensitivity for robust spatial detection of both short and low-abundance targets, work well in challenging tissue environments, and enable broad utility across basic research and translational applications. These methods allow spatial detection of challenging targets that are poorly-accessible using HCR v3.0, as well as quantitative analysis of single transcripts even when targeting short RNAs with a limited number of probes.
]]></description>
<dc:creator>Singh, C.</dc:creator>
<dc:creator>Bali, N.</dc:creator>
<dc:creator>Coughlin, G. M.</dc:creator>
<dc:creator>Xu, J.</dc:creator>
<dc:creator>Polansky, J. Y.</dc:creator>
<dc:creator>Herget, U.</dc:creator>
<dc:creator>Gilbert, M. S.</dc:creator>
<dc:creator>Cammidge, T.</dc:creator>
<dc:creator>Spigolon, G.</dc:creator>
<dc:creator>Smirnova, Y.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:creator>Zinn, K.</dc:creator>
<dc:creator>Prober, D. A.</dc:creator>
<dc:date>2025-09-11</dc:date>
<dc:identifier>doi:10.1101/2025.09.09.675218</dc:identifier>
<dc:title><![CDATA[Next-generation hybridization chain reaction tools with enhanced sensitivities to detect challenging targets]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.09.675233v1?rss=1">
<title>
<![CDATA[
Pth4 neurons define a novel hypothalamic circuit that promotes sleep via brainstem monoaminergic neurons 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.09.675233v1?rss=1</link>
<description><![CDATA[
Classical studies identified a critical role for the hypothalamus in regulating sleep and wake states, but few such hypothalamic neuronal populations have been identified. Here we describe a sleep-promoting population of hypothalamic neurons that expresses the neuropeptides QRFP and parathyroid hormone 4 (Pth4) in zebrafish. Optogenetic stimulation of these neurons results in a large increase in sleep that requires pth4 but not qrfp. Noradrenergic locus coeruleus (LC) neurons and serotonergic raphe neurons (RN) in the hindbrain express distinct pth receptors, and genetic epistasis and cell ablation experiments revealed that Pth4 neuron-induced sleep is suppressed in mutants that lack noradrenaline in the LC or lack the serotonergic RN. Pth4 neuron-induced sleep is also suppressed in serine/threonine kinase 32a (stk32a) mutants, possibly via stk32a-expressing neurons in the prethalamus that express pth receptors. These results identify QRFP/Pth4 neurons as a novel hypothalamic sleep-promoting population and support a model in which distinct sleep- and wake-promoting hypothalamic populations act via monoaminergic neurons in the hindbrain to control vigilance state.
]]></description>
<dc:creator>Herget, U.</dc:creator>
<dc:creator>Tran, S.</dc:creator>
<dc:creator>Singh, C.</dc:creator>
<dc:creator>Oikonomou, G.</dc:creator>
<dc:creator>Ryu, S.</dc:creator>
<dc:creator>Rotllant, J.</dc:creator>
<dc:creator>Prober, D. A.</dc:creator>
<dc:date>2025-09-11</dc:date>
<dc:identifier>doi:10.1101/2025.09.09.675233</dc:identifier>
<dc:title><![CDATA[Pth4 neurons define a novel hypothalamic circuit that promotes sleep via brainstem monoaminergic neurons]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.07.674745v1?rss=1">
<title>
<![CDATA[
Proliferation to suppress neoplasia: a general model and a first test in the moon jelly 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.07.674745v1?rss=1</link>
<description><![CDATA[
Cell proliferation is necessary to maintain tissue homeostasis, but proliferation carries with it a risk of cancer. Nevertheless, nature abounds with examples of organisms that achieve low rates of cancer while also proliferating to maintain tissue homeostasis. To understand how organisms might achieve both of these goals, we developed a dynamical model describing cell birth, death, and mutation in a population. The model identifies two distinct regimes. In one regime, as expected, decreasing proliferation delays accumulation of neoplastic cells. In another regime, unexpectedly, increasing proliferation suppresses accumulation of neoplastic cells. In this regime, when more cells proliferate, more cells correspondingly die as a consequence of homeostatic feedback. As long as neoplastic cells are detected and killed preferentially, the high flux of cells acts as a proofreader, eliminating neoplastic cells. High-flux proofreading may seem costly, but it can be effective even when the system does not have a precise detector of neoplastic cells. As a first experimental test of whether high-flux proofreading is biologically relevant, we examined the moon jelly, a cnidarian. Neoplasms have rarely been observed in cnidarians, and yet simply inhibiting proliferation is sufficient to promote neoplasms in the moon jelly. Together, the model and experiments show that high-flux proofreading is an effective cancer resistance strategy. Because cell birth, death, and mutation are fundamentally conserved processes, high-flux proofreading may be widespread. The quantitative framework presented in this study offers clear experimentally testable predictions to assess high-flux proofreading in other systems, and its potential utility for cancer prevention and treatment.
]]></description>
<dc:creator>Sarma, A. A.</dc:creator>
<dc:creator>Goentoro, L.</dc:creator>
<dc:creator>Doyle, J. C.</dc:creator>
<dc:date>2025-09-12</dc:date>
<dc:identifier>doi:10.1101/2025.09.07.674745</dc:identifier>
<dc:title><![CDATA[Proliferation to suppress neoplasia: a general model and a first test in the moon jelly]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.08.674882v1?rss=1">
<title>
<![CDATA[
Soil texture regulates bacterial motility and chemotactic recruitment to plant roots 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.08.674882v1?rss=1</link>
<description><![CDATA[
Soil microbial communities regulate critical ecological processes, including nutrient cycling, carbon sequestration, and plant growth. However, due to the opacity and structural complexity of soil, how physical constraints imposed by pore geometry in-fluence bacterial motility and chemotactic recruitment to plant roots remains poorly understood. We use a transparent soil mimic composed of cryolite grains that replicate the structural characteristics of natural soils while enabling direct visualization of bacterial dynamics. Using Escherichia coli as a model bacterium, we combine macroscopic spreading assays with microscopic tracking of cellular trajectories to characterize how soil texture affects motility across pore scales. We find that bacterial motility shifts from run-and-tumble behavior in large, open pores to frequent trapping in smaller, more confined spaces. This transition is governed by the pore size distribution and leads to reduced effective diffusivity and slower population-scale spreading. Moreover, pore-scale confinement hinders the chemotactic recruitment of bacteria to Arabidopsis thaliana roots: recruitment is robust in sandy and loamy soils but negligible in highly confining textures. Our results establish soil texture as a critical factor regulating microbial dynamics and ecological interactions in the rhizosphere. This mechanistic understanding complements genomic surveys by identifying physical confinement as an ecological filter that shapes root-associated microbiomes. These findings highlight the essential and previously underappreciated role of soil texture, suggesting new strategies for managing microbial communities to promote plant health and sustainable agriculture.
]]></description>
<dc:creator>Al Harraq, A.</dc:creator>
<dc:creator>Choi, G.</dc:creator>
<dc:creator>Datta, S. S.</dc:creator>
<dc:creator>Shaevitz, J. W.</dc:creator>
<dc:date>2025-09-12</dc:date>
<dc:identifier>doi:10.1101/2025.09.08.674882</dc:identifier>
<dc:title><![CDATA[Soil texture regulates bacterial motility and chemotactic recruitment to plant roots]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.12.675751v1?rss=1">
<title>
<![CDATA[
Leveraging bioorthogonal conjugation for alpha synuclein fibril surveillance 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.12.675751v1?rss=1</link>
<description><![CDATA[
Alpha synuclein (-syn) amyloid fibrils are associated with various neurodegenerative diseases. To better understand the molecular and cellular basis for -syn fibril persistence and spread, we implemented a fluorophore labeling strategy to surveil pre-formed -syn fibrils in solution and in cells. We leveraged amber codon mediated incorporation of a tetrazine-based artificial amino acid (TetV2.0) to install a cyclooctene-conjugated Janeliaflour, JF549, at four sites on human -syn: residues 4, 60, 96 and 136. Fast coupling occurred under mild buffer conditions and in the presence of the disease-associated cofactor and cytotoxic lipid, psychosine. Labeled fibrils retained their polymorphic features, seeded the growth of new fibrils in vitro, and induced the seeding of positive puncta in -syn FRET biosensor HEK293T cells. This allowed simultaneous tracking of exogenous and endogenous -syn aggregates in biosensor cells, and their localization within the cells. In doing so, our approach facilitates more detailed mechanistic investigation of -syn aggregates.
]]></description>
<dc:creator>Jenkins, R. A.</dc:creator>
<dc:creator>Wu, S.</dc:creator>
<dc:creator>Fujimura, G.</dc:creator>
<dc:creator>Heredia, A.</dc:creator>
<dc:creator>Flowers, C.</dc:creator>
<dc:creator>Sun, C.</dc:creator>
<dc:creator>Sawaya, M.</dc:creator>
<dc:creator>Loo, J.</dc:creator>
<dc:creator>Rodriguez, J. A.</dc:creator>
<dc:date>2025-09-17</dc:date>
<dc:identifier>doi:10.1101/2025.09.12.675751</dc:identifier>
<dc:title><![CDATA[Leveraging bioorthogonal conjugation for alpha synuclein fibril surveillance]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.12.675966v1?rss=1">
<title>
<![CDATA[
A male-derived volatile sex pheromone in <Caenorhabditis> nematodes identified through its mimicry by a predator 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.12.675966v1?rss=1</link>
<description><![CDATA[
Recent studies demonstrated that the predacious fungi Arthrobotrys oligospora emits a mixture of volatile chemical cues that function to attract nematode prey. The strong attraction elicited by one of the mixture components, methyl 3-methyl-2-butenoate (MMB), was highly female- and hermaphrodite-specific within several Caenorhabditis species, including C. remanei and C. elegans, suggesting that MMB might function as a mimic of an endogenous, male-produced, volatile sex pheromone (VSP) within these species. Here, we report evidence that MMB is produced by C. remanei males at levels that are attractive to C. remanei females and C. elegans hermaphrodites. Notably, MMB production was not detected for C. elegans males; a finding which correlates with behavioral assays for which worm-conditioned media (WCM) prepared from C. remanei, but not from C. elegans adult males is strongly attractive to both C. remanei females and C. elegans hermaphrodites. Our findings establish MMB as the first chemically identified VSP in nematodes and show that A. oligospora exploits a dual strategy of chemical deception--mimicry and eavesdropping--to enhance prey capture.
]]></description>
<dc:creator>Gronquist, M. R.</dc:creator>
<dc:creator>Wan, X.</dc:creator>
<dc:creator>Leighton, D.</dc:creator>
<dc:creator>Togawa, Y.</dc:creator>
<dc:creator>Sagawa, M.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Schroeder, F. C.</dc:creator>
<dc:creator>Shinya, R.</dc:creator>
<dc:date>2025-09-17</dc:date>
<dc:identifier>doi:10.1101/2025.09.12.675966</dc:identifier>
<dc:title><![CDATA[A male-derived volatile sex pheromone in <Caenorhabditis> nematodes identified through its mimicry by a predator]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.17.676900v1?rss=1">
<title>
<![CDATA[
Influence of heterotrophs on phage infection of marine picocyanobacteria 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.17.676900v1?rss=1</link>
<description><![CDATA[
Picocyanobacteria Prochlorococcus and Synechococcus coexist with both their lytic phages and heterotrophic bacteria in the oceans. These lytic phages are a significant cause of mortality, and heterotrophic bacteria have been shown to increase the fitness of Prochlorococcus by reducing oxidative stress and cross feeding under extended darkness. Studies of Prochlorococcus-phage interactions are often done with xenic cultures as it has been historically difficult to obtain and maintain heterotroph-free cultures. Here we examine the effects of heterotrophic bacteria on phage infection in Prochlorococcus and Synechococcus by comparing phage infection dynamics in cultures with and without heterotrophs present. We found that Prochlorococcus populations resumed growth following infection only in the presence of heterotrophs, independent of phage:host or heterotroph:host ratios. In phage:host pairing with Synechococcus the outcomes varied, suggesting that the impact of heterotrophs on phage infection may be dependent on the phage:host interaction. In cases where the host recovered from phage infection, heterotrophs appeared to facilitate it both by mitigating oxidative stress and possibly supplying organic carbon sources, which may support post-infection growth. Furthermore, Prochlorococcus and Synechococcus populations that recovered from infection were resistant to phage infection when transferred to fresh media. Evidence argues against genetic change as the mechanism of resistance, suggesting that Prochlorococcus and Synechococcus populations in co-culture with heterotrophs undergo non-genetic adaptations during recovery from phage infection, likely driven by heterotroph-derived organic compounds that reshape host metabolism and confer protection against future lysis.
]]></description>
<dc:creator>Coe, A.</dc:creator>
<dc:creator>Parker, S. M.</dc:creator>
<dc:creator>Vo, N. N.</dc:creator>
<dc:creator>Kearney, S. M.</dc:creator>
<dc:creator>Pollak, S.</dc:creator>
<dc:creator>von Emster, K.</dc:creator>
<dc:creator>Mullet, J. I.</dc:creator>
<dc:creator>Castro, K. G.</dc:creator>
<dc:creator>Chisholm, S. W.</dc:creator>
<dc:date>2025-09-18</dc:date>
<dc:identifier>doi:10.1101/2025.09.17.676900</dc:identifier>
<dc:title><![CDATA[Influence of heterotrophs on phage infection of marine picocyanobacteria]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.18.677064v1?rss=1">
<title>
<![CDATA[
Phage-mediated lysis increases growth rate of surviving bacterial cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.18.677064v1?rss=1</link>
<description><![CDATA[
Bacterial phage infection and subsequent lysis are traditionally considered mechanisms of bacterial mortality and viral propagation; additionally, emerging evidence indicates that they may also contribute to nutrient recycling in broader ecological systems. However, it remains unclear how the nutrients released during cell lysis affect the growth dynamics of the remaining bacterial population. Addressing this gap, we built a controlled system consisting of two Escherichia coli lysogenic strains: one carrying a wild-type{lambda} prophage and the other a temperature-inducible variant that can be induced to lyse at 38 {degrees}C. Using this system, we selectively induced phage lysis in a defined fraction of the population and quantified both total biomass and the biomass of surviving, non-lysed cells. We observed that the biomass loss was consistently smaller than expected based on the fraction of lysed cells, supporting the idea that some of the released biomass is rapidly recycled by the non-lysed population. To formalize the observed dynamics and obtain quantitative insight, we developed a mathematical model showing that nutrients released during lysis can transiently enhance the growth rate of the surviving, non-lysed cells. This effect emerges on a short timescale of minutes, consistent with the rapid onset of biomass compensation observed experimentally. The growth rate increase was confirmed in single-cell experiments using microfluidics and time-lapse microscopy, where we cultured wild-type lysogens in lysate-containing culture supernatants. In summary, the results suggest that nutrients released through lysis are rapidly consumed, leading to an acceleration in the growth rate of non-lysed cells. The consequent partial compensation for cell loss can substantially influence the population dynamics, highlighting phage lysis as a direct modulator of bacterial growth. Overall, our findings provide quantitative insights into how phage-mediated lysis affects the physiology of non-lysed bacterial cells, extending beyond its well-established role in biomass recycling.
]]></description>
<dc:creator>Fara, E.</dc:creator>
<dc:creator>Raach, B.</dc:creator>
<dc:creator>Cavallaro, A.</dc:creator>
<dc:creator>Fink, J. W.</dc:creator>
<dc:creator>Ramesh, D.</dc:creator>
<dc:creator>Guo, Y.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:creator>Hall, A. R.</dc:creator>
<dc:creator>Micali, G.</dc:creator>
<dc:creator>Ackermann, M.</dc:creator>
<dc:creator>Schubert, O. T.</dc:creator>
<dc:date>2025-09-18</dc:date>
<dc:identifier>doi:10.1101/2025.09.18.677064</dc:identifier>
<dc:title><![CDATA[Phage-mediated lysis increases growth rate of surviving bacterial cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.18.677115v1?rss=1">
<title>
<![CDATA[
Extracellular matrix chemistry tunes bacterial biofilm metabolism and optimizes fitness 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.18.677115v1?rss=1</link>
<description><![CDATA[
Chemically complex extracellular matrices define cellular microenvironments and shape cell behavior. We hypothesized a composition-properties-function relationship in these natural living materials, where interactions among matrix components govern material properties and cellular physiology. Using Pseudomonas aeruginosa biofilms as a model system, we show that electrostatic interactions between the cationic polysaccharide Pel and extracellular DNA (eDNA) regulate retention of pyocyanin (PYO), a redox-active metabolite that supports anaerobic metabolism via extracellular electron transfer (EET). Biofilm-mimetic hydrogels and natural biofilms revealed that altering Pels charge via pH adjustment or chemical acetylation, or tuning the Pel:eDNA ratio, predictably modulates PYO retention and EET efficiency. Functionally, a lower Pel:eDNA ratio enhances metabolism under oxygen limitation, whereas a higher ratio promotes survival under antibiotic stress. These findings highlight how matrix chemistry encodes tunable material properties that confer biofilm fitness advantages and establish a materials-based framework for understanding extracellular matrices in multicellular communities.
]]></description>
<dc:creator>Li, J.</dc:creator>
<dc:creator>Squyres, G. R.</dc:creator>
<dc:creator>Duong, K.</dc:creator>
<dc:creator>Reichhardt, C.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:creator>Parsek, M. R.</dc:creator>
<dc:date>2025-09-18</dc:date>
<dc:identifier>doi:10.1101/2025.09.18.677115</dc:identifier>
<dc:title><![CDATA[Extracellular matrix chemistry tunes bacterial biofilm metabolism and optimizes fitness]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.17.676398v1?rss=1">
<title>
<![CDATA[
Model-based and model-free valuation signals in the human brain vary markedly in their relationship to individual differences in behavioral control 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.17.676398v1?rss=1</link>
<description><![CDATA[
Human action selection under reinforcement is thought to rely on two distinct strategies: model-free and model-based reinforcement learning. While behavior in sequential decision-making tasks often reflects a mixture of both, the neural basis of individual differences in their expression remains unclear. To investigate this, we conducted a large-scale fMRI study with 179 participants performing a variant of the two-step task. Using both cluster-defined subgroups and computational parameter estimates, we found that the ventromedial prefrontal cortex encodes model-based and model-free value signals differently depending on individual strategy use. Model-based value signals were strongly linked to the degree of model-based behavioral reliance, whereas model-free signals appeared regardless of model-free behavioral influence. Leveraging the large sample, we found individuals lacking both model-based behavior and model-based neural signals exhibited impaired state prediction errors, suggesting a difficulty in building or updating their internal model of the environment. These findings indicate that model-free signals are ubiquitous across individuals, even in those not behaviorally relying on model-free strategies, while model-based representations appear only in those individuals utilizing such a strategy at the behavioral level, the absence of which may depend in part on underlying difficulties in forming accurate model-based predictions.
]]></description>
<dc:creator>Ding, W.</dc:creator>
<dc:creator>Cockburn, J.</dc:creator>
<dc:creator>Simon, J. P.</dc:creator>
<dc:creator>Johri, A.</dc:creator>
<dc:creator>Cho, S. J.</dc:creator>
<dc:creator>Oh, S.</dc:creator>
<dc:creator>Feusner, J. D.</dc:creator>
<dc:creator>Tadayonnejad, R.</dc:creator>
<dc:creator>O'Doherty, J. P.</dc:creator>
<dc:date>2025-09-19</dc:date>
<dc:identifier>doi:10.1101/2025.09.17.676398</dc:identifier>
<dc:title><![CDATA[Model-based and model-free valuation signals in the human brain vary markedly in their relationship to individual differences in behavioral control]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.18.677192v1?rss=1">
<title>
<![CDATA[
Faecalibacterium prausnitzii, depleted in the Parkinson's disease microbiome, improves motor deficits in α-synuclein overexpressing mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.18.677192v1?rss=1</link>
<description><![CDATA[
Gut microbiome composition is altered in Parkinsons disease (PD), a neurodegenerative disorder characterized by motor dysfunction and frequently accompanied by gastrointestinal (GI) symptoms. Notably, microbial taxa with anti-inflammatory properties are consistently depleted in PD patients compared to controls. To explore whether specific gut bacteria may be disease-protective, we assembled a microbial consortium of 8 human-associated taxa that are reduced in individuals with PD across multiple cohorts and geographies. Treatment of -synuclein overexpressing (Thy1-ASO) mice, an animal model of PD, with this consortium improved motor and GI deficits. A single bacterial species from this consortium, Faecalibacterium prausnitzii, was sufficient to correct gut microbiome deviations in Thy1-ASO mice, induce anti-inflammatory immune responses, and promote protective colonic gene expression profiles. Accordingly, oral treatment with F. prausnitzii robustly ameliorated motor and GI symptoms and reduced -synuclein aggregates in the brain. These findings support the emerging hypothesis of functional contributions by the microbiome to PD and embolden development of potential probiotic therapies.
]]></description>
<dc:creator>Moiseyenko, A.</dc:creator>
<dc:creator>Antonello, G.</dc:creator>
<dc:creator>Schonhoff, A. M.</dc:creator>
<dc:creator>Boktor, J. C.</dc:creator>
<dc:creator>Long, K.</dc:creator>
<dc:creator>Dirks, B.</dc:creator>
<dc:creator>Oguienko, A. D.</dc:creator>
<dc:creator>Winnett, A. V.</dc:creator>
<dc:creator>Simpson, P.</dc:creator>
<dc:creator>Daeizadeh, D.</dc:creator>
<dc:creator>Ismagilov, R. F.</dc:creator>
<dc:creator>Krajmalnik-Brown, R.</dc:creator>
<dc:creator>Segata, N.</dc:creator>
<dc:creator>Waldron, L. D.</dc:creator>
<dc:creator>Mazmanian, S. K.</dc:creator>
<dc:date>2025-09-21</dc:date>
<dc:identifier>doi:10.1101/2025.09.18.677192</dc:identifier>
<dc:title><![CDATA[Faecalibacterium prausnitzii, depleted in the Parkinson's disease microbiome, improves motor deficits in α-synuclein overexpressing mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.19.677433v1?rss=1">
<title>
<![CDATA[
Cyclohexyl acetate functions like a volatile sex pheromone mimic in Caenorhabditis nematodes 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.19.677433v1?rss=1</link>
<description><![CDATA[
Nematodes communicate via diverse sex pheromones, including long-range volatile signals, short-range chemical cues, and contact-dependent molecules. While the ascaroside family of small molecules that mediate short-range attraction is well characterized, the identities and roles of volatile sex pheromones (VSPs) that act over longer ranges remain unknown. Using GC-MS analysis of crude VSP extracts, we identified cyclohexyl acetate (CA) as a candidate mimic, sharing retention time and mass spectral features with natural VSPs. Behavioral assays demonstrated that CA acts as a concentration-dependent, male-specific attractant in Caenorhabditis. Pre-exposure to VSPs induced cross-adaptation to CA, suggesting shared sensory processing. Surprisingly, genetic and calcium imaging analyses revealed that CA perception is mediated primarily by AWCon (str-2-expressing) neurons and involves VSPs chemoreceptor srd-1-independent pathways, which are distinct from the neural pathways involved in natural VSPs perception. These findings establish that CA is not a major component of VSPs but a structural and functional mimic of nematode VSPs, operating through a parallel sensory circuit. Although the endogenous source of CA remains unknown, its structural and behavioral mimicry provides new insights into the complexity of chemosensory signaling and the potential for interspecies chemical eavesdropping in nematode ecology.
]]></description>
<dc:creator>Wan, X.</dc:creator>
<dc:creator>Togawa, Y.</dc:creator>
<dc:creator>Gronquist, M. R.</dc:creator>
<dc:creator>Sagawa, M.</dc:creator>
<dc:creator>Leighton, D.</dc:creator>
<dc:creator>Chan, C. M.</dc:creator>
<dc:creator>Schroeder, F. C.</dc:creator>
<dc:creator>Chow, K. L.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Shinya, R.</dc:creator>
<dc:date>2025-09-21</dc:date>
<dc:identifier>doi:10.1101/2025.09.19.677433</dc:identifier>
<dc:title><![CDATA[Cyclohexyl acetate functions like a volatile sex pheromone mimic in Caenorhabditis nematodes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.20.677552v1?rss=1">
<title>
<![CDATA[
Designing signaling environments to modulate neural progenitor cell differentiation with regulatory network models 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.20.677552v1?rss=1</link>
<description><![CDATA[
During development, progenitors integrate external signaling cues to control differentiation. How combinatorial signal inputs modulate fate decisions and the underlying molecular information processing logic remains elusive. In this study, using single-cell mRNA-seq and regulatory network reconstruction, we identify an additive signal integration rule in mouse neural progenitor cells (NPCs) where the probability of neuronal versus glial cell fate choice is quantitatively regulated log-linearly by the input of EGF/FGF2, BMP4, and Wnt signaling. By profiling the developing mouse brain and NPCs cultured in different media and 40 combinatorial signaling conditions, we show that NPCs extracted from mouse embryos lost neurogenic potential during cell culture and collapsed into glial states, and that combinatorial signal inputs can restore the neuronal population following a simple log-linear model. We build regulatory network models by D-SPIN that quantitatively capture cell state distribution shifts induced by signal combinations and identify circuit structures and candidate regulators underlying the neuronal-glial fate switch, such as Olig1, Neurod1, and Hes1. Circuit models suggest that the log linearity emerges through high transcriptional heterogeneity. The models further predict an early bipotent state expressing regulators of both fates together, and we verify the bipotent state in single-cell profiling. Our work demonstrates that single-cell profiling combined with D-SPIN network reconstruction can elucidate regulatory nodes that control cell fate selection to facilitate building mechanistic models, and identifies a design principle of noise-driven additive regulation in the logarithm cell-fate probability space, providing a new strategy for population-level stem cell control.
]]></description>
<dc:creator>Jiang, J.</dc:creator>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Park, J. H.</dc:creator>
<dc:creator>Tsou, T.</dc:creator>
<dc:creator>Yang, V.</dc:creator>
<dc:creator>Rivaud, P.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2025-09-21</dc:date>
<dc:identifier>doi:10.1101/2025.09.20.677552</dc:identifier>
<dc:title><![CDATA[Designing signaling environments to modulate neural progenitor cell differentiation with regulatory network models]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.21.677609v1?rss=1">
<title>
<![CDATA[
Carbon monoxide oxidation expands the known metabolic capacity in anaerobic methanotrophic consortia 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.21.677609v1?rss=1</link>
<description><![CDATA[
Efficient energy metabolism is essential for microorganisms living on the thermodynamic edge. Consortia of anaerobic methane-oxidizing archaea (ANME-2) and sulphate-reducing bacteria (SRB) represent globally relevant syntrophic associations capable of growing with minimal amounts of free energy and can persist when methane becomes limiting. Their potential for physiological plasticity, including the use of electron donors beyond methane is poorly understood. Carbon monoxide (CO) has been reported in seep environments and represents a thermodynamically favourable alternative electron donor due to its low reduction potential. We demonstrate that environmental ANME-SRB consortia can oxidize CO in the absence of methane, in anoxic microcosm experiments using a combination of stable isotope geochemical tracers, metatranscriptomics, and single cell activity measurements (FISH-nanoSIMS). The oxidation of CO was coupled with sulphate-reduction by syntrophic consortia, and, in the absence of sulphate, through CO2 reduction to methane by ANME-2. Under these conditions, the production of methane was one ninth the rate of methanotrophy coupled to sulphate-reduction. Paired single cell FISH-nanoSIMS analysis of anabolic activity indicates that CO respiration appears to support cell maintenance rather than active growth, consistent with the observed down-regulation of energy generating complexes in ANME (e.g., mtr, rnf, etc.). The versatile capability of CO oxidation by anaerobic methanotrophic consortia broadens our understanding of carbon cycling in methane seeps and highlights potential mechanisms of resilience by methanotrophic archaea under changing geochemical regimes.
]]></description>
<dc:creator>Guo, Y.</dc:creator>
<dc:creator>Utter, D. R.</dc:creator>
<dc:creator>Murali, R.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2025-09-21</dc:date>
<dc:identifier>doi:10.1101/2025.09.21.677609</dc:identifier>
<dc:title><![CDATA[Carbon monoxide oxidation expands the known metabolic capacity in anaerobic methanotrophic consortia]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.24.678175v1?rss=1">
<title>
<![CDATA[
Lzp Ablation Ameliorates Dyslipidemia and Suppresses Atherosclerosis by Reducing Circulating Apolipoprotein B-Containing Lipoproteins 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.24.678175v1?rss=1</link>
<description><![CDATA[
As the principal regulator of systemic lipid homeostasis, the liver uniquely orchestrates dietary lipid assimilation, de novo lipogenesis, very-low-density lipoprotein (VLDL) assembly and secretion, and clearance of atherogenic lipoprotein remnants. This central role positions liver-specific molecular targets as critical therapeutic nodes for mitigating hyperlipidemia and halting atherosclerosis progression. The liver-specific protein Lzp (also named as OIT3), previously shown to stabilize apolipoprotein B (ApoB), the core structural component of triglyceride-rich lipoproteins, has an undefined role in vascular disease pathogenesis. Here, utilizing ApoE-/-mice, a well-established model that closely mimics human atherosclerosis, we demonstrate that Lzp deletion reduces plasma cholesterol, triglycerides, and ApoB levels under both chow and Western diets, concomitant with a marked attenuation of aortic plaque burden. Additionally, Lzp deficiency reduces hepatic and circulating ApoB levels in hyperlipidemic ApoE-/- mice, without exacerbating hepatic steatosis or injury. Mechanistically, Lzp ablation is anticipated to impair hepatic VLDL-ApoB secretion based on our previous findings, resulting in reduced circulating VLDL, intermediate density lipoprotein (IDL) and low-density lipoprotein (LDL) particles, attenuated lipid deposition, and suppressed macrophage-driven plaque inflammation. These results underscore the role of Lzp as a key regulator of systemic lipid metabolism and identify it as a potential candidate for further investigation toward therapeutic intervention of atherosclerotic cardiovascular disease.

Graphic abstract

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=128 SRC="FIGDIR/small/678175v1_ufig1.gif" ALT="Figure 1">
View larger version (36K):
org.highwire.dtl.DTLVardef@118ead8org.highwire.dtl.DTLVardef@e215baorg.highwire.dtl.DTLVardef@1007212org.highwire.dtl.DTLVardef@412757_HPS_FORMAT_FIGEXP  M_FIG C_FIG HightlightsO_LILzp deficiency attenuates atherosclerosis and improves plasma lipid profiles in ApoE-/- mice fed chow or Western diets.
C_LIO_LILzp deficiency reduces hepatic and circulating apolipoprotein B levels in hyperlipidemic ApoE-/- mice without exacerbating hepatic steatosis or injury.
C_LIO_LILzp represents a candidate therapeutic target, warranting further mechanistic and translational studies for atherosclerosis.
C_LI
]]></description>
<dc:creator>He, K.</dc:creator>
<dc:creator>Ku, X.</dc:creator>
<dc:creator>Chen, Z.</dc:creator>
<dc:creator>Wu, C.</dc:creator>
<dc:creator>Liao, C.</dc:creator>
<dc:creator>Li, L.</dc:creator>
<dc:creator>Qu, H.</dc:creator>
<dc:creator>Hong, P.</dc:creator>
<dc:creator>Bai, S.</dc:creator>
<dc:creator>Cui, X.</dc:creator>
<dc:creator>Su, X.</dc:creator>
<dc:creator>Han, Z.-G. K.</dc:creator>
<dc:date>2025-09-26</dc:date>
<dc:identifier>doi:10.1101/2025.09.24.678175</dc:identifier>
<dc:title><![CDATA[Lzp Ablation Ameliorates Dyslipidemia and Suppresses Atherosclerosis by Reducing Circulating Apolipoprotein B-Containing Lipoproteins]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.09.29.678898v1?rss=1">
<title>
<![CDATA[
De novo design of phospho-tyrosine peptide binders 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.09.29.678898v1?rss=1</link>
<description><![CDATA[
Phosphorylation on tyrosine is a key step in many signaling pathways. Despite recent progress in de novo design of protein binders, there are no current methods for designing binders that recognize phosphorylated proteins and peptides; this is a challenging problem as phosphate groups are highly charged, and phosphorylation often occurs within unstructured regions. Here we introduce RoseTTAFold Diffusion 2 for Molecular Interfaces (RFD2-MI), a deep generative framework for the design of binders for protein, ligand, and covalently modified protein targets. We demonstrate the power and versatility of this method by designing binders for four critical phosphotyrosine sites on three clinically relevant targets: Cluster of Differentiation 3 (CD3{varepsilon}), Epidermal Growth Factor Receptor (EGFR), Insulin Receptor (INSR) and Signal Transducer and Activator of Transcription 5 (STAT5). Experimental characterization shows that the designs bind their phosphotyrosine containing targets with affinities comparable to native binding sites and have negligible binding to non-phosphorylated targets or phosphopeptides with different sequences. X-ray crystal structures of generated binders to CD3{varepsilon} and EGFR are very close to the design models, demonstrating the accuracy of the design approach. A designed binder to an EGFR intracellular region phosphorylated upon EGF activation co-localizes with the receptor following EGF stimulation in single-particle tracking (SPT) experiments, demonstrating pY specific recognition in living cells. RFD2-MI provides a generalizable all-atom diffusion framework for probing and modulating phosphorylation-dependent signaling, and more generally, for developing research tools and targeted therapeutics against post-translationally modified proteins.
]]></description>
<dc:creator>Bauer, M. S.</dc:creator>
<dc:creator>Zhang, J. Z.</dc:creator>
<dc:creator>Wu, K.</dc:creator>
<dc:creator>Lee, G. R.</dc:creator>
<dc:creator>Coventry, B.</dc:creator>
<dc:creator>Klupt, K. A.</dc:creator>
<dc:creator>Shi, J.</dc:creator>
<dc:creator>Brent, R. I.</dc:creator>
<dc:creator>Li, X.</dc:creator>
<dc:creator>Moller, C.</dc:creator>
<dc:creator>Roullier, N.</dc:creator>
<dc:creator>Vafeados, D. K.</dc:creator>
<dc:creator>Kalvet, I.</dc:creator>
<dc:creator>Skotheim, R. K.</dc:creator>
<dc:creator>Zhu, S.</dc:creator>
<dc:creator>Motmaen, A.</dc:creator>
<dc:creator>Herrmann, L. C.</dc:creator>
<dc:creator>Sturmfels, P.</dc:creator>
<dc:creator>Tischer, D.</dc:creator>
<dc:creator>Altae-Tran, H. R.</dc:creator>
<dc:creator>Juergens, D.</dc:creator>
<dc:creator>Krishna, R.</dc:creator>
<dc:creator>Ahern, W.</dc:creator>
<dc:creator>Yim, J.</dc:creator>
<dc:creator>Bera, A. K.</dc:creator>
<dc:creator>Kang, A.</dc:creator>
<dc:creator>Joyce, E.</dc:creator>
<dc:creator>Lu, A.</dc:creator>
<dc:creator>Stewart, L.</dc:creator>
<dc:creator>DiMaio, F.</dc:creator>
<dc:creator>Baker, D.</dc:creator>
<dc:date>2025-09-30</dc:date>
<dc:identifier>doi:10.1101/2025.09.29.678898</dc:identifier>
<dc:title><![CDATA[De novo design of phospho-tyrosine peptide binders]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.01.679645v1?rss=1">
<title>
<![CDATA[
Flow Autoencoders are Effective Protein Tokenizers 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.01.679645v1?rss=1</link>
<description><![CDATA[
AO_SCPLOWBSTRACTC_SCPLOWProtein structure tokenizers enable the creation of multimodal models of protein structure, sequence, and function. Current approaches to protein structure tok-enization rely on bespoke components that are invariant to spatial symmetries, but that are challenging to optimize and scale. We present Kanzi, a flow-based tokenizer for tokenization and generation of protein structures. Kanzi consists of a diffusion autoencoder trained with a flow matching loss. We show that this approach simplifies several aspects of protein structure tokenizers: frame-based representations can be replaced with global coordinates, complex losses are replaced with a single flow matching loss, and SE(3)-invariant attention operations can be replaced with standard attention. We find that these changes stabilize the training of parameter-efficient models that outperform existing to- kenizers on reconstruction metrics at a fraction of the model size and training cost. An autoregressive model trained with Kanzi outperforms similar generative models that operate over tokens, although it does not yet match the performance of state-of-the-art continuous diffusion models. Code is available here: https://github.com/rdilip/kanzi/.
]]></description>
<dc:creator>Dilip, R.</dc:creator>
<dc:creator>Varshney, A.</dc:creator>
<dc:creator>Zhang, E.</dc:creator>
<dc:creator>Van Valen, D. A.</dc:creator>
<dc:date>2025-10-03</dc:date>
<dc:identifier>doi:10.1101/2025.10.01.679645</dc:identifier>
<dc:title><![CDATA[Flow Autoencoders are Effective Protein Tokenizers]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.01.679905v1?rss=1">
<title>
<![CDATA[
Pretrained protein language models choose between sequence novelty and structural completeness 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.01.679905v1?rss=1</link>
<description><![CDATA[
Protein language models (PLMs) have gained increasing acceptance in tasks ranging from variant effect prediction in disease to optimization and de novo design of proteins with improved stability, target-binding affinity, and catalytic performance. Despite encouraging performance in such applications, little is understood as far as the degree to which PLM-generated sequences - putative novel protein outputs - recapitulate the broad biophysical rules and diversity of sequence, structure, and function that defines natural protein-space, vital knowledge for boosting the design capacity of PLMs in ever-more-complex systems. Towards this end, we computationally profile and characterize the sequence and structure statistics and properties of hundreds of thousands of potential small proteins proposed through free unconstrained generation from architecturally distinct PLMs. We show that although these models exhibit a prodigious latent capacity to access novel amino-acid sequences, they struggle to approach the structural variation that exists on plain display in nature. Moreover, we uncover a stark tradeoff between prioritizing sequence novelty or structural breadth, exemplified by a "helical bundle trap" that dominates model output when aiming outside the comfortable bounds and evolutionary organization of natural sequences. These findings underscore a critical need for strategies that can rapidly guide PLMs into unlocking through generation the full richness of protein sequence, structure, and function that is consistent with governing biophysics but tantalizingly untapped as of yet in design contexts.

Author summaryLarge language models (LLMs) like GPT arent just for human text. Spinoff versions that treat protein and DNA sequences as special "languages" of their own, complete with preferred words and grammars, are being used to identify disease-causing genes and mutations and to design new treatments and drugs for clinical testing. But as anyone who has used an LLM chatbot has probably experienced at one time or another, these models can act narrow-minded or nonsensical, reducing their generality and utility. Protein language models are no exception to such flaws of reasoning. We show that protein language models face a fundamental choice between suggesting novel sequences that look nothing like natural ones and capturing the full range of three-dimensional shapes and structures responsible for the diverse functioning of molecular machines. Managing or bypassing this tradeoff is consequently of high import for designing proteins that impart novel functions and activities for therapeutic targeting and beyond.
]]></description>
<dc:creator>Subramanian, A. M.</dc:creator>
<dc:creator>Martinez, Z. A.</dc:creator>
<dc:creator>Thomson, M.</dc:creator>
<dc:date>2025-10-03</dc:date>
<dc:identifier>doi:10.1101/2025.10.01.679905</dc:identifier>
<dc:title><![CDATA[Pretrained protein language models choose between sequence novelty and structural completeness]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.03.680247v1?rss=1">
<title>
<![CDATA[
Mapping function in the tree shrew visual system using functional ultrasound imaging. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.03.680247v1?rss=1</link>
<description><![CDATA[
We adapted functional ultrasound imaging (fUSI) for awake, head-fixed northern tree shrews and used it to produce functional maps of visual processing at [~]100 {micro}m spatial resolution and [~]100 ms temporal resolution. Using classical retinotopic stimuli, full-field noise, motion localizers, and object versus scrambled object contrasts, we demonstrate robust, spatially specific hemodynamic responses across primary and extrastriate visual cortex, superior colliculus and subcortical structures. fUSI reliably reveals retinotopic reversals, laterality, and stimulus-selective modules, and yields high signal-to-noise %CBV changes that enable single-session mapping and targeting of electrophysiology or perturbations. These mesoscale maps provide a systems-level complement to recent high-density electrophysiological surveys of tree shrew visual cortex, which reported a compressed ventral-stream hierarchy and surprisingly early emergence of object coding in V2 (Lanfranchi et al., 2025). Together, our results establish fUSI as a powerful, scalable tool for functional mapping in the tree shrew, bridging large-scale circuit measurement and single-neuron electrophysiology and accelerating this species utility as a bridge between rodent genetics and primate vision.
]]></description>
<dc:creator>Wekselblatt, J. B.</dc:creator>
<dc:creator>Nayak, R.</dc:creator>
<dc:creator>lanfranchi, F.</dc:creator>
<dc:creator>Luongo, F.</dc:creator>
<dc:creator>Wagenaar, D. A.</dc:creator>
<dc:creator>Tsao, D. Y.</dc:creator>
<dc:creator>Shapiro, M.</dc:creator>
<dc:date>2025-10-03</dc:date>
<dc:identifier>doi:10.1101/2025.10.03.680247</dc:identifier>
<dc:title><![CDATA[Mapping function in the tree shrew visual system using functional ultrasound imaging.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.06.680687v1?rss=1">
<title>
<![CDATA[
Consistent Induction of Broadly Neutralizing HIV Antibodies by a Novel Two-Step Mechanism Informs Immunogen Design 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.06.680687v1?rss=1</link>
<description><![CDATA[
A major obstacle confronting HIV-1 vaccine and cure research is the lack of an outbred animal model for rapid and consistent induction of broadly neutralizing antibodies (bNAbs). We designed an epitope-focused simian-human immunodeficiency virus (SHIV.5MUT) that elicited broad and potent V3-glycan-targeted antibodies within a year of infection in 14 of 22 macaques compared with 0 of 14 control animals. SHIV.5MUT elicited bNAbs by a novel two-step mechanism, inducing an initial wave of V1-directed antibodies that selected for Envs with shortened, hypoglycosylated V1 loops, which in turn primed V3-glycan bNAb precursors. Rhesus bNAbs were immunogenetically and structurally diverse, closely resembling human V3-glycan bNAbs. Env-bNAb coevolution revealed a diverse repertoire of bNAb precursors and the Env variants that matured them, yielding a molecular blueprint for vaccine design.
]]></description>
<dc:creator>Skelly, A. N.</dc:creator>
<dc:creator>Gristick, H. B.</dc:creator>
<dc:creator>Li, H.</dc:creator>
<dc:creator>Gavor, E.</dc:creator>
<dc:creator>Connell, A. J.</dc:creator>
<dc:creator>Kreider, E. F.</dc:creator>
<dc:creator>Marchitto, L.</dc:creator>
<dc:creator>Hogarty, M. P.</dc:creator>
<dc:creator>Newby, M. L.</dc:creator>
<dc:creator>Allen, J. D.</dc:creator>
<dc:creator>Liu, W.</dc:creator>
<dc:creator>West, A. P.</dc:creator>
<dc:creator>Ayyanathan, K.</dc:creator>
<dc:creator>Campion, M. S.</dc:creator>
<dc:creator>Winters, K.</dc:creator>
<dc:creator>Gordon, C. G.</dc:creator>
<dc:creator>Osbaldeston, R. A.</dc:creator>
<dc:creator>Akeley, M. J.</dc:creator>
<dc:creator>Li, Y.</dc:creator>
<dc:creator>Singh, A.</dc:creator>
<dc:creator>Cruickshank, K.</dc:creator>
<dc:creator>Park, Y.</dc:creator>
<dc:creator>Zhao, C.</dc:creator>
<dc:creator>Li, X.</dc:creator>
<dc:creator>Amereh, K.</dc:creator>
<dc:creator>Van Itallie, E.</dc:creator>
<dc:creator>Carey, J. W.</dc:creator>
<dc:creator>Albertus, A.</dc:creator>
<dc:creator>DeLaitsch, A. T.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>Lituchy, M. G.</dc:creator>
<dc:creator>Walsh, A. A.</dc:creator>
<dc:creator>Morris, D. J.</dc:creator>
<dc:creator>Habib, R.</dc:creator>
<dc:creator>Bibollet-Ruche, F.</dc:creator>
<dc:creator>Mishra, N.</dc:creator>
<dc:creator>Avillion, G.</dc:creator>
<dc:creator>Koranda, N. S.</dc:creator>
<dc:creator>Plante, S. J.</dc:creator>
<dc:creator>Martella, C. L.</dc:creator>
<dc:creator>Lora, J.</dc:creator>
<dc:creator>Wang, E. J. D.</dc:creator>
<dc:creator>Lewis, M. G</dc:creator>
<dc:date>2025-10-06</dc:date>
<dc:identifier>doi:10.1101/2025.10.06.680687</dc:identifier>
<dc:title><![CDATA[Consistent Induction of Broadly Neutralizing HIV Antibodies by a Novel Two-Step Mechanism Informs Immunogen Design]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.08.680157v1?rss=1">
<title>
<![CDATA[
ATM promotes reversed fork processing during DNA interstrand cross-link repair 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.08.680157v1?rss=1</link>
<description><![CDATA[
During replication-coupled DNA interstrand cross-link (ICL) repair, fork reversal is thought to enable the Fanconi anemia (FA) pathway to resolve the ICL through nucleolytic incisions. Subsequent fork restoration then allows nascent DNA strand extension past the lesion. Although these fork remodeling events are crucial for ICL repair, their regulation remains poorly understood. Here, we use cell-free Xenopus egg extracts to investigate fork dynamics during ICL repair by the FA pathway. We find that the ataxia telangiectasia-mutated (ATM) kinase is activated concomitantly with fork reversal and promotes resection of the reversed fork intermediate. This resection depends on the coordinated activities of the EXO1 and DNA2 nucleases. Our data indicate that EXO1 initiates 5 to 3 resection of nascent lagging strands in the regressed arm, while DNA2 performs 5 to 3 resection of recessed lagging strands. We further show that the inhibition of protein phosphatase 2A (PP2A) during ICL repair results in ATM hyperactivation, reversed fork over-resection, and formation of aberrant end-joining products, indicating that PP2A counteracts ATM signaling to constrain reversed fork resection. Taken together, this work implicates reversed forks as substrates for ATM activation and reveals a phospho-regulatory circuit that governs reversed fork processing during ICL repair.
]]></description>
<dc:creator>Altshuller, M.</dc:creator>
<dc:creator>MacKrell, V. A.</dc:creator>
<dc:creator>Tzeng, J.</dc:creator>
<dc:creator>Nigam, R.</dc:creator>
<dc:creator>Wang, T.-Y.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Semlow, D. R.</dc:creator>
<dc:date>2025-10-09</dc:date>
<dc:identifier>doi:10.1101/2025.10.08.680157</dc:identifier>
<dc:title><![CDATA[ATM promotes reversed fork processing during DNA interstrand cross-link repair]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.09.681420v1?rss=1">
<title>
<![CDATA[
Plasmidome, resistome, and virulence-associated genes characterization of Acinetobacter johnsonii in NASA cleanrooms and a clinical setting. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.09.681420v1?rss=1</link>
<description><![CDATA[
Evidence shows persistence of non-spore-forming Acinetobacter johnsonii in high-stakes controlled and nutrient-limited environments. This study aims to explore the mechanisms underpinning such adaptability through a comprehensive genomic analysis of 22 isolates of A. johnsonii from NASAs Payload Hazardous Servicing Facility (PHSF) and one carbapenem-resistant strain (E154408A) from patient colonization in Ireland. Core-genome phylogeny revealed clustering of PHSF-originating isolates in a monophyletic clade divergent from the main species lineage. Species-wide virulence-associated genes and metabolic profiling indicated the unique presence in PHSF-originating isolates of two complete efflux pumps and of a conserved allantoin racemase, suggesting adaptability for multiple environmental stresses. Observed ubiquity of blaOXA in investigated genomes (n=112) and phenotypically-validated multidrug-resistant profile of E154408A strain highlight A. johnsoniis potential as antimicrobial resistance (AMR) reservoir. Plasmidome analysis suggested gain/loss events across the monophyletic population and potential AMR acquisition pathways. Genome-to-metagenome mapping identified genomic signatures of A. johnsonii in PHSF >10 years post initial isolation.

ImportanceAcinetobacter johnsonii is increasingly recognized as an emerging human pathogen, with growing evidence of its ability to persist in controlled, high-stakes environments, posing risks as both persisting environmental contaminant and antimicrobial resistance (AMR) reservoir. Yet, gaps remain in our understanding of its AMR profile and the mechanisms that enable its enhanced environmental adaptability. This knowledge is necessary in contexts where biological cleanliness is a priority such as clinical settings and spacecraft assembly facilities cleanrooms, where contamination of hardware with terrestrial microorganisms is concerning. In this study, we aim to address some of key knowledge gaps by providing genomic insights into a rare multi-drug resistant clinical isolate and 22 NASA cleanroom isolates that persisted for over a decade in extremely clean conditions. Our findings will help evaluate the contamination risk of A. johnsonii in high-stakes environments and ultimately strengthen our ability to manage this microbial contaminant across terrestrial and extraterrestrial settings.

HighlightsO_LICleanrooms-derived A. johnsonii genomes show favorable traits for increased adaptability
C_LIO_LIGenomic signatures of A. johnsonii persisted in the cleanrooms for >10 years
C_LIO_LIblaOXA is ubiquitously found in the genome of all A. johnsonii
C_LIO_LIE154408A is the first patient colonization by carbapenem-resistant A. johnsonii in Europe
C_LI
]]></description>
<dc:creator>Tumeo, A.</dc:creator>
<dc:creator>Miliotis, G.</dc:creator>
<dc:creator>O'Connor, A.</dc:creator>
<dc:creator>Vijayakumar, V.</dc:creator>
<dc:creator>Sengupta, P.</dc:creator>
<dc:creator>McDonagh, F.</dc:creator>
<dc:creator>Kovarova, A.</dc:creator>
<dc:creator>Clarke, C.</dc:creator>
<dc:creator>Hooban, B.</dc:creator>
<dc:creator>Singh, N. K.</dc:creator>
<dc:creator>Rosado, A. S.</dc:creator>
<dc:creator>Raman, K.</dc:creator>
<dc:creator>Venkateswaran, K.</dc:creator>
<dc:date>2025-10-10</dc:date>
<dc:identifier>doi:10.1101/2025.10.09.681420</dc:identifier>
<dc:title><![CDATA[Plasmidome, resistome, and virulence-associated genes characterization of Acinetobacter johnsonii in NASA cleanrooms and a clinical setting.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.10.681681v1?rss=1">
<title>
<![CDATA[
The neural computations underlying context dependent attribute-based valuation of complex stimuli. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.10.681681v1?rss=1</link>
<description><![CDATA[
Adaptive decision making requires value computations to be flexible because we often need to value a stimulus differently as the context changes. A stimulus might be highly desirable in one context but completely unappealing in another. However, it is not known how the brain can support such flexible modulation of overall stimulus value. Here we test a model of flexible value construction whereby individual attributes of a stimulus are converted into contextually dependent attribute-specific value representations before being combined into an overall integrated stimulus value. To test this framework, human participants (online n=95, MRI n=35) provided ratings for 75 unique high-dimensional clothing stimuli under three instructed  goal-contexts designed to elicit differences in overall value judgments for the items. Integrated value ratings for each stimulus were found to be goal-context dependent, while individual stimulus-attributes varied markedly in how they contributed to value ratings across goal contexts. In the fMRI data, representations of the absolute levels of particular attributes were revealed in visual areas. In contrast, encoding of individual attributes in value space, alongside integrated overall stimulus value, was present within distinct regions of prefrontal cortex. More specifically, behaviorally relevant attributes in value space and integrated stimulus value were found in vmPFC and dmPFC respectively. These findings indicate that the construction of value for high-dimensional stimuli is achieved through the computation of goal-context-dependent attributes in value space, providing mechanistic insight into how the brain can flexibly modulate stimulus-values as context changes.
]]></description>
<dc:creator>Fransen, A.</dc:creator>
<dc:creator>Man, V.</dc:creator>
<dc:creator>Iigaya, K.</dc:creator>
<dc:creator>O`Doherty, J. P.</dc:creator>
<dc:date>2025-10-12</dc:date>
<dc:identifier>doi:10.1101/2025.10.10.681681</dc:identifier>
<dc:title><![CDATA[The neural computations underlying context dependent attribute-based valuation of complex stimuli.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.14.682373v1?rss=1">
<title>
<![CDATA[
Electrical synapses mediate visual approach behavior 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.14.682373v1?rss=1</link>
<description><![CDATA[
Detecting salient visual objects and orienting toward them are commonplace tasks for animals, yet the underlying neural circuits remain poorly understood. The fruit fly is an ideal model for a comprehensive analysis of feature detection mechanisms given its complete synaptic wiring diagrams, robust behavioral assays, and cell-type-specific gene expression datasets. We previously showed that columnar T3 neurons are required for saccadic orientation toward landscape features during flight. Here, we examine how signals downstream of T3 are processed in the central brain. We identify LC17 visual projection neurons as key postsynaptic targets: they receive strong excitatory input from T3, project to premotor brain regions, and are thus positioned to support visual approach. Using in vivo optical physiology and virtual reality behavior, we demonstrate that LC17 neurons are indeed necessary for object tracking during flight. Furthermore, we find that electrical synapses in LC17 are also required for tracking behavior. We show that the innexin Shaking B (shakB) is highly expressed in LC17 and localized to its dendrites, and genetic perturbations confirm its essential role for electrical coupling in this circuit. Our findings reveal mechanisms underlying visual approach, and highlight the interplay between electrical and chemical neurotransmission for rapid object detection and action selection.
]]></description>
<dc:creator>Frighetto, G.</dc:creator>
<dc:creator>Dombrovski, M.</dc:creator>
<dc:creator>Castillo, L. M. P.</dc:creator>
<dc:creator>Meera, P.</dc:creator>
<dc:creator>Mirshahidi, P. S.</dc:creator>
<dc:creator>Sanfilippo, P.</dc:creator>
<dc:creator>Vaccari, A.</dc:creator>
<dc:creator>Kandimalla, P.</dc:creator>
<dc:creator>Hartenstein, V.</dc:creator>
<dc:creator>Kurmangaliyev, Y. Z.</dc:creator>
<dc:creator>Zipursky, S. L.</dc:creator>
<dc:creator>Frye, M. A.</dc:creator>
<dc:date>2025-10-15</dc:date>
<dc:identifier>doi:10.1101/2025.10.14.682373</dc:identifier>
<dc:title><![CDATA[Electrical synapses mediate visual approach behavior]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.14.682417v1?rss=1">
<title>
<![CDATA[
Natural evolution of intermale sexual behavior by multiple pheromone switches among Drosophila species 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.14.682417v1?rss=1</link>
<description><![CDATA[
We have identified a Drosophila species which exhibits spontaneous and robust intermale sexual behavior. D. santomea males distinguish conspecific sexes but court both vigorously and seldom attack. Elevated intermale courtship stems from at least three evolutionarily derived pheromonal changes. In males, the sexually monomorphic cuticular pheromone 7-tricosene promotes rather than inhibits courtship and the courtship-inhibiting olfactory pheromone cVA is reduced 84-92% compared to close relatives. The third switch is in D. santomea females, where cVA suppresses rather than promotes sexual receptivity. Female cVA aversion and male cVA reduction may have co-evolved to maintain efficient intraspecific mating but prevent hybridization with the sympatric sibling species D. yakuba. High intermale courtship and low cVA also co-occur and appear selectively derived in a distant monomorphic species D. persimilis, implying pheromonal and social behavioral convergence. Changes in pheromone valence and levels may therefore explain the recent evolutionary emergence of intermale sexual behavior in Drosophila.
]]></description>
<dc:creator>Ouadah, Y.</dc:creator>
<dc:creator>Naragon, T. H.</dc:creator>
<dc:creator>Smihula, H.</dc:creator>
<dc:creator>Behrman, E. L.</dc:creator>
<dc:creator>Khallaf, M. A.</dc:creator>
<dc:creator>Ding, Y.</dc:creator>
<dc:creator>Stern, D. L.</dc:creator>
<dc:creator>Parker, J.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:date>2025-10-15</dc:date>
<dc:identifier>doi:10.1101/2025.10.14.682417</dc:identifier>
<dc:title><![CDATA[Natural evolution of intermale sexual behavior by multiple pheromone switches among Drosophila species]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.14.682448v1?rss=1">
<title>
<![CDATA[
CRISPR-Cas9 based Mutagenesis in the Entomopathogenic Nematode Steinernema hermaphroditum and the Maintenance of Mutant Lines 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.14.682448v1?rss=1</link>
<description><![CDATA[
Entomopathogenic nematodes (EPNs) from the genus Steinernema and Heterorhabditis form mutualistic relationships with symbiotic bacteria from the genus Xenorhabdus and Photorhabdus, respectively. Together, these nematode-bacterium pairs infect and kill insect hosts--primarily larvae from the orders Lepidoptera and Coleoptera. This tripartite interaction provides a powerful model for investigating the molecular mechanisms underlying mutualism and parasitism. A key step toward this goal is the development of a genetically tractable EPN. While RNAi has been applied in some EPN species, stable, transgenerational genetic tools remain limited. Here, we establish a robust CRISPR-Cas9 system in the emerging model Steinernema hermaphroditum, a species that is easily cultivated in both in vivo and in vitro conditions and amenable to gonadal microinjection. Notably, its hermaphroditic reproduction simplifies the generation of genetically stable mutant lines. We present a detailed protocol for efficient, targeted gene knockout via microinjection in S. hermaphroditum. As a proof-of-concept, we knocked out a conserved homologue, unc-22, which causes a twitching phenotype. The CRISPR-Cas9 based genome editing in S. hermaphroditum has potential to be used to express transgene, or to be adapted to other EPN species that are applicable to benefit agriculture.

SUMMARYThis article demonstrates CRISPR-Cas9 mediated genome engineering in Steinernema hermaphroditum, an entomopathogenic (EPN: insect-parasitic) nematode and an emerging genetic model. The described technology is useful for creating mutants allowing for the elucidation of gene functions in the nematode biology that is relevant to mutualistic and parasitic symbiosis.
]]></description>
<dc:creator>Ireri, S. W.</dc:creator>
<dc:creator>Cao, M.</dc:creator>
<dc:date>2025-10-15</dc:date>
<dc:identifier>doi:10.1101/2025.10.14.682448</dc:identifier>
<dc:title><![CDATA[CRISPR-Cas9 based Mutagenesis in the Entomopathogenic Nematode Steinernema hermaphroditum and the Maintenance of Mutant Lines]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.15.682532v1?rss=1">
<title>
<![CDATA[
Survival of NASA-cleanroom microbial isolates under simulated space and Martian conditions 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.15.682532v1?rss=1</link>
<description><![CDATA[
Planetary protection hinges on understanding microbial survival following sterilization procedures, the stressors of space travel, and exposure to extraterrestrial environmental conditions. This study identified 23 fungal strains isolated from NASA-spacecraft assembly cleanrooms, capable of surviving ultraviolet radiation exposure. Using experimental simulation facilities, we conducted a comprehensive assessment of microbial survivability and morphology on the most resilient spacecraft-associated microorganisms.

Aspergillus calidoustus demonstrated remarkable survival under simulated Martian conditions, withstanding up to 1440 minutes of Martian solar irradiation, Mars atmospheric pressure and composition, and the presence of Martian regolith. Lethality only occurred under combined irradiation and cooling to -60{degrees}C (the mean Mars surface temperature), emphasising the synergistic effect of these conditions. Furthermore, A. calidoustus survived long-duration neutron radiation exposure (replicating ionizing space radiation doses) and dry-heat sterilization (typically used for spacecraft components).

This is the first study to perform an end-to-end evaluation of eukaryotic microbial survival across conditions that occur during preparation for, travel to, and robotic exploration of Mars. The experimental facilities and chronic exposure methods utilized offer a biologically meaningful model for understanding microbial risks during long-duration space missions. The capacity for fungal conidia to survive multiple space-relevant conditions suggests their potential as forward contaminants, capable of being transported to and persisting on Mars. As current spacecraft sterilization protocols prioritize bacterial spores, this research highlights a critical gap in planetary protection strategies. In addition to offering novel insights into microbial survival and dispersal, these findings have broader implications for biocontamination within the food, pharmaceutical, and medical sectors.

ImportanceThis study reveals that conidia / spores of a fungus Aspergillus calidoustus, which was isolated from spacecraft assembly cleanrooms, can survive simulated space-relevant stressors like ultraviolet irradiation, Martian cold atmospheric pressure, regolith exposure, ionizing radiation and specific doses of recommended dry heat sterilization for spacecrafts. Such fungal resilience demonstrates that the species can survive certain space and Mars conditions previously thought to be sterilizing, highlighting a need to revise current spacecraft decontamination standards that focus mainly on bacterial spores. This study also highlights the need for continued microbial monitoring of spacecrafts during transit from Earth to other planets not only to achieve goals of planetary protection but also to maintain healthy closed system for manned missions. Moreover, it is also alarming for an Earth origin fungal species due to biocontamination risks for food, medical, and pharmaceutical industries may require need for new standards of sterilization approaches transferable to space exploration.
]]></description>
<dc:creator>Chander, A. M.</dc:creator>
<dc:creator>Burr, D. J.</dc:creator>
<dc:creator>Wipf, S.</dc:creator>
<dc:creator>Nitsche, R.</dc:creator>
<dc:creator>Fujimura, G.</dc:creator>
<dc:creator>Schubert, W. W.</dc:creator>
<dc:creator>Kumar Singh, N.</dc:creator>
<dc:creator>Bell, J.</dc:creator>
<dc:creator>Brandl, A.</dc:creator>
<dc:creator>Weil, M. M.</dc:creator>
<dc:creator>Elsaesser, A.</dc:creator>
<dc:creator>Venkateswaran, K.</dc:creator>
<dc:date>2025-10-15</dc:date>
<dc:identifier>doi:10.1101/2025.10.15.682532</dc:identifier>
<dc:title><![CDATA[Survival of NASA-cleanroom microbial isolates under simulated space and Martian conditions]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.16.682381v1?rss=1">
<title>
<![CDATA[
Shifts in ruminant fermentation during inhibition of methanogenesis are reflected in the isotope compositions of volatile fatty acids. 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.16.682381v1?rss=1</link>
<description><![CDATA[
Ruminant animals are a major source of the potent greenhouse gas methane, but they are also a tractable target for climate solutions. Several strategies have been developed to lower methane emissions from ruminants, including feed additives that inhibit methanogenic archaea. Sustainable solutions must eliminate methane emissions without hampering the microbial fermentation of plant material, which the animal host relies on for carbon and energy. However, current tools cannot directly quantify or characterize the metabolic pathways of in vivo ruminant fermentation. To fill this gap, we developed an electrospray (ESI) Orbitrap mass spectrometry technique to measure the stable isotope ratios (13C /12C and 2H/1H) of volatile fatty acids (VFAs) at their natural isotopic abundances directly from rumen fluid. We tested this technique on in vitro incubations of rumen fluid fed three different substrates with and without the additive Asparagopsis taxiformis. We found that the isotope composition of VFAs changed and reflected a remodeling of microbial fermentation pathways. Specifically, acetates{delta} 13C value increased when methanogens were inhibited, suggesting a lower relative rate of acetate synthesis and a lack of acetogenic activity. Furthermore, the{delta} 2H value of propionate decreased, which may indicate a change in the balance between the two pathways of propionate synthesis toward the less energetic acrylate pathway. Both signals were consistent across feed types. Taken together, our results provide evidence that fermentative metabolism is remodeled during methanogenesis inhibition and decreases relative fluxes through ATP-generating pathways. More broadly, this study demonstrates the utility of ESI-Orbitrap-based isotopic analysis for studying rumen microbial ecology.

IMPORTANCESlowing methane production from ruminant animals (e.g. cows) is a major target for mitigation of anthropogenic climate change. While strategies that eliminate microorganisms producing methane have been successful, they have cascading impacts on the microbial ecology of the rumen, possibly affecting animal health and productivity.



O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=99 SRC="FIGDIR/small/682381v1_ufig1.gif" ALT="Figure 1">
View larger version (23K):
org.highwire.dtl.DTLVardef@1368f20org.highwire.dtl.DTLVardef@ee87baorg.highwire.dtl.DTLVardef@10f714org.highwire.dtl.DTLVardef@1cd4f6a_HPS_FORMAT_FIGEXP  M_FIG C_FIG Of particular importance is microbial fermentation, which generates easily digested volatile fatty acids (VFAs) from hard-to-breakdown plant matter. To better understand how fermentation responds to methane mitigation strategies, we measured the isotope composition of VFAs in cow rumen. Our results indicate that fermentation changes pathways when methane production is inhibited to those that generate less energy for the cell. As methane mitigation strategies are developed in the coming decade, isotopic analysis of VFAs may be a useful and accessible contribution to our understanding of rumen microbiology.
]]></description>
<dc:creator>Mueller, E.</dc:creator>
<dc:creator>Duong, R.</dc:creator>
<dc:creator>Sessions, A.</dc:creator>
<dc:creator>Eiler, J.</dc:creator>
<dc:creator>Hess, M.</dc:creator>
<dc:date>2025-10-16</dc:date>
<dc:identifier>doi:10.1101/2025.10.16.682381</dc:identifier>
<dc:title><![CDATA[Shifts in ruminant fermentation during inhibition of methanogenesis are reflected in the isotope compositions of volatile fatty acids.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.16.682711v1?rss=1">
<title>
<![CDATA[
A line attractor maintains aggressiveness during feeding in hangry mice 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.16.682711v1?rss=1</link>
<description><![CDATA[
Aggression evolved to protect resources such as food from competitors, but animals must balance fighting and feeding so that they facilitate rather than hinder re-establishment of energy homeostasis. How this balancing is computed is not well understood. We have approached this problem at the level of neural population-coding by examining the effect of progressive starvation on a hypothalamic line attractor that encodes an internal state of aggressiveness. Moderate fasting yielded "hangry" mice, decreasing attack latency and increasing attack frequency. In parallel, line attractor ramping rate and stability were increased, suggesting that hunger enhances aggressiveness by modifying neural dynamics. In contrast, prolonged starvation inhibited aggression and eliminated the line attractor. In satiated mice, titrated acute chemogenetic activation of arcuate AgRP neurons recapitulated the biphasic effects of progressive starvation, suggesting that a continuous increase in hunger exerts bi-directional influences at different intensities. When confronted with food and an intruder, hangry mice alternated between feeding and fighting. During eating, population neural activity moved out of the line attractor while activity in the attractor dimension remained unchanged. Following feeding, activity rapidly relaxed back into the attractor and aggression resumed. Thus, the line attractor may serve to keep hungry animals primed for aggression during intermittent feeding bouts.
]]></description>
<dc:creator>Kim, J. J.</dc:creator>
<dc:creator>Nair, A.</dc:creator>
<dc:creator>Coria, N.</dc:creator>
<dc:creator>Huynh, S.</dc:creator>
<dc:creator>Vinograd, A.</dc:creator>
<dc:creator>Xu, J.</dc:creator>
<dc:creator>Liu, M.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:date>2025-10-17</dc:date>
<dc:identifier>doi:10.1101/2025.10.16.682711</dc:identifier>
<dc:title><![CDATA[A line attractor maintains aggressiveness during feeding in hangry mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.21.683747v1?rss=1">
<title>
<![CDATA[
mRNA delivery of genetically encoded mosaic-8 pan-sarbecovirus RBD vaccines 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.21.683747v1?rss=1</link>
<description><![CDATA[
Effective pan-sarbecovirus vaccines could prevent future zoonotic spillovers of SARS-like betacoronaviruses. We previously developed protein-based mosaic-8 nanoparticles displaying eight diverse sarbecovirus RBDs, either individually (mosaic-8 RBD-NPs) or as two "quartets" of four tandemly-arranged RBDs (dual-quartet RBD-NPs), which elicited broadly cross-reactive antibodies but require multi-component manufacturing. Here, we address scalability challenges by extending the mosaic-8 concept to mRNA by encoding membrane-bound RBD quartets as dual-quartet RBD-mRNA and dual-quartet RBD-EABR-mRNA, the latter leveraging ESCRT- and ALIX-binding region (EABR) technology for immunogen display on cell surfaces and secreted virus-like particles. Compared with protein-based mosaic-8 immunogens, mRNA-encoded mosaic-8 vaccines induced equivalent or enhanced antibody breadth, neutralization potencies, T-cell responses, and targeting of conserved RBD epitopes. In addition, mRNA-encoded mosaic-8 vaccines elicited more balanced IgG subclass profiles and increased Fc{gamma} receptor-binding IgGs, consistent with potentially superior Fc effector functions. These findings demonstrate successful translation of mosaic-8 RBD-NPs into mRNA/EABR-mRNA vaccines, enabling scalable manufacturing and improving protection against future sarbecovirus outbreaks. Finally, our newly developed technique, Systems Serology-Polyclonal Epitope Mapping (SySPEM), revealed distinct IgG-subclass-specific epitope signatures across mRNA, EABR-mRNA, and protein vaccines, demonstrating that the mode of antigen display can shape epitope recognition.

SummaryWe translated a pan-sarbecovirus RBD vaccine from protein nanoparticles to scalable mRNA and EABR-mRNA platforms encoding RBD quartets. Compared with protein-based immunogens, mRNA-based vaccines matched or improved antibody breadth, T-cell responses, Fc functionality, and conserved epitope targeting. A newly-developed Systems Serology-Polyclonal Epitope Mapping (SySPEM) technique revealed that antigen presentation modality shapes IgG subclass-specific epitope recognition.
]]></description>
<dc:creator>Cohen, A. A.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>Manasyan, L.</dc:creator>
<dc:creator>Madireddy, I.</dc:creator>
<dc:creator>Fils, A.-C. I. P.</dc:creator>
<dc:creator>Dam, K.-M. A.</dc:creator>
<dc:creator>Stober, H. E.</dc:creator>
<dc:creator>Hills, R. A.</dc:creator>
<dc:creator>Moon, W. J.</dc:creator>
<dc:creator>Lin, P. J. C.</dc:creator>
<dc:creator>Howarth, M. R.</dc:creator>
<dc:creator>Hoffmann, M. A. G.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:date>2025-10-22</dc:date>
<dc:identifier>doi:10.1101/2025.10.21.683747</dc:identifier>
<dc:title><![CDATA[mRNA delivery of genetically encoded mosaic-8 pan-sarbecovirus RBD vaccines]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.24.684421v1?rss=1">
<title>
<![CDATA[
MillionFull enables massive, full-length enzyme sequence-fitness data collection at low cost for machine learning-guided enzyme engineering 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.24.684421v1?rss=1</link>
<description><![CDATA[
Machine learning holds great promise for accelerating enzyme optimization, but its power is fundamentally constrained by the limited availability of sequence-fitness data. Here, we introduce MillionFull, a low-cost method that enables high-throughput full-length sequence- fitness mapping for enzymes of arbitrary length. Each run yields on the order of 10-10 data points, capturing sequence-function relationships at unprecedented scale. By overcoming the data bottleneck, MillionFull provides a foundation for dramatically advancing AI-driven enzyme engineering.
]]></description>
<dc:creator>Li, J.</dc:creator>
<dc:creator>Erichsen, B.</dc:creator>
<dc:creator>Krarup, S. R.</dc:creator>
<dc:creator>Yuan, S.</dc:creator>
<dc:creator>Jijakli, K.</dc:creator>
<dc:creator>Karst, S.</dc:creator>
<dc:creator>Yang, L.</dc:creator>
<dc:creator>Nielsen, A. T.</dc:creator>
<dc:date>2025-10-25</dc:date>
<dc:identifier>doi:10.1101/2025.10.24.684421</dc:identifier>
<dc:title><![CDATA[MillionFull enables massive, full-length enzyme sequence-fitness data collection at low cost for machine learning-guided enzyme engineering]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.25.684556v1?rss=1">
<title>
<![CDATA[
Neural control of coordinated wing and leg movements during a terrestrial threat display 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.25.684556v1?rss=1</link>
<description><![CDATA[
Threat displays are a common form of social communication. In flying species, such displays often involve stereotypical, choreographed wing and leg movements. How the brain coordinates characteristic movements of these appendages to transmit social signals is poorly understood. In male Drosophila, threat displays flexibly combine wing displays with rapid turns and charges. Here we identify two brain modules downstream of a superordinate threat command center. Each contains two neurons that combinatorially generate threat-specific appendicular movements: one comprises two descending neurons synergistically controlling wing threat; the other contains two interneurons that antagonistically control turns and charges. Within-module neuronal coactivation evokes appendage-specific actions recapitulating those evoked by the upstream center. These data uncover a hierarchical combinatorial circuit that coordinates wing and leg movements during a terrestrial social display. More generally, our findings identify an instantiation of a Tinbergenian hierarchical behavioral control system for social communication and reveal a novel underlying implementation logic.
]]></description>
<dc:creator>Cao, S.</dc:creator>
<dc:creator>Anderson, D. J.</dc:creator>
<dc:date>2025-10-26</dc:date>
<dc:identifier>doi:10.1101/2025.10.25.684556</dc:identifier>
<dc:title><![CDATA[Neural control of coordinated wing and leg movements during a terrestrial threat display]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.27.684971v1?rss=1">
<title>
<![CDATA[
Determining Multivalent Interactomes of Intrinsically Disordered Proteins in Phase-Separated Condensates in Live Cells 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.27.684971v1?rss=1</link>
<description><![CDATA[
Many intrinsically disordered protein regions (IDRs) can form liquid-liquid phase separation (LLPS) condensates via multivalent interactions, but how the interaction behaviors contribute to specific cellular functions remains unclear due to the unknown composition of the condensates. Here, we report phase-separation-induced interactome detection (PhaseID), a new method that determines the protein components within the LLPS condensates driven by any given IDR in live human cells. Using PhaseID, we demonstrated that transactivation IDRs each have unique multivalent interactomes, thereby executing transactivation through distinct pathways. In-depth analyses of PhaseID-determined IDR interactomes revealed that LLPS tunes the interaction selectivity of IDRs, enabling them to play new roles in specific cellular processes, and different LLPS condensates recruit proteins with distinct physicochemical properties encoded in their sequences.
]]></description>
<dc:creator>Han, Q.</dc:creator>
<dc:creator>Zhong, Y.</dc:creator>
<dc:creator>Quan, B.</dc:creator>
<dc:creator>Wang, T.-Y.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Chong, S.</dc:creator>
<dc:date>2025-10-28</dc:date>
<dc:identifier>doi:10.1101/2025.10.27.684971</dc:identifier>
<dc:title><![CDATA[Determining Multivalent Interactomes of Intrinsically Disordered Proteins in Phase-Separated Condensates in Live Cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.28.685245v1?rss=1">
<title>
<![CDATA[
Spatiotemporal Microbial Ecoevolutionary Dynamics on the International Space Station 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.28.685245v1?rss=1</link>
<description><![CDATA[
This study presents the most comprehensive spatiotemporal analysis of the ISS microbiome to date. Over a seven-year period, 184 surface samples were collected for live/dead metagenomic profiling, phenotypic characterization of antimicrobial resistance (AMR) and virulence among 102 cultured isolates, and metagenome-assembled genome (MAG) analysis to evaluate evolutionary selection pressures. Despite ecological stability, comparative genomics revealed ongoing microevolution through lateral gene transfer and selection for traits (e.g., radiation resistance and biocide tolerance). Importantly, predictions of AMR and virulence frequently misaligned with experimental outcomes, underscoring the need for functional validation. This dataset highlights a stable core microbiome that persists across years, punctuated by localized adaptation and gene flow. The ISS microbiome exemplifies both ecological resilience and microevolutionary innovation that can inform risk management for long-duration spaceflight.
]]></description>
<dc:creator>Hill, M. S.</dc:creator>
<dc:creator>Simpson, A. C.</dc:creator>
<dc:creator>Minnis, V.</dc:creator>
<dc:creator>Salas Garcia, M. C.</dc:creator>
<dc:creator>Mahnert, A.</dc:creator>
<dc:creator>Lax, S.</dc:creator>
<dc:creator>Rushton, E.</dc:creator>
<dc:creator>Chung, R.</dc:creator>
<dc:creator>Bone, D.</dc:creator>
<dc:creator>Parker, C. W.</dc:creator>
<dc:creator>Allard, S. M.</dc:creator>
<dc:creator>Matty, M.</dc:creator>
<dc:creator>Venkateswaran, K.</dc:creator>
<dc:creator>Gilbert, J. A.</dc:creator>
<dc:date>2025-10-29</dc:date>
<dc:identifier>doi:10.1101/2025.10.28.685245</dc:identifier>
<dc:title><![CDATA[Spatiotemporal Microbial Ecoevolutionary Dynamics on the International Space Station]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.29.685462v1?rss=1">
<title>
<![CDATA[
Trimodal brain-wide ultrasound imaging of brain-tumor interaction 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.29.685462v1?rss=1</link>
<description><![CDATA[
Patients with brain tumors often suffer debilitating neurological dysfunction as their tumors disrupt brain tissue, affecting both local and global neural activity and blood flow. However, studying tumor-brain interactions in animal models is challenging due to a lack of methods that simultaneously capture dynamics of tumor growth, neural activity and vascular alterations over time. Here, we overcome this limitation using a multimodal ultrasound imaging platform, an imaging technique that offers brain-wide coverage in living animals at 10-100 {micro}m resolution. To monitor the co-evolution of tumor growth, neural activity and vascular remodeling, we integrated (1) nonlinear imaging of acoustic reporter gene expressing-tumors, (2) hemodynamic functional imaging of brain activity, and (3) super-resolution microscopy of the vasculature. Integrating these modalities for the first time and applying them to a common model of glioblastoma, we followed tumor-brain interactions in individual animals over their disease lifetimes. Our approach allowed us to precisely map the spatial displacement of functional brain regions, the local and global disruption of functional connectivity, and the remodeling of the blood supply to support tumor growth. This integrated method bridges a critical gap in brain cancer research and therapy development by providing a unified dynamic view of what happens to the brain as tumors grow within it.
]]></description>
<dc:creator>Rabut, C.</dc:creator>
<dc:creator>Shivaei, S.</dc:creator>
<dc:creator>Heiles, B.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2025-10-31</dc:date>
<dc:identifier>doi:10.1101/2025.10.29.685462</dc:identifier>
<dc:title><![CDATA[Trimodal brain-wide ultrasound imaging of brain-tumor interaction]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.10.30.685465v1?rss=1">
<title>
<![CDATA[
Fine-tuned Protein Language Model Identifies Antigen-specific B Cell Receptors from Immune Repertoires 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.10.30.685465v1?rss=1</link>
<description><![CDATA[
Scalable identification of antigen-specific antibodies from whole immune repertoire V(D)J sequences is a central challenge in biomedical engineering. We show that protein language models (PLMs) fine-tuned on antibody heavy-chain sequences can directly predict antigen specificity from unselected immune repertoires. We assessed our model, Antigen Specificity Predictor (ASPred), against SARS-CoV-2, influenza, and HIV-AIDS antigens, observing comparable predictive performance. In the whole immune repertoire V(D)J sequences of mice immunized with the SARS-CoV-2 spike proteins receptor-binding domain (RBD), ASPred identified antibody sequences specific to RBD. Several candidate sequences were validated, including one as a heavy chain-only nanobody with 20.7 nM dissociation constant. Molecular dynamics simulations supported the predicted interactions at coarse-grained and atomic levels. Benchmarking against Barcode-Enabled Antigen Mapping (BEAM) of B cell receptor sequence data had highly significant overlaps with ASPred predictions, suggesting scalability. The predicted SARS-CoV-2 binders differed substantially from training sequences, demonstrating generalization beyond sequence memorization. Together, we establish that heavy chain antibody sequences encode sufficient information for PLMs to infer specificity, offering a scalable framework for antibody discovery with broad applications.
]]></description>
<dc:creator>Paco, K.</dc:creator>
<dc:creator>Mendivil, M. P.</dc:creator>
<dc:creator>Zhang, Z.</dc:creator>
<dc:creator>Zebardast, S.</dc:creator>
<dc:creator>Davila, C.</dc:creator>
<dc:creator>Mooney, R. M.</dc:creator>
<dc:creator>Olatoyinbo, P.</dc:creator>
<dc:creator>Yang, T.</dc:creator>
<dc:creator>Bassi, S.</dc:creator>
<dc:creator>Gonzales, V.</dc:creator>
<dc:creator>Chen, E.</dc:creator>
<dc:creator>Ashraf, F. B.</dc:creator>
<dc:creator>Roman, I. C.</dc:creator>
<dc:creator>Felix, J. R.</dc:creator>
<dc:creator>Alam, R. M.</dc:creator>
<dc:creator>Lay, J. A.</dc:creator>
<dc:creator>Johal, M. S.</dc:creator>
<dc:creator>Le Roch, K. G.</dc:creator>
<dc:creator>Tolstorukov, I.</dc:creator>
<dc:creator>Hernandez, J. B.</dc:creator>
<dc:creator>da Silva, F. L. B.</dc:creator>
<dc:creator>Lonardi, S.</dc:creator>
<dc:creator>Sazinsky, M. H.</dc:creator>
<dc:creator>Ray, A.</dc:creator>
<dc:date>2025-10-31</dc:date>
<dc:identifier>doi:10.1101/2025.10.30.685465</dc:identifier>
<dc:title><![CDATA[Fine-tuned Protein Language Model Identifies Antigen-specific B Cell Receptors from Immune Repertoires]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-10-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.02.686144v1?rss=1">
<title>
<![CDATA[
How tp1, an indirect wing steering muscle, stabilizes Drosophila's flight 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.02.686144v1?rss=1</link>
<description><![CDATA[
Flapping flight is inherently unstable, requiring Drosophila to fine-tune their wing motions on a milliseconds timescale. Pioneering studies have shown that the direct steering muscles, which attach to the wing hinge, are important for generating these rapid flight reflexes. Recent connectome data, however, reveal that indirect steering muscles or tension muscles, which alter the mechanics of the thorax, receive some of the same synaptic inputs from the sensory apparatus as the direct steering muscles. This discovery suggests that the indirect steering muscles may also be important for flight control. Here, we show that the indirect tergopleural muscles indeed contribute substantially to stabilization, particularly for large pitch perturbations. We find that for small perturbations (less than 1000 deg/s), flies modulate their wing stroke amplitude to generate lift-based corrective torques, a strategy that has been previously documented. For larger perturbations, however, we observe that Drosophila engage an additional wing degree of freedom--the wing pitch angle--to leverage additional lift and drag forces during the corrective maneuver. Quasi-steady aerodynamic simulations reveal that this strategy minimizes power consumption, anaolgous to how some mammals (including humans) adjust their steady-state gaits in a near energy-optimal manner. Using optogenetics and a control theory framework we demonstrate that the tergopleural muscle is activated by a proportional gain component of a nonlinear PI controller responsible for determining the wing pitch angle during large perturbations. A simplified torsional-spring model for the wing hinge captures the changes in the wing pitch dynamics observed during correction maneuvers by using the tergopleural muscle to adjust the rest angle of the wing. These findings provide a striking example of reflex strategy selection in time-critical behaviors and underscores the vital role of indirect steering muscles in flight stabilization.
]]></description>
<dc:creator>Teoh, H. K.</dc:creator>
<dc:creator>Biswas, D.</dc:creator>
<dc:creator>Leung, A.</dc:creator>
<dc:creator>Ludlow, B. K.</dc:creator>
<dc:creator>Whitehead, S. C.</dc:creator>
<dc:creator>Ehrhard, E.</dc:creator>
<dc:creator>Dickinson, M. H.</dc:creator>
<dc:creator>Beatus, T.</dc:creator>
<dc:creator>Cowan, N.</dc:creator>
<dc:creator>Cohen, I.</dc:creator>
<dc:date>2025-11-04</dc:date>
<dc:identifier>doi:10.1101/2025.11.02.686144</dc:identifier>
<dc:title><![CDATA[How tp1, an indirect wing steering muscle, stabilizes Drosophila's flight]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.05.686753v1?rss=1">
<title>
<![CDATA[
Nitric oxide tunes secreted metabolite bioactivity 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.05.686753v1?rss=1</link>
<description><![CDATA[
The radical nitric oxide ({middle dot}NO) is short-lived but has imprinted itself on many aspects of physiology and disease. {middle dot}NOs rapid production and consumption, coupled with its intrinsic reactivity, drive its biological importance; thus, defining mechanisms and targets of {middle dot}NO reactivity is necessary to assess its fate and impact. Cellular small molecules are a major class of {middle dot}NO-reactive targets, possessing a variety of molecular functionalities that can react with {middle dot}NO. Yet the capacity for secreted small molecules to react with {middle dot}NO, as well as the biological consequences of such reactivity, have received little attention. Here, we explore the reactivity of {middle dot}NO with phenazine metabolites, microbially-derived secreted small molecules that possess antibiotic properties and can modulate their microenvironment. Using Pseudomonas aeruginosa as a model phenazine producer, we find that {middle dot}NO reacts with specific phenazines to yield stable, chemically-distinct products. These chemical transformations significantly attenuate phenazine antibiotic properties, including against the phenazine nonproducer Staphylococcus aureus, a competitor with P. aeruginosa for niches in the context of infection. By contrast, P. aeruginosa experiences rapid loss in viability when phenazines and {middle dot}NO react. This toxicity occurs even in the presence of S. aureus, which displays resistance to nitrosylated phenazines, implicating a specific toxicity dependent on the formation of the phenazine-NO adduct. These findings highlight the capacity of {middle dot}NO to transform metabolite activity and suggest that {middle dot}NO can tune microbial interactions in complex environments by a mechanism of action hitherto unappreciated.
]]></description>
<dc:creator>Lonergan, Z. R.</dc:creator>
<dc:creator>Weisflog, S. L.</dc:creator>
<dc:creator>Scurria, M.</dc:creator>
<dc:creator>Li, J.</dc:creator>
<dc:creator>Thalhammer, K.</dc:creator>
<dc:creator>Gutierrez, O.</dc:creator>
<dc:creator>Conway, S. J.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2025-11-05</dc:date>
<dc:identifier>doi:10.1101/2025.11.05.686753</dc:identifier>
<dc:title><![CDATA[Nitric oxide tunes secreted metabolite bioactivity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.06.686991v1?rss=1">
<title>
<![CDATA[
Electron Cryo-Tomography Reveals the Caulobacter vibrioidesTight Adherence Pilus Architecture 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.06.686991v1?rss=1</link>
<description><![CDATA[
The type IV filament superfamily is a widespread group of molecular machines involved in natural transformation, motility, adhesion, nutrient uptake, and secretion of a wide spectrum of protein substrates. The gram-negative bacterium Caulobacter vibrioides expresses the tight adherence (Tad) pilus, a type IV machine involved in surface colonization. Here we investigated the proteins involved in Tad pilus production by {Phi}CbK resistance screening and the order of machine assembly and its polar remnant by fluorescence tagging. Using electron cryo-tomography and subtomogram averaging of wild-type and mutant strains, we resolved the Tad pilus machine architecture and built an integrative model of its structure. The resulting model suggests the individual roles of multiple Tad proteins. Together the data also reveals the Tad pilus machines assembly order.
]]></description>
<dc:creator>Maggi, S.</dc:creator>
<dc:creator>Rosenzweig, R.</dc:creator>
<dc:creator>Panis, G.</dc:creator>
<dc:creator>Viollier, P. H.</dc:creator>
<dc:creator>Jensen, G. J.</dc:creator>
<dc:date>2025-11-07</dc:date>
<dc:identifier>doi:10.1101/2025.11.06.686991</dc:identifier>
<dc:title><![CDATA[Electron Cryo-Tomography Reveals the Caulobacter vibrioidesTight Adherence Pilus Architecture]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.07.687244v1?rss=1">
<title>
<![CDATA[
Uncovering the molecular basis of kinase activity and substrate recognition with phospho-PCA 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.07.687244v1?rss=1</link>
<description><![CDATA[
Protein kinases relay information to various cellular processes, and their dysregulation underlies numerous human diseases. Despite their importance, our understanding of how kinase domains and their variants impact protein stability, catalytic activity, and substrate recognition is incomplete. In this work, we develop the phosphorylation protein complementation assay (phospho-PCA), which enables quantitative measurements of kinase-substrate interactions by coupling them to the growth of bud-ding yeast, thereby enabling deep mutational scanning of kinase domains. When combined with deep mutational scans targeting folding stability and Bayesian modeling, phospho-PCA can disentangle the relative impact of mutations on kinase domain stability, catalytic activity, and substrate specificity. We demonstrate the accuracy and breadth of phospho-PCA, showing its applicability to both tyrosine and serine/threonine kinase domains. We then apply our method to three closely related protein kinases with distinct substrate preferences, evaluating over 15,000 kinase variants against a panel of three substrates for both catalytic activity and substrate specificity. The resulting dataset constitutes the largest and most detailed variant-to-function map assembled for this enzyme family to date, revealing numerous mutations that alter kinase activity and substrate specificity. Physics-based modeling reveals how these mutations operate through diverse mechanisms, including long-range allosteric communication, to alter both activity and substrate specificity. Given its scalability, we believe phospho-PCA can measure the functional impact of variants across the entire human kinome.
]]></description>
<dc:creator>Yu, C.</dc:creator>
<dc:creator>Pao, E.</dc:creator>
<dc:creator>Van Valen, D. A.</dc:creator>
<dc:date>2025-11-07</dc:date>
<dc:identifier>doi:10.1101/2025.11.07.687244</dc:identifier>
<dc:title><![CDATA[Uncovering the molecular basis of kinase activity and substrate recognition with phospho-PCA]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.06.687049v1?rss=1">
<title>
<![CDATA[
Parkinsons disease modeling in regenerative spiny mice (Acomys dimidiatus) captures key disease-relevant behavioral, histological, and molecular signatures 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.06.687049v1?rss=1</link>
<description><![CDATA[
Parkinsons disease (PD) is a multifactorial neurodegenerative disorder that has been modeled extensively in animals, primarily rodents, but also in non-human primates and non-mammalian organisms. However, no single animal model fully recapitulates the hallmarks of PD pathology. Here, we extend this work by modeling PD for the first time in the spiny mouse (Acomys dimidiatus), a mammal notable for its robust regeneration of multiple tissues. We show that the nigrostriatal pathway of A. dimidiatus is vulnerable to both acute 6-hydroxydopamine (6-OHDA) toxicity and chronic -synuclein (Syn) preformed fibril-induced aggregation. Mouse Syn PFFs produced widespread pS129-positive Syn inclusions across multiple brain regions, mirroring a key pathological hallmark of PD. Compared to C57BL/6J mice, A. dimidiatus exhibited more pronounced behavioral impairments, greater nigrostriatal degeneration, and higher pS129-Syn inclusion burden within substantia nigra pars compacta (SNpc) neurons. To probe the molecular underpinnings behind the vulnerability, we performed single-cell spatial proteomics, which revealed extensive proteomic alterations in dopaminergic neurons associated with Syn aggregation. Multiple proteins were dysregulated in A. dimidiatus, including those involved in proteasomal function, mitochondrial pathways, and oxidative stress regulation, which are processes commonly implicated in PD. Notably, proteomic analysis identified heightened astrocytic activation in the SNpc, which we validated histologically, suggesting a distinct glial response compared to mice. Together, these findings expand our understanding of PD-relevant pathophysiology across species and establish A. dimidiatus as a model for studying mechanisms of neurodegeneration.
]]></description>
<dc:creator>Dutta, S.</dc:creator>
<dc:creator>Pang, M.</dc:creator>
<dc:creator>Donahue, R. R.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Seifert, A. W.</dc:creator>
<dc:creator>Gradinaru, V.</dc:creator>
<dc:date>2025-11-08</dc:date>
<dc:identifier>doi:10.1101/2025.11.06.687049</dc:identifier>
<dc:title><![CDATA[Parkinsons disease modeling in regenerative spiny mice (Acomys dimidiatus) captures key disease-relevant behavioral, histological, and molecular signatures]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.10.687245v1?rss=1">
<title>
<![CDATA[
Hierarchical and Context-Dependent Encoding of Actions in Human Posterior Parietal and Motor Cortex 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.10.687245v1?rss=1</link>
<description><![CDATA[
Action understanding requires internal models that link vision to motor goals. In monkeys, mirror neurons demonstrate motor resonance during observation, but single-unit evidence in humans is limited, leaving open whether such representations rely solely on motor resonance. We recorded neural activity from motor cortex (MC) and superior parietal lobule (SPL) in two tetraplegic participants implanted with Utah arrays while they intended or observed hand actions. MC strongly encoded intention but showed only weak, feature-specific overlap during observation, evident primarily at the population level. SPL, in contrast, supported shared models across intended movement and observation formats at both single-unit and population levels. In variants with incongruent instructed and observed actions, SPL encoded observed actions only when behaviorally relevant, whereas MC remained intention-dominant. Our results identify a context-dependent gating mechanism in SPL and suggest a hierarchical organization in which MC maintains intention-specific codes while SPL flexibly links observed input with internal goals to support action understanding.
]]></description>
<dc:creator>Bougou, V.</dc:creator>
<dc:creator>Gamez, J.</dc:creator>
<dc:creator>Rosario, E. R.</dc:creator>
<dc:creator>Liu, C.</dc:creator>
<dc:creator>Pejsa, K.</dc:creator>
<dc:creator>Bari, A.</dc:creator>
<dc:creator>Andersen, R. A.</dc:creator>
<dc:date>2025-11-11</dc:date>
<dc:identifier>doi:10.1101/2025.11.10.687245</dc:identifier>
<dc:title><![CDATA[Hierarchical and Context-Dependent Encoding of Actions in Human Posterior Parietal and Motor Cortex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.11.687776v1?rss=1">
<title>
<![CDATA[
Phosphorus stress and spatial confinement lower the threshold for quorum-sensing activation of redox-active metabolite production in Pseudomonas synxantha 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.11.687776v1?rss=1</link>
<description><![CDATA[
Bacteria often coordinate collective behaviors such as biofilm formation and secondary metabolite production through quorum sensing (QS), a regulatory system traditionally linked to high cell density. However, in environments like soil, where microbial populations are spatially fragmented, sparse, nutrient-limited, and subject to mass transport, the mechanisms that enable QS-dependent processes remain incompletely understood. Here, we investigate the regulation of a secreted redox-active metabolite, phenazine-1-carboxylic acid (PCA), in Pseudomonas synxantha 2-79, a model rhizobacterium, under phosphorus (P) limitation, a persistent stress in many soils. Using a combination of microscopy and molecular genetic approaches, we show that P limitation sensitizes the QS activation threshold by an order of magnitude, enabling phenazine induction at relatively low population densities in comparison to P replete conditions. This induction is abolished in QS-deficient mutants and restored by the addition of exogenous acyl-homoserine lactone (AHL), demonstrating that quorum sensing remains essential but its threshold becomes environmentally tuned. Under P limitation, spatial confinement and pore saturation levels further shape the timing and location of induction, illustrating how physical structure and nutrient stress can modulate bacterial activities. Moreover, phosphorus stress confers both collaborative and competitive advantages, enabling P. synxantha to undergo low-cell density AHL cross-talk between related Pseudomonas spp. and to suppress other rhizobacteria. Lastly, on plant roots, PCA genes are more predominantly induced under P limitation. These findings illustrate how the nutrient status of an environment can modulate the onset of quorum sensing, enabling quorum-regulated behaviors to activate at lower thresholds.
]]></description>
<dc:creator>Alcade, R. E.</dc:creator>
<dc:creator>Jeckel, H.</dc:creator>
<dc:creator>Zhang, O.</dc:creator>
<dc:creator>Avila, R. L.</dc:creator>
<dc:creator>Dalleska, N.</dc:creator>
<dc:creator>Mavrodi, D.</dc:creator>
<dc:creator>Yang, C.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2025-11-11</dc:date>
<dc:identifier>doi:10.1101/2025.11.11.687776</dc:identifier>
<dc:title><![CDATA[Phosphorus stress and spatial confinement lower the threshold for quorum-sensing activation of redox-active metabolite production in Pseudomonas synxantha]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.11.685779v1?rss=1">
<title>
<![CDATA[
SHORT DISORDERED PEPTIDES ARE SUFFICIENT TO CONVERT PROTEINS INTO MECHANOSENSORS THAT RESPOND TO PHYSIOLOGICAL CELLULAR FORCES 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.11.685779v1?rss=1</link>
<description><![CDATA[
Mechanical forces regulate many biological processes and a handful of mechanosensor domains have been identified in proteins that respond to cellular forces. The Notch signaling pathway, a key regulator of cell communication processes ranging from animal development to cancer, is activated by mechanical forces generated by cell-cell interactions. The mechanosensing element of Notch is thought to be a 300 amino acid extracellular domain called negative regulatory region (NRR). Ligand binding exerts mechanical forces that are believed to partially unfold NRR, rendering it susceptible to cleavage by extracellular metalloproteases that leads to activation of signaling. However, some engineered notch-like receptors lacking the NRR can be activated upon ligand binding, although the mechanisms underlying this activation are not known. Here we observe that Notch molecules without the NRR, but with a 12 amino acid sequence present in the extracellular juxta-transmembrane domain (eJTMD) are also cleaved and activated upon interaction with their ligands in cultured cells and in transgenic animals. Furthermore, the [~]12 aa eJTMD from notch genes from other species (chicken, xenopus, zebrafish and Drosophila), from other unrelated transmembrane proteins (erbB4, N-CAM, and E-Cadherin), or multiple artificial sequences of [~]12 amino acids without any apparent structure or specific sequence can also convert proteins into ligand-dependent mechanosensors. These results indicate that short, disordered amino acid sequences that are commonly found in many proteins are capable of imparting mechanosensing capabilities into proteins, suggesting that mechanical force may regulate many more cellular processes than previously suspected.
]]></description>
<dc:creator>Callejas Marin, A.</dc:creator>
<dc:creator>Gonzalez, W.</dc:creator>
<dc:creator>Pleiner, T.</dc:creator>
<dc:creator>De la Cruz, A.</dc:creator>
<dc:creator>Pandey, A.</dc:creator>
<dc:creator>Sanchez Guardado, L.</dc:creator>
<dc:creator>Jafar-Nejad, H.</dc:creator>
<dc:creator>Voorhees, R.</dc:creator>
<dc:creator>Lois, C.</dc:creator>
<dc:date>2025-11-12</dc:date>
<dc:identifier>doi:10.1101/2025.11.11.685779</dc:identifier>
<dc:title><![CDATA[SHORT DISORDERED PEPTIDES ARE SUFFICIENT TO CONVERT PROTEINS INTO MECHANOSENSORS THAT RESPOND TO PHYSIOLOGICAL CELLULAR FORCES]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.12.687706v1?rss=1">
<title>
<![CDATA[
Elucidating Neurodevelopmental Trajectories in Cancer with Topic Modeling: Revealing Persistent External Granule Layer Lineages in Medulloblastoma 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.12.687706v1?rss=1</link>
<description><![CDATA[
The cerebellar rhombic lip generates cerebellar progenitors and neurons that ultimately differentiate to comprise over half of all neurons in the adult human brain. Standard clustering approaches often fragment or miss rhombic lip progenitor populations entirely due to their transient nature, small size, and rapid state transitions, leaving fundamental questions unanswered about normal cerebellar development and how such processes may be hijacked in pediatric brain cancer. Medulloblastoma, the most common malignant pediatric brain tumor, affects approximately 500 children annually in the United States with overall survival rates varying dramatically by subgroup. Sonic hedgehog (SHH) medulloblastoma, comprising 25-30% of cases, arises from rhombic lip-derived granule neuron precursors (GNP) within the external granule layer (EGL) and has particularly poor outcomes in several subtypes (5-year survival [~]41%). Using our topic modeling framework on over one million fetal cerebellar nuclei, we identify proliferative rhombic lip and EGL states that bifurcate into distinct glial and neuronal lineages through intermediate progenitors and capture a portion of the developmental spectrum form outer EGL (oEGL) proliferation through inner EGL (iEGL) differentiation. These developmental signatures (topics) persist in medulloblastoma, validating GNP origins of SHH tumors and revealing age-specific molecular programs that correspond to distinct stages of EGL development within SHH subtypes. Our transferable framework enables systematic comparison of developmental and disease states across technologies without data integration, solving a fundamental challenge as genomic atlases expand.
]]></description>
<dc:creator>Rajendran, A.</dc:creator>
<dc:creator>Haldipur, P.</dc:creator>
<dc:creator>Arora, S.</dc:creator>
<dc:creator>Grama, K.</dc:creator>
<dc:creator>Subramanian, S. S.</dc:creator>
<dc:creator>Galan, L. M.</dc:creator>
<dc:creator>Johnson, D.</dc:creator>
<dc:creator>Aldinger, K. A.</dc:creator>
<dc:creator>Shendure, J.</dc:creator>
<dc:creator>Millen, K. J.</dc:creator>
<dc:creator>Gennari, J. H.</dc:creator>
<dc:creator>Pattwell, S. S.</dc:creator>
<dc:date>2025-11-13</dc:date>
<dc:identifier>doi:10.1101/2025.11.12.687706</dc:identifier>
<dc:title><![CDATA[Elucidating Neurodevelopmental Trajectories in Cancer with Topic Modeling: Revealing Persistent External Granule Layer Lineages in Medulloblastoma]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.12.688092v1?rss=1">
<title>
<![CDATA[
Proteome-wide identification of metamorphic protein candidates using mass spectrometry 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.12.688092v1?rss=1</link>
<description><![CDATA[
How protein folds remodel at low temperature remains poorly mapped at the proteome scale. We combine brief, temperature-controlled proteolysis with LC-MS/MS to chart cold-dependent conformational changes in Escherichia coli lysate. Methodological validation with the metamorphic protein Sa1V90T--whose /{beta}-plait and 3 states interchange between 30 {degrees}C and 5 {degrees}C--showed that a high-protease, short-digestion regime detects temperature-dependent exposure at four peptides, whereas the temperature-insensitive variant Sa1V90TV52D is largely unchanged. Applied to lysate, the workflow identifies >750 proteolytic sites across >250 abundant proteins (>10% of the identified proteome) whose local susceptibility shifts as temperature decreases from 35 {degrees}C to 5 {degrees}C, including five Sa1V90T peptides recapitulating purified-protein behavior. A site-level scoring model yields 338 destabilized peptides (177 proteins) and 426 stabilized peptides (138 proteins). Cold stabilization prominently marks translation machinery (>15 ribosomal proteins), while cooling also exposes regions in chaperones and cell-division factors. Sequence analysis links temperature sensitivity to charge-enriched composition, consistent with thermodynamic expectations. These data provide a proteome-wide view of cold-sensitive folding, implicate translation and cytokinetic systems in low-temperature remodeling, and illuminate a new strategy for identifying metamorphic proteins on an unprecedented scale.
]]></description>
<dc:creator>Quan, B.</dc:creator>
<dc:creator>Qiu, Y.</dc:creator>
<dc:creator>Carillo, K.</dc:creator>
<dc:creator>Liwang, A.</dc:creator>
<dc:creator>Orban, J.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:date>2025-11-13</dc:date>
<dc:identifier>doi:10.1101/2025.11.12.688092</dc:identifier>
<dc:title><![CDATA[Proteome-wide identification of metamorphic protein candidates using mass spectrometry]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.14.688548v1?rss=1">
<title>
<![CDATA[
Joint Biophysical Modeling of Paired Single-Cell RNA and Protein Measurements 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.14.688548v1?rss=1</link>
<description><![CDATA[
Surface protein measurements can supplement gene expression information from single-cell RNA sequencing to provide a more complete assessment of cell identity and function. Recently developed multiomic assays facilitate such measurements, and can, in principle, be utilized to understand the dynamics of transcription and translation. We develop a framework for biophysical modeling of transcription jointly with translation from single-cell data, along with a suitable technical noise model for sequencing data. We demonstrate its efficacy using simulations, and illustrate how it can be useful in practice with 10x multiomic data. Our proof-of-principle highlights the potential for jointly modeling transcription and translation as data quality and measurement accuracy improves.
]]></description>
<dc:creator>Felce, C.</dc:creator>
<dc:creator>Fang, M.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2025-11-15</dc:date>
<dc:identifier>doi:10.1101/2025.11.14.688548</dc:identifier>
<dc:title><![CDATA[Joint Biophysical Modeling of Paired Single-Cell RNA and Protein Measurements]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-15</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.14.688340v1?rss=1">
<title>
<![CDATA[
Quantitative profiling of whole-brain connectomes at single-axon resolution using deep learning and high-resolution light sheet microscopy 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.14.688340v1?rss=1</link>
<description><![CDATA[
Revealing how individual axons create a brain-wide connectome would be indispensable for understanding brain function and behavior, yet remains technically challenging. We introduce MAPL3, an end-to-end pipeline that integrates self-supervised learning with an innovative deep architecture to capture local and global brain-wide axonal projections. MAPL3 enables subject- and population-level quantitative laminar analysis, generalizes across experiments, and outperforms state-of-the-art methods. We showcase its ability to map the circuitry of the orbitofrontal cortex from single axons to whole-brain projectome.
]]></description>
<dc:creator>Attarpour, A.</dc:creator>
<dc:creator>Raffiee, M.</dc:creator>
<dc:creator>Xu, T.</dc:creator>
<dc:creator>Osmann, J.</dc:creator>
<dc:creator>Patel, S.</dc:creator>
<dc:creator>Yu, F.</dc:creator>
<dc:creator>Au, B.</dc:creator>
<dc:creator>Clappison, A.</dc:creator>
<dc:creator>Biparva, M.</dc:creator>
<dc:creator>Zhu, R.</dc:creator>
<dc:creator>Crow, A.</dc:creator>
<dc:creator>Eshaghi Gharagoz, B.</dc:creator>
<dc:creator>Rozak, M. W.</dc:creator>
<dc:creator>Aubert, I.</dc:creator>
<dc:creator>McLaurin, J.</dc:creator>
<dc:creator>Deisseroth, K.</dc:creator>
<dc:creator>Stefanovic, B.</dc:creator>
<dc:creator>Goubran, M.</dc:creator>
<dc:date>2025-11-16</dc:date>
<dc:identifier>doi:10.1101/2025.11.14.688340</dc:identifier>
<dc:title><![CDATA[Quantitative profiling of whole-brain connectomes at single-axon resolution using deep learning and high-resolution light sheet microscopy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.18.689078v1?rss=1">
<title>
<![CDATA[
Deep Learning-Augmented Stimulated Raman Imaging for Cell-Type-Specific Metabolic Profiling in Live Neuronal Co-Cultures 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.18.689078v1?rss=1</link>
<description><![CDATA[
Neuronal metabolism is fundamental to brain functions and diseases, yet its spatial and temporal dynamics and interactions remain poorly understood. Here, we introduce a tandem deep-learning approach integrated with bioorthogonal chemical imaging using stimulated Raman scattering (SRS) microscopy. This method achieves high-speed and quantitative metabolic profiling in live neuronal co-cultures. Our deep-learning framework consists of a recurrent convolutional neural network (RCNN) that enables high-resolution 3D imaging with minimal photodamage and a U-Net segmentation model for cell-type-specific metabolic analysis. Using deuterium-labeled metabolites, we demonstrate the ability to trace lipid, protein, glucose, and D2O metabolism in neurons, astrocytes, and oligodendrocytes under physiological and pathological conditions, including NMDA receptor activation, proteasome inhibition, and Huntingtons disease. Our findings reveal distinct metabolic adaptations among neuronal cell types and underscore the importance of non-invasive metabolic profiling for understanding neuronal interactions and disease mechanisms. This platform significantly advances live-cell dynamic imaging with broad applications in neuroscience, disease modeling, and therapeutic screening.
]]></description>
<dc:creator>Lin, L.-E.</dc:creator>
<dc:creator>Bi, X.</dc:creator>
<dc:creator>Colazo, A.</dc:creator>
<dc:creator>Wang, H.</dc:creator>
<dc:creator>Wei, L.</dc:creator>
<dc:date>2025-11-18</dc:date>
<dc:identifier>doi:10.1101/2025.11.18.689078</dc:identifier>
<dc:title><![CDATA[Deep Learning-Augmented Stimulated Raman Imaging for Cell-Type-Specific Metabolic Profiling in Live Neuronal Co-Cultures]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.20.688920v1?rss=1">
<title>
<![CDATA[
The LAST mile: Evaluating genetic biocontrol as a supplemental tool for eradicating invasive rodents on islands 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.20.688920v1?rss=1</link>
<description><![CDATA[
Invasive rodents cause severe ecosystem degradation on islands and can be challenging to eradicate. Current best-practices rely heavily on the application of toxic oral baits and have led to successful eradications and remarkable recoveries of native flora and fauna. Yet this single method is not universally applicable. Reliance on a single method limits further eradication success in situations where toxicants cannot be used or remnant populations persist after application. Genetic biocontrol offers a suite of new solutions to potentially improve outcomes in the critical "last mile" of eradication. These approaches involve the release of genetically modified individuals of the target species to reduce population fitness over time. These include self-limiting approaches which require multiple releases and self-sustaining mechanisms (i.e., select gene-drive systems) which could theoretically collapse populations after a single release. While gene drive systems have received significant attention, their development in vertebrates remains technically challenging, and their ecological and regulatory implications are still in active debate. In contrast, some non-drive genetic biocontrol approaches, such as Y-linked editors, fsRIDL, and Gravid Lethal, offer self-limiting alternatives that may be more immediately deployable. These approaches could be used to supplement toxicant-based methods and may also have reduced environmental risks and regulatory barriers. To evaluate the potential of these tools, we developed an individual-based model simulating the eradication of house mice (Mus musculus) on a 125ha island with an initial population of 11,000 individuals. We tested various combinations of genetic biocontrol release and effort strategies to understand tradeoffs between required effort and uncertainty for achieving successful eradication. Under certain effort strategies, we found that the Gravid Lethal approach performed the best, achieving eradication in less than 2.3 years with intensive release effort and monitoring. Our findings suggest that integrating non-drive genetic biocontrol into adaptive management frameworks could enhance the effectiveness and feasibility of rodent eradication programs. These tools are not replacements for toxicants but may serve as critical supplements--particularly in the "last mile" of eradication. Further stakeholder engagement is needed to assess the ecological, ethical, and logistical dimensions of deploying these technologies in real-world settings.
]]></description>
<dc:creator>Birand, A.</dc:creator>
<dc:creator>Hay, B.</dc:creator>
<dc:creator>Combs, M.</dc:creator>
<dc:creator>Gierus, L.</dc:creator>
<dc:creator>Horak, K. E.</dc:creator>
<dc:creator>Oh, K. P.</dc:creator>
<dc:creator>Robertson, L. J.</dc:creator>
<dc:creator>Thomas, P.</dc:creator>
<dc:creator>Velasquez-Escobar, A. M.</dc:creator>
<dc:creator>Will, D. J.</dc:creator>
<dc:creator>Maselko, M.</dc:creator>
<dc:creator>Piaggio, A. J.</dc:creator>
<dc:date>2025-11-21</dc:date>
<dc:identifier>doi:10.1101/2025.11.20.688920</dc:identifier>
<dc:title><![CDATA[The LAST mile: Evaluating genetic biocontrol as a supplemental tool for eradicating invasive rodents on islands]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.21.689845v1?rss=1">
<title>
<![CDATA[
Determining gene specificity from multivariate single-cell RNA sequencing data 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.21.689845v1?rss=1</link>
<description><![CDATA[
An important application of single-cell genomics experiments is to identify genes specific to biological categories or experimental conditions. Although numerous approaches have been proposed to identify such genes, we consider an axiomatic approach based on defining properties that a specificity measure should have. This leads us to develop ember (Entropy Metrics for Biological ExploRation), which we show is the only method satisfying four key desired properties for a specificity measure. Applying ember to eight tissues from eight founder mouse strains, we find that gene specificity is often unintuitive: canonical markers can be supplanted, housekeeping genes are context-dependent, and mouse strain can drive unexpected cell type switching. Unsupervised learning on entropy metrics uncovers shared genes specialized to male gonads and kidney, as well as genes specific to non-consecutive developmental stages in the kidney. To facilitate further exploration of gene specificity in mice, we have also developed a comprehensive specificity database, along with a web interface and API. Extending ember to a human PBMC dataset collected from 255 diverse individuals, we find that variation in PBMCs is largely localized to classical monocytes. We also find genes with unique specificity by sex, age and ancestral background. Together, these applications establish ember as a powerful tool and provide a roadmap for elucidating the impact of human genetic variation using the murine model.
]]></description>
<dc:creator>Swarna, N. P.</dc:creator>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Rebboah, E.</dc:creator>
<dc:creator>Gordon, M. G.</dc:creator>
<dc:creator>Kathail, P.</dc:creator>
<dc:creator>Li, T.</dc:creator>
<dc:creator>Alvarez, M.</dc:creator>
<dc:creator>Ye, C. J.</dc:creator>
<dc:creator>Wold, B. J.</dc:creator>
<dc:creator>Mortazavi, A.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2025-11-24</dc:date>
<dc:identifier>doi:10.1101/2025.11.21.689845</dc:identifier>
<dc:title><![CDATA[Determining gene specificity from multivariate single-cell RNA sequencing data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.24.690267v1?rss=1">
<title>
<![CDATA[
Biophysical constraints on mRNA decay rates shape macroevolutionary divergence in steady-state abundances 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.24.690267v1?rss=1</link>
<description><![CDATA[
Evolutionary changes to gene expression are understood to be a major driver of phenotypic divergence between species. Researchers have investigated the drivers of this divergence by fitting evolutionary models to multi-species  omic datasets. It is now apparent that steady-state mRNA expression levels show patterns consistent with evolutionary constraints, likely as a consequence of stabilizing selection. However, as all previous work has used bulk RNA measurements, it has been impossible to determine which of the many cellular processes that contribute to steady-state abundances underlie the divergence between species. Here we develop a novel paradigm for addressing this open problem. Using multi-species single-cell expression data and biophysical models, we estimate mRNA transcriptional burst sizes, splicing rates and decay rates across multiple species. We then derive phylogenetic models that describe the divergence of these rates under alternative evolutionary scenarios and fit these to the comparative data. We find evidence for biophysical constraints on the rates of mRNA decay, such that macroevolutionary divergence in expression is primarily a consequence of variation in transcriptional bursting.
]]></description>
<dc:creator>Felce, C.</dc:creator>
<dc:creator>Cope, A. L.</dc:creator>
<dc:creator>Schraiber, J. G.</dc:creator>
<dc:creator>Krishnaswamy, M.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Pennell, M.</dc:creator>
<dc:date>2025-11-24</dc:date>
<dc:identifier>doi:10.1101/2025.11.24.690267</dc:identifier>
<dc:title><![CDATA[Biophysical constraints on mRNA decay rates shape macroevolutionary divergence in steady-state abundances]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.23.690051v1?rss=1">
<title>
<![CDATA[
RAPMS 2.0 Improves Specificity and Throughput for Proteomic Identification of RNA Binding Proteins 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.23.690051v1?rss=1</link>
<description><![CDATA[
RNA-protein complexes are critical factors in development, homeostasis, and disease. RNA proteomics methods are essential for characterizing these complexes but suffer from high levels of background, which hinders identification of ribonucleoprotein (RNP) components. Here, we present RNA Antisense Purification followed by Mass Spectrometry 2.0 (RAP-MS 2.0), an updated version our original RAP-MS protocol with innovations in bead preparation, RNA capture, and peptide purification. RAP-MS 2.0 has lower background than our original protocol, and allows lysate to be reused to capture multiple RNAs. We demonstrate that RAP-MS 2.0 recapitulates known RNPs for 7SL, 7SK, RMRP, U1, U2, U6, U7, and Xist. Additionally, we use RAP-MS 2.0 to identify novel RNA-protein interactions between Xist and TREX components and U1 with FET family transcriptional regulators.
]]></description>
<dc:creator>Honson, D.</dc:creator>
<dc:creator>Deng, W.</dc:creator>
<dc:creator>Blanco, M.</dc:creator>
<dc:creator>Sha, J.</dc:creator>
<dc:creator>Plath, K.</dc:creator>
<dc:creator>Wohlschlegl, J. A.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:creator>Majumdar, D.</dc:creator>
<dc:date>2025-11-25</dc:date>
<dc:identifier>doi:10.1101/2025.11.23.690051</dc:identifier>
<dc:title><![CDATA[RAPMS 2.0 Improves Specificity and Throughput for Proteomic Identification of RNA Binding Proteins]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.24.690254v1?rss=1">
<title>
<![CDATA[
k-spaces: Mixtures of Gaussian latent variable models 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.24.690254v1?rss=1</link>
<description><![CDATA[
Principal component analysis (PCA) and k-means clustering are two seemingly different methods for dimension reduction and clustering, respectively, but can be understood as special cases of inference in a Gaussian latent variable model framework. We leverage this insight to develop a probabilistic framework and methods for simultaneous dimension reduction, clustering, and latent space learning that are efficient and interpretable, and that can replace current ad hoc combinations of PCA and clustering. The algorithm, k-spaces, has broad applicability, which we demonstrate in several distinct genomic settings. In particular, we show how k-spaces can be used to model gene expression in quantitative hybridization chain reaction (qHCR) images, for inference in epigenomics, and for dimension reduction of single-cell RNA-sequencing data.
]]></description>
<dc:creator>Markarian, N.</dc:creator>
<dc:creator>Engelhardt, B. E.</dc:creator>
<dc:creator>Pierce, N. A.</dc:creator>
<dc:creator>Sternberg, P. W.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2025-11-28</dc:date>
<dc:identifier>doi:10.1101/2025.11.24.690254</dc:identifier>
<dc:title><![CDATA[k-spaces: Mixtures of Gaussian latent variable models]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.26.690863v1?rss=1">
<title>
<![CDATA[
Distributed activity in the human posterior putamen distinguishes goal-directed from habitual control in humans 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.26.690863v1?rss=1</link>
<description><![CDATA[
How do some individuals rapidly form habits while others maintain flexible, goal-directed control? Using multivariate fMRI decoding in 199 participants, we show that distributed neural activity patterns in the left posterior putamen during initial learning predict individual behavioral strategy on a subsequent outcome devaluation test. This prediction generalized across two independent cohorts of healthy adults and psychiatric patients with heterogeneous diagnoses and was anatomically specific to the posterior putamen. Critically, predictive neural signatures were present during training, before strategy expression after devaluation, enabling prospective classification of habitual versus goal-directed behavior. These findings demonstrate that stable individual differences in behavioral control are reflected in circumscribed brain activity during learning, highlighting the posterior putamen as a candidate neural marker of habit propensity with potential clinical relevance.
]]></description>
<dc:creator>Johri, A.</dc:creator>
<dc:creator>Kluen, L. M.</dc:creator>
<dc:creator>Gera, R.</dc:creator>
<dc:creator>Man, V.</dc:creator>
<dc:creator>Perez, O. D.</dc:creator>
<dc:creator>Simon, J. P.</dc:creator>
<dc:creator>Ding, W.</dc:creator>
<dc:creator>Fransen, A.</dc:creator>
<dc:creator>Cho, S.</dc:creator>
<dc:creator>Oh, S.</dc:creator>
<dc:creator>Cockburn, J.</dc:creator>
<dc:creator>Feusner, J.</dc:creator>
<dc:creator>Tadayon-Nejad, R.</dc:creator>
<dc:creator>O'Doherty, J.</dc:creator>
<dc:date>2025-11-28</dc:date>
<dc:identifier>doi:10.1101/2025.11.26.690863</dc:identifier>
<dc:title><![CDATA[Distributed activity in the human posterior putamen distinguishes goal-directed from habitual control in humans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.30.691379v1?rss=1">
<title>
<![CDATA[
Nanoscale imaging of native symbiotic animal tissue using amultimodal large volume imaging pipeline for cryo-electrontomography 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.30.691379v1?rss=1</link>
<description><![CDATA[
The field of cryo-EM offers the possibility to gain high-resolution structural information of biomolecules in their native state. Advances in sample thinning of cryo-EM samples allows the study of proteins inside intact cells using tomography, opening the door for  visual proteomics. However, thicker samples such as tissues or entire organisms are still largely unsuitable for cryo-electron tomography (cryo-ET). Therefore, significant efforts are directed toward developing and improving preparation methods to enable cryo-ET of such complex samples. We focused on the binary association between the Hawaiian bobtail squid Euprymna scolopes and the luminous bacteria Vibrio fischeri. The Squid-Vibrio system has long been studied to understand host-symbiont interactions. Our goal is to study the bacterial-host interface using cryo-ET, at a resolution previously unattainable by conventional EM methods. Here, we present a multi-modal preparation and correlative imaging workflow--including cryo- fluorescence microscopy, microCT, freeze-substitution electron tomography (FS-ET), and serial blockface SEM--to localize and prepare specific regions of the dissected symbiotic light organs for cryo-ET. This approach enabled us to directly visualize symbiotic V. fischeri within the internal host crypts at macromolecular resolution, revealing spatial organization, physical contact, and putative exchange interfaces between host and microbe. Our findings provide structural insights into a foundational model of host-microbe symbiosis and demonstrate the feasibility of cryo-ET for investigating intact tissues at the nanoscale.
]]></description>
<dc:creator>Gundlach, K. A.</dc:creator>
<dc:creator>Schiotz, O. H.</dc:creator>
<dc:creator>Ladinsky, M. S.</dc:creator>
<dc:creator>Raimann, C.</dc:creator>
<dc:creator>Rheinberger, M.</dc:creator>
<dc:creator>Beck, F.</dc:creator>
<dc:creator>Guenduez, B.</dc:creator>
<dc:creator>Langelaan, R.</dc:creator>
<dc:creator>Ruecklin, M.</dc:creator>
<dc:creator>Limpens, R. W. A. L.</dc:creator>
<dc:creator>Ruby, E. G.</dc:creator>
<dc:creator>McFall-Ngai, M.</dc:creator>
<dc:creator>Plitzko, J. M.</dc:creator>
<dc:creator>Briegel, A.</dc:creator>
<dc:date>2025-11-30</dc:date>
<dc:identifier>doi:10.1101/2025.11.30.691379</dc:identifier>
<dc:title><![CDATA[Nanoscale imaging of native symbiotic animal tissue using amultimodal large volume imaging pipeline for cryo-electrontomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.28.691177v1?rss=1">
<title>
<![CDATA[
Development of a Recombinant Single-Cycle Influenza Viral Vector as an Intranasal Vaccine against SARS-CoV-2 and SARS-like Betacoronaviruses 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.28.691177v1?rss=1</link>
<description><![CDATA[
The COVID-19 pandemic has demonstrated the detrimental potential of zoonotic coronavirus transmission to human populations. Effective vaccines capable of eliciting immunity to SARS-CoV-2 have been pivotal in mitigating the spread of the virus. In this study, we describe the generation of a non-replicating pseudotyped influenza A virus (S-FLU), where the native haemagglutinin (HA) sequence is replaced with the coding sequence of either a membrane-anchored form (TM) or secretory form (Sec) of the receptor-binding domain (RBD) of the ancestral SARS-CoV-2 Wuhan (S-RBD Wuhan). We showed that both S-RBD-TM and S-RBD-Sec viruses can be generated via reverse genetics and grown to high titre. Intranasal immunisation in mice with S-RBD-TM elicits robust serum binding and neutralisation activity against SARS-CoV-2, superior to S-RBD-Sec. Furthermore, we demonstrate that a heterologous prime-boost immunisation regime in mice with S-RBD-TM Wuhan and S-RBD-TM BM48-31 (a distant Clade 3 SARS-like betacoronavirus (sarbecovirus)) increases antibody breadth against mismatched sarbecoviruses compared to homologous prime-boost with S-RBD-TM Wuhan. These results suggest that S-RBD-TM is a promising intranasal vaccine candidate against SARS-CoV-2 and may offer potential as a broadly protective sarbecovirus vaccine.
]]></description>
<dc:creator>Munro, J.</dc:creator>
<dc:creator>Melnyk, D.</dc:creator>
<dc:creator>Schimanski, L.</dc:creator>
<dc:creator>Afzal, M.</dc:creator>
<dc:creator>Cohen, A. A.</dc:creator>
<dc:creator>Keeffe, J.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>James, W. S.</dc:creator>
<dc:creator>Townsend, A. R.</dc:creator>
<dc:creator>Tan, T. K.</dc:creator>
<dc:date>2025-12-01</dc:date>
<dc:identifier>doi:10.1101/2025.11.28.691177</dc:identifier>
<dc:title><![CDATA[Development of a Recombinant Single-Cycle Influenza Viral Vector as an Intranasal Vaccine against SARS-CoV-2 and SARS-like Betacoronaviruses]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-12-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.1101/2025.11.30.691445v1?rss=1">
<title>
<![CDATA[
Naegleria amoebae seek confinement and crawl persistently through narrow spaces 
]]>
</title>
<link>https://biorxiv.org/content/10.1101/2025.11.30.691445v1?rss=1</link>
<description><![CDATA[
The "brain-eating amoeba" Naegleria fowleri dwells in ponds where it normally feeds on bacteria, but if it enters the brain it can cause a deadly infection. To establish infection, N. fowleri must migrate through different environments--along olfactory axons, through openings in the cribriform plate, and within brain tissue--yet how it does so remains unknown. As a model for N. fowleri migration within these environments, we examine how its non-pathogenic relative, Naegleria gruberi, navigates environments of distinct geometries. We show that Naegleria uses both actin-rich protrusions and membrane blebs to crawl across or between flat surfaces. We also explore how Naegleria interact with narrow channels and find that, unlike Dictyostelium amoebae that we show frequently disengage from channel interfaces, Naegleria amoebae probe channels until they enter. Once inside, Naegleria crawls quickly (>50 m/min) and unidirectionally over long distances (>1 mm) using only bleb-based motility. We also introduced Naegleria to granular hydrogel matrices that mimic pond sediments and found that cells readily enter and migrate through these three-dimensional matrices using both blebs and lamellar protrusions. Although cells in matrices showed lower persistence at short timescales, longer time scales correlate with increased persistence, suggesting Naegleria cells may retain memory of past orientation. We propose that pond life may select for three behaviors that prime Naegleria for pathogenesis: memory-guided motility that would facilitate exploration of sinus cavities, confinement-seeking ("claustrophilia") that would promote entry into narrow passages along olfactory axons, and fast bleb-based migration that would allow rapid transit along axons to the brain.

SIGNIFICANCE STATEMENTThe "brain-eating amoeba" Naegleria fowleri causes a devastating brain infection with a [~]95% fatality rate, yet how these normally harmless pond-dwellers invade the human brain remains mysterious. Using the model species N. gruberi, we show that Naegleria amoebae exhibit three key behaviors: they retain directional memory during exploration, actively enter confined spaces, and crawl rapidly and persistently through narrow channels for millimeter-scale distances. We propose these behaviors are adaptations for hunting bacteria in pond sediments that inadvertently enable pathogenesis--directional memory facilitates sinus exploration, confinement-seeking draws amoebae into spaces between olfactory axons, and persistent channel migration enables rapid transit to the brain.
]]></description>
<dc:creator>Velle, K.</dc:creator>
<dc:creator>Ramaswamy, M.</dc:creator>
<dc:creator>Hokmabad, B. V.</dc:creator>
<dc:creator>Martin-Perez, T.</dc:creator>
<dc:creator>Carrasco, T. T.</dc:creator>
<dc:creator>Callahan, W. S.</dc:creator>
<dc:creator>Kim, H. S.</dc:creator>
<dc:creator>Datta, S. S.</dc:creator>
<dc:creator>Edwards, M.</dc:creator>
<dc:creator>Fritz-Laylin, L.</dc:creator>
<dc:date>2025-12-01</dc:date>
<dc:identifier>doi:10.1101/2025.11.30.691445</dc:identifier>
<dc:title><![CDATA[Naegleria amoebae seek confinement and crawl persistently through narrow spaces]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-12-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2025.11.30.691048v1?rss=1">
<title>
<![CDATA[
Ultrasonic Reporter of Kinase Activity 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2025.11.30.691048v1?rss=1</link>
<description><![CDATA[
Protein kinases are an essential class of enzymes that regulate cellular signaling pathways, with their dysregulation implicated in pathologies such as cancer and neurodegenerative diseases. Despite the existence of high-performance fluorescent biosensors of kinase activity, it remains challenging to study the function and regulation pathways of kinases in opaque tissues due to the limited tissue penetration of light. To address this limitation, we introduce the first ultrasonic reporter of kinase activity (UReKA), designed to detect protein kinase A (PKA) activity by altering the ultrasound scattering of gas vesicles, a unique class of air-filled protein nanostructures. We engineer a gas vesicle shell protein to respond to PKA, demonstrate the functionality of UReKA both in purified protein format and expressed in mammalian cells, and showcase its capacity to monitor PKA signaling in response to pharmacological stimulation or genetic mutation. This work makes it possible to visualize cellular functional activity in opaque media, with broad potential for future applications in cancer biology, cellular development, and drug discovery.
]]></description>
<dc:creator>Yang, J. W.</dc:creator>
<dc:creator>Jin, Z.</dc:creator>
<dc:creator>Wang, T. Y.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2025-12-02</dc:date>
<dc:identifier>doi:10.64898/2025.11.30.691048</dc:identifier>
<dc:title><![CDATA[Ultrasonic Reporter of Kinase Activity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-12-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2025.11.30.691342v1?rss=1">
<title>
<![CDATA[
Cycling of sulfur redox intermediates drives microbial activity in the sulfate-methane transition zone of cold methane seeps 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2025.11.30.691342v1?rss=1</link>
<description><![CDATA[
Microbial sulfate reduction is a cornerstone of marine sediment biogeochemistry, driving carbon remineralization and fueling the anaerobic oxidation of methane (AOM). Yet in zones of high methane flux, sulfate limitations may constrain the sulfate-reducing bacteria (SRB) and anaerobic methanotrophic archaea (ANME) that typically perform AOM. Although often overlooked, sulfur redox intermediates are readily utilized by diverse microorganisms, potentially driving AOM in sulfate-limited zones. To resolve the microbial mechanisms underlying cryptic sulfur cycling in such sediments, Monterey Canyon cold methane seeps were investigated through an integrated geochemical, isotopic, and metatranscriptomic approach. High-resolution electrochemical measurements confirmed intense sulfide production in seep sites, and long-term anoxic incubations were conducted with sediment from the SMTZ amended with elemental sulfur, thiosulfate, or sulfate as the sole sulfur source, with or without methane. Over 650 days, sulfide accumulation was greatest in elemental sulfur treatments, followed by thiosulfate and sulfate; in all cases methane addition enhanced sulfide production. Isotopic measurements showed modest S-isotope fractionation indicating that the large fractionations typical of slow sulfate reduction were muted by additional sulfur transformations. In elemental sulfur treatments, isotopic and geochemical patterns suggested that disproportionation was unlikely. Metatranscriptomes revealed broad expression of sox genes and abundant dsr/apr across treatments, along with thiosulfate-linked phs upregulation. While ANME-2c and SEEP-SRB2 activity increased with methane, transcriptomic and isotopic data together highlighted the roles of Desulfocapsaceae, Desulfobulbaceae, and Sulfurovaceae lineages in mediating sulfur transformations. Taken together, these results demonstrate how cryptic sulfur cycling may sustain microbial communities in sulfate-depleted deep-sea sediments and contribute to AOM.
]]></description>
<dc:creator>Eitel, E. M.</dc:creator>
<dc:creator>Murali, R.</dc:creator>
<dc:creator>Utter, D. R.</dc:creator>
<dc:creator>Wu, F.</dc:creator>
<dc:creator>Lim, S.</dc:creator>
<dc:creator>Connon, S. A.</dc:creator>
<dc:creator>Sessions, A.</dc:creator>
<dc:creator>Orphan, V. J.</dc:creator>
<dc:date>2025-12-02</dc:date>
<dc:identifier>doi:10.64898/2025.11.30.691342</dc:identifier>
<dc:title><![CDATA[Cycling of sulfur redox intermediates drives microbial activity in the sulfate-methane transition zone of cold methane seeps]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-12-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2025.12.04.692398v1?rss=1">
<title>
<![CDATA[
Uniform pre-processing of bacterial single-cell RNA-seq 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2025.12.04.692398v1?rss=1</link>
<description><![CDATA[
Bacteria are highly heterogeneous, even under controlled conditions, making single-cell RNA sequencing (scRNA-seq) essential for studying microbial diversity and symbiosis. Since its first application in 2015, bacterial scRNA-seq has expanded, but different assays depend on distinct, custom, in-house preprocessing making it difficult to analyze data as part of a unified workflow. The kallisto-bustools suite of tools has enabled uniform pre-processing of eukaryotic scRNA-seq while also reducing time and resource demands for pre-processing, but is not optimized for bacterial scRNA-seq. We adapt kallisto-bustools to be suitable for reads generated from operons, as well as for a much shorter gene length distribution, and show that it can efficiently and accurately quantify bacterial scRNA-seq. Our work provides a scalable foundation for uniform pre-processing of microbial single-cell transcriptomics.
]]></description>
<dc:creator>Oakes, C. G.</dc:creator>
<dc:creator>Beilinson, V.</dc:creator>
<dc:creator>McFall-Ngai, M. J.</dc:creator>
<dc:creator>Pachter, L. G.</dc:creator>
<dc:date>2025-12-06</dc:date>
<dc:identifier>doi:10.64898/2025.12.04.692398</dc:identifier>
<dc:title><![CDATA[Uniform pre-processing of bacterial single-cell RNA-seq]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-12-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2025.12.16.694696v1?rss=1">
<title>
<![CDATA[
Structures of bacterial and human phosphoglycosyltransferases bound to a common inhibitor inform selective therapeutics 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2025.12.16.694696v1?rss=1</link>
<description><![CDATA[
Glycoconjugates facilitate myriad biological processes, including cell-cell recognition and immune response, and they are generated by enzymes that transfer glycans. The orthologs MraY and DPAGT1 are dimeric phosphoglycosyltransferases involved in oligosaccharide biosynthesis for either bacterial peptidoglycan or eukaryotic N-linked glycans, respectively. Both enzymes play central regulatory roles, making them attractive targets for antibacterial and anticancer therapies. In our prior studies, a muraymycin A1-derived inhibitor termed APPB (aminouridyl phenoxypiperidinbenzyl butanamide) was developed. It exhibits sub-100 nM IC50 values against both MraY and DPAGT1 and has demonstrated efficacy against DPAGT1-dependent cancers, making it an excellent starting point for next-generation small molecules. To guide inhibitor development, we determined cryo-EM structures of APPB bound to MraY or DPAGT1 at 2.9 [A] resolution using single-particle analysis. The structures reveal that APPB, composed of a nucleoside, a central amide, and a lipid-mimetic, adopts two conformations in each protein, which correlate with local hydrogen-bonding contacts of the central amide carbonyl. Examination of the amide carbonyl environments guides conformer selection for future DPAGT1-targeting anticancer agents. Further, comparisons of APPB-bound geometries and nucleoside interactions inform opportunities for antibacterial agents targeting MraY. Overall, our study provides design principles for MraY- or DPAGT1-specific drugs and motivates the utility of simultaneously characterizing inhibitor-bound orthologs for selective therapeutics.
]]></description>
<dc:creator>Kirsh, J.</dc:creator>
<dc:creator>Mitachi, K.</dc:creator>
<dc:creator>Ochoa, J.</dc:creator>
<dc:creator>Soroush-Pejrimovsky, M.-T.</dc:creator>
<dc:creator>Li, Y. E.</dc:creator>
<dc:creator>Nguyen, V. N.</dc:creator>
<dc:creator>Kurosu, M.</dc:creator>
<dc:creator>Clemons, W.</dc:creator>
<dc:date>2025-12-16</dc:date>
<dc:identifier>doi:10.64898/2025.12.16.694696</dc:identifier>
<dc:title><![CDATA[Structures of bacterial and human phosphoglycosyltransferases bound to a common inhibitor inform selective therapeutics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-12-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2025.12.19.695576v1?rss=1">
<title>
<![CDATA[
Computational array reconstruction for spatial transcriptomics 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2025.12.19.695576v1?rss=1</link>
<description><![CDATA[
Several optics-free spatial transcriptomics assays that make use of diffusion of reads from beads have recently been developed, and provide a proof of principle for high-throughput, untargeted, spatial transcriptomics. These approaches leads to a challenging computational array reconstruction problem. We show that an statistical inference method, which we term accumap, outperforms the current approach which is to run UMAP on the bead count matrix. The accumap method makes use of predicted distances to reconstruct bead positions and can improve the accuracy of reconstruction by a factor of 3 in the diffusible Slide-Tag simulation framework.
]]></description>
<dc:creator>Oakes, C. G.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2025-12-23</dc:date>
<dc:identifier>doi:10.64898/2025.12.19.695576</dc:identifier>
<dc:title><![CDATA[Computational array reconstruction for spatial transcriptomics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-12-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2025.12.24.696433v1?rss=1">
<title>
<![CDATA[
Did you see the sound? A Bayesian Perspective on Crossmodal Perception in Low Vision 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2025.12.24.696433v1?rss=1</link>
<description><![CDATA[
Multisensory integration is often assumed to increase when visual input is degraded, yet it re-mains unclear whether low vision enhances susceptibility to cross-modal illusions or whether such effects depend on local variations in visual reliability. We tested low vision and sighted control participants on the Double Flash Illusion across 24 visual-field locations while sepa-rately measuring flash-detection accuracy. Both groups showed the expected auditory-driven increase in perceived flash numerosity, but only sighted controls reliably experienced the clas-sic "double-flash" percept. Illusion strength did not vary with eccentricity; instead, it was strongly predicted by local flash detection accuracy, indicating that sound-induced percepts depend on the availability of a reliable visual signal. Bayesian Causal Inference modeling revealed substantially weaker and more variable fits for low vision observers, with poorer fits associated with reduced visual sensitivity. Although model parameters did not differ significantly between groups, the similarity in estimated visual noise likely reflects model limitations rather than true equivalence in sensory precision. Together, these findings show that low vision does not globally amplify audiovisual interactions; rather, auditory enhance-ment depends on local visual reliability, and degraded vision leads to weaker alignment with Bayesian-optimal predictions.
]]></description>
<dc:creator>Chan, A. Y. C.</dc:creator>
<dc:creator>Stiles, N. R. B.</dc:creator>
<dc:creator>Levitan, C. A.</dc:creator>
<dc:creator>Tanguay, A. R.</dc:creator>
<dc:creator>Shimojo, S.</dc:creator>
<dc:date>2025-12-26</dc:date>
<dc:identifier>doi:10.64898/2025.12.24.696433</dc:identifier>
<dc:title><![CDATA[Did you see the sound? A Bayesian Perspective on Crossmodal Perception in Low Vision]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-12-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2025.12.28.696421v1?rss=1">
<title>
<![CDATA[
Trainable computation in molecular networks 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2025.12.28.696421v1?rss=1</link>
<description><![CDATA[
Reports of learning in single cells without genetic change span decades yet remain controver-sial, in part because there is no accepted general molecular mechanism for training comparable to gradient-based training or Hebbian learning in neural circuits. Here we identify a minimal set of ingredients sufficient to realize non-genetic learning, drawing inspiration from Boltzmann neural networks. First, dense reversible interaction networks provide an expressive substrate in which modulating the concentrations of a small set of mediator species can reprogram function without altering the underlying interaction parameters. Second, a simple rate-sensitive autoregulatory scheme that adjusts these mediator levels provides a local Hebbian-like training rule that can train the same network for diverse tasks, including Pavlovian conditioning, supervised classification, and generative tuning of bet-hedging ratios to match environmental statistics. We show that this autoregulatory training rule is model free and applies to reversible multimerization networks of arbitrary complexity, so training can compensate for unknown or unmodeled interactions present in vivo. These results suggest design principles for trainable synthetic cellular circuits and indicate how molecular systems could learn statistical features of their environments through experience.
]]></description>
<dc:creator>Trifonova, K.</dc:creator>
<dc:creator>Falk, M. J.</dc:creator>
<dc:creator>Rouches, M.</dc:creator>
<dc:creator>Vaikuntanathan, S.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:creator>Murugan, A.</dc:creator>
<dc:date>2025-12-30</dc:date>
<dc:identifier>doi:10.64898/2025.12.28.696421</dc:identifier>
<dc:title><![CDATA[Trainable computation in molecular networks]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-12-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.01.07.698303v1?rss=1">
<title>
<![CDATA[
A view of bird's eyes -- Pigeons lock their eyes in place during flight 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.01.07.698303v1?rss=1</link>
<description><![CDATA[
Vision in most animals follows a fixate-and-saccade pattern. Birds fixate their viewing direction, then rapidly shift this gaze through head and eye movements. We used a head-mounted eye-tracking system in flying pigeons to relate eye to head movement and map eye position within the head. After take-off, the birds increased pupil size and adopted a fixed and consistent eye position in their head. In different visual environments, eye position returned to within 1{degrees} during flight. When flying, the birds positioned their eyes close to the primary horizontal axes of their vestibular systems. Because visual neurons share a common reference frame with the vestibular system, a consistent flight gaze position may actively align vision with mechanosensation and facilitate perception of self-motion.

One-Sentence SummaryA head-mounted eye-tracking system shows that pigeons adopt a consistent eye-in-head position during free flight
]]></description>
<dc:creator>Ros, I. G.</dc:creator>
<dc:creator>Bhagavatula, P. S.</dc:creator>
<dc:creator>Biewener, A. A.</dc:creator>
<dc:date>2026-01-08</dc:date>
<dc:identifier>doi:10.64898/2026.01.07.698303</dc:identifier>
<dc:title><![CDATA[A view of bird's eyes -- Pigeons lock their eyes in place during flight]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-01-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.01.12.697931v1?rss=1">
<title>
<![CDATA[
Starvation enhances bacterial survival through drying and rewetting at the single cell level 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.01.12.697931v1?rss=1</link>
<description><![CDATA[
Soil bacteria are critical to agricultural productivity and play a central role in several biogeochemical cycles. These organisms frequently experience desiccation, which deprives them of access to both water and nutrients. Desiccation eliminates the aqueous connections between soil pores, removing pathways for nutrient diffusion. Well-studied yet resource intensive water stress responses like osmolyte synthesis may thus be impractical in unsaturated environments. Accordingly, we observed how the rhizobacterium Pseudomonas synxantha 2-79 responds to co-occurring water and nutrient limitation at the single-cell level to understand what role osmolyte synthesis may play in its desiccation response. We constructed a transcriptional reporter to track P. synxanthas osmolyte response and collected extensive morphological and reporter expression data through experiments designed to mimic different rates and extents of soil drying. Only actively growing cells responded to an osmotic shock by synthesizing osmolytes: this response was not observed when we pre-starved bacteria. Soluble nutrient diffusivity in soil is restricted even when there is sufficient water to keep bacterial cells hydrated, so this pre-starved condition reflects gradual drying in which starvation precedes water stress. Despite the lack of osmolyte synthesis, prior starvation enhanced P. synxanthas ability to recover from osmotic stress once water and nutrients were restored. These results suggest that cellular changes associated with the response to starvation that go beyond osmolyte synthesis play an important role in microbial desiccation tolerance.

Significance StatementSoil bacteria play a vital role in agriculture by promoting plant productivity. Despite this, it is unclear how these organisms respond to desiccation, a common stress whose frequency is rising. Desiccation both dehydrates bacterial cells and eliminates the liquid water connections between soil pores that bacteria use to access nutrients. We studied how a model soil bacterium responds to simultaneous starvation and water stress at the single cell level, focusing on whether the bacteria synthesized osmolytes, small molecules that bacteria can accumulate to limit water loss. We found that starvation restricts osmolyte synthesis but enables bacteria to withstand more severe water stress. The starvation that accompanies desiccation may play a protective, rather than an antagonistic, role in microbial desiccation tolerance.
]]></description>
<dc:creator>Kwiecinski, J. V.</dc:creator>
<dc:creator>Squyres, G. R.</dc:creator>
<dc:creator>Or, D.</dc:creator>
<dc:creator>Newman, D. K.</dc:creator>
<dc:date>2026-01-12</dc:date>
<dc:identifier>doi:10.64898/2026.01.12.697931</dc:identifier>
<dc:title><![CDATA[Starvation enhances bacterial survival through drying and rewetting at the single cell level]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-01-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.01.23.701335v1?rss=1">
<title>
<![CDATA[
How the olfactory bulb maintains stable odor manifolds amid adaptation and representational drift 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.01.23.701335v1?rss=1</link>
<description><![CDATA[
Adaptive coding in sensory circuits enables stable perception while accommodating experience-dependent changes. In the olfactory bulb (OB), repeated odor exposure reshapes population activity even without explicit behavioral feedback, but the underlying circuit mechanisms remain unclear. By analyzing longitudinal two-photon calcium imaging datasets from the mouse OB, we identified three concurrent forms of representational change: gain adaptation, similarity-dependent pattern separation or convergence, and a rotation of encoding subspace resulting in the representational drift. Using a computational model of the mitral cell-granule cell circuit, we showed that Hebbian plasticity and structural connectivity constraints are sufficient to reproduce these transformations. Despite global representational drift, the relative geometry of odor response vectors remained stable, preserving a low-dimensional odor manifold. Together, our results reveal how local plasticity and network structure jointly enable both stability and flexibility in early sensory coding.
]]></description>
<dc:creator>Zheng, C. X.</dc:creator>
<dc:creator>Yu, B.</dc:creator>
<dc:creator>Navlakha, S.</dc:creator>
<dc:creator>Koulakov, A.</dc:creator>
<dc:date>2026-01-25</dc:date>
<dc:identifier>doi:10.64898/2026.01.23.701335</dc:identifier>
<dc:title><![CDATA[How the olfactory bulb maintains stable odor manifolds amid adaptation and representational drift]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-01-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.01.25.701606v1?rss=1">
<title>
<![CDATA[
Dynamic regulation of endogenous transcription factor hubs at single-molecule resolution 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.01.25.701606v1?rss=1</link>
<description><![CDATA[
Eukaryotic transcription factors (TFs) form local, high-concentration hubs at specific genomic loci through dynamic, multivalent protein-protein interactions mediated by their low-complexity domains. The hub formation behavior plays an essential role in TFs transcriptional activation activities. Characterizing the dimensions, dynamics, and regulation of TF hubs requires high-resolution imaging of TFs in their native cellular environment, but much of such biophysical characterization remains missing. Here, we combined CRISPR/Cas9-mediated genome editing and advanced quantitative cell imaging, including single-molecule microscopy, to investigate the dynamic behaviors of the endogenous oncogenic fusion TF EWS::FLI1 in Ewing sarcoma cells. We found that endogenous EWS::FLI1 forms dynamic, sub-diffraction-limit hubs with mechanisms of dissolution that prevent the hubs from achieving macroscopic liquid-liquid phase separation. Hub formation is a neomorphic behavior of EWS::FLI1 that is not directly conferred by its parental proteins, EWSR1 and FLI1. We found that during mitosis, EWS::FLI1 hubs dissolve, but EWS::FLI1 molecules continue to dynamically bind and unbind mitotic chromosomes, revealing a role of EWS::FLI1 in mitotic bookmarking. Nascent RNA destabilizes EWS::FLI1 hubs on chromatin, but it does not affect the dimensions of the hubs. Finally, we visualized endogenous EWS::FLI1 hubs upon treatment with various compounds that were previously indicated to affect EWS::FLI1 function. We found that LY2835219 and trabectedin significantly alter the nuclear distribution of endogenous EWS::FLI1, disrupting and mislocalizing EWS::FLI1 hubs, respectively. This finding highlights the therapeutic potential of both compounds for Ewing sarcoma. Together, our results reveal new insights into the assembly and regulation of endogenous EWS::FLI1 hubs at an unprecedented resolution. The methodology developed here will be useful for characterizing the functional hubs of many regular and pathological TFs in the future.
]]></description>
<dc:creator>Yoshida, S. R.</dc:creator>
<dc:creator>Zhong, Y.</dc:creator>
<dc:creator>Kumagai, A.</dc:creator>
<dc:creator>Dunphy, W. G.</dc:creator>
<dc:creator>Chong, S.</dc:creator>
<dc:date>2026-01-27</dc:date>
<dc:identifier>doi:10.64898/2026.01.25.701606</dc:identifier>
<dc:title><![CDATA[Dynamic regulation of endogenous transcription factor hubs at single-molecule resolution]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-01-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.01.26.701395v1?rss=1">
<title>
<![CDATA[
BiomarkerKB: FAIR and Integrated Biomarker Knowledge Connecting Biomolecular and Clinical Data Types 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.01.26.701395v1?rss=1</link>
<description><![CDATA[
Biomarkers are essential tools for disease detection, risk assessment, therapeutic monitoring, and precision medicine. However, biomarker data are dispersed across heterogeneous resources, inconsistently reported in the literature, and rarely standardized for computational use. This fragmentation limits reproducibility, cross-study integration, and the discovery of novel biomarker and disease relationships. We developed BiomarkerKB, a knowledgebase designed to harmonize and integrate biomarker information under a standardized data model. The model follows the FDA-NIH BEST biomarker definition and captures both core fields (biomarker entity, disease/condition, exposure agent) and contextual metadata (specimen, biomarker role, evidence, provenance). Biomarker data and related annotations were either curated from publications or collected from public resources (e.g., OpenTargets, GWAS Catalog, ClinVar, CIViC, OncoMX) and were also contributed by the Common Fund Data Coordinating Centers and the Early Detection Research Network (EDRN). Standardization was achieved using ontologies and reference resources such as Disease Ontology, UBERON, UniProtKB, and HUGO Gene Nomenclature Committee (HGNC) gene symbols. BiomarkerKB data were ingested into a Neo4j-based knowledge graph and integrated with the Common Fund Data Ecosystem (CFDE) Knowledge Graph. The initial release of BiomarkerKB contains over 200,000 biomarker-disease associations spanning genes, proteins, metabolites, glycans, and chemical elements. The knowledge graph comprises more than 300,000 nodes and 1.2 million edges, enabling structured exploration of biomarker relationships within CFDE data as demonstrated through the knowledge graph query-based use cases presented in this study. A publicly accessible web portal (https://biomarkerkb.org) provides keyword search, filtering, data downloads, and access to graph visualization to support both researchers and computational analyses. BiomarkerKB addresses a critical gap in biomarker informatics by providing an integrated, FAIR (Findable, Accessible, Interoperable, and Reusable), and unified framework for biomarker knowledge exploration and discovery.
]]></description>
<dc:creator>Masood, D.</dc:creator>
<dc:creator>Kim, M.</dc:creator>
<dc:creator>Vora, J.</dc:creator>
<dc:creator>Kahsay, R.</dc:creator>
<dc:creator>McNeeley, P.</dc:creator>
<dc:creator>Kim, S.</dc:creator>
<dc:creator>Kulkarni, S. V.</dc:creator>
<dc:creator>Natale, D. A.</dc:creator>
<dc:creator>Maurya, M.</dc:creator>
<dc:creator>Ramachandran, S.</dc:creator>
<dc:creator>Gupta, S.</dc:creator>
<dc:creator>Bologa, C. G.</dc:creator>
<dc:creator>DeNapoli, T. S.</dc:creator>
<dc:creator>Metzger, V. T.</dc:creator>
<dc:creator>Kumar, P.</dc:creator>
<dc:creator>Ahmed, N.</dc:creator>
<dc:creator>Evangelista, J. E.</dc:creator>
<dc:creator>Kelly, S. C.</dc:creator>
<dc:creator>Sepulveda, J.</dc:creator>
<dc:creator>Ma'ayan, A.</dc:creator>
<dc:creator>Silverstein, J.</dc:creator>
<dc:creator>Taylor, D. M.</dc:creator>
<dc:creator>Crichton, D. J.</dc:creator>
<dc:creator>Mahabal, A.</dc:creator>
<dc:creator>Yang, J. J.</dc:creator>
<dc:creator>Lambert, C. G.</dc:creator>
<dc:creator>Subramaniam, S.</dc:creator>
<dc:creator>Tiemeyer, M.</dc:creator>
<dc:creator>Ranzinger, R.</dc:creator>
<dc:creator>Mazumder, R.</dc:creator>
<dc:date>2026-01-27</dc:date>
<dc:identifier>doi:10.64898/2026.01.26.701395</dc:identifier>
<dc:title><![CDATA[BiomarkerKB: FAIR and Integrated Biomarker Knowledge Connecting Biomolecular and Clinical Data Types]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-01-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.01.28.702367v1?rss=1">
<title>
<![CDATA[
Death & Chemotaxis: Bacterial chemotaxis enables collective escape from phage predation 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.01.28.702367v1?rss=1</link>
<description><![CDATA[
Bacteriophages ("phage") are viruses that prey on bacteria in diverse environments, from biological tissues to soils. In many of these environments, bacterial hosts are constantly migrating, yet how bacterial migration is influenced by phage predation remains poorly understood. Using transparent granular hydrogels that mimic natural habitats, we directly visualize populations of motile Escherichia coli encountering lytic T4 phage. Unexpectedly, we find that even in phage-rich environments, bacteria successfully form chemotactic fronts that enable them to migrate over large distances without needing to develop phage resistance. Higher phage concentrations delay front formation but not steady-state front speed or shape. By combining our experiments with biophysical modeling, we demonstrate that this phenomenon arises from the ability of cells to collectively outrun trailing phage bursts--as quantified by a dimensionless "escape parameter" comparing chemotactic and predation rates. This work thus reveals and provides mechanistic insight into the role of cell motility in shaping phage-bacteria interactions in spatially-extended environments.
]]></description>
<dc:creator>Muir, V. G.</dc:creator>
<dc:creator>Martinez-Calvo, A.</dc:creator>
<dc:creator>Wingreen, N. S.</dc:creator>
<dc:creator>Datta, S. S.</dc:creator>
<dc:date>2026-01-28</dc:date>
<dc:identifier>doi:10.64898/2026.01.28.702367</dc:identifier>
<dc:title><![CDATA[Death & Chemotaxis: Bacterial chemotaxis enables collective escape from phage predation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-01-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.01.29.702630v1?rss=1">
<title>
<![CDATA[
Principles of in situ protein sequencing: expansion microscopy-adapted Edman degradation and amino acid recognition 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.01.29.702630v1?rss=1</link>
<description><![CDATA[
The ability to map protein identity, with resolution sufficient to infer interactions, would support analysis of how proteins work together, or malfunction, in biological processes and diseases. Although several emerging technologies aim towards single-molecule protein sequencing, they require proteins to be removed from the nanoscale spatial context of cells and tissues. Expansion microscopy (ExM) has facilitated a diversity of chemical analyses by isotropically separating molecules throughout a specimen after permeation via a charged hydrogel, followed by gel swelling. Here, we adapt key protein sequencing steps - Edman degradation and amino acid recognition - to the ExM gel context. Using testbed peptides in ExM gels, we show that N-terminal amino acids can be recognized over multiple cycles of in-gel Edman degradation. These results establish principles of in situ protein sequencing and provide a framework for future in situ protein sequencing developments, including the development of higher specificity and affinity amino acid binders.
]]></description>
<dc:creator>Mitchell, C. M.</dc:creator>
<dc:creator>Tavana, S. Z.</dc:creator>
<dc:creator>Peng, J.</dc:creator>
<dc:creator>Wang, H.</dc:creator>
<dc:creator>Shi, J.</dc:creator>
<dc:creator>Zhang, C.</dc:creator>
<dc:creator>Evgeniou, L.</dc:creator>
<dc:creator>Domecillo, M.</dc:creator>
<dc:creator>Wang, S.</dc:creator>
<dc:creator>Estandian, D. M.</dc:creator>
<dc:creator>Choueiri, A. G.</dc:creator>
<dc:creator>Wong, E.</dc:creator>
<dc:creator>Dohadwala, S.</dc:creator>
<dc:creator>Polizzi, N.</dc:creator>
<dc:creator>Kiessling, L. L.</dc:creator>
<dc:creator>Boyden, E. S.</dc:creator>
<dc:date>2026-01-30</dc:date>
<dc:identifier>doi:10.64898/2026.01.29.702630</dc:identifier>
<dc:title><![CDATA[Principles of in situ protein sequencing: expansion microscopy-adapted Edman degradation and amino acid recognition]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-01-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.01.30.702911v1?rss=1">
<title>
<![CDATA[
Science should be machine-readable 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.01.30.702911v1?rss=1</link>
<description><![CDATA[
We develop a machine-automated approach for extracting results from papers, which we assess via a comprehensive review of the entire eLife corpus. Our method facilitates a direct comparison of machine and peer review, and sheds light on key challenges that must be overcome in order to facilitate AI-assisted science. In particular, the results point the way towards a machine-readable framework for disseminating scientific information. We therefore argue that publication systems should optimize separately for the dissemination of data and results versus the conveying of novel ideas, and the former should be machine-readable.
]]></description>
<dc:creator>Booeshaghi, A. S.</dc:creator>
<dc:creator>Luebbert, L.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2026-02-02</dc:date>
<dc:identifier>doi:10.64898/2026.01.30.702911</dc:identifier>
<dc:title><![CDATA[Science should be machine-readable]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-02-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.02.01.703179v1?rss=1">
<title>
<![CDATA[
Quantitative measurement of synthetic repression curves reveals design challenges for genetic circuit engineering under growth arrest 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.02.01.703179v1?rss=1</link>
<description><![CDATA[
Despite the fact that microbes in natural environments spend most of their time in growth arrest, we understand little about how this physiological state affects the performance of engineered genetic circuits. Here, we measure repression curves from a library of genetic NOT gates at single-cell resolution in Escherichia coli under both active growth and growth arrest to systematically investigate how growth arrest affects circuit behavior. We find that the impact of growth arrest on circuit performance is almost entirely dominated by a single effect: a >100-fold reduction in unrepressed expression levels. Growth arrest caused gene expression noise to increase moderately and had only minimal impacts on the sensitivity and sharpness of the repression curves. Our work shows both that conventional genetic circuit design paradigms are currently insufficient to develop circuits that can function properly under growth arrest, but also that addressing the reduction in just a single performance parameter would be sufficient to resolve this problem. This work expands our understanding of bacterial gene regulation under growth arrest and lays the groundwork for new design paradigms that will be essential in ensuring the safe and reliable performance of synthetic biology systems in real-world environments.



O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=87 SRC="FIGDIR/small/703179v1_ufig1.gif" ALT="Figure 1">
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]]></description>
<dc:creator>Marken, J. P.</dc:creator>
<dc:creator>Prator, M. L.</dc:creator>
<dc:creator>Hay, B. A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2026-02-02</dc:date>
<dc:identifier>doi:10.64898/2026.02.01.703179</dc:identifier>
<dc:title><![CDATA[Quantitative measurement of synthetic repression curves reveals design challenges for genetic circuit engineering under growth arrest]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-02-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.02.02.703255v1?rss=1">
<title>
<![CDATA[
A unified pipeline for discovering previously unknown enzyme activities 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.02.02.703255v1?rss=1</link>
<description><![CDATA[
Enzymes catalyze diverse chemical transformations and offer a sustainable approach to both breaking and making chemical bonds. However, finding an enzyme capable of performing a specific chemical reaction remains a challenge. We developed a new framework, Enzyme-toolkit (Enzyme-tk), that integrates 23 open-source tools to enable the discovery of enzymes that have activity toward a specific target reaction. Additionally, we introduce two new methods to facilitate enzyme discovery: (1) Func-e, an ML tool that searches large databases for enzymes that potentially catalyze a specific chemical transformation and (2) Oligopoolio, a gene assembly approach that reduces the cost of accessing protein sequences and thus the barrier to their experimental validation. We applied Enzyme-tk to find enzymes for chemical degradation of two man-made pollutants, di-(2-ethylhexyl) phthalate (DEHP) and triphenyl phosphate (TPP). We demonstrate that new, previously unannotated enzymes with favorable characteristics, such as high thermostability, can be identified using Enzyme-tk for reactions that are dissimilar to the training set.
]]></description>
<dc:creator>Mora, A.</dc:creator>
<dc:creator>Reisenbauer, J. C.</dc:creator>
<dc:creator>Schmid, H.</dc:creator>
<dc:creator>Miyazaki, I.</dc:creator>
<dc:creator>Long, Y.</dc:creator>
<dc:creator>Yang, J.</dc:creator>
<dc:creator>OMeara, R.</dc:creator>
<dc:creator>Arnold, F. H.</dc:creator>
<dc:date>2026-02-02</dc:date>
<dc:identifier>doi:10.64898/2026.02.02.703255</dc:identifier>
<dc:title><![CDATA[A unified pipeline for discovering previously unknown enzyme activities]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-02-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.02.02.703150v1?rss=1">
<title>
<![CDATA[
Stem cell control and cancer initiation by an autocrine, injury-activated Igf complex 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.02.02.703150v1?rss=1</link>
<description><![CDATA[
Stem cells rapidly proliferate after injury to repair damaged tissue, and chronic injury predisposes to cancer. However, injury-activated mitogens, the mechanisms that keep them inactive until injury, and their role in cancer are not understood. Here we identify Igf2 as the injury-activated mitogen for neuroendocrine stem cells, a facultative airway stem cell and origin of small cell lung cancer. Igf2 is constitutively produced by the stem cells but sequestered in inactive form by co-expressed Igf binding proteins. Injury releases Igf2 and induces proliferation by activating its receptors and repressing Rb tumor suppressor, which normally enforces stem cell quiescence. Persistent pathway activation initiates oncogenesis. Thus, in addition to its classical hormonal roles in physiology, growth, and aging, Igf operates locally with Igf binding proteins and Rb to control injury-induced stem cell activation and cancer. This pathway may also control related stem cells and cancers of the body and brain.
]]></description>
<dc:creator>Zhang, Y.</dc:creator>
<dc:creator>Ouadah, Y.</dc:creator>
<dc:creator>Liu, Y.</dc:creator>
<dc:creator>Kumar, M.</dc:creator>
<dc:creator>Morck, M.</dc:creator>
<dc:creator>Krasnow, M. A.</dc:creator>
<dc:date>2026-02-04</dc:date>
<dc:identifier>doi:10.64898/2026.02.02.703150</dc:identifier>
<dc:title><![CDATA[Stem cell control and cancer initiation by an autocrine, injury-activated Igf complex]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-02-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.02.06.703857v1?rss=1">
<title>
<![CDATA[
Regenerative base editing enables deep lineage recording 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.02.06.703857v1?rss=1</link>
<description><![CDATA[
Reconstructing the lineage histories of individual cells can reveal the dynamics of developmental and disease processes. In engineered recording systems, cells stochastically edit synthetic barcode sequences as they proliferate, creating distinct, heritable edit patterns that can be used to reconstruct the lineage trees relating individual cells in a manner analogous to phylogenetic reconstruction. However, recording depth is often limited by the kinetics of the editing process: the rate of editing declines exponentially over time for an array of independently editable targets, leading to most edits occurring in early generations. Here, we introduce the hypercascade, a regenerative molecular recording system that takes advantage of the predictability of A-to-G base editing to progressively create new target sites over time. The hypercascade packs 4 editable target sites in every 20 bp of sequence, enabling high density information storage. More importantly, the hypercascades regenerative logic leads to an approximately constant rate of mutation accumulation over time. This in turn facilitates reconstruction of deep lineage relationships. We demonstrate this by reconstructing trees spanning 23 days of editing and approximately 17 generations after a single polyclonal engineering step. Finally, simulations show that the hypercascade has the potential to record chromatin state transition dynamics across multiple genomic loci in parallel. The hypercascade thus provides a flexible and broadly useful tool for molecular recording.
]]></description>
<dc:creator>Chadly, D. M.</dc:creator>
<dc:creator>Hadas, R.</dc:creator>
<dc:creator>Klock, L.</dc:creator>
<dc:creator>Yue, J.</dc:creator>
<dc:creator>Horns, F.</dc:creator>
<dc:creator>Askary, A.</dc:creator>
<dc:creator>Granados, A. A.</dc:creator>
<dc:creator>Bouckaert, R.</dc:creator>
<dc:creator>Lois, C.</dc:creator>
<dc:creator>Cai, L.</dc:creator>
<dc:creator>Elowitz, M. B.</dc:creator>
<dc:date>2026-02-07</dc:date>
<dc:identifier>doi:10.64898/2026.02.06.703857</dc:identifier>
<dc:title><![CDATA[Regenerative base editing enables deep lineage recording]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-02-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.02.16.706223v1?rss=1">
<title>
<![CDATA[
Differential analysis of genomics count data with edge 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.02.16.706223v1?rss=1</link>
<description><![CDATA[
The edgeR Bioconductor package is one of the most widely used tools for differential expression analysis of count-based genomics data. Despite its popularity, the R-only implementation limits its integration with the Python-centric ecosystem that has become dominant in single-cell genomics. We present edgePython, a Python port of edgeR 4.8.2 that extends the framework with a negative binomial-gamma mixed model for multi-subject single-cell analysis and empirical Bayes shrinkage of cell-level dispersion.
]]></description>
<dc:creator>Pachter, L.</dc:creator>
<dc:date>2026-02-18</dc:date>
<dc:identifier>doi:10.64898/2026.02.16.706223</dc:identifier>
<dc:title><![CDATA[Differential analysis of genomics count data with edge]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-02-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.02.17.705849v1?rss=1">
<title>
<![CDATA[
Structural evolution of the MTCH family of mitochondrial insertases 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.02.17.705849v1?rss=1</link>
<description><![CDATA[
Here we demonstrated that MTCH2 is the defining member of a large family of mitochondrial outer membrane (OM) insertases. The MTCH family is conserved across holozoa and has diverged from the solute carrier 25 transporters. The cryoelectron microscopy structure of the 33 kDa human MTCH2 revealed that evolution of its insertase activity required loss of a transmembrane helix, which created a lipid-accessible hydrophilic groove stabilized by its unique, structured C-terminus. Mutational analyses showed that MTCH insertase activity is attenuated, while experimental structures of hyperactive mutants demonstrated that the hydrophobicity, charge, and size of the residues that line its groove regulated MTCH function. Leveraging the MTCH2 structure, we identified the plant OM insertase, and proposed a universal mechanism for OM insertion across all kingdoms of life.
]]></description>
<dc:creator>Stevens, T. A.</dc:creator>
<dc:creator>Luo, Z.</dc:creator>
<dc:creator>Lee, C.</dc:creator>
<dc:creator>Hazu, M.</dc:creator>
<dc:creator>Galatis, E. G.</dc:creator>
<dc:creator>Inglis, A. J.</dc:creator>
<dc:creator>Guna, A.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:date>2026-02-18</dc:date>
<dc:identifier>doi:10.64898/2026.02.17.705849</dc:identifier>
<dc:title><![CDATA[Structural evolution of the MTCH family of mitochondrial insertases]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-02-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.02.19.706881v1?rss=1">
<title>
<![CDATA[
Structural basis of metalloid transport by the arsenite efflux pump ArsB 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.02.19.706881v1?rss=1</link>
<description><![CDATA[
Bacteria resist toxic arsenite (AsIII) in their environments by actively pumping the metalloid out of the cell via efflux pumps such as ArsB. However, the mechanism of extrusion remains poorly understood, which hinders the development of engineered bioremediation strategies. We report high-resolution cryo-EM structures of ArsB from the arsenic-tolerant bacterium Leptospirillum ferriphilum. ArsB adopts an inverted two-fold repeat architecture resembling that of other ion transporter (IT) superfamily proteins. Structures determined in the presence of AsIII and antimonite (SbIII) reveal that the metalloid substrates interact with polar residues at the core of the transmembrane domain primarily via hydrogen bonding. Mutagenesis and in vivo functional assays support these interactions. Our ArsB structures represent an  inward-facing conformation, where the metalloid-binding site is exposed to the cytoplasm, suitable for metalloid capture. Furthermore, we demonstrate that AsIII resistance conferred by ArsB varies with external pH, supporting that ArsB is a proton (H+)-coupled secondary transporter. Mutagenesis, in vivo functional assays, and pKa estimation imply that conserved aspartate residues near the metalloid-binding site likely mediate the H+-coupling mechanism. Our findings provide structural insights into metalloid recognition and H+/metalloid antiport in ArsB, laying a foundation for further elucidation of the molecular basis of toxic metalloid detoxification in bacteria.
]]></description>
<dc:creator>Mahajan, S.</dc:creator>
<dc:creator>Demirer, K.</dc:creator>
<dc:creator>Clemons, W. M.</dc:creator>
<dc:creator>Rees, D. C.</dc:creator>
<dc:date>2026-02-20</dc:date>
<dc:identifier>doi:10.64898/2026.02.19.706881</dc:identifier>
<dc:title><![CDATA[Structural basis of metalloid transport by the arsenite efflux pump ArsB]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-02-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.02.22.707325v1?rss=1">
<title>
<![CDATA[
Nucleotide-level chemical reaction network modeling enables quantitative prediction of reconstituted cell-free expression system 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.02.22.707325v1?rss=1</link>
<description><![CDATA[
Cell-free expression systems offer a method for rapid prototyping of DNA circuits and functional protein synthesis. While crude extracts remain a black box with many components carrying out unknown reactions, PURE contains only the required transcription and translation components for protein production. All proteins and small molecules are at known concentrations, enabling detailed modeling for reliable computational predictions. However, there is little to no experimental data supporting the expression of target proteins for PURE-based models. In this work, we generalized the PURE detailed translation model for proteins with arbitrary amino acid compositions and lengths. We then built a chemical reaction network for transcription in PURE, validating the transcription models using DNA expression for the malachite-green aptamer (MGapt) to measure mRNA production. Lastly, we coupled the transcription and the generalized translation models to create a PURE protein synthesis model built purely of mass-action reactions. We used the combined model to capture the kinetics of MGapt and deGFP expressed from plasmids at varying concentrations.
]]></description>
<dc:creator>Jurado, Z.</dc:creator>
<dc:creator>Pandey, A.</dc:creator>
<dc:creator>Murray, R. M.</dc:creator>
<dc:date>2026-02-23</dc:date>
<dc:identifier>doi:10.64898/2026.02.22.707325</dc:identifier>
<dc:title><![CDATA[Nucleotide-level chemical reaction network modeling enables quantitative prediction of reconstituted cell-free expression system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-02-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.01.708836v1?rss=1">
<title>
<![CDATA[
The orbitofrontal cortex constructs allocentric schemas by integrating dynamic mobile agents with static environmental anchors 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.01.708836v1?rss=1</link>
<description><![CDATA[
Scene construction involves the automatic synthesis of fragmented visual inputs into coherent mental models. While previous work has focused on static landscapes, real-world scenes require integrating dynamic agents with stable environmental anchors. We investigated the neural hierarchy underlying this transformation using an automatic space-encoding task in a 3D virtual-reality environment and fMRI representational similarity analysis. Results revealed functional segregation across visual cortex: the superior lateral occipital cortex encoded the first-person perspective of mobile character layouts, whereas the lingual gyrus and occipital fusiform cortex represented environments specified by visible landmarks. The orbitofrontal cortex integrated these streams into an allocentric spatial schema, capturing relational geometry beyond the current visual field. Following encoding, these representations were expressed in the anterior hippocampus for self-localization. Together, the findings demonstrate an automatic hierarchical transformation in which the OFC serves as a central scaffold for constructing allocentric spatial frameworks underlying stable scene representation.
]]></description>
<dc:creator>Zhu, Z.</dc:creator>
<dc:creator>Zhang, B.</dc:creator>
<dc:creator>Zhang, X.</dc:creator>
<dc:creator>Naya, Y.</dc:creator>
<dc:date>2026-03-03</dc:date>
<dc:identifier>doi:10.64898/2026.03.01.708836</dc:identifier>
<dc:title><![CDATA[The orbitofrontal cortex constructs allocentric schemas by integrating dynamic mobile agents with static environmental anchors]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.04.709349v1?rss=1">
<title>
<![CDATA[
Single-Cell Genomics Decontamination with CellSweep 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.04.709349v1?rss=1</link>
<description><![CDATA[
Single-cell genomics technologies enable high-throughput cell profiling, but technical contamination remains an obstacle to accurate downstream analysis. Free-floating ambient molecules released from lysed cells and global bulk contamination introduced during library preparation can distort molecular profiles. These artifacts can obscure cellular identities and reduce the reliability of differential analysis or clustering results. We present an efficient and effective approach to removing ambient and bulk contamination that can be applied to data generated from a wide variety of technologies. We show that our tool, CellSweep, outperforms other methods to remove artifacts using numerous benchmarks.
]]></description>
<dc:creator>Caskey, M.</dc:creator>
<dc:creator>Rich, J.</dc:creator>
<dc:creator>Weber, R.</dc:creator>
<dc:creator>Mortazavi, A.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Hallgrimsdottir, I. B.</dc:creator>
<dc:date>2026-03-06</dc:date>
<dc:identifier>doi:10.64898/2026.03.04.709349</dc:identifier>
<dc:title><![CDATA[Single-Cell Genomics Decontamination with CellSweep]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.06.710139v1?rss=1">
<title>
<![CDATA[
Multitasking boosts muscular endurance task performance due to elevated arousal level unattainable by the endurance task alone 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.06.710139v1?rss=1</link>
<description><![CDATA[
Multitasking is generally regarded as detrimental to performance. This deterioration effect is typically explained by the interference among tasks due to the limited capacity of information-processing resources, which in turn reduces the performance in each task. Contrary to this general view, we report evidence for a facilitation effect of multitasking on performance. This facilitation effect was observed in multitasking on a handgrip muscular endurance task and cognitive task, which are known to have little interference with each other. Specifically, we found that performance in the endurance task was facilitated with the difficulty of the concurrent cognitive task. This facilitation effect was mediated by additional pupil dilation due to the cognitive task. Increased effort with the difficulty of the cognitive task cannot explain the facilitated performance in the irrelevant endurance task. Instead, they suggest that the cognitive task elevated overall arousal to a level unattainable by the endurance task alone, which in turn facilitated performance in the irrelevant endurance task. To further test this arousal account, we manipulated participants motivation to the cognitive task by reward without changing its difficulty and found the same pattern of results. Thus, it is not effort or motivation specific to the cognitive task but rather overall arousal level that underlies the facilitation effect. These results unveiled a previously overlooked mechanism: a multitasking-induced arousal boost. Our findings suggest that multitasking can facilitate performance when the net effect of adding a concurrent task is governed less by the capacity limitation and more by the elevation of overall arousal.
]]></description>
<dc:creator>Nagisa, S.</dc:creator>
<dc:creator>Oblak, E.</dc:creator>
<dc:creator>Shimojo, S.</dc:creator>
<dc:creator>Shibata, K.</dc:creator>
<dc:date>2026-03-10</dc:date>
<dc:identifier>doi:10.64898/2026.03.06.710139</dc:identifier>
<dc:title><![CDATA[Multitasking boosts muscular endurance task performance due to elevated arousal level unattainable by the endurance task alone]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.13.711726v1?rss=1">
<title>
<![CDATA[
Statistical BURST imaging for high-fidelity biomolecular ultrasound 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.13.711726v1?rss=1</link>
<description><![CDATA[
Ultrasound is emerging as a method for molecular and cellular imaging by connecting the versatile physics of sound waves to protein-based contrast agents such as gas vesicles (GVs). BURST is a common imaging mode that leverages the strong, transient echoes generated when GVs collapse under acoustic pressure to enable highly sensitive ultrasound visualization of cells and biomolecules, down to the single cell level. However, BURST is vulnerable to fluctuating background signals, with large-amplitude fluctuations in scattering, as often present in vivo, obscuring genuine GV responses. In this study, we mathematically examine this limitation and show that incorporating statistical metrics such as correlation or temporal contrast-to-noise ratio effectively suppresses unwanted non-GV voxels and quantifies detection confidence, including in image sequences in which GV collapse spans multiple frames. Compared with prior methods, our approach enhances the clarity of BURST images and provides probabilistic interpretations of GV signals, facilitating more reliable analysis of ambiguous in vivo molecular imaging, as we demonstrate in imaging tumor-homing probiotics and gene expression in the brain.
]]></description>
<dc:creator>Lee, S.</dc:creator>
<dc:creator>Shivaei, S.</dc:creator>
<dc:creator>Shapiro, M. G.</dc:creator>
<dc:date>2026-03-17</dc:date>
<dc:identifier>doi:10.64898/2026.03.13.711726</dc:identifier>
<dc:title><![CDATA[Statistical BURST imaging for high-fidelity biomolecular ultrasound]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.18.712767v1?rss=1">
<title>
<![CDATA[
Sentinel plants enable quantitative monitoring of bioavailable nitrate in soils and microbial environments 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.18.712767v1?rss=1</link>
<description><![CDATA[
Microbial transformations of nitrogen in soils strongly influence plant nutrition and ecosystem function, yet these processes remain difficult to monitor. Existing approaches rely largely on destructive soil sampling and laboratory analysis, limiting the ability to track nitrate dynamics in situ. Here, we engineer "sentinel plants," genetically encoded plant biosensors that convert nitrate perception into a quantitative signal reporting plant-accessible nitrate. The sensor uses a synthetic nitrate-responsive promoter coupled to a ratiometric luciferase reporter, enabling high-dynamic-range measurements. Sentinel plants exhibit a dose-dependent, reversible nitrate response with high specificity over alternative nitrogen sources. In agricultural soils from multiple California field sites, sensor output closely tracked analytically measured nitrate concentrations and resolved nitrate amendments without destructive extraction. Beyond environmental sensing, sentinel plants enabled screening of nitrogen-fixing microbial communities and the detection of microbially generated nitrate in both liquid culture and soil systems. Using this platform, we identified a minimal three-member microbial consortium capable of converting atmospheric nitrogen into nitrate via sequential nitrogen fixation and nitrification. This consortium increased tissue nitrate accumulation and plant fresh weight, demonstrating that sentinel plants can both monitor nitrate availability and identify microbial communities that enhance plant growth.

Significance StatementNitrogen availability in soils fluctuates across space and time, yet most measurements rely on extracting soil samples and analyzing them in the laboratory. Such measurements provide only snapshots of nitrogen status and do not necessarily reflect the nitrogen that plants themselves experience. Here, we engineer plants that act as living nitrate sensors by converting nitrate perception into a measurable optical signal. Because these sensors operate within intact plants, they report nitrate availability as integrated through plant uptake and physiology rather than through chemical extraction alone. Using this platform, we tracked nitrate levels in agricultural soils and identified a minimal microbial consortium capable of converting atmospheric nitrogen into plant-available nitrate. This plant-based sensing strategy enables direct monitoring of nitrogen dynamics in soils and microbial environments, providing a platform for identifying microbial communities that enhance nitrogen availability for crops.
]]></description>
<dc:creator>Li, E.</dc:creator>
<dc:creator>Berruto, C.</dc:creator>
<dc:creator>Oz, T.</dc:creator>
<dc:creator>Grillo, E.</dc:creator>
<dc:creator>Griffin, C.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Jones, J.</dc:creator>
<dc:creator>Demirer, G. S.</dc:creator>
<dc:date>2026-03-23</dc:date>
<dc:identifier>doi:10.64898/2026.03.18.712767</dc:identifier>
<dc:title><![CDATA[Sentinel plants enable quantitative monitoring of bioavailable nitrate in soils and microbial environments]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.23.713735v1?rss=1">
<title>
<![CDATA[
Sentinel Plants Enable Aboveground Detection of Belowground Soil Microbial Activity 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.23.713735v1?rss=1</link>
<description><![CDATA[
Rhizosphere microbial processes play a central role in soil function and plant health yet remain difficult to monitor noninvasively. Engineered sentinel plants that use bacterial-to-plant communication channels are promising. However, no such efforts have thus far enabled a detectable aboveground response in the sentinel plant. Here, we optimize a previously described synthetic bacteria-to-plant communication channel based on the p-coumaroyl-homoserine lactone (pC-HSL) signaling molecule in plants to function as aboveground sentinels of belowground microbial activities. Arabidopsis thaliana sentinel plants harboring this optimized circuit detect root-applied pC-HSL at concentrations as low as 30 nM in roots and 3 M in leaves, demonstrating long-distance signal transmission from below ground to aboveground tissues. Moreover, sentinel plants report pC-HSL production by engineered Escherichia coli and Pseudomonas putida colonizing plant roots in both plate and soil assays. These results establish an engineered plant platform that converts rhizosphere microbial activity into a visible aboveground signal, enabling a minimally invasive platform for monitoring rhizosphere microbial gene expression and for precision agriculture and soil management.
]]></description>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Marken, J. P.</dc:creator>
<dc:creator>Li, E.</dc:creator>
<dc:creator>Tarr, P. T.</dc:creator>
<dc:creator>Meyerowitz, E.</dc:creator>
<dc:creator>Demirer, G. S.</dc:creator>
<dc:date>2026-03-24</dc:date>
<dc:identifier>doi:10.64898/2026.03.23.713735</dc:identifier>
<dc:title><![CDATA[Sentinel Plants Enable Aboveground Detection of Belowground Soil Microbial Activity]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.23.713577v1?rss=1">
<title>
<![CDATA[
Transient contractility attenuation reprograms epithelial cells into a protrusion-driven state that drives tissue fluidization 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.23.713577v1?rss=1</link>
<description><![CDATA[
Collective cell migration drives tissue morphogenesis, repair and remodeling, and is often accompanied by transitions from solid-like to fluid-like states. While such tissue fluidization has been linked to physical parameters such as cell density, shape and activity, how it is actively regulated by mechano-chemical interplay remains unclear. Previous research has shown that transient attenuation of actomyosin contractility induces a transition from pulsatile, spatially confined motion to coherent, persistent long-range collective flow; however, the underlying cellular and signaling mechanisms remain unclear. Here we uncover the mechanistic basis by which transient perturbation of cell contractility reprograms the migration mode of confluent epithelial cells into a leader-like, fluidizing state, by combining kinase-reporter live imaging, force measurements and mathematical modeling. This transition arises from coordinated changes in cell morphology, mechanics, and signaling, including reduced cortical tension, enhanced cell-substrate adhesion and traction forces, and increased tissue deformability. At the signaling level, this process is accompanied by a rewiring of extracellular signal-regulated kinase (ERK)-mediated mechanotransduction toward a protrusion-coupled mode that sustains migration even under fully confluent conditions. Consistently, a multicellular computational model further demonstrates that protrusion-driven migration is sufficient to promote shape-velocity alignment and drive a transition from caged to flocking-like collective states. Together, our results identify transient mechanical relaxation as a trigger for an intrinsic leader-like state that fluidizes epithelial confluent tissues through coordinated remodeling of cytoskeletal, adhesive, and signaling systems.
]]></description>
<dc:creator>WP, S.</dc:creator>
<dc:creator>Liu, S.</dc:creator>
<dc:creator>Nguyen, T. P.</dc:creator>
<dc:creator>Mishra, P. K.</dc:creator>
<dc:creator>Pratiman, D.</dc:creator>
<dc:creator>Gupta, A. S.</dc:creator>
<dc:creator>Hirashima, T.</dc:creator>
<dc:date>2026-03-25</dc:date>
<dc:identifier>doi:10.64898/2026.03.23.713577</dc:identifier>
<dc:title><![CDATA[Transient contractility attenuation reprograms epithelial cells into a protrusion-driven state that drives tissue fluidization]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.23.713767v1?rss=1">
<title>
<![CDATA[
Highly Stable Mn(V)-Nitrido and Nitrogen-Atom Transfer Reactivity within a De Novo Protein 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.23.713767v1?rss=1</link>
<description><![CDATA[
High-valent metal-nitrido species are powerful nitrogen-atom transfer intermediates but remain difficult to access and control due to intrinsic instability and bimolecular N-N coupling pathways. Herein, we report the first formation of a high-valent Mn(V)-nitrido complex within a de novo designed protein scaffold and demonstrate that a reactive precursor to this species can be catalytically intercepted for enantioselective aziridination. A Mn(V){equiv}N unit derived from an abiological diphenyl porphyrin is confined within a designed helical bundle protein, where the protein environment suppresses bimolecular decay and enables detailed spectroscopic characterization. Electron paramagnetic resonance, resonance Raman, and circular dichroism spectroscopies confirm formation of a low-spin Mn(V)-nitrido species that is stable for weeks at room temperature and exhibits minimal perturbation of the Mn{equiv}N unit upon modulation of the axial histidine ligand, while catalytic activity and stereochemical outcome are sensitive to its presence. Mechanistic studies identify monochloramine (NH2Cl) as the operative nitrogen-atom donor and support the involvement of a transient Mn-bound N-transfer intermediate en route to nitrido formation. Under catalytic conditions, this intermediate is inter-cepted to perform aziridination with TON {approx} 180 and an enantiomeric ratio of 65:35. Together, these results establish de novo protein design as a platform for stabilizing high-valent metal-nitrido species and harnessing their reactivity for nitrogen-atom transfer chemistry beyond the limits of natural metalloenzymes and small-molecule catalysts.
]]></description>
<dc:creator>Thomas, J.</dc:creator>
<dc:creator>Yadav, S.</dc:creator>
<dc:creator>Oyala, P. H.</dc:creator>
<dc:creator>Carta, V.</dc:creator>
<dc:creator>Goldberg, D. P.</dc:creator>
<dc:creator>Mann, S. I.</dc:creator>
<dc:date>2026-03-25</dc:date>
<dc:identifier>doi:10.64898/2026.03.23.713767</dc:identifier>
<dc:title><![CDATA[Highly Stable Mn(V)-Nitrido and Nitrogen-Atom Transfer Reactivity within a De Novo Protein]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.24.713977v1?rss=1">
<title>
<![CDATA[
Chiral methionine oxidation reagents reveal stereospecific proteome modifications 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.24.713977v1?rss=1</link>
<description><![CDATA[
Life is predicated on chirality, a molecular asymmetry akin to the left and right versions of human hands. Here we show that privileged protein residues are predisposed for chiral regulation. We developed enantiomeric oxaziridine reagents that systematically identify pro-(S) and pro-(R) methionine oxidation sites across proteomes that can be erased by stereospecific methionine sulfoxide reductase enzymes A and B, respectively. These probes reveal that chiral regulation of methionine oxidation-reduction processes can allosterically regulate protein function, as shown in cell and murine models of oxidative stress where selective (R)-methionine sulfoxide formation on M69 of biphenyl hydrolase-like protein leads to hydrolase inhibition and amplification of proteome N-homocysteinylation modifications. This work introduces a platform for characterizing sites of asymmetric methionine oxidation and the functional consequences concomitant with an individual chiral single-atom modification.
]]></description>
<dc:creator>Gonzalez-Valero, A.</dc:creator>
<dc:creator>Page, A. C. S.</dc:creator>
<dc:creator>Bertoch, J. M.</dc:creator>
<dc:creator>Alsarhan, F.</dc:creator>
<dc:creator>Kim, J.</dc:creator>
<dc:creator>Alazali, A. A.</dc:creator>
<dc:creator>Srinivas, R. R.</dc:creator>
<dc:creator>Xie, X.</dc:creator>
<dc:creator>Reeves, A. G.</dc:creator>
<dc:creator>Skakuj, K.</dc:creator>
<dc:creator>Coffey, T. G.</dc:creator>
<dc:creator>Virgil, S. C.</dc:creator>
<dc:creator>Nafie, J.</dc:creator>
<dc:creator>He, D.</dc:creator>
<dc:creator>Dao, N.</dc:creator>
<dc:creator>Gunawan, A. L.</dc:creator>
<dc:creator>Dukor, R.</dc:creator>
<dc:creator>Stahl, A.</dc:creator>
<dc:creator>Toste, F. D.</dc:creator>
<dc:creator>Chang, C. J.</dc:creator>
<dc:date>2026-03-26</dc:date>
<dc:identifier>doi:10.64898/2026.03.24.713977</dc:identifier>
<dc:title><![CDATA[Chiral methionine oxidation reagents reveal stereospecific proteome modifications]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.24.713825v1?rss=1">
<title>
<![CDATA[
Stabilized gp120-specific CD4 for next-generation HIV-1 inhibitors 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.24.713825v1?rss=1</link>
<description><![CDATA[
HIV-1 Envs gp120 subunit uses the T-cell coreceptor CD4 to enter host cells in a manner that prevents the evolution of host resistance by sharing the binding epitope with the footprint of CD4s natural ligands, class II MHC proteins1,2. Consequently, CD4-containing biologics, such as CD4-Ig3,4 and derivatives5-9, benefit from this conserved relationship and are promising broad-acting anti-HIV-1 agents that are resistant to viral mutational escape10. However, these biologics suffer from short serum half-lives in humans11,12 and animals3,13, likely due to CD4s poor thermostability14 and/or off-target class II MHC binding15. This latter property also warrants caution for CD4-containing biologics that could indiscriminately recruit Fc-dependent effector functions against uninfected cells and/or compete with host CD4 for class II MHC during T cell interactions with antigen-presenting cells. Here, we describe gp120-specific CD4 (gCD4), which exhibits enhanced thermostability and retains Env, but not class II MHC, binding. CD4-Ig variants incorporating gCD4 did not bind class II MHC on human B cells, displayed greater longevity in human tonsil organoid cultures, showed half-lives equivalent to therapeutic IgG antibodies in mice, and neutralized HIV-1 more broadly and potently compared to the original CD4-Ig molecules. Encouragingly, one variant neutralized 100% of a panel of clinically-relevant HIV-1 strains at titers correlating to infection prevention in humans, outperforming known broadly neutralizing antibodies16,17. Thus, gCD4 holds promise for the development of new CD4-containing biologics with best-in-class specificity, pharmacokinetic properties, and neutralization breadth and potency.
]]></description>
<dc:creator>Bahn-Suh, A. J.</dc:creator>
<dc:creator>Caldera, L. F.</dc:creator>
<dc:creator>Gnanapragasam, P. N. P.</dc:creator>
<dc:creator>Keeffe, J. R.</dc:creator>
<dc:creator>Seaman, M. S.</dc:creator>
<dc:creator>Bjorkman, P. J.</dc:creator>
<dc:creator>Mayo, S. L.</dc:creator>
<dc:date>2026-03-27</dc:date>
<dc:identifier>doi:10.64898/2026.03.24.713825</dc:identifier>
<dc:title><![CDATA[Stabilized gp120-specific CD4 for next-generation HIV-1 inhibitors]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-27</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.27.714602v1?rss=1">
<title>
<![CDATA[
Inhibitory-modulatory coupling generates persistent activity during working memory 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.27.714602v1?rss=1</link>
<description><![CDATA[
Working memory requires the stable maintenance of neural representations across temporal gaps, yet the circuit mechanisms that generate and stabilize persistent activity remain unsolved. Prevailing models emphasize recurrent excitation as the principal substrate of persistence, but how inhibitory and modulatory interactions shape the stability of temporal dynamics is unclear. Here, using trace conditioning in Drosophila, a working memory-dependent form of associative learning, we identify reciprocal inhibition as a circuit mechanism for sustaining persistent activity. In trace conditioning, a "trace" interval separates the conditioned and unconditioned stimuli, requiring maintenance of a neural representation across the trace interval, to support learning. Combining virtual-reality behavior, targeted neurogenetic perturbations, in vivo two-photon calcium imaging, and real-time neurotransmitter measurements, we uncover a reciprocal inhibitory microcircuit within the ellipsoid body that is selectively engaged during trace, but not delay (overlapping CS-US), conditioning. During the trace interval, ER2/4m neurons exhibit sustained activity, while reciprocally connected ER3/4d neurons show progressively strengthened suppression, forming a dynamically stabilized inhibitory loop. Disrupting GABA synthesis or reception within this circuit abolishes persistent activity and impairs trace learning, demonstrating the causal requirement for reciprocal inhibition in working memory maintenance. We further show that glutamatergic and nitric oxide signaling enhance inhibitory efficacy during the trace interval. In vivo neurotransmitter imaging reveals temporally structured dynamics in which glutamatergic signaling precedes and amplifies sustained GABAergic inhibition, consistent with modulatory stabilization of circuit persistence. Together, these findings identify reciprocal inhibition, reinforced by modulatory signaling, as a core circuit mechanism for dynamically stabilizing persistent neural representations. Our results challenge excitation-centric models of working memory and establish inhibitory-modulatory loops as a fundamental substrate for maintaining memory traces across time.
]]></description>
<dc:creator>Heintschel, M. L.</dc:creator>
<dc:creator>Xu, J.</dc:creator>
<dc:creator>Grover, D.</dc:creator>
<dc:date>2026-03-28</dc:date>
<dc:identifier>doi:10.64898/2026.03.27.714602</dc:identifier>
<dc:title><![CDATA[Inhibitory-modulatory coupling generates persistent activity during working memory]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.30.715357v1?rss=1">
<title>
<![CDATA[
SIP-enabled multi-omics reveals soil microbiome responses to drought and rehydration 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.30.715357v1?rss=1</link>
<description><![CDATA[
The activity of the soil microbiome, and its balance of anabolic (organic C consuming) and catabolic (CO2-releasing) reactions, determines the magnitude and direction of soil carbon fluxes. Over half a century of research has revealed that soil water dynamics are key controllers of microbial activity. With increasing hydroclimate volatility expected across many regions of the Earth, there is a greater need to describe and quantify microbial responses to drought and rehydration cycles. In this study, we conducted rainfall exclusion experiments at two archetypical Mediterranean-type field sites. After rainfall exclusion and subsequent soil rehydration, we applied a SIP-enabled, multi-omics methodology to generate a multi-faceted case study of microbial growth, greenhouse gas fluxes, and the forms of carbon that drive both. Our results indicate that rehydration increases microbial anabolic processes by orders of magnitude, shifting cell generation times from years to days within just minutes. High-intensity drought increases the lag period before microbial growth resumes, but both stable-isotope probing and metagenomic inference agree that microbial communities exhibit greater capacity for rapid growth following drought stress. Furthermore, significant shifts in the soil metabolome are observed following drought and rehydration, implicating specific osmolytes as key to the microbial response and indicating metabolite diversity as a key modulator of microbiome functioning. Together, our results provide constraints on microbial activity rates in soil and mechanisms underpinning microbial responses to drought and rewetting. These findings motivate further research into microbial responses under increasingly volatile hydroclimate regimes and downstream contributions to the global carbon cycle.

Significance StatementSoil is a major global store and source of carbon. The microbiome determine the fate of soil organic carbon, and the microbiome is ultimately controlled by soil water dynamics. Early, innovative experiments by H.F. Birch defined "The Birch Effect" - the observation that soils emit CO2 following drying and subsequent rehydration. However, it remains unclear when, and to what magnitude, soil microorganisms are actively growing following this rehydration, and what biological mechanisms explain the observed CO2 pulse. In this work, we apply an array of methodologies to address this question, describing rates of microbial growth during drought and rewetting. Our results provide crucial insights into how soil microbiomes will respond to increasing hydroclimate volatility across the globe.
]]></description>
<dc:creator>Caro, T. A.</dc:creator>
<dc:creator>Arriaga, J. I.</dc:creator>
<dc:creator>Grossman, E.</dc:creator>
<dc:creator>Jhatro, A.</dc:creator>
<dc:creator>Stewart, B.</dc:creator>
<dc:creator>Sessions, A.</dc:creator>
<dc:creator>Karthikeyan, S.</dc:creator>
<dc:date>2026-03-31</dc:date>
<dc:identifier>doi:10.64898/2026.03.30.715357</dc:identifier>
<dc:title><![CDATA[SIP-enabled multi-omics reveals soil microbiome responses to drought and rehydration]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-03-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.03.30.714681v1?rss=1">
<title>
<![CDATA[
LBR nucleoplasmic domains regulate X-chromosome solubility and nuclear organization 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.03.30.714681v1?rss=1</link>
<description><![CDATA[
The nuclear lamina plays a central role in genome organization, yet how specific lamina-associated proteins regulate chromosome architecture during development remains unclear. Here, we show that the nucleoplasmic domains of the Lamin B Receptor (LBR) are essential for X-chromosome localization at the nuclear periphery and chromatin architecture during neural differentiation. Using genetic dissection of LBR function, combined with genome-wide chromatin solubility profiling and transcriptional analyses, we demonstrate that loss of LBR N-terminal domains impairs proper cell differentiation and X chromosome inactivation (XCI), selectively disrupting chromatin structure in neural progenitors but not in pluripotent cells. Strikingly, these effects are disproportionately concentrated - but not limited to - on the inactive X chromosome, which undergoes a pronounced shift toward a more soluble chromatin state. Our findings establish the nucleoplasmic function of LBR as a key determinant of X-chromosome functionality and identify chromatin solubility and accessibility as a previously underappreciated layer of genome regulation by the nuclear lamina in XCI. Finally, our work provides definitive genetic evidence that LBRs nuclear architectural functions are molecularly separable from its metabolic sterol reductase activity, which is preserved in our model, and are critically necessary for XCI in differentiating mouse female XX ESCs models.
]]></description>
<dc:creator>Fiorentino, J.</dc:creator>
<dc:creator>Perotti, I.</dc:creator>
<dc:creator>Blanes, N. R.</dc:creator>
<dc:creator>Rosti, V.</dc:creator>
<dc:creator>Sigala, I.</dc:creator>
<dc:creator>Nikolakaki, E.</dc:creator>
<dc:creator>Colantoni, A.</dc:creator>
<dc:creator>D'Elia, A.</dc:creator>
<dc:creator>Massari, R.</dc:creator>
<dc:creator>Scavizzi, F.</dc:creator>
<dc:creator>Raspa, M.</dc:creator>
<dc:creator>Ascolani, M.</dc:creator>
<dc:creator>Humphreys, N. E.</dc:creator>
<dc:creator>Giannakouros, T.</dc:creator>
<dc:creator>Guttman, M.</dc:creator>
<dc:creator>Lanzuolo, C.</dc:creator>
<dc:creator>Tartaglia, G. G.</dc:creator>
<dc:creator>Cerase, A.</dc:creator>
<dc:date>2026-04-01</dc:date>
<dc:identifier>doi:10.64898/2026.03.30.714681</dc:identifier>
<dc:title><![CDATA[LBR nucleoplasmic domains regulate X-chromosome solubility and nuclear organization]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-04-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.04.01.715963v1?rss=1">
<title>
<![CDATA[
TXNDC15 modulated quality control at the endoplasmic reticulum shapes ciliogenesis 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.04.01.715963v1?rss=1</link>
<description><![CDATA[
At the endoplasmic reticulum (ER), membrane protein quality control is tightly regulated to ensure excess subunits are recognized and degraded to protect cellular homeostasis. Using genome wide CRISPR screens, we identified a factor of unknown function, thioredoxin domain containing protein 15 (TXNDC15), and showed that it regulates membrane protein stability by tuning the activity of the E3-ubiquitin ligase, MARCHF6. TXNDC15 modulates MARCHF6 in two opposing ways: first, it enhances the binding, ubiquitination, and degradation of membrane protein subunits with soluble cytosolic domains; and second, it prevents the inappropriate recruitment and ubiquitination of subunits with globular lumenal domains. Patient mutations to TXNDC15 that cause the ciliopathy Meckel-Gruber syndrome, disrupted its binding to MARCHF6, allowing degradation of critical ciliary proteins as they transit through the ER leading to defects in ciliogenesis. The regulatory function of TXNDC15 therefore exemplifies how protein quality control maintains the integrity of the proteome to prevent disease.
]]></description>
<dc:creator>Nguyen, V. N.</dc:creator>
<dc:creator>Boegeholz, L. A. K.</dc:creator>
<dc:creator>Page, K. R.</dc:creator>
<dc:creator>Zhang, J.</dc:creator>
<dc:creator>Ernst, M.</dc:creator>
<dc:creator>Wang, T.-Y.</dc:creator>
<dc:creator>Chen, N.</dc:creator>
<dc:creator>Mayank, A.</dc:creator>
<dc:creator>Wang, M. L.</dc:creator>
<dc:creator>Wohlschlegel, J.</dc:creator>
<dc:creator>Chou, T.-F.</dc:creator>
<dc:creator>Guna, A.</dc:creator>
<dc:creator>Voorhees, R. M.</dc:creator>
<dc:date>2026-04-02</dc:date>
<dc:identifier>doi:10.64898/2026.04.01.715963</dc:identifier>
<dc:title><![CDATA[TXNDC15 modulated quality control at the endoplasmic reticulum shapes ciliogenesis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-04-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/content/10.64898/2026.04.02.716195v1?rss=1">
<title>
<![CDATA[
Hybrid crosses reveal a cell-type-specific landscape of mouse regulatory variation 
]]>
</title>
<link>https://biorxiv.org/content/10.64898/2026.04.02.716195v1?rss=1</link>
<description><![CDATA[
Understanding the genetic architecture of gene expression is fundamental to evolutionary biology and medicine. As part of the IGVF Consortium, we present a single-nucleus RNA-seq resource of 6.7 million nuclei across eight tissue groups, featuring seven F1 hybrids from C57BL/6J dams crossed with the other Collaborative Cross founder strains for comparison against parental strains. We identify 25,777 genes (91% of those detected) exhibiting non-conserved regulatory behavior in at least one of 92 cell types in one or more crosses. Our results show that while cis-acting variation primarily drives divergence, trans-acting effects are substantially more cell-type specific and sensitive to tissue environment. Notably, bulk tissue analyses frequently mask these signals, particularly in smaller populations such as astrocytes. Furthermore, increasing genetic divergence primarily expands the landscape of cis-acting variation, while trans-acting effects remain stable across genetic distances within species. This atlas establishes a foundational framework for decoding the complex interplay between genetic variation and cell-type-specific regulation across the mammalian body.
]]></description>
<dc:creator>Weber, R.</dc:creator>
<dc:creator>Carilli, M.</dc:creator>
<dc:creator>Rebboah, E.</dc:creator>
<dc:creator>Filimban, G.</dc:creator>
<dc:creator>Liang, H. Y.</dc:creator>
<dc:creator>Trout, D.</dc:creator>
<dc:creator>Duffield, M.</dc:creator>
<dc:creator>Mahdipoor, P.</dc:creator>
<dc:creator>Taghizadeh, E.</dc:creator>
<dc:creator>Fattahi, N.</dc:creator>
<dc:creator>Mojaverzargar, R.</dc:creator>
<dc:creator>Kawauchi, S.</dc:creator>
<dc:creator>Williams, B. A.</dc:creator>
<dc:creator>MacGregor, G.</dc:creator>
<dc:creator>Wold, B.</dc:creator>
<dc:creator>Pachter, L.</dc:creator>
<dc:creator>Hallgrimsdottir, I. B.</dc:creator>
<dc:creator>Mortazavi, A.</dc:creator>
<dc:date>2026-04-04</dc:date>
<dc:identifier>doi:10.64898/2026.04.02.716195</dc:identifier>
<dc:title><![CDATA[Hybrid crosses reveal a cell-type-specific landscape of mouse regulatory variation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-04-04</prism:publicationDate>
<prism:section></prism:section>
</item>
</rdf:RDF>
