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	<title>bioRxiv Channel: RNA Therapeutics Institute at UMass Chan Med School</title>
	<link>https://biorxiv.org</link>
	<description>
	This feed contains articles for bioRxiv Channel "RNA Therapeutics Institute at UMass Chan Med School"
	</description>

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		</rdf:Seq>
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	<prism:publicationName>bioRxiv</prism:publicationName>
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	<title>bioRxiv</title>
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	<link>https://biorxiv.org</link>
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	<item rdf:about="https://biorxiv.org/cgi/content/short/2025.11.25.690450v1?rss=1">
<title>
<![CDATA[
In extracto cryo-EM reveals eEF2 as a major hibernation factor on 60S and 80S particles 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.11.25.690450v1?rss=1"
</link>
<description><![CDATA[
Cryogenic electron microscopy (cryo-EM) made impressive progress in resolving cellular macromolecules and their detailed interactions. Single-particle cryo-EM traditionally relies on purified macromolecules and lacks the complexity of cellular environments, whereas in situ cryo-EM or cryo-ET require extensive sample preparation and data acquisition, presenting challenges in achieving high resolution. We describe cryo-EM of cellular lysates--in extracto cryo-EM--allowing the flexibility and high-resolution of cryo-EM in the context of cellular components. High-resolution 2D template matching (2DTM) yields [~]2.2 [A] maps of the mammalian translational apparatus. Elongating ribosome abundances in primate cell lines (MCF-7 and BSC-1) and rabbit reticulocyte lysates range from [~]70% to [~]10%, reflecting translational stress responses. Non-translating (hibernating) ribosomes carrying no mRNA, feature numerous proteins shielding ribosomal functional centers. Elongation factor 2 (eEF2) is the most abundant hibernation factor bound to >95% of ribosomes and, unexpectedly, to 60S subunits. eEF2*GDP is stabilized by interactions with the sarcin-ricin loop and protein uL14. Hibernating ribosomes also feature LARP1 involved in initiation and mTOR signaling; eIF5A implicated in elongation and termination; and other factors, exposing the variety of hibernation scenarios. Our work underscores the efficiency and potential of in extracto cryo-EM to discover native cellular complexes and mechanisms at near-atomic resolution.
]]></description>
<dc:creator>Seraj, Z.</dc:creator>
<dc:creator>Zottig, X.</dc:creator>
<dc:creator>Huang, C.</dc:creator>
<dc:creator>Loveland, A. B.</dc:creator>
<dc:creator>Diggs, S.</dc:creator>
<dc:creator>Sholi, E.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:creator>Korostelev, A. A.</dc:creator>
<dc:date>2025-11-25</dc:date>
<dc:identifier>doi:10.1101/2025.11.25.690450</dc:identifier>
<dc:title><![CDATA[In extracto cryo-EM reveals eEF2 as a major hibernation factor on 60S and 80S particles]]></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/cgi/content/short/2026.02.09.704866v1?rss=1">
<title>
<![CDATA[
High-throughput quantification of huntingtin mRNA expression and aggregation in mouse brain using automated RNAscope imaging. 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2026.02.09.704866v1?rss=1"
</link>
<description><![CDATA[
Huntingtons disease (HD) is a repeat-associated neurodegenerative disorder traditionally characterized by toxic protein pathology resulting from expanded CAG repeats in the huntingtin (HTT) gene. In recent years, however, studies have identified repeat expansion-driven RNA pathology as an additional and potentially independent contributor to disease. In particular, mutant HTT transcripts containing expanded CAG repeats accumulate in the nucleus and form discrete RNA clusters, a feature shared with several other repeat-associated disorders. While protein aggregation and its downstream consequences have been extensively studied, our current understanding of the composition, organization, and dynamics of these nuclear mRNA clusters remains limited. Progress in this area has been constrained in part by the lack of robust methods to detect and quantify expanded HTT transcripts at single-molecule resolution within intact tissue. As a result, the contribution of RNA clustering to disease mechanisms, its relationship to repeat length, and its interaction with other pathological features of HD remain poorly defined. Here we present a high-throughput RNAscope pipeline that combines automated confocal imaging with rigorous microscope characterization to quantify both single mRNA molecules and multi-transcript clusters in fixed mouse brain tissue. Using 3D Gaussian point-spread function (PSF) fitting calibrated on 200 nm fluorescent beads and pointilistic image features from tissue data, we establish per-slide intensity thresholds from negative controls and normalize experimental signals to single-molecule reference intensities. The critical validation of our approach operates at two scales: for single molecules, the linear relationship between spot size and intensity (r2 > 0.90) reflects variable probe binding along transcripts; for clusters, the linear scaling between cluster volume and mRNA content (R2 > 0.98) confirms uniform probe accessibility and enables quantitative conversion of fluorescence intensity to absolute mRNA counts. Applied to HttQ111+/- knock-in mice across multiple ages, we analyzed thousands of fields of view (FOVs), detecting >900,000 single mRNA molecules and segmenting >1.9 million mRNA clusters using two probes targeting mouse huntingtin (Htt): one detecting the spliced transcript that uses early cryptic polyadenylation sites in intron 1 (HTT1a), and one detecting full-length Htt (fl-HTT). Our analysis reveals considerable heterogeneity in mRNA accumulation: 16-63% of Q111 FOVs are classified as "extreme" (exceeding the 95th percentile of wildtype clustered mRNA levels), with striatum showing higher prevalence than cortex for both probes (HTT1a: 63% striatum, 31% cortex; fl-HTT: 44% striatum, 16%cortex). Extreme FOVs are characterized by elevated cluster numbers (2-6x more clusters per nucleus) and higher cluster density (1.3-1.7x more mRNA per {micro}m3). Cluster localization shows nuclear bias ([~]68%) in normal FOVs, but extreme FOVs exhibit a shift toward cytoplasmic localization, particularly for fl-HTT (48% nuclear vs 68% in normal FOVs), though the interpretation of this shift requires further investigation. Despite the large dataset at the cellular level, our study included only 11 mice (9 Q111, 2 wildtype), and this limited sample size precluded robust statistical inference at the animal level. Nevertheless, these quantitative metrics provide a framework for investigating disease mechanisms and evaluating therapeutic interventions using RNAscope in future studies with larger cohorts.
]]></description>
<dc:creator>van Velde, P.</dc:creator>
<dc:creator>Tran, B.</dc:creator>
<dc:creator>Allen, S.</dc:creator>
<dc:creator>Luu, E.</dc:creator>
<dc:creator>Furgal, R.</dc:creator>
<dc:creator>Summers, A.</dc:creator>
<dc:creator>Belgrad, J.</dc:creator>
<dc:creator>Knox, E.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Grunwald, D.</dc:creator>
<dc:date>2026-02-11</dc:date>
<dc:identifier>doi:10.64898/2026.02.09.704866</dc:identifier>
<dc:title><![CDATA[High-throughput quantification of huntingtin mRNA expression and aggregation in mouse brain using automated RNAscope imaging.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-02-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.04.24.591037v1?rss=1">
<title>
<![CDATA[
Cryo-EM Structure of HRSL Domain Reveals Activating Crossed Helices at the Core of GCN2 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.04.24.591037v1?rss=1"
</link>
<description><![CDATA[
GCN2 is a conserved receptor kinase activating the Integrated Stress Response (ISR) in eukaryotic cells. The ISR kinases detect accumulation of stress molecules and reprogram translation from basal tasks to preferred production of cytoprotective proteins. GCN2 stands out evolutionarily among all protein kinases due to the presence of a histidyl tRNA synthetase-like (HRSL) domain, which arises only in GCN2 and is located next to the kinase domain. How HRSL contributes to GCN2 signaling remains unknown. Here we report a 3.2 [A] cryo-EM structure of HRSL from thermotolerant yeast Kluyveromyces marxianus. This structure shows a constitutive symmetrical homodimer featuring a compact helical-bundle structure at the junction between HRSL and kinase domains, in the core of the receptor. Mutagenesis demonstrates that this junction structure activates GCN2 and indicates that our cryo-EM structure captures the active signaling state of HRSL. Based on these results, we put forward a GCN2 regulation mechanism, where HRSL drives the formation of activated kinase dimers. Remaining domains of GCN2 have the opposite role and in the absence of stress they help keep GCN2 basally inactive. This autoinhibitory activity is relieved upon stress ligand binding. We propose that the opposing action of HRSL and additional GCN2 domains thus yields a regulated ISR receptor.

Significance statementRegulation of protein synthesis (translation) is a central mechanism by which eukaryotic cells adapt to stressful conditions. In starving cells, this translational adaptation is achieved via the receptor kinase GCN2, which stays inactive under normal conditions, but is switched on under stress. The molecular mechanism of GCN2 switching is not well understood due to the presence of a structurally and biochemically uncharacterized histidyl tRNA synthetase-like domain (HRSL) at the core of GCN2. Here we use single-particle cryo-EM and biochemistry to elucidate the structure and function of HRSL. We identify a structure at the kinase/HRSL interface, which forms crossed helices and helps position GCN2 kinase domains for activation. These data clarify the molecular mechanism of GCN2 regulation.
]]></description>
<dc:creator>Solorio - Kirpichyan, K.</dc:creator>
<dc:creator>Golovenko, D.</dc:creator>
<dc:creator>Korostelev, A.</dc:creator>
<dc:creator>Yan, N.</dc:creator>
<dc:creator>Korennykh, A.</dc:creator>
<dc:date>2024-04-25</dc:date>
<dc:identifier>doi:10.1101/2024.04.24.591037</dc:identifier>
<dc:title><![CDATA[Cryo-EM Structure of HRSL Domain Reveals Activating Crossed Helices at the Core of GCN2]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-04-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.04.24.590997v1?rss=1">
<title>
<![CDATA[
mRNA nuclear clustering leads to a difference in mutant huntingtin mRNA and protein silencing by siRNAs in vivo 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.04.24.590997v1?rss=1"
</link>
<description><![CDATA[
Huntingtons disease (HD) is an autosomal dominant neurodegenerative disease caused by CAG repeat expansion in the first exon of the huntingtin gene (HTT). Oligonucleotide therapeutics, such as short interfering RNA (siRNA), reduce levels of huntingtin mRNA and protein in vivo and are considered a viable therapeutic strategy. However, the extent to which they silence HTT mRNA in the nucleus is not established. We synthesized siRNA cross-reactive to mouse (wild-type) Htt and human (mutant) HTT in a di-valent scaffold and delivered to two mouse models of HD. In both models, di-valent siRNA sustained lowering of wild-type Htt, but not mutant HTT mRNA expression in striatum and cortex. Near-complete silencing of both mutant HTT protein and wild-type Htt protein was observed in both models. Subsequent fluorescent in situ hybridization (FISH) analysis shows that di-valent siRNA acts predominantly on cytoplasmic mutant HTT transcripts, leaving clustered mutant HTT transcripts in the nucleus largely intact in treated HD mouse brains. The observed differences between mRNA and protein levels, exaggerated in the case of extended repeats, might apply to other repeat-associated neurological disorders.
]]></description>
<dc:creator>Allen, S. J.</dc:creator>
<dc:creator>O'Reilly, D.</dc:creator>
<dc:creator>Miller, R.</dc:creator>
<dc:creator>Sapp, E.</dc:creator>
<dc:creator>Summers, A.</dc:creator>
<dc:creator>Paquette, J.</dc:creator>
<dc:creator>Moreno, D. E.</dc:creator>
<dc:creator>Bramato, B.</dc:creator>
<dc:creator>McHugh, N.</dc:creator>
<dc:creator>Yamada, K.</dc:creator>
<dc:creator>Aronin, N.</dc:creator>
<dc:creator>DiFiglia, M.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:date>2024-04-28</dc:date>
<dc:identifier>doi:10.1101/2024.04.24.590997</dc:identifier>
<dc:title><![CDATA[mRNA nuclear clustering leads to a difference in mutant huntingtin mRNA and protein silencing by siRNAs in vivo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-04-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.06.06.597639v1?rss=1">
<title>
<![CDATA[
Preventing acute neurotoxicity of CNS therapeutic oligonucleotides with the addition of Ca2+ and Mg2+ in the formulation 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.06.06.597639v1?rss=1"
</link>
<description><![CDATA[
Oligonucleotide therapeutics (ASOs and siRNAs) have been explored for modulation of gene expression in the central nervous system (CNS), with several drugs approved and many in clinical evaluation. Administration of highly concentrated oligonucleotides to the CNS can induce acute neurotoxicity. We demonstrate that delivery of concentrated oligonucleotides to the CSF in awake mice induces acute toxicity, observable within seconds of injection. Electroencephalography (EEG) and electromyography (EMG) in awake mice demonstrated seizures. Using ion chromatography, we show that siRNAs can tightly bind Ca2+ and Mg2+ up to molar equivalents of the phosphodiester (PO)/phosphorothioate (PS) bonds independently of the structure or phosphorothioate content. Optimization of the formulation by adding high concentrations (above biological levels) of divalent cations (Ca2+ alone, Mg2+ alone, or Ca2+ and Mg2+) prevents seizures with no impact on the distribution or efficacy of the oligonucleotide. The data here establishes the importance of adding Ca2+ and Mg2+ to the formulation for the safety of CNS administration of therapeutic oligonucleotides.
]]></description>
<dc:creator>Miller, R.</dc:creator>
<dc:creator>Paquette, J.</dc:creator>
<dc:creator>Barker, A.</dc:creator>
<dc:creator>Sapp, E.</dc:creator>
<dc:creator>McHugh, N.</dc:creator>
<dc:creator>Bramato, B.</dc:creator>
<dc:creator>Yamada, N.</dc:creator>
<dc:creator>Alterman, J.</dc:creator>
<dc:creator>Echeveria, D.</dc:creator>
<dc:creator>Yamada, K.</dc:creator>
<dc:creator>Watts, J. K.</dc:creator>
<dc:creator>Anaclet, C.</dc:creator>
<dc:creator>DiFiglia, M.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Aronin, N.</dc:creator>
<dc:date>2024-06-08</dc:date>
<dc:identifier>doi:10.1101/2024.06.06.597639</dc:identifier>
<dc:title><![CDATA[Preventing acute neurotoxicity of CNS therapeutic oligonucleotides with the addition of Ca2+ and Mg2+ in the formulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-06-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.06.20.599943v1?rss=1">
<title>
<![CDATA[
RNAi-mediated silencing of SOD1 profoundly extends survival and functional outcomes in ALS mice 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.06.20.599943v1?rss=1"
</link>
<description><![CDATA[
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative condition, with 20% of familial and 2-3% of sporadic cases linked to mutations in the cytosolic superoxide dismutase (SOD1) gene. Mutant SOD1 protein is toxic to motor neurons, making SOD1 gene lowering a promising approach, supported by preclinical data and the 2023 FDA approval of the GapmeR ASO targeting SOD1, tofersen. Despite the approval of an ASO and the optimism it brings to the field, the pharmacodynamics and pharmacokinetics of therapeutic SOD1 modulation can be improved. Here, we developed a chemically stabilized divalent siRNA scaffold (di-siRNA) that effectively suppresses SOD1 expression in vitro and in vivo. With optimized chemical modification, it achieves remarkable CNS tissue permeation and SOD1 silencing in vivo. Administered intraventricularly, di-siRNASOD1 extended survival in SOD1-G93A ALS mice, surpassing survival previously seen in these mice by ASO modalities, slowed disease progression, and prevented ALS neuropathology. These properties offer an improved therapeutic strategy for SOD1-mediated ALS and may extend to other dominantly inherited neurological disorders.

One sentence summarySilencing SOD1 with chemically optimized divalent siRNA profoundly extends the lifespan of G93A mice and prevents neurodegenerative biochemical and behavioral phenotypes.
]]></description>
<dc:creator>Weiss, A.</dc:creator>
<dc:creator>Gilbert, J. W.</dc:creator>
<dc:creator>Flores, I. V. R.</dc:creator>
<dc:creator>Belgrad, J.</dc:creator>
<dc:creator>Ferguson, C.</dc:creator>
<dc:creator>Dogan, E. O.</dc:creator>
<dc:creator>Wightman, N.</dc:creator>
<dc:creator>Mocarski, K.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Summers, A.</dc:creator>
<dc:creator>Bramato, B.</dc:creator>
<dc:creator>McHugh, N.</dc:creator>
<dc:creator>Furgal, R.</dc:creator>
<dc:creator>Yamada, N.</dc:creator>
<dc:creator>Cooper, D.</dc:creator>
<dc:creator>Monopoli, K.</dc:creator>
<dc:creator>Godinho, B. M. D. C.</dc:creator>
<dc:creator>Hassler, M. R.</dc:creator>
<dc:creator>Yamada, K.</dc:creator>
<dc:creator>Greer, P. L.</dc:creator>
<dc:creator>Henninger, N.</dc:creator>
<dc:creator>Brown, R. H.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:date>2024-06-25</dc:date>
<dc:identifier>doi:10.1101/2024.06.20.599943</dc:identifier>
<dc:title><![CDATA[RNAi-mediated silencing of SOD1 profoundly extends survival and functional outcomes in ALS mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-06-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.07.12.603173v1?rss=1">
<title>
<![CDATA[
PRC1.6 localizes on chromatin with the human silencing hub (HUSH) complex for promoter-specific silencing 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.07.12.603173v1?rss=1"
</link>
<description><![CDATA[
An obligate step in the life cycle of HIV-1 and other retroviruses is the establishment of the provirus in target cell chromosomes. Transcriptional regulation of proviruses is complex, and understanding the mechanisms underlying this regulation has ramifications for fundamental biology, human health, and gene therapy implementation. The three core components of the Human Silencing Hub (HUSH) complex, TASOR, MPHOSPH8 (MPP8), and PPHLN1 (Periphilin 1), were identified in forward genetic screens for host genes that repress provirus expression. Subsequent loss-of-function screens revealed accessory proteins that collaborate with the HUSH complex to silence proviruses in particular contexts. To identify proteins associated with a HUSH complex-repressed provirus in human cells, we developed a technique, Provirus Proximal Proteomics, based on proximity labeling with C-BERST (dCas9-APEX2 biotinylation at genomic elements by restricted spatial tagging). Our screen exploited a lentiviral reporter that is silenced by the HUSH complex in a manner that is independent of the integration site in chromatin. Our data reveal that proviruses silenced by the HUSH complex are associated with DNA repair, mRNA processing, and transcriptional silencing proteins, including L3MBTL2, a member of the non-canonical polycomb repressive complex 1.6 (PRC1.6). A forward genetic screen confirmed that PRC1.6 components L3MBTL2 and MGA contribute to HUSH complex-mediated silencing. PRC1.6 was then shown to silence HUSH-sensitive proviruses in a promoter-specific manner. Genome wide profiling showed striking colocalization of the PRC1.6 and HUSH complexes on chromatin, primarily at sites of active promoters. Finally, PRC1.6 binding at a subset of genes that are silenced by the HUSH complex was dependent on the core HUSH complex component MPP8. These studies offer new tools with great potential for studying the transcriptional regulation of proviruses and reveal crosstalk between the HUSH complex and PRC1.6.
]]></description>
<dc:creator>Rodriguez, T. C.</dc:creator>
<dc:creator>Yurkovetskiy, L.</dc:creator>
<dc:creator>Nagalekshmi, K.</dc:creator>
<dc:creator>Lam, C. H. O.</dc:creator>
<dc:creator>Jazbec, E.</dc:creator>
<dc:creator>Maitland, S. A.</dc:creator>
<dc:creator>Wolfe, S.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:creator>Luban, J.</dc:creator>
<dc:date>2024-07-12</dc:date>
<dc:identifier>doi:10.1101/2024.07.12.603173</dc:identifier>
<dc:title><![CDATA[PRC1.6 localizes on chromatin with the human silencing hub (HUSH) complex for promoter-specific silencing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.07.23.604154v1?rss=1">
<title>
<![CDATA[
Amortized template-matching of molecular conformations from cryo-electron microscopy images using simulation-based inference 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.07.23.604154v1?rss=1"
</link>
<description><![CDATA[
AO_SCPLOWBSTRACTC_SCPLOWBiomolecules undergo conformational changes to perform their function. Cryo-electron microscopy (cryo-EM) can capture snapshots of biomolecules in various conformations. However, these images are noisy and display the molecule in unknown orientations, making it difficult to separate conformational differences from differences due to noise or projection directions. Here, we introduce cryo-EM simulation-based inference (cryoSBI) to infer the conformations of biomolecules and the uncertainties associated with the inference from individual cryo-EM images. CryoSBI builds on simulation-based inference, a combination of physics-based simulations and probabilistic deep learning, allowing us to use Bayesian inference even when likelihoods are too expensive to calculate. We begin with an ensemble of conformations, which can be templates from molecular simulations or modelling, and use them as structural hypotheses. We train a neural network approximating the Bayesian posterior using simulated images from these templates, and then use it to accurately infer the conformations of biomolecules from experimental images. Training is only done once, and after that, it takes just a few milliseconds to make inference on an image, making cryoSBI suitable for arbitrarily large datasets. CryoSBI eliminates the need to estimate particle pose and imaging parameters, significantly enhancing the computational speed in comparison to explicit likelihood methods. We illustrate and benchmark cryoSBI on synthetic data and showcase its promise on experimental single-particle cryo-EM data.
]]></description>
<dc:creator>Dingeldein, L.</dc:creator>
<dc:creator>Silva-Sanchez, D.</dc:creator>
<dc:creator>Evans, L.</dc:creator>
<dc:creator>D'Imprima, E.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:creator>Covino, R.</dc:creator>
<dc:creator>Cossio, P.</dc:creator>
<dc:date>2024-07-24</dc:date>
<dc:identifier>doi:10.1101/2024.07.23.604154</dc:identifier>
<dc:title><![CDATA[Amortized template-matching of molecular conformations from cryo-electron microscopy images using simulation-based inference]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-07-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.09.05.611238v1?rss=1">
<title>
<![CDATA[
Next generation APOBEC3 inhibitors: Optimally designed for potency and nuclease stability 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.09.05.611238v1?rss=1"
</link>
<description><![CDATA[
APOBEC3 (or A3) enzymes have emerged as potential therapeutic targets due to their role in introducing heterogeneity in viruses and cancer, often leading to drug resistance. Inhibiting these enzymes has remained elusive as initial phosphodiester (PO) linked DNA based inhibitors lack stability and potency. We have enhanced both potency and nuclease stability, of 2'-deoxy-zebularine (dZ), substrate-based oligonucleotide inhibitors for two critical A3s: A3A and A3G. While replacing the phosphate backbone with phosphorothioate (PS) linkages increased nuclease stability, fully PS-modified inhibitors lost potency (1.4-3.7 fold) due to the structural constraints of the active site. For both enzymes, mixed PO/PS backbones enhanced potency (2.3-9.2 fold), while also vastly improving nuclease resistance. We also strategically introduced 2'-fluoro sugar modifications, creating the first nanomolar inhibitor of A3G-CTD2. With hairpin-structured inhibitors containing optimized PS patterns and LNA sugar modifications, we characterize the first single-digit nanomolar inhibitor targeting A3A. These extremely potent A3A inhibitors, were highly resistant to nuclease degradation in serum stability assays. Overall, our optimally designed A3 oligonucleotide inhibitors show improved potency and stability, compared to previous attempts to inhibit these critical enzymes, opening the door to realize the therapeutic potential of A3 inhibition.
]]></description>
<dc:creator>Hedger, A. K.</dc:creator>
<dc:creator>Myint, W.</dc:creator>
<dc:creator>Lee, J. M.</dc:creator>
<dc:creator>Suchenski-Loustaunau, D.</dc:creator>
<dc:creator>Balachandran, V.</dc:creator>
<dc:creator>Shaqra, A. M.</dc:creator>
<dc:creator>Kurt Yilmaz, N.</dc:creator>
<dc:creator>Watts, J.</dc:creator>
<dc:creator>Matsuo, H.</dc:creator>
<dc:creator>Schiffer, C. A.</dc:creator>
<dc:date>2024-09-06</dc:date>
<dc:identifier>doi:10.1101/2024.09.05.611238</dc:identifier>
<dc:title><![CDATA[Next generation APOBEC3 inhibitors: Optimally designed for potency and nuclease stability]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-09-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/582023v1?rss=1">
<title>
<![CDATA[
Allelopathic effect of Anogeissus pendula Edgew. and Grewia flavescens A.Juss on Desmodium species in Alwar district of Rajasthan 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/582023v1?rss=1"
</link>
<description><![CDATA[
The effect of leaf leachates of Anogeissus pendula Edgew. and Grewia flavescens A.Juss was evaluated on growth of the three species of Desmodium in Alwar district of Rajasthan (27{degrees}4 to 28{degrees}4 N and 76{degrees}7 to 77{degrees}13 E). Anogeissus pendula reduced the seed germination of Desmodium repandum from 85% in control to 43% at 2% concentration, Desmodium gangeticum from 80% in control to 50% at 6% concentration and Desmodium triflorum from 78% in control to 28% at 0.1% concentration of leaf leachates. Similarly, the leaf leachates of Grewia flavescens reduced the seed germination of Desmodium repandum from 85% in control to 40% at 2% concentration, Desmodium gangeticum from 80% in control to 50% even at 0.1% concentration and Desmodium triflorum from 78% in control to 21% at 0.5% concentration. The leaf leachates of both the species also reduced the elongation of radicle and plumule of three Desmodium species; however, the adverse effect of leaf leachate of Grewia flavescens was more severe than that of the other species. Among the three Desmodium species, the allelopathic effect of Grewia flavescens and Anogeissus pendula was more severe on Desmodium triflorum as compared to the other two species. It may be suggested that the population of three species of Desmodium is partly regualated by the allelopathic effect of Anogeissus pendula and Grewia flavescens in this tropical dry deciduous forest.
]]></description>
<dc:creator>Prasad, R.</dc:creator>
<dc:creator>Yadav, A. S.</dc:creator>
<dc:date>2019-03-20</dc:date>
<dc:identifier>doi:10.1101/582023</dc:identifier>
<dc:title><![CDATA[Allelopathic effect of Anogeissus pendula Edgew. and Grewia flavescens A.Juss on Desmodium species in Alwar district of Rajasthan]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.10.04.616663v1?rss=1">
<title>
<![CDATA[
Antisense oligonucleotide targeting pathogenic sense repeat RNA in C9ORF72 suppresses production of antisense-dependent dipeptide repeat proteins implicated in ALS/FTD 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.10.04.616663v1?rss=1"
</link>
<description><![CDATA[
A six nucleotide repeat expansion in intron-1 of the C9ORF72 gene is the most common genetic mutation affecting individuals with Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Bi-directional transcription of the repeat expansion generates sense and antisense repeat RNAs that can then be translated in all reading frames to produce six distinct dipeptide repeat (DPR) proteins with unique termini. The precise site of translation initiation of these proteins within the C9ORF72 repeat expansion remains elusive. We used CRISPR-Cas9 genome editing and steric-blocking antisense oligonucleotides (ASOs) to investigate the contribution of different AUG codons in the antisense repeat RNA to the production of DPR proteins, poly(GP) and poly(PR) in C9ORF72 expansion carrier motor neurons and lymphoblast cells. We then utilized ASOs targeting C9ORF72 sense repeat RNA to examine whether sense or antisense RNA is the major source of the poly(GP) protein - a question for which conflicting evidence exists. We found that these ASOs reduced the intended sense RNA target, but also the antisense RNA, thus preventing the production of poly(PR). Our data highlights the importance of the sequences preceding the antisense CCCCGG repeat expansion for the synthesis of antisense DPR proteins and supports the use of sense C9ORF72 ASOs to prevent the accumulation of both sense- and antisense-dependent DPR proteins in C9ORF72 ALS/FTD.
]]></description>
<dc:creator>Gu, Y.</dc:creator>
<dc:creator>Kankel, M. W.</dc:creator>
<dc:creator>Watts, J.</dc:creator>
<dc:creator>Jafar-nejad, P.</dc:creator>
<dc:creator>Almeida, S.</dc:creator>
<dc:date>2024-10-05</dc:date>
<dc:identifier>doi:10.1101/2024.10.04.616663</dc:identifier>
<dc:title><![CDATA[Antisense oligonucleotide targeting pathogenic sense repeat RNA in C9ORF72 suppresses production of antisense-dependent dipeptide repeat proteins implicated in ALS/FTD]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.10.15.618557v1?rss=1">
<title>
<![CDATA[
Virion-associated influenza hemagglutinin clusters upon sialic acid binding visualized by cryo-electron tomography 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.10.15.618557v1?rss=1"
</link>
<description><![CDATA[
Influenza viruses are enveloped, negative sense single-stranded RNA viruses covered in a dense layer of glycoproteins. Hemagglutinin (HA) accounts for 80-90% of influenza glycoprotein and plays a role in host cell binding and membrane fusion. While previous studies have characterized structures of receptor-free and receptor-bound HA in vitro, the effect of receptor binding on HA organization and structure on virions remains unknown. Here, we used cryo-electron tomography (cryoET) to visualize influenza virions bound to a sialic acid receptor mimic. Overall, receptor binding did not result in significant changes in viral morphology; however, we observed rearrangements of HA trimer organization and orientation. Compared to the even inter-glycoprotein spacing of unliganded HA trimers, receptor binding promotes HA trimer clustering and formation of a triplet of trimers. Subtomogram averaging and refinement yielded 8-10 [A] reconstructions that allowed us to visualize specific contacts between HAs from neighboring trimers and identify molecular features that mediate clustering. Taken together, we present new structural evidence that receptor binding triggers clustering of HA trimers, revealing an additional layer of HA dynamics and plasticity.
]]></description>
<dc:creator>Huang, Q. Y.</dc:creator>
<dc:creator>Kim, R.</dc:creator>
<dc:creator>Song, K.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:creator>Munro, J.</dc:creator>
<dc:creator>Schiffer, C. A.</dc:creator>
<dc:creator>Somasundaran, M.</dc:creator>
<dc:date>2024-10-18</dc:date>
<dc:identifier>doi:10.1101/2024.10.15.618557</dc:identifier>
<dc:title><![CDATA[Virion-associated influenza hemagglutinin clusters upon sialic acid binding visualized by cryo-electron tomography]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.11.02.621675v1?rss=1">
<title>
<![CDATA[
Mouse Pachytene piRNAs Cleave Hundreds of Transcripts,But Alter the Steady-State Abundance of Only a Minority of Targets 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.11.02.621675v1?rss=1"
</link>
<description><![CDATA[
In animals, 18-35-nt piRNAs guide PIWI proteins to regulate complementary RNAs. During male meiosis, mammals produce an exceptionally abundant class of piRNAs called pachytene piRNAs. Pachytene piRNAs are required for spermatogenesis and have been proposed to control gene expression by various mechanisms. Here, we show that pachytene piRNAs regulate targets predominantly, if not exclusively, by endonucleolytic cleavage. Remarkably, pachytene piRNAs slice hundreds of RNAs, yet a change in steady-state level is detectable for a small fraction of transcripts. Our data suggest that cleavage of the few targets whose abundance is reduced significantly by piRNAs is essential for male fertility. Other pachytene piRNA targets are enriched for highly transcribed genes, which may explain why piRNA cleavage is often inconsequential for the steady-state abundance of targets. We propose that the retention of pachytene piRNAs throughout mammalian evolution is driven by the selective advantage conferred by a tiny minority of piRNAs.
]]></description>
<dc:creator>Cecchini, K.</dc:creator>
<dc:creator>Ajaykumar, N.</dc:creator>
<dc:creator>Bagci, A.</dc:creator>
<dc:creator>Zamore, P.</dc:creator>
<dc:creator>Gainetdinov, I.</dc:creator>
<dc:date>2024-11-03</dc:date>
<dc:identifier>doi:10.1101/2024.11.02.621675</dc:identifier>
<dc:title><![CDATA[Mouse Pachytene piRNAs Cleave Hundreds of Transcripts,But Alter the Steady-State Abundance of Only a Minority of Targets]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.10.30.620986v1?rss=1">
<title>
<![CDATA[
Rational Design of Enhanced Nme2Cas9 and Nme2SmuCas9 Nucleases and Base Editors 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.10.30.620986v1?rss=1"
</link>
<description><![CDATA[
CRISPR-Cas genome editing tools enable precise, RNA-guided modification of genomes within living cells. The most clinically advanced genome editors are Cas9 nucleases, but many nuclease technologies provide only limited control over genome editing outcomes. Adenine base editors (ABEs) and cytosine base editors (CBEs) enable precise and efficient nucleotide conversions of A:T-to-G:C and C:G-to-T:A base pairs, respectively. Therapeutic use of base editors (BEs) provides an avenue to correct approximately 30% of human pathogenic variants. Nonetheless, factors such as protospacer adjacent motif (PAM) availability, accuracy, product purity, and delivery limit the full therapeutic potential of BEs. We previously developed Nme2Cas9 and its BE derivatives, including ABEs compatible with single adeno-associated virus (AAV) vector delivery, in part to enable editing near N4CC PAMs. Further engineering yielded domain-inlaid BEs with enhanced activity, as well as Nme2Cas9/SmuCas9 chimeras that target single-cytidine (N4C) PAMs. Here we further enhance Nme2Cas9 and Nme2SmuCas9 editing effectors for improved efficiency and vector compatibility through site-directed mutagenesis and deaminase linker optimization. Finally, we define the editing and specificity profiles of the resulting variants by using paired guide-target libraries.
]]></description>
<dc:creator>Bamidele, N.</dc:creator>
<dc:creator>Andosoria, A.</dc:creator>
<dc:creator>Chen, Z.</dc:creator>
<dc:creator>Cheng, H.</dc:creator>
<dc:creator>Panwala, R.</dc:creator>
<dc:creator>Jazbec, E.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:date>2024-10-30</dc:date>
<dc:identifier>doi:10.1101/2024.10.30.620986</dc:identifier>
<dc:title><![CDATA[Rational Design of Enhanced Nme2Cas9 and Nme2SmuCas9 Nucleases and Base Editors]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-10-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.11.16.623909v1?rss=1">
<title>
<![CDATA[
Dynamic cytoplasmic fluidity during morphogenesis in a human fungal pathogen 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.11.16.623909v1?rss=1"
</link>
<description><![CDATA[
The molecular crowding of the cytoplasm impacts a range of cellular processes. Using a fluorescent microrheological probe (GEMs), we observed a striking decrease in molecular crowding during the yeast to filamentous growth transition in the human fungal pathogen Candida albicans. This decrease in crowding is due to a decrease in ribosome concentration that results in part from an inhibition of ribosome biogenesis, combined with an increase in cytoplasmic volume; leading to a dilution of the major cytoplasmic crowder. Moreover, our results suggest that inhibition of ribosome biogenesis is a trigger for C. albicans morphogenesis.
]]></description>
<dc:creator>Serrano, A.</dc:creator>
<dc:creator>Puerner, C.</dc:creator>
<dc:creator>Plumb, E.</dc:creator>
<dc:creator>Chevalier, L.</dc:creator>
<dc:creator>Elferich, J.</dc:creator>
<dc:creator>Sinn, L. R.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:creator>Ralser, M.</dc:creator>
<dc:creator>Delarue, M.</dc:creator>
<dc:creator>Bassilana, M.</dc:creator>
<dc:creator>Arkowitz, R. A.</dc:creator>
<dc:date>2024-11-17</dc:date>
<dc:identifier>doi:10.1101/2024.11.16.623909</dc:identifier>
<dc:title><![CDATA[Dynamic cytoplasmic fluidity during morphogenesis in a human fungal pathogen]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-11-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.11.27.625707v1?rss=1">
<title>
<![CDATA[
Raver1 links Ripk1 RNA splicing to caspase-8-mediated pyroptotic cell death, inflammation, and pathogen resistance 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.11.27.625707v1?rss=1"
</link>
<description><![CDATA[
Multiple cell death and inflammatory signaling pathways converge on two critical factors: receptor interacting serine/threonine kinase 1 (RIPK1) and caspase-8. Careful regulation of these molecules is critical to control apoptosis, pyroptosis and inflammation. Here we discovered a pivotal role of Raver1 as an essential regulator of Ripk1 pre-mRNA splicing, expression, and functionality, and the subsequent caspase-8-dependent inflammatory cell death. Macrophages from Raver1-deficient mice exhibit altered splicing of Ripk1, accompanied by diminished cell death and reduced activation of caspase-8, Gasdermin D and E, caspase-1, as well as decreased interleukin-18 (IL-18) and IL-1{beta} production. These effects were triggered by Yersinia bacteria, or by restraining TAK1 or IKK{beta} in the presence of LPS, TNF family members, or IFN{gamma}. Consequently, animals lacking Raver1 showed heightened susceptibility to Yersinia infection. Raver1 and RIPK1 also controlled the expression and function of the C-type lectin receptor Mincle. Our study underscores the critical regulatory role of Raver1 in modulating innate immune responses and highlights its significance in directing in vivo and in vitro inflammatory processes.

SignificanceCaspase-8 and the kinase RIPK1 are at focal points of several inflammation and cell death pathways. Thus, a careful regulation of their actions is needed. Our work identifies the RNA splicing factor Raver1 as a critical factor directing the splicing of Ripk1 in order to modulate RIPK1/caspase-8-driven pyroptosis, apoptosis and inflammation. Raver1 is central for macrophage responses to Yersinia bacteria, initiated after blockade of kinases TAK1 and IKK, measured as activation of RIPK1, caspase-8, Gasdermin D, caspase-3, IL-1{beta} and IL-18. Importantly, Raver1 is necessary for host resistance to Yersinia infection in vivo. We propose that Raver1 is key for correct tuning of RIPK1-caspase-8 dependent processes.
]]></description>
<dc:creator>Zhang, B.</dc:creator>
<dc:creator>Orning, P.</dc:creator>
<dc:creator>Lehman, J. W.</dc:creator>
<dc:creator>Dinis, A.</dc:creator>
<dc:creator>Torres-Ulloa, L.</dc:creator>
<dc:creator>Elling, R.</dc:creator>
<dc:creator>Kelliher, M. A.</dc:creator>
<dc:creator>Bertin, J.</dc:creator>
<dc:creator>Proulx, M. K.</dc:creator>
<dc:creator>Ryan, L.</dc:creator>
<dc:creator>Kandasamy, R. K.</dc:creator>
<dc:creator>Espevik, T.</dc:creator>
<dc:creator>Pai, A. A.</dc:creator>
<dc:creator>Fitzgerald, K. A.</dc:creator>
<dc:creator>Lien, E.</dc:creator>
<dc:date>2024-11-29</dc:date>
<dc:identifier>doi:10.1101/2024.11.27.625707</dc:identifier>
<dc:title><![CDATA[Raver1 links Ripk1 RNA splicing to caspase-8-mediated pyroptotic cell death, inflammation, and pathogen resistance]]></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/cgi/content/short/2024.12.09.627542v1?rss=1">
<title>
<![CDATA[
Pol II degradation activates cell death independently from the loss of transcription 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.12.09.627542v1?rss=1"
</link>
<description><![CDATA[
Pol II-mediated transcription is essential for eukaryotic life. While loss of transcription is thought to be universally lethal, the associated mechanisms promoting cell death are not yet known. Here, we show that death following loss of Pol II is not caused by dysregulated gene expression. Instead, death occurs in response to the loss of Pol II protein itself, specifically loss of the enzymatic subunit, Rbp1. Loss of Pol II exclusively activates apoptosis, and expression of a transcriptionally inactive version of Rpb1 rescues cell viability. Using functional genomics, we identify a previously uncharacterized mechanism that regulates lethality following loss of Pol II, which we call the Pol II Degradation-dependent Apoptotic Response (PDAR). Using the genetic dependencies of PDAR, we identify clinically used drugs that owe their efficacy to a PDAR-dependent mechanism. Our findings unveil a novel apoptotic signaling response that contributes to the efficacy of a wide array of anti-cancer therapies.
]]></description>
<dc:creator>Harper, N. W.</dc:creator>
<dc:creator>Birdsall, G. A.</dc:creator>
<dc:creator>Honeywell, M. E.</dc:creator>
<dc:creator>Pai, A. A.</dc:creator>
<dc:creator>Lee, M. J.</dc:creator>
<dc:date>2024-12-10</dc:date>
<dc:identifier>doi:10.1101/2024.12.09.627542</dc:identifier>
<dc:title><![CDATA[Pol II degradation activates cell death independently from the loss of transcription]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-12-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.12.05.627039v1?rss=1">
<title>
<![CDATA[
Divalent siRNA for prion disease 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.12.05.627039v1?rss=1"
</link>
<description><![CDATA[
Prion protein (PrP) lowering is effective in animal models of prion disease and is being tested clinically in prion disease patients, but there remains a need for more potent PrP-lowering drug candidates. Inspired by the reported potency and duration of action of divalent short interfering RNA (siRNA), a new oligonucleotide drug modality for the central nervous system, we sought to discover and develop a new PrP-lowering drug candidate. Herein we identify a mouse Prnp-targeting divalent siRNA molecule, 1682-s4, that lowers PrP to 49% residual brain expression in wild-type mice, and, in the context of intracerebral infection with Rocky Mountain Laboratory (RML) prions, achieves a 2.7-fold increase in survival time with pre-symptomatic chronic treatment and 64% increase in survival time with a single dose after symptom onset. We describe the generation of two transgenic mouse lines, Tg25109 and Tg26372, expressing the full human PRNP gene and its non-coding sequence, and demonstrate their utility for in vivo discovery of potent human PRNP-targeting oligonucleotides. We discover siRNA sequence 2439 against human PRNP and compare its potency in different divalent siRNA chemical scaffolds. We determine that both the fixed UU tail and extended nucleic acid linkages of scaffold s4 contribute to superior potency compared to other scaffolds tested, offering 9.4 and 15.9 percentage points respectively of additional PrP knockdown. A single dose of 348 {micro}g of 2439-s4 lowered whole brain hemisphere human PrP in transgenic mice to 17% residual after 30 days, while 52 {micro}g lowered PrP to 49% residual. 1-2% of the dose of 2439-s4 delivered into cerebrospinal fluid is retained in the brain, and the median effective tissue concentration is estimated at 1.2 micrograms per gram of tissue. Good Laboratory Practices toxicology studies identified no significant liabilities, and the U.S. FDA has cleared an Investigational New Drug application to bring 2439-s4 into clinical trials.
]]></description>
<dc:creator>Gentile, J. E.</dc:creator>
<dc:creator>Corridon, T. L.</dc:creator>
<dc:creator>Serack, F. E.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Kennedy, Z. E.</dc:creator>
<dc:creator>Gallant-Behm, C. L.</dc:creator>
<dc:creator>Hassler, M. R.</dc:creator>
<dc:creator>Kinberger, G.</dc:creator>
<dc:creator>Kamath, N. G.</dc:creator>
<dc:creator>Lian, Y.</dc:creator>
<dc:creator>Gross, K. Y.</dc:creator>
<dc:creator>Miller, R.</dc:creator>
<dc:creator>DeSouza-Lenz, K.</dc:creator>
<dc:creator>Howard, M.</dc:creator>
<dc:creator>Guzman, K.</dc:creator>
<dc:creator>Chan, N.</dc:creator>
<dc:creator>Curtis, D. T.</dc:creator>
<dc:creator>Fettes, K.</dc:creator>
<dc:creator>Lemaitre, M.</dc:creator>
<dc:creator>Cappon, G.</dc:creator>
<dc:creator>Jackson, A. L.</dc:creator>
<dc:creator>Yamada, K.</dc:creator>
<dc:creator>Alterman, J. F.</dc:creator>
<dc:creator>Coffey, A. A.</dc:creator>
<dc:creator>Minikel, E. V.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Vallabh, S. M.</dc:creator>
<dc:date>2024-12-09</dc:date>
<dc:identifier>doi:10.1101/2024.12.05.627039</dc:identifier>
<dc:title><![CDATA[Divalent siRNA for prion disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-12-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.03.05.641556v1?rss=1">
<title>
<![CDATA[
Loss of the Integrator and Nuclear Exosome Targeting complexes disrupts oogenesis and causes the emergenceof atypical transcripts in Drosophila 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.03.05.641556v1?rss=1"
</link>
<description><![CDATA[
Nuclear RNA homeostasis depends on the balance of transcription, RNA processing, degradation, and transport between the nucleus and cytoplasm. RNA degradation directed by the Integrator, nuclear exosome targeting (NEXT), and nuclear exosome complexes controls the accumulation of aberrant nuclear RNA. Here, we report that Drosophila oogenesis requires the Integrator, NEXT, and nuclear exosome complexes. Depletion of Integrator, NEXT, or nuclear exosome components in Drosophila female germ cells causes infertility and accumulation of 3' extended snRNAs, promoter upstream transcripts (PROMPTs), and cryptic transcripts. Our data highlight the essential role of nuclear RNA degradation and processing in Drosophila oogenesis and provide a catalog of RNAs whose nuclear levels are regulated by these three complexes. We propose that Integrator, NEXT, and the nuclear exosome support oogenesis by ensuring that inappropriate transcription does not overwhelm the limited supply of proteins that bind, process, and traffic RNA.
]]></description>
<dc:creator>Lee, Y.</dc:creator>
<dc:creator>Biasini, A.</dc:creator>
<dc:creator>Tipping, C.</dc:creator>
<dc:creator>Hong, S. H.</dc:creator>
<dc:creator>Zamore, P.</dc:creator>
<dc:date>2025-03-11</dc:date>
<dc:identifier>doi:10.1101/2025.03.05.641556</dc:identifier>
<dc:title><![CDATA[Loss of the Integrator and Nuclear Exosome Targeting complexes disrupts oogenesis and causes the emergenceof atypical transcripts in Drosophila]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-03-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.03.29.646093v1?rss=1">
<title>
<![CDATA[
In-Situ High-Resolution Cryo-EM Reconstructions from CEMOVIS 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.03.29.646093v1?rss=1"
</link>
<description><![CDATA[
Cryo-electron microscopy can be used to image cells and tissue at high resolution. To ensure electron transparency, sample thickness must not exceed 500 nm. Focused-ion-beam (FIB) milling has become the standard method to prepare thin samples (lamellae), however, the material removed by the milling process is lost, the imageable area is usually limited to a few square microns, and the surface layers sustain damage from the ion beam. We have examined cryo-electron microscopy of vitreous sections (CEMOVIS), a preparation technique based on cutting thin sections with a knife, as an alternative to FIB-milling. CEMOVIS sections also sustain damage, including compression, shearing and cracks. However, samples can be sectioned in series, producing many orders of magnitude more imageable area compared to lamellae making CEMOVIS an alternative to FIB-milling with distinct advantages. Using 2-dimensional template matching on images of CEMOVIS sections of Saccharomyces cerevisiae cells, we reconstructed the 60S ribosomal subunit at near-atomic resolution, demonstrating that, in many regions of the sections, the molecular structure of these subunits is largely intact, comparable to FIB-milled lamellae.
]]></description>
<dc:creator>Elferich, J.</dc:creator>
<dc:creator>Kaminek, M.</dc:creator>
<dc:creator>Kong, L.</dc:creator>
<dc:creator>Odriozola, A.</dc:creator>
<dc:creator>Kukulski, W.</dc:creator>
<dc:creator>Zuber, B.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:date>2025-03-31</dc:date>
<dc:identifier>doi:10.1101/2025.03.29.646093</dc:identifier>
<dc:title><![CDATA[In-Situ High-Resolution Cryo-EM Reconstructions from CEMOVIS]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-03-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.04.30.651568v1?rss=1">
<title>
<![CDATA[
Piwi and piRNAs repress transcription of aberrant rRNA genes containing retrotransposon fragments 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.04.30.651568v1?rss=1"
</link>
<description><![CDATA[
The genomes of eukaryotes comprise clusters of repeated rRNA genes, including defective copies that are silenced by poorly understood mechanisms. In Drosophila melanogaster, many 28S rDNA genes contain insertions of R1 or R2 retrotransposons. R2 elements can only transcribe as part of the pre-rRNA and then excise by the R2 ribozyme. Some rRNA genes carry truncated insertions, creating defective rRNA from which the R2 sequence cannot be excised. Here, we report that in Drosophila ovaries, the nuclear protein Piwi loaded with PIWI-interacting RNA (piRNA) is required to repress transcription of rDNA units with extensively truncated R2 insertions (R2short). Without Piwi, R2short-rDNA generates stable aberrant 28S rRNA containing [~]200 nt of R2 sequence. These rRNAs are excluded from cytoplasmic ribosomes and instead accumulate within the nucleoli of germ cells, where they may disrupt nucleolar homeostasis. Overall, our results show the involvement of the piRNA pathway in quality control of ribosomal transcription.
]]></description>
<dc:creator>Fefelova, E. A.</dc:creator>
<dc:creator>Shatskikh, A. S.</dc:creator>
<dc:creator>Mikhaleva, E. A.</dc:creator>
<dc:creator>Abramov, Y. A.</dc:creator>
<dc:creator>Lavrov, S. A.</dc:creator>
<dc:creator>Pirogov, S. A.</dc:creator>
<dc:creator>Poltorachenko, V. A.</dc:creator>
<dc:creator>Ilin, A. A.</dc:creator>
<dc:creator>Zamore, P. D.</dc:creator>
<dc:creator>Klenov, M. S.</dc:creator>
<dc:date>2025-04-30</dc:date>
<dc:identifier>doi:10.1101/2025.04.30.651568</dc:identifier>
<dc:title><![CDATA[Piwi and piRNAs repress transcription of aberrant rRNA genes containing retrotransposon fragments]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-04-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.03.26.645328v1?rss=1">
<title>
<![CDATA[
Single-dose administration of therapeutic divalent siRNA targeting MECP2 prevents lethality for one year in an MECP2 duplication mouse model 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.03.26.645328v1?rss=1"
</link>
<description><![CDATA[
AbstractMECP2 duplication syndrome (MDS) is a rare X-linked neurodevelopmental disorder caused by duplications of the dosage-sensitive methyl-CpG-binding protein 2 (MECP2) gene. Developing effective therapies for MDS is particularly challenging due to the variability in MECP2 expression among patients and the potential risk of inducing Rett syndrome through excessive pharmacological intervention. Reducing dosage to optimize silencing levels often compromises durability and necessitates increased dosing frequency. We present here a series of fully chemically modified small interfering RNAs (siRNAs) designed for both isoform-selective and total MECP2 silencing. Among these, we identify six lead siRNA candidates across two distinct chemical scaffolds, achieving targeted total MECP2 expression reductions ranging from 25% to 75%, sustained for at least four months following a single administration. The efficacy and safety of human ortholog silencing were evaluated using two mouse models with distinct levels of human MECP2 transgene expression. In the severe duplication model, a single dose of the total isoform-silencing siRNA fully rescued early mortality and behavioral impairments. Additionally, we show that the isoform-selective targeting strategy may be safer in mild cases of MDS where exaggerated pharmacology may lead to Rett Syndrome. Overall, this study introduces a series of preclinical candidates with the capacity to address the varying levels of MECP2 duplication encountered in clinical settings. Furthermore, it establishes a target selection strategy that may be applied to other dosage-sensitive gene imbalances.

One Sentence SummaryTherapeutic siRNAs provide safe and durable modulation of MECP2 for the treatment of mild and severe MECP2 Duplication Syndrome.
]]></description>
<dc:creator>Hariharan, V. N.</dc:creator>
<dc:creator>Summers, A.</dc:creator>
<dc:creator>Caiazzi, J.</dc:creator>
<dc:creator>Hildebrand, S.</dc:creator>
<dc:creator>OReilly, D.</dc:creator>
<dc:creator>Tang, Q.</dc:creator>
<dc:creator>Kennedy, Z.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>McHugh, N.</dc:creator>
<dc:creator>Cooper, D.</dc:creator>
<dc:creator>Sousa, J.</dc:creator>
<dc:creator>Ferguson, C.</dc:creator>
<dc:creator>Clipperton-Allen, A.</dc:creator>
<dc:creator>Bogdanik, L.</dc:creator>
<dc:creator>Coenraads, M.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:date>2025-03-29</dc:date>
<dc:identifier>doi:10.1101/2025.03.26.645328</dc:identifier>
<dc:title><![CDATA[Single-dose administration of therapeutic divalent siRNA targeting MECP2 prevents lethality for one year in an MECP2 duplication mouse model]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-03-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.05.07.652636v1?rss=1">
<title>
<![CDATA[
A Compact Base Editor Rescues AATD-associated Liver and Lung Disease in Mouse Models 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.05.07.652636v1?rss=1"
</link>
<description><![CDATA[
Alpha-1 antitrypsin deficiency (AATD) is commonly caused by a G-to-A mutation in the SERPINA1 gene (the PiZ mutation). The mutant PiZ AAT protein is sequestered in hepatocytes, causing lung emphysema due to insufficient AAT protein to inhibit neutrophil elastase in the lung. Here we show that a compact adenine base editor (ABE) with an evolved Cas9 nickase derived from Neisseria meningitidis (eNme2.C) can be packaged in a single AAV and correct the PiZ mutation in mouse models of AATD. An all-in-one eNme2.C-TadA8e/guide 2 plasmid achieved approximately 20% on-target editing in PiZ reporter cells. TadA9e, which has a narrower editing window than TadA8e, reduced bystander editing without significantly affecting the on-target edit. In PiZ transgenic mice, eNme2.C-TadA9e AAV showed approximately 23% editing efficiency after 8 weeks and reduced liver disease burden in treated mice. In a new AAT-null;PiZ transgenic mouse model, ABE restored serum levels of AAT to beyond the 570 g/mL therapeutic level. Moreover, ABE treatment was able to significantly correct lung functions in AAT-null;PiZ animals with emphysema. This study demonstrates the feasibility of an eNme2.C-based ABE in a single AAV to treat both AATD-associated liver and lung disease.
]]></description>
<dc:creator>Gao, J.</dc:creator>
<dc:creator>Bamidele, N.</dc:creator>
<dc:creator>Pires-Ferreira, D.</dc:creator>
<dc:creator>Destefano, A.</dc:creator>
<dc:creator>Tang, Q.</dc:creator>
<dc:creator>Cao, Y.</dc:creator>
<dc:creator>Xie, J.</dc:creator>
<dc:creator>Gao, G.</dc:creator>
<dc:creator>Gruntman, A.</dc:creator>
<dc:creator>Sontheimer, E.</dc:creator>
<dc:creator>Flotte, T.</dc:creator>
<dc:creator>Xue, W. J.</dc:creator>
<dc:date>2025-05-09</dc:date>
<dc:identifier>doi:10.1101/2025.05.07.652636</dc:identifier>
<dc:title><![CDATA[A Compact Base Editor Rescues AATD-associated Liver and Lung Disease in Mouse Models]]></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/cgi/content/short/2024.12.31.630891v1?rss=1">
<title>
<![CDATA[
Detection of HTTex1p by western blot and immunostaining of HD human and mouse brain using neo-epitope antibody P90 highlights impact of CAG repeat expansion on its size, solubility, and response to MSH3 silencing 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.12.31.630891v1?rss=1"
</link>
<description><![CDATA[
HTT1a was identified in human and mouse Huntingtons disease brain as the pathogenic exon 1 mRNA generated from aberrant splicing between exon 1 and 2 of HTT that contributes to aggregate formation and neuronal dysfunction.1 Detection of the huntingtin exon 1 protein (HTT1a) has been accomplished with fluorescence-based reporter assays (Meso Scale Discovery, Homogeneous Time Resolved Fluorescence) and immunoprecipitation assays in Huntingtons disease knock-in mice but direct detection in homogenates by gel electrophoresis and western blot assay has been lacking. Subcellular fractions prepared from mouse and human Huntingtons disease brain were separated by gel electrophoresis and probed by western blot with neo-epitope monoclonal antibodies 1B12 and 11G2 directed to the C-terminal eight residues of HTT1a. In caudate putamen of an allelic series of 6 month old Huntingtons disease knock-in mice (Q50, Q80, Q111, Q140 and Q175) HTT1a migration was inversely correlated with CAG repeat length and appeared as a SDS soluble high molecular mass smear in Q111, Q140 and Q175 mice but weakly in Q80 and not in WT mice or Q50 indicating a CAG repeat size threshold for detecting HTT1a. HTT1a immunoreactivity diminished if 1B12 and 11G2 antibodies were preincubated with an eight amino acid peptide containing the C-terminus of HTT1a but not with unrelated peptide sequence. Migration of HTT1a and its high molecular mass smear changed with age in caudate putamen of Q111, Q175 and YAC128 mice. Treating Q111 mice with siRNA to MSH3, a modifier of CAG repeat expansion, significantly reduced levels of the high molecular mass smear indicating that the effects of curbing CAG repeat expansion were quantifiable. A prominent 56-60 kDa doublet detected by 1B12 and 11G2 antibodies in lysates from human Huntingtons disease brain was not blocked by preincubation with C-terminal HTT1a blocking peptide and also appeared in brains of Parkinsons disease patients. 1B12 and 11G2 antibodies did not immunoprecipitate HTT proteins from either Huntingtons disease mouse or human brain lysates using conditions that pulled down full length HTT with anti-HTT antibody 2B7. Altogether these data show that 11G2 and 1B12 antibodies can be used in western blot assays to track and quantify immunoreactive HTT1a levels, solubility, and subcellular localization in Huntingtons disease mouse brain.

Abbreviated SummarySapp et al., report that pathogenic exon 1 protein HTT1a is detected in brain of mouse models of Huntingtons disease by direct western blot assay using monoclonal antibodies 11G2 and 1B12. Lowering MSH3 mRNA in the caudate putamen to prevent CAG repeat expansion reduced levels of HTT1a.
]]></description>
<dc:creator>Sapp, E.</dc:creator>
<dc:creator>Boudi, A.</dc:creator>
<dc:creator>Iwanowicz, A.</dc:creator>
<dc:creator>Belgrad, J.</dc:creator>
<dc:creator>Miller, R.</dc:creator>
<dc:creator>O'Reilly, D.</dc:creator>
<dc:creator>Yamada, K.</dc:creator>
<dc:creator>Deng, Y.</dc:creator>
<dc:creator>Joni, M.</dc:creator>
<dc:creator>Li, X.</dc:creator>
<dc:creator>Kegel-Gleason, K.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Reiner, A.</dc:creator>
<dc:creator>Aronin, N.</dc:creator>
<dc:creator>DiFiglia, M.</dc:creator>
<dc:date>2025-01-01</dc:date>
<dc:identifier>doi:10.1101/2024.12.31.630891</dc:identifier>
<dc:title><![CDATA[Detection of HTTex1p by western blot and immunostaining of HD human and mouse brain using neo-epitope antibody P90 highlights impact of CAG repeat expansion on its size, solubility, and response to MSH3 silencing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-01-01</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.06.10.658804v1?rss=1">
<title>
<![CDATA[
Lowering the HTT1a transcript as an effective therapy for Huntingtons disease 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.06.10.658804v1?rss=1"
</link>
<description><![CDATA[
Lowering the levels of HTT transcripts has been a major focus of therapeutic development for Huntingtons disease (HD), but which transcript should be lowered? HD is caused by a CAG repeat expansion in exon 1 of the HTT gene, and the rate of somatic expansion of this CAG repeat throughout life is now known to drive the age of onset and rate of disease progression. As the CAG repeat expands, the extent to which the HTT mRNA is alternatively processed to generate the HTT1a transcript and highly aggregation-prone and pathogenic HTT1a protein increases. Several HTT-lowering modalities have entered clinical trials that either target both HTT and HTT1a together, or full-length HTT alone. We have developed siRNAs that target the Htt1a mouse transcript (634/486) and used these, together with a potent Htt-targeting siRNA (10150) to compare the efficacy of lowering either full-length Htt or Htt1a. zQ175 and wild-type mice were treated with 10150 or 634/486 alongside control groups at 2 months of age with treatment to 6 or 10 months, or at 6 months with treatment to 10 months. The siRNA potency and durability were most effective in the hippocampus. Whilst both strategies showed benefits, despite the greater potency of 10150, targeting Htt1a was more effective at delaying HTT aggregation and transcriptional dysregulation than targeting full-length Htt. These data support HTT-lowering strategies that are designed to target the HTT1a transcript, either alone, or together with lowering full-length HTT.

One Sentence SummaryLowering HTT1a transcript levels delays the onset of molecular and neuropathological phenotypes in a knock-in mouse model of Huntingtons disease.
]]></description>
<dc:creator>Papadopoulou, A. S.</dc:creator>
<dc:creator>Alterman, J.</dc:creator>
<dc:creator>Landles, C.</dc:creator>
<dc:creator>Smith, E. J.</dc:creator>
<dc:creator>Conroy, F.</dc:creator>
<dc:creator>Phillips, J.</dc:creator>
<dc:creator>Canibano-Pico, M.</dc:creator>
<dc:creator>Nita, I. M.</dc:creator>
<dc:creator>Osborne, G. F.</dc:creator>
<dc:creator>Iqbal, A.</dc:creator>
<dc:creator>Aldous, S. G.</dc:creator>
<dc:creator>Bondulich, M. K.</dc:creator>
<dc:creator>Gomez-Paredes, C.</dc:creator>
<dc:creator>Sathasivam, K.</dc:creator>
<dc:creator>O'Reilly, D.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Bobkov, K.</dc:creator>
<dc:creator>Greene, J. R.</dc:creator>
<dc:creator>Aronin, N.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Bates, G. P.</dc:creator>
<dc:date>2025-06-11</dc:date>
<dc:identifier>doi:10.1101/2025.06.10.658804</dc:identifier>
<dc:title><![CDATA[Lowering the HTT1a transcript as an effective therapy for Huntingtons disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.03.04.641478v1?rss=1">
<title>
<![CDATA[
A single amino acid variant in the variable region I of AAV capsid confers liver detargeting 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.03.04.641478v1?rss=1"
</link>
<description><![CDATA[
AAV capsid serotypes isolated from nature have been widely used in gene delivery and gene therapy. Recently, more than 1,000 distinct AAV capsids were identified from human clinical samples by high-throughput, long-read DNA sequencing. In this study, we tap into this broad natural biodiversity of AAV capsids to develop liver-tropic AAV capsids. We initially screened a subset of variants derived from AAV8 (n=159) for packaging efficiency. The high-yielding variants were subjected to a barcoded vector library screen in mice and ferrets for their ability to mediate liver gene transfer. Although no variant surpassed AAV8 for liver targeting, several exhibited a liver detargeting phenotype. Among these, we focused on the N271D variant (AAV8 VP1 numbering), located in the variable region I (VR-1), which has been previously implicated in influencing liver tropism. The liver detargeting phenotype of AAV8.N271D was confirmed by single vector administration in mice. Additionally, we grafted the N271D variant onto AAV9 and MyoAAV capsids (N270D by AAV9 VP1 numbering). The AAV9.N270D and MyoAAV.N270D vectors showed a similar liver-detargeting phenotype, although muscle targeting was moderately reduced. Although we did not identify any capsid variants that outperform AAV8 in liver transduction, this study reinforces the important role of VR-1 in modulating liver tropism and highlights the potential of engineering VR-1 residues to reduce liver gene transfer and associated toxicity observed in several gene therapy studies.
]]></description>
<dc:creator>Xing, R.</dc:creator>
<dc:creator>Xu, M.</dc:creator>
<dc:creator>Reil, D.</dc:creator>
<dc:creator>Destefano, A.</dc:creator>
<dc:creator>Cui, M.</dc:creator>
<dc:creator>Liu, N.</dc:creator>
<dc:creator>Liang, J.</dc:creator>
<dc:creator>Xu, G.</dc:creator>
<dc:creator>Luo, L.</dc:creator>
<dc:creator>Xu, M.</dc:creator>
<dc:creator>Zhang, F.</dc:creator>
<dc:creator>Tai, P. W.</dc:creator>
<dc:creator>Gruntman, A. M.</dc:creator>
<dc:creator>Flotte, T. R.</dc:creator>
<dc:creator>Gao, G.</dc:creator>
<dc:creator>Wang, D.</dc:creator>
<dc:date>2025-03-05</dc:date>
<dc:identifier>doi:10.1101/2025.03.04.641478</dc:identifier>
<dc:title><![CDATA[A single amino acid variant in the variable region I of AAV capsid confers liver detargeting]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-03-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.06.24.661398v1?rss=1">
<title>
<![CDATA[
Blocking somatic repeat expansion and lowering huntingtin via RNA interference synergize to prevent Huntingtons disease pathogenesis in mice 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.06.24.661398v1?rss=1"
</link>
<description><![CDATA[
Huntingtons disease (HD) is a progressive neurodegenerative disorder with no approved therapies. Two major molecular drivers--somatic expansion of inherited CAG repeats and toxic mutant HTT (mHTT) variants--lead to neuronal dysfunction. Despite multiple trials, HTT-lowering strategies have not shown meaningful clinical benefit. Using therapeutic divalent siRNAs, we assessed the long-term impact of silencing MSH3 (a key regulator of somatic expansion), HTT, or both. In Q111 HD mice (>110 CAGs), which exhibit robust expansion, mHTT inclusions, and transcriptional dysregulation by 12 months, long-term MSH3 silencing blocked expansion, reduced inclusions, and reversed gene expression changes. HTT silencing alone had limited effect, but combined MSH3/HTT targeting synergistically eliminated inclusions and restored transcriptomic profiles. Parallel treatment in wild-type mice showed no toxicity, supporting the safety of long-term intervention. These findings position somatic expansion as a promising therapeutic target and demonstrate the potential of RNAi-based co-silencing of MSH3 and HTT as a disease-modifying strategy for HD.
]]></description>
<dc:creator>Belgrad, J.</dc:creator>
<dc:creator>Summers, A.</dc:creator>
<dc:creator>Landles, C.</dc:creator>
<dc:creator>Greene, J. R.</dc:creator>
<dc:creator>Hildebrand, S.</dc:creator>
<dc:creator>Knox, E.</dc:creator>
<dc:creator>Sapp, E.</dc:creator>
<dc:creator>Yamada, N.</dc:creator>
<dc:creator>Furgal, R.</dc:creator>
<dc:creator>Miller, R.</dc:creator>
<dc:creator>Osborne, G. F.</dc:creator>
<dc:creator>Chase, K.</dc:creator>
<dc:creator>Luu, E.</dc:creator>
<dc:creator>Freedman, J.</dc:creator>
<dc:creator>Bramato, B.</dc:creator>
<dc:creator>McHugh, N.</dc:creator>
<dc:creator>Benoit, V.</dc:creator>
<dc:creator>OReilly, D.</dc:creator>
<dc:creator>Greer, P.</dc:creator>
<dc:creator>Bates, G. P.</dc:creator>
<dc:creator>Vogt, T. F.</dc:creator>
<dc:creator>Lee, R.</dc:creator>
<dc:creator>Howland, D.</dc:creator>
<dc:creator>DiFiglia, M.</dc:creator>
<dc:creator>Aronin, N.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:date>2025-06-25</dc:date>
<dc:identifier>doi:10.1101/2025.06.24.661398</dc:identifier>
<dc:title><![CDATA[Blocking somatic repeat expansion and lowering huntingtin via RNA interference synergize to prevent Huntingtons disease pathogenesis in mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-06-25</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.07.16.665169v1?rss=1">
<title>
<![CDATA[
Pervasive noise in human splice site selection 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.07.16.665169v1?rss=1"
</link>
<description><![CDATA[
RNA splicing has historically been thought to be highly efficient and accurate, with little opportunity for deviation from regulated alternative splicing decisions. This dogma has been challenged by recent observations that suggest that biological noise may contribute substantially to transcriptome diversity. However, quantitative understanding of stochastic variations in splicing is challenging because these transcripts are likely subject to rapid degradation. Here, we use ultra-deep sequencing across RNA compartments to track splicing intermediates in human cells and see abundant cryptic splicing associated with genomic features that promote splicing noise. We observe pervasive usage of low-fidelity splice sites, likely due to stochasticity in recruitment or binding of the spliceosome. These sites are most likely degraded in the nucleus rather than targeted by translation-dependent degradation processes, suggesting widespread surveillance and rapid quality control of non-productive RNA transcripts. Our findings provide unprecedented insights into the propensity for error in RNA processing mechanisms and the regulation of alternative splice sites across a gene.
]]></description>
<dc:creator>Khokhar, E. S.</dc:creator>
<dc:creator>Brokaw, K.</dc:creator>
<dc:creator>Kartje, Z. J.</dc:creator>
<dc:creator>Sanabria, V.</dc:creator>
<dc:creator>Javeed, N.</dc:creator>
<dc:creator>Kumar, A.</dc:creator>
<dc:creator>Watts, J. K.</dc:creator>
<dc:creator>Pai, A. A.</dc:creator>
<dc:date>2025-07-20</dc:date>
<dc:identifier>doi:10.1101/2025.07.16.665169</dc:identifier>
<dc:title><![CDATA[Pervasive noise in human splice site selection]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-07-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.07.18.665582v1?rss=1">
<title>
<![CDATA[
The Inaugural Flatiron Institute Cryo-EM Conformational Heterogeneity Challenge 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.07.18.665582v1?rss=1"
</link>
<description><![CDATA[
Despite the rise of single particle cryo-electron microscopy (cryo-EM) as a premier method for resolving macromolecular structures at atomic resolution, methods to address molecular heterogeneity in vitrified samples have yet to reach maturity. With an increasing number of new methods to analyze the multitude of heterogeneous states captured in single particle images, a systematic approach to validation in this field is needed. With this motivation, we issued a challenge to the community to analyze two cryo-EM particle image sets of thyroglobulin that exhibit continuous conformational heterogeneity. The first dataset was experimental and the second was generated with a simulator, allowing control over the distribution of molecular structures and enabled direct comparison between participants submissions and the ground truth molecular structures and distributions. Participants were asked to submit 80 volumes representing the heterogeneous ensemble and estimate their respective populations in the image sets provided. Participation of the research community in the challenge was strong, with submissions from nearly all developers of heterogeneity methods, resulting in 41 submissions across both datasets. Submissions qualitatively exceeded expectations, with the molecular motions identified by methods resembling both each other and the ground truth motion. However, quantitatively assessing these similarities was a challenge in and of itself. In the process of assessing the submissions, we developed several validation metrics, most of which require reference to the underlying ground truth volumes. However, we have also explored the use of metrics that do not necessarily reference ground truth. This is particularly apt for experimental datasets where ground truth is inaccessible. These approaches allowed us to assess the similarity and accuracy in volume quality, molecular motions, and conformational distribution of di!erent submissions. These metrics and the e!orts of all participants help chart a path forward for the improvements of heterogeneity methods for cryo-EM and for future challenges to validate these new methods as they continue to be developed by the community.
]]></description>
<dc:creator>Astore, M. A.</dc:creator>
<dc:creator>Woollard, G.</dc:creator>
<dc:creator>Silva-Sanchez, D.</dc:creator>
<dc:creator>Zhou, W.</dc:creator>
<dc:creator>Kopylov, M.</dc:creator>
<dc:creator>Dao Duc, K.</dc:creator>
<dc:creator>Lederman, R. R.</dc:creator>
<dc:creator>Li, Y.</dc:creator>
<dc:creator>Zhou, Y.</dc:creator>
<dc:creator>Yuan, J.</dc:creator>
<dc:creator>Ye, F.</dc:creator>
<dc:creator>Gu, Q.</dc:creator>
<dc:creator>Vuillemot, R.</dc:creator>
<dc:creator>Jonic, S.</dc:creator>
<dc:creator>Dang, L.</dc:creator>
<dc:creator>Ludtke, S. J.</dc:creator>
<dc:creator>Bridges, H.</dc:creator>
<dc:creator>Liu, S.</dc:creator>
<dc:creator>McLean, M.</dc:creator>
<dc:creator>Peretroukhin, V.</dc:creator>
<dc:creator>Schwab, J.</dc:creator>
<dc:creator>Cruz-Chu, E. R.</dc:creator>
<dc:creator>Schwander, P.</dc:creator>
<dc:creator>Gilles, M. A.</dc:creator>
<dc:creator>Singer, A.</dc:creator>
<dc:creator>Herreros, D.</dc:creator>
<dc:creator>Carazo, J. M.</dc:creator>
<dc:creator>Sorzano, C. O. S.</dc:creator>
<dc:creator>Feathers, J. R.</dc:creator>
<dc:creator>Zhong, E. D.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:creator>Cossio, P.</dc:creator>
<dc:creator>Hanson, S. M.</dc:creator>
<dc:date>2025-07-22</dc:date>
<dc:identifier>doi:10.1101/2025.07.18.665582</dc:identifier>
<dc:title><![CDATA[The Inaugural Flatiron Institute Cryo-EM Conformational Heterogeneity Challenge]]></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/cgi/content/short/2025.07.29.667434v1?rss=1">
<title>
<![CDATA[
Therapeutic delivery of albumin-binding siRNA targeting IRS2 to diverse cell types reduces mammary tumor growth 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.07.29.667434v1?rss=1"
</link>
<description><![CDATA[
Oligonucleotide therapeutics are a new class of drugs that enable robust and sustained modulation of gene expression. However, achieving efficient delivery of siRNAs to tumors is a challenge for therapy. Here, we demonstrate that fully chemically modified siRNAs conjugated with an albumin-binding dendrimer are efficiently delivered to both neoplastic and stromal/immune cells within primary TNBC mammary tumors. siRNAs were designed to selectively target IRS2, a signaling adaptor of insulin and insulin-like growth factor signaling that has been implicated in aggressive breast cancers. These siRNAs reduced Irs2 expression in tumor and stromal cells without causing hyperglycemia, resulting in reduced tumor growth that was associated with decreased vascularization and alterations in macrophage polarization and the expression of EMT proteins. This work demonstrates that siRNAs can be delivered to neoplastic and specific stromal populations in mammary tumors and that they can effectively and specifically silence a driver of aggressive breast cancer.
]]></description>
<dc:creator>Tocheny, C. M.</dc:creator>
<dc:creator>Buchwald, J. E.</dc:creator>
<dc:creator>Dahlke, C. D.</dc:creator>
<dc:creator>Fakih, H. H.</dc:creator>
<dc:creator>Morgan, J. S.</dc:creator>
<dc:creator>Summers, A.</dc:creator>
<dc:creator>Wisniewski, C. A.</dc:creator>
<dc:creator>Jackson, S. O.</dc:creator>
<dc:creator>Lee, J.-S.</dc:creator>
<dc:creator>Card, M.-A.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Peterson, C.</dc:creator>
<dc:creator>Mercurio, A. M.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Shaw, L. M.</dc:creator>
<dc:date>2025-08-01</dc:date>
<dc:identifier>doi:10.1101/2025.07.29.667434</dc:identifier>
<dc:title><![CDATA[Therapeutic delivery of albumin-binding siRNA targeting IRS2 to diverse cell types reduces mammary tumor growth]]></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/cgi/content/short/2025.09.05.674398v1?rss=1">
<title>
<![CDATA[
Unbend: Correction of local beam-induced sample motion in cryo-EM images using a 3D spline model 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.09.05.674398v1?rss=1"
</link>
<description><![CDATA[
The exposure of frozen biological samples to the high-energy electron beam in a cryo-electron microscope commonly leads to beam-induced sample motion and distortions. Previously, we described Unblur, which is part of our cisTEM software to correct for beam-induced motion based on the alignment of full frames in a movie collected during the beam exposure (Grant et al., 2015). However, Unblur cannot accommodate motion due to more localized sample bending and distortions. Here, we present Unbend, extending Unblur by incorporating local motion correction using a three-dimensional cubic spline model. The 3D spline model is constructed using cubic B-splines along the exposure time axis, and bicubic B-splines within movie frames. Unbend is integrated into our cisTEM software with a new local motion visualization panel within the cisTEM graphical user interface. We processed movie frames from various in-situ sample types, including whole cells, lamellae, and cell lysates, to analyze motion behavior across different specimen types. To quantify the improvement in high-resolution signal, we utilized the 2D template matching method, which operates independently of the motion correction process, to search large ribosomal subunits from the motion-corrected micrographs. Overall, the signal-to-noise ratio of detected particles improved by 3-8% across different samples compared with full-frame aligned micrographs, while the number of detected target particles increased by up to [~]300%. The total and Von Mises equivalent strain shows a deformation scale of less than 1% in most of the samples, confirming that our model induces minimal additional distortion. Furthermore, we processed micrograph montages to study motion patterns across an entire sample, revealing considerable variance in distortion scale within the same sample, suggesting a complex underlying mechanism.
]]></description>
<dc:creator>Kong, L.</dc:creator>
<dc:creator>Zottig, X.</dc:creator>
<dc:creator>Elferich, J.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:date>2025-09-06</dc:date>
<dc:identifier>doi:10.1101/2025.09.05.674398</dc:identifier>
<dc:title><![CDATA[Unbend: Correction of local beam-induced sample motion in cryo-EM images using a 3D spline model]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.09.11.675606v1?rss=1">
<title>
<![CDATA[
Improved cryo-EM reconstruction of sub-50 kDa complexes using 2D template matching 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.09.11.675606v1?rss=1"
</link>
<description><![CDATA[
Visualizing the structures of small proteins and complexes has been a longstanding challenge in single-particle cryo-EM. Some of these targets have been successfully resolved by binding to antibody fragments (Fabs) or fusing with external scaffolds to increase their size. Recent advances in conventional single-particle techniques have enabled the determination of an in-creasing number of structures smaller than 100 kDa, achieving resolutions relevant to drug research. Compared to X-ray crystallography, cryo-EM preserves the near-native states of biomolecules, can resolve structural heterogeneity, and has the potential to apply to a wide range of targets. In this work, we demonstrate that the alignment and reconstruction of small macromolecular complexes can be significantly improved using high-resolution structures as priors combined with 2D template matching. Using this method, we were able to reconstruct previously intractable targets under 50 kDa and improve the density of the ligand-binding sites in the reconstructions. We envision that this method will further lower the molecular weight limit of single-particle cryo-EM, enabling its application to important drug-binding complexes that are below 50 kDa.
]]></description>
<dc:creator>Zhang, K.</dc:creator>
<dc:creator>Grant, T.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:date>2025-09-16</dc:date>
<dc:identifier>doi:10.1101/2025.09.11.675606</dc:identifier>
<dc:title><![CDATA[Improved cryo-EM reconstruction of sub-50 kDa complexes using 2D template matching]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-09-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.09.26.678779v1?rss=1">
<title>
<![CDATA[
Structural mechanism of mRNA decoding by mammalian GTPase GTPBP1 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.09.26.678779v1?rss=1"
</link>
<description><![CDATA[
GTP-binding protein 1 (GTPBP1) is a widespread translational GTPase closely related to elongation factor eEF1A. The loss of GTPBP1 leads to errors in neuronal development in animals and is associated with neurodegenerative disorders in humans. Although linked to translation and quality control mechanisms, GTPBP1 functions remain largely obscure. Similarly to eEF1A, GTPBP1 delivers cognate aminoacyl-tRNA to the ribosomal A site in a GTP-dependent manner, but GTP hydrolysis is not followed by rapid peptide bond formation, and GTPBP1-mediated elongation is slow. To establish the basis for GTPBP1 function, we determined cryo-EM structures of 80S ribosomal complexes bound to GTPBP1*aa-tRNA with GTP or the non-hydrolysable analog GDPCP. They revealed that the unique GTPBP1 architecture, including the additional eIF1/IF3-like N-terminal domain and the shoulder-interacting H-loop in place of the 2 helix of canonical GTPases, is responsible for establishing GTPBP1-specific interactions with tRNA and the ribosome, leading to slow GTPBP1 dissociation after GTP hydrolysis and thus delayed tRNA accommodation. Slow dissociation correlates with an extended proofreading stage resulting in higher accuracy of GTPBP1-mediated decoding and potentially allows GTPBP1 to elicit its putative quality control functions. GTPBP1 visualization provides the foundation for mapping and elucidating GTPBP1 mutations associated with human diseases.
]]></description>
<dc:creator>Susorov, D.</dc:creator>
<dc:creator>Miscicka, A.</dc:creator>
<dc:creator>Golovenko, D.</dc:creator>
<dc:creator>Loveland, A. B.</dc:creator>
<dc:creator>Zinoviev, A.</dc:creator>
<dc:creator>Pestova, T. V.</dc:creator>
<dc:creator>Korostelev, A. A.</dc:creator>
<dc:date>2025-09-26</dc:date>
<dc:identifier>doi:10.1101/2025.09.26.678779</dc:identifier>
<dc:title><![CDATA[Structural mechanism of mRNA decoding by mammalian GTPase GTPBP1]]></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/cgi/content/short/2025.11.06.687082v1?rss=1">
<title>
<![CDATA[
SPARK: in silico simulations for benchmarking nascent RNA sequencing experiments 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.11.06.687082v1?rss=1"
</link>
<description><![CDATA[
Nascent RNA sequencing offers profound insights into transcriptional dynamics, yet there are substantial challenges to analyzing these data. The development of proper computational tools necessitates realistic benchmarking datasets that reflect biological variability and technical biases. We present simulated pre-mRNA and RNA kinetics (SPARK), a versatile in silico framework for generating reads across nascent RNA sequencing approaches. SPARK simulates the process of transcription -- allowing for variable elongation rates and pausing events -- and key experimental features. SPARK provides a comprehensive platform for computational development and benchmarking in nascent RNA genomics.
]]></description>
<dc:creator>Calvo-Roitberg, E.</dc:creator>
<dc:creator>Lehman, J. W.</dc:creator>
<dc:creator>Tam, E.</dc:creator>
<dc:creator>Elhajjajy, S.</dc:creator>
<dc:creator>Engelhardt, B. E.</dc:creator>
<dc:creator>Pai, A. A.</dc:creator>
<dc:date>2025-11-08</dc:date>
<dc:identifier>doi:10.1101/2025.11.06.687082</dc:identifier>
<dc:title><![CDATA[SPARK: in silico simulations for benchmarking nascent RNA sequencing experiments]]></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/cgi/content/short/2025.12.16.694641v1?rss=1">
<title>
<![CDATA[
Albumin-binding dendrimer-conjugated siRNA enables safe and effective gene silencing throughout the central nervous system 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.12.16.694641v1?rss=1"
</link>
<description><![CDATA[
Improving siRNA delivery to the central nervous system (CNS) is a major focus for treating the numerous debilitating neurological conditions which have a genetic basis. Here, we present an albumin-binding siRNA based on an amphiphilic dendrimer conjugate (D-siRNA). We demonstrate that D-siRNA achieves effective and homogeneous delivery throughout the CNS following administration into the cerebrospinal fluid (CSF). In mice, a single CSF administration of D-siRNA resulted in potent and durable gene silencing across various brain regions, with effects lasting six months without detectable toxicity. We validate its utility in larger rodents (rats) using intrathecal administration--a clinically relevant route--showing effective and broad delivery and robust silencing. Benchmarking against other clinically relevant siRNA delivery scaffolds revealed that D-siRNA provides comparable delivery and efficacy, with more efficient conversion of gross uptake to functional uptake. These findings support the use of albumin-binding conjugates for brain delivery, and position D-siRNA as a safe, effective, and durable platform for gene silencing in the CNS.
]]></description>
<dc:creator>Fakih, H.</dc:creator>
<dc:creator>Ohara, M.</dc:creator>
<dc:creator>Summers, A.</dc:creator>
<dc:creator>Sarli, S.</dc:creator>
<dc:creator>Kelly, K.</dc:creator>
<dc:creator>Maru, B.</dc:creator>
<dc:creator>Bramato, B.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Watts, J.</dc:creator>
<dc:date>2025-12-18</dc:date>
<dc:identifier>doi:10.64898/2025.12.16.694641</dc:identifier>
<dc:title><![CDATA[Albumin-binding dendrimer-conjugated siRNA enables safe and effective gene silencing throughout the central nervous system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-12-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2025.12.28.696766v1?rss=1">
<title>
<![CDATA[
Structural basis for non-AUG translation regulation by 5MPs 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.12.28.696766v1?rss=1"
</link>
<description><![CDATA[
The cellular proteome is regulated by translation initiation on AUG or non-canonical (non-AUG) start codons1-3. Non-AUG initiation remodels proteome during stress and is implicated in cancer and other diseases4-6. The eIF5-mimic proteins (5MPs) restrict non-AUG start codon usage and thereby reprogram proteoform expression from mRNAs with alternative start sites, such as the oncogenic c-Myc7-10. The mechanism by which 5MPs induce such translational reprogramming remains unknown. Here, using in extracto cryo-electron microscopy (cryo-EM) and biochemical assays, we report that translational repression by 5MP strongly depends on the sequence context near the AUG or non-AUG codons. Cryo-EM structures of 5MP-bound 48S pre-initiation complexes (PICs) from native cell extracts reveal that 5MP binds at the A site of the small ribosomal subunit, stabilizing an expanded open-head conformation of the PIC scanning along mRNA. The N-terminal region of 5MP blocks the A site, whereas the C-terminal domain docks at eIF2{beta} and the initiator tRNAMet outside the P site (i.e., Pout). These findings indicate that 5MP protein directly biases the initiating 48S complexes toward the open conformation, promoting mRNA scanning and inhibiting initiation at suboptimal start codons.
]]></description>
<dc:creator>Zottig, X.</dc:creator>
<dc:creator>Huang, C.-Y.</dc:creator>
<dc:creator>Seraj, Z.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:creator>Korostelev, A. A.</dc:creator>
<dc:date>2025-12-29</dc:date>
<dc:identifier>doi:10.64898/2025.12.28.696766</dc:identifier>
<dc:title><![CDATA[Structural basis for non-AUG translation regulation by 5MPs]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-12-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2026.01.26.701902v1?rss=1">
<title>
<![CDATA[
Systematic Identification of Germ Granule Proteins Reveals Specialized Roles in RNAi and Small RNA Inheritance 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2026.01.26.701902v1?rss=1"
</link>
<description><![CDATA[
Biomolecular condensates, such as germ granules, organize RNAi pathways critical for fertility and genome regulation. Yet, the protein composition and functional contributions of these condensates remain poorly defined. Here, we applied TurboID proximity labeling to the Caenorhabditis elegans germ granule protein SIMR-1, integrating mass spectrometry with genetic screening, CRISPR-based tagging, and small RNA sequencing. This systematic approach identified several previously uncharacterized germ granule proteins that contribute to fertility, germline immortality, exogenous RNAi, and transgenerational inheritance. Small RNA sequencing of 21 mutants revealed broad and class-specific defects in siRNA and miRNA biogenesis, with distinct factors associated with defects in WAGO-class 22G-RNAs, CSR-class 22G-RNAs, or histone-directed small RNAs. Among these, we identified PINT-1, a highly disordered protein that directly interacts with and is recruited to germ granules by the PIWI Argonaute PRG-1. PINT-1 is required for piRNA-dependent and -independent secondary siRNA biogenesis and germline development. Comparative genomics revealed that PINT-1 has co-evolved with PRG-1 across nematodes, with a conserved structured N-terminus and a rapidly diverging repeat-rich intrinsically disordered region. Together, our findings expand the germ granule proteome and reveal how distinct condensate components contribute to specialized functions within the small RNA pathways, while highlighting an evolutionarily co-adapted PIWI interactor critical for siRNA biogenesis.
]]></description>
<dc:creator>Chen, S.</dc:creator>
<dc:creator>Prescott, L. H.</dc:creator>
<dc:creator>Mello, C. C.</dc:creator>
<dc:creator>Phillips, C. M.</dc:creator>
<dc:date>2026-01-28</dc:date>
<dc:identifier>doi:10.64898/2026.01.26.701902</dc:identifier>
<dc:title><![CDATA[Systematic Identification of Germ Granule Proteins Reveals Specialized Roles in RNAi and Small RNA Inheritance]]></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/cgi/content/short/2025.11.08.687378v1?rss=1">
<title>
<![CDATA[
Control of gene output by intron RNA structure 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2025.11.08.687378v1?rss=1"
</link>
<description><![CDATA[
During mRNA biogenesis, RNA folding can promote or antagonize transcript processing. The effects of intron structure on mRNA and protein levels remain largely unexplored, although introns account for the bulk of nascent RNA. Here we systematically probe the effect of intron structure using massively parallel reporter assays. We show that base pairing modulates gene expression across orders of magnitude through inhibitory RNA structures at splice sites and at newly identified regions. Conversely, poor splicing of human {beta}-globin pre-mRNA could be improved by sequence alterations that reduce base pairing. For large libraries of RNA structures differing in stability, machine learning models could nearly fully explain observed gene output. Structure destabilizing mutations emerge rapidly under selective pressure. Thus, formation of RNA structures as dictated by intron sequence provides a simple, powerful means to adjust gene expression.
]]></description>
<dc:creator>Schärfen, L.</dc:creator>
<dc:creator>Bech, P.</dc:creator>
<dc:creator>Podszywałow-Bartnicka, P.</dc:creator>
<dc:creator>Neugebauer, K. M.</dc:creator>
<dc:date>2025-11-09</dc:date>
<dc:identifier>doi:10.1101/2025.11.08.687378</dc:identifier>
<dc:title><![CDATA[Control of gene output by intron RNA structure]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2025-11-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/091256v1?rss=1">
<title>
<![CDATA[
Mechanism of ribosome rescue by ArfA and RF2 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/091256v1?rss=1"
</link>
<description><![CDATA[
ArfA rescues ribosomes stalled on truncated mRNAs by recruiting the release factor RF2, which normally binds stop codons to catalyze peptide release. We report two 3.2-[A] resolution cryo-EM structures - determined from a single sample - of the 70S ribosome with ArfA*RF2 in the A site. In both states, the ArfA C-terminus occupies the mRNA tunnel downstream of the A site. One state contains a compact inactive RF2 conformation, hitherto unobserved in 70S termination complexes. Ordering of the ArfA N-terminus in the second state rearranges RF2 into an extended conformation that docks the catalytic GGQ motif into the peptidyl-transferase center. Our work thus reveals the structural dynamics of ribosome rescue. The structures demonstrate how ArfA "senses" the vacant mRNA tunnel and activates RF2 to mediate peptide release without a stop codon, allowing stalled ribosomes to be recycled.
]]></description>
<dc:creator>Demo, G.</dc:creator>
<dc:creator>Svidritskiy, E.</dc:creator>
<dc:creator>Madireddy, R.</dc:creator>
<dc:creator>Diaz-Avalos, R.</dc:creator>
<dc:creator>Grant, T.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:creator>Sousa, D.</dc:creator>
<dc:creator>Korostelev, A.</dc:creator>
<dc:date>2016-12-02</dc:date>
<dc:identifier>doi:10.1101/091256</dc:identifier>
<dc:title><![CDATA[Mechanism of ribosome rescue by ArfA and RF2]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2016-12-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/145110v1?rss=1">
<title>
<![CDATA[
Reconstructing Spatial Transport Distributions In The Nuclear Pore Complex From 2D Images -- How Reliable Is It? 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/145110v1?rss=1"
</link>
<description><![CDATA[
Imaging single molecules in living cells and reconstituted cell systems has resulted in a new understanding of the dynamics of nuclear pore complex functions over the last decade. It does, however, fall short on providing insights into the functional relationships between the pore and nucleocytoplasmic cargo in three-dimensional space. This limited ability is the result of insufficient resolution of optical microscopes along the optical axis and limited fluorescent signal due to the short timescales involved in nuclear transport (fractions of a second). To bypass current technological limitations, it was suggested that highly time-resolved 2D single molecule data could be interpreted as projected cargo locations and could subsequently be transformed into a spatial cargo distribution by assuming cylindrical symmetry 1. Such cargo distributions would provide valuable insights into the NPC-mediated transport in cells. This method, termed 3D-SPEED, has attracted large interest inside and beyond the nuclear pore field, but has also been sharply critiqued for a lack of critical evaluation. Here we present such an evaluation, testing the robustness, reconstruction quality and model-dependency.
]]></description>
<dc:creator>Tu, L.-C.</dc:creator>
<dc:creator>Huisman, M.</dc:creator>
<dc:creator>Chung, Y.-C.</dc:creator>
<dc:creator>Smith, C.</dc:creator>
<dc:creator>Grunwald, D.</dc:creator>
<dc:date>2017-06-02</dc:date>
<dc:identifier>doi:10.1101/145110</dc:identifier>
<dc:title><![CDATA[Reconstructing Spatial Transport Distributions In The Nuclear Pore Complex From 2D Images -- How Reliable Is It?]]></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/cgi/content/short/156091v1?rss=1">
<title>
<![CDATA[
Single-molecule FISH in Drosophila muscle reveals location dependent mRNA composition of megaRNPs 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/156091v1?rss=1"
</link>
<description><![CDATA[
Single-molecule fluorescence in-situ hybridization (smFISH) provides direct access to the spatial relationship between nucleic acids and specific subcellular locations. The ability to precisely localize a messenger RNA can reveal key information about its regulation. Although smFISH is well established in cell culture or thin sections, methods for its accurate application to tissues are lacking. The utility of smFISH in thick tissue sections must overcome several challenges, including probe penetration of fixed tissue, accessibility of target mRNAs for probe hybridization, high fluorescent background, spherical aberration along the optical axis, and image segmentation of organelles. Here we describe how we overcame these obstacles to study mRNA localization in Drosophila larval muscle samples that approach 50 m thickness. We use sample-specific optimization of smFISH, particle identification based on maximum likelihood testing, and 3-dimensional multiple-organelle segmentation. The latter allows using independent thresholds for different regions of interest within an image stack. Our approach therefore facilitates accurate measurement of mRNA location in thick tissues.
]]></description>
<dc:creator>Noma, A.</dc:creator>
<dc:creator>Smith, C. S.</dc:creator>
<dc:creator>Huisman, M.</dc:creator>
<dc:creator>Martin, R. M.</dc:creator>
<dc:creator>Moore, M. J.</dc:creator>
<dc:creator>Grunwald, D.</dc:creator>
<dc:date>2017-06-26</dc:date>
<dc:identifier>doi:10.1101/156091</dc:identifier>
<dc:title><![CDATA[Single-molecule FISH in Drosophila muscle reveals location dependent mRNA composition of megaRNPs]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-06-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/195966v1?rss=1">
<title>
<![CDATA[
CRISPR-Based DNA Imaging in Living Cells Reveals Cell Cycle-Dependent Chromosome Dynamics 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/195966v1?rss=1"
</link>
<description><![CDATA[
In contrast to the well-studied condensation and folding of chromosomes during mitosis, their dynamics in interphase are less understood. We developed a sensitive, multicolor system, CRISPR-Sirius, allowing the real-time tracking of the dynamics of chromosomal loci. We tracked loci kilobases to megabases apart and found significant variation in the inter-locus distances of each pair, indicating differing degrees of DNA contortion. We resolved two distinct modes of dynamics of loci: saltatory local movements as well as translational movements of the domain. The magnitude of both of these modes of movements increased from early to late G1, whereas the translational movements were reduced in early S. The local fluctuations decreased slightly in early S and more markedly in mid-late S. These newly observed movements and their cell cycle-dependence are indicative of a hitherto unrecognized compaction-relaxation dynamic of the chromosomal fiber operating concurrently with changes in the extent of observed genomic domain movements.nnIN BRIEFDistinct chromosome folding and dynamics during cell cycle progression were dissected by CRISPR-Sirius DNA imaging in living cells.nnHIGHLIGHTSO_LICRISPR-Sirius allows tracking of pairs of chromosomal loci having kilobase to megabase inter-locus distancesnC_LIO_LIPair-wise tracking of loci allows measurement of both local and domain dynamicsnC_LIO_LIChromosomal fiber relaxation is positively correlated with local dynamicsnC_LIO_LIGenomic region size contributes to local and domain movementsnC_LIO_LIDistinct chromosome dynamics were uncovered during cell cycle progression in interphasenC_LI
]]></description>
<dc:creator>Ma, H.</dc:creator>
<dc:creator>Tu, L.-C.</dc:creator>
<dc:creator>Naseri, A.</dc:creator>
<dc:creator>Chung, Y.-C.</dc:creator>
<dc:creator>Grunwald, D.</dc:creator>
<dc:creator>Zhang, S.</dc:creator>
<dc:creator>Pederson, T.</dc:creator>
<dc:date>2017-09-29</dc:date>
<dc:identifier>doi:10.1101/195966</dc:identifier>
<dc:title><![CDATA[CRISPR-Based DNA Imaging in Living Cells Reveals Cell Cycle-Dependent Chromosome Dynamics]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-09-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/185694v1?rss=1">
<title>
<![CDATA[
Pan-arthropod analysis reveals somatic piRNAs as an ancestral TE defence 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/185694v1?rss=1"
</link>
<description><![CDATA[
In animals, small RNA molecules termed PIWI-interacting RNAs (piRNAs) silence transposable elements (TEs), protecting the germline from genomic instability and mutation. piRNAs have been detected in the soma in a few animals, but these are believed to be specific adaptations of individual species. Here, we report that somatic piRNAs were likely present in the ancestral arthropod more than 500 million years ago. Analysis of 20 species across the arthropod phylum suggests that somatic piRNAs targeting TEs and mRNAs are common among arthropods. The presence of an RNA-dependent RNA polymerase in chelicerates (horseshoe crabs, spiders, scorpions) suggests that arthropods originally used a plant-like RNA interference mechanism to silence TEs. Our results call into question the view that the ancestral role of the piRNA pathway was to protect the germline and demonstrate that small RNA silencing pathways have been repurposed for both somatic and germline functions throughout arthropod evolution.
]]></description>
<dc:creator>Lewis, S. H.</dc:creator>
<dc:creator>Quarles, K. A.</dc:creator>
<dc:creator>Yang, Y.</dc:creator>
<dc:creator>Tanguy, M.</dc:creator>
<dc:creator>Frezal, L.</dc:creator>
<dc:creator>Smith, S. A.</dc:creator>
<dc:creator>Sharma, P. P.</dc:creator>
<dc:creator>Cordaux, R.</dc:creator>
<dc:creator>Gilbert, C.</dc:creator>
<dc:creator>Giraud, I.</dc:creator>
<dc:creator>Collins, D. H.</dc:creator>
<dc:creator>Zamore, P. D.</dc:creator>
<dc:creator>Miska, E. A.</dc:creator>
<dc:creator>Sarkies, P.</dc:creator>
<dc:creator>Jiggins, F. M.</dc:creator>
<dc:date>2017-09-07</dc:date>
<dc:identifier>doi:10.1101/185694</dc:identifier>
<dc:title><![CDATA[Pan-arthropod analysis reveals somatic piRNAs as an ancestral TE defence]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-09-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/204776v1?rss=1">
<title>
<![CDATA[
Fluorescence polarization control for on-off switching of single molecules at cryogenic temperatures 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/204776v1?rss=1"
</link>
<description><![CDATA[
Light microscopy allowing sub-diffraction limited resolution has been among the fastest developing techniques at the interface of biology, chemistry and physics. Intriguingly no theoretical limit exists on how far the underlying measurement uncertainty can be lowered. In particular data fusion of large amounts of images can reduce the measurement error to match the resolution of structural methods like cryo-electron microscopy. Fluorescence, although reliant on a reporter molecule and therefore not the first choice to obtain ultra resolution structures, brings highly specific labeling of molecules in a large assemble to the table and inherently allows the detection of multiple colors, which enable the interrogation of multiple molecular species at the same time in the same sample. Here we discuss the problems to be solved in the coming years to aim for higher resolution and describe what polarization depletion of fluorescence at cryogenic temperatures can contribute for fluorescence imaging of biological samples like whole cells.
]]></description>
<dc:creator>Hulleman, C.</dc:creator>
<dc:creator>Huisman, M.</dc:creator>
<dc:creator>Moerland, R.</dc:creator>
<dc:creator>Grunwald, D.</dc:creator>
<dc:creator>Stallinga, S.</dc:creator>
<dc:creator>Rieger, B.</dc:creator>
<dc:date>2017-10-17</dc:date>
<dc:identifier>doi:10.1101/204776</dc:identifier>
<dc:title><![CDATA[Fluorescence polarization control for on-off switching of single molecules at cryogenic temperatures]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-10-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/226837v1?rss=1">
<title>
<![CDATA[
Conformational control of translation termination on the 70S ribosome 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/226837v1?rss=1"
</link>
<description><![CDATA[
Translation termination ensures proper lengths of cellular proteins. During termination, release factor (RF) recognizes a stop codon and catalyzes peptide release. Conformational changes in RF are thought to underlie accurate translation termination. If true, the release factor should bind the A-site codon in inactive (compact) conformation(s), but structural studies of ribosome termination complexes have only captured RFs in an extended, active conformation. Here, we identify a hyper-accurate RF1 variant, and present crystal structures of 70S termination complexes that suggest a structural pathway for RF1 activation. In the presence of blasticidin S, the catalytic domain of RF1 is removed from the peptidyl-transferase center, whereas the codon-recognition domain is fully engaged in stop-codon recognition in the decoding center. RF1 codon recognition induces decoding-center rearrangements that precede accommodation of the catalytic domain. Our findings suggest how structural dynamics of RF1 and the ribosome coordinate stop-codon recognition with peptide release, ensuring accurate translation termination.
]]></description>
<dc:creator>Svidritskiy, E.</dc:creator>
<dc:creator>Korostelev, A. A.</dc:creator>
<dc:date>2017-11-29</dc:date>
<dc:identifier>doi:10.1101/226837</dc:identifier>
<dc:title><![CDATA[Conformational control of translation termination on the 70S ribosome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/251892v1?rss=1">
<title>
<![CDATA[
Elimination of PCR duplicates in RNA-seq and small RNA-seq using unique molecular identifiers 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/251892v1?rss=1"
</link>
<description><![CDATA[
RNA-seq and small RNA-seq are powerful, quantitative tools to study gene regulation and function. Common high-throughput sequencing methods rely on polymerase chain reaction (PCR) to expand the starting material, but not every molecule amplifies equally, causing some to be overrepresented. Unique molecular identifiers (UMIs) can be used to distinguish undesirable PCR duplicates derived from a single molecule and identical but biologically meaningful reads from different molecules. We have incorporated UMIs into RNA-seq and small RNA-seq protocols and developed tools to analyze the resulting data. Our UMIs contain stretches of random nucleotides whose lengths sufficiently capture diverse molecule species in both RNA-seq and small RNA-seq libraries generated from mouse testis. Our approach yields high-quality data while allowing unique tagging of all molecules in high-depth libraries. Using simulated and real datasets, we demonstrate that our methods increase the reproducibility of RNA-seq and small RNA-seq data. Notably, we find that the amount of starting material and sequencing depth, but not the number of PCR cycles, determine PCR duplicate frequency. Finally, we show that computational removal of PCR duplicates based only on their mapping coordinates introduces substantial bias into data analysis.
]]></description>
<dc:creator>Fu, Y.</dc:creator>
<dc:creator>Wu, P.-H.</dc:creator>
<dc:creator>Beane, T.</dc:creator>
<dc:creator>Zamore, P. D.</dc:creator>
<dc:creator>Weng, Z.</dc:creator>
<dc:date>2018-01-22</dc:date>
<dc:identifier>doi:10.1101/251892</dc:identifier>
<dc:title><![CDATA[Elimination of PCR duplicates in RNA-seq and small RNA-seq using unique molecular identifiers]]></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/cgi/content/short/171819v1?rss=1">
<title>
<![CDATA[
C-BERST: Defining subnuclear proteomic landscapes at genomic elements with dCas9-APEX2 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/171819v1?rss=1"
</link>
<description><![CDATA[
Mapping proteomic composition at distinct genomic loci and subnuclear landmarks in living cells has been a long-standing challenge. Here we report that dCas9-APEX2 Biotinylation at genomic Elements by Restricted Spatial Tagging (C-BERST) allows the rapid, unbiased mapping of proteomes near defined genomic loci, as demonstrated for telomeres and centromeres. By combining the spatially restricted enzymatic tagging enabled by APEX2 with programmable DNA targeting by dCas9, C-BERST has successfully identified nearly 50% of known telomere-associated factors and many known centromere-associated factors. We also identified and validated SLX4IP and RPA3 as telomeric factors, confirming C-BERSTs utility as a discovery platform. C-BERST enables the rapid, high-throughput identification of proteins associated with specific sequences, facilitating annotation of these factors and their roles in nuclear and chromosome biology.
]]></description>
<dc:creator>Gao, X. D.</dc:creator>
<dc:creator>Tu, L.-C.</dc:creator>
<dc:creator>Mir, A.</dc:creator>
<dc:creator>Dekker, J.</dc:creator>
<dc:creator>Shaffer, S. A.</dc:creator>
<dc:creator>Zhu, L. J.</dc:creator>
<dc:creator>Wolfe, S. A.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:date>2017-08-02</dc:date>
<dc:identifier>doi:10.1101/171819</dc:identifier>
<dc:title><![CDATA[C-BERST: Defining subnuclear proteomic landscapes at genomic elements with dCas9-APEX2]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-08-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/262113v1?rss=1">
<title>
<![CDATA[
Identification of piRNA binding sites reveals the Argonaute regulatory landscape of the C. elegans germline 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/262113v1?rss=1"
</link>
<description><![CDATA[
piRNAs (Piwi-interacting small RNAs) engage Piwi Argonautes to silence transposons and promote fertility in animal germlines. Genetic and computational studies have suggested that C. elegans piRNAs tolerate mismatched pairing and in principle could target every transcript. Here we employ in vivo cross-linking to identify transcriptome-wide interactions between piRNAs and target RNAs. We show that piRNAs engage all germline mRNAs and that piRNA binding follows microRNA-like pairing rules. Targeting correlates better with binding energy than with piRNA abundance, suggesting that piRNA concentration does not limit targeting. In mRNAs silenced by piRNAs, secondary small RNAs accumulate at the center and ends of piRNA binding sites. In germline-expressed mRNAs, however, targeting by the CSR-1 Argonaute correlates with reduced piRNA binding density and suppression of piRNA-associated secondary small RNAs. Our findings reveal physiologically important and nuanced regulation of individual piRNA targets and provide evidence for a comprehensive post transcriptional regulatory step in germline gene expression.
]]></description>
<dc:creator>Shen, E.-Z.</dc:creator>
<dc:creator>Chen, H.</dc:creator>
<dc:creator>Ozturk, A. R.</dc:creator>
<dc:creator>Tu, S.</dc:creator>
<dc:creator>Shirayama, M.</dc:creator>
<dc:creator>Tang, W.</dc:creator>
<dc:creator>Ding, Y.-H.</dc:creator>
<dc:creator>Dai, S.-Y.</dc:creator>
<dc:creator>Weng, Z.</dc:creator>
<dc:creator>Mello, C. C.</dc:creator>
<dc:date>2018-02-07</dc:date>
<dc:identifier>doi:10.1101/262113</dc:identifier>
<dc:title><![CDATA[Identification of piRNA binding sites reveals the Argonaute regulatory landscape of the C. elegans germline]]></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/cgi/content/short/278747v1?rss=1">
<title>
<![CDATA[
Higher-Order Organization Principles of Pre-translational mRNPs 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/278747v1?rss=1"
</link>
<description><![CDATA[
Compared to noncoding RNAs (ncRNAs) such as rRNAs and ribozymes, for which high resolution structures abound, little is known about the tertiary structures of mRNAs. In eukaryotic cells, newly made mRNAs are packaged with proteins in highly compacted mRNPs, but the manner of this mRNA compaction is unknown. Here we developed and implemented RIPPLiT (RNA ImmunoPrecipitation and Proximity Ligation in Tandem), a transcriptome-wide method for probing the 3D conformations of RNAs stably-associated with defined proteins, in this case exon junction complex (EJC) core factors. EJCs multimerize with other mRNP components to form megadalton sized complexes that protect large swaths of newly synthesized mRNAs from endonuclease digestion. Unlike ncRNAs, mRNAs behave more like flexible polymers without strong locus-specific interactions. Polymer analysis of proximity ligation data for hundreds of mRNA species demonstrates that pre-translational mammalian mRNPs fold as linear rod-like structures with no strong propensity for 5 and 3 end interaction.
]]></description>
<dc:creator>Metkar, M.</dc:creator>
<dc:creator>Ozadam, H.</dc:creator>
<dc:creator>Lajoie, B. R.</dc:creator>
<dc:creator>Imakaev, M.</dc:creator>
<dc:creator>Mirny, L. A.</dc:creator>
<dc:creator>Dekker, J.</dc:creator>
<dc:creator>Moore, M. J.</dc:creator>
<dc:date>2018-03-08</dc:date>
<dc:identifier>doi:10.1101/278747</dc:identifier>
<dc:title><![CDATA[Higher-Order Organization Principles of Pre-translational mRNPs]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/226894v1?rss=1">
<title>
<![CDATA[
Transcriptome-wide analysis of the functional intronome using spliceosome profiling 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/226894v1?rss=1"
</link>
<description><![CDATA[
Full understanding of eukaryotic transcriptomes and how they respond to different conditions requires deep knowledge of all sites of intron excision. Although RNA-Seq provides much of this information, the low abundance of many spliced transcripts (often due to their rapid cytoplasmic decay) limits the ability of RNA-Seq alone to reveal the full repertoire of spliced species. Here we present "spliceosome profiling", a strategy based on deep sequencing of RNAs co-purifying with late stage spliceosomes. Spliceosome profiling allows for unambiguous mapping of intron ends to single nucleotide resolution and branchpoint identification at unprecedented depths. Our data reveal hundreds of new introns in S. pombe and numerous others that were previously misannotated. By providing a means to directly interrogate sites of spliceosome assembly and catalysis genome-wide, spliceosome profiling promises to transform our understanding of RNA processing in the nucleus much like ribosome profiling has transformed our understanding mRNA translation in the cytoplasm.
]]></description>
<dc:creator>Chen, W.</dc:creator>
<dc:creator>Moore, J.</dc:creator>
<dc:creator>Ozadam, H.</dc:creator>
<dc:creator>Shulha, H. P.</dc:creator>
<dc:creator>Rhind, N.</dc:creator>
<dc:creator>Weng, Z.</dc:creator>
<dc:creator>Moore, M. J.</dc:creator>
<dc:date>2017-11-29</dc:date>
<dc:identifier>doi:10.1101/226894</dc:identifier>
<dc:title><![CDATA[Transcriptome-wide analysis of the functional intronome using spliceosome profiling]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2017-11-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/288092v1?rss=1">
<title>
<![CDATA[
Hydrophobicity drives the systemic distribution of lipid-conjugated siRNAs via lipid transport pathways 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/288092v1?rss=1"
</link>
<description><![CDATA[
Efficient delivery of therapeutic RNA is the fundamental obstacle preventing its clinical utility. Lipid conjugation improves plasma half-life, tissue accumulation, and cellular uptake of small interfering RNAs (siRNAs). However, the impact of conjugate structure and hydrophobicity on siRNA pharmacokinetics is unclear, impeding the design of clinically relevant lipid-siRNAs. Using a panel of biologically-occurring lipids, we show that lipid conjugation modulates siRNA hydrophobicity and governs spontaneous partitioning into distinct plasma lipoprotein classes in vivo. Lipoprotein binding influences siRNA distribution by delaying renal excretion and promoting uptake into lipoprotein receptor-enriched tissues. Lipid-siRNAs elicit mRNA silencing without causing toxicity in a tissue-specific manner. Lipid-siRNA internalization occurs independently of lipoprotein endocytosis, and is mediated by siRNA phosphorothioate modifications. Although biomimetic lipoprotein nanoparticles have been considered for the enhancement of siRNA delivery, our findings suggest that hydrophobic modifications can be leveraged to incorporate therapeutic siRNA into endogenous lipid transport pathways without the requirement for synthetic formulation.
]]></description>
<dc:creator>Osborn, M. F.</dc:creator>
<dc:creator>Coles, A. H.</dc:creator>
<dc:creator>Biscans, A.</dc:creator>
<dc:creator>Haraszti, R. A.</dc:creator>
<dc:creator>Roux, L.</dc:creator>
<dc:creator>Davis, S.</dc:creator>
<dc:creator>Ly, S.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Hassler, M. R.</dc:creator>
<dc:creator>Godinho, B. M. D. C.</dc:creator>
<dc:creator>Nikan, M.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:date>2018-03-23</dc:date>
<dc:identifier>doi:10.1101/288092</dc:identifier>
<dc:title><![CDATA[Hydrophobicity drives the systemic distribution of lipid-conjugated siRNAs via lipid transport pathways]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/289439v1?rss=1">
<title>
<![CDATA[
Diverse lipid conjugates for functional extra-hepatic siRNA delivery in vivo 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/289439v1?rss=1"
</link>
<description><![CDATA[
RNAi-based therapeutics show promising clinical data for treatment of liver-associated disorders. However, siRNA delivery into extra-hepatic tissues remains an obstacle, limiting the use of siRNA-based therapies. Here we report on a first example of chemical engineering of lipophilic conjugates to enable extra-hepatic delivery. We synthesized a panel of fifteen lipophilic siRNA and evaluated the impact of their chemical configuration on siRNA tissue distribution profile. Generally, lipophilic conjugates allow siRNA distribution to a wide range of tissues, where the degree of lipophilicity defines the ratio of liver/spleen to kidney distribution. In addition to primary clearance tissues, several conjugates achieve significant siRNA distribution to lung, heart, adrenal glands, fat, muscle. siRNA tissue accumulation leads to productive silencing, shown with two independent targets. siRNA concentrations necessary for productive silencing are tissue and conjugate dependent, varying significantly from 5 to 200 ng/mg. The collection of conjugated siRNA described here enables functional gene modulation in vivo in lung, muscle, fat, heart, adrenal glands opening these tissues for future therapeutic intervention.
]]></description>
<dc:creator>Biscans, A.</dc:creator>
<dc:creator>Coles, A.</dc:creator>
<dc:creator>Haraszti, R.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Hassler, M.</dc:creator>
<dc:creator>Osborn, M.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:date>2018-03-26</dc:date>
<dc:identifier>doi:10.1101/289439</dc:identifier>
<dc:title><![CDATA[Diverse lipid conjugates for functional extra-hepatic siRNA delivery in vivo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-26</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/290999v1?rss=1">
<title>
<![CDATA[
Heavily and Fully Modified RNAs Guide Efficient SpyCas9-Mediated Genome Editing 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/290999v1?rss=1"
</link>
<description><![CDATA[
RNA-based drugs depend on chemical modifications to increase potency and nuclease stability, and to decrease immunogenicity in vivo. Chemical modification will likely improve the guide RNAs involved in CRISPR-Cas9-based therapeutics as well. Cas9 orthologs are RNA-guided microbial effectors that cleave DNA. No studies have yet explored chemical modification at all positions of the crRNA guide and tracrRNA cofactor. Here, we have identified several heavily-modified versions of crRNA and tracrRNA that are more potent than their unmodified counterparts. In addition, we describe fully chemically modified crRNAs and tracrRNAs (containing no 2-OH groups) that are functional in human cells. These designs demonstrate a significant breakthrough for Cas9-based therapeutics since heavily modified RNAs tend to be more stable in vivo (thus increasing potency). We anticipate that our designs will improve the use of Cas9 via RNP and mRNA delivery for in vivo and ex vivo purposes.
]]></description>
<dc:creator>Mir, A.</dc:creator>
<dc:creator>Alterman, J. F.</dc:creator>
<dc:creator>Hassler, M. R.</dc:creator>
<dc:creator>Debacker, A. J.</dc:creator>
<dc:creator>Hudgens, E.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Brodsky, M. H.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Watts, J. K.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:date>2018-03-28</dc:date>
<dc:identifier>doi:10.1101/290999</dc:identifier>
<dc:title><![CDATA[Heavily and Fully Modified RNAs Guide Efficient SpyCas9-Mediated Genome Editing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-03-28</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/261917v1?rss=1">
<title>
<![CDATA[
An Automated Bayesian Pipeline for Rapid Analysis of Single-Molecule Binding Data 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/261917v1?rss=1"
</link>
<description><![CDATA[
Single-molecule binding assays enable the study of how molecular machines assemble and function. Current algorithms can identify and locate individual molecules, but require tedious manual validation of each spot. Moreover, no solution for high-throughput analysis of single-molecule binding data exists. Here, we describe an automated pipeline to analyze single-molecule data over a wide range of experimental conditions. We benchmarked the pipeline by measuring the binding properties of the well-studied, DNA-guided DNA endonuclease, TtAgo, an Argonaute protein from the Eubacterium Thermus thermophilus. We also used the pipeline to extend our understanding of TtAgo by measuring the proteins binding kinetics at physiological temperatures and for target DNAs containing multiple, adjacent binding sites.
]]></description>
<dc:creator>Smith, C. S.</dc:creator>
<dc:creator>Jouravleva, K.</dc:creator>
<dc:creator>Huisman, M.</dc:creator>
<dc:creator>Jolly, S. M.</dc:creator>
<dc:creator>Zamore, P. D.</dc:creator>
<dc:creator>Grunwald, D.</dc:creator>
<dc:date>2018-04-11</dc:date>
<dc:identifier>doi:10.1101/261917</dc:identifier>
<dc:title><![CDATA[An Automated Bayesian Pipeline for Rapid Analysis of Single-Molecule Binding Data]]></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/cgi/content/short/261545v1?rss=1">
<title>
<![CDATA[
PIWI Proteins Act at Multiple Steps in the Production of Their Own Guides 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/261545v1?rss=1"
</link>
<description><![CDATA[
In animals, piRNAs guide PIWI-proteins to silence transposons and regulate gene expression. The mechanisms for making piRNAs have been proposed to differ among cell types, tissues, and animals. Our data instead suggest a single model that explains piRNA production in most animals. piRNAs initiate piRNA production by guiding PIWI proteins to slice precursor transcripts. Next, PIWI proteins direct the stepwise fragmentation of the sliced precursor transcripts, yielding tail-to-head strings of phased pre-piRNAs. Our analyses detect evidence for this piRNA biogenesis strategy across an evolutionarily broad range of animals including humans. Thus, PIWI proteins initiate and sustain piRNA biogenesis by the same mechanism in species whose last common ancestor predates the branching of most animal lineages. The unified model places PIWI-clade Argonautes at the center of piRNA biology and suggests that the ancestral animal--the Urmetazoan--used PIWI proteins both to generate piRNA guides and to execute piRNA function.
]]></description>
<dc:creator>Zamore, P.</dc:creator>
<dc:creator>Gainetdinov, I.</dc:creator>
<dc:creator>Coplan, C.</dc:creator>
<dc:creator>Cecchini, K.</dc:creator>
<dc:date>2018-02-07</dc:date>
<dc:identifier>doi:10.1101/261545</dc:identifier>
<dc:title><![CDATA[PIWI Proteins Act at Multiple Steps in the Production of Their Own Guides]]></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/cgi/content/short/172650v1?rss=1">
<title>
<![CDATA[
NmeCas9 is an intrinsically high-fidelity genome editing platform 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/172650v1?rss=1"
</link>
<description><![CDATA[
BackgroundThe development of CRISPR genome editing has transformed biomedical research. Most applications reported thus far rely upon the Cas9 protein from Streptococcus pyogenes SF370 (SpyCas9). With many RNA guides, wild-type SpyCas9 can induce significant levels of unintended mutations at near-cognate sites, necessitating substantial efforts toward the development of strategies to minimize off-target activity. Although the genome-editing potential of thousands of other Cas9 orthologs remains largely untapped, it is not known how many will require similarly extensive engineering to achieve single-site accuracy within large (e.g. mammalian) genomes. In addition to its off-targeting propensity, SpyCas9 is encoded by a relatively large (~4.2 kb) open reading frame, limiting its utility in applications that require size-restricted delivery strategies such as adeno-associated virus vectors. In contrast, some genome-editing-validated Cas9 orthologs (e.g. from Staphylococcus aureus, Campylobacter jejuni, Geobacillus stearothermophilus and Neisseria meningitidis) are considerably smaller and therefore better suited for viral delivery.nnResultsHere we show that wild-type NmeCas9, when programmed with guide sequences of natural length (24 nucleotides), exhibits a nearly complete absence of unintended editing in human cells, even when targeting sites that are prone to off-target activity with wildtype SpyCas9. We also validate at least six variant protospacer adjacent motifs (PAMs), in addition to the preferred consensus PAM (5-N4GATT-3), for NmeCas9 genome editing in human cells.nnConclusionsOur results show that NmeCas9 is a naturally high-fidelity genome editing enzyme and suggest that additional Cas9 orthologs may prove to exhibit similarly high accuracy, even without extensive engineering.
]]></description>
<dc:creator>Amrani, N.</dc:creator>
<dc:creator>Gao, X. D.</dc:creator>
<dc:creator>Liu, P.</dc:creator>
<dc:creator>Gupta, A.</dc:creator>
<dc:creator>Edraki, A.</dc:creator>
<dc:creator>Ibraheim, R.</dc:creator>
<dc:creator>Sasaki, K. E.</dc:creator>
<dc:creator>Zhu, L. J.</dc:creator>
<dc:creator>Wolfe, S. A.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:date>2017-08-04</dc:date>
<dc:identifier>doi:10.1101/172650</dc:identifier>
<dc:title><![CDATA[NmeCas9 is an intrinsically high-fidelity genome editing platform]]></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/cgi/content/short/295055v1?rss=1">
<title>
<![CDATA[
All-in-One Adeno-associated Virus Delivery and Genome Editing by Neisseria meningitidis Cas9 in vivo 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/295055v1?rss=1"
</link>
<description><![CDATA[
Clustered, regularly interspaced, short palindromic repeats (CRISPR) and CRISPR-associated proteins (Cas) have recently opened a new avenue for gene therapy. Cas9 nuclease guided by a single-guide RNA (sgRNA) has been extensively used for genome editing. Currently, three Cas9 orthologs have been adapted for in vivo genome engineering applications: SpyCas9, SauCas9 and CjeCas9. However, additional in vivo editing platforms are needed, in part to enable a greater range of sequences to be accessed via viral vectors, especially those in which Cas9 and sgRNA are combined into a single vector genome. Here, we present an additional in vivo editing platform using Neisseria meningitidis Cas9 (NmeCas9). NmeCas9 is compact, edits with high accuracy, and possesses a distinct PAM, making it an excellent candidate for safe gene therapy applications. We find that NmeCas9 can be used to target the Pcsk9 and Hpd genes in mice. Using tail vein hydrodynamic-based delivery of NmeCas9 plasmid to target the Hpd gene, we successfully reprogrammed the tyrosine degradation pathway in Hereditary Tyrosinemia Type I mice. More importantly, we delivered NmeCas9 with its single-guide RNA in a single recombinant adeno-associated vector (rAAV) to target Pcsk9, resulting in lower cholesterol levels in mice. This all-in-one vector yielded >35% gene modification after two weeks of vector administration, with minimal off-target cleavage in vivo. Our findings indicate that NmeCas9 can facilitate future efforts to correct disease-causing mutations by expanding the targeting scope of RNA-guided nucleases.
]]></description>
<dc:creator>Ibraheim, R.</dc:creator>
<dc:creator>Song, C.-Q.</dc:creator>
<dc:creator>Mir, A.</dc:creator>
<dc:creator>Amrani, N.</dc:creator>
<dc:creator>Xue, W.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:date>2018-04-04</dc:date>
<dc:identifier>doi:10.1101/295055</dc:identifier>
<dc:title><![CDATA[All-in-One Adeno-associated Virus Delivery and Genome Editing by Neisseria meningitidis Cas9 in vivo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-04-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/344572v1?rss=1">
<title>
<![CDATA[
Maelstrom Represses Canonical Polymerase II Transcription within Bi-Directional piRNA Clusters in Drosophila melanogaster 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/344572v1?rss=1"
</link>
<description><![CDATA[
In Drosophila, 23-30 nt long PIWI-interacting RNAs (piRNAs) direct the protein Piwi to silence germline transposon transcription. Most germline piRNAs derive from dual-strand piRNA clusters, heterochromatic transposon graveyards that are transcribed from both genomic strands. These piRNA sources are marked by the Heterochromatin Protein 1 homolog, Rhino (Rhi), which facilitates their promoter-independent transcription, suppresses splicing, and inhibits transcriptional termination. Here, we report that the protein Maelstrom (Mael) represses canonical, promoter-dependent transcription in dual-strand clusters, allowing Rhi to initiate piRNA precursor transcription. In addition to Mael, the piRNA biogenesis factors Armitage and Piwi, but not Rhi, are required to repress canonical transcription in dual-strand clusters. We propose that Armitage, Piwi, and Mael collaborate to repress potentially dangerous transcription of individual transposon mRNAs within clusters, while Rhi allows non-canonical transcription of the clusters into piRNA precursors without generating transposase-encoding mRNAs.
]]></description>
<dc:creator>Chang, T. H.</dc:creator>
<dc:creator>Mattei, E.</dc:creator>
<dc:creator>Gainetdinov, I.</dc:creator>
<dc:creator>Weng, Z.</dc:creator>
<dc:creator>Zamore, P.</dc:creator>
<dc:date>2018-06-12</dc:date>
<dc:identifier>doi:10.1101/344572</dc:identifier>
<dc:title><![CDATA[Maelstrom Represses Canonical Polymerase II Transcription within Bi-Directional piRNA Clusters in Drosophila melanogaster]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-06-12</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/350504v1?rss=1">
<title>
<![CDATA[
Potent Cas9 inhibition in bacterial and human cells by new anti-CRISPR protein families 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/350504v1?rss=1"
</link>
<description><![CDATA[
CRISPR-Cas systems are widely used for genome engineering technologies, and in their natural setting, they play crucial roles in bacterial and archaeal adaptive immunity, protecting against phages and other mobile genetic elements. Previously we discovered bacteriophage-encoded Cas9-specific anti-CRISPR (Acr) proteins that serve as countermeasures against host bacterial immunity by inactivating their CRISPR-Cas systems1. We hypothesized that the evolutionary advantages conferred by anti-CRISPRs would drive the widespread occurrence of these proteins in nature2-4. We have identified new anti-CRISPRs using the bioinformatic approach that successfully identified previous Acr proteins1 against Neisseria meningitidis Cas9 (NmeCas9). In this work we report two novel anti-CRISPR families in strains of Haemophilus parainfluenzae and Simonsiella muelleri, both of which harbor type II-C CRISPR-Cas systems5. We characterize the type II-C Cas9 orthologs from H. parainfluenzae and S. muelleri, show that the newly identified Acrs are able to inhibit these systems, and define important features of their inhibitory mechanisms. The S. muelleri Acr is the most potent NmeCas9 inhibitor identified to date. Although inhibition of NmeCas9 by anti-CRISPRs from H. parainfluenzae and S. muelleri reveals cross-species inhibitory activity, more distantly related type II-C Cas9s are not inhibited by these proteins. The specificities of anti-CRISPRs and divergent Cas9s appear to reflect co-evolution of their strategies to combat or evade each other. Finally, we validate these new anti-CRISPR proteins as potent off-switches for Cas9 genome engineering applications.
]]></description>
<dc:creator>Lee, J.</dc:creator>
<dc:creator>Mir, A.</dc:creator>
<dc:creator>Edraki, A.</dc:creator>
<dc:creator>Garcia, B.</dc:creator>
<dc:creator>Amrani, N.</dc:creator>
<dc:creator>Lou, H. E.</dc:creator>
<dc:creator>Gainetdinov, I.</dc:creator>
<dc:creator>Pawluk, A.</dc:creator>
<dc:creator>Ibraheim, R.</dc:creator>
<dc:creator>Gao, X. D.</dc:creator>
<dc:creator>Liu, P.</dc:creator>
<dc:creator>Davidson, A. R.</dc:creator>
<dc:creator>Maxwell, K. L.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:date>2018-06-20</dc:date>
<dc:identifier>doi:10.1101/350504</dc:identifier>
<dc:title><![CDATA[Potent Cas9 inhibition in bacterial and human cells by new anti-CRISPR protein families]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-06-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/352260v1?rss=1">
<title>
<![CDATA[
Robust genome editing with short single-stranded and long, partially single-stranded DNA donors in C. elegans 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/352260v1?rss=1"
</link>
<description><![CDATA[
CRISPR-based genome editing using ribonucleoprotein (RNP) complexes and synthetic single stranded oligodeoxynucleotide (ssODN) donors can be highly effective. However, reproducibility can vary, and precise, targeted integration of longer constructs - such as green fluorescent protein (GFP) tags remains challenging in many systems. Here we describe a streamlined and optimized editing protocol for the nematode C. elegans. We demonstrate its efficacy, flexibility, and cost-effectiveness by affinity-tagging all twelve of the Worm-specific Argonaute (WAGO) proteins in C. elegans using ssODN donors. In addition, we describe a novel PCR-based partially single-stranded "hybrid" donor design that yields high efficiency editing with large (kilobase-scale) constructs. We use these hybrid donors to introduce fluorescent protein tags into multiple loci achieving editing efficiencies that approach those previously obtained only with much shorter ssODN donors. The principals and strategies described here are likely to translate to other systems and should allow researchers to reproducibly and efficiently obtain both long and short precision genome edits.
]]></description>
<dc:creator>Mello, C.</dc:creator>
<dc:creator>Dokshin, G. A.</dc:creator>
<dc:creator>Ghanta, K. S.</dc:creator>
<dc:creator>Piscopo, K. M.</dc:creator>
<dc:date>2018-06-20</dc:date>
<dc:identifier>doi:10.1101/352260</dc:identifier>
<dc:title><![CDATA[Robust genome editing with short single-stranded and long, partially single-stranded DNA donors in C. elegans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-06-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/365890v1?rss=1">
<title>
<![CDATA[
The Genetic Landscape of Diamond-Blackfan Anemia 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/365890v1?rss=1"
</link>
<description><![CDATA[
Diamond-Blackfan anemia (DBA) is a rare bone marrow failure disorder that affects 1 in 100,000 to 200,000 live births and has been associated with mutations in components of the ribosome. In order to characterize the genetic landscape of this genetically heterogeneous disorder, we recruited a cohort of 472 individuals with a clinical diagnosis of DBA and performed whole exome sequencing (WES). Overall, we identified rare and predicted damaging mutations in likely causal genes for 78% of individuals. The majority of mutations were singletons, absent from population databases, predicted to cause loss of function, and in one of 19 previously reported genes encoding for a diverse set of ribosomal proteins (RPs). Using WES exon coverage estimates, we were able to identify and validate 31 deletions in DBA associated genes. We also observed an enrichment for extended splice site mutations and validated the diverse effects of these mutations using RNA sequencing in patientderived cell lines. Leveraging the size of our cohort, we observed several robust genotype-phenotype associations with congenital abnormalities and treatment outcomes. In addition to comprehensively identifying mutations in known genes, we further identified rare mutations in 7 previously unreported RP genes that may cause DBA. We also identified several distinct disorders that appear to phenocopy DBA, including 9 individuals with biallelic CECR1 mutations that result in deficiency of ADA2. However, no new genes were identified at exome-wide significance, suggesting that there are no unidentified genes containing mutations readily identified by WES that explain > 5% of DBA cases. Overall, this comprehensive report should not only inform clinical practice for DBA patients, but also the design and analysis of future rare variant studies for heterogeneous Mendelian disorders.
]]></description>
<dc:creator>Ulirsch, J. C.</dc:creator>
<dc:creator>Verboon, J. M.</dc:creator>
<dc:creator>Kazerounian, S.</dc:creator>
<dc:creator>Guo, M. H.</dc:creator>
<dc:creator>Yuan, D.</dc:creator>
<dc:creator>Ludwig, L. S.</dc:creator>
<dc:creator>Handsaker, R. E.</dc:creator>
<dc:creator>Abdulhay, N. J.</dc:creator>
<dc:creator>Fiorini, C.</dc:creator>
<dc:creator>Genovese, G.</dc:creator>
<dc:creator>Lim, E. T.</dc:creator>
<dc:creator>Cheng, A.</dc:creator>
<dc:creator>Cummings, B. B.</dc:creator>
<dc:creator>Chao, K. R.</dc:creator>
<dc:creator>Beggs, A. H.</dc:creator>
<dc:creator>Genetti, C. A.</dc:creator>
<dc:creator>Sieff, C. A.</dc:creator>
<dc:creator>Newburger, P. E.</dc:creator>
<dc:creator>Niewiadomska, E.</dc:creator>
<dc:creator>Matysiak, M.</dc:creator>
<dc:creator>Vlachos, A.</dc:creator>
<dc:creator>Lipton, J. M.</dc:creator>
<dc:creator>Atsidaftos, E.</dc:creator>
<dc:creator>Glader, B.</dc:creator>
<dc:creator>Narla, A.</dc:creator>
<dc:creator>Gleizes, P.-E.</dc:creator>
<dc:creator>O'Donohue, M.-F.</dc:creator>
<dc:creator>Montel-Lehry, N.</dc:creator>
<dc:creator>Amor, D. J.</dc:creator>
<dc:creator>McCarroll, S. A.</dc:creator>
<dc:creator>O'Donnell-Luria, A. H.</dc:creator>
<dc:creator>Gupta, N.</dc:creator>
<dc:creator>Gabriel, S. B.</dc:creator>
<dc:creator>MacArthur, D. G.</dc:creator>
<dc:creator>Lander, E. S.</dc:creator>
<dc:creator>Lek, M.</dc:creator>
<dc:creator>Da Costa, L.</dc:creator>
<dc:creator>Nathan, D. G.</dc:creator>
<dc:creator>Korostelev, A. K.</dc:creator>
<dc:creator>Do, R.</dc:creator>
<dc:creator>Sank</dc:creator>
<dc:date>2018-07-10</dc:date>
<dc:identifier>doi:10.1101/365890</dc:identifier>
<dc:title><![CDATA[The Genetic Landscape of Diamond-Blackfan Anemia]]></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/cgi/content/short/396424v1?rss=1">
<title>
<![CDATA[
Photon count estimation in single-molecule localization microscopy 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/396424v1?rss=1"
</link>
<description><![CDATA[
Recently, Franke, Sauer and van de Linde1 introduced a way to estimate the axial position of single-molecules (TRABI). To this end, they compared the detected photon count from a temporal radial-aperture-based intensity estimation to the estimated count from Gaussian point-spread function (PSF) fitting to the data. Empirically they found this photometric ratio to be around 0.7-0.8 close to focus and decreasing away from it. Here, we explain this reported but unexplained discrepancy and furthermore show that the photometric ratio as indicator for axial position is susceptible even to typical optical aberrations.
]]></description>
<dc:creator>Rieger, B.</dc:creator>
<dc:creator>Stallinga, S.</dc:creator>
<dc:creator>Hulleman, C. N.</dc:creator>
<dc:creator>Thorsen, R. O.</dc:creator>
<dc:creator>Grunwald, D.</dc:creator>
<dc:creator>Hammer, M.</dc:creator>
<dc:date>2018-08-20</dc:date>
<dc:identifier>doi:10.1101/396424</dc:identifier>
<dc:title><![CDATA[Photon count estimation in single-molecule localization microscopy]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/399931v1?rss=1">
<title>
<![CDATA[
DEBrowser: Interactive Differential Expression Analysis and Visualization Tool for Count Data 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/399931v1?rss=1"
</link>
<description><![CDATA[
BackgroundSequencing data has become a standard measure for studying diverse cellular activities. For example, gene expression is accurately measured by RNA sequencing (RNA-Seq) libraries, protein-DNA interactions are captured by chromatin immunoprecipitation sequencing (ChIP-Seq), protein-RNA interactions by crosslinking immunoprecipitation (CLIP-Seq) or RNA immunoprecipitation (RIP-Seq) sequencing, DNA accessibility by assay for transposase-accessible chromatin (ATAC-Seq), and DNase or MNase sequencing libraries. Analysis of these sequencing techniques involve library-specific approaches. However, in all cases, once the sequencing libraries are processed, the result is a count table specifying the estimated number of reads originating from a genomic locus. Differential analysis to determine which loci have different cellular activity under different conditions starts with the count table and iterates through a cycle of data assessment, preparation and analysis. Such iterative approach relies on multiple programs and is therefore a challenge for those without programming skills.nnResultsWe developed DEBrowser, as an R bioconductor project, to interactively visualize each step of the differential analysis of count data, without any requirement for programming expertise. The application presents a rich and interactive web based graphical user interface based on Rs shiny infrastructure. We use shinys reactive programming interface for a dynamic webpage that responds to user input and integrates its visualization widgets at each stage of the analysis. In this way, every step of the analysis can be displayed in one application that combines many approaches and multiple results. We show DEBrowsers capabilities by reproducing the analysis of two previously published data sets.nnConclusionsDEBrowser is a flexible, intuitive, web-based analysis platform that enables an iterative and interactive analysis of count data without any requirement of programming knowledge.
]]></description>
<dc:creator>Kucukural, A.</dc:creator>
<dc:creator>Yukselen, O.</dc:creator>
<dc:creator>Ozata, D. M.</dc:creator>
<dc:creator>Moore, M. J.</dc:creator>
<dc:creator>Garber, M.</dc:creator>
<dc:date>2018-08-24</dc:date>
<dc:identifier>doi:10.1101/399931</dc:identifier>
<dc:title><![CDATA[DEBrowser: Interactive Differential Expression Analysis and Visualization Tool for Count Data]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-24</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/445825v1?rss=1">
<title>
<![CDATA[
The RNA-binding ATPase, Armitage, Couples piRNA Amplification in Nuage to Phased piRNA Production on Mitochondria 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/445825v1?rss=1"
</link>
<description><![CDATA[
PlWI-interacting RNAs (piRNAs) silence transposons in Drosophila ovaries, ensuring female fertility. Two coupled pathways generate germline piRNAs: the ping-pong cycle, in which the PIWI proteins Aubergine and Ago3 increase the abundance of pre-existing piRNAs, and the phased piRNA pathway, which generates strings of tail-to-head piRNAs, one after another. Proteins acting in the ping-pong cycle localize to nuage, whereas phased piRNA production requires Zucchini, an endonuclease on the mitochondrial surface. Here, we report that Armitage (Armi), an RNA-binding ATPase localized to both nuage and mitochondria, links the ping-pong cycle to the phased piRNA pathway. Mutations that block phased piRNA production deplete Armi from nuage. Armi ATPase mutants cannot support phased piRNA production and inappropriately bind mRNA instead of piRNA precursors. We propose that Armi shuttles between nuage and mitochondria, feeding precursor piRNAs generated by Ago3 cleavage into the Zucchini-dependent production of Aubergine- and Piwi-bound piRNAs on the mitochondrial surface.
]]></description>
<dc:creator>Ge, D. T.</dc:creator>
<dc:creator>Wang, W.</dc:creator>
<dc:creator>Tipping, C.</dc:creator>
<dc:creator>Gainetdinov, I.</dc:creator>
<dc:creator>Weng, Z.</dc:creator>
<dc:creator>Zamore, P. D.</dc:creator>
<dc:date>2018-10-17</dc:date>
<dc:identifier>doi:10.1101/445825</dc:identifier>
<dc:title><![CDATA[The RNA-binding ATPase, Armitage, Couples piRNA Amplification in Nuage to Phased piRNA Production on Mitochondria]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-10-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/570200v1?rss=1">
<title>
<![CDATA[
GCNA interacts with Spartan and Topoisomerase II to regulate genome stability. 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/570200v1?rss=1"
</link>
<description><![CDATA[
GCNA proteins are expressed across eukarya in pluripotent cells and have conserved functions in fertility. GCNA homologs Spartan/DVC-1 and Wss1 resolve DNA-protein crosslinks (DPCs), including Topoisomerase-DNA adducts, during DNA replication. We show that GCNA and Topoisomerase 2 (Top2) physically interact and colocalize on condensed chromosomes during mitosis, when Spartan is not present. We show that C. elegans gcna-1 mutants are sensitive to Top2 poison and accumulate mutations consistent with low fidelity repair of DNA damage, leading to loss of fitness and fertility over generations. We also demonstrate that mouse GCNA interacts with TOP2, and Gcna-mutant mice exhibit abnormalities consistent with the inability to process DPCs, including chromatin condensation and crossover defects. Together, our findings provide evidence that GCNA maintains genomic integrity by processing Top2 DPCs in the germline and early embryo, where the genome is challenged with an increased DPC burden.
]]></description>
<dc:creator>Davis, G. M.</dc:creator>
<dc:creator>Dokshin, G.</dc:creator>
<dc:creator>Sawle, A. D.</dc:creator>
<dc:creator>Eldridge, M. D.</dc:creator>
<dc:creator>Romer, K. A.</dc:creator>
<dc:creator>Gourley, T. E.</dc:creator>
<dc:creator>Molesworth, L. W.</dc:creator>
<dc:creator>Tatnell, H. R.</dc:creator>
<dc:creator>Ozturk, A. R.</dc:creator>
<dc:creator>de Rooij, D. G.</dc:creator>
<dc:creator>Hannon, G. J.</dc:creator>
<dc:creator>Page, D. C.</dc:creator>
<dc:creator>Mello, C. C.</dc:creator>
<dc:creator>Carmell, M. A.</dc:creator>
<dc:date>2019-03-07</dc:date>
<dc:identifier>doi:10.1101/570200</dc:identifier>
<dc:title><![CDATA[GCNA interacts with Spartan and Topoisomerase II to regulate genome stability.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/580167v1?rss=1">
<title>
<![CDATA[
High-resolution cryo-EM structures of outbreak strain human norovirus shells reveal size variations 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/580167v1?rss=1"
</link>
<description><![CDATA[
Noroviruses are a leading cause of food-borne illnesses worldwide. Although GII.4 strains have been responsible for most norovirus outbreaks, the assembled virus shell structures have been available in detail for only a single strain (GI.1). We present high-resolution (2.6-4.1 [A]) cryo-electron microscopy (cryo-EM) structures of GII.4, GII.2, GI.7 and GI.1 human norovirus outbreak strain virus-like particles (VLPs). Although norovirus VLPs have been thought to exist in a single-sized assembly, our structures reveal polymorphism between and within genogroups with small, medium and large particle sizes observed. We developed a new asymmetric reconstruction method and resolved a metal ion adjacent to the co-receptor binding site, which affected the structural stability of the shell. Our structures serve as valuable templates for facilitating vaccine formulations.
]]></description>
<dc:creator>Jung, J.</dc:creator>
<dc:creator>Grant, T.</dc:creator>
<dc:creator>Thomas, D. R.</dc:creator>
<dc:creator>Diehnelt, C. W.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:creator>Joshua-Tor, L.</dc:creator>
<dc:date>2019-03-16</dc:date>
<dc:identifier>doi:10.1101/580167</dc:identifier>
<dc:title><![CDATA[High-resolution cryo-EM structures of outbreak strain human norovirus shells reveal size variations]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-03-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/600445v1?rss=1">
<title>
<![CDATA[
Extensive ribosome and RF2 rearrangements during translation termination 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/600445v1?rss=1"
</link>
<description><![CDATA[
Protein synthesis ends when a ribosome reaches an mRNA stop codon. Release factors (RFs) decode the stop codon, hydrolyze peptidyl-tRNA to release the nascent protein, and then dissociate to allow ribosome recycling. To visualize termination by RF2, we resolved a cryo-EM ensemble of E. coli 70S*RF2 structures at up to 3.3 [A] in a single sample. Five structures suggest a highly dynamic termination pathway. Upon peptidyl-tRNA hydrolysis, the CCA end of deacyl-tRNA departs from the peptidyl transferase center. The catalytic GGQ loop of RF2 is rearranged into a long {beta}-hairpin that plugs the peptide tunnel, biasing a nascent protein toward the ribosome exit. Ribosomal intersubunit rotation destabilizes the catalytic RF2 domain on the 50S subunit and disassembles the central intersubunit bridge B2a, resulting in RF2 departure. Our structures visualize how local rearrangements and spontaneous inter-subunit rotation poise the newly-made protein and RF2 to dissociate in preparation for ribosome recycling.
]]></description>
<dc:creator>Svidritskiy, E.</dc:creator>
<dc:creator>Demo, G.</dc:creator>
<dc:creator>Loveland, A. B.</dc:creator>
<dc:creator>Xu, C.</dc:creator>
<dc:creator>Korostelev, A. A.</dc:creator>
<dc:date>2019-04-05</dc:date>
<dc:identifier>doi:10.1101/600445</dc:identifier>
<dc:title><![CDATA[Extensive ribosome and RF2 rearrangements during translation termination]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-04-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/623447v1?rss=1">
<title>
<![CDATA[
Free circular introns with an unusual branchpoint in neuronal projections 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/623447v1?rss=1"
</link>
<description><![CDATA[
The polarized structure of axons and dendrites in neuronal cells depends in part on RNA localization. Previous studies have looked at which polyadenylated RNAs are enriched in neuronal projections or at synapses, but less is known about the distribution of non-adenylated RNAs. By physically dissecting projections from cell bodies of primary rat hippocampal neurons and sequencing total RNA, we found an unexpected set of free circular introns with a non-canonical branchpoint enriched in neuronal projections. These introns appear to be tailless lariats that escape debranching. They lack ribosome occupancy, sequence conservation, and known localization signals, and their function, if any, is not known. Nonetheless, their enrichment in projections has important implications for our understanding of the mechanisms by which RNAs reach distal compartments of asymmetric cells.
]]></description>
<dc:creator>Eddy, S. R.</dc:creator>
<dc:creator>Saini, H.</dc:creator>
<dc:creator>Moore, M. J.</dc:creator>
<dc:creator>Bicknell, A. A.</dc:creator>
<dc:date>2019-04-30</dc:date>
<dc:identifier>doi:10.1101/623447</dc:identifier>
<dc:title><![CDATA[Free circular introns with an unusual branchpoint in neuronal projections]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-04-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/792960v1?rss=1">
<title>
<![CDATA[
Structure of the Vesicular Stomatitis Virus L Protein in Complex with Its Phosphoprotein Cofactor 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/792960v1?rss=1"
</link>
<description><![CDATA[
The large (L) proteins of non-segmented, negative-strand RNA viruses are multifunctional enzymes that produce capped, methylated and polyadenylated mRNAs and replicate the viral genome. A phosphoprotein (P), required for efficient RNA-dependent RNA polymerization from the viral ribonucleoprotein (RNP) template, regulates function and conformation of the L protein. We report the structure of vesicular stomatitis virus L in complex with its P cofactor determined by electron cryomicroscopy at 3.0 [A] resolution, enabling us to visualize bound segments of P. The contacts of three P segments with multiple L domains show how P induces a closed, compact, initiation-competent conformation. Binding of P to L positions its N-terminal domain adjacent to a putative RNA exit channel for efficient encapsidation of newly synthesized genomes with the nucleoprotein and orients its C-terminal domain to interact with the RNP template. The model shows that a conserved tryptophan in the priming loop can support the initiating 5-nucleotide.
]]></description>
<dc:creator>Jenni, S.</dc:creator>
<dc:creator>Bloyet, L.-M.</dc:creator>
<dc:creator>Diaz-Avalos, R.</dc:creator>
<dc:creator>Liang, B.</dc:creator>
<dc:creator>Whelan, S. P. J.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:creator>Harrison, S. C.</dc:creator>
<dc:date>2019-10-03</dc:date>
<dc:identifier>doi:10.1101/792960</dc:identifier>
<dc:title><![CDATA[Structure of the Vesicular Stomatitis Virus L Protein in Complex with Its Phosphoprotein Cofactor]]></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/cgi/content/short/386201v1?rss=1">
<title>
<![CDATA[
An Evolutionarily Conserved piRNA-producing Locus Required for Male Mouse Fertility 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/386201v1?rss=1"
</link>
<description><![CDATA[
Pachytene piRNAs, which comprise >80% of small RNAs in the adult mouse testis, have been proposed to bind and regulate target RNAs like miRNAs, cleave targets like siRNAs, or lack biological function altogether. Although piRNA pathway protein mutants are male sterile, no biological function has been identified for any mammalian piRNA-producing locus. Here, we report that males lacking piRNAs from a conserved mouse pachytene piRNA locus on chromosome 6 (pi6) produce sperm with defects in capacitation and egg fertilization. Moreover, heterozygous embryos sired by pi6-/- fathers show reduced viability in utero. Molecular analyses suggest that pi6 piRNAs repress gene expression by cleaving mRNAs encoding proteins required for sperm function. pi6 also participates in a network of piRNA-piRNA precursor interactions that initiate piRNA production from a second piRNA locus on chromosome 10 as well as pi6 itself. Our data establish a direct role for pachytene piRNAs in spermiogenesis and embryo viability.nnHighlightsO_LINormal male mouse fertility and spermiogenesis require piRNAs from the pi6 locusnC_LIO_LISperm capacitation and binding to the zona pellucida of the egg require pi6 piRNAsnC_LIO_LIHeterozygous embryos sired by pi6-/- fathers show reduced viability in uteronC_LIO_LIDefects in pi6 mutant sperm reflect changes in the abundance of specific mRNAs.nC_LI
]]></description>
<dc:creator>Wu, P.-H.</dc:creator>
<dc:creator>Fu, Y.</dc:creator>
<dc:creator>Cecchini, K.</dc:creator>
<dc:creator>Ozata, D. M.</dc:creator>
<dc:creator>Weng, Z.</dc:creator>
<dc:creator>Zamore, P. D.</dc:creator>
<dc:date>2018-08-07</dc:date>
<dc:identifier>doi:10.1101/386201</dc:identifier>
<dc:title><![CDATA[An Evolutionarily Conserved piRNA-producing Locus Required for Male Mouse Fertility]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-08-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/864199v1?rss=1">
<title>
<![CDATA[
Efficient Homology-directed Repair with Circular ssDNA Donors 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/864199v1?rss=1"
</link>
<description><![CDATA[
While genome editing has been revolutionized by the advent of CRISPR-based nucleases, difficulties in achieving efficient, nuclease-mediated, homology-directed repair (HDR) still limit many applications. Commonly used DNA donors such as plasmids suffer from low HDR efficiencies in many cell types, as well as integration at unintended sites. In contrast, single-stranded DNA (ssDNA) donors can produce efficient HDR with minimal off-target integration. Here, we describe the use of ssDNA phage to efficiently and inexpensively produce long circular ssDNA (cssDNA) donors. These cssDNA donors serve as efficient HDR templates when used with Cas9 or Cas12a, with integration frequencies superior to linear ssDNA (lssDNA) donors. To evaluate the relative efficiencies of imprecise and precise repair for a suite of different Cas9 or Cas12a nucleases, we have developed a modified Traffic Light Reporter (TLR) system [TLR-Multi-Cas Variant 1 (MCV1)] that permits side-by-side comparisons of different nuclease systems. We used this system to assess editing and HDR efficiencies of different nuclease platforms with distinct DNA donor types. We then extended the analysis of DNA donor types to evaluate efficiencies of fluorescent tag knock-ins at endogenous sites in HEK293T and K562 cells. Our results show that cssDNA templates produce efficient and robust insertion of reporter tags. Targeting efficiency is high, allowing production of biallelic integrants using cssDNA donors. cssDNA donors also outcompete lssDNA donors in template-driven repair at the target site. These data demonstrate that circular donors provide an efficient, cost-effective method to achieve knock-ins in mammalian cell lines.
]]></description>
<dc:creator>Iyer, S.</dc:creator>
<dc:creator>Mir, A.</dc:creator>
<dc:creator>Ibraheim, R.</dc:creator>
<dc:creator>Lee, J.</dc:creator>
<dc:creator>VegaBadillo, J.</dc:creator>
<dc:creator>Roscoe, B.</dc:creator>
<dc:creator>Zhu, L. J.</dc:creator>
<dc:creator>Liu, P.</dc:creator>
<dc:creator>Luk, K.</dc:creator>
<dc:creator>Mintzer, E.</dc:creator>
<dc:creator>de Brito, J. S.</dc:creator>
<dc:creator>Zamore, P.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:creator>Wolfe, S.</dc:creator>
<dc:date>2019-12-05</dc:date>
<dc:identifier>doi:10.1101/864199</dc:identifier>
<dc:title><![CDATA[Efficient Homology-directed Repair with Circular ssDNA Donors]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-12-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2020.02.05.936120v1?rss=1">
<title>
<![CDATA[
mRNA stem-loops can pause the ribosome by hindering A-site tRNA binding 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.02.05.936120v1?rss=1"
</link>
<description><![CDATA[
Although the elongating ribosome is an efficient helicase, certain mRNA stem-loop structures are known to impede ribosome movement along mRNA and stimulate programmed ribosome frameshifting via mechanisms that are not well understood. Using biochemical and single-molecule Forster resonance energy transfer (smFRET) experiments, we studied how frameshift-inducing stem-loops from E. coli dnaX mRNA and the gag-pol transcript of Human Immunodeficiency Virus (HIV) perturb translation elongation. We find that upon encountering the ribosome, the stem-loops strongly inhibit A-site tRNA binding and ribosome intersubunit rotation that accompanies translation elongation. Electron cryo-microscopy (cryo-EM) reveals that the HIV stem-loop docks into the A site of the ribosome. Our results suggest that mRNA stem-loops can transiently escape ribosome helicase by binding to the A site. Thus, the stem-loops can modulate gene expression by sterically hindering tRNA binding and inhibiting translation elongation.
]]></description>
<dc:creator>Bao, C.</dc:creator>
<dc:creator>Loerch, S.</dc:creator>
<dc:creator>Ling, C.</dc:creator>
<dc:creator>Korostelev, A. A.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:creator>Ermolenko, D.</dc:creator>
<dc:date>2020-02-06</dc:date>
<dc:identifier>doi:10.1101/2020.02.05.936120</dc:identifier>
<dc:title><![CDATA[mRNA stem-loops can pause the ribosome by hindering A-site tRNA binding]]></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/cgi/content/short/2020.03.10.986208v1?rss=1">
<title>
<![CDATA[
Detecting chromatin interactions along and between sister chromatids with SisterC 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.03.10.986208v1?rss=1"
</link>
<description><![CDATA[
Accurate chromosome segregation requires chromosome compaction with concordant disentanglement of the two sister chromatids. This process has been studied extensively by microscopy but has remained a challenge for genomic methods, such as Hi-C, because sister chromatids have identical DNA sequences. Here we describe SisterC, a chromosome conformation capture assay that can distinguish interactions between and within sister chromatids. The assay is based on BrdU incorporation during S-phase, which labels the newly replicated strands of the sister chromatids. This is followed by Hi-C, e.g. during different stages of mitosis, and the selective destruction of BrdU containing strands by UV/Hoechst treatment. After PCR amplification and sequencing of the remaining intact strands, this allows for the assignment of Hi-C products as inter- and intra-sister interactions by read orientation. We performed SisterC on mitotically arrested S. cerevisiae cells. As expected, we find prominent interactions and alignment of sister chromatids at their centromeres. Along the arms, sister chromatids are less precisely aligned with inter-sister connections every ~35kb. In many instances, inter-sister interactions do not involve the interaction of two identical loci but occur between cohesin binding sites that can be offset by 5 to 25kb. Along sister chromatids, extruding cohesin forms loops up to 50kb. Combined, SisterC allows the observation of the complex interplay between sister chromatid compaction and sister chromatid segregation as the cell transitions from late S-phase to mitosis. SisterC should be applicable to study mitotic events in a wide range of organisms and cell types.
]]></description>
<dc:creator>Oomen, M. E.</dc:creator>
<dc:creator>Hedger, A. K.</dc:creator>
<dc:creator>Watts, J. K.</dc:creator>
<dc:creator>Dekker, J.</dc:creator>
<dc:date>2020-03-11</dc:date>
<dc:identifier>doi:10.1101/2020.03.10.986208</dc:identifier>
<dc:title><![CDATA[Detecting chromatin interactions along and between sister chromatids with SisterC]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-03-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2020.08.03.235143v1?rss=1">
<title>
<![CDATA[
The RNA phosphatase PIR-1 regulates endogenous small RNA pathways in C. elegans 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.08.03.235143v1?rss=1"
</link>
<description><![CDATA[
Eukaryotic cells regulate 5 triphosphorylated (ppp-) RNAs to promote cellular functions and prevent recognition by antiviral RNA sensors. For example, RNA capping enzymes possess triphosphatase domains that remove the {gamma} phosphates of ppp-RNAs during RNA capping. Members of the closely related PIR1 family of RNA polyphosphatases remove both the {beta} and {gamma} phosphates from ppp-RNAs. Here we show that C. elegans PIR-1 dephosphorylates ppp-RNAs made by cellular RdRPs and is required for the maturation of 26G-RNAs, Dicer-dependent small RNAs that regulate thousands of genes during spermatogenesis and embryogenesis. PIR-1 also regulates the CSR-1 22G-RNA pathway and has critical functions in both somatic and germline development. Our findings suggest that PIR-1 modulates both Dicer-dependent and - independent Argonaute pathways, and provide insight into how cells and viruses use a conserved RNA phosphatase to regulate and respond to ppp-RNA species.
]]></description>
<dc:creator>Chaves, D. A.</dc:creator>
<dc:creator>Hui, D.</dc:creator>
<dc:creator>Li, L.</dc:creator>
<dc:creator>Moresco, J. J.</dc:creator>
<dc:creator>Oh, M. E.</dc:creator>
<dc:creator>Conte, D.</dc:creator>
<dc:creator>Yates, J. R.</dc:creator>
<dc:creator>Mello, C. C.</dc:creator>
<dc:creator>Gu, W.</dc:creator>
<dc:date>2020-08-04</dc:date>
<dc:identifier>doi:10.1101/2020.08.03.235143</dc:identifier>
<dc:title><![CDATA[The RNA phosphatase PIR-1 regulates endogenous small RNA pathways in C. elegans]]></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/cgi/content/short/2020.08.30.274597v1?rss=1">
<title>
<![CDATA[
Ribosome inhibition by C9ORF72-ALS/FTD-associated poly-PR and poly-GR proteins revealed by cryo-EM 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.08.30.274597v1?rss=1"
</link>
<description><![CDATA[
Toxic dipeptide repeat (DPR) proteins are produced from expanded G4C2 hexanucleotide repeats in the C9ORF72 gene, which cause amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Two DPR proteins, poly-PR and poly-GR, repress cellular translation but the molecular mechanism remains unknown. Here we show that poly-PR and poly-GR of [&ge;] 20 repeats inhibit the ribosomes peptidyl-transferase activity at nanomolar concentrations, comparable to specific translation inhibitors. High-resolution cryo-EM structures reveal that poly-PR and poly-GR block the polypeptide tunnel of the ribosome, extending into the peptidyl-transferase center. Consistent with these findings, the macrolide erythromycin, which binds in the tunnel, competes with the DPR proteins and restores peptidyl-transferase activity. Our results demonstrate that strong and specific binding of poly-PR and poly-GR in the ribosomal tunnel blocks translation, revealing the structural basis of their toxicity in C9ORF72-ALS/FTD.
]]></description>
<dc:creator>Loveland, A. B.</dc:creator>
<dc:creator>Svidritskiy, E.</dc:creator>
<dc:creator>Susorov, D.</dc:creator>
<dc:creator>Lee, S.</dc:creator>
<dc:creator>Park, A.</dc:creator>
<dc:creator>Demo, G.</dc:creator>
<dc:creator>Gao, F.-B.</dc:creator>
<dc:creator>Korostelev, A. A.</dc:creator>
<dc:date>2020-08-31</dc:date>
<dc:identifier>doi:10.1101/2020.08.30.274597</dc:identifier>
<dc:title><![CDATA[Ribosome inhibition by C9ORF72-ALS/FTD-associated poly-PR and poly-GR proteins revealed by cryo-EM]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2020.09.05.284349v1?rss=1">
<title>
<![CDATA[
CASCADES, a novel SOX2 super-enhancer associated long noncoding RNA, regulates cancer stem cell specification and differentiation in glioblastoma multiforme 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.09.05.284349v1?rss=1"
</link>
<description><![CDATA[
Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor in adults, with a median survival of just over one year. The failure of available treatments to achieve remission in patients with GBM has been attributed to the presence of cancer stem cells (CSCs), which are thought to play a central role in tumor development and progression and serve as a treatment-resistant cell repository capable of driving tumor recurrence; in fact, the property of "stemness" itself may be responsible for treatment resistance. In this study, we identify a novel lncRNA, Cancer stem cell associated distal enhancer of SOX2 (CASCADES) that functions as an epigenetic regulator in glioma CSCs (GSCs). CASCADES is expressed in IDH-wild type GBM and significantly enriched in GSCs. Knockdown of CASCADES in GSCs results in differentiation towards a neuronal lineage in a cell- and cancer-specific manner. Bioinformatics analysis reveals that CASCADES functions as a super-enhancer associated lncRNA epigenetic regulator of SOX2. Our findings identify CASCADES as a critical regulator of stemness in GSCs and represent a novel epigenetic and therapeutic target for disrupting the cancer stem cell compartment in GBM.
]]></description>
<dc:creator>Shahzad, U.</dc:creator>
<dc:creator>Li, C.</dc:creator>
<dc:creator>Johnston, M.</dc:creator>
<dc:creator>Wang, J. J.</dc:creator>
<dc:creator>Sabha, N.</dc:creator>
<dc:creator>Varn, F. S.</dc:creator>
<dc:creator>Riemenschneider, A.</dc:creator>
<dc:creator>Krumholtz, S.</dc:creator>
<dc:creator>Meda, P.</dc:creator>
<dc:creator>Smith, C.</dc:creator>
<dc:creator>Karamchandani, J.</dc:creator>
<dc:creator>Watts, J. K.</dc:creator>
<dc:creator>Verhaak, R. G. W.</dc:creator>
<dc:creator>Gallo, M.</dc:creator>
<dc:creator>Rutka, J. T.</dc:creator>
<dc:creator>Das, S.</dc:creator>
<dc:date>2020-09-06</dc:date>
<dc:identifier>doi:10.1101/2020.09.05.284349</dc:identifier>
<dc:title><![CDATA[CASCADES, a novel SOX2 super-enhancer associated long noncoding RNA, regulates cancer stem cell specification and differentiation in glioblastoma multiforme]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2020.09.08.287979v1?rss=1">
<title>
<![CDATA[
Terminal Modification, Sequence, and Length Determine Small RNA Stability in Animals 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.09.08.287979v1?rss=1"
</link>
<description><![CDATA[
In animals, piRNAs, siRNAs, and miRNAs silence transposons, fight viral infections, and regulate gene expression. piRNA biogenesis concludes with 3' terminal trimming and 2'-O-methylation. Both trimming and methylation influence piRNA stability. Here, we report that trimming and methylation protect mouse piRNAs from different decay mechanisms. In the absence of 2'-O-methylation, mouse piRNAs with extensive complementarity to long RNAs become unstable. In flies, 2'-O-methylation similarly protects both piRNAs and siRNAs from complementarity-dependent destabilization. Animal miRNAs are unmethylated, and complementarity-dependent destabilization helps explain differences in miRNA decay rates in both mice and flies. In contrast, trimming protects mouse piRNAs from a separate degradation pathway unaffected by target complementarity but sensitive to the 3' terminal, untrimmed sequence. Because distinct sets of mouse piRNAs are protected by each of these mechanisms, loss of both trimming and 2'-O-methylation causes the piRNA pathway to collapse, demonstrating that these two small RNA modifications collaborate to stabilize piRNAs.

HighlightsO_LI2'-O-methylation protects mouse and fly piRNAs from complementarity-dependent decay
C_LIO_LI2'-O-methylation protects fly siRNAs with extensive complementarity to long RNAs
C_LIO_LIComplementarity to long RNAs predicts the half-life of fly and mouse miRNAs
C_LIO_LIMouse pre-piRNA decay reflects both pre-piRNA sequence and PIWI protein identity
C_LI
]]></description>
<dc:creator>Gainetdinov, I.</dc:creator>
<dc:creator>Colpan, C.</dc:creator>
<dc:creator>Cecchini, K.</dc:creator>
<dc:creator>Albosta, P.</dc:creator>
<dc:creator>Jouravleva, K.</dc:creator>
<dc:creator>Vega-Badillo, J.</dc:creator>
<dc:creator>Lee, Y.</dc:creator>
<dc:creator>Ozata, D.</dc:creator>
<dc:creator>Zamore, P. D.</dc:creator>
<dc:date>2020-09-08</dc:date>
<dc:identifier>doi:10.1101/2020.09.08.287979</dc:identifier>
<dc:title><![CDATA[Terminal Modification, Sequence, and Length Determine Small RNA Stability in Animals]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-09-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2020.08.17.253955v1?rss=1">
<title>
<![CDATA[
PIE-1 promotes SUMOylation and activation of HDAC1 during the C. elegans oogenesis 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.08.17.253955v1?rss=1"
</link>
<description><![CDATA[
Germlines shape and balance heredity, integrating and regulating information from both parental and foreign sources. Insights into how the germline handles information have come from the identification of factors that specify or maintain the germline fate. In early C. elegans embryos, the CCCH zinc-finger protein PIE-1 localizes to the germline where it prevents somatic differentiation programs. Here we show that PIE-1 also functions in the meiotic ovary where it becomes SUMOylated and engages the SUMO-conjugating machinery. Using whole-proteome mass spectrometry to detect SUMO-conjugated proteins, we identify HDAC SUMOylation as a target of PIE-1. Our findings suggest that SUMOylation activates HDAC, lowering histone acetylation and enhancing Argonaute-mediated surveillance in the germline.
]]></description>
<dc:creator>Kim, H.</dc:creator>
<dc:creator>Ding, Y.-H.</dc:creator>
<dc:creator>Lu, S.</dc:creator>
<dc:creator>Zuo, M.-Q.</dc:creator>
<dc:creator>Conte, D.</dc:creator>
<dc:creator>Dong, M.-Q.</dc:creator>
<dc:creator>Mello, C.</dc:creator>
<dc:date>2020-08-17</dc:date>
<dc:identifier>doi:10.1101/2020.08.17.253955</dc:identifier>
<dc:title><![CDATA[PIE-1 promotes SUMOylation and activation of HDAC1 during the C. elegans oogenesis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2020.08.17.254466v1?rss=1">
<title>
<![CDATA[
HDAC1 SUMOylation promotes Argonaute directed transcriptional silencing in C. elegans 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.08.17.254466v1?rss=1"
</link>
<description><![CDATA[
Eukaryotic cells use guided search to coordinately control dispersed genetic elements. The transitive effectors of these mechanisms, Argonaute proteins and their small-RNA co-factors, engage nascent RNAs and chromatin-associated proteins to direct transcriptional silencing. The small ubiquitin-like modifier (SUMO) has been shown to promote the induction and maintenance of silent chromatin (called heterochromatin) in yeast, plants, and animals. Here we show that Argonaute-directed transcriptional silencing in C. elegans requires SUMOylation of the type 1 histone deacetylase HDA-1. SUMOylation of HDA-1 promotes interactions with components of the nucleosome remodeling and deacetylase (NuRD) complex and with the nuclear Argonaute HRDE-1/WAGO-9. Our findings suggest how HDAC1 SUMOylation promotes the association of HDAC and other chromatin remodeling factors with a nuclear Argonaute in order to initiate de novo heterochromatin silencing.
]]></description>
<dc:creator>Kim, H.</dc:creator>
<dc:creator>Ding, Y.-H.</dc:creator>
<dc:creator>Zhang, G.</dc:creator>
<dc:creator>Yan, Y.-H.</dc:creator>
<dc:creator>Conte, D.</dc:creator>
<dc:creator>Dong, M.-Q.</dc:creator>
<dc:creator>Mello, C.</dc:creator>
<dc:date>2020-08-17</dc:date>
<dc:identifier>doi:10.1101/2020.08.17.254466</dc:identifier>
<dc:title><![CDATA[HDAC1 SUMOylation promotes Argonaute directed transcriptional silencing in C. elegans]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-08-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2020.10.09.333997v1?rss=1">
<title>
<![CDATA[
Precision Cas9 Genome Editing in vivo with All-in-one, Self-targeting AAV Vectors 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.10.09.333997v1?rss=1"
</link>
<description><![CDATA[
Adeno-associated virus (AAV) vectors are important delivery platforms for therapeutic genome editing but are severely constrained by cargo limits, especially for large effectors like Cas9s. Simultaneous delivery of multiple vectors can limit dose and efficacy and increase safety risks. The use of compact effectors has enabled single-AAV delivery of Cas9s with 1-3 guides for edits that use end-joining repair pathways, but many precise edits that correct disease-causing mutations in vivo require homology-directed repair (HDR) templates. Here, we describe single-vector, [~]4.8-kb AAV platforms that express Nme2Cas9 and either two sgRNAs to produce segmental deletions, or a single sgRNA with an HDR template. We also examine the utility of Nme2Cas9 target sites in the vector for self-inactivation. We demonstrate that these platforms can effectively treat two disease models [type I hereditary tyrosinemia (HT-I) and mucopolysaccharidosis type I (MPS-I)] in mice. These results will enable single-vector AAVs to achieve diverse therapeutic genome editing outcomes.
]]></description>
<dc:creator>Ibraheim, R.</dc:creator>
<dc:creator>Tai, P. W. L.</dc:creator>
<dc:creator>Mir, A.</dc:creator>
<dc:creator>Javeed, N.</dc:creator>
<dc:creator>Wang, J.</dc:creator>
<dc:creator>Rodriguez, T. C.</dc:creator>
<dc:creator>Nelson, S.</dc:creator>
<dc:creator>Khokhar, E.</dc:creator>
<dc:creator>Mintzer, E.</dc:creator>
<dc:creator>Maitland, S.</dc:creator>
<dc:creator>Cao, Y.</dc:creator>
<dc:creator>Tsagkaraki, E.</dc:creator>
<dc:creator>Wolfe, S. A.</dc:creator>
<dc:creator>Wang, D.</dc:creator>
<dc:creator>Pai, A. A.</dc:creator>
<dc:creator>Xue, W.</dc:creator>
<dc:creator>Gao, G.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:date>2020-10-09</dc:date>
<dc:identifier>doi:10.1101/2020.10.09.333997</dc:identifier>
<dc:title><![CDATA[Precision Cas9 Genome Editing in vivo with All-in-one, Self-targeting AAV Vectors]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-09</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2020.10.13.337923v1?rss=1">
<title>
<![CDATA[
CRISPR-enhanced human adipocyte 'browning' as cell therapy for metabolic disease 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.10.13.337923v1?rss=1"
</link>
<description><![CDATA[
Obesity and type 2 diabetes (T2D) are associated with poor tissue responses to insulin1,2, disturbances in glucose and lipid fluxes3-5 and comorbidities including steatohepatitis6 and cardiovascular disease7,8. Despite extensive efforts at prevention and treatment9,10, diabetes afflicts over 400 million people worldwide11. Whole body metabolism is regulated by adipose tissue depots12-14, which include both lipid-storing white adipocytes and less abundant "brown" and "brite/beige" adipocytes that express thermogenic uncoupling protein UCP1 and secrete factors favorable to metabolic health15-18. Application of clustered regularly interspaced short palindromic repeats (CRISPR) gene editing19,20 to enhance "browning" of white adipose tissue is an attractive therapeutic approach to T2D. However, the problems of cell-selective delivery, immunogenicity of CRISPR reagents and long term stability of the modified adipocytes are formidable. To overcome these issues, we developed methods that deliver complexes of SpyCas9 protein and sgRNA ex vivo to disrupt the thermogenesis suppressor gene NRIP121,22 with near 100% efficiency in human or mouse adipocytes. NRIP1 gene disruption at discrete loci strongly ablated NRIP1 protein and upregulated expression of UCP1 and beneficial secreted factors, while residual Cas9 protein and sgRNA were rapidly degraded. Implantation of the CRISPR-enhanced human or mouse brown-like adipocytes into high fat diet fed mice decreased adiposity and liver triglycerides while enhancing glucose tolerance compared to mice implanted with unmodified adipocytes. These findings advance a therapeutic strategy to improve metabolic homeostasis through CRISPR-based genetic modification of human adipocytes without exposure of the recipient to immunogenic Cas9 or delivery vectors.
]]></description>
<dc:creator>Tsagkaraki, E.</dc:creator>
<dc:creator>Nicoloro, S.</dc:creator>
<dc:creator>De Souza, T.</dc:creator>
<dc:creator>Solivan-Rivera, J.</dc:creator>
<dc:creator>Desai, A.</dc:creator>
<dc:creator>Shen, Y.</dc:creator>
<dc:creator>Kelly, M.</dc:creator>
<dc:creator>Guilherme, A.</dc:creator>
<dc:creator>Henriques, F.</dc:creator>
<dc:creator>Ibraheim, R.</dc:creator>
<dc:creator>Amrani, N.</dc:creator>
<dc:creator>Luk, K.</dc:creator>
<dc:creator>Maitland, S.</dc:creator>
<dc:creator>Friedline, R. H.</dc:creator>
<dc:creator>Tauer, L.</dc:creator>
<dc:creator>Hu, X.</dc:creator>
<dc:creator>Kim, J. K.</dc:creator>
<dc:creator>Wolfe, S. A.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:creator>Corvera, S.</dc:creator>
<dc:creator>Czech, M. P.</dc:creator>
<dc:date>2020-10-13</dc:date>
<dc:identifier>doi:10.1101/2020.10.13.337923</dc:identifier>
<dc:title><![CDATA[CRISPR-enhanced human adipocyte 'browning' as cell therapy for metabolic disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2020.10.16.341222v1?rss=1">
<title>
<![CDATA[
Translation-dependent and independent mRNA decay occur through mutually exclusive pathways that are defined by ribosome density during T Cell activation. 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.10.16.341222v1?rss=1"
</link>
<description><![CDATA[
mRNA translation and degradation are strongly interconnected processes that participate in the fine tuning of gene expression. Particularly, targeting mRNAs to translation-dependent degradation (TDD) could attenuate protein expression by making any increase in mRNA translation self-limiting. However, the extent to which TDD is a general mechanism for limiting protein expression is currently unknown. Here we describe a comprehensive analysis of basal and signal-induced TDD in mouse primary CD4 T cells. Our data indicate that most cellular transcripts are decayed to some extent in a translation-dependent manner, both in resting and activated cells. Our analysis further identifies the length of untranslated regions, the density of ribosomes and the GC content of the coding region as major determinants of TDD magnitude. Consistent with this, all transcripts that undergo changes in ribosome density upon T cell activation display a corresponding change in their TDD level. Surprisingly, the amplitude of translation-independent mRNA decay (TID) appears as a mirror image of TDD. Moreover, TID also responds to changes in ribosome density upon T cell activation but in the opposite direction from the one observed for TDD. Our data demonstrate a strong interconnection between mRNA translation and decay in mammalian cells. Furthermore, they indicate that ribosome density is a major determinant of the pathway by which transcripts are degraded within cells.
]]></description>
<dc:creator>Mercier, B. C.</dc:creator>
<dc:creator>Labaronne, E.</dc:creator>
<dc:creator>Cluet, D.</dc:creator>
<dc:creator>Bicknell, A.</dc:creator>
<dc:creator>Corbin, A.</dc:creator>
<dc:creator>Guiguettaz, L.</dc:creator>
<dc:creator>Aube, F.</dc:creator>
<dc:creator>Modolo, L.</dc:creator>
<dc:creator>Auboeuf, D.</dc:creator>
<dc:creator>Moore, M. J.</dc:creator>
<dc:creator>Ricci, E. P.</dc:creator>
<dc:date>2020-10-17</dc:date>
<dc:identifier>doi:10.1101/2020.10.16.341222</dc:identifier>
<dc:title><![CDATA[Translation-dependent and independent mRNA decay occur through mutually exclusive pathways that are defined by ribosome density during T Cell activation.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-10-17</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/847004v1?rss=1">
<title>
<![CDATA[
Deep sequencing of pre-translational mRNPs reveals hidden flux through evolutionarily conserved AS-NMD pathways 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/847004v1?rss=1"
</link>
<description><![CDATA[
BackgroundAlternative splicing (AS), which generates multiple mRNA isoforms from single genes, is crucial for the regulation of eukaryotic gene expression. The flux through competing AS pathways cannot be determined by traditional RNA-Seq, however, because different mRNA isoforms can have widely differing decay rates. Indeed, some mRNA isoforms with extremely short half-lives, such as those subject to translation-dependent nonsense-mediated decay (AS-NMD), may be completely overlooked in even the most extensive RNA-Seq analyses.

ResultsRNA immunoprecipitation in tandem (RIPiT) of exon junction complex (EJC) components allows for purification of post-splicing mRNA-protein particles (mRNPs) not yet subject to translation (pre-translational mRNPs) and, therefore, translation-dependent mRNA decay. Here we compared EJC RIPiT-Seq to whole cell RNA-Seq data from HEK293 cells. Consistent with expectation, the flux through known AS-NMD pathways is substantially higher than that captured by RNA-Seq. Our EJC RIPiT-Seq also definitively demonstrates that the splicing machinery itself has no ability to detect reading frame. We identified thousands of previously unannotated splicing events; while many can be attributed to "splicing noise", others are evolutionarily-conserved events that produce new AS-NMD isoforms likely involved in maintenance of protein homeostasis. Several of these occur in genes whose overexpression has been linked to poor cancer prognosis.

ConclusionsDeep sequencing of RNAs in post-splicing, pre-translational mRNPs provides a means to identify and quantify splicing events without the confounding influence of differential mRNA decay. For many known AS-NMD targets, the NMD-linked AS pathway predominates. EJC RIPiT-Seq also enabled identification of numerous conserved but previously unannotated AS-NMD events.
]]></description>
<dc:creator>Kovalak, C. A.</dc:creator>
<dc:creator>Moore, M. J.</dc:creator>
<dc:creator>Metkar, M.</dc:creator>
<dc:date>2019-11-19</dc:date>
<dc:identifier>doi:10.1101/847004</dc:identifier>
<dc:title><![CDATA[Deep sequencing of pre-translational mRNPs reveals hidden flux through evolutionarily conserved AS-NMD pathways]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2019-11-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2020.12.29.424751v1?rss=1">
<title>
<![CDATA[
Structural basis for +1 ribosomal frameshifting during EF-G-catalyzed translocation 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.12.29.424751v1?rss=1"
</link>
<description><![CDATA[
Frameshifting of mRNA during translation provides a strategy to expand the coding repertoire of cells and viruses. Where and how in the elongation cycle +1-frameshifting occurs remains poorly understood. We captured six [~]3.5-[A]-resolution cryo-EM structures of ribosomal elongation complexes formed with the GTPase elongation factor G (EF-G). Three structures with a +1-frameshifting-prone mRNA reveal that frameshifting takes place during translocation of tRNA and mRNA. Prior to EF-G binding, the pre-translocation complex features an in-frame tRNA-mRNA pairing in the A site. In the partially translocated structure with EF-G, the tRNA shifts to the +1-frame codon near the P site, whereas the freed mRNA base bulges between the P and E sites and stacks on the 16S rRNA nucleotide G926. The ribosome remains frameshifted in the nearly post-translocation state. Our findings demonstrate that the ribosome and EF-G cooperate to induce +1 frameshifting during mRNA translocation.
]]></description>
<dc:creator>Demo, G.</dc:creator>
<dc:creator>Loveland, A. B.</dc:creator>
<dc:creator>Svidritskiy, E.</dc:creator>
<dc:creator>Gamper, H. B.</dc:creator>
<dc:creator>Hou, Y.-M.</dc:creator>
<dc:creator>Korostelev, A. A.</dc:creator>
<dc:date>2020-12-29</dc:date>
<dc:identifier>doi:10.1101/2020.12.29.424751</dc:identifier>
<dc:title><![CDATA[Structural basis for +1 ribosomal frameshifting during EF-G-catalyzed translocation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-12-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/354480v1?rss=1">
<title>
<![CDATA[
5′ Modifications Improve Potency and Efficacy of DNA Donors for Precision Genome Editing 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/354480v1?rss=1"
</link>
<description><![CDATA[
Nuclease-directed genome editing is a powerful tool for investigating physiology and has great promise as a therapeutic approach to correct mutations that cause disease. In its most precise form, genome editing can use cellular homology-directed repair (HDR) pathways to insert information from an exogenously supplied DNA repair template (donor) directly into a targeted genomic location. Unfortunately, particularly for long insertions, toxicity and delivery considerations associated with repair template DNA can limit HDR efficacy. Here, we explore chemical modifications to both double-stranded and single-stranded DNA-repair templates. We describe 5'-terminal modifications, including in its simplest form the incorporation of triethylene glycol (TEG) moieties, that consistently increase the frequency of precision editing in the germlines of three animal models (Caenorhabditis elegans, zebrafish, mice) and in cultured human cells.
]]></description>
<dc:creator>Ghanta, K. S.</dc:creator>
<dc:creator>Dokshin, G. A.</dc:creator>
<dc:creator>Mir, A.</dc:creator>
<dc:creator>Krishnamurthy, P. M.</dc:creator>
<dc:creator>Gneid, H.</dc:creator>
<dc:creator>Edraki, A.</dc:creator>
<dc:creator>Watts, J. K.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:creator>Mello, C. C.</dc:creator>
<dc:date>2018-06-22</dc:date>
<dc:identifier>doi:10.1101/354480</dc:identifier>
<dc:title><![CDATA[5′ Modifications Improve Potency and Efficacy of DNA Donors for Precision Genome Editing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2018-06-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2021.02.14.431096v1?rss=1">
<title>
<![CDATA[
Quantifying and Mitigating Motor Phenotypes Induced by Antisense Oligonucleotides in the Central Nervous System 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.02.14.431096v1?rss=1"
</link>
<description><![CDATA[
Antisense oligonucleotides (ASOs) are emerging as a promising class of therapeutics for neurological diseases. When injected directly into the cerebrospinal fluid, ASOs distribute broadly across brain regions and exert long-lasting therapeutic effects. However, many phosphorothioate (PS)-modified gapmer ASOs show transient motor phenotypes when injected into the cerebrospinal fluid, ranging from reduced motor activity to ataxia or acute seizure-like phenotypes. The effect of sugar and phosphate modifications on these phenotypes has not previously been systematically studied. Using a behavioral scoring assay customized to reflect the timing and nature of these effects, we show that both sugar and phosphate modifications influence acute motor phenotypes. Among sugar analogues, PS-DNA induces the strongest motor phenotype while 2-substituted RNA modifications improve the tolerability of PS-ASOs. This helps explain why gapmer ASOs have been more challenging to develop clinically relative to steric blocker ASOs, which have a reduced tendency to induce these effects. Reducing the PS content of gapmer ASOs, which contain a stretch of PS-DNA, improves their toxicity profile, but in some cases also reduces their efficacy or duration of effect. Reducing PS content improved the acute tolerability of ASOs in both mice and sheep. We show that this acute toxicity is not mediated by the major nucleic acid sensing innate immune pathways. Formulating ASOs with calcium ions before injecting into the CNS further improved their tolerability, but through a mechanism at least partially distinct from the reduction of PS content. Overall, our work identifies and quantifies an understudied aspect of oligonucleotide toxicology in the CNS, explores its mechanism, and presents platform-level medicinal chemistry approaches that improve tolerability of this class of compounds.
]]></description>
<dc:creator>Moazami, M. P.</dc:creator>
<dc:creator>Rembetsy-Brown, J. M.</dc:creator>
<dc:creator>Wang, F.</dc:creator>
<dc:creator>Krishnamurthy, P. M.</dc:creator>
<dc:creator>Weiss, A.</dc:creator>
<dc:creator>Marosfoi, M.</dc:creator>
<dc:creator>King, R. M.</dc:creator>
<dc:creator>Motwani, M.</dc:creator>
<dc:creator>Gray-Edwards, H.</dc:creator>
<dc:creator>Fitzgerald, K. A.</dc:creator>
<dc:creator>Brown, R. H.</dc:creator>
<dc:creator>Watts, J. K.</dc:creator>
<dc:date>2021-02-15</dc:date>
<dc:identifier>doi:10.1101/2021.02.14.431096</dc:identifier>
<dc:title><![CDATA[Quantifying and Mitigating Motor Phenotypes Induced by Antisense Oligonucleotides in the Central Nervous System]]></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/cgi/content/short/2020.12.15.422970v1?rss=1">
<title>
<![CDATA[
Improved prime editors enable pathogenic allele correction and cancer modelling in adult mice 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.12.15.422970v1?rss=1"
</link>
<description><![CDATA[
Prime editors (PEs) mediate genome modification without utilizing double-stranded DNA breaks or exogenous donor DNA as a template. PEs facilitate nucleotide substitutions or local insertions or deletions within the genome based on the template sequence encoded within the prime editing guide RNA (pegRNA). However, the efficacy of prime editing in adult mice has not been established. Here we report an NLS-optimized SpCas9-based prime editor that improves genome editing efficiency in both fluorescent reporter cells and at endogenous loci in cultured cell lines. Using this genome modification system, we could also seed tumor formation through somatic cell editing in the adult mouse. Finally, we successfully utilize dual adeno-associated virus (AAVs) for the delivery of a split-intein prime editor and demonstrate that this system enables the correction of a pathogenic mutation in the mouse liver. Our findings further establish the broad potential of this genome editing technology for the directed installation of sequence modifications in vivo, with important implications for disease modeling and correction.
]]></description>
<dc:creator>Liu, P.</dc:creator>
<dc:creator>Liang, S.</dc:creator>
<dc:creator>Zheng, C.</dc:creator>
<dc:creator>Mintzer, E.</dc:creator>
<dc:creator>Zhao, Y. G.</dc:creator>
<dc:creator>Ponnienselvan, K.</dc:creator>
<dc:creator>Mir, A.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:creator>Gao, G.</dc:creator>
<dc:creator>Flotte, T. R.</dc:creator>
<dc:creator>Wolfe, S.</dc:creator>
<dc:creator>Xue, W.</dc:creator>
<dc:date>2020-12-16</dc:date>
<dc:identifier>doi:10.1101/2020.12.15.422970</dc:identifier>
<dc:title><![CDATA[Improved prime editors enable pathogenic allele correction and cancer modelling in adult mice]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-12-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2021.04.04.438419v1?rss=1">
<title>
<![CDATA[
The testis-specific transcription factor TCFL5 responds to A MYBto elaborate the male meiotic program in placental mammals 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.04.04.438419v1?rss=1"
</link>
<description><![CDATA[
In male mice, the transcription factor (TF) A-MYB initiates reprogramming of gene expression after spermatogonia enter meiosis. We report that A-MYB activates Tcfl5, a testis-specific TF first produced in pachytene spermatocytes. Subsequently, A-MYB and TCFL5 reciprocally reinforce their own transcription to establish an extensive circuit that regulates meiosis. TCFL5 promotes transcription of genes required for mRNA turnover, pachytene piRNA production, meiotic exit, and spermiogenesis. This transcriptional architecture is conserved in rhesus macaque, suggesting TCFL5 plays a central role in meiosis and spermiogenesis in placental mammals. Tcfl5em1/em1 mutants are sterile, and spermatogenesis arrests at the mid- or late-pachytene stage of meiosis.
]]></description>
<dc:creator>Ozata, D. M.</dc:creator>
<dc:creator>Yu, T.</dc:creator>
<dc:creator>Cecchini, K.</dc:creator>
<dc:creator>Mou, H.</dc:creator>
<dc:creator>Arif, A.</dc:creator>
<dc:creator>Colpan, C.</dc:creator>
<dc:creator>Adriano Biasini, A.</dc:creator>
<dc:creator>Gainetdinov, I.</dc:creator>
<dc:creator>de Rooij, D. G.</dc:creator>
<dc:creator>Weng, Z.</dc:creator>
<dc:creator>Zamore, P.</dc:creator>
<dc:date>2021-04-05</dc:date>
<dc:identifier>doi:10.1101/2021.04.04.438419</dc:identifier>
<dc:title><![CDATA[The testis-specific transcription factor TCFL5 responds to A MYBto elaborate the male meiotic program in placental mammals]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2021.04.20.440648v1?rss=1">
<title>
<![CDATA[
Locating Macromolecular Assemblies in Cells by 2D Template Matching with cisTEM 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.04.20.440648v1?rss=1"
</link>
<description><![CDATA[
Over the last decade, single-particle electron cryo-microscopy has become one of the main techniques contributing to the growing library of high-resolution structures of macromolecules and their assemblies. For a full understanding of molecular mechanisms, however, it is important to place them into the broader context of a cell. Traditionally, this context can be visualized in 3D by electron cryo-tomography, and more recently, has also been studied by template matching of 2D images of cells and viruses. A current limitation of the latter approach is the high computational cost that limits the throughput and widespread adoption of this method. We describe here a GPU-accelerated implementation of 2D template matching in the image processing software cisTEM that allows for easy scaling and improves the accessibility of this approach. We apply 2D template matching to identify ribosomes in images of frozen-hydrated Mycoplasma pneumoniae cells and demonstrate that it can function as a versatile tool for in situ visual proteomics and in situ structure determination. We compare the results with 3D template matching of tomograms acquired on identical sample locations. We identify strengths and weaknesses of both techniques which offer complementary information about target localization and identity.
]]></description>
<dc:creator>Lucas, B. A.</dc:creator>
<dc:creator>Himes, B. A.</dc:creator>
<dc:creator>Xue, L.</dc:creator>
<dc:creator>Grant, T.</dc:creator>
<dc:creator>Mahamid, J.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:date>2021-04-21</dc:date>
<dc:identifier>doi:10.1101/2021.04.20.440648</dc:identifier>
<dc:title><![CDATA[Locating Macromolecular Assemblies in Cells by 2D Template Matching with cisTEM]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-04-21</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2021.05.04.442675v1?rss=1">
<title>
<![CDATA[
The tiny, conserved zinc-finger protein GTSF1helps PIWI proteins achieve their full catalytic potential 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.05.04.442675v1?rss=1"
</link>
<description><![CDATA[
Argonaute proteins use nucleic acid guides to find and bind specific DNA or RNA target sequences. Argonaute proteins can be found in all kingdoms of life, and play diverse biological functions including genome defense, gene regulation, and chromosome partitioning. Many Argonautes retain their ancestral endoribonuclease activity, cleaving the phosphodiester bond between target nucleotides t10 and t11. In animals, a specialized class of Argonautes, the PIWI proteins, use 21-35 nt PIWI-interacting RNAs (piRNAs) to direct transposon silencing, protect the germline genome, and regulate gene expression during gametogenesis1. The piRNA pathway is required for fertility in one or both sexes of nearly all animals. Both piRNA production and function require RNA cleavage catalyzed by PIWI proteins. Spermatogenesis in mice and other placental mammals requires three distinct, developmentally regulated PIWI proteins: MIWI (PIWIL1), MILI (PIWIL2), and MIWI2 (PIWIL4)2-4. The piRNA-guided endoribonuclease activities of MIWI and MILI are essential to produce functional sperm5, 6. piRNA-directed silencing in mice and insects also requires Gametocyte-Specific Factor 1 (GTSF1), a PIWI-associated protein of unknown function7-12. Here, we report that GTSF1 potentiates the weak, intrinsic, piRNA-directed RNA cleavage activities of PIWI proteins, transforming them into efficient endoribonucleases. GTSF1 represents the first example of an auxiliary protein that potentiates the catalytic activity of an Argonaute protein.
]]></description>
<dc:creator>Arif, A.</dc:creator>
<dc:creator>Ozata, D. M.</dc:creator>
<dc:creator>Andersson, C.</dc:creator>
<dc:creator>Izumi, N.</dc:creator>
<dc:creator>Tomari, Y.</dc:creator>
<dc:creator>Zamore, P. D.</dc:creator>
<dc:date>2021-05-04</dc:date>
<dc:identifier>doi:10.1101/2021.05.04.442675</dc:identifier>
<dc:title><![CDATA[The tiny, conserved zinc-finger protein GTSF1helps PIWI proteins achieve their full catalytic potential]]></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/cgi/content/short/2021.02.19.431636v1?rss=1">
<title>
<![CDATA[
Cryo-TEM simulations of amorphous radiation-sensitive samples using multislice wave propagation. 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.02.19.431636v1?rss=1"
</link>
<description><![CDATA[
Image simulation plays a central role in the development and practice of high-resolution electron microscopy, including transmission electron microscopy of frozen-hydrated specimens (cryo-EM). Simulating images with contrast that matches the contrast observed in experimental images remains challenging, especially for amorphous samples. Current state-of-the-art simulators apply post hoc scaling to approximate empirical solvent contrast, attenuated image intensity due to specimen thickness, and amplitude contrast. This practice fails for images that require spatially variable scaling, e.g., simulations of a crowded or cellular environment. Modeling both the signal and the noise accurately is necessary to simulate images of biological specimens with contrast that is correct on an absolute scale. The "Frozen-Plasmon" method is introduced which explicitly models spatially variable inelastic scattering processes in cryo-EM specimens. This approach produces amplitude contrast that depends on the atomic composition of the specimen, reproduces the total inelastic mean free path as observed experimentally, and allows for the incorporation of radiation damage in the simulation. These improvements are quantified using the matched-filter concept to compare simulation and experiment. The Frozen-Plasmon method, in combination with a new mathematical formulation for accurately sampling the tabulated atomic scattering potentials onto a Cartesian grid, is implemented in the open-source software package cisTEM.
]]></description>
<dc:creator>Himes, B. A.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:date>2021-02-19</dc:date>
<dc:identifier>doi:10.1101/2021.02.19.431636</dc:identifier>
<dc:title><![CDATA[Cryo-TEM simulations of amorphous radiation-sensitive samples using multislice wave propagation.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-02-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2021.05.12.443800v1?rss=1">
<title>
<![CDATA[
Programming large target genomic deletion and concurrent insertion via a prime editing-based method: PEDAR 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.05.12.443800v1?rss=1"
</link>
<description><![CDATA[
Genomic insertions, duplications, and insertion/deletions (indels) account for ~14% of human pathogenic mutations. Current gene editing methods cannot accurately or efficiently correct these abnormal genomic rearrangements, especially larger alterations (>100 bp). Thus, developing a method to accurately delete insertions/duplications and repair the deletion junction could improve the scope of gene therapies. Here, we engineer a novel gene editor, PE-Cas9, by conjugating Cas9 nuclease to reverse transcriptase. Combined with two prime editing guide RNAs (pegRNAs) targeting complementary DNA strands, PE-Cas9 can direct the replacement of a genomic fragment, ranging from to ~1-kb to >10-kb, with a desired sequence at the target site without requiring an exogenous DNA template. In a reporter cell line, this PE-Cas9-based deletion and repair (PEDAR) method restored mCherry expression through in-frame deletion of a disrupted GFP sequence. We further show that PEDAR efficiency could be enhanced by using pegRNAs with high cleavage activity or increasing transfection efficiency. In tyrosinemia mice, PEDAR removed a 1.38-kb pathogenic insertion within the Fah gene and precisely repaired the deletion junction to restore FAH expression in liver. This study highlights PEDAR as a tool for correcting pathogenic mutations.
]]></description>
<dc:creator>Jiang, T.</dc:creator>
<dc:creator>Zhang, X.-O.</dc:creator>
<dc:creator>Weng, Z.</dc:creator>
<dc:creator>Xue, W.</dc:creator>
<dc:date>2021-05-13</dc:date>
<dc:identifier>doi:10.1101/2021.05.12.443800</dc:identifier>
<dc:title><![CDATA[Programming large target genomic deletion and concurrent insertion via a prime editing-based method: PEDAR]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-13</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2021.05.27.446076v1?rss=1">
<title>
<![CDATA[
Widespread occurrence of hybrid internal-terminal exons in human transcriptomes 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.05.27.446076v1?rss=1"
</link>
<description><![CDATA[
Alternative RNA processing is a major mechanism for diversifying the human transcriptome. Messenger RNA isoform differences are predominantly driven by alternative first exons, cassette internal exons and alternative last exons. Despite the importance of classifying exons to understand isoform structure, there is a lack of tools to look at isoform-specific exon usage using RNA-sequencing data. We recently observed that alternative transcription start sites often arise near annotated internal exons, creating "hybrid" exons that can be used as both first or internal exons. To investigate the creation of hybrid exons, we built the HIT (Hybrid-Internal-Terminal) exon pipeline that systematically classifies exons depending on their isoform-specific usage. Using a combination of junction reads coverage and probabilistic modeling, the HIT index identified thousands of hybrid first-internal and internal-last exons that were previously misclassified. Hybrid exons are enriched in long genes with at least ten internal exons, have longer flanking introns and strong splice sites. The usage of hybrid exons varies considerably across human tissues, but they are predominantly used in brain, testis and colon cells. Notably, genes involved in RNA splicing have the highest fraction of intra-tissue hybrid exons. Further, we found more than 100,000 inter-tissue hybrid exons that changed from internal to terminal exons across tissues. By developing the first method that can classify exons according to their isoform contexts, our findings demonstrate the existence of hybrid exons, expand the repertoire of tissue-specific terminal exons and uncover unexpected complexities of the human transcriptome.
]]></description>
<dc:creator>Fiszbein, A.</dc:creator>
<dc:creator>McGurk, M.</dc:creator>
<dc:creator>Calvo-Roitberg, E.</dc:creator>
<dc:creator>Kim, G.</dc:creator>
<dc:creator>Burge, C.</dc:creator>
<dc:creator>Pai, A. A.</dc:creator>
<dc:date>2021-05-29</dc:date>
<dc:identifier>doi:10.1101/2021.05.27.446076</dc:identifier>
<dc:title><![CDATA[Widespread occurrence of hybrid internal-terminal exons in human transcriptomes]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2021.05.31.446434v1?rss=1">
<title>
<![CDATA[
Time-resolved cryo-EM visualizes ribosomal translocation with EF-G and GTP 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.05.31.446434v1?rss=1"
</link>
<description><![CDATA[
During translation, a conserved GTPase elongation factor--EF-G in bacteria or eEF2 in eukaryotes--translocates tRNA and mRNA through the ribosome. EF-G has been proposed to act as a flexible motor that propels tRNA and mRNA movement, as a rigid pawl that biases unidirectional translocation resulting from ribosome rearrangements, or by various combinations of motor- and pawl-like mechanisms. Using time-resolved cryo-EM, we visualized GTP-catalyzed translocation without inhibitors, capturing elusive structures of ribosome*EF-G intermediates at near-atomic resolution. Prior to translocation, EF-G binds near peptidyl-tRNA, while the rotated 30S subunit stabilizes the EF-G GTPase center. Reverse 30S rotation releases Pi and translocates peptidyl-tRNA and EF-G by [~]20 [A]. An additional 4-[A] translocation initiates EF-G dissociation from a transient ribosome state with highly swiveled 30S head. The structures visualize how nearly rigid EF-G rectifies inherent and spontaneous ribosomal dynamics into tRNA-mRNA translocation, whereas GTP hydrolysis and Pi release drive EF-G dissociation.
]]></description>
<dc:creator>Carbone, C. E.</dc:creator>
<dc:creator>Loveland, A. B.</dc:creator>
<dc:creator>Gamper, H.</dc:creator>
<dc:creator>Hou, Y.-M.</dc:creator>
<dc:creator>Demo, G.</dc:creator>
<dc:creator>Korostelev, A. A.</dc:creator>
<dc:date>2021-05-31</dc:date>
<dc:identifier>doi:10.1101/2021.05.31.446434</dc:identifier>
<dc:title><![CDATA[Time-resolved cryo-EM visualizes ribosomal translocation with EF-G and GTP]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2021.04.25.441198v1?rss=1">
<title>
<![CDATA[
Towards community-driven metadata standards for light microscopy: tiered specifications extending the OME model 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.04.25.441198v1?rss=1"
</link>
<description><![CDATA[
1 -Digital light microscopy provides powerful tools for quantitatively probing the real-time dynamics of subcellular structures. While the power of modern microscopy techniques is undeniable, rigorous record-keeping and quality control are required to ensure that imaging data may be properly interpreted (quality), reproduced (reproducibility), and used to extract reliable information and scientific knowledge which can be shared for further analysis (value). Keeping notes on microscopy experiments and quality control procedures ought to be straightforward, as the microscope is a machine whose components are defined and the performance measurable. Nevertheless, to this date, no universally adopted community-driven specifications exist that delineate the required information about the microscope hardware and acquisition settings (i.e., microscopy "data provenance" metadata) and the minimally accepted calibration metrics (i.e., microscopy quality control metadata) that should be automatically recorded by both commercial microscope manufacturers and customized microscope developers. In the absence of agreed guidelines, it is inherently difficult for scientists to create comprehensive records of imaging experiments and ensure the quality of resulting image data or for manufacturers to incorporate standardized reporting and performance metrics. To add to the confusion, microscopy experiments vary greatly in aim and complexity, ranging from purely descriptive work to complex, quantitative and even sub-resolution studies that require more detailed reporting and quality control measures.

To solve this problem, the 4D Nucleome Initiative (4DN) (1, 2) Imaging Standards Working Group (IWG), working in conjunction with the BioImaging North America (BINA) Quality Control and Data Management Working Group (QC-DM-WG) (3), here propose light Microscopy Metadata specifications that scale with experimental intent and with the complexity of the instrumentation and analytical requirements. They consist of a revision of the Core of the Open Microscopy Environment (OME) Data Model, which forms the basis for the widely adopted Bio-Formats library (4-6), accompanied by a suite of three extensions, each with three tiers, allowing the classification of imaging experiments into levels of increasing imaging and analytical complexity (7, 8). Hence these specifications not only provide an OME-based comprehensive set of metadata elements that should be recorded, but they also specify which subset of the full list should be recorded for a given experimental tier. In order to evaluate the extent of community interest, an extensive outreach effort was conducted to present the proposed metadata specifications to members of several core-facilities and international bioimaging initiatives including the European Light Microscopy Initiative (ELMI), Global BioImaging (GBI), and European Molecular Biology Laboratory (EMBL) - European Bioinformatics Institute (EBI). Consequently, close ties were established between our endeavour and the undertakings of the recently established QUAlity Assessment and REProducibility for Instruments and Images in Light Microscopy global community initiative (9). As a result this flexible 4DN-BINA-OME (NBO namespace) framework (7, 8) represents a turning point towards achieving community-driven Microscopy Metadata standards that will increase data fidelity, improve repeatability and reproducibility, ease future analysis and facilitate the verifiable comparison of different datasets, experimental setups, and assays, and it demonstrates the method for future extensions. Such universally accepted microscopy standards would serve a similar purpose as the Encode guidelines successfully adopted by the genomic community (10, 11). The intention of this proposal is therefore to encourage participation, critiques and contributions from the entire imaging community and all stakeholders, including research and imaging scientists, facility personnel, instrument manufacturers, software developers, standards organizations, scientific publishers, and funders.
]]></description>
<dc:creator>Hammer, M.</dc:creator>
<dc:creator>Huisman, M.</dc:creator>
<dc:creator>Rigano, A.</dc:creator>
<dc:creator>Boehm, U.</dc:creator>
<dc:creator>Chambers, J. J.</dc:creator>
<dc:creator>Gaudreault, N.</dc:creator>
<dc:creator>North, A. J.</dc:creator>
<dc:creator>Pimentel, J. A.</dc:creator>
<dc:creator>Sudar, D.</dc:creator>
<dc:creator>Bajcsy, P.</dc:creator>
<dc:creator>Brown, C. M.</dc:creator>
<dc:creator>Corbett, A. D.</dc:creator>
<dc:creator>Faklaris, O.</dc:creator>
<dc:creator>Lacoste, J.</dc:creator>
<dc:creator>Laude, A.</dc:creator>
<dc:creator>Nelson, G.</dc:creator>
<dc:creator>Nitschke, R.</dc:creator>
<dc:creator>Farzam, F.</dc:creator>
<dc:creator>Smith, C.</dc:creator>
<dc:creator>Grunwald, D.</dc:creator>
<dc:creator>Strambio-De-Castillia, C.</dc:creator>
<dc:date>2021-04-26</dc:date>
<dc:identifier>doi:10.1101/2021.04.25.441198</dc:identifier>
<dc:title><![CDATA[Towards community-driven metadata standards for light microscopy: tiered specifications extending the OME model]]></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/cgi/content/short/2021.05.31.446382v1?rss=1">
<title>
<![CDATA[
Micro-Meta App: an interactive software tool to facilitate the collection of microscopy metadata based on community-driven specifications 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.05.31.446382v1?rss=1"
</link>
<description><![CDATA[
For the information content of microscopy images to be appropriately interpreted, reproduced, and meet FAIR (Findable Accessible Interoperable and Reusable) principles, they should be accompanied by detailed descriptions of microscope hardware, image acquisition settings, image pixel and dimensional structure, and instrument performance. Nonetheless, the thorough documentation of imaging experiments is significantly impaired by the lack of community-sanctioned easy-to-use software tools to facilitate the extraction and collection of relevant microscopy metadata. Here we present Micro-Meta App, an intuitive open-source software designed to tackle these issues that was developed in the context of nascent global bioimaging community organizations, including BioImaging North America (BINA) and QUAlity Assessment and REProducibility in Light Microscopy (QUAREP-LiMi), whose goal is to improve reproducibility, data quality and sharing value for imaging experiments. The App provides a user-friendly interface for building comprehensive descriptions of the conditions utilized to produce individual microscopy datasets as specified by the recently proposed 4DN-BINA-OME tiered-system of Microscopy Metadata model. To achieve this goal the App provides a visual guide for a microscope-user to: 1) interactively build diagrammatic representations of hardware configurations of given microscopes that can be easily reused and shared with colleagues needing to document similar instruments. 2) Automatically extracts relevant metadata from image files and facilitates the collection of missing image acquisition settings and calibration metrics associated with a given experiment. 3) Output all collected Microscopy Metadata to interoperable files that can be used for documenting imaging experiments and shared with the community. In addition to significantly lowering the burden of quality assurance, the visual nature of Micro-Meta App makes it particularly suited for training users that have limited knowledge of the intricacies of light microscopy experiments. To ensure wide-adoption by microscope-users with different needs Micro-Meta App closely interoperates with MethodsJ2 and OMERO.mde, two complementary tools described in parallel manuscripts.
]]></description>
<dc:creator>Rigano, A.</dc:creator>
<dc:creator>Ehmsen, S.</dc:creator>
<dc:creator>Ozturk, S. U.</dc:creator>
<dc:creator>Ryan, J.</dc:creator>
<dc:creator>Balashov, A.</dc:creator>
<dc:creator>Hammer, M.</dc:creator>
<dc:creator>Kirli, K.</dc:creator>
<dc:creator>Bellve, K.</dc:creator>
<dc:creator>Boehm, U.</dc:creator>
<dc:creator>Brown, C. M.</dc:creator>
<dc:creator>Chambers, J. J.</dc:creator>
<dc:creator>Coleman, R. A.</dc:creator>
<dc:creator>Cosolo, A.</dc:creator>
<dc:creator>Faklaris, O.</dc:creator>
<dc:creator>Fogarty, K.</dc:creator>
<dc:creator>Guilbert, T.</dc:creator>
<dc:creator>Hamacher, A. B.</dc:creator>
<dc:creator>Itano, M. S.</dc:creator>
<dc:creator>Keeley, D. P.</dc:creator>
<dc:creator>Kunis, S.</dc:creator>
<dc:creator>Lacoste, J.</dc:creator>
<dc:creator>Laude, A.</dc:creator>
<dc:creator>Ma, W.</dc:creator>
<dc:creator>Marcello, M.</dc:creator>
<dc:creator>Montero-Llopis, P.</dc:creator>
<dc:creator>Nelson, G.</dc:creator>
<dc:creator>Nitschke, R.</dc:creator>
<dc:creator>Pimentel, J. A.</dc:creator>
<dc:creator>Weidtkamp-Peters, S.</dc:creator>
<dc:creator>Park, P. J.</dc:creator>
<dc:creator>Alver, B.</dc:creator>
<dc:creator>Grunwald, D.</dc:creator>
<dc:creator>Strambio-De-Castillia, C.</dc:creator>
<dc:date>2021-05-31</dc:date>
<dc:identifier>doi:10.1101/2021.05.31.446382</dc:identifier>
<dc:title><![CDATA[Micro-Meta App: an interactive software tool to facilitate the collection of microscopy metadata based on community-driven specifications]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-05-31</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2021.06.05.447195v1?rss=1">
<title>
<![CDATA[
Quantification of Antisense Oligonucleotides by Splint Ligation and Quantitative Polymerase Chain Reaction 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.06.05.447195v1?rss=1"
</link>
<description><![CDATA[
Reliable detection and quantification of antisense oligonucleotides (ASOs) in experimental and clinical specimens is essential to understand the biological function of novel oligonucleotide-based therapeutics. In this study, we describe a method to detect and quantify ASOs in biological samples, whereby the ASO acts as a splint to direct the ligation of complementary probes and quantitative real-time PCR was used to monitor ligation products. Low levels of 2'-O-MOE gapmer ASO in serum, liver, kidney, lung, heart, muscle, and brain tissues can be detected over a 6-log linear range for detection using this method. This method allows quantification of various types of chemically modified ASOs, including PS linkage, 2'-OMe, 2'-O-MOE, locked nucleic acid (LNA), and siRNA. This method does not require probe modifications, and can be performed using standard laboratory equipment; making it a fast, sensitive, and reliable technique that can be widely applied. This detection method may find potential applications in detection of therapeutic oligonucleotides in biological samples.
]]></description>
<dc:creator>Shin, M.</dc:creator>
<dc:creator>Krishnamurthy, P. M.</dc:creator>
<dc:creator>Watts, J. K.</dc:creator>
<dc:date>2021-06-05</dc:date>
<dc:identifier>doi:10.1101/2021.06.05.447195</dc:identifier>
<dc:title><![CDATA[Quantification of Antisense Oligonucleotides by Splint Ligation and Quantitative Polymerase Chain Reaction]]></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/cgi/content/short/2021.07.29.454218v1?rss=1">
<title>
<![CDATA[
A cohesin traffic pattern genetically linked to gene regulation 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.07.29.454218v1?rss=1"
</link>
<description><![CDATA[
Cohesin-mediated loop extrusion folds interphase chromosomes at the ten to hundreds kilobases scale. This process produces structural features such as loops and topologically associating domains. We identify three types of cis-elements that define the chromatin folding landscape generated by loop extrusion. First, CTCF sites form boundaries by stalling extruding cohesin, as shown before. Second, transcription termination sites form boundaries by acting as cohesin unloading sites. RNA polymerase II contributes to boundary formation at transcription termination sites. Third, transcription start sites form boundaries that are mostly independent of cohesin, but are sites where cohesin can pause. Together with cohesin loading at enhancers, and possibly other cis-elements, these loci create a dynamic pattern of cohesin traffic along the genome that guides enhancer-promoter interactions. Disturbing this traffic pattern, by removing CTCF barriers, renders cells sensitive to knock-out of genes involved in transcription initiation, such as the SAGA and TFIID complexes, and RNA processing such DEAD-Box RNA helicases. In the absence of CTCF, several of these factors fail to be efficiently recruited to active promoters. We propose that the complex pattern of cohesin movement along chromatin contributes to appropriate promoter-enhancer interactions and localization of transcription and RNA processing factors to active genes.

HIGHLIGHTSO_LIAt least three types of chromatin boundaries regulate a cohesin traffic pattern.
C_LIO_LIThe cohesin traffic pattern guides enhancer-promoter interactions.
C_LIO_LIRemoving CTCF renders cells sensitive to deletion of RNA processing and gene regulation genes.
C_LIO_LIDepleting CTCF affects localization of RNA processing and gene regulatory proteins.
C_LI
]]></description>
<dc:creator>Valton, A.-L.</dc:creator>
<dc:creator>Venev, S. V.</dc:creator>
<dc:creator>Mair, B.</dc:creator>
<dc:creator>Khokhar, E.</dc:creator>
<dc:creator>Tong, A. H.</dc:creator>
<dc:creator>Usaj, M.</dc:creator>
<dc:creator>Chan, K. S.</dc:creator>
<dc:creator>Pai, A.</dc:creator>
<dc:creator>Moffat, J.</dc:creator>
<dc:creator>Dekker, J.</dc:creator>
<dc:date>2021-07-30</dc:date>
<dc:identifier>doi:10.1101/2021.07.29.454218</dc:identifier>
<dc:title><![CDATA[A cohesin traffic pattern genetically linked to gene regulation]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2021-07-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2021.08.26.457801v1?rss=1">
<title>
<![CDATA[
Development of a flexible split prime editor using truncated reverse transcriptase 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.08.26.457801v1?rss=1"
</link>
<description><![CDATA[
Prime Editor (PE) has tremendous promise for gene therapy. However, it remains a challenge to deliver PE (>6.3 kb) in vivo. Although PE can be split into two fragments and delivered using dual adeno-associated viruses (AAVs), choice of split sites within Cas9 - which affects editing efficiency - is limited due to the large size of PE. Furthermore, the potential effect of overexpressing RT in mammalian cells is largely unknown. Here, we developed a compact PE with complete deletion of the RNase H domain of reverse transcriptase (RT), which showed comparable editing to full-length PE. Using compact PE, we tested the effect of 4 different Cas9 split sites and found that the Glu 573 split site supports robust editing (up to 93% of full-length PE). The compact PE, but not PE2, abolished its binding to eRF1 and showed minimal effect on stop codon readthrough, which therefore might reduce the effects on protein biosynthesis. This study identifies a safe and efficient compact PE2 that enables flexible split-PE design to facilitate efficient delivery in vivo and advance the utility of prime editing.
]]></description>
<dc:creator>Xue, W.</dc:creator>
<dc:creator>Zheng, C.</dc:creator>
<dc:creator>LIANG, S.</dc:creator>
<dc:creator>Liu, P.</dc:creator>
<dc:creator>Liu, B.</dc:creator>
<dc:creator>Kwan, S.</dc:creator>
<dc:creator>Wolfe, S.</dc:creator>
<dc:date>2021-08-27</dc:date>
<dc:identifier>doi:10.1101/2021.08.26.457801</dc:identifier>
<dc:title><![CDATA[Development of a flexible split prime editor using truncated reverse transcriptase]]></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/cgi/content/short/2020.11.07.372151v1?rss=1">
<title>
<![CDATA[
Orthogonal CRISPR-Cas genome editing and efficient inhibition with anti-CRISPRs in zebrafish embryos 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2020.11.07.372151v1?rss=1"
</link>
<description><![CDATA[
The CRISPR-Cas universe continues to expand. The type II CRISPR-Cas system from Streptococcus pyogenes (SpyCas9) is the most widely used for genome editing due to its high efficiency in cells and organisms. However, concentrating on a single CRISPR-Cas system imposes limits on target selection and multiplexed genome engineering. We hypothesized that CRISPR-Cas systems originating from different bacterial species could operate simultaneously and independently due to their distinct single-guide RNAs (sgRNAs) or CRISPR-RNAs (crRNAs), and protospacer adjacent motifs (PAMs). Additionally, we hypothesized that CRISPR-Cas activity in zebrafish could be regulated through the expression of inhibitory anti-CRISPR (Acr) proteins. Here, we use a simple mutagenesis approach to demonstrate that CRISPR-Cas systems from Streptococcus pyogenes (SpyCas9), Streptococcus aureus (SauCas9), Lachnospiraceae bacterium (LbaCas12a, previously known as LbCpf1), are orthogonal systems capable of operating simultaneously in zebrafish. CRISPR systems from Acidaminococcus sp. (AspCas12a, previously known as AsCpf1) and Neisseria meningitidis (Nme2Cas9) were also active in embryos. We implemented multichannel CRISPR recording using three CRISPR systems and show that LbaCas12a may provide superior information density compared to previous methods. We also demonstrate that type II Acrs (anti-CRISPRs) are effective inhibitors of SpyCas9 in zebrafish. Our results indicate that at least five CRISPR-Cas systems and two anti-CRISPR proteins are functional in zebrafish embryos. These orthogonal CRISPR-Cas systems and Acr proteins will enable combinatorial and intersectional strategies for spatiotemporal control of genome editing and genetic recording in animals.
]]></description>
<dc:creator>Takasugi, P. R.</dc:creator>
<dc:creator>Drage, E. P.</dc:creator>
<dc:creator>Kanishka, S. N.</dc:creator>
<dc:creator>Higbee, M. A.</dc:creator>
<dc:creator>Gagnon, J. A.</dc:creator>
<dc:date>2020-11-08</dc:date>
<dc:identifier>doi:10.1101/2020.11.07.372151</dc:identifier>
<dc:title><![CDATA[Orthogonal CRISPR-Cas genome editing and efficient inhibition with anti-CRISPRs in zebrafish embryos]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2020-11-08</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2021.03.09.434681v1?rss=1">
<title>
<![CDATA[
RNA-silencing induces target gene relocalization toward a specialized nuage domain 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2021.03.09.434681v1?rss=1"
</link>
<description><![CDATA[
The authors wish to withdraw this manuscript and apologize for errors in the initial submission. All the original experiments were performed by YY. Unfortunately, JP and members of the Mello lab have not been able to replicate some aspects of the study. JP has failed to independently reproduce the specific results showing RNAi-triggered relocalization of target RNA, and P granule specific accumulation of (the P granule component GLH-1) as reported. The conditions/strains analyzed by JP were as follows: (1) oma-1 FISH on WT worms [control, 6 hr and 12 hr oma-1(RNAi)]. (2) oma-1 FISH on OMA-1:GFP worms [control, 6 hr oma-1(RNAi), or 6 hr gfp(RNAi)]. (3) oma-1 FISH on WT worms [control, 4hr, 6hr, 8 hr, and 10 hr oma-1(RNAi)]. 10-23 gonads were analyzed per experiment. Fixation conditions were essentially as described, with the only known difference being that gonads were not exposed to detergent prior to fixation. Using YYs reagents and protocol the Mello lab has not observed an obvious relocalization of target RNA to P granules (marked by GFP::GLH-1) after 6 hrs oma-1(RNAi); n=92 gonads. CM, JP and DG consider that the published images accurately represent the image stacks provided by YY as representative, raw data, but JP and CM note configurations of FISH signals in germ nuclei and gonad anatomy that they consider unusual. CM, JP and DG have not detected any evidence of image manipulation.

YY states that none of the raw image data were manipulated beyond standard adjustments for brightness and contrast prior to processing images for publication as described. However, YY reports that the images were not representative of the majority of sample gonads, and instead were pre-selected under low magnification for rare examples with asymmetrical, expanded P granules.

Efforts to identify conditions that explain the rare gonads imaged by YY continue in the Mello lab, as do efforts to reproduce independently each of the other reported results; we plan to provide an update in the near future.
]]></description>
<dc:creator>Mello, C.</dc:creator>
<dc:creator>Yang, Y.</dc:creator>
<dc:creator>Grunwald, D.</dc:creator>
<dc:creator>Priess, J.</dc:creator>
<dc:date>2021-03-11</dc:date>
<dc:identifier>doi:10.1101/2021.03.09.434681</dc:identifier>
<dc:title><![CDATA[RNA-silencing induces target gene relocalization toward a specialized nuage domain]]></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/cgi/content/short/2022.01.03.474854v1?rss=1">
<title>
<![CDATA[
High-throughput analysis of ANRIL circRNA isoforms in human pancreatic islets 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.01.03.474854v1?rss=1"
</link>
<description><![CDATA[
The antisense non-coding RNA in the INK locus (ANRIL) is a hotspot for genetic variants associated with cardiometabolic disease. We recently found increased ANRIL abundance in human pancreatic islets from donors with certain Type II Diabetes (T2D) risk-SNPs, including a T2D risk-SNP located within ANRIL exon 2 associated with beta cell proliferation. Recent studies have found that expression of circular species of ANRIL is linked to the regulation of cardiovascular phenotypes. Less is known about how the abundance of circular ANRIL may influence T2D phenotypes. Herein, we sequence circular RNA in pancreatic islets to characterize circular isoforms of ANRIL. We identify highly expressed circular ANRIL isoforms whose expression is correlated across dozens of individuals and characterize ANRIL splice sites that are commonly involved in back-splicing. We find that samples with the T2D risk allele in ANRIL exon 2 had higher ratios of circular to linear ANRIL compared to protective-allele carriers, and that higher circular:linear ANRIL was associated with decreased beta cell proliferation. Our study points to a combined involvement of both linear and circular ANRIL species in T2D phenotypes and opens the door for future studies of the molecular mechanisms by which ANRIL impacts cellular function in pancreatic islets.
]]></description>
<dc:creator>MacMillan, H. J.</dc:creator>
<dc:creator>Kong, Y.</dc:creator>
<dc:creator>Calvo-Roitberg, E.</dc:creator>
<dc:creator>Alonso, L. C.</dc:creator>
<dc:creator>Pai, A. A.</dc:creator>
<dc:date>2022-01-04</dc:date>
<dc:identifier>doi:10.1101/2022.01.03.474854</dc:identifier>
<dc:title><![CDATA[High-throughput analysis of ANRIL circRNA isoforms in human pancreatic islets]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-01-04</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2022.01.18.476504v1?rss=1">
<title>
<![CDATA[
A family of C. elegans VASA homologs control Argonaute pathway specificity and promote transgenerational silencing 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.01.18.476504v1?rss=1"
</link>
<description><![CDATA[
Germline Argonautes direct transcriptome surveillance within peri-nuclear membraneless organelles called nuage. In C. elegans, a family of Vasa-related Germ Line Helicase (GLH) proteins localize in, and promote the formation of nuage called P granules. Previous studies have implicated GLH proteins in inherited silencing but direct roles in amplification of small RNAs, or in target mRNA or Argonatue binding have not been identified. Here we show that GLH proteins compete with each other to control Argonaute pathway specificity, bind directly to Argonaute-target mRNAs and act to promote the amplification of small RNAs required for transgenerational inheritance. We show that the ATPase cycle of GLH-1 regulates its direct binding to the Argonaute WAGO-1 which engages amplified small RNAs. Our findings support a dynamic and direct role for GLH proteins in inherited silencing beyond their role as structural components of nuage.
]]></description>
<dc:creator>Dai, S.</dc:creator>
<dc:creator>Tang, X.</dc:creator>
<dc:creator>Li, L.</dc:creator>
<dc:creator>Ishidate, T.</dc:creator>
<dc:creator>Ozturk, A. R.</dc:creator>
<dc:creator>Chen, H.</dc:creator>
<dc:creator>Yan, Y.-H.</dc:creator>
<dc:creator>Dong, M.-Q.</dc:creator>
<dc:creator>Shen, E.-Z.</dc:creator>
<dc:creator>Mello, C. C.</dc:creator>
<dc:date>2022-01-18</dc:date>
<dc:identifier>doi:10.1101/2022.01.18.476504</dc:identifier>
<dc:title><![CDATA[A family of C. elegans VASA homologs control Argonaute pathway specificity and promote transgenerational silencing]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-01-18</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2022.04.10.487797v1?rss=1">
<title>
<![CDATA[
In situ single particle classification reveals distinct 60S maturation intermediates in cells 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.04.10.487797v1?rss=1"
</link>
<description><![CDATA[
Electron cryo-microscopy (cryo-EM) can generate high-resolution views of cells with faithful preservation of molecular structure. In situ cryo-EM, therefore, has enormous potential to reveal the atomic details of biological processes in their native context. However, in practice, the utility of in situ cryo-EM is limited by the difficulty of reliably locating and confidently identifying molecular targets (particles) and their conformational states in the crowded cellular environment. We recently showed that 2DTM, a fine-grained template-based search applied to cryo-EM micrographs, can localize particles in two-dimensional views of cells with high precision. Here we demonstrate that the signal-to-noise ratio (SNR) observed with 2DTM can be used to differentiate related complexes in focused ion beam (FIB)-milled cell sections. We apply this method in two contexts to locate and classify related intermediate states of 60S ribosome biogenesis in the Saccharomyces cerevisiae cell nucleus. In the first, we separate the nuclear pre-60S population from the cytoplasmic mature 60S population, using the subcellular localization to validate assignment. In the second, we show that relative 2DTM SNRs can be used to separate mixed populations of nuclear pre-60S that are not visually separable. We use a maximum likelihood approach to define the probability of each particle belonging to each class, thereby establishing a statistic to describe the confidence of our classification. Without the need to generate 3D reconstructions, 2DTM can be applied even when only a few target particles exist in a cell.
]]></description>
<dc:creator>Lucas, B. A.</dc:creator>
<dc:creator>Zhang, K.</dc:creator>
<dc:creator>Loerch, S.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:date>2022-04-10</dc:date>
<dc:identifier>doi:10.1101/2022.04.10.487797</dc:identifier>
<dc:title><![CDATA[In situ single particle classification reveals distinct 60S maturation intermediates in cells]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2022.04.19.488762v1?rss=1">
<title>
<![CDATA[
Structural Basis of MicroRNA Biogenesis by Dicer-1 and Its Partner Protein Loqs-PB 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.04.19.488762v1?rss=1"
</link>
<description><![CDATA[
In animals and plants, Dicer enzymes collaborate with double-stranded RNA-binding proteins to convert precursor-microRNAs (pre-miRNAs) into miRNA duplexes. We report six cryo-EM structures of Drosophila Dicer-1 and its partner Loqs-PB. The structures show Dicer-1*Loqs-PB (1) before binding pre-miRNA, (2) after binding and in a catalytically competent state, (3) after nicking one arm of the pre-miRNA, (4) following complete dicing and initial product release. Our reconstructions suggest that pre-miRNA binds a rare, open conformation of the Dicer-1*Loqs-PB heterodimer, enabling conformational proofreading. The Dicer-1 dsRBD and three Loqs-PB dsRBD domains form a tight belt around the pre-miRNA, distorting the RNA helix to place the scissile phosphodiester bonds in the RNase III active sites. Pre-mRNA cleavage shifts the RNA- binding domains and tightens Dicer-1, promoting product release. Our data suggest a model for how the Dicer-1*Loqs-PB complex effects a complete cycle of pre-miRNA recognition, stepwise endonuclease cleavage, and sequential product release.
]]></description>
<dc:creator>Jourevleva, K.</dc:creator>
<dc:creator>Golovenko, D.</dc:creator>
<dc:creator>Demo, G.</dc:creator>
<dc:creator>Dutcher, R. C.</dc:creator>
<dc:creator>Hall, T. M.</dc:creator>
<dc:creator>Zamore, P. D.</dc:creator>
<dc:creator>Korostelev, A. A.</dc:creator>
<dc:date>2022-04-20</dc:date>
<dc:identifier>doi:10.1101/2022.04.19.488762</dc:identifier>
<dc:title><![CDATA[Structural Basis of MicroRNA Biogenesis by Dicer-1 and Its Partner Protein Loqs-PB]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-04-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2022.06.13.495969v1?rss=1">
<title>
<![CDATA[
Defocus Corrected Large Area Cryo-EM (DeCo-LACE) for Label-Free Detection of Molecules across Entire Cell Sections 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.06.13.495969v1?rss=1"
</link>
<description><![CDATA[
A major goal of biological imaging is localization of biomolecules inside a cell. Fluorescence microscopy can lo-calize biomolecules inside whole cells and tissues, but its ability to count biomolecules and accuracy of the spatial coordinates is limited by the wavelength of visible light. Cryo-electron microscopy (cryo-EM) provides highly accurate position and orientation information of biomolecules but is often confined to small fields of view inside a cell, limiting biological context. In this study we use a new data-acquisition scheme called "Defocus-Corrected Large-Area cryo-EM" (DeCo-LACE) to collect high-resolution images of entire sections (100 - 200 nm thick lamel-lae) of neutrophil-like mouse cells, representing 1-2% of the total cellular volume. We use 2D template matching (2DTM) to determine localization and orientation of the large ribosomal subunit in these sections. These data provide "maps" of ribosomes across entire sections of mammalian cells. This high-throughput cryo-EM data collection approach together with 2DTM will advance visual proteomics and provide biological insight that cannot be obtained by other methods.
]]></description>
<dc:creator>Elferich, J.</dc:creator>
<dc:creator>Schiroli, G.</dc:creator>
<dc:creator>Scadden, D.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:date>2022-06-14</dc:date>
<dc:identifier>doi:10.1101/2022.06.13.495969</dc:identifier>
<dc:title><![CDATA[Defocus Corrected Large Area Cryo-EM (DeCo-LACE) for Label-Free Detection of Molecules across Entire Cell Sections]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-06-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2022.06.29.498088v1?rss=1">
<title>
<![CDATA[
Chemical engineering of therapeutic siRNAs for allele-specific gene silencing in vivo in CNS 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.06.29.498088v1?rss=1"
</link>
<description><![CDATA[
Small interfering RNAs (siRNAs) are a new class of drugs, exhibiting sequence-driven, potent, and sustained silencing of gene expression in vivo. We recently demonstrated that siRNA chemical architectures can be optimized to provide efficient delivery to the CNS. Many genetically-defined neurodegenerative disorders are autosomal dominant favoring selective silencing of the mutant allele. In some cases, successful targeting of the mutant allele requires targeting of a single nucleotide polymorphism (SNP) heterozygosity. Using Huntingtons disease as a model, we demonstrate allele-specific RNAi-based silencing of gene expression in vivo and in neurons differentiated from HD patient-derived iPSCs. A series of in vitro screens, with chemical and thermodynamic optimization, identified compounds with >50-fold selectivity for the mutant HD-causing allele, based on a single nucleotide difference. The optimized compound exhibits selective silencing of mutant huntingtin (HTT) protein in patient derived cells and throughout the HD mouse brain, providing a demonstration of SNP-based allele-specific RNAi silencing of gene expression in vivo in the CNS. The ability to target a disease-causing allele using RNAi-based therapies could be applied to a wide range of dominant CNS disorders, where maintenance of wild-type expression is essential.
]]></description>
<dc:creator>Conroy, F.</dc:creator>
<dc:creator>Miller, R.</dc:creator>
<dc:creator>Alterman, J. F.</dc:creator>
<dc:creator>Hassler, M. R.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Godinho, B. M. D. C.</dc:creator>
<dc:creator>Knox, E. G.</dc:creator>
<dc:creator>Sapp, E.</dc:creator>
<dc:creator>Sousa, J.</dc:creator>
<dc:creator>Yamada, K.</dc:creator>
<dc:creator>Mahmood, F.</dc:creator>
<dc:creator>Boudi, A.</dc:creator>
<dc:creator>Kegel-Gleason, K.</dc:creator>
<dc:creator>DiFiglia, M.</dc:creator>
<dc:creator>Aronin, N.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Pfister, E. L.</dc:creator>
<dc:date>2022-07-02</dc:date>
<dc:identifier>doi:10.1101/2022.06.29.498088</dc:identifier>
<dc:title><![CDATA[Chemical engineering of therapeutic siRNAs for allele-specific gene silencing in vivo in CNS]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2022.06.28.498012v1?rss=1">
<title>
<![CDATA[
Silencing of ApoE with Divalent siRNAs Drives Activation of Immune Clearance Pathways and Improves Amyloid Pathology in Mouse Models of Alzheimer's Disease 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.06.28.498012v1?rss=1"
</link>
<description><![CDATA[
The most common genetic risk factor for late-onset Alzheimers disease (AD) is the APOE4 allele, with evidence for gain- and loss-of-function mechanisms. ApoE knockout in mice abrogates AD phenotypes but causes severe atherosclerosis due to the role of liver ApoE in cholesterol homeostasis. Previous attempts to inhibit brain-specific ApoE with anti-sense oligonucleotides only modestly reduced ApoE expression and had no effect on amyloid burden in adult AD mice. Here, we optimized a divalent small interfering RNA (di-siRNA) to selectively and potently silence ApoE in the brain. Silencing brain ApoE in AD mice significantly reduced amyloid plaque formation without affecting systemic cholesterol levels, confirming that brain and liver APOE pools are spatially and functionally distinct. Mechanistically, APOE appears to be a scaffold for beta-amyloid aggregation that limits clearance by microglia. Di-siRNAs from this study can be taken to pre-clinical and clinical trials to accelerate development of AD-modifying therapies and establish siRNA-based modulation of ApoE as a viable path towards therapeutic development.
]]></description>
<dc:creator>Ferguson, C.</dc:creator>
<dc:creator>Hildebrand, S.</dc:creator>
<dc:creator>Godinho, B. M. D. C.</dc:creator>
<dc:creator>Buchwald, J.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Coles, A.</dc:creator>
<dc:creator>Grigorenko, A.</dc:creator>
<dc:creator>Vanjielli, L.</dc:creator>
<dc:creator>Sousa, J.</dc:creator>
<dc:creator>McHugh, N.</dc:creator>
<dc:creator>Hassler, M.</dc:creator>
<dc:creator>Santarelli, F.</dc:creator>
<dc:creator>Heneka, M. T.</dc:creator>
<dc:creator>Rogaev, E.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:date>2022-07-02</dc:date>
<dc:identifier>doi:10.1101/2022.06.28.498012</dc:identifier>
<dc:title><![CDATA[Silencing of ApoE with Divalent siRNAs Drives Activation of Immune Clearance Pathways and Improves Amyloid Pathology in Mouse Models of Alzheimer's Disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-02</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2022.07.08.499317v1?rss=1">
<title>
<![CDATA[
Asymmetric trichotomous data partitioning enables development of predictive machine learning models using limited siRNA efficacy datasets 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.07.08.499317v1?rss=1"
</link>
<description><![CDATA[
Chemically modified small interfering RNAs (siRNAs) are promising therapeutics guiding sequence-specific silencing of disease genes. However, identifying chemically modified siRNA sequences that effectively silence target genes is a challenge. Such determinations necessitate computational algorithms. Machine Learning (ML) is a powerful predictive approach for tackling biological problems, but typically requires datasets significantly larger than most available siRNA datasets. Here, we describe a framework for applying ML to a small dataset (356 modified sequences) for siRNA efficacy prediction. To overcome noise and biological limitations in siRNA datasets, we apply a trichotomous (using two thresholds) partitioning approach, producing several combinations of classification threshold pairs. We then test the effects of different thresholds on random forest (RF) ML model performance using a novel evaluation metric accounting for class imbalances. We identify thresholds yielding a model with high predictive power outperforming a simple linear classification model generated from the same data. Using a novel method to extract model features, we observe target site base preferences consistent with current understanding of the siRNA-mediated silencing mechanism, with RF providing higher resolution than the linear model. This framework applies to any classification challenge involving small biological datasets, providing an opportunity to develop high-performing design algorithms for oligonucleotide therapies.
]]></description>
<dc:creator>Monopoli, K. R.</dc:creator>
<dc:creator>Korkin, D.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:date>2022-07-10</dc:date>
<dc:identifier>doi:10.1101/2022.07.08.499317</dc:identifier>
<dc:title><![CDATA[Asymmetric trichotomous data partitioning enables development of predictive machine learning models using limited siRNA efficacy datasets]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-07-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2022.08.04.502788v1?rss=1">
<title>
<![CDATA[
Relaxed targeting rules allow PIWI-clade Argonaute proteins to silence ever-mutating transposons 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.08.04.502788v1?rss=1"
</link>
<description><![CDATA[
In animals, piRNAs direct PIWI-clade Argonaute proteins to slice complementary transposon transcripts. Transposons can evade silencing through target site mutations. We report that PIWIs efficiently cleave transcripts only partially paired to their piRNA guide. Measurements of mouse PIWI protein affinity and cleavage rates for thousands of RNAs in vitro and in vivo show that PIWI slicing tolerates mismatches to any target nucleotide, including those flanking the scissile phosphate. Although piRNA 5 terminal nucleotides accelerate target finding, they are dispensable for binding or catalysis--unlike AGO-clade Argonautes, which require uninterrupted siRNA:target pairing from the seed to the nucleotides past the scissile bond. PIWIs are thus better equipped than AGOs to target newly acquired or rapidly diverging endogenous transposons without recourse to novel small RNA guides.
]]></description>
<dc:creator>Gainetdinov, I.</dc:creator>
<dc:creator>Cecchini, K.</dc:creator>
<dc:creator>Vega-Badillo, J.</dc:creator>
<dc:creator>Bagci, A.</dc:creator>
<dc:creator>Colpan, C.</dc:creator>
<dc:creator>Arif, A.</dc:creator>
<dc:creator>Wu, P.-H.</dc:creator>
<dc:creator>Zamore, P. D.</dc:creator>
<dc:date>2022-08-05</dc:date>
<dc:identifier>doi:10.1101/2022.08.04.502788</dc:identifier>
<dc:title><![CDATA[Relaxed targeting rules allow PIWI-clade Argonaute proteins to silence ever-mutating transposons]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-08-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2022.08.15.504001v1?rss=1">
<title>
<![CDATA[
Structure of the catalytically active APOBEC3G bound to a DNA oligonucleotide inhibitor reveals tetrahedral geometry of the transition state 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.08.15.504001v1?rss=1"
</link>
<description><![CDATA[
APOBEC3 proteins (A3s) are enzymes that catalyze deamination of cytidine to uridine in single-stranded DNA (ssDNA) substrates, thus playing a key role in innate antiviral immunity. However, APOBEC3 family has also been linked to many mutational signatures in cancer cells, which has led to intense interest to develop inhibitors of A3s catalytic activity as therapeutics as well as tools to study A3s biochemistry, structure and cellular function. Recent studies have shown that ssDNA containing 2'-deoxy-zebularine (dZ-ssDNA) is an inhibitor of A3s such as A3A, A3B and A3G, although atomic determinants of this activity remained unknown. To fill this knowledge gap, we determined a 1.5 [A] resolution structure of a dZ-ssDNA inhibitor bound to active A3G. The crystal structure revealed that the activated dZ/H2O mimics the transition state by coordinating the active site Zn2+ and engaging in additional stabilizing interactions, such as the one with the catalytic residues E259. Therefore, this structure allowed us to capture the first snapshot of the A3s transition state, and suggests that developing transition-state mimicking inhibitors may provide a new opportunity to design more targeted molecules for A3s in the future.
]]></description>
<dc:creator>Maiti, A.</dc:creator>
<dc:creator>Hedger, A.</dc:creator>
<dc:creator>Myint, W.</dc:creator>
<dc:creator>Balachandran, V.</dc:creator>
<dc:creator>Watts, J.</dc:creator>
<dc:creator>Schiffer, C. A.</dc:creator>
<dc:creator>Matsuo, H.</dc:creator>
<dc:date>2022-08-15</dc:date>
<dc:identifier>doi:10.1101/2022.08.15.504001</dc:identifier>
<dc:title><![CDATA[Structure of the catalytically active APOBEC3G bound to a DNA oligonucleotide inhibitor reveals tetrahedral geometry of the transition state]]></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/cgi/content/short/2022.09.06.506795v1?rss=1">
<title>
<![CDATA[
Di-valent siRNA Mediated Silencing of MSH3 Blocks Somatic Repeat Expansion in Mouse Models of Huntington's Disease 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.09.06.506795v1?rss=1"
</link>
<description><![CDATA[
Huntingtons Disease (HD) is a severe neurodegenerative disorder caused by expansion of the CAG trinucleotide repeat tract in the huntingtin gene. Inheritance of expanded CAG repeats is needed for HD manifestation, but further somatic expansion of the repeat tract in non-dividing cells, particularly striatal neurons, hastens disease onset. Called somatic repeat expansion, this process is mediated by the mismatch repair (MMR) pathway. Among MMR components identified as modifiers of HD onset, MutS Homolog 3 (MSH3) has emerged as a potentially safe and effective target for therapeutic intervention. Here, we identify fully chemically modified short interfering RNA (siRNA) that robustly silence MSH3 in vitro and in vivo. When synthesized in a di-valent scaffold, siRNA-mediated silencing of MSH3 effectively blocked CAG repeat expansion in striatum of two HD mouse models without impacting tumor-associated microsatellite instability. Our findings establish a novel paradigm for treating patients with HD and other repeat expansion diseases.

One Sentence SummarySilencing MSH3 in the CNS of two models of Huntingtons disease using di-valent siRNA blocks disease-accelerating somatic expansion of CAG repeats.
]]></description>
<dc:creator>O'Reilly, D.</dc:creator>
<dc:creator>Belgrad, J.</dc:creator>
<dc:creator>Ferguson, C.</dc:creator>
<dc:creator>Summers, A.</dc:creator>
<dc:creator>Sapp, E.</dc:creator>
<dc:creator>McHugh, C.</dc:creator>
<dc:creator>Mathews, E.</dc:creator>
<dc:creator>Buchwald, J.</dc:creator>
<dc:creator>Ly, S.</dc:creator>
<dc:creator>Echeverria Moreno, D.</dc:creator>
<dc:creator>Kennedy, Z.</dc:creator>
<dc:creator>Hariharan, V.</dc:creator>
<dc:creator>Monopoli, K.</dc:creator>
<dc:creator>Yang, X.</dc:creator>
<dc:creator>Carroll, J.</dc:creator>
<dc:creator>Difiglia, M.</dc:creator>
<dc:creator>Aronin, N.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:date>2022-09-06</dc:date>
<dc:identifier>doi:10.1101/2022.09.06.506795</dc:identifier>
<dc:title><![CDATA[Di-valent siRNA Mediated Silencing of MSH3 Blocks Somatic Repeat Expansion in Mouse Models of Huntington's Disease]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-09-06</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/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/cgi/content/short/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/cgi/content/short/2022.10.04.510877v1?rss=1">
<title>
<![CDATA[
The nuclear Argonaute HRDE-1 directs target gene re-localization and shuttles to nuage to promote small RNA mediated inherited silencing 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.10.04.510877v1?rss=1"
</link>
<description><![CDATA[
Argonaute small-RNA pathways engage heterochromatin-silencing co-factors to promote transgenerational inheritance in animals. However, little is known about how heterochromatin and small-RNA pathways interact to transmit silencing. Here we show that the induction of heterochromatin silencing in C. elegans by RNAi or by artificially tethering pathway components to target RNA correlates with the co-localization of the target alleles in pachytene nuclei. Tethering the nuclear Argonaute WAGO-9/HRDE-1 induces heterochromatin formation, but also functions independently to induce small-RNA amplification. We show that HRDE-1 shuttles to nuage domains called mutator foci where amplification is thought to occur. Tethering a heterochromatin-silencing factor, NRDE-2, induces heterochromatin silencing and also induces the de-novo synthesis of HRDE-1 guide RNAs, and through HRDE-1 acts to further amplify downstream small-RNA silencing. Our findings support a model in which HRDE-1 functions both upstream, to initiate heterochromatin silencing, and downstream, to stimulate small-RNA amplification, establishing a self-enforcing mechanism that propagates silencing to offspring.
]]></description>
<dc:creator>Ding, Y.-H.</dc:creator>
<dc:creator>Ochoa, H.</dc:creator>
<dc:creator>Ishidate, T.</dc:creator>
<dc:creator>Mello, C.</dc:creator>
<dc:date>2022-10-05</dc:date>
<dc:identifier>doi:10.1101/2022.10.04.510877</dc:identifier>
<dc:title><![CDATA[The nuclear Argonaute HRDE-1 directs target gene re-localization and shuttles to nuage to promote small RNA mediated inherited silencing]]></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/cgi/content/short/2022.10.21.512368v1?rss=1">
<title>
<![CDATA[
Career Self-Efficacy Disparities in Underrepresented Biomedical Scientist Trainees 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.10.21.512368v1?rss=1"
</link>
<description><![CDATA[
The present study examines racial, ethnic, and gender disparities in career self-efficacy amongst 6077 US citizens and US naturalized graduate and postdoctoral trainees. Respondents from biomedical fields completed surveys administered by the National Institutes of Health Broadening Experiences in Scientific Training (NIH BEST) programs across 17 US institutional sites. Graduate and postdoctoral demographic and survey response data were examined to evaluate the impact of intersectional identities on trainee career self-efficacy. The study hypothesized that race, ethnicity and gender, and the relations between these identities, would impact trainee career self-efficacy. The analysis demonstrated that racial and ethnic group, gender, specific career interests (academic principal investigator vs. other careers), and seniority (junior vs. senior trainee level) were, to various degrees, all associated with trainee career self-efficacy and the effects were consistent across graduate and postdoctoral respondents. Implications for differing levels of self-efficacy are discussed, including factors and events during training that may contribute to (or undermine) career self-efficacy. The importance of mentorship for building research and career self-efficacy of trainees is discussed, especially with respect to those identifying as women and belonging to racial/ethnic populations underrepresented in biomedical sciences. The results underscore the need for change in the biomedical academic research community in order to retain a diverse biomedical workforce.
]]></description>
<dc:creator>Chatterjee, D.</dc:creator>
<dc:creator>Jacob, G. A.</dc:creator>
<dc:creator>Sturzenegger Varvayanis, S.</dc:creator>
<dc:creator>Wefes, I.</dc:creator>
<dc:creator>Chalkley, R.</dc:creator>
<dc:creator>Nogueira, A. T.</dc:creator>
<dc:creator>Fuhrmann, C.</dc:creator>
<dc:creator>Varadarajan, J.</dc:creator>
<dc:creator>Hubbard, N. M.</dc:creator>
<dc:creator>Gaines, C. H.</dc:creator>
<dc:creator>Layton, R. L.</dc:creator>
<dc:creator>Chaudhary, S.</dc:creator>
<dc:date>2022-10-21</dc:date>
<dc:identifier>doi:10.1101/2022.10.21.512368</dc:identifier>
<dc:title><![CDATA[Career Self-Efficacy Disparities in Underrepresented Biomedical Scientist Trainees]]></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/cgi/content/short/2022.11.16.516815v1?rss=1">
<title>
<![CDATA[
Formamide significantly enhances the efficiency of chemical adenylation of RNA sequencing ligation adaptors 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.11.16.516815v1?rss=1"
</link>
<description><![CDATA[
Pre-adenylated single-stranded DNA ligation adaptors are essential reagents in many next generation RNA sequencing library preparation protocols. These oligonucleotides can be adenylated enzymatically or chemically. Enzymatic adenylation reactions have high yield but are not amendable to scale up. In chemical adenylation, Adenosine 5{square}-phosphorimidazolide (ImpA) reacts with 5' phosphorylated DNA. It is easily scalable but gives poor yields, requiring labor-intensive cleanup steps. Here, we describe an improved chemical adenylation method using 95% formamide as the solvent, which results in the adenylation of oligonucleotides with >90% yield. In standard conditions, with water as the solvent, hydrolysis of the starting material to adenosine monophosphate limits the yields. To our surprise, we find that rather than increasing adenylation yields by decreasing the rate of ImpA hydrolysis, formamide does so by increasing the reaction rate between ImpA and 5'-phosphorylated DNA by [~]10 fold. The method described here enables straightforward preparation of chemically adenylated adapters with higher than 90% yield, simplifying reagent preparation for NGS.
]]></description>
<dc:creator>Hildebrand, S.</dc:creator>
<dc:creator>Hedger, A. K.</dc:creator>
<dc:creator>Watts, J.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:date>2022-11-16</dc:date>
<dc:identifier>doi:10.1101/2022.11.16.516815</dc:identifier>
<dc:title><![CDATA[Formamide significantly enhances the efficiency of chemical adenylation of RNA sequencing ligation adaptors]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-16</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2022.11.28.518275v1?rss=1">
<title>
<![CDATA[
From primordial clocks to circadian oscillators 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.11.28.518275v1?rss=1"
</link>
<description><![CDATA[
Circadian rhythms play an essential role in many biological processes and surprisingly only three prokaryotic proteins are required to constitute a true post-translational circadian oscillator. The evolutionary history of the three Kai proteins indicates that KaiC is the oldest member and central component of the clock, with subsequent additions of KaiB and KaiA to regulate its phosphorylation state for time synchronization. The canonical KaiABC system in cyanobacteria is well understood, but little is known about more ancient systems that possess just KaiBC, except for reports that they might exhibit a basic, hourglass-like timekeeping mechanism. Here, we investigate the primordial circadian clock in Rhodobacter sphaeroides (RS) that contains only KaiBC to elucidate its inner workings despite the missing KaiA. Using a combination X-ray crystallography and cryo-EM we find a novel dodecameric fold for KaiCRS where two hexamers are held together by a coiled-coil bundle of 12 helices. This interaction is formed by the C-terminal extension of KaiCRS and serves as an ancient regulatory moiety later superseded by KaiA. A coiled-coil register shift between daytime- and nighttime-conformations is connected to the phosphorylation sites through a long-range allosteric network that spans over 160 [A]. Our kinetic data identify the difference in ATP-to-ADP ratio between day and night as the environmental cue that drives the clock and further unravels mechanistic details that shed light on the evolution of self-sustained oscillators.
]]></description>
<dc:creator>Pitsawong, W.</dc:creator>
<dc:creator>Padua, R. A.</dc:creator>
<dc:creator>Grant, T.</dc:creator>
<dc:creator>Hoemberger, M.</dc:creator>
<dc:creator>Otten, R.</dc:creator>
<dc:creator>Bradshaw, N.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:creator>Kern, D.</dc:creator>
<dc:date>2022-11-29</dc:date>
<dc:identifier>doi:10.1101/2022.11.28.518275</dc:identifier>
<dc:title><![CDATA[From primordial clocks to circadian oscillators]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-11-29</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2023.02.01.526705v1?rss=1">
<title>
<![CDATA[
Quantification of gallium cryo-FIB milling damage in biological lamella 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.02.01.526705v1?rss=1"
</link>
<description><![CDATA[
Cryogenic electron microscopy (cryo-EM) has the potential to reveal the molecular details of biological processes in their native, cellular environment at atomic resolution. However, few cells are sufficiently thin to permit imaging with cryo-EM. Thinning of frozen cells to <500 nm lamellae by cryogenic focused ion beam (FIB) milling has enabled visualization of cellular structures with cryo-EM. FIB-milling represents a significant advance over prior approaches because of its ease of use, scalability, and lack of large-scale sample distortions. However, the amount of damage caused by FIB-milling to the generated thin cell section has not yet been determined. We recently described a new approach for detecting and identifying single molecules in cryo-EM images of cells using 2D template matching (2DTM). 2DTM is sensitive to small differences between a molecular model (template) and the detected structure (target). Here we use 2DTM to demonstrate that under the standard conditions used for machining lamellae of biological samples, FIB-milling introduces a layer of variable damage that extends to a depth of 60 nm from each lamella surface. This thickness exceeds previous estimates and limits the recovery of information for in situ structural biology. We find that the mechanism of FIB-milling damage is distinct from radiation damage during cryo-EM imaging. By accounting for both electron scattering and FIB-milling damage, we find that FIB-milling damage will negate the potential improvements from lamella thinning beyond 90 nm.

SignificanceThe molecular mechanisms of biological macromolecules and their assemblies is often studied using purified material. However, the composition, conformation and function of most macromolecules depend on their cellular context, and therefore, must also be studied inside cells. Focused ion beam (FIB) milling enables cryogenic electron microscopy to visualize macromolecules in cells at close to atomic resolution by generating thin sections of frozen cells. However, the extent of FIB-milling damage to frozen cells is unknown. Here we show that Ga+ FIB-milling introduces damage to a depth of [~]60 nm from each lamella surface, leading to a loss of recoverable information of up to 20% in 100 nm samples. FIB-milling with Ga+ therefore presents both an opportunity and an obstacle for structural cell biology.
]]></description>
<dc:creator>Lucas, B. A.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:date>2023-02-03</dc:date>
<dc:identifier>doi:10.1101/2023.02.01.526705</dc:identifier>
<dc:title><![CDATA[Quantification of gallium cryo-FIB milling damage in biological lamella]]></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/cgi/content/short/2023.02.23.529826v1?rss=1">
<title>
<![CDATA[
Epigenetic regulation of innate immune genes and enhanced interleukin-10 expression underlie chronic subclinical Plasmodium chabaudi infection 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.02.23.529826v1?rss=1"
</link>
<description><![CDATA[
Subclinical (asymptomatic) parasitemia is very common amongst Plasmodium-infected individuals. The immunological mechanisms underlying subclinical parasitemia remain elusive. We investigated the immune regulatory mechanisms behind chronic asymptomatic Plasmodium infection using mice lacking humoral immunity ({micro}MT-/- mice). {micro}MT-/- mice became chronically infected, despite lacking outward signs of disease, and exhibited increased macrophage numbers, decreased dendritic and CD4 cells, massive hemozoin accumulation in the spleen and bone marrow, and inadequate hematopoiesis. These changes were accompanied by high circulating levels of interleukin-10 (IL-10), enhanced chromatin accessibility of the STAT3 promoter, and enhanced STAT3 binding to the IL-10 promoter in macrophages. Inhibition of IL-10 signaling, despite promoting parasite clearance, resulted in a proinflammatory response, weight loss, and mortality. These results suggest that epigenetic changes induced by chronic P. chabaudi infection lead to high levels of circulating IL-10, protecting chronically infected mice against an excessive inflammatory response to high levels of blood-stage parasites.

Author summaryMalaria is a life-threatening disease with a range of symptoms, and it is induced in humans by infections with different species of Plasmodium. Highly prevalent in endemic regions, asymptomatic Plasmodium infections are related to long-term exposure to the parasite due to multiple infections and have been demonstrated in human and mouse studies to be associated with elevated levels of IL-10. However, how IL-10 levels remain elevated in the circulation in individuals over the long term has not been determined. We used a mouse model of chronic asymptomatic Plasmodium infection to investigate the mechanisms by which IL-10 levels are elevated during chronic asymptomatic infection. Our results show that epigenetic changes in immune genes of myeloid origin could be responsible for the elevated levels of IL-10, and that IL-10 signaling protected chronically infected mice from a severe inflammatory response induced by the infection.
]]></description>
<dc:creator>de Souza Silva, L.</dc:creator>
<dc:creator>Nguyen, Y. A. H.</dc:creator>
<dc:creator>Monks, B. G.</dc:creator>
<dc:creator>Forconi, C. S.</dc:creator>
<dc:creator>Crabtree, J. N.</dc:creator>
<dc:creator>Rodriguez, T.</dc:creator>
<dc:creator>Tamburro, N. D. P.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:creator>Horvath, G. L.</dc:creator>
<dc:creator>Abdullah, Z.</dc:creator>
<dc:creator>Latz, E.</dc:creator>
<dc:creator>Caffrey, D. R.</dc:creator>
<dc:creator>Kurt-Jones, E.</dc:creator>
<dc:creator>Gazzinelli, R. T.</dc:creator>
<dc:creator>Fitzgerald, K. A.</dc:creator>
<dc:creator>Golenbock, D. T.</dc:creator>
<dc:date>2023-02-24</dc:date>
<dc:identifier>doi:10.1101/2023.02.23.529826</dc:identifier>
<dc:title><![CDATA[Epigenetic regulation of innate immune genes and enhanced interleukin-10 expression underlie chronic subclinical Plasmodium chabaudi infection]]></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/cgi/content/short/2023.02.22.529625v1?rss=1">
<title>
<![CDATA[
Broadly effective ACE2 decoy proteins protect mice from lethal SARS-CoV-2 infection 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.02.22.529625v1?rss=1"
</link>
<description><![CDATA[
As SARS-CoV-2 variants have been causing increasingly serious drug resistance problem, development of broadly effective and hard-to-escape anti-SARS-CoV-2 agents is in urgent need. Here we describe further development and characterization of two SARS-CoV-2 receptor decoy proteins, ACE2-Ig-95 and ACE2-Ig-105/106. We found that both proteins had potent and robust in vitro neutralization activities against diverse SARS-CoV-2 variants including Omicron, with an average IC50 of up to 37 pM. In a stringent lethal SARS-CoV-2 infection mouse model, both proteins lowered lung viral load by up to [~]1000 fold, prevented the emergence of clinical signs in >75% animals, and increased animal survival rate from 0% (untreated) to >87.5% (treated). These results demonstrate that both proteins are good drug candidates for protecting animals from severe COVID-19. In a head-to-head comparison of these two proteins with five previously-described ACE2-Ig constructs, we found that two of these constructs, each carrying five surface mutations in the ACE2 region, had partial loss of neutralization potency against three SARS-CoV-2 variants. These data suggest that extensively mutating ACE2 residues near the RBD-binding interface should be avoided or performed with extra caution. Further, we found that both ACE2-Ig-95 and ACE2-Ig-105/106 could be produced to gram/liter level, demonstrating the developability of them as biologic drug candidates. Stress-condition stability test of them further suggests that more studies are required in the future to improve the stability of these proteins. These studies provide useful insight into critical factors for engineering and preclinical development of ACE2 decoys as broadly effective therapeutics against diverse ACE2-utilizing coronaviruses.

Abstract ImportanceEngineering soluble ACE2 proteins that function as a receptor decoy to block SARS-CoV-2 infection is a very attractive approach to broadly effective and hard-to-escape anti-SARS-CoV-2 agents. This study here describes development of two antibody-like soluble ACE2 proteins that broadly block diverse SARS-CoV-2 variants including Omicron. In a stringent COVID-19 mouse model, both proteins successfully protected >87.5% animals from lethal SARS-CoV-2 infection. In addition, a head-to-head comparison of the two constructs developed in this study with five previously-described ACE2 decoy constructs were performed here. Two previously-described constructs with relatively more ACE2-surface mutations were found with less robust neutralization activities against diverse SARS-CoV-2 variants. Further, the developability of the two proteins as biologic drug candidates was also assessed here. This study provides two broadly anti-SARS-CoV-2 drug candidates and useful insight into critical factors for engineering and preclinical development of ACE2 decoy as broadly effective therapeutics against diverse ACE2-utilizing coronaviruses.

TweetTwo antibody-like ACE2 decoy proteins could block diverse SARS-CoV-2 variants and prevent animals from severe COVID-19.
]]></description>
<dc:creator>Lu, M.</dc:creator>
<dc:creator>Yao, W.</dc:creator>
<dc:creator>Li, Y.</dc:creator>
<dc:creator>Ma, D.</dc:creator>
<dc:creator>Zhang, Z.</dc:creator>
<dc:creator>Wang, H.</dc:creator>
<dc:creator>Tang, X.</dc:creator>
<dc:creator>Wang, Y.</dc:creator>
<dc:creator>Li, C.</dc:creator>
<dc:creator>Cheng, D.</dc:creator>
<dc:creator>Lin, H.</dc:creator>
<dc:creator>Yin, Y.</dc:creator>
<dc:creator>Zhao, J.</dc:creator>
<dc:creator>Zhong, G.</dc:creator>
<dc:date>2023-02-23</dc:date>
<dc:identifier>doi:10.1101/2023.02.22.529625</dc:identifier>
<dc:title><![CDATA[Broadly effective ACE2 decoy proteins protect mice from lethal SARS-CoV-2 infection]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-02-23</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2023.03.20.533459v1?rss=1">
<title>
<![CDATA[
Self-delivering CRISPR RNAs for AAV Co-delivery and Genome Editing in vivo 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.03.20.533459v1?rss=1"
</link>
<description><![CDATA[
Guide RNAs offer programmability for CRISPR-Cas9 genome editing but also add challenges for delivery. Chemical modification, which has been key to the success of oligonucleotide therapeutics, can enhance the stability, distribution, cellular uptake, and safety of nucleic acids. Previously, we engineered heavily and fully modified SpyCas9 crRNA and tracrRNA, which showed enhanced stability and retained activity when delivered to cultured cells in the form of the ribonucleoprotein complex. In this study, we report that a short, fully stabilized oligonucleotide (a "protecting oligo"), which can be displaced by tracrRNA annealing, can significantly enhance the potency and stability of a heavily modified crRNA. Furthermore, protecting oligos allow various bioconjugates to be appended, thereby improving cellular uptake and biodistribution of crRNA in vivo. Finally, we achieved in vivo genome editing in adult mouse liver and central nervous system via co-delivery of unformulated, chemically modified crRNAs with protecting oligos and AAV vectors that express tracrRNA and either SpyCas9 or a base editor derivative. Our proof-of-concept establishment of AAV/crRNA co-delivery offers a route towards transient editing activity, target multiplexing, guide redosing, and vector inactivation.
]]></description>
<dc:creator>Zhang, H.</dc:creator>
<dc:creator>Kelly, K.</dc:creator>
<dc:creator>Lee, J.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Cooper, D.</dc:creator>
<dc:creator>Panwala, R.</dc:creator>
<dc:creator>Chen, Z.</dc:creator>
<dc:creator>Gaston, N.</dc:creator>
<dc:creator>Newby, G. A.</dc:creator>
<dc:creator>Xie, J.</dc:creator>
<dc:creator>Liu, D. R.</dc:creator>
<dc:creator>Gao, G.</dc:creator>
<dc:creator>Wolfe, S. A.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Watts, J. K.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:date>2023-03-20</dc:date>
<dc:identifier>doi:10.1101/2023.03.20.533459</dc:identifier>
<dc:title><![CDATA[Self-delivering CRISPR RNAs for AAV Co-delivery and Genome Editing in vivo]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-03-20</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2023.04.14.536905v1?rss=1">
<title>
<![CDATA[
Engineering Nme2Cas9 Adenine Base Editors with Improved Activity and Targeting Scope 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.04.14.536905v1?rss=1"
</link>
<description><![CDATA[
Nme2Cas9 has been established as a genome editing platform with compact size, high accuracy, and broad targeting range, including single-AAV-deliverable adenine base editors. Here, we have engineered Nme2Cas9 to further increase the activity and targeting scope of compact Nme2Cas9 base editors. We first used domain insertion to position the deaminase domain nearer the displaced DNA strand in the target-bound complex. These domain-inlaid Nme2Cas9 variants exhibited shifted editing windows and increased activity in comparison to the N-terminally fused Nme2-ABE. We next expanded the editing scope by swapping the Nme2Cas9 PAM-interacting domain with that of SmuCas9, which we had previously defined as recognizing a single-cytidine PAM. We used these enhancements to correct two common MECP2 mutations associated with Rett syndrome with little or no bystander editing. Finally, we validated domain-inlaid Nme2-ABEs for single-AAV delivery in vivo.
]]></description>
<dc:creator>Bamidele, N.</dc:creator>
<dc:creator>Zhang, H.</dc:creator>
<dc:creator>Dong, X.</dc:creator>
<dc:creator>Gaston, N.</dc:creator>
<dc:creator>Cheng, H.</dc:creator>
<dc:creator>Kelly, K.</dc:creator>
<dc:creator>Watts, J. K.</dc:creator>
<dc:creator>Xie, J.</dc:creator>
<dc:creator>Gao, G.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:date>2023-04-14</dc:date>
<dc:identifier>doi:10.1101/2023.04.14.536905</dc:identifier>
<dc:title><![CDATA[Engineering Nme2Cas9 Adenine Base Editors with Improved Activity and Targeting Scope]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-04-14</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2023.06.21.545926v1?rss=1">
<title>
<![CDATA[
Genome-wide kinetic profiling of pre-mRNA 3' end cleavage 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.06.21.545926v1?rss=1"
</link>
<description><![CDATA[
Cleavage and polyadenylation is necessary for the formation of mature mRNA molecules. The rate at which this process occurs can determine the temporal availability of mRNA for subsequent function throughout the cell and is likely tightly regulated. Despite advances in high-throughput approaches for global kinetic profiling of RNA maturation, genome-wide 3 end cleavage rates have never been measured. Here, we describe a novel approach to estimate the rates of cleavage, using metabolic labeling of nascent RNA, high-throughput sequencing, and mathematical modeling. Using in-silico simulations of nascent RNA-seq data, we show that our approach can accurately and precisely estimate cleavage half-lives for both constitutive and alternative sites. We find that 3 end cleavage is fast on average, with half-lives under a minute, but highly variable across individual sites. Rapid cleavage is promoted by the presence of canonical sequence elements and an increased density of polyadenylation signals near a cleavage site. Finally, we find that cleavage rates are associated with the localization of RNA Polymerase II at the end of a gene and faster cleavage leads to quicker degradation of downstream read-through RNA. Our findings shed light on the features important for efficient 3 end cleavage and the regulation of transcription termination.
]]></description>
<dc:creator>Torres-Ulloa, L.</dc:creator>
<dc:creator>Calvo-Roitberg, E.</dc:creator>
<dc:creator>Pai, A. A.</dc:creator>
<dc:date>2023-06-22</dc:date>
<dc:identifier>doi:10.1101/2023.06.21.545926</dc:identifier>
<dc:title><![CDATA[Genome-wide kinetic profiling of pre-mRNA 3' end cleavage]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-06-22</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2023.07.05.547848v1?rss=1">
<title>
<![CDATA[
Dual targeting of hepatocyte DGAT2 and stellate cell FASN alleviates nonalcoholic steatohepatitis in mice. 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.07.05.547848v1?rss=1"
</link>
<description><![CDATA[
Nonalcoholic steatohepatitis (NASH) is a malady of multiple cell types associated with hepatocyte triglyceride (TG) accumulation, macrophage inflammation, and stellate cell-induced fibrosis, with no approved therapeutics yet available. Here, we report that stellate cell fatty acid synthase (FASN) in de novo lipogenesis drives the autophagic flux that is required for stellate cell activation and fibrotic collagen production. Further, we employ a dual targeting approach to NASH that selectively depletes collagen through selective stellate cell knockout of FASN (using AAV9-LRAT Cre in FASNfl/fl mice), while lowering hepatocyte triglyceride by depleting DGAT2 with a GalNac-conjugated, fully chemically modified siRNA. DGAT2 silencing in hepatocytes alone or in combination with stellate cell FASNKO reduced liver TG accumulation in a choline-deficient NASH mouse model, while FASNKO in hepatocytes alone (using AAV8-TBG Cre in FASNfl/fl mice) did not. Neither hepatocyte DGAT2 silencing alone nor FASNKO in stellate cells alone decreased fibrosis (total collagen), while loss of both DGAT2 plus FASN caused a highly significant attenuation of NASH. These data establish proof of concept that dual targeting of DGAT2 plus FASN alleviates NASH progression in mice far greater than targeting either gene product alone.
]]></description>
<dc:creator>Yenilmez, B.</dc:creator>
<dc:creator>Harney, S. M.</dc:creator>
<dc:creator>DiMarzio, C.</dc:creator>
<dc:creator>Kelly, M.</dc:creator>
<dc:creator>Min, K.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Bramato, B. M.</dc:creator>
<dc:creator>Jackson, S. O.</dc:creator>
<dc:creator>Reddig, K.</dc:creator>
<dc:creator>Kim, J. K.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Czech, M. P.</dc:creator>
<dc:date>2023-07-05</dc:date>
<dc:identifier>doi:10.1101/2023.07.05.547848</dc:identifier>
<dc:title><![CDATA[Dual targeting of hepatocyte DGAT2 and stellate cell FASN alleviates nonalcoholic steatohepatitis in mice.]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-07-05</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2023.07.26.550536v1?rss=1">
<title>
<![CDATA[
Challenges in identifying mRNA transcript starts and ends from long-read sequencing data 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.07.26.550536v1?rss=1"
</link>
<description><![CDATA[
Long-read sequencing (LRS) technologies have the potential to revolutionize scientific discoveries in RNA biology, especially by enabling the comprehensive identification and quantification of full length mRNA isoforms. However, inherently high error rates make the analysis of long-read sequencing data challenging. While these error rates have been characterized for sequence and splice site identification, it is still unclear how accurately LRS reads represent transcript start and end sites. Here, we systematically assess the variability and accuracy of mRNA terminal ends identified by LRS reads across multiple sequencing platforms. We find substantial inconsistencies in both the start and end coordinates of LRS reads spanning a gene, such that LRS reads often fail to accurately recapitulate annotated or empirically derived terminal ends of mRNA molecules. To address this challenge, we introduce an approach to condition reads based on empirically derived terminal ends and identified a subset of reads that are more likely to represent full-length transcripts. Our approach can improve transcriptome analyses by enhancing the fidelity of transcript terminal end identification, but may result in lower power to quantify genes or discover novel isoforms. Thus, it is necessary to be cautious when selecting sequencing approaches and/or interpreting data from long-read RNA sequencing.
]]></description>
<dc:creator>Calvo-Roitberg, E.</dc:creator>
<dc:creator>Daniels, R. F.</dc:creator>
<dc:creator>Pai, A. A.</dc:creator>
<dc:date>2023-07-27</dc:date>
<dc:identifier>doi:10.1101/2023.07.26.550536</dc:identifier>
<dc:title><![CDATA[Challenges in identifying mRNA transcript starts and ends from long-read sequencing data]]></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/cgi/content/short/2023.08.09.552615v1?rss=1">
<title>
<![CDATA[
Casein kinase II promotes piRNA production through direct phosphorylation of USTC component TOFU-4 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.08.09.552615v1?rss=1"
</link>
<description><![CDATA[
Piwi-interacting RNAs (piRNAs) are genomically encoded small RNAs that engage Piwi Argonaute proteins to direct mRNA surveillance and transposon silencing. Despite advances in understanding piRNA pathways and functions, how the production of piRNA is regulated remains elusive. Here, using a genetic screen, we identify casein kinase II (CK2) as a factor required for piRNA pathway function. We show that CK2 is required for the localization of PRG-1 and for the proper localization of several factors that comprise the  upstream sequence transcription complex (USTC), which is required for piRNA transcription. Loss of CK2 impairs piRNA levels suggesting that CK2 promotes USTC function. We identify the USTC component twenty-one-U fouled-up 4 (TOFU-4) as a direct substrate for CK2. Our findings suggest that phosphorylation of TOFU-4 by CK2 promotes the assembly of USTC and piRNA transcription. Notably, during the aging process, CK2 activity declines, resulting in the disassembly of USTC, decreased piRNA production, and defects in piRNA-mediated gene silencing, including transposons silencing. These findings highlight the significance of posttranslational modification in regulating piRNA biogenesis and its implications for the aging process. Overall, our study provides compelling evidence for the involvement of a posttranslational modification mechanism in the regulation of piRNA biogenesis.
]]></description>
<dc:creator>Mello, C.</dc:creator>
<dc:creator>ZHANG, G.</dc:creator>
<dc:creator>Zheng, C.</dc:creator>
<dc:creator>ding, y.-h.</dc:creator>
<dc:date>2023-08-10</dc:date>
<dc:identifier>doi:10.1101/2023.08.09.552615</dc:identifier>
<dc:title><![CDATA[Casein kinase II promotes piRNA production through direct phosphorylation of USTC component TOFU-4]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-08-10</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2023.09.20.558641v1?rss=1">
<title>
<![CDATA[
Single intravitreal administration of a tetravalent siRNA exhibits robust and efficient gene silencing in rodent and swine photoreceptors 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.09.20.558641v1?rss=1"
</link>
<description><![CDATA[
Inherited retinal dystrophies caused by dominant mutations in photoreceptor-expressed genes, are a major cause of irreversible vision loss. Oligonucleotide therapy has been of interest in diseases that conventional medicine cannot target. In the early days, small interfering RNAs (siRNAs) were explored in clinical trials for retinal disorders with limited success due to a lack of stability and efficient cellular delivery. Thus, an unmet need exists to identify siRNA chemistry that targets photoreceptor-expressed genes. Here we evaluated 12 different fully chemically modified siRNA configurations, where the valency and conjugate structure were systematically altered. The impact on retinal distribution following intravitreal delivery was examined. We found that the increase in valency (tetravalent siRNA) supports the best photoreceptor accumulation. A single intravitreal administration induces multi-months efficacy in rodent and porcine retinas while showing a good safety profile. The data suggest that this configuration can treat retinal diseases caused by photoreceptor-expressed genes with 1-2 intravitreal injections per year.
]]></description>
<dc:creator>Cheng, S.-Y.</dc:creator>
<dc:creator>Caiazzi, J.</dc:creator>
<dc:creator>Biscans, A.</dc:creator>
<dc:creator>Alterman, J. F.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>McHugh, N.</dc:creator>
<dc:creator>Hassler, M.</dc:creator>
<dc:creator>Jolly, S.</dc:creator>
<dc:creator>Giguere, D.</dc:creator>
<dc:creator>Cipi, J.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Punzo, C.</dc:creator>
<dc:date>2023-09-22</dc:date>
<dc:identifier>doi:10.1101/2023.09.20.558641</dc:identifier>
<dc:title><![CDATA[Single intravitreal administration of a tetravalent siRNA exhibits robust and efficient gene silencing in rodent and swine photoreceptors]]></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/cgi/content/short/2023.07.03.547552v1?rss=1">
<title>
<![CDATA[
Baited reconstruction with 2D template matching for high-resolution structure determination in vitro and in vivo without template bias 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.07.03.547552v1?rss=1"
</link>
<description><![CDATA[
Cryogenic electron microscopy (cryo-EM) has revolutionized structural biology, rapidly increasing the number of available molecular structures. Because of this, as well as advances in structure prediction, the focus of structural biology has begun to shift to studying macromolecular structures in their native cellular environment. A dominant feature of cryo-EM images is shot noise, making the identification of small particles of interest difficult. This is further compounded by structural noise if these particles are imaged against a background of other molecules, such as inside a cell. 2D template matching (2DTM) can be used to localize complexes with high precision, even in the presence of cellular background. Once localized, these particles may be averaged together in 3D reconstructions; however, regions included in the template may suffer from template bias, leading to inflated resolution estimates and making the interpretation of high-resolution features unreliable. We evaluate conditions that minimize template bias and show that molecular features not present in the template can be reconstructed at high resolution from targets found by 2DTM, extending prior work at low-resolution.

Moreover, we present a quantitative metric for template bias to aid the interpretation of 3D reconstructions calculated with particles localized using high-resolution templates and fine angular sampling.
]]></description>
<dc:creator>Lucas, B. A.</dc:creator>
<dc:creator>Himes, B. A.</dc:creator>
<dc:creator>Grigorieff, N.</dc:creator>
<dc:date>2023-07-03</dc:date>
<dc:identifier>doi:10.1101/2023.07.03.547552</dc:identifier>
<dc:title><![CDATA[Baited reconstruction with 2D template matching for high-resolution structure determination in vitro and in vivo without template bias]]></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/cgi/content/short/2022.01.30.478372v1?rss=1">
<title>
<![CDATA[
Condensation of a nuclear mRNA export factor regulates mRNA transport during stress 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2022.01.30.478372v1?rss=1"
</link>
<description><![CDATA[
Nuclear mRNA export via nuclear pore complexes is an essential step in eukaryotic gene expression. Although factors involved in mRNA transport have been characterized, a comprehensive mechanistic understanding of this process and its regulation is lacking. Here, we use single-RNA imaging in yeast to show that cells use mRNA retention to control mRNA export during stress. We demonstrate that upon glucose withdrawal the essential RNA-binding factor Nab2 forms RNA-dependent condensate-like structures in the nucleus. This coincides with a reduced abundance of the DEAD-box ATPase Dbp5 at the nuclear pore. Depleting Dbp5, and consequently blocking mRNA export, is necessary and sufficient to trigger Nab2 condensation. The state of Nab2 condensation influences the extent of nuclear mRNA accumulation and can be recapitulated in vitro, where Nab2 forms RNA-dependent liquid droplets. We hypothesize that cells use condensation to regulate mRNA export and to control gene expression during stress.

HighlightsO_LIThe nuclear poly(A)-binding protein Nab2 forms RNA-containing condensate-like structures upon glucose starvation and upon acute cellular depletion of the DEAD-box ATPase Dbp5
C_LIO_LIThe Nab2 multimerization interface but not the intrinsically disordered regions (IDRs) are essential for condensation in vitro and in vivo
C_LIO_LIGlucose stress leads to poly(A) RNA retention in the nucleus, which is affected by the state of the Nab2 condensate
C_LI
]]></description>
<dc:creator>Heinrich, S.</dc:creator>
<dc:creator>Hondele, M.</dc:creator>
<dc:creator>Marchand, D.</dc:creator>
<dc:creator>Derrer, C. P.</dc:creator>
<dc:creator>Zedan, M.</dc:creator>
<dc:creator>Oswald, A.</dc:creator>
<dc:creator>Uliana, F.</dc:creator>
<dc:creator>Mancini, R.</dc:creator>
<dc:creator>Grunwald, D.</dc:creator>
<dc:creator>Weis, K.</dc:creator>
<dc:date>2022-01-30</dc:date>
<dc:identifier>doi:10.1101/2022.01.30.478372</dc:identifier>
<dc:title><![CDATA[Condensation of a nuclear mRNA export factor regulates mRNA transport during stress]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2022-01-30</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2023.05.03.539244v1?rss=1">
<title>
<![CDATA[
Lactate transporter MCT1 in hepatic stellate cells promotes fibrotic collagen expression in nonalcoholic steatohepatitis 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.05.03.539244v1?rss=1"
</link>
<description><![CDATA[
Circulating lactate is a fuel source for liver metabolism but may exacerbate metabolic diseases such as nonalcoholic steatohepatitis (NASH). Indeed, haploinsufficiency of lactate transporter monocarboxylate transporter 1 (MCT1) in mice reportedly promotes resistance to hepatic steatosis and inflammation. Here, we used adeno-associated virus (AAV) vectors to deliver thyroxin binding globulin (TBG)-Cre or lecithin-retinol acyltransferase (Lrat)-Cre to MCT1fl/fl mice on a choline deficient, high fat NASH diet to deplete hepatocyte or stellate cell MCT1, respectively. Stellate cell MCT1KO (AAV-Lrat-Cre) attenuated liver type 1 collagen protein expression and caused a downward trend in trichrome staining. MCT1 depletion in cultured human LX2 stellate cells also diminished collagen 1 protein expression. Tetra-ethylenglycol-cholesterol (Chol)-conjugated siRNAs, which enter all hepatic cell types, and hepatocyte-selective tri-N-acetyl galactosamine (GN)-conjugated siRNAs were then used to evaluate MCT1 function in a genetically obese NASH mouse model. MCT1 silencing by Chol-siRNA decreased liver collagen 1 levels, while hepatocyte-selective MCT1 depletion by AAV-TBG-Cre or by GN-siRNA unexpectedly increased collagen 1 and total fibrosis without effect on triglyceride accumulation. These findings demonstrate that stellate cell lactate transporter MCT1 significantly contributes to liver fibrosis through increased collagen 1 protein expression in vitro and in vivo, while hepatocyte MCT1 appears not to be an attractive therapeutic target for NASH.
]]></description>
<dc:creator>Min, K.</dc:creator>
<dc:creator>Yenilmez, B.</dc:creator>
<dc:creator>Kelly, M.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>Elleby, M.</dc:creator>
<dc:creator>Lifshitz, L. M.</dc:creator>
<dc:creator>Raymond, N.</dc:creator>
<dc:creator>Tsagkaraki, E.</dc:creator>
<dc:creator>Harney, S. M.</dc:creator>
<dc:creator>DiMarzio, C.</dc:creator>
<dc:creator>McHugh, N.</dc:creator>
<dc:creator>Bramato, B.</dc:creator>
<dc:creator>Morrison, B.</dc:creator>
<dc:creator>Rothstein, J. D.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:creator>Czech, M. P.</dc:creator>
<dc:date>2023-05-03</dc:date>
<dc:identifier>doi:10.1101/2023.05.03.539244</dc:identifier>
<dc:title><![CDATA[Lactate transporter MCT1 in hepatic stellate cells promotes fibrotic collagen expression in nonalcoholic steatohepatitis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-05-03</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2023.10.25.564061v1?rss=1">
<title>
<![CDATA[
Modular vector assembly enables rapid assessment of emerging CRISPR technologies 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.10.25.564061v1?rss=1"
</link>
<description><![CDATA[
The diversity of CRISPR systems, coupled with scientific ingenuity, has led to an explosion of applications; however, to test newly-described innovations in their model systems, researchers typically embark on cumbersome, one-off cloning projects to generate custom reagents that are optimized for their biological questions. Here, we leverage Golden Gate cloning to create the Fragmid toolkit, a modular set of CRISPR cassettes and delivery technologies, along with a web portal, resulting in a combinatorial platform that enables scalable vector assembly within days. We further demonstrate that multiple CRISPR technologies can be assessed in parallel in a pooled screening format using this resource, enabling the rapid optimization of both novel technologies and cellular models. These results establish Fragmid as a robust system for the rapid design of CRISPR vectors, and we anticipate that this assembly approach will be broadly useful for systematic development, comparison, and dissemination of CRISPR technologies.
]]></description>
<dc:creator>McGee, A. V.</dc:creator>
<dc:creator>Liu, Y. V.</dc:creator>
<dc:creator>Griffith, A. L.</dc:creator>
<dc:creator>Szegletes, Z. M.</dc:creator>
<dc:creator>Wen, B.</dc:creator>
<dc:creator>Kraus, C.</dc:creator>
<dc:creator>Miller, N. W.</dc:creator>
<dc:creator>Steger, R. J.</dc:creator>
<dc:creator>Escude Velasco, B.</dc:creator>
<dc:creator>Bosch, J. A.</dc:creator>
<dc:creator>Zirin, J. D.</dc:creator>
<dc:creator>Viswanatha, R.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:creator>Goodale, A.</dc:creator>
<dc:creator>Greene, M. A.</dc:creator>
<dc:creator>Green, T. M.</dc:creator>
<dc:creator>Doench, J. G.</dc:creator>
<dc:date>2023-10-27</dc:date>
<dc:identifier>doi:10.1101/2023.10.25.564061</dc:identifier>
<dc:title><![CDATA[Modular vector assembly enables rapid assessment of emerging CRISPR technologies]]></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/cgi/content/short/2023.10.21.563443v1?rss=1">
<title>
<![CDATA[
Addressing the dNTP bottleneck restricting prime editing activity 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.10.21.563443v1?rss=1"
</link>
<description><![CDATA[
Prime editing efficiency is modest in cells that are quiescent or slowly proliferating where intracellular dNTP levels are tightly regulated. MMLV-reverse transcriptase - the prime editor polymerase subunit - requires high intracellular dNTPs levels for efficient polymerization. We report that prime editing efficiency in primary cells and in vivo is increased by mutations that enhance the enzymatic properties of MMLV-reverse transcriptase and can be further complemented by targeting SAMHD1 for degradation.
]]></description>
<dc:creator>Ponnienselvan, K.</dc:creator>
<dc:creator>Liu, P.</dc:creator>
<dc:creator>Nyalile, T.</dc:creator>
<dc:creator>Oikemus, S.</dc:creator>
<dc:creator>Joynt, A. T.</dc:creator>
<dc:creator>Kelly, K.</dc:creator>
<dc:creator>Guo, D.</dc:creator>
<dc:creator>Chen, Z.</dc:creator>
<dc:creator>Lee, J. M.</dc:creator>
<dc:creator>Schiffer, C. A.</dc:creator>
<dc:creator>Emerson, C. P.</dc:creator>
<dc:creator>Lawson, N. D.</dc:creator>
<dc:creator>Watts, J. K.</dc:creator>
<dc:creator>Sontheimer, E. J.</dc:creator>
<dc:creator>Luban, J. J.</dc:creator>
<dc:creator>Wolfe, S. A.</dc:creator>
<dc:date>2023-10-21</dc:date>
<dc:identifier>doi:10.1101/2023.10.21.563443</dc:identifier>
<dc:title><![CDATA[Addressing the dNTP bottleneck restricting prime editing activity]]></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/cgi/content/short/2023.12.11.570495v1?rss=1">
<title>
<![CDATA[
Structural mechanism of angiogenin activation by the ribosome 
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</title>
<link>
https://biorxiv.org/cgi/content/short/2023.12.11.570495v1?rss=1"
</link>
<description><![CDATA[
Angiogenin, an RNase A-family protein, promotes angiogenesis and has been implicated in cancer, neurodegenerative diseases, and epigenetic inheritance. Upon activation during cellular stress, angiogenin cleaves tRNAs at the anticodon loop, producing nicked tRNA (also known as tRNA halves, tiRNAs or tsRNAs) and resulting in translation repression. The catalytic activity of isolated angiogenin, however, is very low, and the mechanisms of the enzyme activation and tRNA specificity have remained a puzzle. Here, we uncover these mechanisms using biochemical assays and cryogenic electron microscopy. Our work reveals that the cytosolic ribosome is the long-sought activator of angiogenin. A 2.8-[A] resolution cryo-EM structure features angiogenin bound in the A site of the 80S ribosome. The C-terminal tail of angiogenin is rearranged by interactions with the ribosome to activate the RNase catalytic center, making the enzyme several orders of magnitude more efficient in tRNA cleavage. Additional 80S*angiogenin structures capture how the tRNA substrate is directed by the ribosome next to angiogenins active site, demonstrating that the ribosome acts as the specificity factor. Our findings therefore suggest that angiogenin is activated by ribosomes with a vacant A site, whose abundance increases during cellular stresses.
]]></description>
<dc:creator>Loveland, A. B.</dc:creator>
<dc:creator>Koh, C. S.</dc:creator>
<dc:creator>Ganesan, R.</dc:creator>
<dc:creator>Jacobson, A.</dc:creator>
<dc:creator>Korostelev, A. A.</dc:creator>
<dc:date>2023-12-11</dc:date>
<dc:identifier>doi:10.1101/2023.12.11.570495</dc:identifier>
<dc:title><![CDATA[Structural mechanism of angiogenin activation by the ribosome]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-12-11</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2023.12.19.572404v1?rss=1">
<title>
<![CDATA[
A programmable dual-targeting di-valent siRNA scaffold supports potent multi-gene modulation in the central nervous system 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2023.12.19.572404v1?rss=1"
</link>
<description><![CDATA[
Di-valent short interfering RNA (siRNA) is a promising therapeutic modality that enables sequence-specific modulation of a single target gene in the central nervous system (CNS). To treat complex neurodegenerative disorders, where pathogenesis is driven by multiple genes or pathways, di-valent siRNA must be able to silence multiple target genes simultaneously. Here we present a framework for designing unimolecular "dual-targeting" di-valent siRNAs capable of co-silencing two genes in the CNS. We reconfigured di-valent siRNA - in which two identical, linked siRNAs are made concurrently - to create linear di-valent siRNA - where two siRNAs are made sequentially attached by a covalent linker. This linear configuration, synthesized using commercially available reagents, enables incorporation of two different siRNAs to silence two different targets. We demonstrate that this dual-targeting di-valent siRNA is fully functional in the CNS of mice, supporting at least two months of maximal target silencing. Dual-targeting di-valent siRNA is highly programmable, enabling simultaneous modulation of two different disease-relevant gene pairs (e.g., Huntingtons disease: MSH3 and HTT; Alzheimers disease: APOE and JAK1) with similar potency to a mixture of single-targeting di-valent siRNAs against each gene. This work potentiates CNS modulation of virtually any pair of disease-related targets using a simple unimolecular siRNA.
]]></description>
<dc:creator>Belgrad, J.</dc:creator>
<dc:creator>Tang, Q.</dc:creator>
<dc:creator>Hildebrand, S.</dc:creator>
<dc:creator>Summers, A.</dc:creator>
<dc:creator>Sapp, E.</dc:creator>
<dc:creator>Echeverria, D.</dc:creator>
<dc:creator>O'Reilly, D.</dc:creator>
<dc:creator>Luu, E.</dc:creator>
<dc:creator>Bramato, B.</dc:creator>
<dc:creator>Allen, S.</dc:creator>
<dc:creator>Cooper, D.</dc:creator>
<dc:creator>Alterman, J.</dc:creator>
<dc:creator>Yamada, K.</dc:creator>
<dc:creator>Aronin, N.</dc:creator>
<dc:creator>DiFiglia, M.</dc:creator>
<dc:creator>Khvorova, A.</dc:creator>
<dc:date>2023-12-19</dc:date>
<dc:identifier>doi:10.1101/2023.12.19.572404</dc:identifier>
<dc:title><![CDATA[A programmable dual-targeting di-valent siRNA scaffold supports potent multi-gene modulation in the central nervous system]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2023-12-19</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.01.05.574404v1?rss=1">
<title>
<![CDATA[
mRNA initiation and termination are spatially coordinated 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.01.05.574404v1?rss=1"
</link>
<description><![CDATA[
The expression of a precise mRNA transcriptome is crucial for establishing cell identity and function, with dozens of alternative isoforms produced for a single gene sequence. The regulation of mRNA isoform usage occurs by the coordination of co-transcriptional mRNA processing mechanisms across a gene. Decisions involved in mRNA initiation and termination underlie the largest extent of mRNA isoform diversity, but little is known about any relationships between decisions at both ends of mRNA molecules. Here, we systematically profile the joint usage of mRNA transcription start sites (TSSs) and polyadenylation sites (PASs) across tissues and species. Using both short and long read RNA-seq data, we observe that mRNAs preferentially using upstream TSSs also tend to use upstream PASs, and congruently, the usage of downstream sites is similarly paired. This observation suggests that mRNA 5 end choice may directly influence mRNA 3 ends. Our results suggest a novel "Positional Initiation-Termination Axis" (PITA), in which the usage of alternative terminal sites are coupled based on the order in which they appear in the genome. PITA isoforms are more likely to encode alternative protein domains and use conserved sites. PITA is strongly associated with the length of genomic features, such that PITA is enriched in longer genes with more area devoted to regions that regulate alternative 5 or 3 ends. Strikingly, we found that PITA genes are more likely than non-PITA genes to have multiple, overlapping chromatin structural domains related to pairing of ordinally coupled start and end sites. In turn, PITA coupling is also associated with fast RNA Polymerase II (RNAPII) trafficking across these long gene regions. Our findings indicate that a combination of spatial and kinetic mechanisms couple transcription initiation and mRNA 3 end decisions based on ordinal position to define the expression mRNA isoforms.
]]></description>
<dc:creator>Calvo-Roitberg, E.</dc:creator>
<dc:creator>Carroll, C. L.</dc:creator>
<dc:creator>Venev, S. V.</dc:creator>
<dc:creator>Kim, G.</dc:creator>
<dc:creator>Mick, S. T.</dc:creator>
<dc:creator>Dekker, J.</dc:creator>
<dc:creator>Fiszbein, A.</dc:creator>
<dc:creator>Pai, A. A.</dc:creator>
<dc:date>2024-01-07</dc:date>
<dc:identifier>doi:10.1101/2024.01.05.574404</dc:identifier>
<dc:title><![CDATA[mRNA initiation and termination are spatially coordinated]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2024-01-07</prism:publicationDate>
<prism:section></prism:section>
</item>
<item rdf:about="https://biorxiv.org/cgi/content/short/2024.03.21.586073v1?rss=1">
<title>
<![CDATA[
Traumatic injury causes selective degeneration and TDP-43 mislocalization in human iPSC-derived C9orf72-associated ALS/FTD motor neurons 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2024.03.21.586073v1?rss=1"
</link>
<description><![CDATA[
A hexanucleotide repeat expansion (HRE) in C9orf72 is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). However, patients with the HRE exhibit a wide disparity in clinical presentation and age of symptom onset suggesting an interplay between genetic background and environmental stressors. Neurotrauma as a result of traumatic brain or spinal cord injury has been shown to increase the risk of ALS/FTD in epidemiological studies. Here, we combine patient-specific induced pluripotent stem cells (iPSCs) with a custom-built device to deliver biofidelic stretch trauma to C9orf72 patient and isogenic control motor neurons (MNs) in vitro. We find that mutant but not control MNs exhibit selective degeneration after a single incident of severe trauma, which can be partially rescued by pretreatment with a C9orf72 antisense oligonucleotide. A single incident of mild trauma does not cause degeneration but leads to cytoplasmic accumulation of TDP-43 in C9orf72 MNs. This mislocalization, which only occurs briefly in isogenic controls, is eventually restored in C9orf72 MNs after 6 days. Lastly, repeated mild trauma ablates the ability of patient MNs to recover. These findings highlight alterations in TDP-43 dynamics in C9orf72 ALS/FTD patient MNs following traumatic injury and demonstrate that neurotrauma compounds neuropathology in C9orf72 ALS/FTD. More broadly, our work establishes an in vitro platform that can be used to interrogate the mechanistic interactions between ALS/FTD and neurotrauma.
]]></description>
<dc:creator>Martin, E. J.</dc:creator>
<dc:creator>Santacruz, C.</dc:creator>
<dc:creator>Mitevska, A.</dc:creator>
<dc:creator>Jones, I. E.</dc:creator>
<dc:creator>Krishnan, G.</dc:creator>
<dc:creator>Gao, F.-B.</dc:creator>
<dc:creator>Finan, J. D.</dc:creator>
<dc:creator>Kiskinis, E.</dc:creator>
<dc:date>2024-03-26</dc:date>
<dc:identifier>doi:10.1101/2024.03.21.586073</dc:identifier>
<dc:title><![CDATA[Traumatic injury causes selective degeneration and TDP-43 mislocalization in human iPSC-derived C9orf72-associated ALS/FTD motor neurons]]></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/cgi/content/short/2026.02.14.705883v1?rss=1">
<title>
<![CDATA[
Germline Blastomeres transcriptomics in the presence or absence of PIE-1 during C. elegans early embryogenesis 
]]>
</title>
<link>
https://biorxiv.org/cgi/content/short/2026.02.14.705883v1?rss=1"
</link>
<description><![CDATA[
In Caenorhabditis elegans (C. elegans) embryos, specification of the germ lineage relies on the maternal protein PIE-1. Here, we isolated somatic and germline blastomeres and performed specific transcriptomics in the presence or absence of PIE-1. These experiments enforce that PIE-1 maintains the identity of germline blastomeres by downregulating the accumulation of somatic RNAs but they also reveal a role for PIE-1 in sustaining the steady-state level of both maternally contributed as well as de novo transcribed germline-specific mRNAs in the early embryo. The present dataset represents a first blastomere-specific transcriptomic analyses of PIE-1 role and will serve as a comprehensive resource to highlight the mechanistic details of PIE-1 function in defining germline blastomere transcriptional identity.
]]></description>
<dc:creator>Ponsard, P.</dc:creator>
<dc:creator>Stubbe, F.-X.</dc:creator>
<dc:creator>Tricquet, P.</dc:creator>
<dc:creator>Mello, C.</dc:creator>
<dc:creator>Hermand, D.</dc:creator>
<dc:date>2026-02-14</dc:date>
<dc:identifier>doi:10.64898/2026.02.14.705883</dc:identifier>
<dc:title><![CDATA[Germline Blastomeres transcriptomics in the presence or absence of PIE-1 during C. elegans early embryogenesis]]></dc:title>
<dc:publisher>Cold Spring Harbor Laboratory Press</dc:publisher>
<prism:publicationDate>2026-02-14</prism:publicationDate>
<prism:section></prism:section>
</item>
</rdf:RDF>
