Results 326-350 of about 1,000
  1. Background Linking genetic perturbations to cellular phenotypes remains a central challenge in translational biology. Experimental iPSC and organoid models are powerful but constrained by scalability, variability, and difficulty modeling rare or polygenic states. Methods We developed aiAtlas v1.2 , a high-fidelity simulation platform that integrates Large Concept Model (LCM) logic with aiPSC-derived modeling. We evaluated 136 virtual cell lines spanning wild-type, single-mutation, multiple-mutation, human tumor-derived, and gene-fusion cohorts. Twenty-five features covering DNA damage/repair, replication stress, epigenetic remodeling, pluripotency, and stress responses were quantified. Statistical analysis used the Mann–Whitney U test with Bonferroni correction, Hodges–Lehmann estimators (HLE) for median differences, and Cliff’s delta effect sizes with bootstrap 95% confidence intervals . Robustness measures included early stopping, bagging, and 5-fold cross-validation. Results aiAtlas v1.2 reliably separated wild-type and mutant cohorts , revealing consistent disruptions in DNA damage accumulation, replication stress, epigenetic dysfunction, and loss of pluripotency, while identifying stable features (e.g., core nucleotide-excision repair processes and selected apoptosis measures). Subgroup analyses showed shared systemic effects and context-specific vulnerabilities : single mutations frequently produced measurable divergence; multiple mutations amplified instability; tumor-derived and gene-fusion lines yielded distinct but partially overlapping phenotypes. Large effect sizes (Cliff’s δ) with narrow bootstrap CIs supported reproducibility across cohorts. Conclusions/Impact aiAtlas v1.2 provides a robust virtual subject framework that uses aiCRISPR-Like (aiCRISPRL) virtual gene editing system that complements wet-lab CRISPR models by scaling to diverse genomic contexts and highlighting both disruption and stability. The platform can guide therapeutic prioritization, gene-editing strategy design, and regulatory innovation consistent with the FDA Modernization Act 2.0 , accelerating therapy development in rare diseases and cancer. Significance Statement aiAtlas introduces a scalable, reliable simulation framework that integrates advanced large concept model (LCM) logic with iPSC-derived cellular modeling. aiAtlas overcomes major limitations of experimental systems by capturing both broad and subgroup-specific phenotypic divergence across single mutations, multiple mutations, tumor-derived cell lines, and gene fusions. This reliable platform establishes a new opportunity for rare diseases and cancer modeling, offering reproducible insights that can accelerate discovery and translational applications where traditional wet-lab approaches are impractical. Furthermore, in situations where the target mutational profile has been defined but no cellular models yet exist, aiAtlas can quickly generate custom virtual cell lines that accurately reproduce the corresponding genomic and phenotypic features.
    Date: 2025-10-21
    Authors: Danter WR.
    Ref: bioRxiv
  2. Incompletely understood mechanisms serve to maintain Epstein-Barr virus (EBV) latency in most B-cell states, in which viral oncogene(s) are expressed but lytic antigens are repressed. Shortly after EBV’s discovery and even before it was named, early pioneers Werne and Gertrude Henle identified that restriction of extracellular arginine de-represses EBV lytic antigens within Burkitt lymphoma tumor cells. However, for nearly 60 years, it has remained unknown how arginine metabolism supports EBV latency. To gain insights, we performed an amino acid restriction screen in Burkitt cell lines. This confirmed that arginine restriction was sufficient to trigger EBV reactivation in Burkitt B-cells and gastric carcinoma models. Arginine restriction strongly impaired de novo pyrimidine biosynthesis, and CRISPR or chemical genetic blockade of pyrimidine biosynthesis enzymes induced EBV immediate early and early lytic gene expression. However, arginine restriction blocked EBV lytic DNA replication and consequently also late gene expression, suggesting an abortive lytic cycle. Arginine restriction triggered DNA damage, which was an important driver of arginine restriction-driven EBV reactivation. Arginine restriction and DNA hypomethylation synergistically increased EBV reactivation. Together, our results highlight arginine and pyrimidine metabolism as potential targets for EBV lytic antigen induction therapy in B and epithelial cell contexts. Importance Altered metabolism is a hallmark of cancer, frequently increasing transformed cell dependence on extracellular amino acid supply. Despite current interest in EBV lytic antigen induction therapy, in which viral lytic reactivation sensitizes tumors to the highly cytotoxic effects of the antiviral ganciclovir, there has been no systemic study of extracellular amino acid that controls EBV latency. We identified that arginine uptake was important for the maintenance of EBV latency in both Burkitt lymphoma and gastric carcinoma contexts. Metabolic pathway analyses highlighted that arginine uptake and metabolism was required to supply pyrimidines. Disruption of arginine metabolism or de novo pyrimidine synthesis caused DNA damage. As arginine restriction was also found to cause Burkitt DNA hypermethylation, we provide evidence that the combination of arginine restriction and DNA hypomethylation by decitabine or by CRISPR approaches together induced EBV reactivation more highly than either alone, suggesting a therapeutic approach.
    Date: 2025-10-21
    Authors: White S, Liao Y, Burton EM, Asara JM, Gewurz BE.
    Ref: bioRxiv
  3. Quantitative analysis in bacterial microscopy is often hindered by diverse cell morphologies, population heterogeneity, and the requirement for specialised computational expertise. To address these challenges, mAIcrobe is introduced as an opensource framework that broadens access to advanced bacterial image analysis by integrating a suite of deep learning models. mAIcrobe incorporates multiple segmentation algorithms, including StarDist, CellPose, and U-Net, alongside comprehensive morphological profiling and an adaptable neural network classifier, all within the napari ecosystem. This unified platform enables the analysis of a wide range of bacterial species, from spherical Staphylococcus aureus to rod-shaped Escherichia coli , across various microscopy modalities within a single environment. The biological utility of mAIcrobe is demonstrated through its application to antibiotic phenotyping in E. coli and the identification of cell cycle defects in S. aureus DnaA mutants. The modular design, supported by Jupyter notebooks, facilitates custom model development and extends AI-driven image analysis capabilities to the broader microbiology community. Building upon the foundation established by eHooke, mAIcrobe represents a substantial advancement in automated and reproducible bacterial microscopy.
    Date: 2025-10-21
    Authors: Brito AD, Alwardt D, Mariz BdP, Filipe SR, Pinho MG, Saraiva BM, Henriques R.
    Ref: bioRxiv
  4. Translational challenges in neuroscience originate from species-specific differences that limit the generalizability of experimental findings. Comparative approaches can help distinguish conserved from species-specific mechanisms, but their application has been limited by the lack of molecular tools beyond traditional model organisms, complicating direct comparisons of conserved and divergent mechanisms of neural function. This gap is particularly evident for the dopaminergic system, a key regulator of motivated behaviors across species and the principal pharmacological target for current psychotherapies. Building on our recent development of comparative gene editing, we here present an adeno-associated virus-mediated CRISPR/Cas9 strategy to reduce in vivo dopamine receptors D1 and D2 levels across the rodent phylogeny. Using this approach, we achieved specific reduction of receptor levels in three rodent species (house mouse, prairie vole, and Syrian hamster), which we demonstrate with radioactive ligand binding assays. This toolkit expands the reach of comparative gene editing approaches, enabling functional investigation of the dopaminergic system across rodent species. Thereby, it supports comparative neuroscience by facilitating the identification of conserved versus species-specific neural mechanisms with enhanced translational potential.
    Date: 2025-10-21
    Authors: Karkare SC, Aspesi D, Garner KM, Schut EH, Albers HE, Meye FJ, Murugan M, Boender AJ.
    Ref: bioRxiv
  5. ABSTRACT Long-read sequencing can characterize complex genome editing-induced DNA sequence changes such as large deletions, insertions, and inversions that are difficult to detect using short-read sequencing. However, PCR amplification and sequencing errors complicate accurate variant detection, and existing analysis tools are not optimized for gene editing specific allelic outcomes. Here we present CRISPRLungo, a computational pipeline specifically designed for long-read amplicon sequencing of gene edited samples. CRISPRLungo incorporates unique molecular identifier (UMI)-based error correction and statistical filtering to distinguish true editing events from background noise, enabling robust detection of small indels and structural variants. Through systematic benchmarking using simulated datasets, we demonstrate that CRISPRLungo outperforms existing approaches in both accuracy and read recovery. CRISPRLungo supports both Oxford Nanopore and PacBio platforms and identify previously undetected structural variant edits such as inversions in published CRISPR datasets. To demonstrate allele-specific edit quantification, we applied CRISPRLungo to analyze edited primary cells from a patient with harboring compound heterozygous SBDS mutations, accurately quantifying SBDS editing outcomes despite contaminating reads from the homologous SBDSP1 pseudogene. To maximize accessibility, we developed a fully client-side web application requiring no installation, making advanced long-read analysis accessible to researchers regardless of computational expertise. CRISPRLungo is freely available at https://github.com/pinellolab/CRISPRLungo with a user-friendly web interface available at https://pinellolab.github.io/CRISPRLungo .
    Date: 2025-10-21
    Authors: Hwang G, Vyshedskiy B, Barry T, Zeng J, Manis JP, Shimamura A, Bauer DE, Pinello L.
    Ref: bioRxiv
  6. Gene editing using CRISPR/Cas9 in vivo offers a powerful tool to investigate pain mechanisms. We validated the use of conditional knock-in mouse model expressing Streptococcus pyogenes CRISPR associated protein 9 selectively in sensory neurons by crossing with Scn10a -Cre driver. Transgene expression was confirmed in key tissues including the dorsal root ganglia (DRG) and sciatic nerve. To assess in vivo editing efficacy, RNA guides targeting GFP or TRPV1 were intrathecally administered. A dose of 3 µg RNA guides significantly reduced GFP expression, and two rounds of nanoparticle delivery targeting TRPV1 resulted in ∼65% reduction in DRG and ∼55% in sciatic nerve without triggering caspase-3-mediated apoptosis or motor deficits. Edited animals exhibited increased withdrawal latencies to heat and reduced nocifensive behaviors following capsaicin injection. Their responses to capsaicin-evoked thermal hyperalgesia and mechanical allodynia were diminished. This approach enables rapid and efficient sensory neuron-specific CRISPR/Cas9 gene perturbations for pain research in mice. We envisage that this method can be employed both for the exploration of molecular mechanisms underlying nociception and for the validation of therapeutic targets associated with pain.
    Date: 2025-10-21
    Authors: García G, Shapiro JB, Campbell ZT.
    Ref: bioRxiv
  7. New viral approaches have revolutionized neuroscience by precisely delivering genes in neurons; for example, to control or monitor activity in specific neuronal cell types. In contrast, the manipulation of oligodendrocytes requires the Cre-LoxP system and gene-by-gene engineering, breeding, and genotyping. Here we introduce OASIS ( O ligodendrocyte A AV-CRISPR mediated S pecific In vivo editing S ystem), a versatile platform that combines SELECTIV, an AAV-receptor-based transduction strategy, with HiUGE, an NHEJ-mediated CRISPR/Cas9 knock-in approach. We show efficient and specific oligodendrocyte transduction across the brain and tagging of endogenous cytoskeletal, myelin, cell adhesion, scaffolding, and junctional proteins. OASIS enables sparse yet reliable labeling, allowing direct visualization of a protein’s subcellular localization with single-cell resolution. We successfully fused the biotin-ligase TurboID with endogenous oligodendroglial Neurofascin-155, thereby achieving targeted biotinylation of the axoglial junction. OASIS is rapidly customizable for any gene-of-interest. Together, OASIS overcomes longstanding barriers in oligodendrocyte biology, providing a powerful system for precise, customizable genome editing and subcellular visualization in the adult brain.
    Date: 2025-10-21
    Authors: Ding X, Curtis JR, Xing Y, Wu Y, Peles E, Rasband MN.
    Ref: bioRxiv
  8. In hematology/oncology clinics, molecular diagnostics based on nucleic acid sequencing or hybridization are routinely employed to detect malignancy-associated genetic mutations and are instrumental in therapeutic stratification and prognostication. However, their limited cost-efficiency constrains their use in pre-malignant screening—specifically, the detection of rare circulating mutant blood cells in asymptomatic individuals. In both neonates and adults, the presence of malignancy-associated mutations in peripheral blood correlates with an elevated risk of future neoplastic transformation, with certain mutations, such as KMT2A rearrangements, exhibiting near-complete penetrance. If feasible, pre-malignant screening could enable early intervention and even disease prevention. Here, we introduce a high-throughput, single-cell computer vision platform capable of identifying mutant peripheral blood cells by recognizing mutation-specific morphological features. The morphology recognition module was developed through cross-species learning from murine to human datasets, enabling a generalizable and cost-effective approach for detecting mutations in live blood cells. The platform holds promise for translation into pre-malignant screening applications in asymptomatic neonates and adults as well as measurable residual disease monitoring in malignancies. Furthermore, it provides a novel single-cell morphological data modality that complements existing molecular layers, including genomics, epigenomics, transcriptomics, and proteomics.
    Date: 2025-10-21
    Authors: Khan SA, Faerber D, Kirkey D, Raffel S, Hadland B, Deininger M, Buettner F, Zhao HG.
    Ref: bioRxiv
  9. Complex microbial phenotypes involve the combined activity of diverse gene regulatory networks. However, the majority of reverse genetics approaches in microbial pathogenesis research have focused on single-gene perturbation studies, in part due to the lack of available genetic tools in many pathogens. Developing enhanced versions of CRISPR-Cas platforms holds significant promise for improving the scalability of microbial functional genomics research. Here, we demonstrate highly efficient, inducible, and multiplexed activation and repression in the major human fungal pathogen Candida albicans by translating the hyperdCas12a variant to the fungal kingdom. This represents the first application of a CRISPR-Cas12 system in a human fungal pathogen. We profile the effectiveness of our new CRISPRa and CRISPRi tools and achieve tunable levels of target modulation. Further, we demonstrate that perturbing combinations of genes in the drug efflux and ergosterol biosynthesis pathways reveals important redundancies and synergistic properties in drug resistance circuitry. Our hyperdCas12a platform is thus an efficient system for the rapid generation of combinatorial mutants that will enable the mechanistic understanding of genetic interactions involved in diverse phenotypes in C. albicans . The enhanced activity with hyperdCas12a in fungi suggests it could be translated to other microbes as a powerful tool for studying genetic interactions.
    Date: 2025-10-20
    Authors: Gervais NC, Rogers RK, Robin MR, Shapiro RS.
    Ref: bioRxiv
  10. SUMMARY Peripheral differentiation of regulatory T cells (pTregs) promoted by foreign antigens encountered in barrier tissues is considered a unique contributor to immunological tolerance to obligate non-self, like food or symbiotic microbes. The relative importance of adaptive recognition via the T cell receptor (TCR) vs environmental small-molecule or neuroimmune cues, is poorly understood. We leverage CRISPR-based TCR editing to perform in primary T cells in vivo , with a large panel of TCRs, a screen to assess pTreg differentiation induced by self, microbial, or dietary antigens. All antigen classes drive pTreg differentiation, which varies with the origin of the TCR: TCRs derived from Tregs enable pTreg differentiation much more effectively than those from Tconv. TCRs recognizing self, microbial, or dietary antigens elicit distinct pTreg phenotypes, Helios⁺, RORγ⁺, or both. Mechanistically, these trace to different types of antigen-presenting-cell involved. That Treg-derived TCRs preferentially drive tolerogenic fate speaks to preferential drivers of tolerogenic therapy.
    Date: 2025-10-20
    Authors: Chi X, Wang CH, Parisotto YF, Nyberg WA, Cabric V, Gelineau A, Cao Y, Owen DL, Ambjörnsson J, Mathis D, Eyquem J, Brown CC, Benoist C.
    Ref: bioRxiv
  11. ABSTRACT Chlorpyrifos (CPF) is a widely used organophosphate pesticide effective through inhibiting acetylcholinesterase, which leads to the accumulation of acetylcholine and continuous nerve stimulation. In addition to its well-known acute toxicity, exposure to CPF has also been linked to chronic conditions such as an increasing risk of autism spectrum disorder (ASD) and adverse effects on gut health, including disturbances to the gut microbiome and metabolism. However, the underlying mechanism of CPF’s contribution to ASD remains unclear, and the roles of the gut microbiome and gut metabolites in CPF-induced neurodevelopmental toxicity remain elusive. Using a high-throughput social behavior assay, we found that embryonic exposure to CPF induced lasting social deficits in zebrafish. Through a small-scale screen of common health beneficial gut microbiome metabolites, we discovered that butyrate effectively rescued CPF-induced social deficits. RNA sequencing of zebrafish brain tissues revealed that early exposure to CPF induced a lasting suppression of neuronal genes, including many ASD risk genes, and elevated expression of circadian genes. Butyrate partially reversed the suppression of key neuronal genes. Butyrate is a non-selective inhibitor of histone deacetylases (HDACs). Through a series of loss-of-function experiments utilizing CRISPR-Cas9-induced knockouts and selective chemical inhibitors, we found that the class I HDAC, HDAC1, most likely mediates butyrate’s rescue effect. Metabolomics analysis detected changes in several nitrogen metabolism-related pathways in the zebrafish gut following CPF exposure. Metagenomics analysis revealed an increase in abundance of the denitrifying bacteria Pseudomonas and a reduction in the nitric oxide-sensitive bacteria Aeromonas in the CPF-exposed zebrafish gut microbiome. Our results connect CPF-exposure with changes in the gut microbiome, metabolome, epigenetics, gene expression, and behavior, inspiring a novel hypothesis for the underlying molecular mechanisms of CPF-induced neurodevelopmental toxicity. In the long run, our findings may help elucidate how CPF exposure contributes to autism risk and inspire therapeutic developments.
    Date: 2025-10-20
    Authors: Diaz L, Kong AX, Zhang P, Chi J, Pham K, Johnson M, Eno A, Douglas I, Mao Y, MacDonald JW, Cui JY, Bammler T, Gu H, Geng Y.
    Ref: bioRxiv
  12. Abstract Orofacial clefts represent the most prevalent congenital anomalies affecting the craniofacial region. They can be evoked by a disturbed development of either oral epithelium or cranial neural crest-derived mesenchyme, or by disruptions of their interplay. IRF6 is a well-known risk gene associated with orofacial clefts. Its expression in the oral epithelium depends on the transcription factor AP-2α, encoded by TFAP2A. We here show by immunofluorescence on mouse embryonic sections and by mining of single cell RNA-seq data that IRF6 is also expressed in cranial neural crest-derived tissue in mice and humans, together with TFAP2A and SOX9. The IRF6 enhancer MCS-9.7 can be activated by the transcription factor SOX9, mutations of which cause Pierre Robin sequence, a craniofacial anomaly that includes cleft palate. This SOX9-dependent activation is influenced by the single nucleotide variant rs76145088 that is associated with orofacial clefting. Inactivation of Sox9 in a murine neural crest cell line by CRISPR/Cas9 results in loss of Irf6 expression. We conclude that dysregulation of the SOX9–IRF6 axis in cranial neural crest cells could be relevant for the pathogenesis of orofacial clefting.
    Date: 2025-10-20
    Authors: Weider M, Wagner MC, Schmid T, Gehlen-Breitbach S, Rodrian G, Peschel N, Schneider H, Ludwig KU, Wegner M, Gölz L.
    Ref: Research Square
  13. Summary Anti-CD19 chimeric antigen receptor (CAR)-T therapy induces profound remissions in lupus by depleting B cells, challenging the longstanding view that treatment-resistant disease is sustained by long-lived plasma cells. Additionally, emerging relapses highlight the need to understand how pathogenic autoantibodies arise. Using molecular antibody tagging in mice with human monogenic lupus variants, we reveal that autoantibody-producing cell cohorts are long-lived but plasma cells are short-lived, requiring continuous replenishment from proliferating precursors. The spleen acts as a major plasma cell reservoir, with perivascular localization conserved in mice and lupus patients. Relapse after anti-CD19 CAR-T occurred through newly-generated B cells rather than treatment-resistant clones. Plasma cell depletion by anti-BCMA CAR-T failed to eliminate some precursors that become autoantibody-secreting. These findings demonstrate that continuous B cell-to-plasma cell differentiation, not intrinsic plasma cell longevity, sustains pathogenic antibody responses in lupus, supporting a potential benefit of adjunctive therapies after CAR-T, particularly in genetically predisposed patients.
    Date: 2025-10-20
    Authors: Grenov A, Yoon J, Snell DM, Mikolajczak A, Wang H, Gürel E, Ronchel AR, Yegen G, Lee L, Esen BA, Rahman A, Maciocia P, Vinuesa CG.
    Ref: bioRxiv
  14. Nervous system development relies on sequential and coordinated formation of diverse neurons and glia from neural progenitor cells (NPCs). In the spinal cord, NPCs of the pMN domain produce neurons early in development followed by oligodendrocyte precursor cells (OPCs), which subsequently differentiate as oligodendrocytes (OLs), the myelinating glia of the central nervous system, later in development. The mechanisms that specify neural progenitor cells to the OL lineage are not yet well understood. Using zebrafish as an experimental model system, we generated single-cell RNA sequencing and single-nuclei ATAC sequencing data that identified a subpopulation of NPCs, called pre-OPCs, that appeared fated to produce OPCs. pre-OPCs uniquely express several genes that encode transcription factors specific to the OL lineage, including Gsx2, which regulates OPC formation in the mouse forebrain. To investigate Gsx2 function in zebrafish OPC specification, we used CRISPR/Cas9 genome editing to create gsx2 loss-of-function alleles. gsx2 homozygous mutant embryos initiated OPC formation prematurely and produced excess OPCs without altering OL differentiation. Using our single-nuclei multi-omics dataset, we predicted a gene regulatory network centered around gsx2 and identified genes that might be transcriptionally regulated by Gsx2. Taken together, our studies suggest that Gsx2 expression in pre-OPCs contributes to the timing of OPC specification.
    Date: 2025-10-19
    Authors: Arena KA, Kearns CA, Ahmed M, O’Rourke R, Sagerström CG, Franco SJ, Appel B.
    Ref: bioRxiv
  15. SUMMARY Transcriptional regulation of transposons and genes by TRIM28 and 5mC is critical for proper mammalian embryonic development, but the specific roles for these mediators in human embryonic and placental lineage remain unclear. We find that loss of TRIM28 has a limited effect on global transposon expression and instead results in upregulation of genes proximal to TRIM28-bound Long Terminal Repeats (LTRs) in both human trophoblast stem cells (hTSCs) and human embryonic stem cells (hESCs). MER11A elements show especially strong regulatory importance in hTSCs: these elements are bound by both TRIM28 and placental transcription factors and show both heterochromatic and euchromatic features. Some genes are positively regulated by MER11A elements in hTSC basal state, while other MER11A-proximal genes show upregulation only upon TRIM28 deletion. By contrast, loss of DNA methylation in hESCs or hTSCs leads to a global increase in transposon expression. While many genic 5mC targets are shared in hESCs and hTSCs, we also observe evidence that a handful of genes important for somatic development are repressed by 5mC in trophoblast, while a small parallel set of placental genes are repressed by methylation in embryonic tissue. Interestingly, loss of DNMT1 causes hESCs to be rapidly lost from culture in a TP53 and mitotic surveillance checkpoint-dependent manner, while hTSCs show little p53 response to DNMT1 loss or DNA damage generally, instead showing gradual mitotic defects and aneuploidy and slow loss from culture. This discrepancy may explain the higher frequency of karyotypic abnormality found in human placental cells. Together, this study charts the role of TRIM28 and DNA methylation in regulating embryonic and placental transcription and demonstrates divergent p53-dependent responses to genomic instability.
    Date: 2025-10-19
    Authors: Saini D, Katz MS, Beck SG, Ireland TE, Ray S, Niloy AJ, Mazloomnejad R, Fleming A, Vetrici SC, Cinkornpumin JK, Sack T, Duhamel S, Slim R, Park M, Frost JM, Paul S, Martin RC, Pastor WA.
    Ref: bioRxiv
  16. ABSTRACT ARGONAUTE (AGO) proteins associate with small RNAs to form RNA-induced silencing complexes (RISCs). Arabidopsis AGO1 effects post-transcriptional silencing by microRNAs (miRNAs) and small interfering RNAs (siRNAs) and is necessary for siRNA amplification through conversion of RISC target RNAs into double-stranded RNA by the RNA-dependent RNA Polymerase RDR6 and its mandatory cofactors SGS3 and SDE5. Many AGO proteins harbor hydrophobic pockets that interact with tryptophan residues, often surrounded by glycine (GW/WG), in intrinsically disordered regions (IDRs) of RISC cofactors. Here, we show that GW/WG dipeptides in the IDR of SGS3 and the hydrophobic pockets in AGO1 are required for fully functional RDR6-dependent siRNA amplification. We also show that this mechanism requires AGO1-specific structural elements, including positively charged residues surrounding the binding pockets, and a conserved, negatively charged patch in the IDR of SGS3. Thus, the same, conserved protein-protein interaction site is used for different purposes in distinct eukaryotic AGO proteins: the GW/WG-mediated TNRC6-Ago2 interaction is crucial for miRNA-guided silencing in metazoans whereas the GW/WG-mediated SGS3-AGO1 interaction facilitates siRNA amplification via RDR6 in plants.
    Date: 2025-10-18
    Authors: López-Márquez D, Arribas-Hernández L, Poulsen C, Oksbjerg ED, Bouteiller N, Meier M, Blanke J, del Espino A, Vigh ML, Bressendorff S, Carbonell A, Daucke R, Schoof EM, Vaucheret H, Brodersen P.
    Ref: bioRxiv
  17. The Danioninae subfamily of teleost fishes boasts up to four hundred distinct species that have evolved to display a stunning diversity of morphological forms. Here we use newly assembled genome sequences of four laboratory and wild zebrafish strains as well as eleven species of the Danio and Danionella genera to explore their phylogenetic history and the genetic basis of pigment pattern diversification. Phylogenomic analyses uncover extensive introgression and incomplete lineage sorting that have obscured phylogenetic relationships within Danio and corroborate an ancient hybrid origin of zebrafish. Whereas D. rerio inherited ancestral horizontal stripes, relatives repeatedly evolved spots and vertical bars. Interspecific complementation tests reveal functional divergence of the adhesion molecule gene igsf11 and the gap junction gene gja5b between the striped zebrafish and Danio species with divergent patterns. Comparative genomic and transcriptomic analyses suggest that protein and regulatory evolution have accompanied pigment pattern diversification. Our analyses elucidate complex genetic changes underlying the phylogenetic history and morphological diversification in the Danio genus. Resolved phylogenetic relationships, available genome assemblies, transcriptomes, and genetic tractability establish Danio fish species as excellent models for biomedical research in vertebrates.
    Date: 2025-10-18
    Authors: Lu J, Podobnik M, Huang J, McCluskey BM, McCarthy SA, Wood J, Collins J, Torrance J, Sims Y, Gao D, Huang J, Liu J, Fang W, Huang P, Ma C, Parichy D, Irion U, Liu J, Howe K, Postlethwait JH.
    Ref: bioRxiv
  18. Analyte detection through aptamer-induced signal generation by CRISPR-Cas enzymes has rapidly emerged as a popular biosensing approach. Here, we investigated the implementability and analytical performance of this setup for the detection of diverse small molecule analytes. We selected nine aptamers from the literature targeting seven analytes and tested a commonly used assay design whereby analyte binding by the aptamer liberates a short complementary DNA strand, which in turn activates Cas12a to generate a fluorescence signal. After extensive optimization, the assay functioned for only two of the seven analytes, and several previously reported results could not be reproduced. While Cas12a fluorescence detection was robust, the low success rate is likely due to aptamers not functioning reliably, underscoring the need for careful aptamer validation. Overall, our study provides a critical assessment of aptamer-Cas12a assay performances and discusses potential strengths, limitations, and pitfalls of this biosensing strategy.
    Date: 2025-10-17
    Authors: Brandenberg OF, Janssen EM, Schubert OT.
    Ref: bioRxiv
  19. ABSTRACT SauUSI is a dimeric, ATP-dependent Type IV restriction enzyme that protects Staphylococcus aureus by cleaving non-self DNA containing 5-methylcytosine or 5-hydroxymethylcytosine. Using biophysical, single-molecule, and nanopore sequencing methods, we show that 5-methylcytosine recognition first induces ATP-driven unidirectional translocation by one helicase-like subunit, displacing its target recognition domain (TRD). The partner TRD can then bind the liberated modified site, stabilizing a growing DNA loop. On symmetrically methylated DNA, both subunits engage in bidirectional loop translocation. Cleavage is triggered by binding a distal methylated site, by preferred DNA sequences, or upon reaching a DNA end. Interactions with other SauUSI dimers or protein roadblocks affect cleavage site distributions but are not required for nuclease activation. While the first cleavages principally generate blunt-ends or one-nucleotide 3′ overhangs, multiple binding-translocation cycles by individual enzymes ultimately shred the modified non-self DNA, neutralizing its threat.
    Date: 2025-10-16
    Authors: Shaw S, Hughes-Games A, Montaguth OT, McDowall S, Diffin F, Dunn D, Cross S, Szczelkun M.
    Ref: bioRxiv
  20. ABSTRACT Endometrial cancer is one of the main gynecological malignancies worldwide, with an estimated 320, 000 new cases annually. Several studies highlight ARHGAP35 as a significantly mutated gene in these tumors. It encodes for the protein p190RhoGAP-A (p190A), which is a major regulator of the small GTPase family of proteins. ARHGAP5 is a paralog of ARHGAP35 that encodes the protein p190RhoGAP-B (p190B). By analyzing human endometrial cancer samples, we found a co-occurrence of mutations in ARHGAP35 and ARHGAP5 genes and we reported that both are less expressed at the mRNA level in tumoral samples compared to healthy tissues. We were interested in understanding the impact of p190A/B under-expression in endometrial cancer and the relationship between the two paralogs. To do so, we have used CRISPR/Cas9 technology to generate HEC-1-A knockout cells for p190A and p190B. We showed that removal of each paralog led to a similar actin remodeling phenotype with the formation of Cross-Linked Actin Networks (CLANs), dependent on the Rho/ROCK pathway. Moreover, proteomic analysis of p190A and p190B knockout cells highlighted similar affected cell functions. Finally, our study demonstrates a synthetic lethality between p190A and p190B where removal of both paralogs is deleterious in endometrial cancer cells, unveiling a potential actionable vulnerability.
    Date: 2025-10-16
    Authors: Pinault M, Heraud C, Correia De Oliveira M, Neaud V, Valesco V, Prouzet-Mauleon V, Turcq B, Dupuy J, Raymond A, Croce S, Saltel F, Lagree V, Moreau V.
    Ref: bioRxiv
  21. ABSTRACT Newly-made secretory and membrane proteins exit the endoplasmic reticulum (ER) in COPII vesicles that form at specialised ER exit sites. These exit sites are typically near to the early Golgi compartments that receive these vesicles. A key player in the delivery of vesicles to the early Golgi is p115 (USO1), a homodimer with a folded head domain and a coiled-coil tail that is anchored to Golgi membranes. p115 has been shown to capture vesicles and to bind to SNARE proteins to promote membrane fusion. Here we report that the head domain of human p115 can bind directly to Sec16A, a large scaffolding protein that organises ER sites and promotes COPII vesicle formation. Structural prediction and deletion mapping define the region of interaction to a conserved motif in the unstructured N-terminal region of Sec16A, and mutations in p115 that block motif binding reduce the efficiency of secretion. This interaction could potentially allow a subset of p115 molecules to reach across from the early Golgi to the ER exit sites to contribute to the large-scale organisation of the early secretory pathway.
    Date: 2025-10-16
    Authors: Yakunin I, Gillingham AK, Pereira C, Gershlick DC, Munro S.
    Ref: bioRxiv
  22. APOE4 is the largest genetic risk factor for late-onset Alzheimer’s disease, but the cellular mechanisms by which APOE variants influence risk of disease remain incompletely understood. We have previously found that APOE4 expression led to the intracellular accumulation of lipid droplets in oligodendrocytes, causing decreased myelination. However, the mechanisms by which APOE4 alters lipid metabolism are not fully understood. Here, we leveraged a genome-wide CRISPR screen and ATAC-sequencing in human induced pluripotent stem cell (iPSC)-derived oligodendrocytes to dissect APOE4’s lipid-associated mechanisms of action. Using these approaches, we identified decreased Wnt signaling, and overactive GSK3b activity, as regulators of lipid droplet accumulation in oligodendrocytes. Genetic and pharmacological inhibition of GSK3b reduced lipid droplets in APOE4 oligodendrocytes, and increased myelination in three-dimensional iPSC-derived brain organoids. Finally, we show that pharmacological inhibition of GSK3b reduces lipid droplets and improves myelination in APOE4;PS19 Tau transgenic mice. Together, our results provide a framework for understanding the mediation of APOE4-related changes to oligodendrocyte lipid metabolism and myelination.
    Date: 2025-10-16
    Authors: Akay LA, Bright A, Boix CA, Louderback K, Medrano J, Sun D, Lin H, King O, Welch GM, Nawaid H, Agbas E, Jiang A, Bubnys A, Cheng J, Blanchard J, Tsai L.
    Ref: bioRxiv
  23. Bioscience encompasses studies on living organisms, their components, and their interactions, with the main aim of translating research into useful applications for medical, clinical, industrial, and environmental uses. The broad field of bioscience has witnessed tremendous growth in research output. This study was designed to evaluate the current trends in bioscience research using bibliometric approaches and develop future policy pointers following the innovative systems framework. Research articles focusing on bioscience published between 1883 and 2024 were sourced from the Scopus database. From the retrieved dataset, relevant articles were systematically screened and included for the analysis. Bibliometrix package, VOSviewer, and Microsoft Excel were used to analyze and visualize the parameters. 8,678 documents involving 30,380 authors from diverse institutions across the globe were published in 3,549 sources, with an annual rise of 4.41%. Exponential growth in bioscience research output was observed after 2007 and remained steady till 2024. The United States and China were leading nations for bioscience research. The most relevant affiliation was the University of California, United States, while the most relevant source was the Brazilian Journal of Medical and Biological Research , in terms of the number of publications. Among the authors, Wang Y had the highest number of documents, while the most impactful author was Zhang J. The most frequent keywords in bioscience research included biological research , genetics , procedures , metabolism , biology , DNA , gene expression , proteins , genomics , and fluorescence . Furthermore, themes such as bioinformatics , microRNA , synthetic biology, CRISPR/Cas9 , deep learning , multi-omics , and big data represented the recent research interests. The bioscience research landscape is defined by the dominance of high-income countries and a shift toward omics-driven and data-intensive approaches. Yet global participation remains uneven, with limited representation from low- and middle-income regions. This study highlights the need for inclusive, globally coordinated strategies that foster equitable access, capacity building, and cross-regional collaboration.
    Date: 2025-10-15
    Authors: Iroha OK, Palnam DW, Abraham P, Ogra IO, Johnson NK, Glen E, Joseph DN, Joshua SC, Wabba GP, Daji M, Tumba DE, Nathaniel M, Jonathan EU, Usman S, Luka MI, Sabale VB, Balogun EO, Opara UL.
    Ref: bioRxiv
  24. The aggregation of the protein alpha-synuclein (αSyn) is a common feature of multiple neurodegenerative diseases collectively called synucleinopathies, for which the pathobiology is not well understood. The different phenotypic characteristics of the synucleinopathies Parkinson’s disease (PD), Dementia with Lewy Bodies (DLB) and Multiple System Atrophy (MSA) have been proposed to originate from the distinct structures adopted by αSyn in its amyloid forms. Here, using covalent labeling and limited proteolysis coupled to mass spectrometry (LiP-MS) in vitro and in situ within neuronal cells and directly in native patient brain homogenates, we show that pathogenic αSyn from distinct synucleinopathies (PD, DLB and MSA) are structurally different. Further, we found that fibrillar structural differences are associated with different fibril interactomes and neuronal responses. We discovered disease-specific ubiquitination patterns and turnover profiles for pathogenic αSyn species, detected molecular pathways responding specifically to the uptake of different αSyn fibrillar polymorphs, and identified a subset of the involved proteins as candidate direct interactors of αSyn. In particular, components of the Ubiquitin-proteasomal System (UPS), including E3 ubiquitin ligases, chaperones, and Deubiquitinating proteins, showed disease/polymorph-specific interaction patterns, possibly accounting for different resistance of patient-derived αSyn fibrils to degradation. Genetic modulation with CRISPR-based tools showed that members of the UPS degradation pathway (three E3 ligases: UBE3A, TRIM25, HUWE1 and the AAA+ ATPase VCP) reduced αSyn inclusions, in a strain-specific manner. LiP-MS also identified sets of proteins with altered protease susceptibility in postmortem brain homogenates of PD, DLB, and MSA patients. These sets were largely disease-specific and included proteins altered in cells treated with fibrils derived from patients with the matching disease. Our findings provide insight into cellular processes involved in the accumulation and turnover of αSyn pathogenic aggregates in PD, DLB and MSA in a disease specific manner and constitutes a resource of potential novel drug targets in these synucleinopathies.
    Date: 2025-10-15
    Authors: Serdiuk T, Redeker V, Savistchenko J, Neupane S, Haenseler W, Fleischmann Y, Reber V, Keller S, Tiberi C, Bachmann-Gagescu R, Gstaiger M, Braun T, Riek R, Gentleman S, Aguzzi A, de Souza N, Melki R, Picotti P.
    Ref: bioRxiv
  25. Background Natriuretic peptides (NPs), encoded by the NPPA and NPPB genes, serve as both diagnostic biomarkers and cardioprotective hormones in heart failure. Their expression is tightly regulated by mechanical load, yet the upstream enhancer mechanisms translating hemodynamic stress into transcriptional activation remain incompletely understood. Methods We investigated the Nppa / Nppb super-enhancer (SE), which resides in a well-insulated topologically associating domain (TAD) and regulates stress-inducible expression of Nppa and Nppb . We applied CRISPR-based enhancer perturbation, chromatin accessibility and histone profiling, chromatin conformation assays, genetic mouse models, human iPSC-derived cardiomyocytes, and paired failing human hearts before and after left ventricular assist device (LVAD) unloading. Results Through integrative epigenomic and genetic analyses, we identified a conserved element, CR9, as a dominant hub enhancer within this SE. In neonatal rat cardiomyocytes, CRISPR-based activation and inhibition established that CR9 was both necessary and sufficient for NP induction, whereas neighboring elements (CR7/CR8) displayed modest activity but synergized with CR9, establishing a hierarchical and cooperative SE architecture. In vivo, CR9 deletion in mice markedly suppressed Nppa / Nppb expression and diminished chromatin accessibility and histone acetylation across adjacent enhancers and promoters, underscoring its structural as well as transcriptional role. Reinsertion of CR9, even in reverse orientation, restored transcription, confirming its orientation-independent activity. CR9 function remained confined within TAD boundaries, supporting a locus-specific regulation. RNAscope revealed spatial proximity between CR9 enhancer RNA and Nppa / Nppb nascent transcripts. Developmental profiling revealed a switch in enhancer usage from CR6/CR7 in the fetal heart to CR9 in adulthood, indicating a transition from developmental to stress-inducible regulation. In human induced pluripotent stem cell–derived cardiomyocytes, deletion of CR9 nearly abolished NPPA / NPPB expression, establishing its essential role in a human cellular context. Most notably, in paired human failing hearts before and after LVAD unloading, chromatin accessibility at CR9 was dynamically reversed, providing the first direct evidence that enhancer states are plastic and therapeutically modifiable in the human myocardium. Conclusions CR9 functions as a stress-inducible hub enhancer that coordinates NP transcription under pathological load. This enhancer exhibits reversible activation in human hearts, underscoring enhancer plasticity as a modifiable regulatory layer mediating stress-responsive transcriptional adaptation in the diseased myocardium. Clinical Perspective What is new? We identified CR9 as a stress-inducible hub enhancer within the Nppa / Nppb super-enhancer that is both necessary and sufficient for natriuretic peptide induction, defining a hierarchical and cooperative regulatory architecture controlling Nppa and Nppb expression. We uncovered a developmental switch in enhancer usage from CR6 in the fetal heart to CR9 in adulthood, revealing how stress-inducible enhancer activity emerges as the heart transitions from developmental to adaptive regulation. Using paired failing human hearts before and after LVAD unloading, we provide the first direct evidence that enhancer states are dynamically reversible in the human myocardium. What are the clinical implications? The reversibility of CR9 activity in human heart failure provides a molecular basis for how natriuretic peptide levels decrease when cardiac function improves with effective therapy, reflecting the underlying enhancer plasticity of the diseasesd myocardium. Enhancer plasticity is an emerging and targetable mechanism in heart failure, raising the possibility that stress-inducible enhancers like CR9 could be engineered to switch on cardioprotective genes when the heart is under stress, offering a new strategy for precision gene therapy.
    Date: 2025-10-15
    Authors: Matsuoka K, Inoue H, Jo H, Okamoto C, Hasuike H, Fu HY, Kioka H, Kuramoto Y, Segawa T, Nishimura S, Takamiya R, Miyashita Y, Asano Y, Yamazaki S, Kato H, Sakata Y, Takashima S, Tsukamoto O.
    Ref: bioRxiv
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