Biology subjects

Fu, X.

Publications and source records attributed to Fu, X..

At least 37 records · Page 2Linked to original sources

bioRxiv2026

Machine Learning Identifies Distinct Treg-Mediated Remodeling in HFpEF Hearts Treated with Neonatal Mesenchymal Stem Cells and Their Secretome

BackgroundHeart failure with preserved ejection fraction (HFpEF) remains a major therapeutic challenge due to its complex pathophysiology and pronounced heterogeneity. Regenerative approaches using neonatal mesenchymal stromal cells (nMSCs) and their secretome (SEC) have shown promise in other heart failure contexts. ObjectivesHowever, the effect of these therapies in HFpEF, and the underlying molecular mechanisms and causal pathways remain poorly understood. MethodsHFpEF was established in two distinct murine models, followed by treatment with either nMSCs or SEC. Functional and histological endpoints were assessed. We developed a novel machine learning framework, VIPcell, which integrates data augmentation, Partial Least Squares (PLS) regression, and causal structure inference to identify genes causally linked to cardiac function using single-nucleus RNA sequencing (snRNA-seq) data. VIPcell was applied to heart tissues from treated HFpEF animals to uncover key regulators of cardiac remodeling. ResultsBoth nMSC and SEC therapies significantly improved diastolic function in two independent rodent HFpEF models. These improvements were associated with reduced inflammation, attenuated myocardial fibrosis, and improved exercise capacity. Intercellular communication analysis revealed widespread, system-level signaling in nMSC-treated hearts, compared to more localized endothelial-cardiomyocyte crosstalk in SEC-treated hearts. Causal inference via VIPcell suggested overlapping upstream regulators in both treatment groups, particularly genes involved in regulatory T cell (Treg) biology and immunomodulatory signaling pathways, including FOXO signaling, NLRP3 inflammasome inhibition, and Tie2 activation. In vivo validation confirmed selective expansion of Tregs following nMSC and SEC therapy. In vitro, nMSCs induced significantly greater Treg expansion compared to multiple adult stem cell types. Critically, chemical depletion of Tregs abrogated the therapeutic effects of both treatments, establishing Tregs as central mediators of diastolic function recovery in the HFpEF preclinical model. ConclusionsnMSC and SEC therapies improve diastolic function in HFpEF through distinct remodeling mechanisms converging on Treg-mediated immune modulation. VIPcell supported identification of causal regulators, highlighting Treg-related signaling as a key driver of myocardial recovery in HFpEF. These findings offer mechanistic insight into cellular therapies for HFpEF and support the development of targeted, Treg-focused interventions.

physiology↗

bioRxiv2026

Multiomics reveals epigenetic control of fibroblast activity after myocardial infarction and a key role for RUNX transcription factors

BackgroundAfter myocardial infarction (MI), cardiac fibroblasts proliferate and undergo a sequential differentiation process. They first transition into cardiac myofibroblasts, a transient and highly contractile state, and ultimately into matrifibrocytes, a more stable state that partially resembles chondrocytes. These dynamic transitions are essential for infarct healing and scar formation. While insufficient fibroblast activation can compromise infarct integrity, excessive activation promotes pathological fibrosis that impairs cardiac function. Despite its clinical importance, the transcriptional and epigenetic regulation of these transitions remain poorly understood. Elucidating underlying mechanisms is critical for developing strategies to fine-tune fibroblast activity during cardiac repair. MethodsWe performed bulk RNAseq, ATACseq, CUT&Tag, CUT&RUN, EMseq, and Hi-C on cardiac fibroblasts from uninjured and post-MI mouse hearts. In parallel, we conducted single-nucleus multiomic (snRNAseq and snATACseq) profiling across multiple time points after MI. Subsequent integrated analysis explored epigenetic mechanisms regulating cardiac fibroblast gene expression and activity. Using an improved computational strategy, we constructed gene regulatory networks to identify key transcription factors and biological processes regulated by these transcription factors. To assess the role of Runx1 specifically, we used tamoxifen-inducible, fibroblast-specific Runx1 knockout mice to evaluate transcriptional, epigenetic, and functional outcomes with the same genomic tools and additional complementary assays. ResultsCardiac fibroblasts undergo extensive chromatin remodeling after MI, which is highly correlated with changes in transcriptomic profiles. In contrast, the role of DNA methylation is relatively minor. Gene regulatory network analysis identified Runx1 as a central regulator of cardiac fibroblast proliferation and matrifibrocyte differentiation. In vitro and in vivo validation confirmed Runx1 as a key modulator of transcriptional and epigenetic changes in cardiac fibroblasts. Runx1 KO reduced cardiac fibroblast proliferation, disrupted the myofibroblast-to-matrifibrocyte transition, and affected macrophage cytokine expression through altered cardiac fibroblast-macrophage communication. Fibroblast-specific Runx1 knockout mice showed improved post-MI survival and reduced cardiac dilatation, especially in males. Simultaneous Runx2 deletion further enhanced the effects of Runx1 knockout. ConclusionsCardiac fibroblast activation and differentiation after MI are regulated by dynamic epigenetic changes. Runx1 plays a pivotal role in modulating cardiac fibroblast activities, and its deletion improves cardiac repair by mitigating maladaptive fibroblast responses. By illuminating the centrality of Runx1 in post-MI repair, this study identifies an actionable pathway for therapeutically steering fibroblast responses.

genomics↗

bioRxiv2026

Gliomas preferentially develop within the action-mode network

Gliomas tend to arise in specific brain regions and may integrate into functional circuits, suggesting they could be regulated by brain activity. However, it remains unclear whether glioma growth is related to system-level brain networks. Analyzing neuroimaging data from three datasets including 1,310 patients with cerebral gliomas, we identified and replicated a functionally connected glioma network, which overlaps with the action-mode network (AMN), somatomotor network (SMN), and action-related subcortical regions. Resting-state functional connectivity (RSFC) of the AMN successfully predicted the location of glioma occurrence in two independent datasets with complex tumor distributions. Remarkably, no patient had a glioma entirely outside the AMN, and over 89% of patients exhibited gliomas with at least 50% overlap with the network. Moreover, the spatial overlap between glioma location and the AMN demonstrated significant prognostic value in survival analyses, with higher AMN-tumor overlap associated with poorer overall survival. Notably, the acetylcholine transporter, a key player in glioma pathogenesis that drives transcriptional reprogramming, showed an expression pattern overlapping with the AMN. Meta-analytic annotations further linked the glioma network to processes of action initiation, execution, and feedback. These findings indicate that gliomas preferentially arise in circuits involved in action and highlight the central role of the AMN in glioma pathophysiology and growth.

neuroscience↗

bioRxiv2025

LncRNA H19 Upregulation Links Hypoplastic Left Heart Syndrome to Impaired PINK1/Parkin-Mediated Mitophagy and Ischemic Vulnerability

BACKGROUNDThe myocardium in hypoplastic left heart syndrome (HLHS) exhibits immature metabolic programming, impaired mitochondrial quality control, and heightened susceptibility to ischemic and hypoxic injury during palliative surgery. The long non-coding RNA H19 suppresses translation of PTEN-induced putative kinase 1 (PINK1) mRNA and modulates mitochondrial quality control and ischemia/reperfusion injury (IRI) in adult hearts. Whether--and how--H19 regulates mitophagy and IRI in HLHS or in immature animals remains unknown. METHODSWe investigated H19 regulation and its role in mitophagy and ischemia/reperfusion or hypoxia/reoxygenation injury in myocardial tissue from HLHS patients, HLHS-specific induced pluripotent stem cell-derived cardiomyocytes (HLHS-iPSC-CMs), and immature rat hearts. Mechanistic interactions among H19, PINK1/Parkin signaling, and mitophagosome formation were assessed using loss-of-function approaches. RESULTSHLHS myocardium exhibited markedly elevated H19 expression, accompanied by reduced PINK1 and Parkin protein abundance and diminished mitophagosome formation. Similar findings were observed in HLHS-iPSC-CMs exposed to hypoxia/reoxygenation and in immature rat hearts subjected to myocardial IRI. H19 knockdown in HLHS-iPSC-CMs attenuated hypoxia/reoxygenation-induced lactate dehydrogenase release and restored PINK1 and Parkin protein levels. In immature rats, myocardial H19 silencing reduced infarct size, enhanced mitochondrial PINK1 and Parkin expression, and improved post-reperfusion cardiac function for up to 28 days. Conversely, knockdown of PINK1 or Parkin reduced mitophagosome formation and exacerbated functional deterioration during IRI. CONCLUSIONSH19 upregulation impairs PINK1/Parkin-dependent mitophagy and increases susceptibility to ischemic and hypoxic injury in HLHS and the immature heart. These findings identify H19 as a key regulator of mitochondrial quality control and a potential therapeutic target for mitigating IRI in early-life cardiac disease. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=134 SRC="FIGDIR/small/694773v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@193defdorg.highwire.dtl.DTLVardef@114ce7forg.highwire.dtl.DTLVardef@1010d05org.highwire.dtl.DTLVardef@1fdeac1_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical AbstractC_FLOATNO C_FIG Novelty and SignificanceO_ST_ABSWhat Is Known?C_ST_ABSO_LIThe myocardium in hypoplastic left heart syndrome (HLHS) exhibits immature metabolic programming, abnormal coronary perfusion, and impaired mitochondrial quality control, rendering it highly susceptible to ischemic and hypoxic injury. C_LIO_LIBoth structural limitations and intrinsic mitochondrial dysfunction contribute to the reduced ischemic tolerance of the HLHS heart, particularly during surgical and hemodynamic stress. C_LIO_LIThe long noncoding RNA H19 regulates mitochondrial quality control and modulates myocardial ischemia/reperfusion injury (IRI) in adult hearts. C_LIO_LIH19 inhibits the binding of the translation initiation factor eIF4A2 to PTEN-induced putative kinase 1 (PINK1) mRNA, thereby suppressing PINK1 protein synthesis and influencing PINK1-dependent mitophagy in adult mice. C_LI What New Information Does This Article Contribute?O_LIThis study identifies robust upregulation of H19 in HLHS myocardium, HLHS-specific induced pluripotent stem cell-derived cardiomyocytes (HLHS-iPSC-CMs) exposed to hypoxia/reoxygenation, and in immature rats subjected to myocardial IRI. C_LIO_LIElevated H19 is associated with suppressed PINK1/Parkin-dependent mitophagy, exacerbated IRI, and adverse post-injury remodeling. C_LIO_LIKnockdown of H19 restores mitochondrial PINK1 and Parkin protein levels, enhances mitophagy, reduces infarct size, and improves long-term recovery of cardiac function--demonstrating a previously unrecognized pathogenic role for H19 in the immature heart under stress. C_LIO_LIKnockdown of PINK1 or Parkin decreases mitophagosomes and exacerbates myocardial IRI in immature rats. C_LI

genomics↗

bioRxiv2025

Noradrenergic neuromodulation of cholecystokinin interneurons in the basolateral amygdala alters rhythmic activity and restrains fear memory

Norepinephrine (NE) release in the basolateral amygdala (BLA) during emotional arousal plays an essential role in the processing of fear. However, the cell type-specific NE neuromodulation of the fear circuit in the BLA has not been fully resolved. We reported previously a facilitation of fear memory by Gq-coupled receptor induction of repetitive bursting in parvalbumin-expressing interneurons and suppression of gamma oscillations in the BLA. Here, using patch clamp recordings, Cre-dependent DLX-driven intersectional targeting, and genetic manipulations, we demonstrate that NE also activates cholecystokinin (CCK)-expressing interneurons to generate synchronized trains of rhythmic CB1-sensitive IPSCs in BLA principal neurons via Gq-coupled 1A adrenoreceptor activation. The Gq-dependent mechanism in CCK interneurons is generalizable to chemogenetic Gq manipulation and Gq-coupled 5-HT2C serotoninergic receptor activation. We next tested the role of Gq neuromodulation of CCK interneurons in the regulation of BLA network activity associated with the behavioral expression of fear learning by rescued expression of 1A adrenoreceptors or chemogenetic Gq activation selectively in BLA CCK interneurons in a global 1A adrenoreceptor knockout mouse. Restoration of the rhythmic inhibitory synaptic activity via rescue of Gq-coupled receptor signaling in CCK interneurons enhanced LFP theta power in the BLA in vivo and decreased fear memory acquisition and recall. These data indicate an inhibitory role for CCK interneuron Gq signaling in fear learning via activation of patterned inhibitory synaptic input to principal neurons and enhanced theta oscillations in the BLA, and reveal a G protein-dependent, receptor-nonselective neuromodulatory mechanism in the BLA that regulates network and behavioral states.

neuroscience↗

bioRxiv2025

NanoBRET Tracer Development for Class I Bromodomain Target Engagement in Live Cells

Epigenetic reader proteins, such as bromo-domains, are often associated with diseases such as cancer and inflammation. BET bromodomain inhibitors have been studied extensively; however, non-BET bromodomains are understudied. Moreover, available high-throughput biological assays to assess inhibitors are limited. One non-BET bromodomain-containing protein, BPTF, has a recently reported inhibitor, BZ1, with an in vitro affinity of 6.3 nM. Additionally, BZ1 is known to be non-selective towards other class I bromodomains PCAF, GCN5, and CECR2. Here, we use a BZ1 analog, BZ1-THQ, to design a small molecule NanoBRET tracer, MS-1, for assessing inhibitor functional activity through live-cell target engagement against the BPTF bromodomain. Further, we investigate the versatility of MS-1 against PCAF, GCN5, and CECR2. We observe that MS-1 is a broadly applicable NanoBRET tracer for class I bromodomains, effectively binding BPTF, PCAF, GCN5, and CECR2 in HEK293T cells at low to sub-micromolar concentrations. We report EC50 values of commercially available and in-house inhibitors to demonstrate tracer versatility for future target engagement studies and inhibitor development. Table of Contents artwork O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=142 SRC="FIGDIR/small/689777v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@149371forg.highwire.dtl.DTLVardef@1c1e652org.highwire.dtl.DTLVardef@f81fbaorg.highwire.dtl.DTLVardef@1eb18f1_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

bioRxiv2025

Hidden-driver inference reveals synergistic brain-penetrant therapies for medulloblastoma

Effective therapies for high-risk medulloblastoma (MB), particularly MYC-driven Group 3 (G3) MB, remain elusive due to limited druggable mutations, poor blood-brain barrier (BBB) penetration, and rapid resistance. We developed SINBA (Synergy Inference by Data-driven Network-Based Bayesian Analysis), a systems biology framework that computationally prioritizes synergistic, BBB-permeable drug combinations by identifying hidden drivers sustaining oncogenic programs. Integrating MB-specific networks, transcriptomic data, and drug-gene interactions, SINBA nominated 32 candidates, of which 19 were experimentally validated as synergistic. Through iterative prioritization and experimental refinement, the MEK inhibitor mirdametinib and p38 inhibitor regorafenib emerged as the top brain-penetrant pair, suppressing G3 MB progression and extending survival in xenograft and immunocompetent models, with efficacy enhanced by low-dose radiation. Single-cell analysis revealed selective targeting of developmental origins and immune reprogramming. These findings establish SINBA as a computationally assisted discovery framework for clinically actionable combinations in high-risk MB.

cancer biology↗

bioRxiv2025

Multimodal AI Decodes Extreme Environment Functional Dark Matter Beyond Homology

Functional annotation of proteins from extreme environments represents a major bottleneck for bioresource discovery, as a vast reservoir of functional dark matter defies existing homology-based methods. We demonstrate that environmental pressures impart conserved physicochemical energy signatures that co-determine protein function with sequence and structure. Here we developed ACCESS, a multimodal graph neural network employing hierarchical contrastive learning with a tailored label-sample co-embedding to fuse energy, sequence, and structural information and overcome homology scarcity. ACCESS surpasses state-of-the-art methods including BLASTp and CLEAN in annotating low-identity enzymes. Applied to extreme environmental metagenomics, we constructed a function map of extremophile enzymes to expand the biocatalyst library, pinpointed functionally critical residues to guide rational design, and enabled large-scale, function-based macro-evolutionary analyses. This paradigm transcends the limitations of homology, illuminating protein dark matter and accelerating the exploration of the biospheres functional diversity for applications in biotechnology and therapeutic development.

bioinformatics↗

bioRxiv2025

Establishment and functional characterization of bovine endometrial epithelial organoids

Pre-implantation embryonic loss constitutes a major barrier to reproductive efficiency in livestock, yet the extrinsic determinants of embryonic survival remain poorly defined. Intra-organoid fluid (IOF) faithfully recapitulates native tissue secretions across multiple organ systems. We hypothesized that bovine endometrial epithelial organoids (BEEO) would produce IOF that mirrored in vivo uterine luminal fluid composition and extend embryo culture duration in vitro. We pursued three objectives: (a) establish and morphologically characterize BEEO, (b) define BEEO transcriptomic and secretory responses to estradiol (E2), medroxyprogesterone acetate (MPA), and interferon-tau (IFN{tau}), and (c) determine whether BEEO-derived IOF can support in vitro embryonic development beyond Day 8 (hatched blastocyst stage) under conventional culture conditions. BEEO were established from primary endometrial tissue (n=4) and maintained a stable epithelial phenotype through multiple passages. Transcriptomic profiling revealed robust responses to stimulation, with E2, MPA, and IFN{tau} inducing distinct gene expression programs consistent with in vivo effects. IOF metabolomic analysis confirmed hormone-dependent regulation of IOF secretory output, with E2+MPA (diestrus mimic) enhancing the production of metabolites implicated in conceptus development. Remarkably, IOF from diestrus mimic-stimulated BEEO, despite being diluted approximately seven-fold in PBS, maintained embryo survival rates comparable to optimized commercial medium, and exceeded PBS-only controls. These findings position BEEO as a physiologically relevant model for dissecting maternal-embryo interactions in vitro and identifying targets to improve fertility in cattle and other livestock.

cell biology↗

bioRxiv2025

HGS+ enlarged vesicular compartment serves as site for coronavirus assembly at later infection stage

The precise site of coronavirus assembly remains poorly characterized. In this study, we observed that coronavirus infection induces the host factor hepatocyte growth factor-regulated tyrosine kinase substrate (HGS) to form distinct HGS enlarged vesicular compartments at later infection stage. Confocal and live-cell super-resolution microscopy showed that viral structural proteins colocalize with these HGS enlarged vesicular compartments. Correspondingly, APEX2-based electron microscopy (APEX2-EM) and immuno-EM analyses confirmed the presence of assembled virions within these unique HGS compartments, identifying them as sites of virion assembly. This was further supported by cryogenic correlated light and electron microscopy (cryo-CLEM), which captured ongoing virion formation occurring within HGS enlarged vesicles. Crucially, whole cell volume EM revealed that HGS deficiency abolishes these vesicular compartments and markedly reduces assembled virions. Lastly, we demonstrated that HGS vesicular compartments are rearranged from Golgi and endosome/lysosome by coronavirus infection. Together, these findings establish that coronavirus-induced HGS vesicular compartments function as essential platforms for virion assembly at later infection stage.

microbiology↗

bioRxiv2025

Cooperative and antagonistic interactions between sub-clones favour the co-existence of multiple resistance mechanisms in melanoma

Intra-tumour heterogeneity is a major obstacle to durable responses to targeted cancer therapy, yet how different resistant cell states interact within the same tumour remains poorly understood. In this study, we demonstrate cooperativity between co-occurring resistant states in a single tumour. Using BRAF mutant melanoma as a paradigm, we generate three different resistant states within a single model and demonstrate that they exhibit varying differentiation states and migratory capacities and share few common therapeutic vulnerabilities. Through a combination of experiments, including using Cre-mediated recombination to generate heterogeneity in existing tumours, and in silico modelling, we show that intra-tumour heterogeneity is the most favoured state for therapy resistant tumours. This is underpinned by signalling between different melanoma states, with YAP1 active cells providing supporting signals for other cells but inhibiting their own proliferation. Optimal disease control requires targeting both the YAP1 active cell state and the inter- cellular communication networks. We identify the histone demethylase inhibitor GSK-J4 as being particularly effective in targeting both features of resistant tumours and demonstrate its ability to control melanoma with multiple concurrent resistance mechanisms.

cancer biology↗

bioRxiv2025

Cell migration sculpts evolutionary dynamics favouring therapy resistance in lung cancer

The evolution of cancer undermines the long-term efficacy of therapy. In this study, we combine experimental, computational, and clinical data analysis to investigate factors influencing the competition of subclones in lung cancer. Lineage tracing reveals unexpected variation in the long-term fate of neutral subclones, with subclones arising near the edge of tumours being favoured. Low levels of cell migration and cell mixing lead to high cell densities in the interior of the tumour that suppress proliferation. Using agent-based modelling and in silico analysis we inferred the extent of cell mixing in human tumours from the TRACERx lung cancer study. This reveals correlations between Epithelial to Mesenchymal Transition (EMT), stromal fibroblasts and levels of cell mixing. Experimental analysis confirms that both TGF{beta}-driven EMT and stromal fibroblasts reduce the variability in subclone fate and promote subclone mixing. Moreover, mixing favours clonal sweeps by subclones resistant to therapy-induced cell killing. Together, these analyses demonstrate that EMT and stromal fibroblasts sculpt tumour evolution by promoting cell mixing and thereby favour the rapid dominance of therapy resistant subclones.

cancer biology↗

bioRxiv2025

Multimodal learning decodes the global binding landscape of chromatin-associated proteins

The identity of a cell is governed by regulatory proteins binding to the genome to control gene expression. Mapping these genome-wide binding events across thousands of proteins and cell types is essential for understanding development and disease at scale, yet has remained a major experimental and computational barrier. Here we present Chromnitron, a multimodal foundation model that learns the rules of protein-DNA binding from protein sequence, DNA sequence, and context-specific chromatin states. Unlike prior single-task and multi-task learning approaches, Chromnitron implements a multimodal learning framework that accurately predicts the binding landscape for proteins and cell types not seen during training. Using Chromnitron, we discovered and experimentally validated new protein regulators of T cell exhaustion. Chromnitron also uncovered previously uncharacterized dynamic shifts in the binding landscape of regulatory proteins during neurogenesis. This marks a critical step toward a predictive model of interpretable gene regulatory programs across cell types, enabling rapid discovery of regulatory circuits and identification of new therapeutic targets.

systems biology↗

bioRxiv2025

Targeting von Willebrand factor selectively under inflammatory conditions

It is challenging to develop anti-thrombotic therapeutics to treat or prevent pathological thrombus formation without increasing the risk of bleeding. Currently available anti-coagulant drugs render blood thinner irrespective of whether an inflammatory pro-thrombotic condition exists or whether clotting needs to occur because of traumatic vessel rupture. It is desirable to develop a drug that is active only under the oxidizing conditions present during inflammation. The blood protein von Willebrand factor (VWF) plays a key role in initiating blood clotting and it has been the target of anti-thrombotic therapies. It has been shown that oxidizing agents released during inflammation activate VWF by converting methionine residues within its domains to methionine sulfoxide. A previous study by us developed a method to computationally screen for drugs that inhibit VWF more strongly in the presence of oxidizing conditions. The computations suggested in particular a drug, lumacaftor, that could inhibit VWF function selectively in the presence of oxidized methionine residues. Here, we developed an enzyme-linked immunosorbent assay to test the effect of drugs on the ability of VWF to bind to the platelet surface receptor glycoprotein Ib comparing oxidizing and non-oxidizing conditions. The results indicate that lumacaftor may indeed have the desired properties of inhibiting VWF selectively when oxidized. Because of its simplicity, the assay provides a high-throughput method to efficiently screen multiple drugs against VWF in both its oxidized and unoxidized state.

biochemistry↗

bioRxiv2025

Commensal taxa in gut microbiota limit antibiotic resistance during extended oral antibiotic use

Certain bacterial infections, such as those involving prosthetics, can require antimicrobial therapy over months to years, potentially increasing the burden of antimicrobial resistance. Here we longitudinally track the antimicrobial resistome in mice during continuous antibiotic dosing over 21 months. The burden of antibiotic resistance genes (ARGs) initially increases, but, surprisingly, declines in later months, approaching levels observed in untreated animals. ARG burden is regulated by taxonomy and declines as ARG-harboring taxa that initially bloom are replaced by commensals. Furthermore, we find that the dynamics of antibiotic-induced ARG burden are influenced by age-related differences in microbial taxonomy and can be removed by fecal microbiota transplantation. We show that commensals may regulate the resistome by limiting the growth of ARG-harboring taxa, thereby providing antimicrobial expansion resistance.

microbiology↗

bioRxiv2025

Genetic inactivation of the Translin/Trax RNase activity alters small RNAs including miRNAs, disrupts gene expression and impairs distinct forms of hippocampal synaptic plasticity and memory

Neurons utilize RNA interference in the reversible translational repression of synaptically localized mRNAs, enabling rapid translation in response to synaptic activity. Two evolutionarily conserved proteins, Translin and Trax, form an RNase complex which processes miRNAs, tRNAs and siRNAs. To determine the specific role of the RNase activity of this complex in brain function, we employed a mouse line harboring a point mutation in Trax (E126A) that renders the Translin/Trax RNase inactive. At the molecular level, we found alterations in the levels of multiple small RNAs including miRNAs, tsRNAs and substantial downregulation of gene expression at the mRNA level in the hippocampus of TraxE126A mice. At the synaptic level, TraxE126A mice exhibit deficits in specific forms of long-term hippocampal synaptic plasticity. At the behavioral level, TraxE126A mice display impaired long-term spatial memory and altered open-field and acoustic-startle behavior. These studies reveal the functional role of Translin/Trax RNase in the mammalian brain.

neuroscience↗

bioRxiv2025

Genomic Touchstone: Benchmarking Genomic Language Models in the Context of the Central Dogma

The emergence of genomic language models (gLMs) has revolutionized the analysis of genomic sequences, enabling robust capture of biologically meaningful patterns from DNA sequences for an improved understanding of human genome-wide regulatory programs, variant pathogenicity and therapeutic discovery. Given that DNA serves as the foundational blueprint within the central dogma, the ultimate evaluation of a gLM is its ability to generalize across this entire biological cascade. However, existing evaluations lack this holistic and consistent framework, leaving researchers uncertain about which model best translates sequence understanding into downstream biological prediction. Here we present Genomic Touchstone, a comprehensive benchmark designed to evaluate gLMs across 36 diverse tasks and 88 datasets structured along the central dogmas modalities of DNA, RNA, and protein, encompassing 5.34 billion base pairs of genomic sequences. We evaluate 34 representative models encompassing transformers and convolutional neural networks, as well as emerging efficient architectures such as Hyena and Mamba. Our analysis yield four key insights. First, gLMs achieve comparable or superior performance on RNA and protein tasks compared to models pretrained on these molecules. Second, transformer-based models continue to lead in overall performance, yet efficient sequence models show promising task-specific capabilities and deserve further exploration. Third, the scaling behavior of gLMs remains incompletely understood. While longer input sequences and more diverse pretraining data consistently improve performance, increases in model size do not always translate into better results. Fourth, pretraining strategies, including the choice of training objectives and the composition of pretraining corpora, exert substantial influence on downstream generalization across different genomic contexts. Genomic Touchstone establishes a unified evaluation framework tailored to human genomics. By spanning multiple molecular modalities and biological tasks, it offers a valuable foundation for guiding future gLM design and understanding model generalizability in complex biological contexts.

bioinformatics↗

bioRxiv2025

Oviduct fluid metabolic regulation of embryonic genome methylation

Adverse maternal health and lifestyle during pregnancy can program offspring susceptibility to noncommunicable diseases in adulthood. Oviduct fluid facilitates key preimplantation milestones, including embryonic genome activation. However, the regulatory mechanisms governing oviduct fluid composition, and the developmental consequences of its disruption, remain unclear. Capitalizing on conserved dynamics between human and bovine embryonic genome activation, we first established and characterized bovine oviduct epithelial organoids as a model system. Organoids were then exposed to {Delta}-tetrahydrocannabinol (THC) and cannabidiol (CBD) to test the hypothesis that exocannabinoids alter intra-organoid fluid composition. Treatment altered the organoid transcriptome and intra-organoid fluid metabolome, notably elevating 5'-deoxyadenosine levels. Subsequent embryo culture with 5'-deoxyadenosine during embryonic genome activation resulted in aberrant DNA methylation patterning - independently of direct THC and CBD exposure. These findings identify a novel, indirect, mechanism by which maternal exposures disrupt embryonic development through changes in oviductal metabolite secretions. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=149 SRC="FIGDIR/small/659599v1_ufig1.gif" ALT="Figure 1"> View larger version (56K): org.highwire.dtl.DTLVardef@19ac750org.highwire.dtl.DTLVardef@935709org.highwire.dtl.DTLVardef@13723a8org.highwire.dtl.DTLVardef@105f473_HPS_FORMAT_FIGEXP M_FIG Graphical Abstract C_FIG

cell biology↗