Biology subjects

Zeng, L.

Publications and source records attributed to Zeng, L..

At least 19 recordsLinked to original sources

bioRxiv2026

Dysregulation of miR-103a-3p/AGFG1 axis links endocytic trafficking dysfunction to ER stress in Parkinson's disease

Background: Parkinson's disease is defined by progressive dopaminergic neurodegeneration and -synuclein pathology. Endoplasmic reticulum (ER) stress and clathrin-mediated endocytosis dysfunction are implicated in disease pathogenesis, but the molecular mechanisms connecting these processes remain poorly understood. Here, we investigate a miR-103a-3p/AGFG1 axis as a regulator link between endocytic trafficking and ER stress in Parkinson's disease. Methods: MiR-103a-3p and AGFG1 were examined in plasma and postmortem substantia nigra from patients with Parkinson's disease and controls. Gain- and loss-of-function studies, target validation and live-cell imaging were used to define the role of the miR-103a-3p/AGFG1 axis in ER stress and endocytic trafficking. The pathway was further investigated in SNCA A53T and LRRK2 G2019S hiPSC-derived neurons. Therapeutic targeting of AGFG1 was evaluated using antisense oligonucleotides (ASOs) in vitro and in a 6-hydroxydopamine mouse model. Results: MiR-103a-3p was significantly reduced in Parkinson's disease plasma and substantia nigra, whereas AGFG1 was increased in nigral tissue. MiR-103a-3p directly repressed AGFG1 and attenuated thapsigargin-induced ER stress, while miR-103a-3p inhibition or AGFG1 overexpression exacerbated stress signalling. AGFG1 knockdown reversed the effects of miR-103a-3p inhibition, establishing AGFG1 as a functional downstream effector. Mechanistically, AGFG1 associated and co-trafficked with clathrin-positive vesicles, whereas ER stress progressively disrupted AGFG1-clathrin vesicle dynamics, revealing an association between endocytic trafficking and stress signalling. In genetic Parkinson's disease models, SNCA A53T and LRRK2 G2019S neurons showed mutation-dependent differences in AGFG1 expression and stress regulation. eIF2 phosphorylation increased in both SNCA A53T and LRRK2 G2019S neurons, whereas AGFG1 and GADD34 upregulation was selective to SNCA A53T neurons. Importantly, ASO-mediated AGFG1 suppression attenuated ER stress in vitro and preserved nigral dopaminergic neurons with improved motor performance in vivo. Conclusion: Our findings identify the miR-103a-3p/AGFG1 axis as a previously unrecognised molecular link between endocytic trafficking dysfunction and ER stress in Parkinson's disease, and support AGFG1 as a mechanistically potential therapeutic target.

neuroscience↗

bioRxiv2026

PIEZO1 marks a low neuroendocrine state and supports cisplatin tolerance in small cell lung cancer

Small cell lung cancer (SCLC) is initially sensitive to platinum chemotherapy, yet resistant disease frequently develops with altered neuroendocrine (NE) identity. The mechanisms linking these cell states to treatment tolerance remain incompletely understood. Here, we integrate chemoresistant cell models with patient bulk multiomics, single-cell and spatial transcriptomic data to investigate the mechanosensitive channel PIEZO1. In H69AR cells, PIEZO1 upregulation accompanied loss of NE markers and enrichment of mesenchymal programmes; increased PIEZO1 expression and reduced cisplatin sensitivity were also observed in H446DDP cells. Across patient-derived data sources, PIEZO1 was associated with low NE activity within malignant populations, despite its substantially higher abundance in vascular and stromal cells. State-blind CNV analyses and cross-sectional state ordering supported a cell-state association that was only weakly explained by detectable subclones and varied with hypoxia across models. Spatial analyses localized PIEZO1-rich signals to stromal and vascular interface regions, while composition-adjusted tumour-core analyses showed little residual covariance with tumour programmes. PIEZO1 depletion reduced intracellular calcium-associated signals and cisplatin IC50 and increased drug-induced apoptosis. Conversely, Yoda1 increased calcium signals and cisplatin tolerance in parental cells. Patient light-chain phosphorylation, YAP localization and partial pharmacological reversal by verteporfin supported an actomyosin-YAP-linked mechanism. PIEZO1 depletion also reduced SMAD2/3 and mesenchymal-associated readouts. Finally, transcript enrichment profiles and PIEZO1-IGF2BP2 covariation nominated a potential m6A regulatory layer. Together, these findings identify PIEZO1 as a low-NE state-associated marker and contributor to cisplatin tolerance, and motivate a calcium-cytoskeleton-YAP model for further mechanistic testing.

cancer biology↗

bioRxiv2026

Sotagliflozin Reprograms Hepatic Lipid Metabolism and Attenuates Atherosclerosis Beyond Empagliflozin in CKM Mice

Background: Sodium-glucose cotransporter-2 (SGLT2) inhibitors reduce cardiovascular mortality and chronic kidney disease (CKD) progression in cardiovascular-kidney-metabolic (CKM) syndrome, but this benefit derives primarily from reductions in heart failure and cardiovascular mortality rather than in atherothrombotic events. Sotagliflozin, which inhibits both intestinal SGLT1 and renal SGLT2, is the only drug in this class shown to lower rates of myocardial infarction and stroke in CKD. However, its mechanism remains unclear, and its effectiveness in non-diabetic CKD has not been studied. We hypothesized that dual SGLT1/2 inhibition reprograms systemic substrate utilization toward fatty acid oxidation, which may partially account for this protective effect. Methods: CKD was induced in male low-density lipoprotein receptor-deficient mice by 5/6 nephrectomy. Sham and CKD mice received a high-fat diet and drinking water containing sotagliflozin, empagliflozin, or vehicle for 16 weeks, at doses that produced equivalent fractional excretion of glucose. We quantified atherosclerosis en face and in the aortic sinus. Indirect calorimetry, echocardiography, hepatic RNA sequencing, plasma acylcarnitine profiling, and in vivo deuterium labeling of palmitate were performed. Results: At matched levels of glucosuria and plasma total cholesterol, sotagliflozin decreased body mass, atherosclerosis burden, triglycerides, and TNF- more than empagliflozin, and raised postprandial total GLP-1 approximately 3-fold, while both drugs similarly improved albuminuria and diastolic function. Sotagliflozin increased energy expenditure independent of body mass and lowered respiratory exchange ratio despite compensatory hyperphagia. Sotagliflozin reduced hepatic lipogenic genes and de novo lipogenic flux, while increasing {beta}-oxidation and ketogenesis; empagliflozin only activated the oxidative pathway. Conclusions: In experimental CKM syndrome, dual SGLT1/2 inhibition reduces atherosclerosis and metabolic syndrome more effectively than selective SGLT2 inhibition and is associated with reprogramming of hepatic lipid metabolism. These results suggest that sotagliflozin could be an attractive candidate for mitigating atherosclerotic risk in non-diabetic CKD.

pharmacology and toxicology↗

bioRxiv2026

Loss of DNA Demethylase Enhances Arsenic Resistance Via Reducing of PIN2 Antisense Long Noncoding RNA

DNA methylation dynamics regulate diverse plant stress responses, but the mechanisms governing arsenic (As) tolerance through epigenetic pathways remain largely unknown. Here we report that Arabidopsis mutants lacking the DNA demethylase, REPRESSOR OF SILENCING (ROS1), show substantially enhanced As resistance. Integrating transcriptome and methylome data, we found that PIN-FORMED 2 (PIN2), encoding an auxin efflux carrier that also transports As out of cells, represents a key ROS1 target. In ros1, we observed increased methylation in the last exon of PIN2, a region functioning as the promoter for an antisense long non-coding RNA (lncRNA). Hypermethylation of the promoter suppresses the antisense lncRNA, which follows reduction of sense PIN2 transcription. As a result, PIN2 expression increases in ros1 mutants during As exposure, enhancing As tolerance. Analysis of ros1 pin2 double mutants confirmed that PIN2 acts downstream of ROS1 in As tolerance. Our study demonstrates an epigenetic pathway in which ROS1 regulates As tolerance by controlling PIN2 expression through antisense lncRNA-mediated transcriptional interference, offering new epigenetic strategies using plants in heavy metal contaminated environments.

plant biology↗

bioRxiv2026

The HES1-SOD1 Antagonism Shapes Senescence Heterogeneity and Impacts Metastatic Relapse of Circulating Tumor Cells

Circulating tumor cells (CTCs) encounter multiple challenges within the blood microenvironment, including oxidative stress, flow shear forces, and immune surveillance, often leading to anoikis. Recently, a transitional state of CTC senescence has been identified, contributing to metastatic inefficiency. However, the molecular mechanisms linking senescent CTCs to disease relapse remain to be defined. By integrating a genetic model of cortactin knockdown-induced CTC senescence with single-cell multi-omic analyses, we revealed two distinct senescent CTC subpopulations marked by HES1 expression levels. These HES1low and HES1high subpopulations exhibited differential evolutionary trajectory dynamics and unique molecular and metabolic signatures, which were significantly correlated with adverse clinical outcome across several patient cohorts. HES1low senescent CTCs displayed enhanced mitochondrial fitness, oxidative phosphorylation, and ROS-detoxifying capabilities, resulting in more efficient tumor regrowth with a pro-inflammatory and thrombotic phenotype when compared to the HES1high group. Mechanistically, HES1 directly bound to the Sod1 promoter and repressed its expression, leading to redox imbalance and mitochondrial dysfunction that were linked to weakened tumor regrowth capacity. Both senescent CTC subpopulations were broadly resistant to cytotoxic and targeted therapies, yet they showed elevated dependency on anti-apoptosis programs that make them susceptible to dual blockade by SOD1 inhibitor and the anti-senolytic drug ABT737 in vivo. Finally, in a prospective cohort of on-treatment melanoma patients, HES1 senescent CTCs were highly enriched in patients with progressive disease. Thus, the HES1-SOD1 antagonism shapes CTC senescence heterogeneity and contributes to differential tumor relapse, which can be therapeutically explored for eliminating residual metastatic disease.

cancer biology↗

bioRxiv2026

Extracellular matrix particle treatment induces digit regeneration in soft-tissue preserved amputation (SPA) model of adult mice

BackgroundIn mouse classic amputation model, second phalanx (P2) is incapable of regeneration. Extracellular matrix (ECM) solution has shown limited ability to induce digit regeneration in classical amputation model of the murine digit. However, the effect of solid ECM particles on bone regeneration is not well understood due to difficulties in treating solid particles in classical amputation model. MethodsWe examined the regenerative effects of ECM particles in mice digit by establishing a soft tissue preserved amputation (SPA) model on P2, through removing the amputated bone whilst preserving soft tissue. ECM particles implanted into the amputation site and wrapped in the preserved soft tissues. Bone regeneration was assessed by morphological examination and micro-CT scans. ResultsWe observed bone regeneration in the SPA model; specifically, new bone formed at the P2 distal end. Implantation of ECM particles exerted a pro-regenerative effect, characterized by increased bone volume and decreased bone density. Moreover, the ECM induced the formation of free-floating bone, further supporting its role in bone regeneration. Combined treatment with ECM particles and bone morphogenetic protein 2 (BMP2) resulted in a significant increase in bone volume. ConclusionsWe demonstrate that soft tissue preservation at the amputation site can overcome the intrinsic regenerative limitationsl. Using SPA model, we found that ECM particles have a proven ability to promote bone regeneration, and that the combination of ECM particles with BMP2 further enhances bone regeneration. These findings underscore the therapeutic promise of ECM-based strategies, for clinical translation in non-regenerative finger injuries. Summary statementSolid-state Extracellular matrix can induce mice digit regeneration and has the potential for clinical application. HighlightsThe SPA model we developed enables ECM particles to adhere to wounds, and our research has found that: O_LIDigit bone regeneration was shown in SPA model . C_LIO_LIECM particles treatment promoted bone regeneration and can generate free-floating bone in SPA model. C_LIO_LICombination of ECM + BMP2 treatment induced strong digit regeneration in SPA model. C_LI

cell biology↗

bioRxiv2026

Immunometabolic Reprogramming by Thyroid-Stimulating Antibodies Drives Orbital Adipogenesis via Histone Lactylation in Thyroid Eye Disease

Thyroid eye disease (TED) is conventionally viewed as an autoimmune inflammatory disorder. However, the metabolic determinants driving orbital tissue remodeling remain largely undefined. Here, we uncover a paradigm-shifting mechanism whereby thyroid-stimulating antibodies (TSAbs) instigate profound metabolic reprogramming in orbital fibroblasts (OFs), driving a switch toward glycolysis and markedly elevating lactate production via the CREB/LDHA axis. Critically, we demonstrate that this TSAbs-induced metabolic perturbation is not a mere byproduct but the principal driver of pathology. Mechanistically, lactate functions as a signaling metabolite that directly potentiates adipogenesis via histone lactylation-dependent transcriptional activation of the master adipogenic regulators PPAR{gamma} and C/EBP. Collectively, our findings underscore metabolic reprogramming as a central pathogenic mechanism in TED, whereby autoimmune cues drive disease progression through metabolic-epigenetic crosstalk. This work substantiates the paradigm of TED as an immune- metabolic disorder.

immunology↗

bioRxiv2026

Decoding the oxytocinergic and behavioral signatures of milk ejection

Oxytocin-mediated milk ejection (ME) is pivotal to effective breastfeeding and productive health, yet behaviorally decoding and revealing neural mechanisms of ME remains challenging. Here, we combined in vivo calcium imaging and intramammary pressure recording to uncover the temporal connections between episodic activity of oxytocin neurons and ME in conscious lactating rats. Leveraging the association and behavioral responses in dam and pup, we developed a supervised machine learning framework (ME Decoder) to enable automated analyses of ME. Inspired by its interpretable features, we defined the activity-coupled dam-pup interactions (ADPI), manifested by high kyphosis of the dam followed by pup treading and stretch, as the behavioral signatures of ME. By ME Decoder and ADPI analyses, we detected reduced ME but unaffected activity of oxytocinergic neurons after systemic blockade of oxytocin receptor. Our study uncovers the oxytocinergic and behavioral signatures of ME and provides a generalizable approach for further investigation.

neuroscience↗

bioRxiv2026

Benthic diatoms navigate shear flows via hydrodynamic rolling and active gliding

Navigating fluid flow is a fundamental challenge for microbial life across diverse aquatic environments. While rheotaxis in swimming microorganisms has been extensively studied, it remains unresolved whether near-bed shear merely perturbs gliding motility or instead provides directional cues for active navigation on surfaces. Here we show that the benthic diatom Navicula cryptocephala utilises a purely mechanical strategy to achieve downstream rheotaxis and anisotropic spreading on submerged surfaces. Single-cell ellipsoidal tracking reveals a direction-dependent angular response that reorients gliding cells towards the downstream direction. Using interference reflection microscopy, we further reveal that shear induces rolling of obliquely gliding cells, laterally shifting the cell-substrate contact site. This shift renders raphe-based propulsion non-collinear with substrate friction, generating a downstream-restoring yaw torque. Crucially, our results rule out alternative explanations based on longitudinal shifts of the raphe contact site or direct hydrodynamic yaw torque. A minimal stochastic model confirms that this mechanical reorientation alone is sufficient to reproduce the observed drift and diffusion patterns, without invoking either orientation-dependent switching between motility states or orientation-dependent dwell times of those states. Our findings uncover a mechanism by which ambient shear is converted into directional guidance for active surface motility, providing new insights into microbial transport, retention, and resilience on submerged surfaces.

biophysics↗

bioRxiv2026

ARID1A deficiency unleashes centromeric RNA transcription to drive chromosomal instability and boosts PKMYT1 inhibitor efficacy via RNA sensing

Cancer gene-associated mutations and molecular hallmarks of chromosomal instability (CIN) are unexpectedly common in histologically normal cells and tissues. These emerging findings challenge the binary distinction between "normal" and "cancerous" cells and suggest that early tumorigenesis may commence against a background of widespread yet largely tolerated genomic instability. However, it remains largely unexplored how a cancer gene-associated mutation can initiate the development of CIN-like states in non-malignant cells and drive tumor evolution. ARID1A, a chromatin remodeling factor, was identified as the most frequently mutated gene in both gastric normal epithelium and tumors. This distinctive molecular convergence presents an opportunity to elucidate the mechanisms by which a cancer-associated gene facilitates the initiation of early CIN phenotypes and develop effective antitumor strategies. In the present study, using primary human gastric organoids, we employed optical genome mapping (OGM) and live-imaging technologies to demonstrate that ARID1A depletion induced a wide spectrum of structural variants (SVs), copy number variants (CNVs), and chromosomal segregation errors, characteristic features of CIN at a very early stage of gastric tumorigenesis. Mechanistically, ARID1A bound centromere repetitive satellite DNA (satDNA) sequences. Its SWI/SNF-associated chromatin remodeling activity was required for suppressing satDNA transcription and the production of -SatRNA, through restricting RNAPII elongation. Consequently, ARID1A depletion led to overexpression of -SatRNA, and a higher incidence of sister chromatid exchange (SCE), a sensitive indicator of CIN. Importantly, the elevated -SatRNA expression in ARID1A-deficient cells further established a dual therapeutic vulnerability for G2/M checkpoint blockade, such as PKMYT1 inhibitor (PKMYTi), by concurrently aggregating CIN-induced cell death and activating self-dsRNA sensing-mediated innate immune response. Notably, PKMYTi markedly promoted -SatRNA expression, aberrant release of these self-derived dsRNAs into the cytosol and a robust activation of the RIG/MDA5-MAVS-depenent type-I interferon response in ARID1A-depleted cells. As expected, PKMYTi potentiated the efficacy of immunotherapy in ARID1A-deficient gastric tumors. Together, our findings reveal that ARID1A deficiency unleashes centromeric -SatRNA transcription, which sets the molecular stage for tumor evolution and targeted therapy by coordinately inducing CIN and self-dsRNA-induced innate immune responses.

cancer biology↗

bioRxiv2026

Empagliflozin preserves cardiac function and modulates metabolism in a mouse model of Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is a fatal genetic disorder characterized by skeletal muscle degeneration and cardiomyopathy without a cure. This study examined the therapeutic potential of the sodium-glucose cotransporter 2 (SGLT2) inhibitor empagliflozin (EMPA) on cardiac function in the dystrophin-deficient mdx mouse model of DMD. Male mice were fed control chow or EMPA-containing chow ([~]25 mg/kg/day), and cardiac function was evaluated longitudinally by four-dimensional ultrasound imaging. EMPA did not alter left ventricular mass or chamber volume but preserved ejection fraction (EF) for 12 weeks, maintained significantly higher EF through 24 weeks, and attenuated global impairment of systolic and diastolic myocardial deformation. These functional improvements were accompanied by reduced cardiomyocyte hypertrophy and decreased expression of cardiac stress genes. EMPA reduced mitochondrial DNA damage, increased mitochondrial DNA copy number, and induced transcriptional signatures consistent with enhanced fatty acid and ketone metabolism, contributing to increased myocardial ATP content. Systemically, EMPA improved body mass trajectory, preserved relative lean mass, enhanced skeletal muscle torque, and did not adversely affect renal function. Together, these findings demonstrate that EMPA improves cardiac performance and mitochondrial integrity while enhancing myocardial energy availability in mdx mice, supporting SGLT2 inhibitors as a promising therapeutic strategy for individuals with DMD.

physiology↗

bioRxiv2026

Digital Twin Brain simulation and manipulation of a functional brain network underlying mental illness

Linking synaptic-level perturbations to distributed brain-network dynamics remains a central challenge for understanding and treating mental illness. Although recent whole-brain models can reproduce individual brain activity patterns, they largely function as descriptive simulators rather than mechanistic, intervention-capable systems. Here we present an intervention-capable digital twin of the human brain, integrating individual neuroanatomy and task-evoked dynamics within a neuronal-scale framework. Individualised digital twin brains recapitulate a participant-specific compact cortico-subcortical network phenotype that captures transdiagnostic psychopathology across population and clinical cohorts. In silico modulation of excitatory and inhibitory synaptic conductance produces bidirectional, heterogeneous network responses across individuals. Population-scale simulations stratify individuals and predict longitudinal symptom trajectories from DTB-derived response profiles. Independent pharmacological functional MRI data further validate the predicted baseline-dependent network responses in vivo. Together, these findings establish digital brain models as experimental platforms for mechanistic perturbation, behavioural prediction and stratification, providing a foundation for precision neuroscience and psychiatry.

neuroscience↗

bioRxiv2026

Vagus Nerve Stimulation Ameliorates Epilepsy via a Gut Microbiota-Butyrate-Vagus Nerve-Brain Axis

Vagus nerve stimulation (VNS) is an established therapy for drug-resistant epilepsy, yet its mechanism remains partially understood. Here, through an integrated clinical-translational approach, we demonstrate that VNS modulates the gut microbiome and alter the level of butyrate to reduce seizure susceptibility via vagus nerve-dependent signaling. In a longitudinal cohort of epilepsy patients, VNS enriched short-chain fatty acid-producing bacteria, including Akkermansia muciniphila, Prevotella, Alistipes, and Odoribacter. Among clinical responders, fecal butyrate levels decreased concomitantly with an increase in plasma butyrate concentrations. Fecal microbiota transplantation from post-VNS patients into mice reduced seizure severity and improved gut barrier integrity. In a murine model of epilepsy, VNS similarly increased the abundance of Akkermansia and plasma butyrate concentrations, decreased fecal butyrate levels, and abolished its antiseizure effects upon vagotomy. Either colonization with Akkermansia muciniphila or exogenous butyrate supplementation was sufficient to reduce seizures and anxiety-like behavior, effects that also required intact vagal signaling. Our findings define a microbiota-butyrate-vagal pathway essential for the therapeutic effects of VNS, highlighting the gut-brain axis as a target for epilepsy treatment. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/707138v1_ufig1.gif" ALT="Figure 1"> View larger version (75K): org.highwire.dtl.DTLVardef@8243e6org.highwire.dtl.DTLVardef@37f0e6org.highwire.dtl.DTLVardef@a8b321org.highwire.dtl.DTLVardef@1887342_HPS_FORMAT_FIGEXP M_FIG C_FIG HIGHLIGHTSO_LIVagus nerve stimulation (VNS) remodels the gut microbiota and alter the level of butyrate. C_LIO_LIVNS enriches short-chain fatty acids-producing bacteria, specifically Akkermansia muciniphila, in both humans and mice. C_LIO_LITransplantation of VNS-conditioned microbiota confers seizure protection and restores gut barrier integrity. C_LIO_LIAkkermansia muciniphila or exogenous butyrate is sufficient to reduce seizures via a vagus nerve-dependent pathway. C_LI

neuroscience↗

bioRxiv2026

Z-RNA-ZBP1 axis drives Tau-mediated neurodegeneration

Although the causes of Tau aggregates vary, once Tau aggregates are formed, their neurotoxicity significantly contributes to neuronal death and cognitive decline in tauopathies, with Alzheimers disease (AD) being the most well-known example. Despite its central pathogenic role, however, effective therapeutic strategies targeting neurotoxicity of Tau remain poor. Here we demonstrate the pathogenic role of neuronal cell death in Tau-related neurodegeneration. Tau-expressing neurons undergo cell death through Z-DNA-binding protein 1 (ZBP1) activation triggered by endogenous Z-RNAs. These Z-RNAs are derived from reactivated transposable elements (TEs) that are typically silenced within heterochromatin. Tau aggregates show a strong affinity for H3K9me3-modified chromatin, effectively sequestering these epigenetic marks from Heterochromatin Protein 1 (HP1), thereby disrupting the condensation of constitutive heterochromatin. Clinically, an inverse correlation between ZBP1 expression levels in excitatory neurons and cognitive performance in AD patients was observed. Importantly, Zbp1 haploinsufficiency significantly ameliorated cognitive deficits in aged Tau-transgenic mice (24-month-old), highlighting the therapeutic potential of ZBP1 inhibition to strive against neurodegeneration in tauopathies.

neuroscience↗

bioRxiv2026

Lethal permeabilization of host bacteria to small-molecule compounds during phage penetration

The tailed phages (Caudoviricetes) rely on specialized mechanisms to inject their double-stranded linear genomic DNA (gDNA) across the bacterial envelope. During this gDNA entry process, ionic fluxes and membrane depolarization may occur, potentially leading to increased vulnerability to antibiotic molecules. Here, we report that phage gDNA translocation combined with certain small molecules triggers a rapid and phage-specific cell permeabilization leading to growth arrest. Using live-cell fluorescence microscopy, we visualized the accumulation of otherwise excluded compounds such as anthracyclines and propidium iodide. We show that the influx and accumulation of these compounds depend on both the presence of an inner membrane (IM) receptor and persistent membrane depolarization. We further demonstrate that phage-induced permeabilization enhances the efficacy of certain antibiotics, enabling a synergistic elimination of antibiotic-resistant bacteria. Our results provide a mechanistic foundation for combining phages with small-molecule therapeutics and offer new insights into how phage entry relies on and alters host physiology.

microbiology↗

bioRxiv2026

The targeted cytosolic degradation of class I histone deacetylases is essential for efficient alphaherpesvirus replication

Viral infection triggers a robust DNA damage response (DDR), reshaping the host chromatin landscape to facilitate viral replication. Here, we uncover a novel mechanism by which alphaherpesviruses exploit the DDR pathway. We demonstrated that herpes simplex virus 1 (HSV-1) and pseudorabies virus (PRV) induced selective degradation of class I histone deacetylases (HDAC1/2), leading to histone hyperacetylation and subsequent DDR activation. Strikingly, viral infection promoted nuclear export of HDAC1/2, followed by MDM2-mediated K63-linked polyubiquitination and proteasomal degradation in the cytoplasm. Pharmacological inhibition of either DDR signaling or HDAC1/2 nuclear export significantly affected viral replication in vitro and in vivo. Our findings reveal a unique viral strategy to hijack host epigenetic regulation for efficient replication and identify potential therapeutic targets for alphaherpesvirus infections.

cell biology↗

bioRxiv2025

Mast cell extracellular granules are bioactive condensates driven by heparin and polyamine

Biomolecular condensates are membraneless bodies that organize biochemical reactions typically within cells. However, the roles of condensates in extracellular space--where conditions differ substantially from intracellular space--remain poorly understood. Here, we report mast cell extracellular granules (MCEGs), a stable membraneless entity, are condensates assembled via electrostatic interactions between glycosaminoglycans and polyamines. Disrupting polyamine synthesis or trafficking blocks MCEG formation and compromises the storage of proteases and cytokines. Granules reconstituted with heparin and spermine are sufficient to enrich mediators such as CPA3 and TNF, maintaining an elevated pH and higher concentrations of calcium and zinc compared to the extracellular milieu. This unique environment enhances CPA3 enzymatic activity. Furthermore, the granules increase TNF binding and its bioactivity toward endothelial cells. Together, we reveal MCEGs as functionally active biomolecular condensates with distinct biochemical and immunological properties; MCEGs are formed through sugar-metabolite interactions, expanding the mechanisms of condensate assembly beyond classical protein-protein and protein-RNA interactions.

cell biology↗

bioRxiv2025

Engineered Proteins Mimic ssRNA Phage to Disrupt Type IV Pili

Antimicrobial resistance is a growing global health crisis, with ESKAPE pathogens, such as Acinetobacter species, contributing significantly to hospital-acquired infections. These bacteria employ various virulence factors, including extracellular type IV pili (T4P), which serve as essential appendages for DNA uptake, biofilm formation, and resistance to antibiotics. Single-stranded RNA (ssRNA) bacteriophages (phages) exploit these retractile pili as entry receptors, but the exact mechanism of viral RNA delivery following pilus binding and retraction remains poorly understood. In this study, we investigated the entry mechanism of the ssRNA phage AP205 by identifying the specific phage components necessary for T4P detachment, a key step in viral genome entry. Our data reveals the phages maturation protein (Mat) is sufficient to induce pilus detachment on its own, and the overall virion structure further enhances the efficiency of this process. These findings provide mechanistic insights into how ssRNA phages exploit bacterial T4P as part of their infection pathway and suggest a conserved strategy for host entry. ImportanceAcinetobacter species are widespread environmental bacteria and members of the ESKAPE group of pathogens, often associated with hospital-acquired infections amongst immunocompromised patients. A major reason for the increase in antibiotic resistance in Acinetobacter species is its use of T4P to evade antibiotic treatment. With antibiotic resistance becoming a global health crisis, targeting these virulence factors represents a promising approach to combat infections. Since T4P are critical for Acinetobacter virulence, understanding mechanisms that can disrupt them is highly important. ssRNA phages provide a natural model for this, as they can target T4P to initiate infection. Recent research has shown that ssRNA phages can detach pili during their infection process. However, the precise mechanism behind this phenomenon remains unknown. Our research addresses part of this knowledge gap by identifying the key components required for this pilus detachment. This work will enhance the current understanding of the virulent T4P in Acinetobacter species, which could ultimately lead to broader medical advancements.

microbiology↗