Biology subjects

Zou, Z.

Publications and source records attributed to Zou, Z..

At least 19 recordsLinked to original sources

bioRxiv2026

FXR2 Promotes Autophagic Clearance of Sindbis Virus Capsid and Protects Against Viral Encephalitis

Autophagy protects neurons from viral infection by removing toxic viral components, but the host factors that recognize viral proteins and direct their clearance remain incompletely defined. Here, we identify fragile X mental retardation syndrome-related protein 2 (FXR2) as a mediator of protective autophagy during Sindbis virus (SINV) infection. Quantitative proteomic analysis of host proteins associated with SINV capsid identified FXR2, an RNA-binding protein linked to stress granules and protein homeostasis. Co-immunoprecipitation and immunofluorescence confirmed that FXR2 associates and colocalizes with viral capsid in infected cells. Loss of FXR2 increased capsid accumulation, reduced LC3 lipidation and autophagosome formation, and impaired p62 degradation following infection. Reconstitution of FXR2-deficient cells restored autophagy and promoted capsid clearance. Although FXR2 deficiency did not significantly increase viral replication, it enhanced virus-induced cell death, suggesting that FXR2 protects infected cells by limiting viral protein toxicity rather than by directly restricting virus production. Consistent with this model, both Fxr2-null and heterozygous mice exhibited increased mortality following neurotropic SINV challenge, and Fxr2-null mice developed greater neuronal degeneration, inflammation, and cell death despite viral titers comparable to those in wild-type animals. Together, these findings identify FXR2 as a previously unrecognized component of the antiviral autophagy pathway that promotes viral capsid clearance and protects neural tissue from infection-associated damage.

microbiology↗

bioRxiv2026

Distinct activation mechanisms underlie ligand efficacy at a GPCR

Ligands that bind to the same G protein-coupled receptor (GPCR) can produce widely different levels of signaling. These differences in efficacy are central to pharmacology, yet how a receptor sequence determines signaling level remains incompletely understood. Here we develop a deep mutational pharmacology approach to measure how each residue in the -opioid receptor (OR) shapes responses to 15 opioids, yielding ~400,000 measurements of variant effects on signaling and expression, including full concentration-response series for three agonists. Mutational effects on potency are strongest near the orthosteric pocket, whereas effects on efficacy extend through the transmembrane core and intracellular face. Ligands share many functional determinants, but sensitivity to mutation differs with efficacy. As efficacy decreases, the residues required for signaling shift from the binding pocket towards the intracellular face; partial agonists therefore depend on residues that are dispensable for full agonists. Mutations can broadly increase receptor responses, allowing antagonists such as naloxone to produce signaling comparable to a full agonist and increasing the efficacy of partial agonist ligands. Combined mutations can also reorder the relative efficacies of ligands, showing that sequence changes reshape pharmacological differences rather than simply increasing or decreasing all responses together. These findings support a model in which ligands of different efficacy activate the receptor through distinct allosteric mechanisms which are determined by residues distributed across the receptor. Mapping these contributions across diverse ligands with deep mutational pharmacology provides a way to understand how one receptor converts molecular recognition into a range of signaling outputs.

biophysics↗

bioRxiv2026

NexuST: A Hierarchical Foundation Model for Spatial Transcriptomics

Spatial transcriptomics captures molecular states within cells and their organisation in tissue. However, integrating fine-grained gene information with spatial context at scale remains challenging for existing foundation models. Here we present NexuST, a hierarchical foundation model that repeatedly interleaves gene-level molecular modelling with cell-level spatial modelling, allowing the two levels to refine one another during end-to-end pretraining. For pretraining, we curated HumanST-46M, comprising 45.7 million human cells from 72 datasets across 11 organs and three imaging-based platforms. Across four held-out datasets totalling approximately 2.6 million cells, NexuST achieved state-of-the-art or competitive performance in cell-type annotation, region prediction, gene recovery and neighbourhood-composition prediction. We find that cell-intrinsic expression remains informative even for spatial tasks, as shown by an expression-only PCA baseline, while NexuST shows particularly strong gains where spatial context is essential. Overall, NexuST establishes a hierarchical framework that can serve as a general backbone for future spatial transcriptomics foundation models.

bioinformatics↗

bioRxiv2026

CDKL5 deficiency impairs TBK1-mediated autophagy and clearance of neuronal protein aggregates

The clearance of unwanted protein aggregates is essential for maintaining proteostasis and cellular function, particularly in long-lived cells such as neurons, yet the signaling pathways that activate selective autophagy of protein aggregates remain incompletely understood. Here, we identify the neurodevelopmental kinase CDKL5 as an upstream regulator of a signaling pathway involving the TBK1 adaptor SINTBAD and the selective autophagy receptors p62 and TAX1BP1. CDKL5-deficient mice show age-dependent accumulation of detergent-insoluble protein aggregates in the brain, accompanied by impaired TAX1BP1 recruitment and reduced p62 Ser405 phosphorylation. In cultured cells and primary cortical neurons, loss of CDKL5 delays clearance of puromycin- and proteasome-inhibitor-induced aggregates in a manner dependent on CDKL5 kinase activity. Mechanistically, CDKL5 kinase activity is required for SINTBAD Ser504 phosphorylation, a SINTBAD modification that promotes TBK1 activation, resulting in p62 Ser403/405 phosphorylation and TAX1BP1-dependent aggregate clearance. Phosphomimetic SINTBAD rescues these responses in CDKL5-deficient cells. These findings define a CDKL5/SINTBAD/TBK1 signaling axis that couples proteotoxic stress to activation of selective autophagy receptors and identify impaired proteostasis as a previously unrecognized consequence of CDKL5 deficiency.

physiology↗

bioRxiv2026

Age-driven Dysregulation of murine Dendritic Cells is controlled by cell-intrinsic and extrinsic effects

Aging is associated with chronic, low-grade inflammation and progressive immune dysfunction. However, the current understanding of age-associated changes in dendritic cells across tissues is scarce. Studies exploring ageing-associated changes in dendritic cells (DCs) have reported either a general decline in the overall DC compartment or subset-specific alterations affecting cDC1, cDC2, and pDC populations across spleen, lung and liver, underscoring the considerable inconsistencies across tissues and studies. To underpin whether age-associated changes are extrinsic or intrinsic we investigated DCs across bone marrow, six peripheral tissues and in in vitro bone marrow derived DC cultures to examine the effects of aging on DC-poiesis, tissue distribution, and cellular states related to DC functionality and activation. We discovered that aging selectively alters DC development in the bone marrow by reducing cDC progenitor populations while preserving pDC-poiesis. In peripheral tissues, however, age-associated changes in DC homeostasis were strongly tissue-dependent. The most significant shifts in cDC1 and cDC2 frequencies occurred in barrier tissues, such as the lung and small intestine. In contrast, the spleen and liver exhibited more limited or variable changes. These quantitative alterations were accompanied by tissue-specific changes in phenotypic and activation-associated markers, including CD24, CD103, CD11b, MHCII, and CD86. Single-cell transcriptomic analyses of senescent p21-expressing DC across tissues and subsets indicated localized inflammatory states that aligned with local macrophage populations, pointing toward cell-extrinsic niches that contribute to local age-associated dysfunction. Notably, aged bone marrow retained the capacity to efficiently generate DCs in in vitro Flt3L cultures, and antigen-presenting function of BMDC to CD4 and CD8 T cells was maintained, pointing towards preserved cell-intrinsic functions, albeit subset-specific differences in activation and inhibitory receptor expression in response to different pattern-recognition receptor agonists. Collectively, our findings indicate that aging does not superimpose a uniform alteration module to the DC compartment across tissues, but instead promotes selective alterations in DC ontogeny and tissue-specific remodeling of DC phenotypes and cellular states.

immunology↗

bioRxiv2026

S-Adenosyl-D-methionine as a Non-Physiological Substrate for a Wide Range of SAM-Dependent Enzymes

The ability of SAM-dependent enzymes to accept S-adenosyl-D-methionine [D-SAM, (SS,RC)-SAM] instead of the native cofactor S-adenosyl-L-methionine [L-SAM, (SS,SC)-SAM] remains largely unexplored. Challenging the stereochemical preference of SAM-dependent enzymes, we investigated the ability of different enzyme classes to accept D-SAM. Contrary to common assumptions, the tested N- and O-methyl transferases (MTs), as well as one of the examined C-MTs accepted D-SAM. Docking studies suggest that acceptance of D-SAM by C-MTs may be influenced by the angle between the transferable methyl group of SAM and the nucleophilic carbon of the substrate, along with enzyme and substrate flexibility. In addition to conventional MTs, the radical SAM glutamine C-MT QCMT showed low but detectable methylation activity with D-SAM. Furthermore, the azetidine-2-carboxylic acid synthase AzeJ not only uses D-SAM but also incorporates the stereocentre of D-methionine into the cyclic amino acid product. The pyridoxal 5'-phosphate (PLP)-dependent enzyme 1-aminocyclopropyl-1-carboxylic acid synthase (ACCS) also showed detectable turnover with D-SAM. These findings broaden the understanding of enzyme stereoselectivity, provide an overview of D-SAM-utilising enzymes, and identify first enzyme systems that may serve as starting points for engineering efforts aimed at shifting cofactor preference towards D-SAM.

biochemistry↗

bioRxiv2026

Vitamin D3 attenuates nitrogen mustard-induced dermal toxicity by enhancing microbial butyrate production via the intestinal VDR-α-defensin signaling pathway

Nitrogen mustard (NM)-caused severe cutaneous damage lacks effective targeted therapies. Vitamin D3 (VD3) shows promise as a therapy for NM-induced dermal toxicity; however, the underlying mechanisms remain elusive. Herein, we initially confirmed that NM induced gut flora dysbiosis, characterized by a decrease of Akkermansia muciniphila (AKK) abundance, thereby leading to butyrate reduction. Antibiotics (ABX) significantly promoted NM-induced skin injury, whereas fecal microbiota transplantation of the controls feces (HC-FMT) or AKK administration attenuated NM-induced dermal toxicity. HC-FMT or AKK significantly increased butyrate levels in feces and serum of NM-treated mice. Butyrate notably attenuated ABX-caused acceleration of NM-induced skin injury. Meanwhile, NM markedly decreased the expression of -defensins, MMP7, and VDR. NM failed to further decrease AKK abundance and BA contents in intestinal MMP7-deficient mice, which was abolished by human alpha defensin 5 (HD5) overexpression. And intestinal MMP7 deficiency enhanced NM-caused skin injury, which was markedly attenuated by HD5 overexpression, AKK transplantation, or BA supplementation. Moreover, NM also failed to further reduce MMP7 and -defensin expression, AKK abundance, and butyrate levels in intestinal VDR-silenced mice. Finally, VD3 remodeled the gut microbiome particularly enriching AKK, increased butyrate contents and promoted the expression of -defensins, MMP7, and VDR, thereby attenuating NM-induced skin damage. The protective effect of VD3 against NM-caused dermal toxicity was abolished by either ABX or intestinal-specific knockdown of MMP7 or VDR in mice; however, this impairment was reversed by butyrate or AKK. In conclusion, VD3 attenuated NM-caused dermal toxicity by promoting BA production via remodeling the gut microbiota, and this effect was partially mediated by the intestinal VDR--defensin signaling pathway. These highlight that targeting the gut flora or supplementing with BA could be potential therapies for NM-induced dermal toxicity.

molecular biology↗

bioRxiv2026

Macrophage Iron Metabolism in Allografts and Tumors

Macrophages are present at high frequencies in transplanted organs and solid tumors. These infiltrating macrophages are highly tuned by tissue niche signals. However, the underlying mechanisms that orchestrate the activation of distinct macrophage populations remain unclear. Here, using heart transplantation and tumor implantation models, we found that macrophages in cardiac allografts exhibited higher intracellular iron (Fe2+) level and higher expression of the iron transporter SLC11A1 than those in the solid tumors. In mice, the myeloid-specific deletion of Slc11a1 alleviated the proinflammatory state of macrophages and cardiac allografts rejection. Together, our findings identify SLC11A1 as a new player in immune response regulation, implicating SLC11A1 as a therapeutic target for both allograft and tumor rejection. This preprint reports initial findings; additional experiments are ongoing and will be included in a future full manuscript.

immunology↗

bioRxiv2026

Asymmetric Division in a Two-Cell-Like State Rejuvenates Embryonic Stem Cells

A fundamental question in biology is whether cellular aging is inevitable. Embryonic stem cells (ESCs) challenge this paradigm as rare normal cells capable of indefinite in vitro passage. However, the mechanisms underlying ESC lineage immortality remain unresolved. Using long-term live-cell imaging to follow fates of single ESCs, we show here that ESC lineage renewal is achieved through sporadic entry into a state characterized by the expression of two-cell embryo-specific markers. During this state, cells undergo asymmetric divisions, segregating accumulated DNA damage into one daughter lineage destined for elimination, while producing a second lineage that reverts to the pluripotent state. Importantly, the latter lineage exhibits signs of rejuvenation, including reduced DNA damage and enhanced chimeric efficiency. These findings underscore the crucial role of asymmetric cell division in maintaining the long-term health of the ESC lineage against mounting damage within individual cells, a potential model for studying cellular aging and rejuvenation in mammalian cells.

cell biology↗

bioRxiv2026

A Unified and Interpretable Framework for Evaluating Fluorescence Trace Quality in Transcription Kinetics

Quantifying transcriptional dynamics from fluorescence traces is a powerful approach to understanding gene regulation, but such analysis critically depends on the quality of the fluorescence signal. Experimental researchers often lack an objective and computationally simple way to assess trace quality before kinetic modeling. In this study, we fill in this gap via systematically investigating two key factors (i.e., signal-to-noise ratio (SNR) and trace length) using synthetic data generated from a composite-state Hidden Markov Model (cpHMM) simulator. By analyzing thousands of simulated traces, we identified quantitative thresholds (SNR [≥] 30 dB and length [≥] 360) beyond which transcriptional dynamics can be reliably captured for kinetic inference. Building on these findings, we further discovered a unified and easily computable quality indicator based on the difference between the first two autocorrelation lags. A threshold value of approximately 0.07 effectively separates reliable from low quality traces, providing a simple yet robust criterion for data selection. Together, these results establish a practical framework for assessing fluorescence trace reliability, offering experimental researchers an interpretable and computationally efficient tool to ensure data quality prior to transcription kinetics modeling.

bioinformatics↗

bioRxiv2025

Metabolic cross-talk promotes persistence of Enterococcus in a model of polymicrobial catheter-associated urinary tract infection

Catheter-associated urinary tract infections (CAUTI) account for 70%[~]80% of urinary tract infections (UTI) and can lead to adverse outcomes. Most CAUTIs are polymicrobial with resilient communities maintaining a consistent composition of species over time, despite antibiotic treatment and catheter replacement. However, the mechanisms promoting persistence are poorly understood. Here we examine how a chemical interaction between Gram-positive Enterococcus faecalis and Gram-negative Klebsiella pneumoniae can explain their high rate of co-occurrence on long-term indwelling urinary catheters. Sequence analyses of longitudinal isolates from several human patients co-infected with E. faecalis and K. pneumoniae revealed that despite frequent replacement, catheters became re-colonized with the same or a nearly identical consortium of strains throughout the study collection period. Using artificial urine medium (AUM), monoculture revealed that the K. pneumoniae isolates grew robustly and formed biofilm, while the E. faecalis isolates grew poorly and did not form biofilm. However, co-culture of paired isolates resulted in enhanced E. faecalis growth and biofilm, which could be reproduced by supplementing E. faecalis with cell-free K. pneumoniae conditioned AUM supernatant (KpAUMSup). Analyses using comparative transcriptomics, mutant strains and chemical inhibitors with cell culture and murine CAUTI models revealed that: i) KpAUMSup, but not AUM, stimulated expression of the E. faecalis Fsr quorum-sensing system; ii) Fsr was required for E. faecalis to respond to KpAUMSup; iii) E. faecalis cultured in KpAUMSup was more efficient in initiating CAUTI; and iv) Disruption of Fsr inhibited initiation of CAUTI. This interspecies signaling may help explain the high rate of co-colonization of these CAUTI pathogens and highlights new therapeutic strategies to treat polymicrobial CAUTI.

microbiology↗

bioRxiv2025

Uncertainty-aware transcription factor activity and perturbation inference without additional training

Understanding how transcription factors (TFs) control gene expression is essential for deciphering cellular regulatory programs. However, estimating TF activity remains challenging. Current methods rely on either broad TF-target databases, which increase false positives, or on curated sets with limited coverage. Most methods lack uncertainty quantification. Here, we introduce TFActProfiler, an integrated resource and computational framework that learns signed TF-mRNA effects by pretraining on prior TF-mRNA interaction knowledge and large RNA-seq atlases. Given an expression profile as input, TFActProfiler infers per-sample TF activity together with a confidence score that quantifies agreement between predicted and observed mRNA levels. Across TF knockdown datasets spanning multiple human cell types, TFActProfiler consistently improves TF activity inference over approaches based on unfiltered priors or narrowly curated target sets while retaining broad TF and mRNA coverage. The learned effect map further enables training-free prediction of transcriptome responses to TF perturbations. By coupling TF activity inference with training-free perturbation modeling and confidence estimates, TFActProfiler offers a tool for dissecting regulatory programs across diverse cellular states.

bioinformatics↗

bioRxiv2025

Programming Microbe-Computer Interaction for Customized Life-Nonlife and Cross-Life Communication

This extension of human-computer interaction (HCI) paradigm to the non-intelligent microbe-computer interaction (MCI) is attractive for building generalized life-nonlife communication. Main challenges lie in how to construct biohybrid interface within individual MCI unit and thereafter program cross-life communication based on these MCI units. Here, we propose the design and construction of opto-interfaced MCI unit composed of engineered microbes and computer terminals, for enabling quantifiable transduction between microbial signals and digital signals. These units were able to serve as biohybrid sensors, actuators and transceivers, supporting biomonitoring, bio-actuation and microbe-centric bidirectional operations. Based on these functional units, we established programmable cross-life communication architectures capable of unicast, multicast, and logic-gate-driven communication with temporal dynamic control. The architectures were validated in biomedical scenarios including tumor hypoxia biomarking, epidermal heavy metal detoxification, and colitis intervention, demonstrating robust performance in closed-loop diagnostic-therapeutic applications. Additionally, we integrated MCI with an unmanned surface vessel for environmental monitoring, highlighting its cross-domain potential. Collectively, we provide a scalable strategy for building customized life-nonlife and cross-life communication, which is expected as an important complement to internet of things (IoT).

synthetic biology↗

bioRxiv2025

The heterochronic activation of TGF-β signaling drives the diversity of the avian sterna

Adaptive evolution has driven the diversification of vertebrate skeletal morphology, enabling a wide array of locomotor modes and lifestyles. In volant birds (carinates), the sternum develops a ventral keel that provides an attachment site for massive pectoral muscles essential for powered flight. In contrast, flightless ratites have lost both flight capability and the keel, resulting in a striking morphological contrast between their sterna. Here, we interrogated the cellular and molecular basis underlying this morphological divergence by using chicken embryos as a carinate model and emu embryos as a ratite model. Through a series of analyses including spatiotemporal transcriptomics and a spheroid culture system, we found that TGF-{beta} signaling, which promotes proliferation of ventral sternal chondroprogenitors, is activated in both species until the stage when the left and right sternal progenitors meet; however, in chicken this activation persists beyond this stage, driving ventral extension of the keel primordium, whereas in emu it shuts off early, culminating in the absence of a protruding keel. Together, our findings suggest that skeletal morphological changes associated with behavioral transitions can arise from heterochrony in developmental signaling, thereby deepening our understanding of the evolutionary logic shaping skeletal diversification.

developmental biology↗

bioRxiv2025

Overcoming breeding constraints in polyploid oat from evolutionary insights

Polyploidy provides adaptive advantages in plants by buffering deleterious mutations1,2. While polyploidization can enhance agronomic traits such as increased biomass, known as the gigas effect1-4, increasing genetic gain in polyploid crops remains a critical but difficult goal due to the difficulty in dissecting complex trait inheritance5,6. Here we present chromosome-scale genome assemblies for 26 Avena taxa, spanning diploid, tetraploid, and hexaploid lineages. We traced four independent polyploidization events across the genus, including the formation of A. agadiriana as an allotetraploid (AgAgAg'Ag'), and revealed a reticulate evolutionary history shaped by gene flow involving four subgenomes (A, B, C, D), for example, the hybrid speciation of A. hirtula. Transcriptomic analysis of 286 samples across 11 tissues, combined with deleterious mutation analysis from a cultivated population of 112 accessions, showed that polyploidization led to widespread functional redundancy among homoeologs, supporting a genome-wide buffering effect. However, derived allele frequency analysis revealed that, while disrupting functional genes may yield desirable traits, the buffering effect impedes the fixation of beneficial loss-of-function mutations and thereby limits breeding efficiency. Based on these integrative analyses, we propose breeding strategies to circumvent these limitations by targeting beneficial loss-of-function alleles within the complex polyploid background of oat. Our study highlights broader challenges in the improvement of polyploid crops and provides a foundation for future breeding strategies.

evolutionary biology↗

bioRxiv2025

5-azacytosine induces cytotoxicity via 5-methylcytosine depletion on chromatin-associated RNA in leukemia

5-azacytidine (5-azaC) is a DNA hypomethylating agent clinically used to improve outcomes in myeloid malignancies. However, 5-azaC treatment causes gene dysregulation inconsistent with DNA hypomethylation changes, suggesting alternative mechanisms of action by 5-azaC. As a ribonucleoside analogue, 5-azaC is more readily incorporated into nascent RNA. Here, we demonstrate that RNA 5-methylcytosine (m5C) depletion by 5-azaC treatment, particularly at early time points, is sufficient to induce leukemia cell death. In contrast to its DNA demethylation function, the RNA-dependent effect of 5-azaC causes transcriptional repression, disrupting genes involved in cell cycle regulation and DNA repair. Mechanistically, 5-azaC impairs two specific m5C-mediated transcriptional regulatory pathways. First, depletion of m5C in chromatin-associated RNA (caRNA) disrupts the MBD6-mediated H2AK119ub deubiquitination. In parallel, this also impairs SRSF2 recruitment and the downstream H3K27ac deposition by p300. Indeed, loss of the caRNA methyltransferase NSUN2 caused prolonged cell cycle, defective DNA repair, and shifted hematopoietic lineage commitment toward erythropoiesis, mirroring the effects of 5-azaC treatment. Furthermore, we performed a leukemia cell line screen and identified that TET2 and IKZF1 depletion can sensitize 5-azaC treatment, consistent with the observed RNA-dependent cytotoxicity of 5-azaC in leukemic cells. In summary, our findings highlight the transcription repression by 5-azaC through depleting caRNA m5C, providing additional insights into the mechanism of action for 5-azaC, the prediction of its efficacy, and future directions for therapy developments based on 5-azaC. HIGHLIGHTO_LIRNA-dependent effects of 5-azaC are sufficient to drive leukemia cell cytotoxicity through transcriptional repression. C_LIO_LI5-azaC-induced caRNA m5C depletion impairs MBD6 binding and H2AK119ub deubiquitination. C_LIO_LI5-azaC-induced caRNA m5C depletion disrupts SRSF2 chromatin-binding, impeding p300 recruitment and H3K27ac deposition. C_LIO_LITET2 or IKZF1 depletion synergizes leukemia sensitivity to 5-azaC C_LI

molecular biology↗

bioRxiv2025

Nuclear 2'-O-methylation regulates RNA splicing through its binding protein FUBP1

2'-O-methylation (Nm) is an abundant RNA modification exists on different mammalian RNA species. However, potential Nm recognition by proteins has not been extensively explored. Here, we employed RNA affinity purification followed by mass spectrometry to identify Nm-binding proteins. The candidates exhibit enriched binding at known Nm sites. Interestingly, some candidates display nuclear localization and functions. We focused on the splicing factor FUBP1. Electrophoretic mobility shift assay (EMSA) validated preference of FUBP1 to Nm-modified RNA. As FUBP1 predominantly binds intronic regions, we profiled Nm sites in chromatin-associated RNA (caRNA) and found Nm enrichment within introns. Depletion of Nm led to increased exon skipping, suggesting Nm-dependent splicing regulation. The caRNA Nm sites overlap with FUBP1 binding sites, and Nm depletion reduced FUBP1 occupancy on modified regions. Furthermore, FUBP1 depletion induced exon skipping in Nm-modified genes, supporting its role in mediating Nm-dependent splicing regulation. Overall, our findings identify FUBP1 as an Nm-binding protein and uncover previously unrecognized nuclear functions for RNA Nm modification.

molecular biology↗

bioRxiv2025

Integrative Single-Cell RNA and ATAC Sequencing Reveals the Impact of Chronic Cigarette Smoking on Lung Epithelial Responses to Influenza and Hyperoxia

Cigarette smoke (CS) is a significant risk factor for developing acute respiratory distress syndrome (ARDS), but the cellular and molecular mechanisms linking smoking to ARDS susceptibility remain unclear. Our goal was to improve our understanding of these mechanisms. To address this, we established a mouse model comparing long-term CS exposure to non-smoking controls, examining responses to influenza infection and hyperoxia-induced lung injury. The mice were divided into six groups (n=1 per group): control (CON), cigarette smoke (CS), hyperoxia (HYP), influenza infection (FLU), cigarette smoke plus hyperoxia (CS+HYP), and cigarette smoke plus influenza infection (CS+FLU). Single-cell RNA sequencing (scRNA-seq) and single-cell ATAC sequencing (scATAC-seq) were performed on lung tissues. Quality control analysis using Seurat (v5.1.0) and Signac (v1.13.1) retained 78,402 cells from scRNA-seq and 84,144 cells from scATAC-seq, with 32,305 matched cells identified across both datasets. Differential gene expression analysis revealed significant smoking-associated alterations in cellular responses to influenza infection and hyperoxia exposure. Pathway enrichment indicated heightened immune responses, inflammatory signaling, and cellular survival pathways in smoking-exposed animals. Integration of scRNA-seq and scATAC-seq identified key transcription factors (TFs), including those involved in immune regulation, tissue repair, and chromatin remodeling mediating these responses. Overall, this study underscores the role of chronic cigarette smoke exposure in exacerbating pathways critical to ARDS pathogenesis, providing potential targets for therapeutic intervention.

bioinformatics↗