Biology subjects

Zhang, F.

Publications and source records attributed to Zhang, F..

At least 73 records · Page 4Linked to original sources

bioRxiv2026

Transplanting ANXA1- CD8+ Naive T cells Delay Aging Through Senolysis

Immunosenescence is a hallmark of aging, yet strategies using defined immune subsets to counteract it are largely unexplored. We performed paired scRNA/TCR-seq on CD45 cells from human bone marrow (15 donors, 3-91 years). T cells were the most altered lineage, with CD8 naive T cell contraction and functional impairment. We identified an expanding ANXA1 CD8 naive subset with senescence signatures and impaired function. ANXA1-deficient CD8 T cells exhibited increased resting stemness and enhanced activation/cytotoxicity upon stimulation. ANXA1- cells showed senolytic activity in vitro and reduced senescence burden in vivo. Monthly transfer of syngeneic ANXA1- CD8 naive T cells into aged mice extended median lifespan by >30 weeks, improving cardiac function, bone density, motor coordination, and marrow immune microenvironment. Our study identifies ANXA1 as critical in CD8 naive T cell aging and establishes ANXA1- cell transfer as a strategy to counter immunosenescence and promote healthy aging.

immunology↗

bioRxiv2026

A Tissue Culture Free Genome Editing Strategy in Plants Using Broad-Host-Range Viral Vectors Derived from Geminiviruses

The use of viral vectors offers a promising alternative to traditional transformation methods for creating gene-edited plants. In this study, we developed a novel plant genome editing system by delivering Cas9, Cas12f, and Cas12j nucleases along with their guide RNAs using a broad-host-range geminivirus, Wheat dwarf India virus (WDIV), in combination with Ageratum yellow leaf curl betasatellite (AYLCB). Cas9, Cas12f, and Cas12j nucleases were efficiently expressed along with corresponding guide RNAs under viral promoters. By leveraging tRNA spacers in place of external promoters and terminators, we significantly reduced the overall cargo size, streamlining vector design. Additionally, we compared the traditional AtU6-driven gRNA delivery with a novel spacer:gRNA:spacer format in Cas9-expressing lines and observed comparable editing efficiencies. The broad host range of WDIV and AYLCB, combined with this tissue culture-free genome editing platform, opens up possibilities for editing across a wide range of plant species.

plant biology↗

bioRxiv2026

TCR signal strength determines Treg instability and discrimination of self versus non-self antigens

Regulatory T cells (Tregs) expressing autoreactive T-cell receptors (TCRs) maintain immune self-tolerance, yet their fate upon antigen encounter remains unclear. Although selected in the thymus for high-affinity self-recognition, the cross-reactive nature of the TCR repertoire allows some Tregs to also recognize foreign antigens with high affinity. Here, we identify cross-reactive destabilization, a process in which high-affinity recognition of foreign antigens erodes Treg stability and redirects lineage fate. Using a thymic-derived Treg (tTreg) TCR capable of recognizing both self and foreign antigens distinct from the self-ligand that mediated its thymic selection, we show that stimulation with high-affinity non-self agonists induces Foxp3 loss and conversion into effector-like ex-Tregs, whereas self-antigen stimulation preserves lineage stability. Treg instability also increases with age and correlates with activation, suggesting that cumulative foreign-antigen exposure drives this process. These findings reveal a signal-strength-dependent model in which strong TCR engagement induces cross-reactive destabilization to balance immune responsiveness and self-tolerance. One Sentence SummaryForeign antigen-driven destabilization of Treg cells balances immunity and tolerance

immunology↗

bioRxiv2026

Harnessing Tumor-Specific Transcript Diversity Uncovers a Shared Neoantigen Reservoir for Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is refractory to immunotherapy due to its immunologically cold microenvironment and the scarcity of mutation-derived neoantigens. Here, we introduce NeoAPP, a computational tool designed to systematically decode neoantigens arising from tumor-specific transcripts (TSTs) generated by transcriptional dysregulation. Multi-cohort transcriptomic profiling of 413 PDAC samples using NeoAPP reveal a median of 351 neoantigens per sample derived from 56 neoantigen-encoding TSTs (neoTSTs), surpassing mutation-derived counterparts in both abundance and patient coverage. Mechanistic analyses show that non-canonical splicing junction and transposable element activation drive neoantigen generation, while FOXA2-regulated promoter usage constitutes a potential major source of neoTSTs. Tumor-derived neoTSTs are also detected in extracellular vesicles and cancer-associated fibroblasts, implicating stromal crosstalk in immune modulation. Vaccination with neoTSTs induce CD8+ T cell responses in HLA-A*02:01/A*11:01 transgenic mice and suppressed tumor growth in syngeneic PDAC models. Collectively, this work establishes TST-derived neoantigens as a dominant and therapeutically actionable antigen reservoir in PDAC, advancing a transcriptome-guided framework for neoantigen discovery with potential to overcome immune resistance in low-mutation cancers. Abstract Figure O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=196 SRC="FIGDIR/small/705024v1_ufig1.gif" ALT="Figure 1"> View larger version (71K): org.highwire.dtl.DTLVardef@82ff31org.highwire.dtl.DTLVardef@401342org.highwire.dtl.DTLVardef@b0771corg.highwire.dtl.DTLVardef@15c03ef_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2026

Selective targeting of type II tRNAs underlies SLFN14-mediated translational repression and its dysregulation by thrombocytopenia-linked mutations

Schlafens (SLFNs) are interferon-inducible regulators of RNA metabolism and cell fate. SLFN14 is a ribosome-associated endoribonuclease whose pathogenic variants cause autosomal dominant inherited thrombocytopenia (IT), but the underlying disease mechanism has been unclear. We show that SLFN14 represses global protein synthesis through selective cleavage of type II tRNAs. IT-linked mutations alter RNA substrate specificity, enhancing degradation of type II tRNAs while reducing rRNA cleavage. This shift promotes ribosome stalling at codons decoded by type II tRNAs, triggering global translational arrest, stress signaling, and cell death. These findings define the molecular basis of SLFN14-associated thrombocytopenia and highlight selective tRNA targeting as a mechanism regulating translation and cell fate.

molecular biology↗

bioRxiv2026

Structural Mechanisms of SAMD9 Autoinhibition and Pathogenic Dysregulation

SAMD9 and SAMD9L (SAMD9/9L) are large cytosolic proteins essential for hematopoietic homeostasis and antiviral defense1-3. Germline gain-of-function (GoF) mutations in SAMD9/9L cause severe multisystem disorders and predisposition to leukemia, yet the mechanisms that regulate SAMD9/9L activity and how pathogenic mutations disrupt these processes, remain poorly understood. Here, we determine cryo-electron microscopy structures of human SAMD9 in multiple conformational and oligomeric states. We show that SAMD9 predominantly adopts a closed, autoinhibited conformation stabilized by a central ATP-bound nucleotide-binding oligomerization domain (NOD) and an extensive network of intramolecular interactions. Recurrent patient-derived GoF mutations localize to and destabilize these intramolecular interfaces, and restoring the disrupted interactions through compensatory mutations reinstates autoinhibition. We further identify low-abundance asymmetric SAMD9 dimers in which one protomer undergoes large conformational changes and establishes intermolecular interactions that are essential for SAMD9 activation. Together, these findings define the structural basis of SAMD9 autoinhibition and explain how human GoF mutations subvert this regulatory mechanism to drive disease.

biophysics↗

bioRxiv2026

Evolutionary genomics of local adaptation, climate vulnerability, and linarin metabolism in Opisthopappus longilobus

Global climate change and human activities are posing substantial threats to biodiversity. The genus Opisthopappus (O. taihangensis and O. longilobus), endemic to Chinas Taihang Mountains, possesses great ecological, ornamental and medicinal value. However, it is confronted with the pressures of habitat fragmentation and climate change. Here, we present the first haplotype-resolved, chromosome-scale genome assembly of O. longilobus ([~]2.95 Gb) and re-sequence 115 individuals across its range. Comparative analyses show Opisthopappus is sister to Artemisia-Chrysanthemum, with Opisthopappus and Chrysanthemum diverging at 5.15-5.18 million years ago. A profound genetic divergence is evident between O. taihangensis and O. longilobus, resulting in two distinct lineages within each species, driven by geography and climate. Our analyses indicate restricted gene flow, low diversity, and recurrent demographic bottlenecks collectively contribute to their endangerment. By integrating population genomics and environmental variables, we identified 4,437 core adaptive genes linked to water deprivation, and metabolism. Genomic offset predicts higher maladaptation risk in populations under drastic climate change. Furthermore, diverged promoters of two O-methyltransferase genes, OMT250 and OMT310, likely underlie the differential acacetin/linarin accumulation between C. morifolium and O. longilobus. These findings advance understanding of Opisthopappus evolution and climate vulnerability, offering a model for genomics-guided biodiversity conservation.

plant biology↗

bioRxiv2026

Exploring the GM-CSF Histidine Triad as a Modulator of Structure, Molecular Motion, and Ligand Binding

Granulocyte macrophage-colony stimulating factor (GM-CSF) is a cytokine that plays a role in immune modulation. Its expression is associated with a multitude of different effects ranging from harmful, as in diseases such as rheumatoid arthritis and multiple sclerosis, to beneficial, as in the case of mitigation of diabetes type I and neutropenia. However, there is a large gap in knowledge explaining how GM-CSF toggles its structure for such physiological and pathological interactions. Our work describes an ongoing attempt to address this gap by focusing on a clustered histidine triad within -helices near the N-terminus, which prior studies have suggested play a role in binding ligands at an acidic pH. While GM-CSF is known to be highly flexible at a more acidic pH, several properties of its histidine triad remain unclear at the physiological pH at which GM-CSF would encounter its binding partners. We describe an effort to characterize the role of the GM-CSF histidines under physiological pH, specifically to determine if these histidines are key to GM-CSF structural integrity, and whether individual histidine residues modulate binding as they do at a lower pH. Our findings reveal that, while the histidine residues have an impact on GM-CSF structure, flexibility, and stability, they alone do not modulate the affinity for ligands at neutral pH. These data provide an initial explanation for the pleiotropic functions and interactions of GM-CSF within a biophysical context. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=82 SRC="FIGDIR/small/700583v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@a6fffcorg.highwire.dtl.DTLVardef@1f00c30org.highwire.dtl.DTLVardef@b04c50org.highwire.dtl.DTLVardef@6224d9_HPS_FORMAT_FIGEXP M_FIG C_FIG

biophysics↗

bioRxiv2026

CAR-T-drug conjugate against solid tumor

Chimeric antigen receptor (CAR)-T cell therapy has been clinically successful in hematologic cancers but faces challenges in solid tumors, primarily due to limited tumor infiltration, immunosuppressive tumor microenvironments (TME), and antigen heterogeneity. While combining CAR-T cell therapy with chemotherapy can enhance antitumor activity, this often leads to substantial systemic toxicity. In this study, we introduce CAR-T-drug conjugate (CAR-T-D-C), a new class of dual-functional therapeutics that effectively addresses these obstacles by integrating click chemistry for precise conjugation of cytotoxic agents onto antigen-specific CAR-T cells. By transforming the hostile TME into an ally, this approach facilitates localized delivery of cytotoxic payload directly to the tumor site, enhancing the overall effectiveness of CAR-T therapy in solid tumors. CAR-T-D-Cs with different CAR-T cell binders exhibit robust antitumor activity across diverse solid tumor models, including both human tumor xenografts and syngeneic models. Spatial transcriptomic studies reveals that CAR-T-D-C achieves improved CAR-T tumor infiltration and functional activation within the TME. Compared to conventional CAR-T therapy, CAR-T-D-C markedly enhances immune cell infiltration, augments effector functions, promotes antigen spreading, amplifies systemic immune responses, and improves overall anti-tumor immunity. CAR-T-D-C represents a versatile therapeutic concept that combines the potency of small molecule drugs and the specificity of CAR-T cells as a 2-in-1 immunochemotherapy for treatment of solid tumors.

immunology↗

bioRxiv2025

Ensemble-DeepSets: an interpretable deep learning framework for single-cell resolution profiling of immunological aging

Immunosenescence increases susceptibility to infection and reduces vaccine responsiveness, yet bulk transcriptomic clocks obscure the cellular heterogeneity underlying this process. Here, we present IDEAL-Age, an interpretable deep learning framework that operates directly on single-cell PBMC transcriptomes. Benchmarking against 31 methods across independent cohorts demonstrates superior predictive performance. The frameworks interpretability uncovers linear and non-linear transcriptomic dynamics that reveal phase-specific physiological transitions, and identifies pro-youthful or pro-aging cellular contributions. Application to systemic lupus erythematosus (SLE) reveals accelerated immunological aging driven by interferon-associated monocyte shifts. IDEAL-Age establishes a high-resolution computational framework for deciphering systemic immune aging.

bioinformatics↗

bioRxiv2025

CryoDDM: CryoEM denoising diffusion model for heterogeneous conformational reconstruction

Heterogeneous protein reconstruction can reveal the relationship between protein dynamics and function, which represents one of the foremost challenges in cryogenic electron microscopy (cryo-EM) single-particle analysis (SPA). However, high-intensity noise results in inaccurate parameter estimation during classification and reconstruction, making it difficult to capture the subtle motions of proteins. Here, we present the Cryo-EM denoising diffusion model (CryoDDM), which denoises images while preserving high-frequency structural information, benefiting conformational heterogeneity classification and reconstruction. The image denoised by CryoDDM can be used to improve downstream analysis, enhance reconstruction resolution, discover new protein conformations, and map out conformational variations. Validated against tree diverse experimental datasets, spanning a proteasome, a membrane protein and a spike protein, our results consistently demonstrate the accuracy and superiority of CryoDDM. By guiding reconstruction with denoised images, CryoDDM enables high-resolution reconstruction of heterogeneous conformations, paving the way to illuminate fundamental questions in structural biology. The CryoDDM project are published at https://github.com/BIT-FuweiLi/CryoDDM.

bioinformatics↗

bioRxiv2025

Decoding Neoantigen-encoding Tumor-Specific Transcripts Unveils a Shared Target Reservoir for Immunotherapy in Hepatocellular Carcinoma

Background and AimsPrimary liver cancer, predominantly hepatocellular carcinoma (HCC), has limited therapeutic options. While mutation-derived neoantigen vaccine holds promise, its success is hindered by low antigen availability. This study explores transcriptome-derived neoantigens (neoantigen-encoding tumor-specific transcripts, neoTSTs) in HCC, characterizing their features, generation mechanisms, and therapeutic potential. Approach and ResultsWe analyzed RNA-seq data from 1,013 liver cancer patients and constructed a multi-layered reference dataset. Using a customized pipeline, we identified an average of 60 neoTSTs per patient, significantly surpassing mutation-derived neoantigens (neoMuts). NeoTSTs exhibited higher population frequencies, with 73.1% providing multiple epitopes, and were validated through mass spectrometry and HLA transgenic mouse models. Mechanistically, neoTSTs were generated via retained introns, transposable element activation, HNF4A-regulated alternative promoters, and de novo transmembrane domain (TMD) generation. Single-cell analysis revealed neoTSTs cover >75% of tumor cells and identified antigen-presenting cancer-associated fibroblasts (apCAFs) that enriched in immunotherapy responders and amplified CD4 T-cell responses via MHC-II presentation. In murine HCC models, neoTST vaccination outperformed neoMuts, inducing dual MHC-I/II activation and significant tumor growth inhibition. ConclusionsNeoTSTs represent a superior neoantigen source in HCC, compensating for the limitations of mutation-derived targets. Their abundance, sharedness, and dual MHC pathway activation highlight their potential for personalized immunotherapy, particularly in low-TMB tumors. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=178 SRC="FIGDIR/small/692877v1_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@1bedfedorg.highwire.dtl.DTLVardef@5f6c95org.highwire.dtl.DTLVardef@d1deb5org.highwire.dtl.DTLVardef@743e85_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2025

Causality-oriented regulatory inference and rational transcriptomic reprogramming design with CASCADE

Systematically elucidating the causal structure of gene expression regulation is the foundation for identifying key regulators of cellular function and designing rational interventions thereof. While advances in high-content perturbation screens enables experimental probing of causal regulatory effects, the massive genomic scale, measurement noise and confounding factors pose significant challenges for existing causal discovery and inference algorithms. Here, we present CASCADE, an end-to-end framework that integrates de novo causal discovery with prior regulatory knowledge for genome-wide causal discovery and inference. In addition to its superior performance on causal regulatory structure discovery and counterfactual inference for unseen perturbation effects, CASCADE enables, for the first time, causality-oriented rational intervention design for transcriptomic programming towards various targeted cells within a unified framework.

bioinformatics↗

bioRxiv2025

Bioengineered 3D hPSC-cholangiocyte ducts with physiological signals for biliary disease modelling

The progression of intrahepatic biliary diseases remains poorly understood, underscoring the urgent need to develop physiologically relevant human intrahepatic cholangiocyte disease models. Current approaches lack the complexity and throughput to capture how diverse biliary microenvironmental signals shape cholangiocyte behavior. To address this gap, we created a fully epithelialized and perfusible 3D bile duct from human pluripotent stem cell-derived cholangiocytes characterized by robust primary ciliation, apical-basal polarity and CFTR-mediated chloride conductance. Our results revealed physiologically relevant fluid flow and biliary stroma cells as essential components for sustaining cholangiocyte epithelial barrier integrity and ciliation. From here, we interrogated a broad spectrum of biliary signals to study bile acid toxicity and cytokine-driven injury, offering an unprecedented view into intrahepatic cholangiocyte stress responses and potential pathological mechanisms. By integrating physiologically relevant signals, fidelity and functional resolution, this platform provides the foundation needed to precisely decode pathogenic drivers and accelerate therapeutic development for devastating cholangiopathies. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=198 HEIGHT=200 SRC="FIGDIR/small/686855v1_ufig1.gif" ALT="Figure 1"> View larger version (59K): org.highwire.dtl.DTLVardef@11c1255org.highwire.dtl.DTLVardef@1f78d11org.highwire.dtl.DTLVardef@14e9398org.highwire.dtl.DTLVardef@1bc08d5_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2025

Time-Series RNA Sequencing Reveals Temperature-Specific and Temperature-Compensated Circadian Genes in Drosophila

Circadian rhythms align the physiology and behavior of living organisms with the 24-hour day. As a defining property of circadian rhythms, temperature compensation preserves the 24-hour rhythmic periodicity despite environmental temperature changes. While the molecular clockwork that drives genome-wide oscillations in gene expression is well characterized, how circadian gene expression contributes to the maintenance of rhythmic outputs under thermal variation and to produce temperature compensation remains uninvestigated. We profiled circadian gene expression in the ectothermic animal Drosophila melanogaster using time-series RNA-seq of head tissues under constant darkness at 18{degrees}C, 25{degrees}C, and 29{degrees}C. Locomotion assays confirmed that behavioral rhythms were temperature compensated under these conditions. Analyses of the time-series RNA-seq samples revealed hundreds of oscillating genes at each temperature, yet the majority were temperature specific. Only 14 genes, including the core clock components period (per) and vrille (vri), oscillated across all three constant darkness conditions at different temperatures. Even among these, the phase, amplitude, and expression levels of these oscillating genes often shifted with temperature. Thus, temperature-compensated oscillating genes are rare and largely confined to core clock genes, while most oscillating genes are temperature-specific. Our results suggested a potential architecture: a robust, temperature-compensated core set of oscillating genes, and a flexible, temperature-responsive output layer. The latter likely establishes temperature-specific oscillating gene expression programs that enable the animal to achieve temperature compensation at behavioral and physiological levels.

molecular biology↗

bioRxiv2025

NDR1/2 kinases regulate cell polarization and cell motility through Cdc42 GTPase and Pard3 signaling in mammalian cells

Controlling cell polarity and the directionality of cell motility is critical for effective cell migration during wound healing. NDR (nuclear dbf2-related) kinase pathways have roles in cell morphogenesis that are conserved from yeast to humans. Here, we reveal that knockdown of NDR1/2 kinases significantly alters cell size, shape, and the actin cytoskeleton, while reducing migration persistence and impairing cell polarization in wound healing assays. Mechanistically, we find that NDR1/2 kinases regulate the spatial and temporal dynamics of Cdc42 GTPase. Reduced NDR kinase levels increase Cdc42 GTPase activity and disrupt Pard3 subcellular location. NDR kinases phosphorylate Pard3 at Serine144, and overexpressing Pard3 can partially restore wound healing in NDR-depleted cells, an effect lost when Serine144 is mutated. Finally, we determine that NDR1 knockdown significantly impairs wound closure in human skin ex vivo wound healing assays, highlighting NDR kinase physiological importance. Collectively, this study demonstrates that NDR kinases modulate cell motility and polarization through the control of Pard3 and Cdc42 signaling in human fibroblasts.

cell biology↗

bioRxiv2025

Preoptic activation induces a torpor-like hypothermic and hypometabolic state that is cerebroprotective

Therapeutic hypothermia for stroke has been limited by shivering, increased metabolic demand, and poor patient tolerance. Engaging endogenous thermoregulatory circuits to lower body temperature may overcome these limitations and modulate metabolism, offering an integrated approach to cerebroprotection. Here, we show that chemogenetic activation of neurons in the preoptic area (POA) elicits a torpor-like state in mice, characterized by sustained hypothermia and hypometabolism. In an animal stroke model, this endogenous hypothermic state significantly reduced infarct volume and improved motor outcomes compared to controls, whereas maintaining normothermia attenuated these protective effects. To explore metabolic mechanisms contributing to this state, we performed untargeted metabolomic profiling 30 minutes after POA activation and identified coordinated shifts in nucleotide, phospholipid, and sphingolipid pathways. These rapid, temperature-dependent changes indicate a metabolically reprogrammed state that may enhance neuronal resilience during ischemic stress. Together, our findings suggest that POA-driven hypothermia confers cerebroprotection through specific metabolic adaptations with translational potential.

neuroscience↗

bioRxiv2025

FABP5 regulates ether lipid metabolism to ameliorate atopic dermatitis

Atopic dermatitis is an allergic skin disease associated with a profound reorganization of the epidermal lipidome. The effect of the altered lipidome on the skin-resident immune cells that drive disease is unclear. Previous reports identified Fatty acid binding protein 5 (FABP5) as a biomarker for atopic dermatitis, yet how FABP5 might contribute to disease pathogenesis is unknown. Here, we use a murine model of atopic dermatitis, to demonstrate that FABP5 is highly expressed in immune and epithelial cell lineages and that FABP5 protects against skin inflammation. Lipidomic analysis revealed that FABP5 deficiency broadly disrupts the systemic abundance of ether-linked lipids, a minor but important subset of glycerophospholipids. We show that these changes in ether lipid abundance are crucial for the proper regulation of platelet activating factor (PAF), a potent inflammatory ether lipid derivative. Concordantly, we observe elevated PAF in FABP5-deficient mice with dermatitis and that depletion of basophils, a major source of PAF, is sufficient to ameliorate disease in these animals. Altogether, our findings reveal a novel role for FABP5 in the control of allergic inflammation through the modulation of ether lipid and PAF metabolism.

immunology↗