Biology subjects

Zhang, H.

Publications and source records attributed to Zhang, H..

At least 55 records · Page 3Linked to original sources

bioRxiv2026

Spatial transcriptomics reveals selective vulnerability of cardiac neural crest-derived glial cells in human myocardial infarction

Cardiac neural crest-derived glial cells (CNGs) are recently identified glial cells that support cardiac autonomic innervation and maintain sympathetic-parasympathetic balance. Their fate in myocardial infarction (MI) is unknown. Here, we analyzed 16 human cardiac spatial transcriptomes spanning normal myocardium (n=4), infarct zone (n=5), border zone (inner, n=1; outer, n=3), and remote zone (n=3). CNGs (S100B+/GFAP+, CD68- spots) were selectively lost along a spatial gradient from healthy tissue to the infarct core (Spearman rho = -0.92, p = 4.5 x 10-7). Tissue-area-corrected analysis confirmed that CNG loss (26% retained in infarct zone vs. normal; p = 0.016) vastly exceeded overall tissue loss, indicating selective vulnerability rather than bulk tissue destruction. Mechanistically, oxidative phosphorylation (OXPHOS) activity in CNG-positive spots correlated positively with CNG survival (partial rho = 0.65, p = 0.009 after controlling for spot composition), consistent with a high metabolic demand underlying their ischemic sensitivity. Pyroptosis - but not ferroptosis or apoptosis - signatures correlated with CNG loss (partial rho = -0.67, p = 0.006). These findings identify CNGs as selectively vulnerable cellular components of the cardiac autonomic system in MI and nominate metabolic failure and pyroptosis as candidate mechanisms, providing a spatially resolved foundation for future mechanistic and interventional studies.

bioinformatics↗

bioRxiv2026

Regulatory-scale stripe analysis from single-cell Hi-C with scStripe

Chromatin stripes are a directional architectural feature of three-dimensional genome organization, but their analysis in single-cell Hi-C (scHi-C) at regulatory resolution is hindered by extreme sparsity. We developed scStripe, an imputation-free two-stage statistical framework that detects stripes from sparse cell-type--aggregated scHi-C maps and directly quantifies the resulting aggregate-defined stripes in raw individual-cell contact maps using per-cell stripe scores. Across three complementary benchmark settings, scStripe achieved the highest F1 scores and showed strong aggregate stripe enrichment, while the detected stripes recapitulated characteristic structural and regulatory features reported in bulk data. Per-cell stripe scores resolved recurrent configurations of the EBF1-anchored stripe, captured genome-wide variation associated with cell type, cell-cycle phase, and developmental stage, and identified positively associated gene--stripe pairs with pronounced cell-type specificity using matched scRNA-seq. Together, scStripe provides a practical, scalable framework for regulatory-scale stripe analysis across single cells without requiring single-cell enhancement or 3D reconstruction.

genetics↗

bioRxiv2026

Loss of 20-HETE-GPR75 Signaling Impairs Renal Hemodynamic Adaptation in Sepsis

BACKGROUD: Sepsis is a life-threatening condition characterized by a dysregulated host response to infection. It frequently precipitates sepsis-associated acute kidney injury (SA-AKI). 20-Hydroxyeicosatetraenoic acid (20-HETE), is an important regulator of vascular tone. We aim to investigate whether disruption of 20-HETE signaling contributes to septic renal dysfunction. METHODS: In the animal study, Sprague-Dawley rats underwent the cecal ligation and puncture to induce sepsis and SA-AKI. Comprehensive cardiac and renal ultrasonographic assessments were performed in all animals. Blood samples were collected for biochemical assessment of renal function and quantification of circulating 20-HETE levels. Kidney tissues were harvested for analysis of the 20-HETE-GPR75-PLC/PKC signaling pathway and histological evaluation by hematoxylin and eosin staining. In the clinical study, circulating 20-HETE levels and renal hemodynamic parameters derived from point-of-care ultrasound were evaluated in healthy individuals and patients with sepsis. Venous blood samples were collected for quantification of serum 20-HETE concentrations. RESULTS: Firstly, CLP-induced septic rats produced a biphasic hemodynamic response, with early compensation followed by late cardiovascular decompensation, accompanied by progressive renal dysfunction, tubular injury, depletion of circulating and renal 20-HETE, and reduced renal GPR75 expression. Secondly, Restoration of 20-HETE signaling with a pharmacological analog improved systemic and renal hemodynamics, increased MAP, reduced serum creatinine, blood urea nitrogen, and ameliorated renal pathological injury. These protective effects were partially attenuated by PKC inhibition, implicating PKC-dependent signaling in 20-HETE-mediated renal protection. Moreover, in septic patients, circulating 20-HETE concentrations were reduced compared with healthy individuals and were lowest among those with SA-AKI, paralleling alterations in renal hemodynamic parameters measured by point-of-care ultrasound. CONCLUSIONS: Sepsis-associated depletion of 20-HETE accompanies impaired systemic and renal hemodynamic regulation and is associated with the development of SA-AKI. Restoration of 20-HETE signaling improves hemodynamic function and attenuates renal injury, potentially involving GPR75-associated PLC/PKC signaling. KEY WORDS: sepsis-associated acute kidney injury, 20-hydroxyeicosatetraenoic acid, GPR75, renal hemodynamics, point-of-care ultrasonography

pathology↗

bioRxiv2026

Substrate recognition and ion coupling mechanism of the human VIAAT

Inhibitory neurotransmission, essential for neural circuit homeostasis and proper neurological function, depends on the efficient sequestration of {gamma}-aminobutyric acid (GABA) and glycine into synaptic vesicles. This critical process is mediated exclusively by the vesicular inhibitory amino acid transporter (VIAAT). Despite extensive biochemical and physiological investigation, the molecular mechanism governing VIAAT-mediated transport has remained incompletely understood. Here, we determined structures of human VIAAT in multiple functional states, including apo, GABA-bound, and glycine-bound states, as well as apo state in chloride-free condition. VIAAT adopts a classical LeuT-fold and we elucidated how its large, electronegative binding pocket accommodates both GABA and glycine. Moreover, we resolved two previously unidentified chloride-binding sites. Through integrative molecular dynamics simulations and functional mutagenesis, our results support roles for chloride and the conserved residue E213 in substrate binding and proton-coupled transport. Together, our findings establish a structural framework for VIAAT-mediated inhibitory neurotransmitter transport that illuminates the molecular basis of inhibitory synaptic transmission and provides a foundation for understanding VIAAT dysfunction in epilepsy and related neurodevelopmental disorders.

neuroscience↗

bioRxiv2026

NEMP1 organizes the meiotic telomere LINC interface to control chromosome movement and telomere integrity

Nuclear Envelope Membrane Protein 1 (NEMP1) is highly expressed in oocytes and required for fertility, yet its meiotic function remains poorly understood. Here, we identify NEMP1 as a critical organizer of meiotic telomere-nuclear envelope coupling and chromosome dynamics. Loss of NEMP1 causes telomere aggregation, loss of shelterin protection, telomere shortening, persistent DNA damage, aberrant non-homologous end joining, and chromosome end-to-end fusion, ultimately leading to aneuploidy in mouse oocyte. NEMP1 is required during early fetal meiotic prophase I for telomere-nuclear envelope attachment, bouquet formation, homolog pairing, and synapsis. Live cell imaging revealed robust rapid prophase movements in wild-type meiocytes, which were nearly abolished by NEMP1 loss and restored by NEMP1-GFP re-expression. Mechanistically, NEMP1 associates with telomeric DNA and the SUN1-KASH5 LINC machinery, and SUN1-GFP restores chromosome movement in Nemp1-deficient meiocytes. Together, these findings establish NEMP1 as a nuclear-envelope organizer linking telomere protection, chromosome dynamics, and genome integrity during mammalian oogenesis.

developmental biology↗

bioRxiv2026

Phenolic Chemical Defense Contributes to Resistance against Multiple Soybean Cyst Nematode Populations in Wild Soybean

Soybean cyst nematode (Heterodera glycines, SCN) is one of the most damaging pathogens of soybean worldwide. Virulence diversity among SCN populations and reliance on a limited number of resistance sources present major challenges for durable SCN management. Here, we investigated a wild soybean (Glycine soja) genotype (WsR), that is resistant to two SCN populations, race 2 (HG type 1.2.5.7) and race 5 (HG type 2.5.7), and compared its transcriptional and metabolic responses with those of the susceptible genotype (WsS). WsR exhibited a substantially stronger defense-associated transcriptional response to both SCN populations, including preferential induction of genes associated with Ca2+/calmodulin and salicylic acid signaling. Integration of transcriptomic and time-resolved metabolomic analyses revealed convergence on phenolic metabolism, with enhanced accumulation of phenolic acids, flavonoids, and isoflavonoids in resistant WsR. Genes involved in phenolic biosynthesis and modification were also preferentially induced in WsR, linking transcriptional reprogramming with the observed metabolic response. Importantly, two resistance-associated phenolic compounds, 4-hydroxybenzaldehyde and 2,3-dihydroxybenzoic acid, directly increased mortality of SCN second-stage juveniles from both populations in a concentration-dependent manner. By connecting resistance-associated transcriptional responses and metabolic reprogramming with direct activity of specific phenolic compounds against SCN, our study provides functional evidence linking phenolic metabolism to chemical defense against SCN. Together, these findings identify enhanced phenolic chemical defense as a major component of resistance to multiple SCN populations in wild soybean and highlight wild soybean as a valuable source of molecular and biochemical diversity for SCN resistance.

plant biology↗

bioRxiv2026

DiffDomain-Spectrum identifies structurally reorganized TADs from sparse aggregated single-cell Hi-C contact maps

Structurally reorganized topologically associating domains (TADs) capture condition- or cell-type-specific remodeling of chromatin contacts and are important for understanding genome organization in health and disease. Emerging single-cell Hi-C (scHi-C) technologies enable such comparisons across heterogeneous cell populations, but aggregated scHi-C contact maps remain sparse at biologically meaningful 25 kb resolution, limiting reliable TAD reorganization detection. Here we present DiffDomain-Spectrum, a spectral statistical framework for identifying reorganized TADs between conditions or cell types from aggregated raw scHi-C contact maps. It tests normalized TAD-level difference matrices without separately normalizing sparse maps or enhancing individual scHi-C contact maps. Comparison with a semicircle-law null integrates evidence across the full eigenvalue spectrum. Across multiple scHi-C platforms, DiffDomain-Spectrum balances false positive control and detection sensitivity relative to alternative bulk callers, and detects a substantially higher proportion of reference TADs as reorganized than the boundary-focused single-cell method scHiCluster. Detected TADs show coherent aggregate contact patterns and CTCF binding changes and are enriched for differentially expressed genes, supporting biological relevance. Together, these results establish DiffDomain-Spectrum as a statistically principled framework for comparative domain-level analysis of sparse aggregated scHi-C contact maps without single-cell map enhancement.

genetics↗

bioRxiv2026

A genetically encoded redox bottleneck constrains human developmental rate

The intrinsically slow pace of human development poses challenges for regenerative medicine and disease modeling. This trait is attributed to low metabolic rates, yet the endogenous mechanisms determining species-specific metabolic flux remain unknown. Here, we identify coupling between glycolytic NADH production and mitochondrial oxidation through the glycerol-3-phosphate (G3P) shuttle as a genetic bottleneck constraining human developmental tempo. Using stem cell-derived models of the segmentation clock, an oscillator whose period reflects developmental rate, we show that low expression of the G3P shuttle enzyme GPD1L limits NADH oxidation in human progenitors compared to mouse. Overexpressing GPD1L boosts metabolic flux, accelerating the segmentation clock, cell cycle, and differentiation across germ layers. G3P-mediated redox coupling is thus a genetically encoded, rate-limiting mechanism that sets the tempo of human development.

developmental biology↗

bioRxiv2026

Genetic regulation of circulating metabolome in cattle

The circulating metabolome is a vital intermediate layer linking genetics to complex phenotypes, yet existing genome-wide studies-even in humans-rarely capture dynamic physiological contexts or cellular regulatory mechanisms. Here, we present the Cattle Metabolome Atlas (https://cattlema.farmgtex.org/), a comprehensive resource of 3,436 plasma metabolites and 4,851 serum metabolites from 4,651 animals with matched sequence-level genotypes across highly dynamic parity and lactation stages. We mapped 728 plasma and 622 serum metabolite quantitative trait loci (mQTL), revealing widespread context-dependent regulatory architectures. Integrating these mQTL with the multi-tissue expression quantitative trait loci (eQTL) and single-cell atlas of 59 tissues demonstrates that 74-79% of mQTL colocalize with eQTL across 29 tissues, prioritizing the liver as the primary systemic hub and resolving metabolic programs at single-cell resolution. Furthermore, we charted 538 causal gene-tissue-metabolite-trait cascades across 11 complex traits in cattle. Finally, cross-species analyses demonstrate partial evolutionary conservation of genetic metabolism between cattle and humans, establishing this atlas as a powerful asset for cattle genetics and genomics, selective breeding, and comparative biology.

genetics↗

bioRxiv2026

RNA-aware tissue preservation workflows for high-quality spatial transcriptomics

Image-based transcriptomic approaches can define, discover, and chart cell types and states within an array of tissues. However, measurement quality depends on RNA integrity, and the modern tissue preservation toolbox was not designed to protect this highly labile molecule. Here we leverage MERFISH to show that tissue-dependent differences in endogenous RNase activity can shape spatial transcriptomics data quality for different preservation methods and that RNase-activity-guided protocol optimization can improve data quality. In parallel, we introduce an RNA-aware pan-tissue preservation approach, Rapid Inhibition and Permanent Inactivation of Nucleases (RIPIN), that rapidly stabilizes samples with a broad-spectrum RNase inhibitor while permitting slow, chemical inactivation. RIPIN produces high-quality MERFISH measurements in all profiled human and mouse tissues, is compatible with clinical workflows, and is easily integrated with frozen or paraffin sectioning. By highlighting how RNA integrity can be lost during tissue processing, our work may inspire the next generation of RNA-aware histology methods.

genomics↗

bioRxiv2026

Integrating Narrow-Window DIA with AI-Powered Search Enables Deep and Reliable Functional Proteomics

Narrow-window data-independent acquisition (nDIA) is emerging as a powerful technique for bottom-up proteomics. Here, we systematically benchmarked nDIA, wide-window DIA (wDIA), narrow-window data-dependent acquisition (nDDA), and wide-window DDA (wDDA) for rapid, single-shot proteomic analysis. For data processing, we introduced Tesorai Search, a new search engine leveraging a large pre-trained model and compared it with DIA-NN and FragPipe across both DIA and DDA datasets. Among 12 acquisition-analysis pipelines evaluated, nDIA combined with DIA-NN and Tesorai Search delivered the highest proteome coverage, identifying 10,255 and 10,766 protein groups from benchmark samples, respectively. Both search engines maintained rigorous false-discovery rate (FDR) control. While nDIA generally outperformed nDDA in sensitivity, FragPipe-DDA+ approach proved to be the most sensitive within the nDDA pipelines. However, entrapment analyses indicate that this sensitivity comes at the cost of less robust FDR control compared to Tesorai Search. As a proof of concept, we applied nDIA-MS to 17 cancer cell lines harboring DNA damage response (DDR) gene knockouts, successfully detecting significant downregulation of all targeted proteins and uncovering 81 DDR-related proteins modulated in at least one cell line. These results underscore nDIA-MS, together with DIA-NN and Tesorai Search, as a robust and scalable platform for high-throughput functional proteomic screening.

systems biology↗

bioRxiv2026

Conformational dynamics of an intrinsically disordered receptor enable signal transduction

Signal transduction is initiated when activated cell-surface receptors physically engage intracellular signaling proteins. Although structural and biochemical studies have established the molecular architecture of receptor tyrosine kinase (RTK) signaling, the earliest dynamic events that couple receptor activation to intracellular signal propagation have remained inaccessible because existing approaches provide static structural snapshots or ensemble-averaged measurements rather than direct observation of molecular motion. Here, using high-speed atomic force microscopy (HS-AFM), we directly visualize these initial molecular events at the single-molecule level in real time. Using fibroblast growth factor receptor 1 (FGFR1) as a model, we show that receptor autophosphorylation releases its intrinsically disordered juxtamembrane region, enabling extensive conformational dynamics of the kinase domain that permit productive engagement of the signaling adaptor FRS2, a key initiator of downstream RTK signaling. In contrast, a kinase-inactive mutation or the clinically approved FGFR inhibitor futibatinib restricts receptor motion, stabilizes a compact receptor configuration, and markedly reduces adaptor engagement. Molecular dynamics simulations suggest that the disruption of inhibitory interactions between the juxtamembrane region and the kinase domain provides a structural explanation for the observed receptor dynamics. Together, our findings uncover a previously inaccessible physical mechanism underlying the initiation of RTK signaling and establish HS-AFM as a powerful platform for visualizing receptor dynamics, providing a framework for mechanistic studies of signal transduction and for the development and mechanistic evaluation of compounds that modulate receptor signaling.

biophysics↗

bioRxiv2026

Novel Dissymmetric Ionizable Lipid-Assembled Lipid Nanoparticles for Delivery of Ferroptosis-Related siRNA in Diabetic Treatment

Small interfering RNA (siRNA) enables precise post-transcriptional gene silencing for refractory diseases, yet its clinical translation remains limited by the lack of safe and efficient delivery vectors. Inspired by the dissymmetric alkyl chain architecture of natural membrane phospholipids, we designed and synthesized 34 novel ionizable lipids with dissymmetric hydrophobic tails and formulated them into lipid nanoparticles (LNPs). Through systematic physicochemical and biological assessments, we established clear structure-activity relationships and identified two lead LNPs (O14-LNP, H18a-LNP) with superior endosomal escape capacity, enhanced in vivo gene silencing potency, and favorable biosafety relative to the clinical benchmark MC3-LNP. In both streptozotocin-induced and spontaneous db/db type 2 diabetes (T2D) mouse models, lead LNPs delivering ferroptosis-related siRNAs effectively ameliorated glucose and lipid metabolic disorders, restored islet function, and alleviated hepatic steatosis. This study not only lays a theoretical foundation for the rational design of novel ionizable lipids, but also validates the therapeutic potential of siRNA therapy targeting ferroptosis, providing a versatile delivery platform and targeted therapeutic strategy for the treatment of T2D.

pharmacology and toxicology↗

bioRxiv2026

The function of human PIF1 in G quadruplex formation and replication stress response at ALT telomeres

Cancers maintain their telomeres through two telomere maintenance mechanisms: 85-90% of cancers rely on telomerase (TEL+), while 10-15% of cancers adopt the Alternative Lengthening of Telomeres (ALT) pathway. The Break-Induced Replication (BIR) pathway plays a critical role in maintaining telomere length in the ALT+ cells. In both yeast and human, PIF1, a 5' to 3' helicase, is required for the robust activity of BIR. However, the extent of human PIF1 (hPIF1) involvement in the ALT pathway remains unknown. Here we showed that hPIF1 can be recruited to damaged telomeres in ALT+ cells. In addition, we demonstrated that inhibition of hPIF1 induced DNA damage and G quadruplex (G4) accumulation at ALT telomeres, leading to a moderate reduction of the mean telomere length. Most interestingly, we demonstrated that inhibition of hPIF1 also attenuates checkpoint activation, BLM recruitment, single-stranded DNA (ssDNA) formation, DNA damage, and G4s at telomeres in the FANCM deficient ALT+ cells. Finally, we showed that inactivation of hPIF1 affects the viability of both ALT+ and TEL+ cancers, suggesting that hPIF1 is a potential drug target for cancer therapy.

molecular biology↗

bioRxiv2026

Highly plastic macrophage niches orchestrate acquired quiescence and reactivation in breast-cancer bone metastasis

Recurrence and metastasis remain major causes of cancer mortality, sustained by therapy-resistant micrometastatic cells. Bone is a frequent site of breast-cancer relapse, yet the cues that reawaken disseminated cells remain poorly defined. We identify a previously unrecognized, highly plastic CXCL16 macrophage population that integrates tumor-associated macrophage programs found in distant metastatic sites such as lung and brain with non-tumor disease-associated traits in bone marrow. These CXCL16 macrophages establish a transient niche that restrains disseminated cancer-cell proliferation. Single-cell transcriptomics delineate functional remodeling of myeloid niches within the bone metastatic microenvironment: a CXCL16 macrophage niche that transiently constrains metastatic growth, and G-CSF macrophage and neutrophil niches that reignite tumor outgrowth. In primary tumors, cancer-associated fibroblasts (CAFs) aberrantly secrete G-CSF in response to cancer-cell signals, expanding G-CSF-receptor-positive subset of cancer cells with high metastatic potential. In advanced human bone metastases, CXCL16 macrophages localize to CAF-rich stroma but are excluded from cancer-cell clusters, indicating immune evasion. Together, these findings uncover CAF-bone-marrow cross-talk as a therapeutic target linking stromal inflammation, immune remodeling, and metastatic progression.

cancer biology↗

bioRxiv2026

A Vibrio parahaemolyticus transcriptome map captures conserved and specific regulators

Bacterial sRNAs are pervasive post-transcriptional regulators, yet how they arise, evolve, and decay remains poorly understood. Here, we provide a high-resolution transcriptome map and curated sRNA set for the pathogen Vibrio parahaemolyticus. We identify over 100 sRNAs, including broadly conserved, lineage-specific, and previously unidentified transcripts, as well as dual-function regulatory/coding sRNAs. Functional analysis of several examples highlights conserved and lineage-specific regulators of metabolism and flagella. Broadly conserved VcrX represses chitin utilization genes and may regulate Vibrio Spot 42, which we confirm is translated. We expand on FlaX regulation of polar flagella across the genus by demonstrating that the sRNA differentially activates/represses downstream flagellins, with a potential FlaX sponge mediating feedback in specific clades. We further show that V. parahaemolyticus, but not V. cholerae, RyhB is translated into a Cys-rich small protein that could regulate related pathways. Together, these findings establish a resource for Vibrio and a platform for comparative studies of post-transcriptional regulation, enabling investigation of how sRNAs and their regulatory networks evolve.

microbiology↗

bioRxiv2026

A closed-loop reinforcement learning framework for rapid compound directed optimization

Generative artificial intelligence (AI) holds transformative potential for drug discovery, yet existing architectures typically operate in open loops without experimental feedback. Here we introduce rapid compound directed optimization (RCDO), a closed-loop reinforcement learning framework that accelerates the optimization process by bridging dry-lab computation with wet-lab feedback. RCDO couples a three-dimensional structure-guided generative model with a multi-level reward system updated after each design cycle using experimental measurements from all synthesized compounds, including inactive or developability-failed compounds. By continuously aligning the generative model with accumulated wet-lab measurements, RCDO substantially compresses optimization timelines. We evaluated RCDO through retrospective benchmarking against historical optimization trajectories and prospective wet-lab campaigns targeting ROR1, NLRP3, and NSD3. Across prospective evaluations, RCDO rapidly resolved key optimization bottlenecks within two to three design cycles: improving the oral exposure of an ROR1 inhibitor by 40-fold while maintaining antitumor efficacy, reducing CYP2C19 inhibition of an NLRP3 antagonist by 20-fold while preserving inflammasome activity, and boosting the binding affinity of an NSD3 hit by 18-fold. By directly coupling wet-lab feedback to generative learning, RCDO establishes an efficient platform for compound directed optimization, transforming AI-driven drug discovery from static generation into continuous experimental adaptation.

bioinformatics↗

bioRxiv2026

Factorial Knockouts Distinguish Physical Necessity from Numerical Compensation in a PSI-LHCI Transport Model

Mechanistic interpretation of photosynthetic energy-transfer models requires more than reproduction of experimental observables: a model intended to support mechanistic claims should also respond consistently when its proposed functional organizations are removed. Here, we evaluate whether a calibrated PSI-LHCI transport surrogate encodes physically meaningful principles by applying a 2x2 factorial knockout framework that independently removes site-energy heterogeneity and coupling-strength heterogeneity in a 155-pigment network. All perturbations were evaluated using the same Full-model calibration without parameter refitting. Although the calibrated model reproduced a high excitation-trapping yield, eliminating either energetic or coupling heterogeneity unexpectedly improved its apparent transport performance. A strict zero-coupling control confirmed that coupling itself remained necessary for network-mediated reaction-center access, whereas the supplied organization of coupling strengths was not supported by the surrogate. An audit of the model inputs further identified peripheral localization of all lowest-energy states and effective coupling scales far above those used in structure-based chlorophyll Hamiltonians. These findings do not imply that native PSI favors flat energy landscapes or uniform couplings. Instead, they show that endpoint agreement alone does not validate a mechanistic interpretation of a pigment-network model. Factorial knockout analysis provides a falsification-oriented framework for separating physical necessity from proposed organization, diagnosing numerical compensation, and identifying the constraints required for more predictive models of PSI-LHCI energy transfer.

biophysics↗