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Biology subjects

Zhao, S.

Publications and source records attributed to Zhao, S..

At least 37 records · Page 2Linked to original sources

Super-Resolution Visual ProteomEx for Hard Tissues and Clinical Samples

Correlating nanoscale tissue architecture with unbiased molecular composition within the same specimen remains a fundamental challenge in spatial biology. Current spatial proteomics methods either lack the imaging resolution required to resolve nanoscale tissue architecture or achieve only limited proteome coverage, and untargeted approaches capable of deep protein identification have yet to be integrated with super-resolution imaging within a single workflow. Here, we present microProteomEx, an integrated platform that combines hydrogel-assisted tissue expansion with mass spectrometry-compatible fluorescence imaging, laser capture microdissection, and bottom-up proteomics to achieve simultaneous three-dimensional super-resolution imaging (effective lateral resolution down to [~]47 nm on conventional diffraction-limited microscopes) and spatially resolved proteomics at a scalable lateral resolution of 29-100 {micro}m (0.02-0.28 nL volumetric resolution). By optimizing fixation, protein anchoring, and a secondary re-embedding strategy, we extend the method to mechanically resilient tissues, including mouse kidney and heart, as well as to formalin-fixed, paraffin-embedded clinical specimens. We demonstrate single-glomerulus and single-plaque proteomics (450-1,000 proteins per structure), resolve proteomic differences between malignant melanoma and giant congenital melanocytic nevus in a rare pediatric case, and characterize the morphology-resolved molecular heterogeneity of cored versus diffuse amyloid-beta plaques in a mouse model of Alzheimers disease across two disease stages. microProteomEx establishes a broadly accessible framework for correlating tissue ultrastructure with deep spatial proteomics, with direct implications for disease biology, biomarker discovery, and precision medicine.

biochemistry↗

Doublesex- mediated regulation of insulin signaling drives sex-specific body growth

Most animals develop sex-biased body sizes driven by sexually divergent plasticity in nutrient-dependent growth. Prior work in Drosophila, implicated the sex-determination gene transformer (tra) in regulation of sex differences in body size. However, tra does not widely mediate sex determination across insects. Thus, the unifying molecular pathway governing female-biased sexual size dimorphism (SSD) remains poorly established in non-drosophilid insects. The rice stem borer Chilo suppressalis, a devastating lepidopteran crop pest, exhibits a robust SSD, offering an ideal system to dissect underlying mechanisms. We report that female-specific splice forms of the sex-determining gene doublesex (Csdsx) are master regulators of female-biased growth. Disruption of the female-specific Csdsx exon 3 via CRISPR knockout or RNA interference drastically reduces female body size and completely erases the SSD. Csilp2, encoding a key insulin-like peptide (ILP2), is selectively upregulated in late-instar female larvae, and female CsDsx proteins directly bind and activate the Csilp2 promoter to boost transcription. Loss-of-function of Csilp2 eliminates the SSD by suppressing female somatic overgrowth. Our results identify a novel regulatory cascade: female-specific Dsx directly stimulates insulin signaling via Csilp2, bridging core sex-determination circuitry and nutrient-dependent body growth control. SignificanceSexual size dimorphism (SSD), widespread across insects with larger females, strongly shapes reproductive fitness. Yet reports on the molecular connection between sex determination and dimorphic growth are scarce. Using a major agricultural pest, the rice stem borer with a prominent female-biased SSD, we show that female-specific Doublesex (dsx) splice variants directly activate the promoter of Insulin-like peptide 2 in late larvae to trigger increased growth. Knocking out either gene in females abolishes the SSD. Our findings thus establish dsx as a novel link connecting sex-determination, insulin signaling and nutrient-dependent body growth.

Developmental Biology↗

Catalytic rewiring of RuvC-II catalytic site activates trans-cleavage in Fanzor2

Fanzors are eukaryotic RNA-guided endonucleases that mediate programmable cis-cleavage in eukaryotic cells, but their potential target-induced collateral (trans) cleavage activity remains largely unexplored. Here, we show that catalytic rewiring of the RuvC-II catalytic site activates robust trans-cleavage activity in Acanthamoeba polyphaga mimivirus Fanzor2 (ApmFz2). The representative variant ApmFz2-EP displayed DNA- and RNA-triggered trans-cleavage, attenuated cis-cleavage, minimal TAM dependence, and activation by as few as seven nucleotides of guide-target complementarity. Mechanistic analyses indicate that relieving steric constraints surrounding the conserved alternative glutamate within the RuvC-II activates trans-cleavage and reshapes target-recognition specificity. Coupling ApmFz2-EP with nucleic acid amplification enabled FINDER, a Fanzor-based diagnostic platform for sensitive pathogen detection and broad detection across genetically diverse target subtypes. In addition, the mismatch-sensitive ApmFz2-EA variant enabled specific single-nucleotide variant (SNV) genotyping. Together, this work expands the functional scope of Fanzors and identifies catalytic-center engineering as a strategy for developing compact, programmable nucleic acid diagnostics.

bioengineering↗

A hippocampal neuroimaging signature of neurovascular insulin signalling links metabolism to mood

Depression is a leading cause of global disability and is increasingly linked to systemic metabolic dysfunctions, including insulin resistance. However, the biological pathways connecting metabolic state to affective symptoms are unresolved. A growing body of evidence indicates that insulin, beyond its role in systemic glucose homeostasis, supports brain metabolism, synaptic function and cognition, yet its contribution to mood regulation remains unclear. Here, we identify a human hippocampal metabolic signature associated with glycaemic variation in individuals with depression. Using multimodal neuroimaging, we show that hippocampal concentrations of GABA and lactate correlate with HbA1c and with mood severity, while functional connectivity between the hippocampus and the default mode network tracks affective symptoms independently of adiposity. To causally probe these relationships, we generated a mouse model of hippocampus-specific insulin receptor depletion. Unexpectedly, reducing insulin signalling at the blood brain barrier enhanced neuronal metabolism and attenuated anxiety-like behaviour. Notably, hippocampal lactate and GABA levels similarly tracked anxiety-related behaviour in mice, mirroring their association with symptom severity in humans. Together, these findings identify a conserved neurometabolic signature linking hippocampal insulin signalling to affective state, and reveal that brain insulin resistance exerts context- and cell-type-specific effects on behaviour. This work establishes a mechanistic basis for brain insulin resistance in depression and highlights the hippocampus as a critical hub for metabolic modulation of mood.

neuroscience↗

X-Gutor: a high-fidelity in vitro platform for long-term gut microbiome recovery

In vitro gut microbiome-culturing models are essential for studying host-microbe interactions, yet achieving high microbial recovery and long-term stability remains a long-standing challenge. Here we devise X-Gutor, an ecologically designed in vitro platform that recapitulates the monogastric digestive system with precise control of pH, redox potential, and a mucin-based biofilm matrix. Using an integrated assessment framework, microbial source tracking, a curated gut metabolism database (GutDB), and short-chain fatty acid profiling, we benchmarked gut community recovery. Building on this platform, HanGutor and PigGutor were developed to recover 96.27{+/-}4.92% and 90.48{+/-}5.95% of human and swine gut microbiota, respectively. Ecological fine-tuning revealed that redox potential drives the Prevotella-Bacteroides trade-off and that spatial biofilm structure suppresses cheater (Succinivibrio) growth. The X-Gutor provides a scalable, modular platform for gut microbiome engineering, dietary intervention, and microbiota-targeted therapy development.

microbiology↗

Dual histone methylation reader ZCWPW2 links histone methylation to initiation of meiotic recombination

Meiotic homologous recombination initiates with the formation of programmed DNA double-strand breaks (DSBs) by complexes comprising SPO11 and accessory proteins at discrete sites called recombination hotspots. In mammals, PRDM9-dependent H3K4me3 and H3K36me3 define recombination hotspots, but how these epigenetic characteristics determine the physiological DSB formation remains unknown. Here we show that dual histone methylation reader ZCWPW2 can recognize H3K4me3 and H3K36me3 marks in testis. The binding activity of ZCWPW2 to histone methylation is dependent on PRDM9 function. Moreover, we find the epigenetic writer-reader axis PRDM9-ZCWPW2 is essential for DSB formation at meiotic recombination hotspots, which may be partly explained by the finding that ZCWPW2 can physically interact with HORMAD1, IHO1, MEI4, and REC114. Finally, the absence of ZCWPW2 leads to disrupted chromosomal synapsis and recombination, thereby obstructing meiotic progression. Taken together, our findings provide new insights into how histone modifications and their associated regulatory proteins collectively regulate meiotic homologous recombination initiation.

cell biology↗

Ferrous Iron Accumulation Is a Hallmark and Therapeutic Vulnerability of Therapy-Induced Senescence

Chemotherapy and radiation reduce tumor burden but leave behind residual cells that survive via therapy-induced senescence (TIS). These cells constitute a latent reservoir fueling recurrence, yet strategies for their selective elimination are lacking. Here, we identify lysosomal ferrous iron accumulation as a conserved hallmark and actionable vulnerability of TIS tumor cells. Across diverse models, senescent tumor cells exhibit marked hypersensitivity to ferroptosis induction. In breast cancer PDX models, sequential ferroptosis induction following chemotherapy significantly delays recurrence, while dual inhibition of GPX4 and FSP1 produces durable, often complete, eradication of residual tumors without overt toxicity. Mechanistically, activation of the TFEB-HO-1 axis in TIS tumor cells drives ferrous iron accumulation, thereby priming cells for ferroptosis. Together, these findings establish ferrous iron accumulation as a defining feature of TIS and position ferroptosis induction as a potent senolytic strategy to eliminate therapy-refractory residual disease. Statement of significanceSenescent tumor cells remaining after treatment can drive cancer recurrence yet remain poorly understood and therapeutically intractable. Here, we identify lysosomal ferrous iron accumulation as a universal hallmark of therapy-induced senescence and demonstrate that ferroptosis induction functions as an effective senolytic strategy. Our findings provide mechanistic and translational support for the "one-two punch" therapeutic paradigm.

cancer biology↗

Multi-layer transcriptomic characterization of age-related immune dynamics

Despite the pivotal role of mRNA isoform diversity in governing immune cell function, current investigations into peripheral immune aging predominantly focused on gene-level expression, obscuring deeper regulatory layers of transcriptome complexity. Here, we leveraged a 5' scRNA-seq atlas comprising approximately 2.5 million PBMCs from 378 healthy donors. We demonstrate that immune aging is characterized by profound, non-linear transcriptional reprogramming that extends beyond gene-level shifts to include fine-tuned regulation of alternative transcription initiation and splice site selection. By quantifying the transcriptional activity of cis-regulatory elements, we resolved their contributions to age-related expression dynamics. Notably, we identified a subset of endogenous retroviruses that are reactivated in older individuals, some of which served as alternative promoters driving the production of chimeric transcripts. Furthermore, our analysis revealed EDA as a top-ranked gene consistently upregulated with age across multiple independent cohorts. Increasing EDA expression in in vitro-stimulated naive CD4+ T cells from young individuals recapitulated aged phenotypes. This comprehensive resource elucidates the multi-layered transcriptomic landscape of the aging immune system and facilitates the identification of novel drivers of immune aging.

bioinformatics↗

CANCAN: high-resolution copy number and mutation heterogeneity analysis of DNA sequence data for clinical applications

High-throughput DNA sequencing is central to precision oncology, yet robust and interpretable methods for integrated analysis of copy number alterations and somatic variants across sequencing platforms remain limited. We present CANCAN (Copy number integrative ANalysis in CANcer), a platform-agnostic computational framework for high-resolution analysis of allele-specific copy number and variant data. CANCAN integrates novel normalization and segmentation strategies and enables inference of tumor purity, ploidy, subclonality and mutation multiplicity, while providing statistical confidence estimates and transparent evaluation of alternative solutions. Benchmarking across whole-genome, whole-exome and targeted sequencing datasets from TCGA and the IMPRESS-Norway study demonstrates high concordance with established methods, with particularly strong performance on targeted sequencing data. CANCAN accurately estimates global genomic features, including purity and ploidy, even at reduced sequencing coverage, and shows comparable or improved agreement relative to existing tools. In addition, it provides detailed visualization of the genomic context of clinically relevant biomarkers, supporting diagnostic interpretation. CANCAN constitutes a reproducible and interpretable approach for integrated genomic analysis, addressing key methodological and practical challenges in clinical cancer genomics.

bioinformatics↗

AAV-NRF2 protects retinal and choroidal vasculature in a GDF15-dependent manner in an oxidative damage model of AMD

Oxidative stress is proposed to be a driver of age-related diseases. Age-related macular degeneration is one such disease, where the retinal pigment epithelium (RPE) is affected early in the disease. Vasculature damage also occurs, sometimes preceding RPE damage. To model some aspects of dry AMD, we used the NaIO3 mouse model of oxidative damage. Disruption of the deep retinal vascular plexus, disorganization and death of capillaries within the choriocapillaris, and marked electroretinographic decline were observed. AAV overexpressing the transcription factor, NRF2, which induces anti-oxidation enzymes and represses inflammation, was tested for protection of damage. The BEST1 promoter limited expression to the RPE. The RPE, photoreceptors, and vascular architecture in both retinal and choroidal compartments were protected. Conditioned medium from RPE-choroid explants, infected by AAV8/BEST1-NRF2, was sufficient to transfer partial protection in vivo, indicating that NRF2 induces a protective secreted factor(s). Analysis of RNA-seq data identified growth differentiation factor 15 (GDF15) as a candidate downstream mediator. Injection of recombinant GDF15 reproduced key protective phenotypes in vivo, whereas Gdf15-deficiency attenuated NRF2-mediated rescue. Pharmacologic inhibition of TGF-{beta} receptor signaling diminished NRF2 associated protection, supporting involvement of this signaling pathway. In a laser-induced choroidal neovascularization model, intravitreal GDF15 injection reduced fluorescein leakage and lesion size. These findings support a model in which NRF2 activation in the RPE induces expression of GDF15, which is capable of protecting the RPE, photoreceptors, and the retinal and choroidal vasculature. NRF2 and GDF15 have therapeutic potential for ocular diseases, as well as for other diseases with vascular pathology.

cell biology↗

Automated Multimodal Correlative Registration for Organelle-Specific Molecular Imaging

Mapping subcellular drug distribution is essential for understanding trafficking and off-target effects. NanoSIMS enables chemical imaging of labeled therapeutics, but signal interpretation requires ultrastructural correlation with electron microscopy, a manual and laborious process. We present an automated AI-driven pipeline for correlating chemical and ultrastructural images, enabling multiscale, organelle-precise imaging of molecules in cells and tissues. The method integrates bidirectional optical flow, confidence-guided affine transformation, and automated template matching for cross-scale EM alignment. Morphology-rich ion channels (e.g., 32S) estimate transformations that propagate to sparse therapeutic signals (e.g., 79Br, 15N), overcoming low signal-to-noise challenges. We validate this framework across diverse cell and tissue types, tracking oligonucleotide and antibody therapeutics in vitro and in vivo to reveal cell-type- and organelle-specific distribution patterns. This work establishes a generalizable platform for automated multimodal registration and organelle-resolved subcellular pharmacology.

bioinformatics↗

Connecting polygenic disease risk to cell states and regulatory programs through single-cell chromatin accessibility

Single-cell ATAC-sequencing enables high-resolution mapping of cell states and their putative regulatory elements. The enrichment of genome-wide association study (GWAS) signals within context-specific regulatory regions can reveal disease-relevant cell populations. We present Single-Cell ATAC-seq Disease Score (SCADS), a computational framework that integrates GWAS summary statistics with scATAC-seq data to prioritize disease-relevant cells. SCADS produces calibrated, cell-level scores that are comparable across datasets and traits by: (i) identifying chromatin co-regulatory regions via topic modeling, (ii) quantifying their polygenic GWAS enrichment, and (iii) calculating cell-specific disease scores from topic weights and enrichment levels. Across extensive simulations, SCADS outperforms existing methods in power while controlling false positives. Applied to multiple autoimmune traits, SCADS reveals marked heterogeneity in disease relevance within canonical immune cell types. We specifically studied the differential disease relevance within CD8+ T and colon epithelial cells for inflammatory bowel disease, and pinpointed underlying gene programs and variants. SCADS is scalable, interpretable, and modular, providing a general framework to connect noncoding regulatory variation to cellular identity and function.

genomics↗

Hypermorphic TaARF4 shapes wheat architecture by repressing SPL-mediated developmental timing

Integrating spatial morphogens with temporal developmental clocks is fundamental to optimizing plant architecture and crop yield, yet their molecular interface remains elusive. Here, we characterize Branched shoot 1 (Bsh1), a semi-dominant wheat mutant exhibiting non-canonical upper-aerial branching and aberrant spike development, caused by a T265I substitution in the DNA-binding domain of the auxin response factor TaARF4-A2. Unlike flanking mutations governing protein stability in basal land plants, this central substitution uniquely converts TaARF4-A2 into an auxin-insensitive hypermorphic repressor. The mutant protein disrupts auxin-cytokinin homeostasis and markedly enhances the native repression of SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors, the core timers of developmental phase transitions. This spatial and temporal uncoupling unleashes upper axillary buds from dormancy, promoting aerial branching and diverting resources from reproductive development. Our findings demonstrate how a conserved spatial morphogen effector was evolutionarily rewired in polyploid wheat to dictate the temporal SPL clock, orchestrating species-specific shoot architectural innovation.

plant biology↗

Tartrazine clears live cells while preserving viability at high refractive indices and osmolality

Tissue-clearing techniques have transformed optical imaging of fixed specimens, yet their application to living systems remains limited by toxicity and removal of key tissue components. We recently demonstrated that absorbing molecules such as tartrazine can reversibly render live mouse skin transparent. Subsequently, it was reported that isotonic protein solutions can achieve ex vivo and in vivo cellular clearing. However, discrepancies remain regarding the optimal refractive index (RI) for live-cell clearing and the impact of elevated osmolality on cell viability. Here, using cultured mammalian cells, we systematically examine the dependence of optical contrast on medium RI and the effects of hyperosmolality. We find that, contrary to the recent report of an optimal RI of 1.36[~]1.37 for suspended cells, densely-packed adherent cells exhibit a monotonic decrease in phase contrast up to an RI of 1.41 with tartrazine. Moreover, even under highly hyperosmotic conditions ([~]1200 mOsm/kg), cultured cells exhibit minimal deformation and negligible loss of viability for up to 30 min in the clearing solution. These results demonstrate that tartrazine enables effective live-cell clearing at RI up to 1.41 while preserving viability under elevated osmolality, and motivate future studies to define optimal conditions for in vivo optical clearing. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=44 SRC="FIGDIR/small/717314v1_ufig1.gif" ALT="Figure 1"> View larger version (17K): org.highwire.dtl.DTLVardef@1ec9fbforg.highwire.dtl.DTLVardef@1ebe9e6org.highwire.dtl.DTLVardef@1492c3corg.highwire.dtl.DTLVardef@f75559_HPS_FORMAT_FIGEXP M_FIG C_FIG

biophysics↗

Continental-scale multi-omics reveals a distinct microbial-viral biome in sandy beach ecosystems structured by tidal zonation

Sandy beaches are dynamic coastal interfaces shaped by strong physical forcing and intense exchange between marine and terrestrial environments, yet their microbiomes remain poorly resolved at the genomic scale. Here we present a genome-resolved survey of microbial and viral communities across sandy beaches spanning a continental-scale latitudinal gradient along the Chinese coastline. By integrating cross-shore sampling, coastal geochemistry and large-scale multi-omics, we generated 978 metagenomes, 63 viromes and 72 metatranscriptomes, reconstructing 13,337 metagenome-assembled genomes and 38,255 viral populations. Sandy beach microbiomes exhibit exceptionally high genomic novelty, with more than 90% of species-level genomes representing previously undescribed taxa, suggesting that permeable coastal sediments constitute a distinct microbial and viral reservoir. Tidal zonation emerged as a dominant ecological driver structuring microbial diversity, metabolic strategies and virus-host interactions across cross-shore gradients. Genome-resolved analyses revealed systematic metabolic shifts from oxic heterotrophy in supratidal sediments toward increasingly chemolithotrophic and autotrophic pathways toward the low-intertidal and subtidal zone. Sandy beach microbiomes further encode broad potential for hydrocarbon and plastic transformation, together with diverse biosynthetic and antibiotic resistance repertoires that may mediate microbial chemical interactions. Together, these findings identify sandy beaches as a previously under-recognized microbial-viral biome shaped by tidal forcing, providing insight into microbiome evolution and coastal ecosystem resilience under increasing anthropogenic pressure.

microbiology↗

Detecting context-dependent selection on cancer driver genes with DiffDriver

Positive selection on somatic mutations is the driving force for cancer progression. Growing evidence shows that the emergence of a driver mutation in a tumor sample depends on individual-specific factors, for example environmental exposures or the individuals germline genetic background. We term these individual-level factors as the "contexts" of a tumor. Our hypothesis is that mutations in a driver gene can bring different growth advantages in different contexts, resulting in "differential selection" on these genes in varying contexts. Identifying which contexts modulate selection strength provides critical insights into the selection forces driving tumorigenesis. However, due to the sparsity of somatic mutations and heterogeneous background mutational process across positions and individuals, identification of differential selection has limited power with current statistical tools and is prone to false positives. To address this, we developed a powerful statistical method, DiffDriver, that identifies associations between "contexts" and selection strength on a driver gene across individuals. DiffDriver accounts for variations of mutation rates across bases and individuals, while taking advantage of functional information of sequences to improve the power. Through simulations, we show DiffDriver reduces false positives and boosts power compared to current methods. Our results highlight that multiple individual-level factors create significant heterogeneity in the strength of selection acting on driver genes and 33% of driver genes showed differential selection in at least one of the contexts studied, including tumor clinical traits and tumor immune microenvironment subtypes. These results provided new insights into the context-dependent forces driving cancer evolution.

genomics↗

Extensive genomic diversity in Desulfovibrio species reveals species-specific functional traits associated with disease

Desulfovibrio spp. are associated with inflammatory diseases and human health, yet limited representative genomes and isolates hinder our understanding of their role in disease. Here, we assembled a comprehensive database of 2,658 Desulfovibrio genomes across 90 diseases and 32 countries, including 24 human isolates. Genomic analyses showed extensive species diversity and revealed disease-associated functional traits, including flagellin and virulence genes (i.e. ureases). Flagellin-mediated Toll-like receptor 5 activation was species-specific and D. desulfuricans flagellin downregulated TGF-beta signalling in murine small intestinal organoids, suggesting impaired immune tolerance. Additionally, we investigated genomic capacity for hydrogen sulfide (H2S) production, a main Desulfovibrio metabolite. While health- and disease-associated Desulfovibrio spp. mainly encoded dissimilatory sulfate reduction, tetrathionate metabolism-encoding bacteria were exclusively detected in inflammatory bowel diseases, including Proteus mirabilis and Morganella morganii. Overall, our study provides a comprehensive genomic Desulfovibrio resource and identifies new links associating strain variation, functional traits and H2S-production with inflammatory diseases.

genomics↗

The enhanced multi-tissue atlas of regulatory effects in cattle

Cattle are integral to global food security, yet the molecular architecture of their complex traits remains poorly understood. Here, we present the Cattle Genotype-Tissue Expression (CattleGTEx) Phase 1 resource (https://cattlegtex.farmgtex.org/), a substantial expansion of the pilot study. By leveraging 12,422 RNA-seq profiles across 43 tissues and 82 breeds, we characterized 433,972 primary and 161,428 non-primary regulatory effects spanning seven molecular phenotypes. This high-resolution atlas resolves 75% of GWAS signals for 44 complex traits, significantly addressing the "missing regulation" in livestock. We propose a genetic regulatory model demonstrating how variants across multiple biological layers interact with specific biological contexts to shape phenotypic variation. Furthermore, CattleGTEx elucidates mechanisms underlying adaptive evolution between Bos taurus and Bos indicus, as well as artificial selection in dairy and beef breeds. Finally, by mapping evolutionary constraints on these regulatory effects, we demonstrate the translational value of this resource for prioritizing causal variants in human complex diseases. Together, Phase 1 of CattleGTEx provides a transformative framework for functional genomics, precision breeding, and comparative genetics.

genetics↗