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Zhou, C.

Publications and source records attributed to Zhou, C..

At least 37 records · Page 2Linked to original sources

Plant MutS Homolog 1 is a mismatch-directed nuclease required for organelle genome maintenance

The exceptionally low mutation rates of plant organellar genomes imply the existence of DNA surveillance mechanisms that counteract replication errors and DNA damage. Genetic evidence implicates MutS HOMOLOG 1 (MSH1) as a central component of this pathway, as loss of MSH1 results in the accumulation of point mutations. MSH1 is a unique protein that combines an N-terminal MutS-like mismatch-recognition module with a Cterminal GIYYIG nuclease domain. Here, we show that Arabidopsis thaliana MSH1 (AtMsh1) recognizes mismatches, insertion/deletion loops, and damaged bases within double-stranded DNA and introduces staggered DNA breaks at positions flanking the mismatch or lesion. Given the presence of an active homologous recombination machinery in plant organelles, we hypothesize that these DNA ends may be processed by exonucleases to remove the mismatched or damaged DNA while generating 3' single-stranded DNA substrates suitable for homologous recombination-mediated repair and gene conversion. Together, our findings support a model in which AtMsh1 functions as a minimal mismatch repair system that couples mismatch recognition to DNA incision, providing a potential mechanism for suppressing mutation accumulation and maintaining the remarkable stability of plant organellar genomes

biochemistry↗

Nature-inspired Nanoparticle Adiposomes Enable Targeted Delivery of Hydrophobic Drug for Anti-Cancer Treatment

The predominance of hydrophobic molecules in drug pipelines poses a fundamental delivery challenge in the aqueous physiological environment. Inspired by the endogenous lipid-transport machinery of lipid droplets and lipoproteins, adiposome was developed as a biocompatible platform for hydrophobic drug delivery. Here, docetaxel (DTX) was selected as a model hydrophobic chemotherapeutic agent to evaluate the therapeutic versatility of adiposome. Non-targeted DTX-loaded adiposomes (DTX-Ad) reduced systemic toxicity by avoiding the allergenic excipients Tween 80 and ethanol used in commercial DTX formulations. The cytotoxic mechanism and intracellular responses of DTX-Ad were comprehensively characterized. To boost antitumor efficacy, three tumor-targeting DTX-Ad formulations were subsequently engineered. Lung-targeting DTX-adiposomes (Lung@DTX-Ad), mediated by AAM-B1-28-CRGDK fusion peptide/NRP1 axis, enhanced antitumor efficacy in a lung metastasis model. BCMA-targeting DTX-adiposomes (BCMA@DTX-Ad), conferred by biotin-avidin-mediated antibody conjugation, achieved sustained suppression in a multiple myeloma model. Liver-targeting DTX-adiposomes (Liver@DTX-Ad), enabled by the ApoE/LDLR axis, outperformed both commercial DTX injection and sorafenib in hepatocellular carcinoma models. Taken together, these results demonstrate adiposome as a promising and broadly applicable drug delivery platform, with considerable potential for clinical translation across diverse malignancies.

cancer biology↗

Amino Acid Stress Induces Non-AUG Initiation of c-myc Translation

Initiation of translation at non-AUG start codons can generate novel isoforms of important cellular regulators, with activities or localization distinct from their AUG-initiated counterparts. Ribosomes scanning the 5UTR upstream of canonical AUG starts recognize near-cognate starts inefficiently, however, and the mechanisms by which non-canonical starts might be regulated physiologically are poorly understood. We show here that the restriction of utilization of individual amino acid induces a switch in expression of c-myc from its AUG-initiated isoform, c-myc-2, to an upstream CUG-initiated isoform, c-myc-1. This switch is enhanced in cells lacking GCN2, the protein kinase linking amino acid stress to phosphorylation and inhibition of eif2. Induction of upstream CUG start site usage in c-myc by restriction of proline utilization depends on the proximity of proline codons downstream of the canonical AUG start site. These observations support a model in which the stalling of an elongating ribosome near a canonical start leads to the accumulation of a ribosome queue that facilitates initiation at an upstream non-canonical start site. We find similar effects associated with deprivation of amino acids other than proline, and isoform changes with ATF-3 as well as c-myc. These findings suggest a broad mechanism by which amino acid stress can regulate translation initiation site use to modify the N-terminal proteome.

cell biology↗

PD-1 remodels SHP2 dynamics and drives the non-catalytic inhibition of T cell activation

The inhibitory receptor programmed cell death protein 1 (PD-1) suppresses T cell activation primarily by recruiting the src homology 2 domain-containing phosphatase 2 (SHP2), thereby unleashing its phosphatase activity. However, a purely enzymatic model struggles to fully explain the rapid and robust disruption of proximal T cell receptor (TCR) and CD28 signaling. Here, by integrating X-ray crystallography, single-molecule magnetic tweezers, supported lipid bilayers, TIRF imaging, liquid-liquid phase separation, and cellular assays, we uncover a dual-layered inhibitory mechanism of the PD-1/SHP2 axis. Mechanistically, we determine the crystal structure of SHP2 in complex with dually phosphorylated PD-1 cytoplasmic motifs (pPD-1), revealing a ligand-induced open conformation, which is distinct from the oncogenic E76K-associated state. We further directly resolve the closed-to-open conformational dynamics of individual SHP2 molecules, characterized by an 8-nm transition amplitude, and demonstrate that pPD-1 accelerates the transition by at least 94-fold. Crucially, the pPD-1-mediated highly open conformation exposes the tandem SH2 (t-SH2) domains to function as a biophysical barrier. Independent of phosphatase activity, these domains directly dismantle pTCR and pCD28 signaling condensates to suppress T cell activation. Together, our findings establish a model in which pPD-1 remodels SHP2 structural dynamics and drives a non-catalytic inhibitory mechanism of TCR and CD28 signaling, suggesting next-generation immunotherapy design to reverse T cell suppression.

immunology↗

Hierarchical Interplay between H3K27ac and H3K4me3 in Transcriptional Regulation

H3K27ac and H3K4me3 are enriched at transcriptional start sites and have been implicated in transcription. However, how these marks concertedly regulate transcription is not fully understood. Here, we developed a dual chemically inducible CRISPR/dCas9-based epigenome editing system that enables independent, temporal and transcription stage-specific modulation of H3K27ac and H3K4me3 at a specific gene locus. Stage-specific removal of H3K4me3 impaired RNA polymerase II recruitment, increased promoter-proximal pausing, reduced productive elongation, and accelerates mRNA decay via increased m6A deposition. Losing both H3K27ac and H3K4me3 rapidly abolished transcriptional activity, while preserving H3K4me3 without H3K27ac can partially sustain transcription. These findings revealed a functional hierarchy and interdependence between H3K27ac and H3K4me3 in different transcription stages and the established versatile tool will contribute to the functional dissection of the temporal dynamics of chromatin modifications in gene regulation.

genomics↗

A highly versatile real-time quantitative RT-PCR method and sampling strategies for the accurate detection of citrus yellow vein clearing virus

Citrus yellow vein clearing virus (CYVCV) is the causal agent of an emerging disease representing a potentially high-impact threat for citrus production. Despite remaining outside Europe for decades, CYVCV has now expanded towards two important European citrus producers, Italy and, more recently, Spain. The presence of this virus in the EPPO region represents a current threat with unpredictable and potentially devastating consequences for European citriculture. Therefore, urgent protective measures need to be taken to prevent CYVCV spread and minimize its impact. Diagnostics is a key measure in the management of viral diseases, highlighting the need for harmonized methods suitable for reliable routine detection of the currently known CYVCV diversity. In this study, an inclusive, efficient and highly sensitive real-time RT-qPCR for the detection of CYVCV in plant material and transmission vectors has been developed and validated according to EPPO standards. Moreover, the validated method has been successfully adapted to both PCR digital platforms, that allow high-sensitive absolute quantitative detection, essential in the diagnostics at low viral concentrations; and PCR portable tools, that can be applied in a real diagnostic context for on-site detection. This versatility combines standard validated performance, absolute sensitive quantitation and real on-site detection. The study has also addressed sampling strategies to support reliable molecular diagnostic performance. Our results represent an improvement in the detection of CYVCV to be applied in epidemiological studies and different real diagnostic contexts for the containment of this important citrus pathogen.

molecular biology↗

An optimized workflow for spatial transcriptomics across early development in Xenopus

How gene expression patterns change spatially as the embryo transitions from simple to complex structures remains a major developmental biology question. Recently developed imaging-based spatial transcriptomics (ST) enable mapping expression of multiple gene at a single-cell resolution. Although Xenopus is a key model in embryology there is no established ST pipeline, and commercially available techniques face many challenges (sample preparation, probe design, cell segmentation). Furthermore, the highly diverse cell shapes and sizes across developmental stages and between different tissues represent major hurdles to accurately defining cells. Here, we describe an optimized workflow for ST in blastula-to-tailbud-stage frog embryos using Merscope, commercial MERFISH (Multiplexed Error-Robust Fluorescence In Situ Hybridization) originally designed for standard mammalian tissues. With stringent quality control and tailored computational pipelines, we optimize this technology for robust, semi-quantitative profiling of spatial transcriptomic landscapes in non-mammalian embryos. Reliable tissue preservation and cell-segmentation enable high-resolution mapping of gene expression during the development of a complex multi-tissue organization. This versatile strategy applies broadly to various dynamic systems, from embryos of various model organisms to complex and heterogeneous organs in mammals. Summary statementThis Single-cell Spatial Transcriptomics pipeline and reference atlas in Xenopus - a model organism in embryology - overcome technical challenges and resolve dynamic changes in patterning during development.

developmental biology↗

Hex-MASP for Mapping the Whole-tissue Spatial Proteome and the Intra-brain Distribution of Monoclonal Antibodies

Whole-tissue spatial proteomics level provides critical insights into region-specific biological regulations but remains challenging. Previously, we introduced the Micro-scaffold Assisted Spatial Proteomics (MASP) concept for whole-tissue mapping. However, this prototype required substantial development in spatial resolution, practicality, and throughput for practical application. Here we present a next-generation MASP technique (hex-MASP) featuring i) a new design of hexagonal-micro-wells fabricated with optimized Projection Micro-Stereolithography (P{micro}SL) 3D-printing, achieving high spatial resolution, sampling robustness and mechanical strength for reproducibly compartmentalizing even tough tissues; ii) enhanced throughput/effectiveness in sample preparation and LC-MS analysis with high quantitative quality. Applied to mouse brain, hex-MASP for the first time achieved in-depth, whole-tissue mapping for >6,000 proteins in mouse brains, with high spatial accuracy and excellent data quality. The substantially improved resolution revealed critical regional details across the entire brain, that were not previously captured, enabling precise depiction of protein distribution heterogeneity. This technique enabled the discovery of many unreported regionally-enriched proteins across brain structures. We further applied hex-MASP to investigate the intra-brain distribution of intracerebroventricularly-dosed antibody therapeutics and related proteins, which to our knowledge, enabled whole tissue mapping of protein drugs for the first time and revealed novel mechanistic insights into antibody distribution and localized treatment effects. Hex-MASP represent a robust, scalable platform for whole-tissue spatial proteomics.

pharmacology and toxicology↗

Expanding P-NET, a multi-purpose biologically informed deep learning framework

We present expanded P-NET, a versatile frame-work for deep learning in computational biology based on P-NET, leveraging biological pathways for interpretable predictions. Our framework achieves competitive performance in genomic & transcriptomic prediction tasks. We demonstrate its stability and interpretability compared to traditional machine learning models. P-NET 2.0 incorporates gene and pathway information, providing valuable insights into complex biological processes. The framework is publicly available, enabling its application to various computational biology tasks.

bioinformatics↗

Decoding Single-Cell Omics of Perturbation Responses Using DeSCOPE

Deciphering cellular responses to genetic perturbations is fundamental to modeling gene regulatory networks and understanding mechanisms that change cellular phenotypes. However, current computational approaches often fail to outperform simple baseline models, highlighting a critical bottleneck in their generalizability and robustness. Here, we present DeSCOPE, a lightweight conditional variational autoencoder framework for predicting genetic perturbation responses spanning transcriptomic, epigenomic, and broader multi-modal landscapes. We systematically benchmarked DeSCOPE across diverse datasets under two challenging out-of-distribution settings: unseen genes and unseen cell types. DeSCOPE uniquely surpasses simple baselines in the unseen gene scenario, and achieves substantially improved performance for unseen cell types while requiring fine-tuning with far fewer perturbed genes. Finally, DeSCOPE demonstrates superior performance in predicting combinatorial multi-gene perturbations. Overall, DeSCOPE serves as a versatile multi-modal virtual cell model that can effectively guide the design of therapeutic targets that change cellular phenotypes. DeSCOPE is available at https://github.com/wanglabtongji/DeSCOPE.

bioinformatics↗

Task demands dynamically structure feature selection, routing, and integration in the human brain

AbstractFlexible visual categorization requires selecting task-relevant information from complex stimuli and transforming it through structured computations. Yet how task demands flexibly control these computations in the human brain remains unresolved. Dynamic faces provide a powerful test case, conveying stable identity through 3D shape and transient emotional expression through 4D movement. Using generative 4D face modelling, participant-specific MEG (N = 24), and information-theoretic analyses, we show that the brain implements a structured processing architecture. Task relevance first gates feature representations in occipital cortex, selectively sustaining relevant features while suppressing irrelevant ones. These features are then routed along pathway-specific channels--3D identity features to the ventral pathway and 4D emotion features to the lateral pathway. Finally, these inputs converge in temporal cortex, where identity and emotion features are synergistically integrated for learned identities. These results show how task demands dynamically structure feature selection, gating, routing, and integration, thereby constraining the computations that support flexible categorization.

neuroscience↗

Generation of Genetically Identical Mammalian Oocytes from Parthenogenetic Double-Haploid Embryonic Stem Cells

Generating genetically identical mammalian oocytes is challenging due to stochastic meiotic recombination. Here, we established parthenogenetic double-haploid embryonic stem cells (PG-DhESCs) possessing complete homozygosity. By employing blastocyst complementation in Prdm14-deficient embryos, we generated chimeric females that produced oocytes derived exclusively from these donor cells. Fertilization of these oocytes yielded viable, fertile, maternally semi-cloned (MSC) mice of both sexes. Although DNA methylation was largely restored during gametogenesis, subtle epigenetic defects correlated with increased body weight in MSC offspring. This study establishes a robust platform combining PG-DhESCs with blastocyst complementation to generate isogenic mammalian oocytes, overcoming traditional limitations in mammalian cloning.

developmental biology↗

Vagal dopaminergic afferents link interoception to trigeminal pain modulation

The vagus nerve conveys interoceptive information, yet how specific vagal sensory afferents regulate pain remains unclear. Here, we tested whether vagus nerve stimulation (VNS) modulates temporomandibular disorder (TMD)-related pain. In a mouse model of TMD, auricular VNS (aVNS) attenuated temporomandibular joint (TMJ) pain behaviors and suppressed sensitization of trigeminal nociceptors. We identified a subset of vagal sensory afferents with dopaminergic features that was sufficient to mediate these effects, as selective activation of these afferents recapitulated the analgesic actions of aVNS. These findings highlight an underappreciated peripheral interoceptive pathway and provide a mechanistic framework for targeted neuromodulation in chronic craniofacial pain.

neuroscience↗

Tract-explainable and underexplained synchrony play complementary roles in the functional organization of the brain

Macroscale functional connectivity emerges from a complex interplay between structural wiring and non-tract-mediated mechanisms. However, the intrinsic entanglement of these contributions obscures their specific roles in brain organization. Here, we introduce a computational modeling framework to disentangle functional synchrony into two fundamentally distinct components: tract-explainable and tract-underexplained synchrony. Validated across two large-scale human cohorts (n = 1214) and an independent marmoset dataset (n = 24), this dissociation reveals an evolutionarily conserved architectural principle. We show that tract-explainable synchrony aligns closely with structural connectomes to facilitate global integration. Conversely, tract-underexplained synchrony drives local modularity and is anchored by multiscale cortical similarity, encompassing microstructural, receptor, and transcriptomic profiles. Crucially, these components gradually dissociate from sensori-motor to higher-order association cortices, with the importance of tract-underexplained synchrony progressively increasing. Furthermore, the tract-underexplained synchrony exhibits greater individual variability and demonstrates a stronger association with individual cognitive performance. Ultimately, tract-based and non-tract-mediated mechanisms serve distinct yet complementary roles, jointly shaping a functional organization that balances conserved macroscopic stability with higher-order cognitive flexibility.

neuroscience↗

Efficient Reprogramming of the Epiblast Enables the Generation of Cloned Mice

Somatic cell nuclear transfer (SCNT) can generate viable mammals despite pervasive epigenetic abnormalities in cloned embryos, yet the mechanism underlying this paradox remains unclear. Here we show, using single-cell transcriptomics, that efficient reprogramming occurs exclusively in the epiblast (EPI), but the not primitive endoderm (PrE) of late mouse SCNT blastocysts. Integrating this with previous findings of trophectoderm (TE) aberration, we propose the EPI as the sole effectively reprogrammed lineage. By innovatively employing a Lego-like multi-lineage embryonic aggregation approach, where the extra-embryonic lineages were replaced with fertilization-derived counterparts, we demonstrated that SCNT-derived EPI inherently possesses full-term developmental potential nearly identical to that of fertilized EPI (20.5% vs. 21.8% birth rate), functionally confirming its effective reprogramming. Our study uncovers a lineage-specific asymmetric reprogramming mode where the EPI specifically achieves effective reprogramming, thereby constituting the deterministic basis for cloned animal generation. This work also provides a versatile strategy for investigating lineage potency and function.

developmental biology↗

Multiomic Spatial Imaging Assay (MSIA) -- A High-plex In Situ Detection Method for mRNAs, Proteins, and Protein-Protein Interactions using Manual And Semi-Automated Workflows

We report Multiomics Spatial Image Analysis (MSIA), a suite of technologies that include streamlined manual and semi-automated workflows to image 100s of RNAs from fresh frozen and formalin-fixed paraffin-embedded (FFPE) samples, contextualize RNAs with select protein markers including imaging synaptic protein interactions, a data analysis pipeline that includes corrections for chromatic aberration, algorithms for image stitching, deep learning models for image analysis (cell segmentation and RNA dot detection using hundreds of RNAscope images) from multiple stain-image cycles and proof of concept for a language model trained on extensive Parkinsons Disease (PD) literature. We used the language model to identify potential new biomarkers that were confirmed in MPTP-treated mouse model of PD. Furthermore, by incorporating more stain-image cycles alongside an additional fluorescent channel and advanced error-correcting decoding schemes, the MSIA workflow demonstrates the scalability to potentially quantify over 1,000 genes.

neuroscience↗

The Spatiotemporal Proteome Landscape of Aging: Structural determinants of age-sensitive proteome remodeling

Aging is marked by a decline in cellular functions accompanied by widespread changes in mRNA and protein abundance, yet whether aging broadly remodels subcellular protein localization and concentration--and why some proteins change while others remain stable--remains unclear. This gap matters because cellular function depends not only on expression levels but also on correct spatial organization. Using yeast replicative aging as a model, we built a robotic pipeline to enrich old cells from 5,661 strains, acquired 90 million single-cell 3D images, and applied machine learning to map proteome-wide changes in localization, concentration, and aggregation throughout aging. This age-resolved single-cell atlas uncovers widespread proteome remodeling and rewiring of protein interaction networks. Moreover, structural analysis reveals biophysical determinants of age-sensitive proteome remodeling across ages and species. Together, these results reveal a structure-encoded intrinsic principle underlying spatial proteome breakdown during aging and provide a resource to dissect mechanistic links among aging hallmarks.

systems biology↗

Sex-specific Genetic Regulatory Effects in Chickens

Sexual dimorphism is a defining vertebrate feature, yet its sex-specific molecular architecture remains poorly understood. Here we established a sex-balanced, uniformly reared chicken cohort to map this landscape, integrating individual whole-genome sequencing with 7,969 bulk and 779,380 single nucleus transcriptomes across 32 tissues from 280 birds. We identified 495,098 independent expression quantitative trait loci for 20,194 genes, including 10,937 loci modulated by cell-type composition. Notably, 340 genes were regulated by 449 loci in a sex-dependent manner, significantly enrichment in endocrine tissues like adipose and the adrenal gland. Furthermore, we fine-mapped 1,219 structural variants, demonstrating their unique roles to tissue- and sex-specific expression beyond SNPs. Ultimately, we showed the utility of these regulatory effects in elucidating the molecular basis of metabolism and complex traits in both chickens and humans. This comprehensive atlas of regulatory effects provides profound insights into the genomic and molecular basis of sexual dimorphism in vertebrates.

genomics↗