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Biology subjects

Zhang, R.

Publications and source records attributed to Zhang, R..

At least 181 records · Page 10Linked to original sources

Glycosylphosphatidylinositol biosynthesis restricts coronavirus infection via the regulation of LY6E

Coronaviruses, including SARS-CoV-2, rely on host factors for their replication and pathogenesis, while hosts deploy defense mechanisms to counteract viral infections. Although numerous host proviral factors have been identified, the landscape of host restriction factors and their underlying mechanisms remain less explored. Here, we conducted genome-wide CRISPR knockout screens using three distinct coronaviruses--SARS-CoV-2, HCoV-OC43 (a common cold human virus from the genus Betacoronavirus) and porcine epidemic diarrhea virus (Alphacoronavirus) to identify conserved host restriction factors. We identified glycosylphosphatidylinositol (GPI) biosynthesis as the pan-coronavirus host factor that restrict viral entry by disrupting spike protein-mediated membrane fusion at both endosomal and plasma membranes. GPI biosynthesis generates GPI moieties that covalently anchor proteins (GPI-anchored proteins [GPI-APs]) to the cell membrane, playing essential roles in various cellular processes. Through focused CRISPR knockout screens targeting 193 GPI-APs, we identified LY6E as the key downstream effector mediating the antiviral activity of the GPI biosynthesis pathway. These findings reveal a novel role for GPI biosynthesis as a conserved host defense mechanism against coronaviruses and highlight LY6E as a critical antiviral effector. This study provides new insights into virus-host interactions and the development of host-directed antiviral therapies.

microbiology↗

DAZAP2 functions as a pan-coronavirus restriction factor by inhibiting viral entry and genomic replication

The SARS-CoV-2 pandemic and the emergence of novel variants underscore the need to understand host-virus interactions and identify host factors that restrict viral infection. Here, we perform a genome-wide CRISPR knockout screen to identify host restriction factors for SARS-CoV-2, revealing DAZAP2 as a potent antiviral gene. DAZAP2, previously implicated in SARS-CoV-2 restriction, is found to inhibit viral entry by blocking virion fusion with both endolysosomal and plasma membranes. Additionally, DAZAP2 suppresses genomic RNA replication without affecting the primary translation of viral replicases. We demonstrate that DAZAP2 functions as a pan-coronavirus restriction factor across four genera of coronaviruses. Importantly, knockout of DAZAP2 enhances SARS-CoV-2 infection in mouse models and in human primary airway epithelial cells, confirming its physiological relevance. Mechanistically, antiviral activity of DAZAP2 appears to be indirect, potentially through the regulation of host gene expression, as it primarily localizes to the nucleus. Our findings provide new insights into the host defense system against coronaviruses and highlight DAZAP2 as a potential target for host-directed antiviral therapies. IMPORTANCEDuring viral infection, the host defense response is mediated by a variety of host factors through distinct mechanisms that have yet to be fully elucidated. Although DAZAP2 was previously implicated in SARS-CoV-2 restriction, its mechanisms of action and in vivo relevance remain unclear. In this study, we identify the DAZAP2 as a potent pan-coronavirus restriction factor that inhibits viral infection through dual mechanisms: blocking virion fusion with both endolysosomal and plasma membranes, and suppressing genomic RNA replication. We confirm its physiological relevance in host defense using mouse models and primary cell cultures. This study advances our understanding of host-pathogen interactions. Targeting DAZAP2 or its regulatory pathways could provide a new approach to enhance host defense against current and future coronavirus threats.

microbiology↗

B cell subsets have different capacities for phagocytosis and subsequent presentation of antigen to cognate T cells

B cells have been shown to be phagocytic under some circumstances. However, the phagocytic capacity of different B cell subsets and how this is linked to Antigen (Ag) presentation or other functions has not been characterized. To address this, we developed 2 {micro}m phagocytic Ag conjugated bead targets that target phagocytic pathways including the BCR, scavenger, Fc, and complement receptors to study potential pathways by which B cells phagocytose both cognate and non-cognate Ags. We found that while follicular B2 (Fo B), marginal zone, and B1 B cells are highly phagocytic of BCR-engaging targets through their BCR, only peritoneal cavity B1 cells could uptake non-cognate Ag-coated beads or bacteria. Despite this, B1 cells were not effective at presenting Ag to activate cognate T cells or at killing phagocytosed bacteria. Finally, analysis of scRNA-seq data revealed that these differences in phagocytic capacity could not be explained by differential expression of relevant phagocytic receptors, implying that there is likely some form of regulation in place preventing non-cognate Ag uptake by Fo B cells. Our work will help contribute to a better understanding of non-classical Ag uptake mechanisms employed by B cells and their relevance to inflammation.

immunology↗

YTHDF3 promotes the progression of gastric cancer by activating Wnt/β-catenin signaling pathway via targeting NEK7

Gastric cancer (GC) is a widespread and deadly malignancy among global digestive tract tumors, alarmingly ranked the fifth most common cancer in terms of incidence and mortality. This study used immunohistochemistry and RT-qPCR to reveal a significant upregulation of YTHDF3 expression in GC tissues compared with that of adjacent normal tissues. This increased expression of YTHDF3 was closely associated with the incidence of lymph node metastasis and the progression to more advanced TNM stages. In vitro experiments demonstrated that YTHDF3 was crucial in promoting the aggressive characteristics of GC cells by enhancing their ability to proliferate, migrate, and invade, while simultaneously inhibiting apoptosis. The role of YTHDF3 in the progression of GC was further confirmed using the BALB/c nude mice subcutaneous tumor model, which showed a slowed tumor growth after YTHDF3 knockdown. This study further confirmed through Co-IF RIP-qPCR, western blotting, and rescue studies that YTHDF3 promotes GC progression by targeting NEK7 to regulate the Wnt/{beta}-catenin signaling pathway. In conclusion, our pivotal findings highlight the YTHDF3/NEK7/Wnt/{beta}-catenin axis as a promising and accessible therapeutic target for the development of new treatments aimed at improving clinical outcome of patients with GC.

cancer biology↗

Toti: an integrated multi-omics database to decipher the epigenetic regulation of gene expression in totipotent stem cells

Totipotent cells (TSCs), the origin of mammalian life and foundation to early mammalian embryogenesis, are characterized by the highest differentiation capacity and extensive developmental potential. However, none of the existing embryonic databases have provided epigenetic and transcriptomic resources on totipotency, greatly limiting our understanding of the mechanisms governing the establishment and exit of totipotency. Here, we present Toti, a pioneering multi-omics database exclusively developed for totipotency, covering in vivo, in vitro and genome-edited human and mouse embryonic TSCs, TSC-like cells, pluripotent cells (PSCs), and embryos spanning preimplantation stages, with a total of 8,265 samples. Toti facilitates an in-depth exploration of the molecular mechanisms underlying totipotency by offering Search, Browse and Analysis modules available at http://toti.zju.edu.cn/.

developmental biology↗

Modification of Non-photochemical Quenching Pathways in the C4 Model Plant Setaria viridis Revealed Shared and Unique Photoprotection Mechanisms as Compared to C3 Plants

Light is essential for photosynthesis; however, excess light can increase the accumulation of photoinhibitory reactive oxygen species that reduce photosynthetic efficiency. Plants have evolved photoprotective non-photochemical quenching (NPQ) pathways to dissipate excess light energy. In tobacco and soybean (C3 plants), overexpression of three NPQ genes, violaxanthin de-epoxidase (VDE), Photosystem II Subunit S (PsbS), and zeaxanthin epoxidase (ZEP), hereafter VPZ, resulted in faster NPQ induction and relaxation kinetics, and increased crop yields in field conditions. NPQ is well-studied in C3 plants; however, NPQ and the translatability of the VPZ approach in C4 plants is poorly understood. The green foxtail Setaria viridis is an excellent model to study photosynthesis and photoprotection in C4 plants. To understand the regulation of NPQ and photosynthesis in C4 plants, we performed transient overexpression in Setaria protoplasts and generated (and employed) stable transgenic Setaria plants overexpressing one of the three Arabidopsis NPQ genes or all three NPQ genes (AtVPZ lines). Overexpressing (OE) AtVDE and AtZEP in Setaria produced similar results as in C3 plants, with increased or reduced zeaxanthin (thus NPQ), respectively. However, overexpressing AtPsbS appeared to be challenging in Setaria, with largely reduced NPQ in protoplasts and under-represented homozygous AtPsbS-OE lines, potentially due to competitive and tight heterodimerization of AtPsbS and SvPsbS proteins. Furthermore, Setaria AtVPZ lines had increased zeaxanthin, faster NPQ induction, higher NPQ level, but slower NPQ relaxation. Despite this, AtVPZ lines had improved growth as compared to wildtype under several conditions, especially high temperatures, which is not related to the faster relaxation of NPQ but may be attributable to increased zeaxanthin and NPQ in C4 plants. Our results identified shared and unique characteristics of the NPQ pathway in C4 model Setaria as compared to C3 plants and provide insights to improve C4 crop yields under fluctuating environmental conditions.

plant biology↗

Exosomal miR-145-5p promotes apoptosis of renal tubule epithelial cells through the JNK signalling pathway

Acute kidney injury (AKI) is the most prevalent extrapulmonary organ failure observed in patients with acute respiratory distress syndrome (ARDS). However, the underlying mechanisms leading to AKI in ARDS remain unclear. Exosomes facilitate intercellular and inter-organ communication via exosomal microRNAs (miRNAs), which potentially contribute to the crosstalk between the lung and kidney in ARDS. Therefore, the purposes of our study were to investigate the involvement of exosomal miRNAs in the development of AKI in ARDS. In current study, Sprague-Dawley rats were induced to develop ARDS via hydrochloric acid aspiration. Nanoparticle tracking analysis, Transmission electron microscopy and western blotting were conducted to analyse the exosomes. Quantitative reverse transcription-polymerase chain reaction and in situ hybridisation showed elevated expression level of miR-145-5p in the circulating exosomes and lung tissue of ARDS rats. Overexpression of miR-145-5p disrupted the proteomic profile of renal proximal tubule epithelial cells, leading to impacts on proteins associated with various biological processes, including apoptosis. We further demonstrate that miR-145-5p overexpression enhanced JNK phosphorylation by directly repressing RBM3 expression and promoted cell apoptosis. In vivo, administration of agomiR-145-5p injection via intravenous route, which subsequently induced renal tubular cell apoptosis. These findings have revealed that miR-145-5p may serve as a novel mediator for the apoptosis of renal cell in the context of ARDS.

cell biology↗

Systematic Identification of Microtubule Inner Proteins Reveals JPT2 as a Key Regulator of Lumen Microenvironment and Drug Sensitivity

Microtubules are primarily studied for the interactions of proteins that bind to their outer surfaces and ends, while the regulatory mechanisms within the microtubule lumen, particularly in singlet microtubules critical for essential cellular processes, remain largely unexplored. Our study provides the first systematic identification of key regulatory proteins within the single microtubule lumen. Using proximity-dependent biotin identification (Bio-ID) coupled with mass spectrometry, we identified candidate microtubule inner proteins (MIPs), including Jupiter microtubule-associated homolog 2 (JPT2). JPT2 binds directly to microtubules and specifically localizes within the lumen, where it modulates the luminal environment by inhibiting acetylase MEC17 and independently affects the binding and efficacy of Paclitaxel. Furthermore, our screening identified additional MIPs that influence cellular sensitivity to Paclitaxel, indicating a link between luminal regulation and drug responsiveness. These discoveries reveal JPT2s critical role in singlet microtubule regulation and suggest new therapeutic targets for enhancing cancer drug sensitivity.

cell biology↗

APMAT analysis reveals the association between CD8 T cell receptors, cognate antigen, and T cell phenotype and persistence

Elucidating the relationships between a class I peptide antigen, a CD8 T cell receptor (TCR) specific to that antigen, and the T cell phenotype that emerges following antigen stimulation, remains a mostly unsolved problem, largely due to the lack of large data sets that can be mined to resolve such relationships. Here, we describe Antigen-TCR Pairing and Multiomic Analysis of T-cells (APMAT), an integrated experimental-computational framework designed for the high-throughput capture and analysis of CD8 T cells, with paired antigen, TCR sequence, and single-cell transcriptome. Starting with 951 putative antigens representing a comprehensive survey of the SARS-CoV-2 viral proteome, we utilize APMAT for the capture and single cell analysis of CD8 T cells from 62 HLA A*02:01 COVID-19 participants. We leverage this unique, comprehensive dataset to integrate with peptide antigen properties, TCR CDR3 sequences, and T cell phenotypes to show that distinct physicochemical features of the antigen-TCR pairs strongly associate with both T cell phenotype and T cell persistence. This analysis suggests that CD8+ T cell phenotype following antigen stimulation is at least partially deterministic, rather than the result of stochastic biological properties.

immunology↗

The single amino acid change of R516K enables efficient generation of vesicular stomatitis virus-based Crimean-Congo hemorrhagic fever reporter virus

Crimean-Congo hemorrhagic fever virus (CCHFV) is a medically important tick-borne virus, causing severe hemorrhagic diseases in humans. There is no approved vaccines and therapeutics for CCHFV infection. The study of CCHFV authentic virus requires biosafety level 3 facilities, hindering the research and development of antivirals. Here we report the generation of a recombinant vesicular stomatitis virus (VSV) bearing both CCHFV glycoprotein precursor (GPC) and EGFP reporter (rVSV-CCHFV-GFP). We also find that the acquisition of an unexpected single R516K mutation in the GPC protein enables the packaging of high-titer pseudotyped particles. The replication-competent rVSV-CCHFV-GFP reporter virus resembles the entry properties of authentic virus and allows for rapid assessment of susceptible cell lines, neutralizing antibodies, and host entry factors such as heparan sulfate in fluorescence-based assays. This study provides valuable strategy for packaging of high-titer CCHFV pseudovirus, and the tool generated here can be served for the identification and evaluation of countermeasures against the cell entry of CCHFV.

microbiology↗

Astrocyte-derived extracellular matrix proteins regulate synapse remodeling in stress-induced depression

Major depressive disorder (MDD) is a common mood condition affecting multiple brain regions and cell types. Changes in astrocyte function contribute to depressive-like behaviors. However, while neuronal mechanisms driving MDD have been studied in some detail, molecular mechanisms by which astrocytes promote depression have not been extensively explored. To uncover astrocyte contributions to MDD, we subjected male mice to chronic social defeat stress precipitated by encounters with a dominant male. Animals exposed to this treatment exhibit symptoms indicative of MDD, including reduced social interactions, anxiety, despair, and anhedonia. We then measured astrocyte translating mRNA expression changes in mice that underwent chronic social defeat and control animals using ribosome affinity purification. Bioinformatic analyses reveal significant alterations in the prefrontal cortex (PFC), consistent with previous studies implicating this brain region in MDD. Expression of genes encoding extracellular matrix (ECM) proteins, cell-cell interaction proteins, and proteins controlling glutamatergic synaptic function are significantly altered. These changes correlate with perturbation of glutamatergic transmission, measured by electrophysiology, and increased synaptic cleft size. Among ECM genes, increased expression of mRNA encoding the synaptic remodeling protein secreted protein acidic and rich in cysteine (Sparc) correlates the most with the depressive phenotype. Furthermore, presence of SPARC and other ECM proteins in synaptosomes is also increased and overexpressing Sparc in PFC partially alleviates stress symptoms. Our results raise the possibility that increased expression of Sparc may be a natural protective mechanism against stress-induced synaptic dysfunction in depression.

neuroscience↗

Dissociable neurofunctional and molecular characterizations of reward and punishment sensitivity

While the hyper-and hypo-reward or punishment sensitivities (RS, PS) have received considerable attention as prominent transdiagnostic features of psychopathology, the lack of an overarching neurobiological characterization currently limits their early identifications and neuromodulations. Here we combined microarray data from the Allen Human Brain Atlas with a multimodal fMRI approach to uncover the neurobiological signatures of RS and PS in a discovery-replication design (N=655 participants). Both RS and PS were mapped separately in the brain, with the intrinsic functional connectome in the fronto-striatal network encoding reward responsiveness, while the fronto-insular system was particularly engaged in punishment sensitivity. This dissociable functional connectome patterns related to RS and PS were also specific in differentiating decisions driven by social or monetary reward and punishment motivations. Further imaging transcriptomic analyses revealed that functional connectome variations for RS and PS were associated with topography of specific gene sets enriched in ontological pathways, including synaptic transmission, dopaminergic metabolism, immune response and stress adaptation. On the neurotransmitter level, the serotonin neuromodulator was identified as a pivotal hub regulating the intrinsic functional connectome patterns of RS and PS, with this process critically dependent on its interactions with dopaminergic, opioid and GABAergic systems. Overall, these findings indicate dissociable neural connectome mapping of RS and PS and highlight their linkage with transcriptomic profiles, which may offer valuable insights into the treatment evaluation for symptomatology relevant to reward/punishment processing deficits.

neuroscience↗

Systematic Benchmarking of High-Throughput Subcellular Spatial Transcriptomics Platforms

Recent advancements in spatial transcriptomics technologies have significantly enhanced resolution and throughput, underscoring an urgent need for systematic benchmarking. To address this, we collected clinical samples from three cancer types - colon adenocarcinoma, hepatocellular carcinoma, and ovarian cancer - and generated serial tissue sections for systematic evaluation. Using these uniformly processed samples, we generated spatial transcriptomics data across five high-throughput platforms with subcellular resolution: Stereo-seq v1.3, Visium HD FFPE, Visium HD FF, CosMx 6K, and Xenium 5K. To establish ground truth datasets, we profiled proteins from adjacent tissue sections corresponding to all five platforms using CODEX and performed single-cell RNA sequencing on the same samples. Leveraging manual cell segmentation and detailed annotations, we systematically assessed each platforms performance across key metrics, including capture sensitivity, specificity, diffusion control, cell segmentation, cell annotation, spatial clustering, and transcript-protein alignment with adjacent CODEX. The uniformly generated, processed, and annotated multi-omics dataset is valuable for advancing computational method development and biological discoveries. The dataset is accessible via SPATCH, a user-friendly web server for visualization and download (http://spatch.pku-genomics.org/).

genomics↗

Dynamic Grouping of Ongoing Activity in V1 Hypercolumns

Neurons spontaneous activity provides rich information about the brain. A single neurons activity has close relationships with the local network. In order to understand such relationships, we studied the spontaneous activity of thousands of neurons in macaque V1 and V2 with two-photon calcium imaging. In V1, the ongoing activity was dominated by global fluctuations in which the activity of majority of neurons were correlated. Neurons activity also relied on their relative locations within the local functional architectures, including ocular dominance, orientation, and color maps. Neurons with similar preferences dynamically grouped into co-activating ensembles and exhibited spatial patterns resembling the local functional maps. Different ensembles had different strengths and frequencies. This observation was consistent across all hypercolumn-sized V1 locations we examined. In V2, different imaging sites had different orientation and color features. However, the spontaneous activity in the sampled regions also correlated with the underlying functional architectures. These results indicate that functional architectures play an essential role in influencing neurons spontaneous activity, and can be explained by a network model that integrates diverse horizontal connections among similar functional domains.

neuroscience↗

OPUS-GO: An interpretable protein/RNA sequence annotation framework based on biological language model

Accurate annotation of protein and RNA sequences is essential for understanding their structural and functional attributes. However, due to the relative ease of obtaining whole sequence-level annotations compared to residue-level annotations, existing biological language model (BLM)-based methods often prioritize enhancing sequence-level classification accuracy while neglecting residue-level interpretability. To address this, we introduce OPUS-GO, which exclusively utilizes sequence-level annotations to provide both sequence-level and residue-level classification results. In other words, OPUS-GO not only provides the sequence-level annotations but also offers the rationale behind these predictions by pinpointing their corresponding most critical residues within the sequence. Our results show that, by leveraging features derived from BLMs and our modified Multiple Instance Learning (MIL) strategy, OPUS-GO exhibits superior sequence-level classification accuracy compared to baseline methods in most downstream tasks. Furthermore, OPUS-GO demonstrates robust interpretability by accurately identifying the residues associated with the corresponding labels. Additionally, the OPUS-GO framework can be seamlessly integrated into any language model, enhancing both accuracy and interpretability for their downstream tasks.

bioinformatics↗

Preferential Release of microRNAs via Extracellular Vesicles is Associated with Ductal Carcinoma In Situ to Invasive Breast Cancer Progression

Ductal carcinoma in situ (DCIS) is a benign "pre-cancer" that increases the risk of invasive breast cancer (IBC). Not all DCIS progress to IBC, and the primary factors driving progression remain unclear. Small extracellular vesicles (sEVs) or exosomes are known to play a role in advanced cancers, but their involvement in DCIS is poorly understood. This study examined the role of sEVs and their RNA content in DCIS progression. Rab27A, which regulates exosome release, is elevated in DCIS and IBC tissues compared with normal breast tissues. Inhibition of sEV release via Rab27A knockdown alters pro-invasive pathways and reduces invasion in a DCIS mouse model. Using the isogenic MCF10 breast cancer progression series, we found a significant increase in microRNAs (miRNAs) in sEVs from normal to malignant states, with the highest number of differentially expressed miRNAs in IBC sEVs compared with DCIS sEVs. In vivo, DCIS invasive progression elevated circulating sEV miRNA levels, which decreased upon Rab27A knockdown. Re-expression of miR-205, preferentially loaded into IBC sEVs, reduced proliferation, invasion, and EMT marker expression in DCIS cells. Combined Rab27A knockdown and miR-205 expression repressed TGF-{beta} signaling, activated p38, and induced cell cycle arrest and cell death. These findings illustrate that sEVs and their miRNAs promote DCIS progression, and the reintroduction of miR-205 in DCIS cells can inhibit invasive progression.

cancer biology↗

Deconstruction of a memory engram reveals distinct ensembles recruited at learning

How are associative memories formed? Which cells represent a memory, and when are they engaged? By visualizing and tagging cells based on their calcium influx with unparalleled temporal precision, we identified non-overlapping dorsal CA1 neuronal ensembles that are differentially active during associative fear memory acquisition. We dissected the acquisition experience into periods during which salient stimuli were presented or certain mouse behaviors occurred and found that cells associated with specific acquisition periods are sufficient alone to drive memory expression and contribute to fear engram formation. This study delineated the different identities of the cell ensembles active during learning, and revealed, for the first time, which ones form the core engram and are essential for memory formation and recall.

neuroscience↗

Mycobacterium tuberculosis CrgA Forms a Dimeric Structure with Its Transmembrane Domain Sandwiched between Cytoplasmic and Periplasmic β-Sheets, Enabling Multiple Interactions with Other Divisome Proteins

CrgA is a key transmembrane (TM) protein in the cell division process of Mycobacterium tuberculosis (Mtb), the pathogen responsible for tuberculosis. While many of the Mtb divisome proteins have been identified, their structures and interactions remain largely unknown. Previous studies of CrgA using oriented-sample solid-state NMR have defined the tilt and rotation of the TM helices, but the cytoplasmic and periplasmic domains and even the oligomeric state were uncharacterized. Here, combining oriented-sample and magic-angle spinning solid-state NMR spectra, we solved the full-length structure of CrgA. The structure features a dimer with a TM domain sandwiched between a cytoplasmic {beta}-sheet and a periplasmic {beta}-sheet. The {beta}-sheets stabilize dimerization, which in turn increases CrgAs ability to participate in multiple protein interactions. Within the membrane, CrgA binds FtsQ, CwsA, PbpA, FtsI, and MmPL3 via its TM helices; in the cytoplasm, Lys23 and Lys25 project outward from the {beta}-sheet to interact with acidic residues of FtsQ and FtsZ. The structural determination of CrgA thus provides significant insights into its roles in recruiting other divisome proteins and stabilizing their complexes for Mtb cell wall synthesis and polar growth.

biophysics↗