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Biology subjects

Zhong, Y.

Publications and source records attributed to Zhong, Y..

At least 91 records · Page 5Linked to original sources

Spatially resolved molecular and cellular atlas of the mouse brain

A comprehensive atlas of genes, cell types, and their spatial distribution across a whole mammalian brain is fundamental for understanding function of the brain. Here, using snRNA-seq and Stereo-seq techniques, we generated a mouse brain atlas with spatial information for 308 cell clusters with single-cell resolution involving over 6 million cells as well as for 29,655 genes. We have identified new astrocyte clusters, and demonstrated that distinct cell clusters exhibit preference for cortical subregions. In addition, we identified 155 genes exhibiting regional specificity in the brainstem, and 513 long non-coding RNA exhibited regional specificity in the adult brain. Parcellation of brain regions based on spatial transcriptomic information showed large overlap with that by traditional method. Furthermore, we have uncovered 411 transcription factor regulons with spatiotemporal specificity during development. Thus, our study has discovered genes and regulon with spatiotemporal specificity, and provided a high-resolution spatial transcriptomic atlas of the mouse brain.

neuroscience↗

Revisiting the Kuleshov effect with authentic films: A behavioral and fMRI study

As a fundamental film theory, montage theory posits that film editing significantly influences the viewers perception. The Kuleshov effect, a central concept in montage theory, proposes that the emotional interpretation of neutral facial expressions is influenced by the accompanying emotional scene in a face-scene-face sequence. However, concerns persist regarding the validity of previous studies, often employing inauthentic film materials like static images, leaving the question of its existence in authentic films unanswered. This study addresses these concerns by utilizing authentic films in two experiments. In Experiment 1, multiple film clips were captured under the guidance of a professional film director and seamlessly integrated into authentic film sequences. A total of 59 participants viewed these face-scene-face film sequences and were tasked with rating the valence of neutral faces. The findings revealed that the interpretation of emotion in neutral faces is significantly influenced by the accompanying fearful or happy scene, eliciting perceptions of negative or positive emotion from the neutral face. These results affirm the existence of the Kuleshov effect within authentic film sequences. In Experiment 2, 31 participants engaged in a similar task under functional magnetic resonance imaging (fMRI). The results revealed neural correlates supporting the existence of the Kuleshov effect at a neural level. These correlates include the cuneus, precuneus, hippocampus, parahippocampal gyrus, post cingulate gyrus, orbitofrontal cortex, fusiform gyrus, and insula. These findings also underscore the contextual framing inherent in the Kuleshov effect. By seamlessly integrating film theory and cognitive neuroscience experiments, this comprehensive study provides robust evidence supporting the existence of the Kuleshov effect. It significantly enhances our understanding of film editing and its profound impact on viewers perception.

neuroscience↗

Cell segmentation and gene imputation for imaging-based spatial transcriptomics

Imaging-based spatial transcriptomics technologies are revolutionary tools for biomedical investigation, but the power is currently limited by small number of measured genes and tricky cell segmentation. Here we introduce RedeFISH to simultaneously conduct cell segmentation and gene imputation for imaging-based spatial transcriptomics with the aid of single-cell RNA sequencing data. Extensive benchmarking across various spatial platforms and tissue types shows the validity and power of the cell-segmented, whole-transcriptome spatial data generated by RedeFISH.

bioinformatics↗

Interrogation of inter-layer neuronal connectivity via cross-region all-optical physiology with high temporal resolution

The interrogation of functional neural circuits is crucial for uncovering how the brain works during diverse behaviors. Multi-plane neurophysiological measurement systems with high temporal resolution are indispensable, especially for dissecting inter-layer functional connectivity. Here, we develop a cross-layer all-optical physiology system (CLAOP) that enables the simultaneous recording and manipulation of single-neuron activities in multiple neuronal layers, with axial intervals as large as 530 m, at high temporal resolutions. Based on spatiotemporal multiplexing, our system enables all-optical analysis with a high frame rate up to 396 Hz and minimal time delay in inter-layer imaging and photostimulation, in both the mouse cortex and hippocampus in vivo. Combined with behavioral experiments, CLAOP provides all-optical evidence linking behavioral responses to neuronal connectivity in the primary visual cortex (V1) of live mice. Furthermore, we demonstrate that CLAOP can perturb the activity response of inter-layer cortical neurons to sensory stimuli according to their functional signatures. Overall, CLAOP provides an all-optical approach for mapping inter-layer connectivity at the single-neuron level and for modifying neuronal responses in behaving animals.

neuroscience↗

Co-occurrence of ST412 Klebsiella pneumoniae isolates with hypermucoviscous and no-mucoviscous phenotypes in a short-term hospitalized patient

Hypermucoviscosity(HMV) is a phenotype that is commonly associated with hypervirulence in Klebsiella pneumoniae. The factors that contribute to the emergence of HMV subpopulations remain unclear. In this study, eight K. pneumoniae strains were recovered from an inpatient who were hospitalized for 20 days. Three of the isolates exhibited a non-HMV phenotype, which was concomitant with increased biofilm formation and higher siderophore secretion than the other five HMV isolates. All eight isolates were highly susceptible to serum killing, albeit HMV strains were remarkably more infective than non-HMV counterparts in a mouse model of infection. Whole genome sequencing(WGS) showed that the eight isolates belonged to the K57-ST412 lineage. Average nucleotide identity(ANI) analysis indicated that eight isolates share 99.96% to 99.99% similarity and were confirmed to be the same clone. Through comparative genomics analysis, 12 non-synonymous mutations were found among these isolates, seven of which in the non-HMV variants, including rmpA(R96G) and wbap (S435R), which are assumed to be associated with the non-HMV phenotype. The mutations manB(G440L), dmsB(R193W) and tkt(A643N) occurred in HMV isolates only. RNA-Seq and RT-qPCR revealed transcripts of genes involved in transporter activity, carbohydrate metabolism and energy metabolism, including cysK, paaF, vasD, celC and fruA, to be significantly dysregulated in the non-HMV strain K201060 compared to the HMV strain K201059, suggesting a participation in HMV phenotype development. This study suggests that co-occurrence of HMV and non-HMV phenotypes in the same clonal population may be mediated by mutational mechanisms as well as by certain genes involved in transport and central metabolism. ImportanceK. pneumoniae with a hypermucoviscosity(HMV) phenotype is a community-acquired pathogen that associated with increased invasiveness and pathogenicity, and underlying diseases are the most common comorbid risk factors inducing metastatic complications. HMV was earlier attributed to the overproduction of capsular polysaccharide, and more data point to the possibility of several causes contribute to this bacterial phenotype. Here, we describe a unique event in which the same clonal population showed both HMV and non-HMV characteristics. Studies have demonstrated that this process is influenced by mutational processes and genes related to transport and central metabolism. These finding provide fresh insight into the mechanisms between behind co-occurrence of HMV and non-HMV phenotypes in monoclonal populations as well as potentially being critical in developing strategies to control the further spread of HMV K. pneumoniae.

microbiology↗

Diffusion model of delipidation in biological sample clearing

Biological sample clearing techniques are a potent tool for three-dimensional biological imaging, among which delipidation is an essential step in achieving high-quality biological sample transparency. Detergents and organic solvents can both be used for lipids removal. The former has been extensively investigated in biological sample clearing, while the delipidation process based on organic solvents remains to be further elucidated. Recently, organic solvents also served as a delipidation reagent in aqueous-based clearing methods and exhibited very fast clearing speed. To explain the high efficiency of organic solvents, we described the delipidation process of both detergents and organic solvents with a simple diffusion model, we proposed a possible mechanism of the delipidation process of water-miscible polar organic solvents based on the clearing results of brain samples. Both our results and model revealed that polar or non-polar organic solvents with a certain molecular structure could achieve a much faster clearing speed than detergents which could be a guide for establishing a rapid clearing protocol for biological samples with large volumes.

neuroscience↗

Enhancing anti-gastrointestinal cancer activities of CLDN18.2 CAR-T armored with novel synthetic NKG2D receptors Containing DAP10 and DAP12 signaling domains.

Chimeric antigen receptor (CAR) T therapies have shown remarkable efficacy in hematopoietic malignancies, but their therapeutic benefits in solid tumors have been limited due to heterogeneities in both antigen types and their expression levels on tumor cells. NK group 2 member D ligands (NKG2DLs) are extensively expressed on various tumors and absent on normal tissues, making them a promising target for cellular immunotherapy. DAP10 and DAP12 function as adaptor proteins in NK cells to transduce activating signals, and recent studies have revealed DAP10 and DAP12s additional role as a co-stimulatory signal in T cells. Our pre-clinical data showed that CAR-T targeting CLDN18.2 is highly effective in gastrointestinal (GI) cancers, but the heterogeneous expression of CLDN18.2 poses a treatment challenge. To complement this antigen deficiency, we demonstrated that NKG2DLs were extensively expressed in GI tumor tissues and formed an ideal dual target. Here, we reported a CLDN18.2 CAR design armored with synthetic NKG2D receptors (SNR) containing DAP10 and DAP12 signaling domains. This novel CAR-T showed improved cytotoxicity against tumor cells with heterogeneous expression of CLDN18.2. The possible underlined mechanism is that SNR promotes CAR-T memory formation and reduces their exhaustion, while also enhancing their expansion and ability to infiltrate immune-excluded tumors in vivo. Taken together, SNR with DAP10/12 signaling and their synergistic involvement, increased CAR-T function and overcame the antigen deficiency, providing a novel treatment modality for solid GI tumor.

immunology↗

Interpretable modeling of time-resolved single-cell gene-protein expression using CrossmodalNet

Cell-surface proteins play a critical role in cell function and are primary targets for therapeutics. CITE-seq is a single-cell technique that enables simultaneous measurement of gene and surface protein expression. It is powerful but costly and technically challenging. Computational methods have been developed to predict surface protein expression using gene expression information such as from single-cell RNA sequencing (scRNA-seq) data. Existing methods however are computationally demanding and lack the interpretability to reveal underlying biological processes. We propose CrossmodalNet, an interpretable machine learning model, to predict surface protein expression from scRNA-seq data. Our model with a customized adaptive loss accurately predicts surface protein abundances. When samples from multiple time points are given, our model encodes temporal information into an easy-to-interpret time embedding to make prediction in a time point-specific manner able to uncover noise-free causal gene-protein relationships. Using two publicly available time-resolved CITE-seq data sets, we validate the performance of our model by comparing it to benchmarking methods and evaluate its interpretability. Together, we show our method accurately and interpretably profiles surface protein expression using scRNA-seq data, thereby expanding the capacity of CITE-seq experiments for investigating molecular mechanisms involving surface proteins.

bioinformatics↗

memo-eQTL: DNA methylation modulated genetic variant effect on gene transcriptional regulation

Expression quantitative trait locus (eQTL) analysis has become an important tool in understanding the link between genetic variants and gene expression, ultimately helping to bridge the gap between risk SNPs and associated diseases. Recently, we identified and validated a specific case where the methylation of a CpG site can affect the relationship between the genetic variant and gene expression. To systematically evaluate this regulatory mechanism, we developed an extended eQTL mapping method named DNA methylation modulated eQTL (memo-eQTL). We performed memo-eQTL mapping in 128 normal prostate samples and discovered 1,731 memo-eQTLs, a vast majority of which have not been reported as eQTLs. We found that the methylation of the memo-eQTL CpG sites can either enhance or insulate the interaction between SNP and Gene expression by altering CTCF-based chromatin 3D structure. This study demonstrated the prevalence of memo-eQTLs, which can enable the identification of novel causal genes for traits or diseases associated with genetic variations.

bioinformatics↗

INHIBITORY EFFECTS OF GLUCOCORTICOID ON IMMUNOCYTES

Glucocorticoids (GCs) are efficacious agents for reducing inflammation and suppressing immune responses, exerting various effects on immune cells through the intracellular glucocorticoid receptor (GR), and impacting both innate and adaptive immunity. In the context of COVID-19, glucocorticoids are often used to treat severe cases of patients by reducing inflammation, suppressing immune responses, and ameliorating the severity of COVID-19. However, the precise inhibitory effects on immune cells have yet to be comprehensively delineated. In this study, we extensively examined the inhibitory effects of treating Balb/c mice with dexamethasone (DEX) on lymphoid and myeloid cells. We observed that high doses of DEX treatment resulted in a reduction in the number of immunocytes and an attenuation of their activity. Particularly noteworthy, macrophages, DC cells, and monocytes were diminished by approximately 90% following high doses of DEX, while B cells experienced a reduction of about 70% and CD3 T cells were less affected. Furthermore, our findings demonstrated that DEX induces the inhibition of immune cells by engaging in high-affinity binding to GR. Consequently, we conclude that DEX treatments affect a broad range of immune cells, encompassing both lymphoid and myeloid cells, through depletion or the down-regulation of immune function, potentially acting via the GR signaling pathway. These findings may enhance the clinical applicability of DEX in achieving transient immune deficiency.

immunology↗

Sequencing of N6-methyl-deoxyadenosine at single-base resolution across the mammalian genome

While DNA N6-methyl-deoxyadenosine (6mA) is abundant in bacteria and protists, its presence and function in mammalian genomes have been less clear. We present Direct-Read 6mA sequencing (DR-6mA-seq), an antibody-independent method to measure 6mA at base-resolution with high sensitivity. DR-6mA-seq employs a unique mutation-based strategy to reveal 6mA sites as misincorporation signatures without any chemical or enzymatic modulation of 6mA. We validated DR-6mA-seq through successful mapping of the well-characterized G(6mA)TC motif in the E. coli DNA and identified 6mA sites in the mammalian mitochondrial DNA. As expected, when applying DR-6mA-seq to mammalian systems, we found that genomic DNA (gDNA) 6mA abundance is in general low in most mammalian tissues and cells; however, we did observe distinct gDNA 6mA sites in mouse testis and glioblastoma cells. DR-6mA-seq provides an enabling tool to detect 6mA at single-base resolution with high sensitivity for a comprehensive understanding of DNA 6mA in eukaryotes.

genetics↗

Spatial transcriptomics deconvolution at single-cell resolution by Redeconve

Computational deconvolution with single-cell RNA sequencing data as reference is pivotal to interpreting spatial transcriptomics data, but the current methods are limited to cell type resolution. Here we present Redeconve, an algorithm to deconvolute spatial transcriptomics data at single-cell resolution, enabling interpretation of spatial transcriptomics data with thousands of nuanced cell states. We benchmarked Redeconve with the state-of-the-art algorithms on diverse spatial transcriptomics datasets and platforms and demonstrated the superiority of Redeconve in terms of accuracy, resolution, robustness, and speed. Applications to a human pancreatic cancer dataset revealed cancer clone-specific T cell infiltration, and application to lymph node samples identified subtle cellular surroundings between IgA+ and IgG+ spots, providing novel insights into tumor immunology and the regulatory mechanisms underlying antibody class switch.

bioinformatics↗

From whole genome to probiotic candidates: a study of potential Lactobacillus strain selection for vaginitis treatment

Vaginitis is a syndrome characterized by not only the invasion of pathogens, but also the lack of Lactobacillus. Lactobacillus supplementation emerged as an innovative therapy for vaginitis which targeted the vaginal microbiota in recent years. However, limited live biotherapeutic products were explicitly marketed for this. The aim of our study is to characterize the potential Lactobacillus candidates for enhancing the treatment of vaginitis. Initially, 98 Lactobacillus isolates with whole genome were selected into the candidate pool. The genomic pathways involved in the biosynthesis of probiotic metabolites, adhering ability and acid/bile resistance, as well as sequences of antibiotic resistance genes, plasmids, transposons, viruses, and prophages were annotated. A scoring model was then established based on genomic analysis for ranking the performance of the strains, and the top-performing ones were applied to in vitro tests for sub-screening. As a result, two candidates were selected, and their probiotic abilities were verified with three reference strains. L. crispatus LG55-27 and L. gasseri TM13-16 presented outstanding ability to produce D-lactate and adhere to human vaginal epithelial cells. They also showed higher antimicrobial activity against Gardnerella vaginalis, Escherichia coli, Candida albicans, Staphylococcus aureus and Pseudomonas aeruginosa than control ones. Their acid/bile-resistant ability suggested the potential of oral supplementation. Strain LG55-27 and TM13-16 also display improved effects on pH changes, and the production of inflammation cytokines in BV model rats. This study provided a probiotic dosage recommendation for vaginitis treatment by demonstrating an effective probiotic screening pipeline based on genome sequences, in vitro tests and in vivo BV model experiment.

microbiology↗

Organization, genomic targeting and assembly of three distinct SWI/SNF chromatin remodeling complexes in Arabidopsis

Switch defective/sucrose non-fermentable (SWI/SNF) complexes are evolutionarily conserved multi-subunit machines that play vital roles in chromatin architecture regulation for modulating gene expression via sliding or ejection of nucleosomes in eukaryotes. In plants, perturbations of SWI/SNF subunits often result in severe developmental disorders. However, the subunit composition, pathways of assembly, and genomic targeting of the plant SWI/SNF complexes remain undefined. Here, we reveal the organization, genomic targeting and assembly of three distinct Arabidopsis SWI/SNF complexes: BRAHMA-Associated SWI/SNF complexes (BAS), SPLAYED-Associated SWI/SNF complexes (SAS) and MINUSCULE-Associated SWI/SNF complexes (MAS). We show that BAS complexes are equivalent to human ncBAF, whereas SAS and MAS complexes evolve in multiple subunits unique to plants, suggesting a plant-specific functional evolution of SWI/SNF complexes. We further demonstrate overlapping and specific genomic targeting of the three plant SWI/SNF complexes on chromatin and reveal that SAS complexes are necessary for the correct genomic localization of the BAS complexes. Finally, we define the role of core module subunit in the assembly of the plant SWI/SNF complexes and highlight that ATPase module subunit is required for global complex stability and the interaction of core module subunits in SAS and BAS complexes in Arabidopsis. Together, our work highlights the divergence of SWI/SNF chromatin remodelers during the eukaryote evolution and provides a comprehensive landscape for understanding the plant SWI/SNF complexes organization, assembly, genomic targeting, and function. One-sentence summaryComprehensively define the organization, genomic targeting and assembly of three distinct SWI/SNF chromatin remodeling complexes in Arabidopsis

plant biology↗

Targeted degradation of PRC1 components, BMI1 and RING1B, via a novel protein complex degrader strategy

Polycomb repressive complex 1 (PRC1) is an essential epigenetic regulator that mainly controls histone H2A Lys119 mono-ubiquitination (H2AK119ub). BMI1 and RING1B are PRC1 core components and play critical roles in the development of various cancers. However, therapeutic agents targeting PRC1 are very limited, and small-molecule inhibitors of PRC1 displayed limited effectiveness in killing cancer cells. In this study, MS147, the first degrader of PRC1 core components, BMI1 and RING1B, was discovered via a novel protein complex degradation strategy that utilizes the target proteins interacting partner protein (EED) to degrade BMI1 and RING1B. MS147, which comprises an EED small-molecule binder linked to a ligand of the E3 ligase VHL, degrades BMI1 and RING1B in an EED-, VHL-, ubiquitination- and time-dependent manner. MS147 is selective and preferentially degrades BMI1 and RING1B over PRC2 core components: EED, EZH2 and SUZ12. Consequently, MS147 effectively reduces H2AK119ub, but not H3K27me3, which is catalyzed by PRC2. Furthermore, MS147, but not the parent EED binder or known PRC2 degraders, effectively inhibits the proliferation of cancer cell lines that are insensitive to EZH2 knockout or PRC2 degraders. Overall, this study provides a novel degrader targeting BMI1 and RING1B, which is a useful chemical tool to further investigate the roles of PRC1 in cancer, and a novel protein complex degradation strategy, which could potentially expand the degradable human proteome.

biochemistry↗

Protease inhibitor ASP enhances freezing tolerance by inhibiting protein degradation in Kumquat

Cold acclimation is a complex biological process leading to the development of freezing tolerance in plants. In this study, we demonstrated that cold-induced expression of protease inhibitor FmASP in a citrus relative species kumquat (Fortunella margarita (Lour.) Swingle) contributes to its freezing tolerance by regulating protein degradation. First, we found that only cold-acclimated kumquat plants, although with extensive leaf cellular damage during freezing, are able to resume their normal growth upon stress relief. To dissect the impact of cold acclimation on this extraordinary freezing tolerance, we performed protein abundance assay and quantitative proteomics analysis of kumquat leaves subjected to cold acclimation (4 {degrees}C), freezing treatment (-10 {degrees}C) and post-stress recovery (25 {degrees}C). FmASP and a few non-specific proteases were identified as differentially expressed proteins induced by cold acclimation and associated with stable protein abundance throughout the course of freezing treatment. FmASP was further characterized as a robust inhibitor that inhibits the degradation capacity of multiple proteases. In addition, heterogeneous expression of FmASP in Arabidopsis confirmed its positive function in freezing tolerance. Finally, we proposed a working model of FmASP and illustrated how this extracellular-localized protease inhibitor protects proteins from degradation and consequently maintains essential cellular function for freezing stress recovery. These findings revealed the important role of protease inhibition on freezing response and provide insights on how this role may help develop new strategies to enhance plant freezing tolerance. One-sentence summaryA protease inhibitor of Fortunella margarita enhances protein stability and freezing tolerance by regulating non-specific protease degradation

plant biology↗

Genetic Dissection of Mutual Interference between Two Consecutively Learned Tasks in Drosophila

Animals can continuously learn different tasks to adapt to changing environments and therefore have strategies to effectively cope with inter-task interference, including both proactive interference (Pro-I) and retroactive interference (Retro-I). Many biological mechanisms are known to contribute to learning, memory, and forgetting for a single task, however, mechanisms involved only when learning sequential different tasks are relatively poorly understood. Here, we dissect the respective molecular mechanisms of Pro-I and Retro-I between two consecutive associative learning tasks in Drosophila. Pro-I is more sensitive to inter-task interval (ITI) than Retro-I. They occur together at short ITI (<20 min), while only Retro-I remains significant at ITI beyond 20 min. Acutely overexpressing Corkscrew (CSW), an evolutionarily conserved protein tyrosine phosphatase SHP2, in mushroom body (MB) neurons reduces Pro-I, whereas acute knockdown of CSW exacerbates Pro-I. Such function of CSW is further found to rely on the {gamma} subset of MB neurons and the downstream Raf/MAPK pathway. In contrast, manipulating CSW does not affect Retro-I as well as a single learning task. Interestingly, manipulation of Rac1, a molecule that regulates Retro-I, does not affect Pro-I. Thus, our findings suggest that learning different tasks consecutively triggers distinct molecular mechanisms to tune proactive and retroactive interference.

animal behavior and cognition↗

Integrated analysis of intestinal microbiota and metabolomic reveals that decapod iridescent virus 1 (DIV1) infection induces secondary bacterial infection and metabolic reprogramming in Marsupenaeus japonicus

In recent years, with global warming and increasing marine pollution, some novel marine viruses have become widespread in the aquaculture industry, causing huge losses to the aquaculture industry. Decapod iridescent virus 1 (DIV1) is one of the newly discovered marine viruses that has been reported to be detected in a variety of farmed crustacean and wild populations. Previous studies have found that DIV1 can induce the Warburg effect. To further explore the effect of DIV1-induced metabolic reprogramming on Marsupenaeus japonicus intestinal metabolome and microbiota and the consequence on immune response, histological analysis, enzyme activity analysis and the integrated analysis of intestinal microbiome and metabolomics were performed in this study. The results showed that obvious injury in the intestinal mucosa was observed after DIV1 infection. The oxidative and antioxidant capacity of the shrimp intestine was unbalanced, the activity of lysozyme was decreased, and the activities of digestive enzymes were disordered, causing secondary bacterial infection. In addition, the increased abundance of harmful bacteria, such as Photobacterium and Vibrio, synergized with DIV1 to promote the Warburg effect and induce metabolic reprogramming, thereby providing material and energy for DIV1 replication. This study is the first to report the changes of intestinal microbiota and metabolites of M. japonicus under DIV1 infection, demonstrating that DIV1 can induce secondary bacterial infection and metabolic reprogramming, and several highly related bacteria and metabolites were screened as biomarkers. These biomarkers can be leveraged for diagnosis of pathogenic infections or incorporated as exogenous metabolites to enhance immune response.

microbiology↗