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Biology subjects

Zhou, X.

Publications and source records attributed to Zhou, X..

At least 397 records · Page 22Linked to original sources

Epidemiological evaluation and identification of the insect vector of soybean stay-green associated virus

In recent years, the emergence of soybean stay-green syndrome (SGS), also referred to as "zhengqing", in the Huang-Huai-Hai region of China has resulted in significant yield losses, with some areas experiencing a complete reduction in seed yield. SGS is a phenomenon characterized by the delayed senescence of soybean, resulting in stay-green leaves, flat pods, and stunted seed development at harvest. Our group was the first to identify a distinct geminivirus, named soybean stay-green associated geminivirus (SoSGV), as the causative agent of SGS by fulfilling Kochs postulate. To further understand the epidemiology of SoSGV, in this study, we collected 368 stay-green samples from 17 regions in 8 provinces including the Huang-Huai-Hai region and surrounding areas of China. The results showed that 228 samples tested positive for SoSGV (61.96%), and 96.93% of these positive samples showed severe pod deflation. Our epidemiological assessment reveals SGS caused by the SoSGV is prevalent in the fields, and it is undergoing geographical expansion and genetic differentiation. Additionally, we determined the other natural hosts grown in the Huang-Huai-Hai region of China. By capturing insects in the field and conducting laboratory vector transmission tests, we confirmed that the common brown leafhopper (Orosius orientalis) is the transmitting vector of SoSGV. With a better understanding of the epidemiology of SoSGV and its transmission, we can develop more effective strategies for managing and mitigating its impact on soybean yields.

microbiology↗

Modification of social cheating facilitates the stabilization and chronic infection of polymorphic Pseudomonas aeruginosa population

Chronic infection of the common bacterial pathogen Pseudomonas aeruginosa frequently leads to the coexistence of heterogeneous individuals to engage in several group behaviors. However, further evolution of the polymorphic P. aeruginosa population, including the dynamic change of social cooperation and its impact on host immune system, still remain elusive. We show that the evolution of P. aeruginosa in the patients with chronic obstructive pulmonary disease frequently selects the isolates deficient in producing the costly and sharable extracellular products for nutrient acquisition. The evolution of polymorphic P. aeruginosa population is mainly concentrated on modifying the adaptability of lasR mutants, which are typical cheaters in the competition of quorum-sensing-controlled extracellular proteases. Importantly, lasR mutants with varying degrees of evolution interact with wild-type P. aeruginosa in a framework termed cascaded public goods game to compete for extracellular proteases and siderophores, and thus perpetuate social cooperation under different conditions. Finally, we find that a polymorphic population comprised of lasR-intact P. aeruginosa and evolved lasR-mutant can minimize the host immune fluctuation for persistent colonization. This study demonstrates the multistage evolution and complex interaction of P. aeruginosa in adaptation to host lungs, and provides an explanation for the success of cooperation in public goods game.

microbiology↗

Spatially Resolved Proteomic Profiling Uncovers Structural and Functional Regulators of the Axon Initial Segment

The axon initial segment (AIS) is a specialized neuronal compartment required for action potential generation and neuronal polarity. However, understanding the mechanisms regulating AIS structure and function has been hindered by an incomplete knowledge of its molecular composition. Here, using immuno-proximity biotinylation we further define the AIS proteome and its dynamic changes during neuronal maturation. Among the many AIS proteins identified, we show that SCRIB is highly enriched in the AIS both in vitro and in vivo, and exhibits a periodic architecture like the axonal spectrin-based cytoskeleton. We found that ankyrinG interacts with and recruits SCRIB to the AIS. However, loss of SCRIB has no effect on ankyrinG. This powerful and flexible approach further defines the AIS proteome and provides a rich resource to elucidate the mechanisms regulating AIS structure and function.

neuroscience↗

Endothelial cell-derived lactate triggers mesenchymal stem cell histone lactylation to attenuate osteoporosis

Blood vessels play a role in osteogenesis and osteoporosis; however, the role of vascular metabolism is unclear. The present study found that ovariectomized mice exhibit reductions in bone blood vessel density and expression of endothelial glycolytic regulator pyruvate kinase M2 (PKM2). Additional data showed that endothelial cell (EC)-specific deletion of Pkm2 impair osteogenesis and worsen osteoporosis in mice. This was attributed to the impaired differentiation ability toward osteoblast of bone mesenchymal stem cells (BMSCs). Mechanistically, EC-specific deletion of Pkm2 reduce serum lactate levels secreted by ECs, which affect histone lactylation of BMSCs. We identified collagen type I alpha 2 chain, cartilage oligomeric matrix protein, ectonucleotide pyrophosphatase/phosphodiesterase 1, and transcription factor 7 like 2 as histone H3K18 lactylation-regulated osteogenic genes using joint CUT&Tag and RNA-sequencing analyses. The overexpression of PKM2 in ECs, addition of lactate, and exercise were observed to restore the phenotype of endothelial Pkm2-deficient mice. Furthermore, metabolomics of the serum indicated that osteoporosis patients showed a relatively low lactate level. The histone lactylation and related osteogenic genes of BMSCs in osteoporosis patients also decreased. In conclusion, the glycolysis of ECs fuels the differentiation of BMSCs into osteoblasts through histone lactylation, and exercise partially ameliorates osteoporosis through increased serum lactate.

cell biology↗

Efficient and scalable prediction of spatio-temporal stochastic gene expression in cells and tissues using graph neural networks

The simulation of spatial stochastic models is highly computationally expensive, an issue that has severely limited our understanding of the spatial nature of gene expression. Here we devise a graph neural network based method to learn, from stochastic trajectories in a small region of space, an effective master equation for the time-dependent marginal probability distributions of mRNA and protein numbers at sub-cellular resolution for every cell in a tissue. Numerical solution of this equation leads to accurate results in a small fraction of the computation time of standard simulation methods. Moreover its predictions can be extrapolated to a spatial organisation (a cell network topology) and regions of parameter space unseen in its neural network training. The scalability and accuracy of the method suggest it is a promising approach for whole cell modelling and for detailed comparisons of stochastic models with spatial genomics data.

systems biology↗

UBE3A and transsynaptic complex NRXN1-CBLN1-GluD1 in a hypothalamic VMHvl-arcuate feedback circuit regulates aggression

The circuit origins of aggression in autism spectrum disorder remain undefined. Here we report Tac1-expressing glutamatergic neurons in ventrolateral division of ventromedial hypothalamus (VMHvl) drive intermale aggression. Aggression is increased due to increases of Ube3a gene dosage in the VMHvl neurons when modeling autism due to maternal 15q11-13 triplication. Targeted deletion of increased Ube3a copies in VMHvl reverses the elevated aggression adult mice. VMHvl neurons form excitatory synapses onto hypothalamic arcuate nucleus AgRP/NPY neurons through a NRXN1-CBLN1-GluD1 transsynaptic complex and UBE3A impairs this synapse by decreasing Cbln1 gene expression. Exciting AgRP/NPY arcuate neurons leads to feedback inhibition of VMHvl neurons and inhibits aggression. Asymptomatic increases of UBE3A synergize with a heterozygous deficiency of presynaptic Nrxn1 or postsynaptic Grid1 (both ASD genes) to increase aggression. Targeted deletions of Grid1 in arcuate AgRP neurons impairs the VMHvl to AgRP/NPY neuron excitatory synapses while increasing aggression. Chemogenetic/optogenetic activation of arcuate AgRP/NPY neurons inhibits VMHvl neurons and represses aggression. These data reveal that multiple autism genes converge to regulate the VMHvl-arcuate AgRP/NPY glutamatergic synapse. The hypothalamic circuitry implicated by these data suggest impaired excitation of AgRP/NPY feedback inhibitory neurons may explain the increased aggression behavior found in genetic forms of autism. One Sentence SummaryA feedback circuit in the hypothalamus that inhibits aggression is impaired by converging autism genetic defects.

neuroscience↗

Arsenic is a potent co-mutagen of ultraviolet light

Environmental co-exposures are widespread and are major contributors to carcinogenic mechanisms. Two well-established environmental agents causing skin cancer are ultraviolet radiation (UVR) and arsenic. Arsenic is a known co-carcinogen that enhances UVRs carcinogenicity. However, the mechanisms of arsenic co-carcinogenesis are not well understood. In this study, we utilized primary human keratinocytes and a hairless mouse model to investigate the carcinogenic and mutagenic properties of co-exposure to arsenic and UVR. In vitro and in vivo exposures revealed that, on its own, arsenic is neither mutagenic nor carcinogenic. However, in combination with UVR, arsenic exposure has a synergistic effect leading to an accelerated mouse skin carcinogenesis as well as to more than 2-fold enrichment of UVR mutational burden. Notably, mutational signature ID13, previously found only in UVR-associated human skin cancers, was observed exclusively in mouse skin tumors and cell lines jointly exposed to arsenic and UVR. This signature was not observed in any model system exposed purely to arsenic or purely to UVR, making ID13 the first co-exposure signature to be reported using controlled experimental conditions. Analysis of existing genomics data from basal cell carcinomas and melanomas revealed that only a subset of human skin cancers harbor ID13 and, consistent with our experimental observations, these cancers exhibited an elevated UVR mutagenesis. Our results provide the first report of a unique mutational signature caused by a co-exposure to two environmental carcinogens and the first comprehensive evidence that arsenic is a potent co-mutagen and co-carcinogen of UVR. Importantly, our findings suggest that a large proportion of human skin cancers are not formed purely due to UVR exposure but rather due to a co-exposure of UVR and other co-mutagens such as arsenic.

cancer biology↗

Targeting GDF15 as a potential therapy for low back pain originating from endplate

The overactivation of osteoclasts in the endplate is one of the most important causes of low back pain (LBP) originating from endplate. Transforming growth factor-{beta} family has been demonstrated to play an important role during osteoclast differentiation. GDF15 was reported to participate in several pathological states. In this study, we reported that the lumbar spine instability (LSI) induced the overactivation of osteoclasts and CD31hiEmcnhi endothelial vessels in the bony endplate. In addition, the expression of GDF15 in human disc samples and mice models were also increased. GDF15 could promote the fusion of preosteoclasts via Rac1/Cdc42/PAK/Cofilin axis, and facilitate the angiogenesis via the secretion of PDGF-BB. Furthermore, we proved that the GDF15 inhibitor, CTL-002 could reduce the expression of GDF15 in the endplate and alleviate the overactivation of osteoclasts and CD31hiEmcnhi endothelial vessels induced by LSI in vivo. In conclusion, we demonstrated that GDF15 could regulates the fusion of preosteoclasts and targeting GDF15 in the endplate served as a novel anabolic therapy for low back pain treatment.

cell biology↗

Rigosertib promotes anti-tumor immunity via autophagic degradation of PD-L1 in colorectal cancer cells

Rigosertib (RGS) is a benzyl styryl sulfone which exhibits impressive cytotoxicity in cancer cells. However, its modulating effect on tumor immune microenvironment remains elusive. In our experiments, compared with immunodeficient mouse model, increased tumor growth arrest and robust anti-tumor immunity were observed in RGS-treated colorectal cancer (CRC) xenograft tumors in immunocompetent mice. Intriguingly, RGS markedly down-regulated programmed cell death ligand 1 (PD-L1) expression in both vivo and in vitro. Meanwhile, RGS increased autophagic vacuole number in CRC cells as seen by transmission electron microscopy and immunofluorescence. Moreover, increased LC3-II level and tandem- mRFP- GFP- LC3 labeled vacuole accumulation demonstrated RGS-induced autophagic flux. Mechanistically, it is the activation of AMP-activated protein kinase-UNC-51-like kinase 1 (AMPK-ULK1) axis, rather than the canonical mTOR signaling pathway, that plays a pivotal role in RGS-induced autophagy. AMPK-ULK1 dependent autophagy inhibition, by either short interfering RNA or chemical inhibitors, blocked RGS-induced PD-L1 degradation. Finally, RGS exhibited synergistic anti-tumor activity with cytotoxic T-lymphocyte-associated protein 4 monoclonal antibody in the CRC xenograft model. Furthermore, apart from the immunomodulatory effect, we also confirmed the direct cytotoxicity of RGS in inducing mitochondria-related apoptosis. Altogether, considering its PD-L1 inhibitory and cytotoxic effects, RGS could be a promising drug for CRC therapy.

cancer biology↗

Protein Sequence Design by Entropy-based Iterative Refinement

Inverse Protein Folding (IPF) is an important task of protein design, which aims to design sequences compatible with a given backbone structure. Despite the prosperous development of algorithms for this task, existing methods tend to leverage limited and noisy residue environment when generating sequences. In this paper, we develop an iterative sequence refinement pipeline, which can refine the sequence generated by existing sequence design models. It selects and retains reliable predictions based on the models confidence in predicted distributions, and decodes the residue type based on a partially visible environment. The proposed scheme can consistently improve the performance of a number of IPF models on several sequence design benchmarks, and increase sequence recovery of the SOTA model by up to 10%. We finally show that the proposed model can be applied to redesign Transposon-associated transposase B. 8 variants exhibit improved gene editing activity among the 20 variants we proposed. Our code and a demo of the refinement pipeline are provided in the online colab.

bioinformatics↗

An orally bioavailable 4-phenoxy-quinoline compound as a potent AURKB relocation blocker for cancer treatment

We investigated a novel 4-phenoxy-quinoline-based scaffold that mislocalizes the essential mitotic kinase, AURKB. Here, we evaluated the impact of halogen substitutions (F, Cl, Br, I) on this scaffold with respect to various drug parameters. Br-substituted LXY18 was found to be a potent and orally bioavailable disruptor of cell division, at sub-nanomolar concentrations. LXY18 prevents cytokinesis by blocking AURKB relocalization in mitosis and exhibits broad-spectrum antimitotic activity in vitro. With a favorable PK profile, it shows widespread tissue distribution including the blood-brain barrier penetrance and effective accumulation in tumor tissues. More importantly, it markedly suppresses tumor growth. The novel mode of action of LXY18 may eliminate some drawbacks of direct catalytic inhibition of AURKs. Successful development of LXY18 as a clinical candidate for cancer treatment could enable a new, less toxic means of antimitotic attack that avoids drug resistance mechanisms.

cancer biology↗

Senescence of cortical neurons following persistent DNA double-strand breaks induces cerebrovascular lesions

DNA double strand breaks (DSBs), neuroinflammation, and vascular alterations in the brain are all associated with neurodegenerative disorders. However, the interconnections between these neuropathological changes and how they act synergistically to promote irreversible neurodegeneration remain unclear. Here we show that abrogating the BRCA1-associated protein Brap in cerebral cortical neurons, as opposed to vascular endothelium cells, causes cerebrovascular defects. This non-cell autonomous effect is mediated by cellular senescence resulting from persistent neuronal DSBs. We show that in the state of senescence, there is a massive upregulation of genes involved in cell secretion, inflammatory responses, and vascular changes, which coincides with cerebral microclots and microbleeds. The vascular lesions intertwine with neuroinflammation and exacerbate neuronal DSBs, culminating in oxidative stress, metabolic alteration, and downregulation of genes essential for neuronal function. By demonstrating the cerebrovascular impact of cortical neuronal DSBs, our data suggest that senescence-associated secretory phenotype can initiate brain-wide neurodegeneration.

neuroscience↗

Visualization and review of reads alignment on the graphical pan-genome with VAG

Recent advances in pangenomics have led to the rapid development of graph-based pangenomes that code genetic variant as nodes and edges preserve the contiguity of the sequence and structural variation between individuals. Data visualization is an essential component of genomic data analysis. However, the further application of the graph-based pangenome is still suffered from lacking bioinformatics tools to visualize graph format pangenomes and understand the reads alignment on graph pangenomes. In this research, we developed a novel bioinformatics platform, VAG (Visualizing read alignments in graph genomes), to overcome these challenges. VAG includes multifunctional modules integrated into a single command line and an online visualization platform supported through a web server. This tool can extract specific sequence regions from a graph pangenome and display read alignments on different paths of a graph pangenome. In addition, VAG provides population-level presence/absence variations frequency analysis and sequence path navigation to identify the population differentiation regions. To demonstrate the usage, we investigated genetic variations using a rice graph pangenome with population-level sequencing data to identify important genes and gene clusters underlying the indica-japonica differentiation with VAG. After investigating read alignments on the graph pangenome, we identified many false-positive alignments due to TE insertions. To reduce the impact of these misleading alignments, we developed a navigation module to determine and filter those false-positive alignments based on the pair-end alignment information. The utilization of mate-pair information in VAG provides a reliable reference for variation identification. Additionally, we developed a VAG web server to provide a user-friendly and interactive platform to visualize the read alignment data. VAG was also applied to SV discovery in the cucumber and soybean graph-based pangenome and details of VAG can be accessed by the following website (https://ricegenomichjx.xiaomy.net/VAG/sequenceextraction.php).

bioinformatics↗

Multiple conformational states assembly of multidomain proteins using evolutionary algorithm based on structural analogues and sequential homologues

With the breakthrough of AlphaFold2, nearly all single-domain protein structures can be built at experimental resolution. However, accurate modelling of full-chain structures of multidomain proteins, particularly all relevant conformations for those with multiple states remain challenging. In this study, we develop a multidomain protein assembly method, M-SADA, for assembling multiple conformational states. In M-SADA, a multiple population-based evolutionary algorithm is proposed to sample multiple conformational states under the guidance of multiple energy functions constructed by combining homologous and analogous templates with inter-domain distances predicted by deep learning. On a developed benchmark dataset containing 72 multidomain proteins with multiple conformational states, the performance of M-SADA is significantly better than that of AlphaFold2 on multiple conformational states modelling, where 29/72 (40.3%) of proteins can be assembled with a TM-score >0.90 for highly distinct conformational states with M-SADA while AlphaFold2 does so in only 2/72 (2.8%) of proteins. Furthermore, M-SADA is tested on a developed benchmark dataset containing 296 multidomain proteins with single conformational state, and results show that the average TM-score of M-SADA on the best models is 0.913, which is 5.2% higher than that of AlphaFold2 models (0.868).

bioinformatics↗

Exploration of the Link Between COVID-19 and Alcoholic Hepatitis from the Perspective of Bioinformatics and Systems Biology

ObjectiveSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been suggested to purpose threats to health of mankind. Alcoholic hepatitis (AH) is a life-threatening acute and chronic liver failure that takes place in sufferers who drink excessively. During the epidemic, AH has an increasing incidence of severe illness and mortality. However, for these two diseases, the intrinsic relationship of molecular pathogenesis, as well as common therapeutic strategies are still poorly understood. MethodsThe transcriptome of the COVID-19 and AH has been compared to obtain the altered genes and hub genes were screened out through protein-protein interaction (PPI) network analysis. Via gene ontology (GO), pathway enrichment and transcription regulator analysis, a deeper appreciation of the interplay mechanism between hub genes were established. ResultsWith 181 common differentially expressed genes (DEGs) of AH and COVID-19 were obtained, 10 hub genes were captured. Follow-up studies located that these 10 genes typically mediated the diseases occurrence by regulating the activities of the immune system. Other results suggest that the common pathways of the two ailments are enriched in regulating the function of immune cells and the release of immune molecules. ConclusionThis study reveals the common pathogenesis of COVID-19 and AH and assist to discover necessary therapeutic targets to combat the ongoing pandemic induced via SARS-CoV-2 infection and acquire promising remedy strategies for the two diseases.

bioinformatics↗

Evolutionary transcriptomics reveals longevity mostly driven by polygenic and indirect selection in mammals

The maximum lifespan varies more than 100-fold in mammals. This experiment of nature may uncover of the evolutionary forces and molecular features that define longevity. To understand the relationship between gene expression variation and maximum lifespan, we carried out a comparative transcriptomics analysis of liver, kidney, and brain tissues of 106 mammalian species. We found that expression is largely conserved and very limited genes exhibit common expression patterns with longevity in all the three organs analyzed. However, many pathways, e.g., "Insulin signaling pathway", and "FoxO signaling pathway", show accumulated correlations with maximum lifespan across mammals. Analyses of selection features further reveal that methionine restriction related genes whose expressions associated with longevity, are under strong selection in long-lived mammals, suggesting that a common approach could be utilized by natural selection and artificial intervention to control lifespan. These results suggest that natural lifespan regulation via gene expression is likely to be driven through polygenic model and indirect selection.

evolutionary biology↗

Humanized CD36 mouse model supports the preclinical evaluation of therapeutic candidates targeting CD36

CD36 (also known as scavenger receptor B2) is a multifunctional receptor that mediates lipid uptake, advanced oxidation protein products, and immunological recognition, and has roles in lipid accumulation, apoptosis, as well as in metastatic colonization in cancer. CD36 is involved in tumor immunity, metastatic invasion, and therapy resistance through various molecular mechanisms. Targeting CD36 has emerged as an effective strategy for tumor immunotherapy. In this study, we have successfully generated a novel CD36 humanized mouse strain where the sequences encoding the extracellular domains of the mouse Cd36 gene were replaced with the corresponding human sequences. The results showed that CD36 humanized mice expressed only human CD36, and the proportion of each lymphocyte was not significantly changed compared with wild-type mice. Furthermore, CD36 monoclonal antibody could significantly inhibit tumor growth after treatment. Therefore, the CD36 humanized mice provided a validated preclinical mouse model for the evaluation of tumor immunotherapy targeting CD36.

immunology↗

Phylogenomics reveals pervasive ancient introgression in the radiation of macaques

The genus Macaca, with 23 species assigned into four to seven species groups, exhibits the largest geographic range and represents the most successful adaptive radiation of nonhuman primates. Here, we conducted phylogenomic analyses of 16 newly generated and eight published macaque genomes and found a strong support for the division of this genus into seven species groups. Both ancient hybrid and incomplete lineage sorting (ILS) have contributed to the radiation and evolution of macaques. Particularly, the contradicting phylogenetic positions among silenus/nigra, fascicularis/mulatta and arctoides/sinica lineages were likely resulted from high level of ILS and potential hybridization between the ancestors of the arctoides/sinica and silenus/nigra lineages. Furthermore, an integrated scenario for macaque radiation is reconstructed by the help of the dated phylogenetic tree combined with documented history records. This study provides insights into ancient introgression involved in the radiation of macaques, which may help us to understand the rapid speciation of nonhuman primates.

evolutionary biology↗