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Biology subjects

Zhou, X.

Publications and source records attributed to Zhou, X..

At least 415 records · Page 23Linked to original sources

Bioinformatics Approaches to Determine the Effect of SARS-CoV-2 Infection on Patients with Intrahepatic Cholangiocarcinoma

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causal agent of coronavirus disease 2019 (COVID-19), has infected millions of individuals throughout the world, which poses a serious threat to human health. COVID-19 is a systemic disease that affects tissues and organs, including the lung and liver. Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) are the most common liver cancer, and cancer patients are particularly at high risk of SARS-CoV-2 infection. The relationship between HCC and COVID-19 has been reported in previous studies, but ICC has been rare. With the methods of systems biology and bioinformatics, this study explored the link between COVID-19 and ICC. Transcriptional profiling of COVID-19 and ICC were obtained from the GEO database. A total of 70 common differentially expressed gene (DEGs) of both diseases were identified to investigate shared pathways. Then top-ranked 10 key DEGs (SCD, ACSL5, ACAT2, HSD17B4, ALDOA, ACSS1, ACADSB, CYP51A1, PSAT1, and HKDC1) were identified as hub genes by protein-protein interaction (PPI) network analysis. In addition, transcriptional regulatory networks regulating hub genes were revealed by hub Gene-transcription factor (TF) interaction analysis and hub gene-microRNA (miRNAs) interaction analysis. This study is expected to provide new references for future research and treatment of COVID-19 and ICC.

bioinformatics↗

Crystal structure of a mammalian CMTM6 and its interaction model with PD-L1

CKLF-like MARVEL transmembrane domain-containing protein 6 (CMTM6) is a master regulator of PD-L1. By binding PD-L1 at the plasma membrane and recycling endosomes, CMTM6 prevents the lysosomal degradation of PD-L1 and maintains its cell surface expression, thus stabilizing the inhibitory PD-1/PD-L1 axis. However, the mechanism of CMTM6/PD-L1 interaction is unknown. Here we report the first experimentally determined structure of CMTM6 from bovine. Combined with a low-resolution cryo-EM map, computational docking analysis and a protein binding assay an interaction model between CMTM6 and PD-L1 was proposed, providing a structural framework for the CMTM6 regulation on PD-L1.

biophysics↗

Integrating spatial transcriptomics data across different conditions, technologies, and developmental stages

With the rapid generation of spatial transcriptomics (ST) data, integrative analysis of multiple ST datasets from different conditions, technologies, and developmental stages is becoming increasingly important. However, identifying shared and specific spatial domains across ST datasets of multiple slices remains challenging. To this end, we develop a graph attention neural network STAligner for integrating and aligning ST datasets, enabling spatially-aware data integration, simultaneous spatial domain identification, and downstream comparative analysis. We apply STAligner to the integrative analysis of ST datasets of the human cortex slices from different samples, the mouse olfactory bulb slices generated by two profiling technologies, the mouse hippocampus tissue slices under normal and Alzheimers disease conditions, and the spatiotemporal atlases of mouse organogenesis. STAligner efficiently captures the shared tissue structures across different slices, the disease-related substructures, and the dynamical changes during mouse embryonic development. Additionally, the shared spatial domain and nearest neighbor pairs identified by STAligner can be further considered as corresponding pairs to guide the three-dimensional reconstruction of consecutive slices, achieving more accurate local structure-guided registration results than the existing method.

bioinformatics↗

Retrieving the near-complete genome of a threatened bird from wild frozen samples

Conservation genomics often relies on non-invasive methods to obtain DNA fragments which limit the power of multi-omic analyses for threatened species. Collecting samples from frozen dead animals in the wild provides an alternative approach to obtaining high-quality nucleic acids. Here, we report multi-omic analyses based on a well-preserved great bustard individual (Otis tarda, Otidiformes) of a recent death found in the mountainous region in Gansu, China. We generated a near-complete genome assembly (OTswu) having only 18 gaps scattering in 8 out of the 40 assembled chromosomes. Unlikely most other bird genome assemblies, OTswu contains complete chromosome models (2n = 80). We demonstrated that the great bustard genome likely retained the ancestral avian karyotype. We also characterized the DNA methylation landscapes of OTswu which are strongly correlated with GC content and gene expression. Our phylogenomic analysis suggested Otidiformes and Musophagiformes were sister groups that diverged from each other 46.3 million years ago. The genetic diversity of great bustard was found the lowest among the four available Otidiformes genomes, possibly due to population declines during past glacial periods. As one of the heaviest migratory birds, great bustard possesses several expanded gene families related to cardiac contraction, actin contraction, calcium ion signaling transduction, as well as positively selected genes enriching for metabolism. Finally, we identified an extremely young evolutionary stratum on the sex chromosome, a rare case among Neoaves. Together, our study combining long-read sequencing and RNA-seq technology provides a working strategy for conducting multi-omic analyses for threatened species by retrieving high-quality nucleic acids from dead animals frozen in the wild.

genomics↗

Integrated proteomics reveals the landscape of autophagy degradation in human neurons and autophagy receptors regulating neuronal activity

Autophagy is a catabolic and self-degradative process crucial for maintaining cellular homeostasis. Malfunctional autophagy is implicated in neurodevelopmental and neurodegenerative diseases. However, the exact role and targets of autophagy in human neurons remain elusive. Here we reported a systematic investigation of neuronal autophagy targets through integrated proteomics. Deep proteomic profiling of multiple autophagy-deficient lines of human induced neurons, mouse brains, and LC3-interactome uncovers a role of neuronal autophagy in targeting primarily endoplasmic reticulum (ER), mitochondria, endosome, Golgi apparatus, synaptic vesicle (SV) proteins, and cAMP-PKA pathway, for degradation. Tubular ER and specific SV proteins are significant autophagy cargos in the axons. Functional validation identified calumenin as an ER resident autophagy receptor and illuminated a role of autophagy in regulating PKA and neuronal activity through AKAP11-mediated degradation. Our study thus reveals the landscape of autophagy degradation in human neurons and offers molecular insight into mechanisms of neurological disorders linked to autophagy deficiency. HighlightO_LIIntegrated proteomics reveals the landscape of autophagy degradation in human neurons C_LIO_LIAutophagy clears tubular ER and selective ER and synaptic vesicle proteins in neurons C_LIO_LICalumenin is an ER resident autophagy receptor C_LIO_LIAutophagy controls PKA pathway and neuronal activity through autophagy receptor AKAP11 C_LI

neuroscience↗

Myofibroblast Ccn3 is regulated by Yap and Wwtr1 and contributes to adverse cardiac outcomes

While Yap and Wwtr1 regulate resident cardiac fibroblast to myofibroblast differentiation following cardiac injury, their role specifically in activated myofibroblasts remains unexplored. Here we assess the pathophysiological and cellular consequence of genetic depletion of Yap alone (Yapfl/fl;PostnMCM) or Yap and Wwtr1 (Yapfl/fl;Wwtr1fl/+;PostnMCM) in adult mouse myofibroblasts following myocardial infarction and identify and validate novel downstream factors specifically in cardiac myofibroblasts that mediate pathological remodeling. Following myocardial infarction, depletion of Yap in myofibroblasts had minimal effect on heart function while depletion of Yap/Wwtr1 resulted in smaller scars, reduced interstitial fibrosis, and improved ejection fraction and fractional shortening. Single cell RNA sequencing of interstitial cardiac cells 7 days post infarction showed suppression of pro-fibrotic genes in fibroblasts derived from Yapfl/fl,Wwtr1fl/+;PostnMCM hearts. In vivo myofibroblast depletion of Yap/Wwtr1 as well in vitro knockdown of Yap/Wwtr1 dramatically decreased RNA and protein expression of the matricellular factor Ccn3. Administration of recombinant CCN3 to adult mice following myocardial infarction remarkably aggravated cardiac function and scarring. CCN3 administration drove myocardial gene expression of pro-fibrotic genes in infarcted left ventricles implicating CCN3 as a novel driver of cardiac fibrotic processes following myocardial infarction.

physiology↗

FMRP phosphorylation modulates neuronal translation through YTHDF1

Translation activation of local synaptic mRNAs is critical to learning and memory1-3. Despite extensive studies on how phosphorylation of ribosomal proteins and translation factors enables timely response to exogenous stimuli4, our knowledge on molecular pathways utilized by RNA binding proteins (RBPs) to control translation of specific mRNAs remains incomplete. We have previously found that YTHDF1 regulates depolarization-induced protein synthesis by promoting translation of N6-methyladenosine (m6A)-modified transcripts5. Here we report an unexpected mechanism that the stimuli-induced neuronal translation is mediated by phosphorylation of a YTHDF1-binding protein FMRP. Phosphorylation of FMRP serine 499 induced by neuronal depolarization alters the condensing behavior of prion-like protein YTHDF1. Unphosphorylated FMRP sequesters YTHDF1 away from the translation initiation complex, whereas the stimulation-induced FMRP phosphorylation releases YTHDF1 to form translational active condensates with the ribosome to activate translation of YTHDF1 target transcripts. In fragile X syndrome (FXS) models characterized by low FMRP expression, we observed YTHDF1-mediated hyperactive translation, which notably impacts FXS pathophysiology. Developmental defects in an FXS forebrain organoid model could be reversed by a selective small-molecule inhibitor of YTHDF1 which acts by suppressing its condensation in neurons. We characterized transcriptome-wide mRNA translation with inhibitor treatment in organoids and identified targets that explain alleviated FXS pathology. Our study thus reveals FMRP and its phosphorylation as an important regulator of the activity-dependent translation during neuronal development and stimulation, and identifies YTHDF1 as a potential therapeutic target for FXS in which developmental defects caused by FMRP depletion could be reversed through YTHDF1 inhibition.

molecular biology↗

ABLs and TMKs are co-receptors for extracellular auxin

Extracellular perception of auxin, an essential phytohormone in plants, has been debated for decades. Auxin binding protein 1 (ABP1) physically interacts with quintessential transmembrane kinases (TMKs) and was proposed to act as an extracellular auxin receptor, but its role was disputed because abp1 knockout mutants lack obvious morphological phenotypes. Here we identified two new auxin-binding proteins, ABL1 and ABL2, that are localized to the apoplast and directly interact with the extracellular domain of TMKs in an auxin-dependent manner. Furthermore, functionally redundant ABL1 and ABL2 genetically interact with TMKs and exhibit functions that are overlapping with those of ABP1 as well as independent of ABP1. Importantly, the extracellular domain of TMK1 itself binds auxin and synergizes with either ABP1 or ABL1 in auxin binding. Thus, our findings discovered new auxin receptors ABL1 and ABL2 having functions overlapping with but distinct from ABP1 and acting together with TMKs as co-receptors for extracellular auxin.

plant biology↗

Three-dimensional molecular architecture of mouse organogenesis

Mammalian embryos have sophisticated cell organizations that are orchestrated by molecular regulation at cellular and tissue level. It has recently been appreciated that the cells that make up the animal body themselves harbor significant heterogeneity in the context of both cellular and particularly spatial dimension. However, current spatial transcriptomics profiling of embryonic tissues either lack three-dimensional representation or are restricted to limited depth and organs. Here, we reported a holistic spatial transcriptome atlas of all major organs at embryonic day 13.5 of mouse embryo and delineated a 3D rendering of the molecular regulation of embryonic patterning. By integrating with corresponding single-cell transcriptome data, the spatial organogenesis atlas provides rich molecular annotation of the dynamic organ nature, spatial cellular interaction, embryonic axes and divergence of cell fates underlying mammalian development, which would pave the way for precise organ-engineering and stem-cell based regenerative medicine.

developmental biology↗

CRISPR/FnCas12a-mediated efficient multiplex and iterative genome editing in bacterial plant pathogens without donor DNA templates

CRISPR-based genome editing technology is revolutionizing prokaryotic research, but it has been rarely studied in bacterial plant pathogens. Here, we have developed a targeted genome editing method with no requirement of donor templates for convenient and efficient gene knockout in Xanthomonas oryzae pv. oryzae (Xoo), one of the most important bacterial pathogens on rice, by employing the heterogenous CRISPR/Cas12a from Francisella novicida and NHEJ proteins from Mycobacterium tuberculosis. FnCas12a nuclease generated both small and large DNA deletions at the target sites as well as it enabled multiplex genome editing, gene cluster deletion and plasmid cure in the Xoo PXO99A strain. Accordingly, a non-TAL effector-free polymutant strain PXO99AD25E, which lacks all 25 Xop genes involved in Xoo pathogenesis, has been engineered through iterative genome editing. Whole-genome sequencing analysis indicated that FnCas12a did not have a noticeable off-target effect. In addition, we revealed that these strategies are also suitable for targeted genome editing in another bacterial plant pathogen Pseudomonas syringae pv. tomato (Pst). We believe that our bacterial genome editing method will greatly expand the CRISPR study on microorganisms and advance our understanding of the physiology and pathogenesis of Xoo.

microbiology↗

Fear of missing out (FOMO) associates with reduced cortical thickness in core regions of the posterior default mode network and higher levels of problematic smartphone and social media use

Fear of missing out (FOMO) promotes the desire or urge to stay continuously connected with a social reference group and updated on their activities, which may result in escalating and potentially addictive smartphone and social media use. The present study aimed to determine whether the neurobiological basis of FOMO encompasses core regions of the reward or social brain, and the associations with the level of problematic smartphone or social media use. We capitalized on a dimensional neuroimaging approach to examine cortical thickness and subcortical volume associations in a comparably large sample of healthy young individuals (n = 167). Meta-analytic network and behavioral decoding were employed to further characterize the identified regions. Higher levels of FOMO associated with lower cortical thickness in the precuneus. In contrast, no associations between FOMO and variations in striatal morphology were observed. Meta-analysis decoding revealed that the identified precuneus region exhibited a strong functional interaction with the default mode network (DMN) engaged in social cognitive and self-referential domains. Together the present findings suggest that individual variations in FOMO are associated with the brain structural architecture of the right precuneus, a core hub within a large-scale functional network resembling the DMN involved in social and self-referential processes. FOMO may promote escalating social media and smartphone use via social and self-referential processes rather than reward-related processes per se.

neuroscience↗

Research on protein structure prediction and folding based on novel remote homologs recognition

Recognition of remote homologous structures is a necessary module in AlphaFold2 and is also essential for the exploration of protein folding pathways. Here, we developed a new method, PAthreader, which identifies remote homologous structures based on the three-track alignment of distance profiles and structure profiles originated from PDB and AlphaFold DB by deep learning. Based on the identified templates, we further enhanced state-of-the-art modelling method and explored protein folding pathways based on the residue frequency distribution of homologs and the secondary structure. The results show that the average accuracy of templates identified by PAthreader is 11.6% higher than those of HHsearch on 551 nonredundant proteins. In terms of structure modelling, PAthreader improves the performance of AlphaFold2 and ranks first in CAMEO blind test for the last three months. Furthermore, we explored protein folding pathways for 37 proteins. The results are almost consistent with biological experiments for 7 proteins, and the remaining 30 human proteins have yet to be verified by biological experiments, revealing that folding information can be exploited from remote homologous structures.

bioinformatics↗

Developing a standardized but extendable framework to increase the findability of infectious disease datasets

Biomedical datasets are increasing in size, stored in many repositories, and face challenges in FAIRness (findability, accessibility, interoperability, reusability). As a Consortium of infectious disease researchers from 15 Centers, we aim to adopt open science practices to promote transparency, encourage reproducibility, and accelerate research advances through data reuse. To improve FAIRness of our datasets and computational tools, we evaluated metadata standards across established biomedical data repositories. The vast majority do not adhere to a single standard, such as Schema.org, which is widely-adopted by generalist repositories. Consequently, datasets in these repositories are not findable in aggregation projects like Google Dataset Search. We alleviated this gap by creating a reusable metadata schema based on Schema.org and catalogued nearly 400 datasets and computational tools we collected. The approach is easily reusable to create schemas interoperable with community standards, but customized to a particular context. Our approach enabled data discovery, increased the reusability of datasets from a large research consortium, and accelerated research. Lastly, we discuss ongoing challenges with FAIRness beyond discoverability.

bioinformatics↗

A novel pH-sensitive reporter reveals the cocaine-regulated trafficking of dopamine transporters in neuronal processes

The dopamine transporter (DAT) mediated DA reuptake is a major molecular mechanism for termination of dopaminergic signaling in the brain. Psychoactive substances such as cocaine act by inhibition of plasma membrane DAT function as well as by altering its expression. The precise manner and mechanism by which cocaine regulates DAT trafficking, especially at neuronal processes, are poorly understood. We have now engineered a novel pH-sensitive reporter for DAT by conjugating pHluorin to the second exofacial loop of human DAT. We show that DAT-pHluorin can be used to study DAT localization and its dynamic trafficking at neuronal processes. Using DAT-pHluorin we show that unlike neuronal soma and dendrites, which contain majority of the DATs in weakly acidic intracellular compartments, axonal DATs at both shafts and boutons are primarily (75%) localized to the plasma membrane, while varicosities contain abundant intracellular DAT within acidic intracellular structures. Using this novel reporter, we show, for the first time, that cocaine exposure leads to a brief DAT internalization followed by membrane reinsertion that lasts for days. We further show that the cocaine-induced DAT trafficking is sensitive to the activities of Synaptojanin1 phosphatase. Thus, our study using the newly engineered DAT optical reporter reveals the previously unknown dynamics and molecular regulation for cocaine-regulated DAT trafficking in neuronal processes.

neuroscience↗

The protozoan commensal Tritrichomonas musculis is a natural adjuvant for mucosal IgA.

Immunoglobulin(Ig) A antibodies are the most abundant antibodies supporting mucosal immune homeostasis and host-microbiota interactions. Driven by gut commensal microbes, IgA-secreting plasma cells (PC) differentiate through T cell-dependent (Td) or T cell independent (Ti) mechanisms. While commensal bacteria within the microbiota are known for their ability to promote IgA, the role of non-bacterial commensal microbes on the induction of IgA remains elusive. Here, we demonstrate that permanent colonization with the protozoan commensal Tritrichomonas musculis (T.mu) promotes T-cell dependent, IgA class-switch recombination and intestinal accumulation of IgA-secreting PC. T.mu colonization specifically drives the expansion of T follicular helper cells and a unique ICOS+ non-Tfh cell population, accompanied by an increase in germinal center B cells. Blockade of ICOS:ICOSL co-stimulation or MHCII-expression on B cells are central for the induction of IgA following colonization by T.mu, implicating a previously underappreciated mode of IgA induction following protozoan commensal colonization. Finally, the commensal T.mu further improves the induction of IgA-secreting plasma cells and their peripheral dissemination, even against non-protozoan, orally ingested antigens, identifying T.mu as natural adjuvant for IgA. Collectively, these findings propose a previously unknown, protozoa-driven mode of IgA induction that supports intestinal immune homeostasis even against non-microbial antigens.

immunology↗

Nuclear autophagy interactome unveils WSTF as a constitutive nuclear inhibitor of inflammation

Macroautophagy (hereafter referred to as autophagy) degrades a variety of cellular components. A poorly understood area is autophagic degradation of nuclear substrates, or "nuclear autophagy". It remains unclear what can be degraded by autophagy from the mammalian nuclei. We began our study by investigating the nuclear binding partners of ATG8 family proteins that play important roles in recognizing autophagy substrates. We systematically evaluated the ATG8 nuclear interactome in primary human cells and in mouse brain, identifying hundreds of novel interactions. We continued our study by evaluating the nuclear proteomes of cellular senescence, a stable form of cell cycle arrest program associated with inflammation, in which nuclear autophagy is involved. Combined with the ATG8 nuclear interactome data, we identified WSTF, a component of the ISWI chromatin remodeling complex, as a novel substrate of nuclear autophagy. The degradation of WSTF, mediated by a direct interaction with the GABARAP isoform of ATG8, promotes chromatin accessibility of inflammatory genes and induces senescence-associated inflammation. Furthermore, WSTF directly binds the p65 subunit of NF-{kappa}B and inhibits its acetylation, thus blocking inflammatory gene expression in the setting of senescence, cancer, and pathogen infection. In addition, we show that loss of WSTF is required for the immuno-surveillance of oncogenic Ras in mouse liver; forced expression of WSTF inhibited tumor-suppressive inflammation and led to the development of liver tumors. Taken together, our study provides a global view of mammalian nuclear autophagy and reveals a novel nuclear inhibitor of inflammation implicated in diverse pathological contexts. Targeting WSTF may be broadly valuable as therapeutic intervention of inflammatory diseases.

cell biology↗

Heterogeneous and Surface-Catalyzed Amyloid Aggregation Monitored by Spatially Resolved Fluorescence and Single Molecule Microscopy

Amyloid aggregation is associated with many diseases and may also occur in therapeutic protein formulations. Addition of co-solutes is a key strategy to modulate the stability of proteins in pharmaceutical formulations and select inhibitors for drug design in the context of diseases. However, the heterogeneous nature of this multi-component system in terms of structures and mechanisms poses a number of challenges for the analysis of the chemical reaction. Combining a spatially resolved fluorescence approach with single molecule microscopy and machine learning approaches, we disentangle the different contributions from multiple species within a single aggregation experiment. Moreover, we link the presence of interfaces to the degree of heterogeneity of the aggregation kinetics and retrieve the rate constants and underlying mechanisms for single aggregation events, providing a general tool for a comprehensive analysis of self-assembly reactions. Table of Contents O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/510935v2_ufig1.gif" ALT="Figure 1"> View larger version (58K): org.highwire.dtl.DTLVardef@c678eaorg.highwire.dtl.DTLVardef@2c6decorg.highwire.dtl.DTLVardef@e4c2e4org.highwire.dtl.DTLVardef@b741aa_HPS_FORMAT_FIGEXP M_FIG C_FIG

biophysics↗

Highly synchronized cortical circuit dynamics mediate spontaneous pain

Cortical neural dynamics mediate information processing for the cerebral cortex, implicated in fundamental biological processes, such as vision and olfaction, in addition to neurological and psychiatric diseases. Spontaneous pain is a key feature of human neuropathic pain. Whether spontaneous pain pushes cortical network into an aberrant state, and if so, whether it can be brought back to a normal operating range to ameliorate pain are unknown. Using a clinically relevant mouse model of neuropathic pain with robust spontaneous pain-like behavior, we report that orofacial spontaneous pain activated a specific area within the primary somatosensory cortex (S1), displaying synchronized neural dynamics revealed by intravital two-photon calcium imaging. This synchronization was underpinned by local GABAergic interneuron hypoactivity. Pain-induced cortical synchronization could be attenuated by manipulating local S1 networks or clinically effective pain therapies. Specifically, both chemogenetic inhibition of pain-related c-Fos-expressing neurons, and selective activation of GABAergic interneurons, significantly attenuated S1 synchronization. Clinically effective pain therapies including carbamazepine and nerve root decompression could also dampen S1 synchronization. More importantly, restoring a normal range of neural dynamics, through attenuating pain-induced S1 synchronization, alleviated pain-like behavior. These results suggest spontaneous pain pushes S1 regional network into a synchronized state, whereas reversal of this synchronization alleviates pain.

neuroscience↗