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Liu, Z.

Publications and source records attributed to Liu, Z..

At least 667 records · Page 37Linked to original sources

Unraveling the causal genes and transcriptomic determinants of human telomere length

Telomere length (TL) shortening is a pivotal indicator of biological aging and is associated with many human diseases. The genetic determinates of human TL have been widely investigated, however, most existing studies were conducted based on adult tissues which are heavily influenced by lifetime exposure. Based on the analyses of terminal restriction fragment (TRF) length of telomere, individual genotypes, and gene expressions on 166 healthy placental tissues, we systematically interrogated TL-modulated genes and their potential functions. We found that placental TL is relatively longer across human tissues and which maintenance is mostly connected to genes responsible for alternative lengthening of telomeres. Trans-ancestral TL genome-wide association studies (GWASs) on 644,553 individuals identified 20 novel genetic associations and provided increased polygenic determination of human TL. Next, we integrated the powerful TL GWAS with placental expression quantitative trait locus (eQTL) mapping to prioritize 31 likely causal genes, among which 4 were functionally validated, including MMUT, RRM1, KIAA1429, and YWHAZ. Finally, modeling transcriptomic signatures and TRF-based TL improved the prediction performance of human TL. This study deepened our understanding of causal genes and transcriptomic determinants of human TL, promoting the mechanistic research on fine-grained TL regulation.

genetics↗

In vivo Tracing of the Ascending Vagal Projections to the Brain with Manganese Enhanced Magnetic Resonance Imaging

The vagus nerve, the primary neural pathway mediating brain-body interactions, plays an essential role in transmitting bodily signals to the brain. Despite its significance, our understanding of the detailed organization and functionality of vagal afferent projections remains incomplete. In this study, we utilized manganese-enhanced magnetic resonance imaging (MEMRI) as a non-invasive method for tracing vagal nerve projections to the brainstem in vivo and assessing their functional dependence on cervical vagus nerve stimulation (VNS). Manganese chloride solution was injected into the nodose ganglion of rats, and T1-weighted MRI scans were performed 12 and 24 hours post-injection. Our findings reveal that vagal afferent neurons can uptake and transport manganese ions, serving as a surrogate for calcium ions, to the nucleus tractus solitarius (NTS) in the brainstem. In the absence of VNS, we observed significant contrast enhancements of around 19 to 24% in the NTS ipsilateral to the injection side. Application of VNS for four hours further promoted nerve activity, leading to greater contrast enhancements of 40 to 43% in the NTS. These results underline the potential of MEMRI for high-resolution, activity-dependent tracing of vagal afferents, providing a valuable tool for the structural and functional assessment of the vagus nerve and its influence on brain activity.

neuroscience↗

m6A Demethylase FTO Stabilizes LINK-A to Exert Oncogenic Roles via MCM3-Mediated Cell Cycle Progression and HIF-1α Activation

RNA N6-methyladenosine (m6A) modification, balanced by methyltransferases and demethylases, has recently been shown to play critical roles in multiple cancers. However, the mechanism by which m6A modification regulates long noncoding RNA (lncRNA) stability and function during cancer progression remains unclear. Here, we show that m6A demethylase fat mass and obesity-associated protein (FTO) removes the m6A modification on long intergenic noncoding RNA for kinase activation (LINK-A) and stabilizes it to promote cell proliferation and cytotoxic chemotherapy resistance in esophageal squamous cell carcinoma (ESCC). Mechanistically, LINK-A enhances the interaction between minichromosome maintenance complex component 3 (MCM3) and cyclin-dependent kinase 1 (CDK1) to promote MCM3 phosphorylation by CDK1. MCM3 is a subunit of the hexameric protein complex and its phosphorylation facilitates loading of the MCM complex onto chromatin, which promotes cell cycle progression and subsequent cell proliferation. Meanwhile, LINK-A prevents the interaction of MCM3 and hypoxia-inducible factor 1 (HIF-1), abrogates MCM3-mediated transcriptional repression of HIF-1, and promotes glycolysis and chemoresistance of cancer cells. These results elucidate a mechanism whereby FTO-stabilized LINK-A plays oncogenic roles and present the FTO/LINK-A/MCM3/HIF-1 axis as a promising therapeutic target for ESCC.

cancer biology↗

scGREAT: Graph-based regulatory element analysis tool for single-cell multi-omics data

MotivationWith the development in single-cell multi-omics sequencing technology and data integration algorithms, we have entered the single-cell multi-omics era. Current multi-omics analysis algorithms failed to systematically dissect the heterogeneity within the datasets when inferring cis-regulatory events. Thus, there is a need for cis-regulatory element inferring algorithms that considers the cellular heterogeneity. ResultsHere, we propose scGREAT, a single-cell multi-omics regulatory state analysis Python package with a rapid graph-based correlation measurement L. The graph-based correlation method assigns each cell a local L index, pinpointing specific cell groups of certain regulatory states. Such single-cell resolved regulatory state information enables the heterogeneity analysis equipped in the package. Applying scGREAT to the 10X Multiome PBMC dataset, we demonstrated how it could help subcluster cell types, infer regulation-based pseudo-time trajectory, discover feature modules, and find cluster-specific regulatory gene-peak pairs. Besides, we showed that global L index, which is the average of all local L values, is a better replacement for Pearsons r in ruling out confounding regulatory relationships that are not of research interests. Availabilityhttps://github.com/ChaozhongLiu/scGREAT

bioinformatics↗

Reprogramming Intrahepatic Cholangiocarcinoma Immune Microenvironment by Chemotherapy and CTLA-4 Blockade Enhances Anti-PD1 Therapy

Intrahepatic cholangiocarcinoma (ICC) has limited therapeutic options and a dismal prognosis. Anti-PD-L1 immunotherapy combined with gemcitabine/cisplatin chemotherapy has recently shown efficacy in biliary tract cancers, but responses are seen only in a minority of patients. Here, we studied the roles of anti-PD1 and anti-CTLA-4 immune checkpoint blockade (ICB) therapies when combined with gemcitabine/cisplatin and the mechanisms of treatment benefit in orthotopic murine ICC models. We evaluated the effects of the combined treatments on ICC vasculature and immune microenvironment using flow cytometry analysis, immunofluorescence, imaging mass cytometry, RNA-sequencing, qPCR, and in vivo T-cell depletion and CD8+ T-cell transfer using orthotopic ICC models and transgenic mice. Combining gemcitabine/cisplatin with anti-PD1 and anti-CTLA-4 antibodies led to substantial survival benefits and reduction of morbidity in two aggressive ICC models, which were ICB-resistant. Gemcitabine/cisplatin treatment increased the frequency of tumor-infiltrating lymphocytes and normalized the ICC vessels, and when combined with dual CTLA-4/PD1 blockade, increased the number of activated CD8+Cxcr3+IFN-{gamma}+ T-cells. Depletion of CD8+ but not CD4+ T-cells compromised efficacy. Conversely, CD8+ T-cell transfer from Cxcr3-/- versus Cxcr3+/+ mice into Rag1-/- immunodeficient mice restored the anti-tumor effect of gemcitabine/cisplatin/ICB combination therapy. Finally, rational scheduling of the ICBs (anti-CTLA-4 "priming") with chemotherapy and anti-PD1 therapy achieved equivalent efficacy with continuous dosing while reducing overall drug exposure. In summary, gemcitabine/cisplatin chemotherapy normalizes vessel structure, increases activated T-cell infiltration, and enhances anti-PD1/CTLA-4 immunotherapy efficacy in aggressive murine ICC. This combination approach should be clinically tested to overcome resistance to current therapies in ICC patients. One Sentence SummaryImmune microenvironment reprogramming by chemotherapy and priming using CTLA-4 blockade render ICCs responsive to anti-PD-1 immunotherapy.

cancer biology↗

Single-cell transcriptomic landscape deciphers novel olfactory neuroblastoma subtypes and intratumoral heterogeneity

Olfactory neuroblastoma (ONB) is an uncommon malignant tumor known to originate from the olfactory epithelial. The complex tumor ecosystem of this pathology remained unclear. Here, we explored the cellular components with ONB tumors based on scRNA profiles of 96,325 single-cells derived from 10 tumors and 1 olfactory mucosa sample. We discovered 11 major cell types, including 6 immune cell, 3 stromal cell subtypes and epithelial cluster in the tumor microenvironment (TME), and identified 5 common expression programs from malignant epithelial cells. We analyzed subclusters of TME and the interactions among different cell types in the TME. An innovative three-classification of ONB was established via scRNA analysis. Markers for categorizing tumor samples into new subtypes were elucidated. Different responses towards certain chemotherapy regimens could be inferred according to the molecular features of three tumor types. Relative abundance of immunosuppressive TAMs indicated the benefits of immunotherapies targeting myeloid cells.

cancer biology↗

PolyAMiner-Bulk: A Machine Learning Based Bioinformatics Algorithm to Infer and Decode Alternative Polyadenylation Dynamics from bulk RNA-seq data

More than half of human genes exercise alternative polyadenylation (APA) and generate mRNA transcripts with varying 3 untranslated regions (UTR). However, current computational approaches for identifying cleavage and polyadenylation sites (C/PASs) and quantifying 3UTR length changes from bulk RNA-seq data fail to unravel tissue- and disease-specific APA dynamics. Here, we developed a next-generation bioinformatics algorithm and application, PolyAMiner-Bulk, that utilizes an attention-based machine learning architecture and an improved vector projection-based engine to infer differential APA dynamics accurately. When applied to earlier studies, PolyAMiner-Bulk accurately identified more than twice the number of APA changes in an RBM17 knockdown bulk RNA-seq dataset compared to current generation tools. Moreover, on a separate dataset, PolyAMiner-Bulk revealed novel APA dynamics and pathways in scleroderma pathology and identified differential APA in a gene that was identified as being involved in scleroderma pathogenesis in an independent study. Lastly, we used PolyAMiner-Bulk to analyze the RNA-seq data of post-mortem prefrontal cortexes from the ROSMAP data consortium and unraveled novel APA dynamics in Alzheimers Disease. Our method, PolyAMiner-Bulk, creates a paradigm for future alternative polyadenylation analysis from bulk RNA-seq data.

bioinformatics↗

Topological design principle for the robustness of necroptosis biphasic, emergent, and coexistent (BEC) dynamics

Biphasic dynamics, the variable-dependent ability to enhance or restrain biological function, is prevalent in natural systems. Accompanied by biphasic dynamics, necroptosis signaling dominated by RIP1 also appears emergent and coexistent dynamics. Here, we identify the RIP1-RIP3-C8 incoherent feedforward loop embedded with positive feedback of RIP3 to RIP1 is the core topology, and the scale-free feature of RIP3 peak value dictates necroptosis BEC dynamics. Entropy production is introduced to quantify the uncertainty of coexistent dynamics. RIP3 auto-phosphorylation is further determined as a complementary process for robustly attaining necroptosis BEC dynamics. Through screening all possible two- and three-node circuit topologies, a complete atlas of three-node circuit BEC dynamics is generated and only three minimal circuits emerge as robust solutions, proving incoherent feedforward loop is the core topology. Overall, through highlighting a finite set of circuits, this study yields guiding principles for mapping, modulating, and designing circuits for BEC dynamics in biological systems.

systems biology↗

Plant selection and ecological microhabitat drive domestications of shrub-associated microbiomes in a revegetated shrub ecosystem

Shrubs are used for revegetation of degraded dryland ecosystem worldwide and could recruit large numbers of microbes from the soil; however, the plant-associated microbiome assembly and the effect of plant introduction on the soil microbiomes are not fully understood. We detected shrub-associated microbes from five ecological microhabitats, including the leaves, litter, roots, rhizosphere, and root zone, across four xeric shrub plantations (Artemisia ordosica, Caragana korshinskii, Hedysarum mongolicum, and Salix psammophila). To detect the patterns of shrub-associated microbiome assembly, 16S and ITS2 rRNA gene sequencing was performed. PERMANOVA and differential abundance analysis demonstrated that changes in the bacterial and fungal communities were more dependent on the microhabitats rather than on the plant species, with distinct niche differentiation. Moreover, source tracking and nestedness analysis showed that shrub-associated bacteria were primarily derived from bulk soils and slightly pruned in different microhabitats; however, a similar pattern was not found for fungi. Furthermore, the surrounding zone of roots was a hotpot for microbial recruitments of revegetated shrubs. Null model analysis indicated that homogeneous selection of determinism dominated the bacterial communities, whereas dispersal limitation and undominated process of stochasticity drove the assembly of fungal communities. Our findings indicate that ecological microhabitat of revegetated shrublands was the main predictor of the bacterial and fungal compositional variances. This study will help advance our understanding of the mechanism underlying the plant-soil microbiome feedbacks during the initial plant-establishment period in a dryland ecosystem. Further, this work provides theoretical reference for establishment and sustainable management of shrublands in drylands.

microbiology↗

Activation-induced cytidine deaminase-based in vivo continuous evolution system enables rapid protein engineering

Directed evolution is a powerful tool to modify the properties of proteins. However, due to multi-round and stage combinations, directed evolution usually requires time- and labor-intensive manual intervention, which limits the efficiency of protein modification to some extent. Therefore, in vivo continuous evolution system is highly preferred because it can couple the multiple rounds and steps of direction evolution with the host growth cycle, leading to the advantages of effort-saving and accuracy. However, the existing types of this kind of systems can not meet the booming demand. Herein, this paper describes promoted Escherichia coli-assisted continuous evolution (PEACE) that allows for in vivo continuous evolution of target genes. This system polymorphisms the target gene by activation-induced cytidine deaminase-T7 RNA polymerase (AID-T7 PNAP) fusion protein, then it couples the enzymatic properties of desired variants with the expression of antitoxins to achieve efficient growth-coupled screen using the toxin-antitoxin system (TAS). In this study, T7 RNAP was finally employed for validation of PEACE system, and its specificity to the promoter was successfully altered. These results demonstrated the feasibility and further application potential of PEACE.

molecular biology↗

Anthracyclines inhibit SARS-CoV-2 infection

Vaccines and drugs are two effective medical interventions to mitigate SARS-CoV-2 infection. Three SARS-CoV-2 inhibitors, remdesivir, paxlovid, and molnupiravir, have been approved for treating COVID-19 patients, but more are needed, because each drug has its limitation of usage and SARS-CoV-2 constantly develops drug resistance mutations. In addition, SARS-CoV-2 drugs have the potential to be repurposed to inhibit new human coronaviruses, thus help to prepare for future coronavirus outbreaks. We have screened a library of microbial metabolites to discover new SARS-CoV-2 inhibitors. To facilitate this screening effort, we generated a recombinant SARS-CoV-2 Delta variant carrying the nano luciferase as a reporter for measuring viral infection. Six compounds were found to inhibit SARS-CoV-2 at the half maximal inhibitory concentration (IC50) below 1 M, including the anthracycline drug aclarubicin that markedly reduced viral RNA-dependent RNA polymerase (RdRp)-mediated gene expression, whereas other anthracyclines inhibited SARS-CoV-2 by activating the expression of interferon and antiviral genes. As the most commonly prescribed anti-cancer drugs, anthracyclines hold the promise of becoming new SARS-CoV-2 inhibitors. IMPORTANCEMicrobial metabolites are a rich source of bioactive molecules. The best examples are antibiotics and immunosuppressants that have transformed the practice of modern medicine and saved millions of lives. Recently, some microbial metabolites were reported to have antiviral activity, including the inhibition of Zika virus and Ebola virus. In this study, we discovered several microbial metabolites that effectively inhibit SARS-CoV-2 infection, including anthracyclines that have also been shown to inhibit other viruses including Ebola virus through enhancing interferon responses, which indicates potentially broad antiviral properties of these microbial metabolites and can lead to the discovery of pan-antiviral molecules.

microbiology↗

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↗

DPHL v2: An updated and comprehensive DIA pan-human assay library for quantifying more than 14,000 proteins.

A comprehensive pan-human spectral library is critical for biomarker discovery using mass spectrometry (MS)-based proteomics. DPHL v1, a previous pan-human library built from 1096 data-dependent acquisition (DDA) MS data of 16 human tissue types, allows quantifying 10,943 proteins. However, a major limitation of DPHL v1 is the lack of semi-tryptic peptides and protein isoforms, which are abundant in clinical specimens. Here, we generated DPHL v2 from 1608 DDA-MS data acquired using Orbitrap mass spectrometers. The data included 586 DDA-MS newly acquired from 17 tissue types, while 1022 files were derived from DPHL v1. DPHL v2 thus comprises data from 24 sample types, including several cancer types (lung, breast, kidney, and prostate cancer, among others). We generated four variants of DPHL v2 to include semi-tryptic peptides and protein isoforms. DPHL v2 was then applied to a publicly available colorectal cancer dataset with 286 DIA-MS files. The numbers of identified and significantly dysregulated proteins increased by at least 21.7% and 14.2%, respectively, compared with DPHL v1. Our findings show that the increased human proteome coverage of DPHL v2 provides larger pools of potential protein biomarkers.

bioinformatics↗

VHL Mutation Drives Human Clear Cell Renal Cell Carcinoma Progression Through PI3K/AKT-Dependent Cholesteryl Ester Accumulation

BackgroundCholesteryl ester (CE) accumulation in intracellular lipid droplets (LDs) is an essential signature of clear cell renal cell carcinoma (ccRCC), but its molecular mechanism and pathological significance remain elusive. MethodsEnabled by the label-free Raman spectromicroscopy, which integrated stimulated Raman scattering microscopy with confocal Raman spectroscopy on the same platform, we quantitatively analyzed LD distribution and composition at the single cell level in intact ccRCC cell and tissue specimens in situ without any processing or exogenous labeling. Since we found that commonly used ccRCC cell lines actually did not show the CE-rich signature, primary cancer cells were isolated from human tissues to retain the lipid signature of ccRCC with CE level as high as the original tissue, which offers a preferable cell model for the study of cholesterol metabolism in ccRCC. Moreover, we established a patient-derived xenograft (PDX) mouse model that retained the CE-rich phenotype of human ccRCC. FindingsSurprisingly, our results revealed that CE accumulation was induced by tumor suppressor VHL mutation, the most common mutation of ccRCC. Moreover, VHL mutation was found to promote CE accumulation by upregulating HIF and subsequent PI3K/AKT/mTOR/SREBPs pathway. Inspiringly, inhibition of cholesterol esterification remarkably suppressed ccRCC aggressiveness in vitro and in vivo with negligible toxicity, through the reduced membrane cholesterol-mediated downregulations of integrin and MAPK signaling pathways. InterpretationCollectively, our study improves current understanding of the role of CE accumulation in ccRCC and opens up new opportunities for treatment. FundingThis work was supported by National Natural Science Foundation of China (No. U23B2046 and No. 62027824), National Key R&D Program of China (No. 2023YFC2415500), Fundamental Research Funds for the Central Universities (No. YWF-22-L-547), PKU-Baidu Fund (No. 2020BD033), Peking University First Hospital Scientific and Technological Achievement Transformation Incubation Guidance Fund (No.2022CX02), and Beijing Municipal Health Commission (No. 2020-2Z-40713).

cancer biology↗

Development of Multiomics in situ Pairwise Sequencing (MiP-Seq) for Single-cell Resolution Multidimensional Spatial Omics

Delineating the spatial multiomics landscape will pave the way to understanding the molecular basis of physiology and pathology. However, current spatial omics technology development is still in its infancy. Here, we developed a high-throughput multiomics in situ pairwise sequencing (MiP-Seq) strategy to efficiently decipher multiplexed DNAs, RNAs, proteins, and small biomolecules at subcellular resolution. We delineated dynamic spatial gene profiles in the hypothalamus using MiP-Seq. Moreover, MiP-Seq was unitized to detect tumor gene mutations and allele-specific expression of parental genes and to differentiate sites with and without the m6A RNA modification at specific sites. MiP-Seq was combined with in vivo Ca2+ imaging and Raman imaging to obtain a spatial multiomics atlas correlated to neuronal activity and cellular biochemical fingerprints. Importantly, we proposed a "signal dilution strategy" to resolve the crowded signals that challenge the applicability of in situ sequencing. Together, our method improves spatial multiomics and precision diagnostics and facilitates analyses of cell function in connection with gene profiles.

molecular biology↗

Ultrasensitive Proteomics Depicted an In-depth Landscape for Mouse Embryo

In recent years, single-cell or low-input multi-omics techniques have brought a revolution in the study of pre-implantation embryo development. However, single-cell or low-input proteome research in this field is relatively underdeveloped, due to the limited source of mammalian embryo samples, the objective reality of high abundance zona pellucida proteins, and the lack of hypersensitive proteome technology. Here, a comprehensive solution of ultrasensitive proteome technology was developed for single-cell or low-input mouse embryos. Both deep coverage route and high-throughput route could significantly reduce the starting material and enhance the proteomic depth without any customized instrument. Using the deep coverage route, an average of 2,665 or 4,585 protein groups can be identified from 1 or 20 mouse zygotes respectively. Using the high-throughput route, 300 single mouse zygotes can be analysis in 8 days with an average of 2,371 proteins identified. With its popularization, we believe researchers can choose deep coverage or high-throughput technology routes according to their own conditions.

systems biology↗

Functionally dissecting claustrum along anterior-posterior axis in anxiety and higher sensitivity to cocaine

Adolescent cocaine exposure (ACE) induce anxiety and higher sensitivity to drug addiction during adulthood. Here, we show that the claustrum is crucial for control of these two distinct psychiatric disorders in ACE mice. In the process of anxiety test, the CaMKII-positive neurons in median portion of claustrum (MClaustrum) were obviously triggered, and chemogenetic suppressing these neurons efficiently reduced ACE-induced anxiety in adulthood. While, the CaMKII-positive neurons in anterior portion of claustrum (AClaustrum) were obviously activated in response to cocaine-induced conditioned place preference (CPP), and chemogenetic suppressing these neurons efficiently blocked cocaine CPP in ACE mice during adulthood. Our findings dissociating specific sub-portions of claustrum for drug-related anxiety and susceptibility of addiction, extending our understanding to diverse functions of claustrum subregions.

neuroscience↗

PanCanSurvPlot: A Large-scale Pan-cancer Survival Analysis Web Application

The identification of reliable tumor prognostic markers can help clinicians and researchers predict tumor development and patient survival outcomes more accurately, which plays a vital role in clinical diagnosis, treatment effectiveness assessment, and prognostic evaluation. Existing web tools supporting online survival analysis are gradually failing to meet the increasing demands of researchers in terms of the dataset size, richness of survival analysis methods, and diversity of customization features. Therefore, there is an urgent need for a large-scale, one-stop pan-cancer survival analysis web server. We developed PanCanSurvPlot (https://smuonco.shinyapps.io/PanCanSurvPlot/), a Shiny web tool that has incorporated a total of 215 cancer-related datasets from the GEO and TCGA databases, covering nearly 100,000 genes (mRNAs, miRNAs, and lncRNAs), approximately 45,000 samples, 51 different cancer types, and 13 different survival outcomes. The website also provides two cutoff methods based on median and optimal cutpoints. All survival analysis results from the log-rank test and univariate Cox regression are presented in a clear and straightforward summary table. Finally, users can customize color schemes and cutpoint levels to quickly obtain high-quality Kaplan-Meier survival plots that meet publication requirements.

cancer biology↗