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Yang, Y.

Publications and source records attributed to Yang, Y..

At least 793 records · Page 44Linked to original sources

High-resolution spatial multi-omics reveals cell-type specific nuclear compartments

The mammalian nucleus is compartmentalized by diverse subnuclear structures. These subnuclear structures, marked by nuclear bodies and histone modifications, are often cell-type specific and affect gene regulation and 3D genome organization1-3. Understanding nuclear organization requires identifying the molecular constituents of subnuclear structures and mapping their associations with specific genomic loci in individual cells, within complex tissues. Here, we introduce two-layer DNA seqFISH+, which allows simultaneous mapping of 100,049 genomic loci, together with nascent transcriptome for 17,856 genes and a diverse set of immunofluorescently labeled subnuclear structures all in single cells in cell lines and adult mouse cerebellum. Using these multi-omics datasets, we showed that repressive chromatin compartments are more variable by cell type than active compartments. We also discovered a single exception to this rule: an RNA polymerase II (RNAPII)-enriched compartment was associated with long, cell-type specific genes (> 200kb), in a manner distinct from nuclear speckles. Further, our analysis revealed that cell-type specific facultative and constitutive heterochromatin compartments marked by H3K27me3 and H4K20me3 are enriched at specific genes and gene clusters, respectively, and shape radial chromosomal positioning and inter-chromosomal interactions in neurons and glial cells. Together, our results provide a single-cell high-resolution multi-omics view of subnuclear compartments, associated genomic loci, and their impacts on gene regulation, directly within complex tissues.

genomics↗

A novel virus-induced cyclic dinucleotide, 2'3'-c-di-GMP, mediates STING-dependent antiviral immunity in Drosophila

In mammals, the enzyme cGAS senses the presence of cytosolic DNA and synthesizes the cyclic dinucleotide (CDN) 2'3'-cGAMP. This CDN binds to and activates the protein STING to trigger immunity. We recently discovered in the model organism Drosophila melanogaster two cGAS-like receptors (cGLRs) that activate STING-dependent antiviral immunity and can produce 3'2'-cGAMP, in addition to 2'3'-cGAMP. Here we explore CDN-mediated immunity in 14 different Drosophila species covering 50 million years of evolution and report that 2'3'-cGAMP and 3'2'-cGAMP fail to control infection by Drosophila C virus in D. serrata, D. sechellia and D. mojavensis. Using an accurate and sensitive mass spectrometry method, we discover an unexpected diversity of CDNs produced in a cGLR-dependent manner in response to viral infection in D. melanogaster, including a novel CDN, 2'3'-c-di-GMP. We show that 2'3'-c-di-GMP is the most potent STING agonist identified so far in D. melanogaster and that this molecule also activates a strong antiviral transcriptional response in D. serrata. Our results shed light on the evolution of cGLRs in flies and provide a basis for the understanding of the function and regulation of this emerging family of PRRs in animal innate immunity.

immunology↗

The landscape of tolerated genetic variation in humans and primates

Personalized genome sequencing has revealed millions of genetic differences between individuals, but our understanding of their clinical relevance remains largely incomplete. To systematically decipher the effects of human genetic variants, we obtained whole genome sequencing data for 809 individuals from 233 primate species, and identified 4.3 million common protein-altering variants with orthologs in human. We show that these variants can be inferred to have non-deleterious effects in human based on their presence at high allele frequencies in other primate populations. We use this resource to classify 6% of all possible human protein-altering variants as likely benign and impute the pathogenicity of the remaining 94% of variants with deep learning, achieving state-of-the-art accuracy for diagnosing pathogenic variants in patients with genetic diseases. One Sentence SummaryDeep learning classifier trained on 4.3 million common primate missense variants predicts variant pathogenicity in humans.

genomics↗

Analyzing bivariate cross-trait genetic architecture in GWAS summary statistics with the BIGA cloud computing platform

As large-scale biobanks provide increasing access to deep phenotyping and genomic data, genome-wide association studies (GWAS) are rapidly uncovering the genetic architecture behind various complex traits and diseases. GWAS publications typically make their summary-level data (GWAS summary statistics) publicly available, enabling further exploration of genetic overlaps between phenotypes gathered from different studies and cohorts. However, systematically analyzing high-dimensional GWAS summary statistics for thousands of phenotypes can be both logistically challenging and computationally demanding. In this paper, we introduce BIGA (https://bigagwas.org/), a website that aims to offer unified data analysis pipelines and processed data resources for cross-trait genetic architecture analyses using GWAS summary statistics. We have developed a framework to implement statistical genetics tools on a cloud computing platform, combined with extensive curated GWAS data resources. Through BIGA, users can upload data, submit jobs, and share results, providing the research community with a convenient tool for consolidating GWAS data and generating new insights.

genetics↗

Phylogenomic Analyses Reveal Widespread Gene Flow During the Early Radiation of Oaks and Relatives (Fagaceae: Quercoideae)

AO_SCPLOWBSTRACTC_SCPLOWOaks (Quercus), one of the most species-rich and ecologically dominant woody plant clades in the Northern Hemisphere, are well known for their propensity to hybridize and form syngameons, complexes where alleles are readily exchanged among closely related species. While hybridization has been extensively studied towards the tips of the oak phylogeny, the extent, timeline, and evolutionary scenarios of hybridization during the early radiation of oaks and related genera (Quercoideae) remain poorly known. Using an expansive new dataset of nuclear and chloroplast sequences (including up to 431 spp.), we conducted a multifaceted phylogenomic investigation of Quercus aimed at characterizing gene-tree and cytonuclear (chloroplast-nuclear) discordance and identifying ancient reticulation in the early evolution of the group. We document extensive nuclear gene-tree and cytonuclear discordance at deep nodes in Quercus and Quercoideae, with Quercus recovered as non-monophyletic in the chloroplast phylogeny. Analyses recovered clear signatures of gene flow against a backdrop of incomplete lineage sorting, with gene flow most prevalent among major lineages of Quercus and Quercoideae during their initial radiation, dated to the early-middle Eocene. Ancestral reconstructions including fossil data suggest that the ancestors of Castanea+Castanopsis, Lithocarpus, and the Old World oak clade co-occurred in North America and Eurasia, while the ancestors of Chrysolepis, Notholithocarpus, and the New World oak clade co-occurred in North America, offering ample opportunity for hybridization in each region. Following this initial phase of radiation and reticulation, we detected multiple niche shifts in Quercus and other Quercoideae genera that likely facilitated their expansion into new habitats arising from post-Eocene climatic changes. Our study shows that hybridization--perhaps in the form of ancient syngameons similar to those seen today--has been a common and important process throughout the evolutionary history of oaks and their close relatives.

evolutionary biology↗

Novel discovery of a lymphatic bridge connecting Schlemm's canal to limbal and conjunctival lymphatic pathway

PurposeSchlemms canal (SC) is a critical structure regulating aqueous humor (AH) drainage and intraocular pressure (IOP). It is known that in the conventional outflow pathway, AH flows from SC to episcleral veins. We recently reported a high-resolution three-dimensional (3D) imaging technology for intact eyeballs, SC and ocular surface. Using this advanced technology, we herein report the discovery of a new structure, termed lymphatic bridge, that directly connects SC to the limbal and conjunctival lymphatic pathway. Further investigation on this novel outflow pathway may provide new mechanisms and therapeutic approaches for glaucoma. MethodsAs reported previously, intact eyeballs were harvested from Prox-1-GFP (green fluorescent protein) mice and processed by a tissue clearing technique with CLARITY. Samples were immunolabeled with specific antibodies for CD31 (pan-endothelial marker) and LYVE-1 (lymphatic vessel endothelial hyaluronan receptor-1) and imaged by light-sheet fluorescent microscopy. The limbal areas were examined to locate connecting channels between SC and limbal and conjunctival lymphatic vessels. Moreover, in vivo anterior chamber dye injection was performed with Texas Red dextran for functional analysis on AH outflow. ResultsA novel lymphatic bridge structure that expressed both Prox-1 and LYVE-1 was discovered between the SC and limbal lymphatic vessels connected with conjunctival lymphatic pathway. Results from the anterior chamber dye injection showed AH drainage into the conjunctival lymphatic outflow pathway. ConclusionsThis study provides the first evidence on the direct connection between SC and limbal and conjunctival lymphatic pathway. This new pathway is distinctive from the conventional episcleral vein pathway and merits further investigation.

physiology↗

Novel Anammox Bacteria Discovered in the Untapped Subsurface Aquifers

Anaerobic ammonium-oxidation (anammox) reaction is a crucial microbial nitrogen (N) transformation process contributing to the global N cycling. The currently known anammox bacteria are affiliated with two families, the marine Ca. Scalinduaceae and the freshwater Ca. Brocadiaceae, in the Planctomycetes. Here we report a discovery of new groups of anammox bacteria consisting of two new orders, two new families, and six new genera within the class Candidatus Brocadiia, all from geochemically distinct aquifer systems. Up to 25 high-quality metagenome-assembled genomes (MAGs) equipped with the core anammox metabolisms were recovered from 13 metagenomic datasets of aquifers and dominated the anammox bacterial communities in distinct aquifers unexpectedly. The comparatively smaller genome size (< 2.6 Mb) and higher coding density (> 85%) likely confer the survival advantage of them by reducing the energy consumption in cell replication and maintenance to increase the nutrient acquisition efficiency in the typically oligotrophic aquifers. Overall, the highly diversity of novel anammox bacterial lineages in aquifer systems largely expands our knowledge of the taxonomic diversity of anammox bacteria and highlights their global importance in aquifer N cycling.

microbiology↗

Massive expansion of the pig gut virome based on global metagenomic mining

The pig gut virome plays a crucial role in the gut microbial ecosystem of pigs, yet a comprehensive reference database is still lacking. To address this gap, we established the Pig Virome Database (PVD) of the gut that comprises 5,566,804 viral contig sequences from 4,650 publicly available gut metagenomic samples using a pipeline named "metav" developed in this study. The majority of viral operational taxonomic units (vOTUs) were identified as Caudoviricetes (65.36%). By clustering sequences, we identified 48,299 vOTU genomes, of which 92.83% were not found in existing major databases. The PVD database contains a total of 18,161,503 protein-coding genes that can be used to explore the functional potential of the pig gut virome. Our study showed that the PVD can improve the detection of viruses that carry antibiotic/metal resistance genes, mobile genetic elements, virulence factor genes, and quorum sensing systems. These findings highlight the extensive diversity of viruses in the pig gut and provide detailed insight into host-virus interactions.

microbiology↗

Contigs directed gene annotation (ConDiGA) for accurate protein sequence database construction in metaproteomics

Microbiota are closely associated to human health and disease. Metaproteomics can provide a direct means to identify microbial proteins in microbiota for compositional and functional characterization. However, in-depth and accurate metaproteomics is still limited due to the extreme complexity and high diversity of microbiota samples. One of the main challenges is constructing a protein sequence database that best fits the microbiota sample. Herein, we proposed an accurate taxonomic annotation pipeline from metagenomic data for deep metaproteomic coverage, namely contigs directed gene annotation (ConDiGA). We mixed 12 known bacterial species to derive a synthetic microbial community to benchmark metagenomic and metaproteomic pipelines. With the optimized taxonomic annotation strategy by ConDiGA, we built a protein sequence database from the metagenomic data for metaproteomic analysis and identified about 12,000 protein groups, which was very close to the result obtained with the reference proteome protein sequence database of the 12 species. We also demonstrated the practicability of the method in real fecal samples, achieved deep proteome coverage of human gut microbiome, and compared the function and taxonomy of gut microbiota at metagenomic level and metaproteomic level. Our study can tackle the current taxonomic annotation reliability problem in metagenomics-derived protein sequence database for metaproteomics. The unique dataset of metagenomic and the metaproteomic data of the 12 bacterial species is publicly available as a standard benchmarking sample for evaluating various analysis pipelines. The code of ConDiGA is open access at GitHub for the analysis of real microbiota samples.

bioinformatics↗

Migratory herbivorous waterfowl couple the seed wave and the green wave during spring migration

East Asian herbivorous waterfowl intensively use farmland in spring, next to their natural habitat. Accordingly, they might have expanded their migration strategy from merely tracking the green wave of newly emerging vegetation to also incorporating the availability of post-harvest agricultural seeds (here dubbed the seed wave). However, if and how waterfowl use multiple food resources to time their seasonal migration is still unknown. We test this migration strategy using 167 spring migration tracks of five East Asian herbivorous waterfowl species and mixed-effect resource selection function models. We find all study species arrive at their core stopover sites in the Northeast China Plain after agricultural seeds become available, extend their stay after spring vegetation emerges, and arrive at breeding sites around the emergence of vegetation. Moreover, the cue used in exploiting the availability of both food resources varies in different regions and among species. At the core stopover sites, larger-bodied species use the seed wave and smaller-bodied ones adopt the green wave. At the breeding sites, the former follow the green wave, and the latter track the snow-free time. Our findings suggest that waterfowl track multiple resource waves to finetune their migration, highlighting new opportunities for conservation.

ecology↗

Endothelial Nitric Oxide Synthase Regulates Lymphatic Valve Specification By Controlling β-catenin Signaling During Embryogenesis

ObjectiveLymphatic valves play a critical role in ensuring unidirectional lymph transport. Loss of lymphatic valves or dysfunctional valves are associated with several diseases including lymphedema, lymphatic malformations, obesity, and ileitis. Lymphatic valves first develop during embryogenesis in response to mechanotransduction signaling pathways triggered by oscillatory lymph flow. In blood vessels, eNOS (gene name: Nos3) is a well characterized shear stress signaling effector, but its role in lymphatic valve development remains unexplored. Approach and ResultsWe used global Nos3-/- mice and cultured hdLECs to investigate the role of eNOS in lymphatic valve development, which requires oscillatory shear stress signaling. Our data reveal a 45% reduction in lymphatic valve specification cell clusters and that loss of eNOS protein inhibited activation of {beta}-catenin and its nuclear translocation. Genetic knockout or knockdown of eNOS led to downregulation of {beta}-catenin target proteins in vivo and in vitro. However, pharmacological inhibition of NO production did not reproduce these effects. Coimmunoprecipitation experiments reveal that eNOS forms a complex with {beta}-catenin and their association is enhanced by oscillatory shear stress. Finally, genetic ablation of the Foxo1 gene enhanced FOXC2 expression and rescued the loss of valve specification in the eNOS knockouts. ConclusionIn conclusion, we demonstrate a novel, nitric oxide-independent role for eNOS in regulating lymphatic valve specification and propose a mechanism by which eNOS forms a complex with {beta}-catenin to regulate its nuclear translocation and thereby transcriptional activity.

developmental biology↗

Amoeboid cells undergo durotaxis with soft end polarized NMIIA

Cell migration towards stiff substrates has been coined as durotaxis and implicated in development, wound healing and cancer, where complex interplays between immune and non-immune cells are present. Compared to the emerging mechanisms underlying the strongly adhesive mesenchymal durotaxis, little is known about whether immune cells - migrating in amoeboid mode - could follow mechanical cues. Here we develop an imaging-based confined migration device with stiffness gradient. By tracking live cell trajectory and analyzing the directionality of T cells and neutrophils, we observe that amoeboid cells can durotax. We further delineate the underlying mechanism to involve non-muscle myosin IIA (NMIIA) polarization towards the soft-matrix-side but may not require differential actin flow up- or down-stiffness gradient. Using the protista Dictyostelium, we demonstrate the evolutionary conservation of amoeboid durotaxis. Finally, these experimental phenomena are theoretically captured by an active gel model capable of mechanosensing. Collectively, these results may shed new lights on immune surveillance and recently identified confined migration of cancer cells, within the mechanically inhomogeneous tumor microenvironment or the inflamed fibrotic tissues.

cell biology↗

Single-cell RNA-sequencing identifies a novel subset of CD9+ reparative macrophages modulated by CCN2 derived from Nlrx1 deficient cardiomyocytes in the infarcted heart

RationaleNlrx1, a pattern recognition receptor belonging to the NLR family, is highly expressed in the heart and is significantly increased after myocardial infarction in vivo, however, the role of Nlrx1 in post-infarction inflammation and healing is poorly understood. Although the effects of infiltrating macrophages on survival of cardiomyocytes and healing of injured hearts have been intensely studied, whether or not and how surviving cardiomyocytes might influence the phenotype and function of macrophages in the infarcted hearts was largely unexplored. ObjectiveTo investigate the role of Nlrx1 in post-infarction inflammation and healing and to dissect the underlying mechanism. Methods and resultsSingle cell RNA-sequencing of 23,805 cells isolated from infarcted hearts revealed 7 clusters of infarct macrophages including CCR2+, Isg+, Mki67+ proliferative, and LYVE1+ cardiac resident macrophages, and identified a novel subset of CD9+Il1rn+ macrophages, which were characterized by high expression of Cd9, Il1rn, Gpnmb and Spp1, and downregulation of proinflammatory cytokines and chemokines. CD9+Il1rn+ macrophages were largely found in infarcted hearts of Nlrx1KO mice, and were transcriptionally unique with reparative phenotype. Loss of Nlrx1 attenuated ventricular dysfunction and adverse remodeling, and decreased post-infarction mortality. Flow cytometry analysis showed markedly increased number of CD9+ macrophages and higher mean fluorescence intensity of CD9 in Nlrx1KO mice. RNA-seq analysis revealed that CD9+ macrophages of Nlrx1KO infarcted hearts exhibited a reparative and anti-inflammatory phenotype as featured by upregulation of wound healing-associated genes including CD9, Spp1 and Fn1, and downregulation of proinflammatory genes. Conditioned medium from Nlrx1 deficient cardiomyocytes upon hypoxia stimulation skewed macrophage polarization towards a reparative and inflammation-suppressed phenotype. Gain-and loss-of function of Nlrx1 combined with RNA-seq analysis identified CCN2, whose expression and secretion were significantly increased in Nlrx1 deficient cardiomyocytes upon hypoxia, as a cardiomyocytes-derived mediator responsible, at least partly, for reprograming macrophage towards a reparative phenotype. In vivo, CCN2 expression was markedly elevated in Nlrx1KO infarcted hearts. Moreover, exogenous CCN2 partially mediated macrophage transition towards a reparative phenotype. ConclusionsCD9+ IL1rn+ macrophages modulated by Nlrx1 deficient cardiomyocytes-derived CCN2, is a novel subset of reparative macrophages contributing to infarct healing. Inhibition of myocardial Nlrx1 and/or activation of CCN2 to boost CD9+ IL1rn+ reparative macrophages may represent new therapeutics for infarct healing following ischemic injury.

immunology↗

Single-cell transcriptome analysis reveals the cellular atlas of human intracranial aneurysm and highlights inflammation features associated with aneurysm rupture

Intracranial aneurysm (IA) is pouch-like pathological dilations of cerebral arteries, which often affects middle-aged people and culminates in life-threatening hemorrhagic stroke. A deeper knowledge of the cellular and gene expression perturbations in human IA tissue deepens our understanding of disease mechanisms and facilitates developing pharmacological targets for unruptured IA. In this study, 21,332 qualified cells were obtained from cell-sparse ruptured and unruptured human IA tissues and a detailed cellular profile was determined, including conventional endothelial cells, smooth muscle cells (SMC), fibroblasts and the newly identified pericytes. Notably, striking proportion of immune cells were identified in IA tissue, with the number of monocyte/macrophages and neutrophils being remarkably higher in ruptured IA. By leveraging external datasets and machine learning algorithms, a subset of macrophages characterized by high expression of CCL3 and CXCL3, and transcriptional activation of NF-{kappa}B and HIVEP2 was identified as the cell most associated with IA rupture. Further, the interactome of CCL3/CXCL3 macrophages disclosed their role in regulating vascular cell survival and orchestrating inflammation. In summary, this study illustrated the profile and interactions of vascular and immune cells in human IA tissue and the opportunities for targeting local chronic inflammation.

cell biology↗

Repurposing the Memory-promoting Meclofenoxate Hydrochloride as a Treatment for Parkinson's Disease through Integrative Multi-omics analysis

Parkinson s disease (PD) is a devastating neurodegenerative disorder with growing prevalence worldwide and, as yet, no effective treatment. Drug repurposing promises to be invaluable for the identification of novel therapeutics for the treatment of PD due to the associated shortened drug development time, fewer safety concerns, and reduced costs. Here, we compiled gene expression data from 1,231 healthy human brains and 357 PD patients across ethnicities, brain regions, Braak stages, and disease status. By integrating them with multiple-source PD-associated genomic data, we found a conserved PD-associated gene co-expression module, and its alignment with the CMAP database successfully identified 15 drug candidates. Among these, we selected meclofenoxate hydrochloride (MH) and sodium phenylbutyrate (SP) for experimental validation because they are capable of passing through the blood brain barrier. In primary neurons, MH was found to prevent the neuronal death and synaptic damage associated with PD and to reverse the abnormal mitochondrial metabolism caused by PD. In hippocampal tissues, MH and SP were found to prevent the destruction of mitochondria, to reduce lipid peroxidation and to protect dopamine synthesis by PET-CT examination, malondialdehyde (MAD) testing and glutathione (GSH) testing, and immunohistochemical tests. Finally, MH was found to have the ability to improve gait behavior, and reduce anhedonic and depressive-like behaviors that are characteristics of PD mice. Taken together, our findings support the contention that MH may have the potential to ameliorate PD by improving mitochondrial metabolism and brain function.

biochemistry↗

Beyond a PPR-RNA recognition code: Many aspects matter for the multi-targeting properties of RNA editing factor PPR56

The mitochondrial C-to-U RNA editing factor PPR56 of the moss Physcomitrium patens is an RNA-binding pentatricopeptide repeat protein equipped with a terminal DYW-type cytidine deaminase domain. Transferred into Escherichia coli, PPR56 works faithfully on its two native RNA editing targets, nad3eU230SL and nad4eU272SL, and also converts cytidines into uridines at over 100 off-targets in the bacterial transcriptome. Accordingly, PPR56 is attractive for detailed mechanistic studies in the heterologous bacterial setup, allowing for scoring differential RNA editing activities of many target and protein variants in reasonable time. Here, we report (i) on the effects of numerous individual and combined PPR56 protein and target modifications, (ii) on the spectrum of off-target C-to-U editing in the bacterial background transcriptome for PPR56 and two variants engineered for target re-direction and (iii) on combinations of targets in tandem or separately at the 5- and 3-ends of large mRNAs. The latter experimentation finds enhancement of RNA editing at weak targets in many cases, including cox3eU290SF as a new candidate mitogenome target. We conclude that C-to-U RNA editing can be much enhanced by transcript features also outside the region ultimately targeted by PPRs of a plant editing factor, possibly facilitated by its enrichment or scanning along transcripts.

molecular biology↗

Sex-specific age-related changes in glymphatic function assessed by resting-state functional magnetic resonance imaging

The glymphatic system that clears out brain wastes, such as amyloid-{beta} (A{beta}) and tau, through cerebrospinal fluid (CSF) flow may play an important role in aging and dementias. However, a lack of non-invasive tools to assess the glymphatic function in humans hindered the understanding of the glymphatic changes in healthy aging. The global infra-slow (<0.1 Hz) brain activity measured by the global mean resting-state fMRI signal (gBOLD) was recently found to be coupled by large CSF movements. This coupling has been used to measure the glymphatic process and found to correlate with various pathologies of Alzheimers disease (AD), including A{beta} pathology. Using resting-state fMRI data from a large group of 719 healthy aging participants, we examined the sex-specific changes of the gBOLD-CSF coupling, as a measure of glymphatic function, over a wide age range between 36-100 years old. We found that this coupling index remains stable before around age 55 and then starts to decline afterward, particularly in females. Menopause may contribute to the accelerated decline in females.

neuroscience↗

EsxB, EsxC and EsxD facilitate export of the antibacterialnuclease EsaD by the Staphylococcus aureus Type VII secretionsystem

The type VIIb protein secretion system (T7SSb) plays a role in interbacterial competition in Gram-positive Firmicute bacteria and secretes various toxic effector proteins. The mechanism of secretion and the roles of numerous conserved genes within T7SSb gene clusters remain unknown. EsaD is a nuclease toxin secreted by the Staphylococcus aureus T7SSb, which forms a complex with its cognate immunity protein, EsaG, and chaperone EsaE. Encoded upstream of EsaD are three small secreted proteins, EsxB, EsxC and EsxD. Here we show that EsxBCD bind to the transport domain of EsaD and function as EsaD export factors. We report the first structural information for a complete T7SSb substrate pre-secretion complex. Cryo-EM of the EsaDEG trimer and the EsaDEG-EsxBCD hexamer shows that incorporation of EsxBCD confers a conformation comprising a flexible globular cargo domain attached to a long narrow shaft that is likely to be crucial for efficient toxin export.

microbiology↗