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1.
Cell ; 187(8): 2010-2028.e30, 2024 04 11.
Article in English | MEDLINE | ID: mdl-38569542

ABSTRACT

Gut inflammation involves contributions from immune and non-immune cells, whose interactions are shaped by the spatial organization of the healthy gut and its remodeling during inflammation. The crosstalk between fibroblasts and immune cells is an important axis in this process, but our understanding has been challenged by incomplete cell-type definition and biogeography. To address this challenge, we used multiplexed error-robust fluorescence in situ hybridization (MERFISH) to profile the expression of 940 genes in 1.35 million cells imaged across the onset and recovery from a mouse colitis model. We identified diverse cell populations, charted their spatial organization, and revealed their polarization or recruitment in inflammation. We found a staged progression of inflammation-associated tissue neighborhoods defined, in part, by multiple inflammation-associated fibroblasts, with unique expression profiles, spatial localization, cell-cell interactions, and healthy fibroblast origins. Similar signatures in ulcerative colitis suggest conserved human processes. Broadly, we provide a framework for understanding inflammation-induced remodeling in the gut and other tissues.


Subject(s)
Colitis, Ulcerative , Colitis , Animals , Humans , Mice , Colitis/metabolism , Colitis/pathology , Colitis, Ulcerative/metabolism , Colitis, Ulcerative/pathology , Fibroblasts/metabolism , Fibroblasts/pathology , In Situ Hybridization, Fluorescence/methods , Inflammation/metabolism , Inflammation/pathology , Cell Communication , Gastrointestinal Tract/metabolism , Gastrointestinal Tract/pathology
2.
Cell ; 184(22): 5527-5540.e18, 2021 10 28.
Article in English | MEDLINE | ID: mdl-34644527

ABSTRACT

To secure phosphorus (P) from soil, most land plants use a direct phosphate uptake pathway via root hairs and epidermis and an indirect phosphate uptake pathway via mycorrhizal symbiosis. The interaction between these two pathways is unclear. Here, we mapped a network between transcription factors and mycorrhizal symbiosis-related genes using Y1H. Intriguingly, this gene regulatory network is governed by the conserved P-sensing pathway, centered on phosphate starvation response (PHR) transcription factors. PHRs are required for mycorrhizal symbiosis and regulate symbiosis-related genes via the P1BS motif. SPX-domain proteins suppress OsPHR2-mediated induction of symbiosis-related genes and inhibit mycorrhizal infection. In contrast, plants overexpressing OsPHR2 show improved mycorrhizal infection and are partially resistant to P-mediated inhibition of symbiosis. Functional analyses of network nodes revealed co-regulation of hormonal signaling and mycorrhizal symbiosis. This network deciphers extensive regulation of mycorrhizal symbiosis by endogenous and exogenous signals and highlights co-option of the P-sensing pathway for mycorrhizal symbiosis.


Subject(s)
Gene Regulatory Networks , Mycorrhizae/genetics , Mycorrhizae/physiology , Phosphates/deficiency , Symbiosis/genetics , Symbiosis/physiology , Base Sequence , Gene Expression Regulation, Plant , Mutation/genetics , Oryza/genetics , Oryza/microbiology , Phylogeny , Plant Proteins/genetics , Plant Proteins/metabolism , Promoter Regions, Genetic/genetics , Saccharomyces cerevisiae/metabolism , Two-Hybrid System Techniques
3.
Cell ; 183(4): 875-889.e17, 2020 11 12.
Article in English | MEDLINE | ID: mdl-33035453

ABSTRACT

Banyan trees are distinguished by their extraordinary aerial roots. The Ficus genus includes species that have evolved a species-specific mutualism system with wasp pollinators. We sequenced genomes of the Chinese banyan tree, F. microcarpa, and a species lacking aerial roots, F. hispida, and one wasp genome coevolving with F. microcarpa, Eupristina verticillata. Comparative analysis of the two Ficus genomes revealed dynamic karyotype variation associated with adaptive evolution. Copy number expansion of auxin-related genes from duplications and elevated auxin production are associated with aerial root development in F. microcarpa. A male-specific AGAMOUS paralog, FhAG2, was identified as a candidate gene for sex determination in F. hispida. Population genomic analyses of Ficus species revealed genomic signatures of morphological and physiological coadaptation with their pollinators involving terpenoid- and benzenoid-derived compounds. These three genomes offer insights into and genomic resources for investigating the geneses of aerial roots, monoecy and dioecy, and codiversification in a symbiotic system.


Subject(s)
Biological Evolution , Ficus/genetics , Genome, Plant , Pollination/physiology , Trees/genetics , Wasps/physiology , Animals , Chromosomes, Plant/genetics , DNA Transposable Elements/genetics , Female , Gene Expression Profiling , Gene Expression Regulation, Plant , Genes, Plant , Indoleacetic Acids/metabolism , Molecular Sequence Annotation , Phylogeny , Plant Roots/growth & development , Segmental Duplications, Genomic/genetics , Sex Chromosomes/genetics , Volatile Organic Compounds/analysis
4.
Nat Immunol ; 22(9): 1175-1185, 2021 09.
Article in English | MEDLINE | ID: mdl-34429546

ABSTRACT

Systematic characterizations of adipose regulatory T (Treg) cell subsets and their phenotypes remain uncommon. Using single-cell ATAC-sequencing and paired single-cell RNA and T cell receptor (TCR) sequencing to map mouse adipose Treg cells, we identified CD73hiST2lo and CD73loST2hi subsets with distinct clonal expansion patterns. Analysis of TCR-sharing data implied a state transition between CD73hiST2lo and CD73loST2hi subsets. Mechanistically, we revealed that insulin signaling occurs through a HIF-1α-Med23-PPAR-γ axis to drive the transition of CD73hiST2lo into a CD73loST2hi adipose Treg cell subset. Treg cells deficient in insulin receptor, HIF-1α or Med23 have decreased PPAR-γ expression that in turn promotes accumulation of CD73hiST2lo adipose Treg cells and physiological adenosine production to activate beige fat biogenesis. We therefore unveiled a developmental trajectory of adipose Treg cells and its dependence on insulin signaling. Our findings have implications for understanding the dynamics of adipose Treg cell subsets in aged and obese contexts.


Subject(s)
Adipose Tissue/immunology , Insulin Resistance/immunology , Insulin/metabolism , Receptor, Insulin/metabolism , T-Lymphocytes, Regulatory/immunology , 5'-Nucleotidase/genetics , 5'-Nucleotidase/metabolism , Adipose Tissue/cytology , Aging/immunology , Animals , Cells, Cultured , High-Throughput Nucleotide Sequencing , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Interleukin-1 Receptor-Like 1 Protein/genetics , Interleukin-1 Receptor-Like 1 Protein/metabolism , Male , Mediator Complex/metabolism , Mice , Mice, Inbred C57BL , Obesity/genetics , Obesity/immunology , PPAR gamma/metabolism , Receptors, Antigen, T-Cell/genetics , Signal Transduction/genetics , Signal Transduction/immunology , T-Lymphocytes, Regulatory/cytology
5.
Immunity ; 57(6): 1345-1359.e5, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38692280

ABSTRACT

Regulatory T (Treg) cells in epidydimal visceral adipose tissue (eVAT) of lean mice and humans regulate metabolic homeostasis. We found that constitutive or punctual depletion of eVAT-Treg cells reined in the differentiation of stromal adipocyte precursors. Co-culture of these precursors with conditional medium from eVAT-Treg cells limited their differentiation in vitro, suggesting a direct effect. Transcriptional comparison of adipocyte precursors, matured in the presence or absence of the eVAT-Treg-conditioned medium, identified the oncostatin-M (OSM) signaling pathway as a key distinction. Addition of OSM to in vitro cultures blocked the differentiation of adipocyte precursors, while co-addition of anti-OSM antibodies reversed the ability of the eVAT-Treg-conditioned medium to inhibit in vitro adipogenesis. Genetic depletion of OSM (specifically in Treg) cells or of the OSM receptor (specifically on stromal cells) strongly impaired insulin sensitivity and related metabolic indices. Thus, Treg-cell-mediated control of local progenitor cells maintains adipose tissue and metabolic homeostasis, a regulatory axis seemingly conserved in humans.


Subject(s)
Adipocytes , Cell Differentiation , Homeostasis , Insulin Resistance , T-Lymphocytes, Regulatory , Animals , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism , Humans , Mice , Adipocytes/metabolism , Cell Differentiation/immunology , Oncostatin M/metabolism , Signal Transduction , Intra-Abdominal Fat/metabolism , Intra-Abdominal Fat/cytology , Intra-Abdominal Fat/immunology , Stromal Cells/metabolism , Mice, Inbred C57BL , Coculture Techniques , Adipogenesis , Cells, Cultured , Male , Adipose Tissue/metabolism , Adipose Tissue/cytology , Culture Media, Conditioned/pharmacology
6.
Immunity ; 56(4): 829-846.e8, 2023 04 11.
Article in English | MEDLINE | ID: mdl-36822206

ABSTRACT

Specific microbial signals induce the differentiation of a distinct pool of RORγ+ regulatory T (Treg) cells crucial for intestinal homeostasis. We discovered highly analogous populations of microbiota-dependent Treg cells that promoted tissue regeneration at extra-gut sites, notably acutely injured skeletal muscle and fatty liver. Inflammatory meditators elicited by tissue damage combined with MHC-class-II-dependent T cell activation to drive the accumulation of gut-derived RORγ+ Treg cells in injured muscle, wherein they regulated the dynamics and tenor of early inflammation and helped balance the proliferation vs. differentiation of local stem cells. Reining in IL-17A-producing T cells was a major mechanism underlying the rheostatic functions of RORγ+ Treg cells in compromised tissues. Our findings highlight the importance of gut-trained Treg cell emissaries in controlling the response to sterile injury of non-mucosal tissues.


Subject(s)
Gastrointestinal Microbiome , Microbiota , Animals , Mice , T-Lymphocytes, Regulatory , Nuclear Receptor Subfamily 1, Group F, Member 3/genetics , Mice, Inbred C57BL
7.
Nature ; 629(8014): 1158-1164, 2024 May.
Article in English | MEDLINE | ID: mdl-38750355

ABSTRACT

Plant pattern-recognition receptors perceive microorganism-associated molecular patterns to activate immune signalling1,2. Activation of the pattern-recognition receptor kinase CERK1 is essential for immunity, but tight inhibition of receptor kinases in the absence of pathogen is crucial to prevent autoimmunity3,4. Here we find that the U-box ubiquitin E3 ligase OsCIE1 acts as a molecular brake to inhibit OsCERK1 in rice. During homeostasis, OsCIE1 ubiquitinates OsCERK1, reducing its kinase activity. In the presence of the microorganism-associated molecular pattern chitin, active OsCERK1 phosphorylates OsCIE1 and blocks its E3 ligase activity, thus releasing the brake and promoting immunity. Phosphorylation of a serine within the U-box of OsCIE1 prevents its interaction with E2 ubiquitin-conjugating enzymes and serves as a phosphorylation switch. This phosphorylation site is conserved in E3 ligases from plants to animals. Our work identifies a ligand-released brake that enables dynamic immune regulation.


Subject(s)
Oryza , Plant Immunity , Plant Proteins , Ubiquitin , Animals , Chitin/metabolism , Homeostasis , Ligands , Oryza/enzymology , Oryza/immunology , Oryza/metabolism , Oryza/microbiology , Phosphorylation , Plant Proteins/antagonists & inhibitors , Plant Proteins/immunology , Plant Proteins/metabolism , Ubiquitin/metabolism , Ubiquitin-Conjugating Enzymes/metabolism , Ubiquitin-Protein Ligases/antagonists & inhibitors , Ubiquitin-Protein Ligases/chemistry , Ubiquitin-Protein Ligases/metabolism , Ubiquitination , Phosphoserine/metabolism , Conserved Sequence
8.
Nature ; 615(7950): 87-93, 2023 03.
Article in English | MEDLINE | ID: mdl-36859582

ABSTRACT

Water resources sustainability in High Mountain Asia (HMA) surrounding the Tibetan Plateau (TP)-known as Asia's water tower-has triggered widespread concerns because HMA protects millions of people against water stress1,2. However, the mechanisms behind the heterogeneous trends observed in terrestrial water storage (TWS) over the TP remain poorly understood. Here we use a Lagrangian particle dispersion model and satellite observations to attribute about 1 Gt of monthly TWS decline in the southern TP during 2003-2016 to westerlies-carried deficit in precipitation minus evaporation (PME) from the southeast North Atlantic. We further show that HMA blocks the propagation of PME deficit into the central TP, causing a monthly TWS increase by about 0.5 Gt. Furthermore, warming-induced snow and glacial melt as well as drying-induced TWS depletion in HMA weaken the blocking of HMA's mountains, causing persistent northward expansion of the TP's TWS deficit since 2009. Future projections under two emissions scenarios verified by satellite observations during 2020-2021 indicate that, by the end of the twenty-first century, up to 84% (for scenario SSP245) and 97% (for scenario SSP585) of the TP could be afflicted by TWS deficits. Our findings indicate a trajectory towards unsustainable water systems in HMA that could exacerbate downstream water stress.


Subject(s)
Altitude , Climate Change , Desiccation , Forecasting , Water Supply , Humans , Asia , Climate Change/statistics & numerical data , Water Supply/statistics & numerical data , Tibet , Freezing , Snow , Satellite Imagery , Rain , Atlantic Ocean , Ice Cover , Conservation of Water Resources
9.
Nature ; 621(7979): 499-505, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37674075

ABSTRACT

Two-dimensional (2D) van der Waals (vdW) heterostructures have attracted considerable attention in recent years1-5. The most widely used method of fabrication is to stack mechanically exfoliated micrometre-sized flakes6-18, but this process is not scalable for practical applications. Despite thousands of 2D materials being created, using various stacking combinations1-3,19-21, hardly any large 2D superconductors can be stacked intact into vdW heterostructures, greatly restricting the applications for such devices. Here we report a high-to-low temperature strategy for controllably growing stacks of multiple-layered vdW superconductor heterostructure (vdWSH) films at a wafer scale. The number of layers of 2D superconductors in the vdWSHs can be precisely controlled, and we have successfully grown 27 double-block, 15 triple-block, 5 four-block and 3 five-block vdWSH films (where one block represents one 2D material). Morphological, spectroscopic and atomic-scale structural analyses reveal the presence of parallel, clean and atomically sharp vdW interfaces on a large scale, with very little contamination between neighbouring layers. The intact vdW interfaces allow us to achieve proximity-induced superconductivity and superconducting Josephson junctions on a centimetre scale. Our process for making multiple-layered vdWSHs can easily be generalized to other situations involving 2D materials, potentially accelerating the design of next-generation functional devices and applications22-24.

10.
Nature ; 619(7968): 73-77, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37316660

ABSTRACT

High-entropy alloy nanoparticles (HEA-NPs) show great potential as functional materials1-3. However, thus far, the realized high-entropy alloys have been restricted to palettes of similar elements, which greatly hinders the material design, property optimization and mechanistic exploration for different applications4,5. Herein, we discovered that liquid metal endowing negative mixing enthalpy with other elements could provide a stable thermodynamic condition and act as a desirable dynamic mixing reservoir, thus realizing the synthesis of HEA-NPs with a diverse range of metal elements in mild reaction conditions. The involved elements have a wide range of atomic radii (1.24-1.97 Å) and melting points (303-3,683 K). We also realized the precisely fabricated structures of nanoparticles via mixing enthalpy tuning. Moreover, the real-time conversion process (that is, from liquid metal to crystalline HEA-NPs) is captured in situ, which confirmed a dynamic fission-fusion behaviour during the alloying process.

11.
Nature ; 623(7987): 633-642, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37938770

ABSTRACT

Trimethylation of histone H3 lysine 9 (H3K9me3) is crucial for the regulation of gene repression and heterochromatin formation, cell-fate determination and organismal development1. H3K9me3 also provides an essential mechanism for silencing transposable elements1-4. However, previous studies have shown that canonical H3K9me3 readers (for example, HP1 (refs. 5-9) and MPP8 (refs. 10-12)) have limited roles in silencing endogenous retroviruses (ERVs), one of the main transposable element classes in the mammalian genome13. Here we report that trinucleotide-repeat-containing 18 (TNRC18), a poorly understood chromatin regulator, recognizes H3K9me3 to mediate the silencing of ERV class I (ERV1) elements such as LTR12 (ref. 14). Biochemical, biophysical and structural studies identified the carboxy-terminal bromo-adjacent homology (BAH) domain of TNRC18 (TNRC18(BAH)) as an H3K9me3-specific reader. Moreover, the amino-terminal segment of TNRC18 is a platform for the direct recruitment of co-repressors such as HDAC-Sin3-NCoR complexes, thus enforcing optimal repression of the H3K9me3-demarcated ERVs. Point mutagenesis that disrupts the TNRC18(BAH)-mediated H3K9me3 engagement caused neonatal death in mice and, in multiple mammalian cell models, led to derepressed expression of ERVs, which affected the landscape of cis-regulatory elements and, therefore, gene-expression programmes. Collectively, we describe a new H3K9me3-sensing and regulatory pathway that operates to epigenetically silence evolutionarily young ERVs and exert substantial effects on host genome integrity, transcriptomic regulation, immunity and development.


Subject(s)
Endogenous Retroviruses , Gene Silencing , Histones , Intracellular Signaling Peptides and Proteins , Lysine , Retroelements , Animals , Humans , Mice , Chromatin/genetics , Chromatin/metabolism , Co-Repressor Proteins/metabolism , Endogenous Retroviruses/genetics , Epigenesis, Genetic , Gene Expression Profiling , Genome/genetics , Histone Deacetylases/metabolism , Histones/metabolism , Intracellular Signaling Peptides and Proteins/chemistry , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Lysine/metabolism , Methylation , Protein Domains , Retroelements/genetics , Terminal Repeat Sequences/genetics , Animals, Newborn , Cell Line
12.
Nature ; 2023 Apr 05.
Article in English | MEDLINE | ID: mdl-37019149

ABSTRACT

SARS-CoV-2, the causative agent of COVID-19, emerged in December 2019. Its origins remain uncertain. It has been reported that a number of the early human cases had a history of contact with the Huanan Seafood Market. Here we present the results of surveillance for SARS-CoV-2 within the market. From January 1st 2020, after closure of the market, 923 samples were collected from the environment. From 18th January, 457 samples were collected from 18 species of animals, comprising of unsold contents of refrigerators and freezers, swabs from stray animals, and the contents of a fish tank. Using RT-qPCR, SARS-CoV-2 was detected in 73 environmental samples, but none of the animal samples. Three live viruses were successfully isolated. The viruses from the market shared nucleotide identity of 99.99% to 100% with the human isolate HCoV-19/Wuhan/IVDC-HB-01/2019. SARS-CoV-2 lineage A (8782T and 28144C) was found in an environmental sample. RNA-seq analysis of SARS-CoV-2 positive and negative environmental samples showed an abundance of different vertebrate genera at the market. In summary, this study provides information about the distribution and prevalence of SARS-CoV-2 in the Huanan Seafood Market during the early stages of the COVID-19 outbreak.

13.
Nature ; 618(7964): 374-382, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37225988

ABSTRACT

Cancer alters the function of multiple organs beyond those targeted by metastasis1,2. Here we show that inflammation, fatty liver and dysregulated metabolism are hallmarks of systemically affected livers in mouse models and in patients with extrahepatic metastasis. We identified tumour-derived extracellular vesicles and particles (EVPs) as crucial mediators of cancer-induced hepatic reprogramming, which could be reversed by reducing tumour EVP secretion via depletion of Rab27a. All EVP subpopulations, exosomes and principally exomeres, could dysregulate hepatic function. The fatty acid cargo of tumour EVPs-particularly palmitic acid-induced secretion of tumour necrosis factor (TNF) by Kupffer cells, generating a pro-inflammatory microenvironment, suppressing fatty acid metabolism and oxidative phosphorylation, and promoting fatty liver formation. Notably, Kupffer cell ablation or TNF blockade markedly decreased tumour-induced fatty liver generation. Tumour implantation or pre-treatment with tumour EVPs diminished cytochrome P450 gene expression and attenuated drug metabolism in a TNF-dependent manner. We also observed fatty liver and decreased cytochrome P450 expression at diagnosis in tumour-free livers of patients with pancreatic cancer who later developed extrahepatic metastasis, highlighting the clinical relevance of our findings. Notably, tumour EVP education enhanced side effects of chemotherapy, including bone marrow suppression and cardiotoxicity, suggesting that metabolic reprogramming of the liver by tumour-derived EVPs may limit chemotherapy tolerance in patients with cancer. Our results reveal how tumour-derived EVPs dysregulate hepatic function and their targetable potential, alongside TNF inhibition, for preventing fatty liver formation and enhancing the efficacy of chemotherapy.


Subject(s)
Extracellular Vesicles , Fatty Acids , Fatty Liver , Liver , Pancreatic Neoplasms , Animals , Mice , Cytochrome P-450 Enzyme System/genetics , Extracellular Vesicles/metabolism , Fatty Acids/metabolism , Fatty Liver/drug therapy , Fatty Liver/etiology , Fatty Liver/metabolism , Fatty Liver/prevention & control , Liver/metabolism , Liver/pathology , Liver/physiopathology , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/pathology , Tumor Microenvironment , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Tumor Necrosis Factor-alpha/metabolism , Liver Neoplasms/secondary , Humans , Inflammation/metabolism , Palmitic Acid/metabolism , Kupffer Cells , Oxidative Phosphorylation , rab27 GTP-Binding Proteins/deficiency
14.
Cell ; 152(1-2): 82-96, 2013 Jan 17.
Article in English | MEDLINE | ID: mdl-23313552

ABSTRACT

The induction of pluripotency or trans-differentiation of one cell type to another can be accomplished with cell-lineage-specific transcription factors. Here, we report that repression of a single RNA binding polypyrimidine-tract-binding (PTB) protein, which occurs during normal brain development via the action of miR-124, is sufficient to induce trans-differentiation of fibroblasts into functional neurons. Besides its traditional role in regulated splicing, we show that PTB has a previously undocumented function in the regulation of microRNA functions, suppressing or enhancing microRNA targeting by competitive binding on target mRNA or altering local RNA secondary structure. A key event during neuronal induction is the relief of PTB-mediated blockage of microRNA action on multiple components of the REST complex, thereby derepressing a large array of neuronal genes, including miR-124 and multiple neuronal-specific transcription factors, in nonneuronal cells. This converts a negative feedback loop to a positive one to elicit cellular reprogramming to the neuronal lineage.


Subject(s)
Cell Differentiation , Fibroblasts/cytology , MicroRNAs/genetics , Neurons/cytology , Polypyrimidine Tract-Binding Protein/metabolism , Animals , Cell Line , Cell Lineage , Down-Regulation , Humans , Mice , MicroRNAs/metabolism , Polypyrimidine Tract-Binding Protein/genetics , RNA Splicing , Synapses
15.
N Engl J Med ; 391(9): 821-831, 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-39231344

ABSTRACT

BACKGROUND: In June 2019, a patient presented with persistent fever and multiple organ dysfunction after a tick bite at a wetland park in Inner Mongolia. Next-generation sequencing in this patient revealed an infection with a previously unknown orthonairovirus, which we designated Wetland virus (WELV). METHODS: We conducted active hospital-based surveillance to determine the prevalence of WELV infection among febrile patients with a history of tick bites. Epidemiologic investigation was performed. The virus was isolated, and its infectivity and pathogenicity were investigated in animal models. RESULTS: WELV is a member of the orthonairovirus genus in the Nairoviridae family and is most closely related to the tickborne Hazara orthonairovirus genogroup. Acute WELV infection was identified in 17 patients from Inner Mongolia, Heilongjiang, Jilin, and Liaoning, China, by means of reverse-transcriptase-polymerase-chain-reaction assay. These patients presented with nonspecific symptoms, including fever, dizziness, headache, malaise, myalgia, arthritis, and back pain and less frequently with petechiae and localized lymphadenopathy. One patient had neurologic symptoms. Common laboratory findings were leukopenia, thrombocytopenia, and elevated d-dimer and lactate dehydrogenase levels. Serologic assessment of convalescent-stage samples obtained from 8 patients showed WELV-specific antibody titers that were 4 times as high as those in acute-phase samples. WELV RNA was detected in five tick species and in sheep, horses, pigs, and Transbaikal zokors (Myospalax psilurus) sampled in northeastern China. The virus that was isolated from the index patient and ticks showed cytopathic effects in human umbilical-vein endothelial cells. Intraperitoneal injection of the virus resulted in lethal infections in BALB/c, C57BL/6, and Kunming mice. The Haemaphysalis concinna tick is a possible vector that can transovarially transmit WELV. CONCLUSIONS: A newly discovered orthonairovirus was identified and shown to be associated with human febrile illnesses in northeastern China. (Funded by the National Natural Science Foundation of China and the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences.).


Subject(s)
Fever , Nairovirus , Tick Bites , Adult , Aged , Animals , Female , Humans , Male , Mice , Middle Aged , Young Adult , Antibodies, Viral/blood , China/epidemiology , Fever/diagnosis , Fever/epidemiology , Fever/virology , Nairovirus/genetics , Nairovirus/isolation & purification , Nairovirus/pathogenicity , Phylogeny , Tick Bites/complications , Tick Bites/virology , Prevalence , Disease Models, Animal , Sheep , Horses , Swine , Infant , Child, Preschool , Child , Adolescent , Aged, 80 and over
16.
Immunity ; 49(5): 886-898.e5, 2018 11 20.
Article in English | MEDLINE | ID: mdl-30446383

ABSTRACT

Pathogenic Th17 (pTh17) cells drive inflammation and immune-pathology, but whether pTh17 cells are a Th17 cell subset whose generation is under specific molecular control remains unaddressed. We found that Ras p21 protein activator 3 (RASA3) was highly expressed by pTh17 cells relative to non-pTh17 cells and was required specifically for pTh17 generation in vitro and in vivo. Mice conditionally deficient for Rasa3 in T cells showed less pathology during experimental autoimmune encephalomyelitis. Rasa3-deficient T cells acquired a Th2 cell-biased program that dominantly trans-suppressed pTh17 cell generation via interleukin 4 production. The Th2 cell bias of Rasa3-deficient T cells was due to aberrantly elevated transcription factor IRF4 expression. RASA3 promoted proteasome-mediated IRF4 protein degradation by facilitating interaction of IRF4 with E3-ubiquitin ligase Cbl-b. Therefore, a RASA3-IRF4-Cbl-b pathway specifically directs pTh17 cell generation by balancing reciprocal Th17-Th2 cell programs. These findings indicate that a distinct molecular program directs pTh17 cell generation and reveals targets for treating pTh17 cell-related pathology and diseases.


Subject(s)
Cell Differentiation/genetics , GTPase-Activating Proteins/genetics , Th17 Cells/cytology , Th17 Cells/metabolism , Th2 Cells/cytology , Th2 Cells/metabolism , Animals , Autoimmunity , Biomarkers , Encephalomyelitis, Autoimmune, Experimental/etiology , Encephalomyelitis, Autoimmune, Experimental/metabolism , Encephalomyelitis, Autoimmune, Experimental/pathology , GTPase-Activating Proteins/metabolism , Gene Expression , Immunophenotyping , Interferon Regulatory Factors/genetics , Interferon Regulatory Factors/metabolism , Mice , Proteolysis , RNA, Messenger , Th17 Cells/immunology , Th2 Cells/immunology
17.
Nature ; 595(7868): 591-595, 2021 07.
Article in English | MEDLINE | ID: mdl-34163069

ABSTRACT

The development of cancer is intimately associated with genetic abnormalities that target proteins with intrinsically disordered regions (IDRs). In human haematological malignancies, recurrent chromosomal translocation of nucleoporin (NUP98 or NUP214) generates an aberrant chimera that invariably retains the nucleoporin IDR-tandemly dispersed repeats of phenylalanine and glycine residues1,2. However, how unstructured IDRs contribute to oncogenesis remains unclear. Here we show that IDRs contained within NUP98-HOXA9, a homeodomain-containing transcription factor chimera recurrently detected in leukaemias1,2, are essential for establishing liquid-liquid phase separation (LLPS) puncta of chimera and for inducing leukaemic transformation. Notably, LLPS of NUP98-HOXA9 not only promotes chromatin occupancy of chimera transcription factors, but also is required for the formation of a broad 'super-enhancer'-like binding pattern typically seen at leukaemogenic genes, which potentiates transcriptional activation. An artificial HOX chimera, created by replacing the phenylalanine and glycine repeats of NUP98 with an unrelated LLPS-forming IDR of the FUS protein3,4, had similar enhancing effects on the genome-wide binding and target gene activation of the chimera. Deeply sequenced Hi-C revealed that phase-separated NUP98-HOXA9 induces CTCF-independent chromatin loops that are enriched at proto-oncogenes. Together, this report describes a proof-of-principle example in which cancer acquires mutation to establish oncogenic transcription factor condensates via phase separation, which simultaneously enhances their genomic targeting and induces organization of aberrant three-dimensional chromatin structure during tumourous transformation. As LLPS-competent molecules are frequently implicated in diseases1,2,4-7, this mechanism can potentially be generalized to many malignant and pathological settings.


Subject(s)
Chromatin/genetics , Homeodomain Proteins/genetics , Intrinsically Disordered Proteins/genetics , Neoplasms/pathology , Nuclear Pore Complex Proteins/genetics , Translocation, Genetic , Animals , Carcinogenesis , Female , HEK293 Cells , HeLa Cells , Humans , Mice , Mice, Inbred BALB C , Neoplasms/genetics , Oncogene Proteins, Fusion/genetics , Transcription Factors/genetics , Transcriptional Activation
18.
Proc Natl Acad Sci U S A ; 121(4): e2320602121, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38227656

ABSTRACT

Foxp3+CD4+ regulatory T (Treg) cells found within tissues regulate local immunity, inflammation, and homeostasis. Tregs in epididymal visceral adipose tissue (eVAT) are critical regulators of local and systemic inflammation and metabolism. During aging and under obesogenic conditions, eVAT Tregs undergo transcriptional and phenotypic changes and are important for containing inflammation and normalizing metabolic indices. We have employed single-cell RNA sequencing, single-cell Tra and Trb sequencing, adoptive transfers, photoconvertible mice, cellular interaction analyses, and in vitro cultures to dissect the evolving heterogeneity of eVAT Tregs with aging and obesity. Distinct Treg subtypes with distinguishable gene expression profiles and functional roles were enriched at differing ages and with differing diets. Like those in lean mice, eVAT Tregs in obese mice were not primarily recruited from the circulation but instead underwent local expansion and had a distinct and diversified T cell receptor repertoire. The different eVAT-Treg subtypes were specialized in different functions; for example, the subtypes enriched in lean, but not obese, mice suppressed adipogenesis. The existence of functionally divergent eVAT-Treg subtypes in response to obesogenic conditions presents possibilities for precision therapeutics in the context of obesity.


Subject(s)
Adipose Tissue , T-Lymphocytes, Regulatory , Mice , Animals , Adipose Tissue/metabolism , Diet , Obesity/metabolism , Mice, Obese , Inflammation/metabolism
19.
Proc Natl Acad Sci U S A ; 121(16): e2317978121, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38593069

ABSTRACT

Mosquito-borne flaviviruses such as dengue (DENV) and Zika (ZIKV) cause hundreds of millions of infections annually. The single-stranded RNA genome of flaviviruses is translated into a polyprotein, which is cleaved equally into individual functional proteins. While structural proteins are packaged into progeny virions and released, most of the nonstructural proteins remain intracellular and could become cytotoxic if accumulated over time. However, the mechanism by which nonstructural proteins are maintained at the levels optimal for cellular fitness and viral replication remains unknown. Here, we identified that the ubiquitin E3 ligase HRD1 is essential for flaviviruses infections in both mammalian hosts and mosquitoes. HRD1 directly interacts with flavivirus NS4A and ubiquitylates a conserved lysine residue for ER-associated degradation. This mechanism avoids excessive accumulation of NS4A, which otherwise interrupts the expression of processed flavivirus proteins in the ER. Furthermore, a small-molecule inhibitor of HRD1 named LS-102 effectively interrupts DENV2 infection in both mice and Aedes aegypti mosquitoes, and significantly disturbs DENV transmission from the infected hosts to mosquitoes owing to reduced viremia. Taken together, this study demonstrates that flaviviruses have evolved a sophisticated mechanism to exploit the ubiquitination system to balance the homeostasis of viral proteins for their own advantage and provides a potential therapeutic target to interrupt flavivirus infection and transmission.


Subject(s)
Aedes , Flavivirus Infections , Flavivirus , Zika Virus Infection , Zika Virus , Animals , Mice , Flavivirus/genetics , Zika Virus/genetics , Ubiquitin/metabolism , Ligases/metabolism , Viral Proteins/metabolism , Mammals
20.
Mol Cell ; 72(2): 341-354.e6, 2018 10 18.
Article in English | MEDLINE | ID: mdl-30270106

ABSTRACT

Androgen receptor splice variant 7 (AR-V7) is crucial for prostate cancer progression and therapeutic resistance. We show that, independent of ligand, AR-V7 binds both androgen-responsive elements (AREs) and non-canonical sites distinct from full-length AR (AR-FL) targets. Consequently, AR-V7 not only recapitulates AR-FL's partial functions but also regulates an additional gene expression program uniquely via binding to gene promoters rather than ARE enhancers. AR-V7 binding and AR-V7-mediated activation at these unique targets do not require FOXA1 but rely on ZFX and BRD4. Knockdown of ZFX or select unique targets of AR-V7/ZFX, or BRD4 inhibition, suppresses growth of castration-resistant prostate cancer cells. We also define an AR-V7 direct target gene signature that correlates with AR-V7 expression in primary tumors, differentiates metastatic prostate cancer from normal, and predicts poor prognosis. Thus, AR-V7 has both ARE/FOXA1 canonical and ZFX-directed non-canonical regulatory functions in the evolution of anti-androgen therapeutic resistance, providing information to guide effective therapeutic strategies.


Subject(s)
Alternative Splicing/genetics , Carcinogenesis/genetics , Kruppel-Like Transcription Factors/genetics , Oncogenes/genetics , Prostatic Neoplasms, Castration-Resistant/genetics , Receptors, Androgen/genetics , Animals , Cell Differentiation/genetics , Cell Line , Cell Line, Tumor , Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Neoplastic/genetics , HEK293 Cells , Hepatocyte Nuclear Factor 3-alpha/genetics , Humans , Male , Mice , Mice, Inbred NOD , Mice, SCID , Nuclear Proteins/genetics , Promoter Regions, Genetic/genetics
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