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[This corrects the article DOI: 10.3389/fcell.2021.670654.].
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The role of host genetic factors in COVID-19 outcomes remains unclear despite various genome-wide association studies (GWAS). We annotate all significant variants and those variants in high LD (R2 > 0.8) from the COVID-19 host genetics initiative (HGI) and identify risk genes by recognizing genes intolerant nonsynonymous mutations in coding regions and genes associated with cis-expression quantitative trait loci (cis-eQTL) in non-coding regions. These genes are enriched in the immune response pathway and viral life cycle. It has been found that host RNA binding proteins (RBPs) participate in different phases of the SARS-CoV-2 life cycle. We collect 503 RBPs that interact with SARS-CoV-2 RNA concluded from in vitro studies. Combining risk genes from the HGI with RBPs, we identify two COVID-19 risk loci that regulate the expression levels of FUBP1 and RAB2A in the lung. Due to the risk allele, COVID-19 patients show downregulation of FUBP1 and upregulation of RAB2A. Using single-cell RNA sequencing data, we show that FUBP1 and RAB2A are expressed in SARS-CoV-2-infected upper respiratory tract epithelial cells. We further identify NC_000001.11:g.77984833C>A and NC_000008.11:g.60559280T>C as functional variants by surveying allele-specific transcription factor sites and cis-regulatory elements and performing motif analysis. To sum up, our research, which associates human genetics with expression levels of RBPs, identifies FUBP1 and RAB2A as two risk genes for COVID-19 and reveals the anti-viral role of FUBP1 and the pro-viral role of RAB2A in the infection of SARS-CoV-2.
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COVID-19 , Proteínas de Ligação a DNA , Proteínas de Ligação a RNA , Proteínas rab de Ligação ao GTP , Humanos , COVID-19/genética , Proteínas de Ligação a DNA/genética , Estudo de Associação Genômica Ampla , RNA Viral , Proteínas de Ligação a RNA/genética , SARS-CoV-2 , Proteínas rab de Ligação ao GTP/genéticaRESUMO
Fate determination and expansion of Hematopoietic Stem and Progenitor Cells (HSPCs) is tightly regulated on both transcriptional and post-transcriptional level. Although transcriptional regulation of HSPCs have achieved a lot of advances, its post-transcriptional regulation remains largely underexplored. The small size and high fecundity of zebrafish makes it extraordinarily suitable to explore novel genes playing key roles in definitive hematopoiesis by large-scale forward genetics screening. Here, we reported a novel zebrafish mutant line gemin5 cas008 with a point mutation in gemin5 gene obtained by ENU mutagenesis and genetic screening, causing an earlier stop codon next to the fifth WD repeat. Gemin5 is an RNA-binding protein with multifunction in post-transcriptional regulation, such as regulating the biogenesis of snRNPs, alternative splicing, stress response, and translation control. The mutants displayed specific deficiency in definitive hematopoiesis without obvious defects during primitive hematopoiesis. Further analysis showed the impaired definitive hematopoiesis was due to defective proliferation of HSPCs. Overall, our results indicate that Gemin5 performs an essential role in regulating HSPCs proliferation.
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Besides their original regulating roles in the brain, spinal cord, retina, and peripheral nervous system for mediating fast excitatory synaptic transmission, glutamate receptors consisting of metabotropic glutamate receptors (GluRs) and ionotropic glutamate receptors (iGluRs) have emerged to have a critical role in the biology of cancer initiation, progression, and metastasis. However, the precise mechanism underpinning the signal transduction mediated by ligand-bound GluRs is not clearly elucidated. Here, we show that iGluRs, GluR1 and GluR2, are acetylated by acetyltransferase CREB-binding protein upon glutamate stimulation of cells, and are targeted by lysyl oxidase-like 2 for deacetylation. Acetylated GluR1/2 recruit ß-arrestin1/2 and signal transducer and activator of transcription 3 (STAT3) to form a protein complex. Both ß-arrestin1/2 and STAT3 are subsequently acetylated and activated. Simultaneously, activated STAT3 acetylated at lysine 685 translocates to mitochondria to upregulate energy metabolism-related gene transcription. Our results reveal that acetylation-dependent formation of GluR1/2-ß-arrestin1/2-STAT3 signalosome is critical for glutamate-induced cell proliferation.
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Large membrane proteins such as G protein-coupled receptors (GPCRs) are difficult for NMR study due to severe signal overlaps and unfavorable relaxation properties. We used a trimethylsilyl (TMS) group as a reporter group for 1 H NMR study of conformational changes in proteins, utilizing high-intensity 1 H NMR signals near 0 p.p.m. The ß2 -adrenergic receptor was labeled with TMS groups at two cysteines located at the cytoplasmic ends of helices VI and VII. Binding of various ligands led to changes in 1 H NMR signals, which manifested that helix VI is sensitive to G protein-specific activation, whereas helix VII is sensitive to ß-arrestin-specific activation. Thus, the TMS group is a useful reporter group in NMR for studying conformational changes in membrane proteins such as GPCRs.
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Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Receptores Adrenérgicos beta 2/metabolismo , Humanos , Ligantes , Conformação Proteica , Receptores Adrenérgicos beta 2/química , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Compostos de Trimetilsilil/químicaRESUMO
The response of endothelial cells to signaling stimulation is critical for vascular morphogenesis, homeostasis and function. Vascular endothelial growth factor-a (VEGFA) has been commonly recognized as a pro-angiogenic factor in vertebrate developmental, physiological and pathological conditions for decades. Here we report a novel finding that genetic ablation of CDP-diacylglycerol synthetase-2 (CDS2), a metabolic enzyme that controls phosphoinositide recycling, switches the output of VEGFA signaling from promoting angiogenesis to unexpectedly inducing vessel regression. Live imaging analysis uncovered the presence of reverse migration of the angiogenic endothelium in cds2 mutant zebrafish upon VEGFA stimulation, and endothelium regression also occurred in postnatal retina and implanted tumor models in mice. In tumor models, CDS2 deficiency enhanced the level of tumor-secreted VEGFA, which in-turn trapped tumors into a VEGFA-induced vessel regression situation, leading to suppression of tumor growth. Mechanistically, VEGFA stimulation reduced phosphatidylinositol (4,5)-bisphosphate (PIP2) availability in the absence of CDS2-controlled-phosphoinositide metabolism, subsequently causing phosphatidylinositol (3,4,5)-triphosphate (PIP3) deficiency and FOXO1 activation to trigger regression of CDS2-null endothelium. Thus, our data indicate that the effect of VEGFA on vasculature is context-dependent and can be converted from angiogenesis to vascular regression.
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Diacilglicerol Colinofosfotransferase/fisiologia , Neoplasias/irrigação sanguínea , Neovascularização Patológica/genética , Neovascularização Fisiológica/genética , Nucleotidiltransferases/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Animais , Linhagem Celular Tumoral , Diacilglicerol Colinofosfotransferase/genética , Células Endoteliais/enzimologia , Humanos , Melanoma Experimental , Camundongos , Camundongos Knockout , Nucleotidiltransferases/genética , Fator A de Crescimento do Endotélio Vascular/genética , Peixe-Zebra , Proteínas de Peixe-Zebra/genéticaRESUMO
Posttranslational modifications of mammalian c-Src N-terminal and C-terminal domains regulate distinct functions. Myristoylation of G2 controls its cell membrane association and phosphorylation of Y419/Y527 controls its activation or inactivation, respectively. We provide evidence that Src-cell membrane association-dissociation and catalytic activation-inactivation are both regulated by acetylation. In EGF-treated cells, CREB binding protein (CBP) acetylates an N-terminal lysine cluster (K5, K7, and K9) of c-Src to promote dissociation from the cell membrane. CBP also acetylates the C-terminal K401, K423, and K427 of c-Src to activate intrinsic kinase activity for STAT3 recruitment and activation. N-terminal domain phosphorylation (Y14, Y45, and Y68) of STAT3 by c-Src activates transcriptionally active dimers of STAT3. Moreover, acetyl-Src translocates into nuclei, where it forms the Src-STAT3 enhanceosome for gene regulation and cancer cell proliferation. Thus, c-Src acetylation in the N-terminal and C-terminal domains play distinct roles in Src activity and regulation.Significance: CBP-mediated acetylation of lysine clusters in both the N-terminal and C-terminal regions of c-Src provides additional levels of control over STAT3 transcriptional activity. Cancer Res; 78(11); 2825-38. ©2018 AACR.
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Carcinogênese/genética , Genes src/genética , Processamento de Proteína Pós-Traducional/genética , Fator de Transcrição STAT3/genética , Acetilação , Animais , Proteína de Ligação a CREB/genética , Proteína Tirosina Quinase CSK , Linhagem Celular , Linhagem Celular Tumoral , Núcleo Celular/genética , Proliferação de Células/genética , Proteínas de Ligação a DNA/genética , Células HEK293 , Humanos , Células MCF-7 , Camundongos , Células NIH 3T3 , Proteínas Nucleares/genética , Fosforilação/genética , Proteínas Tirosina Quinases/genética , Transativadores/genética , Transcrição Gênica/genética , Quinases da Família src/genéticaRESUMO
OBJECTIVE: The survey will reveal current status of subclinical vitamin A deficiency (SVAD) and explore its affecting factors in children of China. METHODS: Totally 8 669 children aged under 6 years were randomly selected from 14 provinces for clinical examination, health and dietary questionnaire and serum level of vitamin A measurement with fluorescence method. The cut-off value for SVAD was defined as = 0.70 micro mol/L. RESULTS: Prevalence of SVAD was 11.7% and that of suspected SVAD 39.2% in all subjects, which decreased with the increase of gross domestic product, average annual family income, mother's schooling and children's age. Prevalence of SVAD and suspected SVAD higher in rural areas (15.0%) than in urban areas (5.2%), and higher in children with a minority mother (22.6%) than in those with a Han nationality mother (8.7%). Prevalence of SVAD and suspected SVAD was higher in children whose blood samples were collected within one week in-taking vitamin A-rich food (12.6%-22.6%) than those in-taking vitamin A daily (4.1%-10.0%), and higher in children suffering from respiratory infection, fever and diarrhea two weeks before their blood collection (15.2%-20.3%) than in those without those diseases (10.1%-11.1%). Logistic regression analysis showed that poor family economic status, living in rural areas, children with a minority mother, younger age, no-dairy milk products intake, and respiratory infection and fever all were risk factors for SVAD. CONCLUSIONS: More than half of children under six years old in China (50.9%) had vitamin A nutrition problem. Varied factors played roles to different extent in SVAD in children.