NAD(P)H:quinone Oxidoreductase (NQO1) is essential for cell defense against reactive oxidative species, cancer, and metabolic stress. Recently, NQO1 was found in ribonucleoprotein (RNP) complexes, but NQO1-interacting mRNAs and the functional impact of such interactions are not known. Here, we used ribonucleoprotein immunoprecipitation (RIP) and microarray analysis to identify comprehensively the subset of NQO1 target mRNAs in human hepatoma HepG2 cells. One of its main targets, SERPINA1 mRNA, encodes the serine protease inhibitor -1-antitrypsin, A1AT, which is associated with disorders including obesity-related metabolic inflammation, chronic obstructive pulmonary disease (COPD), liver cirrhosis and hepatocellular carcinoma. Biotin pulldown analysis indicated that NQO1 can bind the 3 untranslated region (UTR) and the coding region (CR) of SERPINA1 mRNA. NQO1 did not affect SERPINA1 mRNA levels; instead, it enhanced the translation of SERPINA1 mRNA, as NQO1 silencing decreased the size of polysomes forming on SERPINA1 mRNA and lowered the abundance of A1AT. Luciferase reporter analysis further indicated that NQO1 regulates SERPINA1 mRNA translation through the SERPINA1 3UTR. Accordingly, NQO1-KO mice had reduced hepatic and serum levels of A1AT and increased activity of neutrophil elastase, one of the main targets of A1AT. We propose that this novel mechanism of action of NQO1 as RNA-binding protein may help to explain its pleiotropic biological effects.
Novel RNA-binding activity of NQO1 promotes SERPINA1 mRNA translation.
Specimen part, Cell line, Treatment
View Samplesgene expression database and algorithm to define cell expression modules
Identifying gene expression modules that define human cell fates.
Specimen part
View SamplesThe mechanism of CD4(+) T cell depletion during chronic human immunodeficiency virus type 1 (HIV-1) infection remains unknown. Many studies suggest a significant role for chronic CD4(+) T cell activation. We assumed that the pathogenic process of excessive CD4(+) T cell activation would be reflected in the transcriptional profiles of activated CD4(+) T cells. Here we demonstrate that the transcriptional programs of in vivo activated CD4(+) T cells from untreated HIV(+) individuals are clearly different from those activated CD4(+) T cells from HIV(-) individuals. We observed a dramatic up-regulation of cell cycle-associated and interferon-stimulated transcripts in activated CD4(+) T cells of untreated HIV(+) individuals. Furthermore, we find an enrichment of proliferative and Type I interferon-responsive transcription factor binding sites in the promoters of genes that are differentially expressed in activated CD4(+) T cells of untreated HIV(+) individuals compared to HIV(-) individuals. We confirm these findings by examination of in vivo activated CD4(+) T cells. Taken together, these results suggest that activated CD4(+) T cells from untreated HIV(+) individuals are in a hyper-proliferative state that is modulated by Type I interferons. From these results, we propose a new model for CD4(+) T cell depletion during chronic HIV-1 infection.
Chronic CD4+ T-cell activation and depletion in human immunodeficiency virus type 1 infection: type I interferon-mediated disruption of T-cell dynamics.
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View SamplesAlternative promoters (APs) occur in >30% protein-coding genes and contribute to proteome diversity. However, large-scale analyses of AP regulation are lacking, and little is known about their potential physiopathologic significance. To better understand the transcriptomic impact of estrogens, which play a major role in breast cancer, we analyzed gene and AP regulation by estradiol in MCF7 cells using pan-genomic exon arrays. We thereby identified novel estrogen-regulated genes, and determined the regulation of AP-encoded transcripts in 150 regulated genes. In <30% cases, APs were regulated in a similar manner by estradiol, while in >70% cases, they were regulated differentially. The patterns of AP regulation correlated with the patterns of estrogen receptor (ER) and CCCTC-binding factor (CTCF) binding sites at regulated gene loci. Interestingly, among genes with differentially regulated APs, we identified cases where estradiol regulated APs in an opposite manner, sometimes without affecting global gene expression levels. This promoter switch was mediated by the DDX5/DDX17 family of ER coregulators. Finally, genes with differentially regulated promoters were preferentially involved in specific processes (e.g., cell structure and motility, and cell cycle). We show in particular that isoforms encoded by the NET1 gene APs, which are inversely regulated by estradiol, play distinct roles in cell adhesion and cell cycle regulation, and that their expression is differentially associated with prognosis in ER+ breast cancer. Altogether, this study identifies the patterns of AP regulation in estrogen-regulated genes, demonstrates the contribution of AP-encoded isoforms to the estradiol-regulated transcriptome, as well as their physiopathologic significance in breast cancer.
Estrogen regulation and physiopathologic significance of alternative promoters in breast cancer.
Disease, Disease stage, Cell line, Time
View SamplesWe examined if pediatric AMLs rank-ordered according to C/EBP expression showed the activation of similar pathways. AML samples were dichotomized into groups including the upper quartile (Q1) and the lower three quartiles (Q2-4) according to their C/EBP expression values. Moreover, AML samples were associated to French-American-British (FAB) classification.
CREB engages C/EBPδ to initiate leukemogenesis.
Specimen part, Disease
View SamplesIn support of our manuscript investigating the roles of ILCs and T cells in the maintenance of gut hoemostasis, we have performed RNAseq on terminal illeum of mice lacking either all adaptive immune cells (RAG1 -/-), deficient in T cells (TCRalpha -/-), or deficient in T cells but co-housed with wild-type mice and RAG1 -/- mice. Overall design: Tissues from three mice per group were analysed, and the following comparisions were made: RAG1-/- vs. WT C57BL/6 and TCRa-/- co-housed vs TCRa-/- seperately housed. Differential expression genes were identified at 1% FDR using DESeq2.
Innate and adaptive lymphocytes sequentially shape the gut microbiota and lipid metabolism.
Subject
View SamplesTo examine the role of CREB overexpression in hematopoiesis, we created a model of leukemia in zebrafish by overexpressing the human CREB in the myeloid hematopoietic lineage. Whole transcriptome analysis of kidney-marrow revealed 171 genes differently expressed between CREB- and control-zebrafish (five per group). Interestingly, the integration of this signature with human deposited data revealed that this tumor resembled a human AML at transcriptome level.
CREB engages C/EBPδ to initiate leukemogenesis.
Specimen part
View SamplesComparison of the meis2b+ and the meis2b- halves of the atrium of the adult zebrafish atrium reveals the existence of two different transcriptional domains. These two domains analogous to that of the two atria in terrestrial vertebrates Overall design: To determine the expression profiles of the Tg(meis2b-reporter)-positive vs -negative atrial compartments, a total of 6 hearts of 3 mpf Tg(meis2b-reporter) zebrafish were micro-dissected. A total of 4 pools were made: the first two pools, each contained 3 Tg(meis2b-reporter)-positive atrial compartments, and the other two contained the Tg(meis2b-reporter)-negative halves.
Distinct myocardial lineages break atrial symmetry during cardiogenesis in zebrafish.
Age, Specimen part, Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A systems analysis identifies a feedforward inflammatory circuit leading to lethal influenza infection.
Sex, Specimen part
View SamplesTranscriptomic comparison of 5 cell types during lethal and non-lethal influenza infection and further use of these signatures in a top-down systems analysis investigating the relative pathogenic contributions of direct viral damage to lung epithelium vs. dysregulated immunity during lethal influenza infection.
A systems analysis identifies a feedforward inflammatory circuit leading to lethal influenza infection.
Sex, Specimen part
View Samples