Adenosine-to-inosine (A-to-I) RNA editing, which is catalyzed by a family of adenosine deaminase acting on RNA (ADAR) enzymes, is important in the epitranscriptomic regulation of RNA metabolism. However, the role of A-to-I RNA editing in vascular disease is unknown. Here we show that cathepsin S mRNA (CTSS), which encodes a cysteine protease associated with angiogenesis and atherosclerosis, is highly edited in human endothelial cells. The 3' untranslated region (3' UTR) of the CTSS transcript contains two inverted repeats, the AluJo and AluSx+ regions, which form a long stem–loop structure that is recognized by ADAR1 as a substrate for editing. RNA editing enables the recruitment of the stabilizing RNA-binding protein human antigen R (HuR; encoded by ELAVL1) to the 3' UTR of the CTSS transcript, thereby controlling CTSS mRNA stability and expression. In endothelial cells, ADAR1 overexpression or treatment of cells with hypoxia or with the inflammatory cytokines interferon-? and tumor-necrosis-factor-a induces CTSS RNA editing and consequently increases cathepsin S expression. ADAR1 levels and the extent of CTSS RNA editing are associated with changes in cathepsin S levels in patients with atherosclerotic vascular diseases, including subclinical atherosclerosis, coronary artery disease, aortic aneurysms and advanced carotid atherosclerotic disease. These results reveal a previously unrecognized role of RNA editing in gene expression in human atherosclerotic vascular diseases. Overall design: 1) Evaluation of transcriptome expression and RNA editing sites (A-to-G and T-to-C nucleotide mismatches) in poly(A) RNA-seq data derived from endothelial cell transcriptome after ADAR1 or ADAR2 knockdown (n=2 biological replicates per condition, total n=8 biological samples). 2) Evaluation of transcriptome expression and RNA editing sites (A-to-G and T-to-C nucleotide mismatches) in total-RNA-seq data derived from peripheral blood mononuclear cells (n=12 total biological samples; n=4 replicates per condition). 3) Evaluation of transcriptome expression and RNA editing sites (A-to-G and T-to-C nucleotide mismatches) in total-RNA-seq data derived from endothelial cell transcriptome under basal and hypoxic conditions (n=2 biological replicates per condition, total n=4 biological samples). 4) Evaluation of RNA editing sites (A-to-G and T-to-C nucleotide mismatches) in total RNA-seq data derived from endothelial cell transcriptome under basal and hypoxic conditions after ADAR1 knockdown (n=3 replicates per condition, total n=12 biological samples). 5) HuR iCLIP RNA-sequencing data derived from HUVEC HuR iCLIP after ADAR1 knockdown (scrambled control and siADAR1, n=1 per condition, total n=2 biological samples).
Adenosine-to-inosine RNA editing controls cathepsin S expression in atherosclerosis by enabling HuR-mediated post-transcriptional regulation.
No sample metadata fields
View SamplesThousands of long non-coding RNAs (lncRNAs) have been identified in the human genome, many of which are not conserved in lower mammals. The majority of these lncRNAs remain functionally uncharacterized and may have important implications in human physiology and disease. Here, we identify a primate-specific lncRNA, CHROME, which is increased in the plasma and atherosclerotic plaques of individuals with coronary artery disease compared to healthy controls. Using a loss-of-function approach, we show that CHROME functions as a competing endogenous RNA of microRNAs and regulates the concentration and biological functions of target genes. Overall design: We used three replicate samples of HEPG2 cells that were treated with shRNA for CHROME compated to three replicate control samples.
The long noncoding RNA CHROME regulates cholesterol homeostasis in primate.
Specimen part, Cell line, Subject
View SamplesWe individually examined the ability of human ARGFX, DPRX, LEUTX, and TPRX1 to regulate gene expression by ectopically expressing these proteins in fibroblasts. Overall design: Each gene along with an empty control vector were transfected individually to drive ectopic expression in human dermal fibroblasts, in triplicate.
Evolutionary origin and functional divergence of totipotent cell homeobox genes in eutherian mammals.
Specimen part, Subject
View SamplesWhile blood transcriptional profiling has improved diagnosis and understanding of disease pathogenesis of adult tuberculosis (TB), no studies applying gene expression profiling of children with TB have been described so far. In this study, we have compared whole blood gene expression in childhood TB patients, as well as in healthy latently infected (LTBI) and uninfected (HC) children in a cohort of Warao Amerindians in the Delta Amacuro in Venezuela. We identified a 116-gene signature set by means of random forest analysis that showed an average prediction error of 11% for TB vs. LTBI and for TB vs. LTBI vs. HC in our dataset. Furthermore, a minimal set of only 9 genes showed a significant predictive value for all previously published adult studies using whole blood gene expression, with average prediction errors between 17% and 23%. Additionally, a minimal gene set of 42 genes with a comparable predictive value to the 116-gene set in both our dataset and the previously published literature cohorts for the comparsion of TB vs. LTBI vs. HC was identified. In order to identify a robust representative gene set that would hold stand among different ethnic populations, we selected ten genes that were highly discriminative between TB, LTBI and HC in all literature datasets as well as in our dataset. Functional annotation of these ten genes highlights a possible role for genes involved in calcium signaling and calcium metabolism as biomarkers for active TB. These ten genes were validated by quantitative real-time polymerase chain reaction in an additional cohort of 54 Warao Amerindian children with LTBI, HC and non-TB pneumonia. Decision tree analysis indicated that five of the ten genes were sufficient to diagnose 78% of the TB cases correctly with 100% specificity. We conclude that our data justify the further exploration of our signature set as biomarkers to diagnose childhood TB. Furthermore, as the identification of different biomarkers in ethnically distinct cohorts is apparent, it is important to cross-validate newly identified markers in all available cohorts.
A predictive signature gene set for discriminating active from latent tuberculosis in Warao Amerindian children.
Sex, Age
View SamplesLRF, which is encoded by the ZBTB7A gene and formerly known as POKEMON (POK erythroid myeloid ontogenic factor), was originally identified as a PLZF (promyelocytic leukemia zinc finger) homologue interacting with BCL6 (B-cell lymphoma 6). LRF is a transcription factor that is broadly expressed in hematopoietic lineage cells, but its expression is particularly high in erythroblasts and germinal center (GC) B-cells. The goal of this study is to assess the effect of LRF loss on the LT-HSC transcriptome. Nine days after injection of adult mice with polyinosinic polycytidylic acid (pIpc) to activate Cre, total RNAs were isolated from double-sorted LT-HSCs from LRF Flox/+ Mx1-Cre+ and LRF Flox/Flox Mx1-Cre+ mice and processed for microarray analysis.
LRF-mediated Dll4 repression in erythroblasts is necessary for hematopoietic stem cell maintenance.
Age, Specimen part, Time
View SamplesB cells are indispensable for humoral immunity, as they ultimately give rise to antibody-secreting plasma cells. During T cell-dependent antibody responses, naive B cells form germinal centers (GCs), a distinct histologic structure found in secondary lymphoid organs. Naive B cells become activated upon interaction with T cells and antigen presenting cells, and begin to rapidly proliferate and form the characteristic GC structure.
The LRF transcription factor regulates mature B cell development and the germinal center response in mice.
Age, Specimen part
View SamplesWe previously showed that severe liver diseases are characterized by expansion of liver progenitor cells (LPC), which correlates with disease severity. However, the origin and role of LPC in liver physiology and in the hepatic response to injury remains a contentious topic. We have now used genetic lineage tracing of Hnf1-expressing biliary duct cells to assess their contribution to LPC expansion and hepatocyte generation during normal liver homeostasis, and following different types of liver injury. We found that ductular reaction cells in human cirrhotic livers express HNF1. However, HNF1 expression was not present in newly generated EpCAM-positive hepatocytes. Using a tamoxifen-inducible Hnf1CreER/R26RYFP/LacZ mouse, we show that there is no contribution of the biliary epithelium to hepatocyte turnover during liver homeostasis in healthy mice. Moreover, after loss of liver mass, Hnf1+ LPC did not contribute to hepatocyte regeneration. We also assessed the contribution of Hnf1+ cells following acute and repeated liver injury. All animal models showed expansion of LPC, as assessed by immunostaining and gene expression profile of sorted YFP-positive cells. A contribution of Hnf1+ LPC to hepatocyte generation was not detected in animal models of liver injury with preserved hepatocyte regenerative potential such as acute acetaminophen, carbon tetrachloride injury, or chronic diethoxycarbonyl-1,4-dihydro-collidin (DDC)-diet. However, in mice fed with choline-deficient ethionine-supplemented (CDE)-diet, which causes profound hepatocyte damage and arrest, a small number of hepatocytes were derived from Hnf1+ cells. Conclusion: Hnf1+ cells do not participate in hepatocyte turnover in the healthy liver or during liver regeneration after partial hepatectomy. After liver injury, LPC arise from the biliary duct epithelium, which gives rise to a limited number of hepatocytes only when hepatocyte regeneration is compromised.
The biliary epithelium gives rise to liver progenitor cells.
No sample metadata fields
View SamplesVariant FhlA133 (Q11H, L14V, Y177F, K245R, M288K, and I342F) had eight- fold higher hydrogen production than FhlA wild-type under 30 min of anaerobic incubation in modified-complex 20 mM formate at 37C. The mechanism by which the FhlA133 mutations increase hydrogen production is by increasing the transcription of all of the genes activated by the native FhlA (FHL complex).
Protein engineering of the transcriptional activator FhlA To enhance hydrogen production in Escherichia coli.
No sample metadata fields
View SamplesTocopherols (vitamin E) are lipid-soluble antioxidants produced by all plants and algae, and many cyanobacteria, yet their functions in these photosynthetic organisms are still not fully understood. We have previously reported that the vitamin E deficient 2 (vte2) mutant of Arabidopsis thaliana is sensitive to low temperature (LT) due to impaired transfer cell wall (TCW) development and photoassimilate export, associated with massive callose deposition in transfer cells of the phloem. To further understand the roles of tocopherols in LT induced TCW development we compared the global transcript profiles of vte2 and wild type leaves during LT treatment.
Role of callose synthases in transfer cell wall development in tocopherol deficient Arabidopsis mutants.
Specimen part
View SamplesCD74, a Type II membrane glycoprotein and MHC class II chaperone (Ii), is normally expressed by cells associated with the immune system. CD74 also forms heterodimers with CD44 to generate receptors to macrophage migration inhibitory factor (MIF), a proinflammatory cytokine. Following targeted Cre-mediated deletion of Ikk in IkkDeltaHep mice (a strain highly susceptible to chemically-induced hepatotoxicity and hepatocarcinogenesis), CD74 is abundantly expressed by hepatocytes throughout liver acini (as detected by specific Western blots and immunohistochemical stains); it is not observed in either control IkkF/F hepatocytes or embryonic fibroblasts from Ikk-/- mice. Constitutive CD74 expression in IkkDeltaHep hepatocytes is also accompanied by significantly augmented expression of CD44 and genes associated with antigen processing and host defense. These observations suggest that IkkDeltaHep hepatocytes might directly respond to MIF signaling, accounting partly for the enhanced susceptibility of IkkDeltaHep mice to hepatotoxins and hepatocarcinogens, and also might exhibit unusual immunological properties including antigen presentation.
Targeted deletion of hepatocyte Ikkbeta confers growth advantages.
Specimen part
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