Upstream Binding Factor (UBF) is a unique multi-HMGB-box protein first identified as a co-factor in RNA polymerase I (RPI/PolI) transcription. However, its poor DNA sequence selectivity and its ability to generate nucleosome-like nucleoprotein complexes suggest a more generalized role in chromatin structure. We previously showed that extensive depletion of UBF reduced the number of actively transcribed ribosomal RNA (rRNA) genes, but had little effect on rRNA synthesis rates or cell proliferation, leaving open the question of its requirement for RPI transcription. Using conditional gene deletion in mouse, we now show that UBF is indeed essential for transcription of the rRNA genes.
Conditional inactivation of Upstream Binding Factor reveals its epigenetic functions and the existence of a somatic nucleolar precursor body.
Specimen part, Time
View SamplesUBF is an essential RNA Polymerase I (Pol I)-transcription factor. Our research investigates extra roles for UBF in regulation of Pol II gene expression. Our gene expression data identifies genes that are differentially regulated following UBF knockdown by siRNA.
A novel role for the Pol I transcription factor UBTF in maintaining genome stability through the regulation of highly transcribed Pol II genes.
Specimen part, Cell line
View SamplesBromodomain-containing protein 4 (BRD4) is an important epigenetic reader which promotes gene transcription to modulate cell-specific functions and is under intensive investigation for its potential as an anti-tumor therapeutic target. However, the role of BRD4 in non-transformed cells remains unclear. Here we demonstrate that BRD4 is required for the expression of epithelial-specific genes and suppression of stem cell-like properties by binding to the distal regions of epithelial-related genes. Moreover, BRD4 occupancy correlates with enhancer activity and enhancer RNA (eRNA) transcription of epithelial differentiation-specific genes. Interestingly, we show that BRD4 perturbation regulates the expression of Grainy Head-like transcription factor, GRHL3, whose depletion partially mimics BRD4 inhibition and blocks differentiated phenotype. By binding to the distal regions of GRHL3, BRD4 promotes RNA polymerase-II occupancy and thus affects eRNA transcription. Altogether, these findings provide evidence that BRD4 promotes a differentiated epithelial phenotype in non-transformed mammary cells at least in part through the activation of GRHL3 expression. Overall design: mRNA expression profiles of MCF10A cells under negative control siRNA, BRD4 siRNA or JQ1 treatment, in duplicates.
BRD4 promotes p63 and GRHL3 expression downstream of FOXO in mammary epithelial cells.
No sample metadata fields
View SamplesLong non-coding RNAs (lncRNAs) contribute to (patho)physiological processes in the heart. Aging is the major risk factor for cardiovascular disease and cardiomyocyte apoptosis is an underlying cause for age-related cardiac dysfunction. RNA sequencing of cardiomyocytes from young and aged mouse hearts revealed several aging-regulated lncRNAs. An siRNA screen for caspase activity identified the aging-regulated lncRNA Sarrah (ENSMUST00000140003) as anti-apoptotic, which we confirmed in human cells (human SARRAH is annotated as OXCT1-AS1). Importantly, human engineered heart tissue showed impaired contractile force development upon SARRAH knockdown compared with controls. Computational prediction of RNA-DNA triple helix formation showed that SARRAH may directly bind the promoters of genes downregulated after SARRAH silencing, which mainly consist of cell survival genes. Indeed, nuclear magnetic resonance spectroscopy confirmed RNA-DNA triple helix formation and cardiomyocytes lacking the triple helix-forming domain of Sarrah showed an increase in apoptosis. One of the key direct SARRAH targets is NRF2, an anti-oxidant transcription factor. Restoration of NRF2 levels after SARRAH silencing partially rescues the reduction in cell viability. RNA affinity purification mass spectrometry analysis identified CRIP2 as main protein interaction partner. Furthermore, SARRAH associates with acetyltransferase p300 and acetylated histone H3K27. Finally, Sarrah was also profoundly downregulated after acute myocardial infarction (AMI) in mice. Adeno-associated virus-mediated overexpression of Sarrah in mice showed better recovery of cardiac contractile function after AMI compared to control mice, as measured by echocardiography and magnetic resonance imaging, consistent with a decrease in cardiomyocyte cell death and an increase in endothelial cell proliferation. In summary, we identified the anti-apoptotic evolutionary conserved lncRNA Sarrah, which is downregulated by aging, as a pivotal regulator of cardiomyocyte survival. Sarrah overexpression has beneficial effects on AMI recovery highlighting it as a potential therapeutic approach against heart failure.
Aging-regulated anti-apoptotic long non-coding RNA Sarrah augments recovery from acute myocardial infarction.
Specimen part
View SamplesBackground and aims: Hepatitis C virus (HCV) infection is a major cause of liver disease including steatosis, fibrosis and liver cancer. Viral cure cannot fully eliminate the risk of disease progression and hepatocellular carcinoma (HCC) in advanced liver disease. The mechanisms for establishment of infection, liver disease progression and hepatocarcinogenesis are only partially understood. To address these questions, we probed the functional proteogenomic architecture of HCV infection within a hepatocyte-model. Methods: Time-resolved HCV infection of hepatocyte-like cells was analyzed by RNA sequencing, proteomics, metabolomics, and leveraged by integrative genomic analyses. Using differential expression, gene set enrichment analyses, and protein-protein interaction mapping we identified pathways relevant for liver disease pathogenesis that we validated in livers of 216 cirrhotic patients with HCV. Results: We uncovered marked changes in the protein expression of gene sets involved in innate immunity, metabolism and hepatocarcinogenesis. In infected cells, HCV enhances glucose metabolism and creates a Warburg-like shift of the lactate flux. HCV infection impaired the formation of peroxisomes -organelles required for long-chain fatty acid oxidation- causing intracellular fatty acid accumulation, which is a hallmark of non-alcoholic fatty liver disease (NAFLD). Ex vivo studies confirmed perturbed peroxisomes and revealed an association of hepatic catalase expression with clinical outcomes and phenotypes in HCV-associated cirrhosis, NAFLD and HCC cohorts. Conclusion: Our integrative analyses uncover how HCV perturbs the hepatocyte cell circuits to drive chronic liver disease and hepatocarcinogenesis. This proteogenomic atlas of HCV infection provides a model for the discovery of novel drivers for viral- and non-viral induced liver disease. Overall design: mRNA profiles of either mock or HCV-infected Huh7.5.1dif cells, performed in triplicates and collected every day between days 0 and 10 post infection. HCV infection reached plateau at day 7 post infection (pi). After day 7 pi unspecific effects cannot be excluded.
Combined Analysis of Metabolomes, Proteomes, and Transcriptomes of Hepatitis C Virus-Infected Cells and Liver to Identify Pathways Associated With Disease Development.
Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Immunopathology of childhood celiac disease-Key role of intestinal epithelial cells.
Specimen part, Cell line, Treatment
View SamplesThe transcription factor OTX2 has been implicated as an oncogene in medulloblastoma, which is the most common malignant brain tumor in children. It is highly expressed in most medulloblastomas and amplified in a subset of them. The role of OTX2 in medulloblastoma and its downstream targets are unclear. Therefore, we generated D425 medulloblastoma cells in which we can silence endogenous OTX2 by inducible shRNA. Silencing of OTX2 strongly inhibited cell proliferation and resulted in a neuronal-like differentiation. Expression profiling of time courses after silencing showed a progressive change in gene expression for many cellular processes. Down regulated genes were highly enriched for cell cycle and visual perception genes, while up regulated genes were enriched for genes involved in development and differentiation. This shift in expression profiles is reminiscent to changes described to occur during normal cerebellum development. OTX2 is expressed in proliferating granular progenitor cells, but the expression diminishes when these cells exit the cell cycle and start differentiating. ChIP-on-chip analyses of OTX2 in D425 cells showed that cell cycle and perception genes were direct OTX2 targets, while regulation of most differentiation genes appears to be indirect. These analyses provide the first insight in the molecular network of OTX2, demonstrating that OTX2 is essential in medulloblastoma and directly drives proliferation by regulating the expression of cell cycle genes. Since many of these genes also correlate in expression with OTX2 in primary tumors, they might be potential targets for therapy in medulloblastoma patients.
OTX2 directly activates cell cycle genes and inhibits differentiation in medulloblastoma cells.
Cell line, Time
View SamplesComparison of laminin binding and laminin non-binding germ cells
Defining the spermatogonial stem cell.
No sample metadata fields
View SamplesRat germ cells
Defining the spermatogonial stem cell.
No sample metadata fields
View SamplesAnalysis of the influence of celiac disease-associated bacteria and gluten on intestinal epithelial cells
Immunopathology of childhood celiac disease-Key role of intestinal epithelial cells.
Cell line, Treatment
View Samples