This SuperSeries is composed of the SubSeries listed below.
Role of p53 serine 46 in p53 target gene regulation.
Specimen part, Cell line, Compound
View SamplesThe tumor suppressor p53 plays a crucial role in cellular growth control inducing a plethora of cellular response pathways. The molecular mechanisms that discriminate between the distinct p53-responses towards different stress treatments have remained largely elusive. Here, we have analyzed the p53-regulated pathways induced by two chemotherapeutical treatments, Actinomycin D inducing growth arrest and Etoposide resulting in apoptosis. We found that the genome-wide p53-binding patterns are almost identical upon both treatments notwithstanding transcriptional differences that we observed in genome-wide transcriptome analysis. To assess the role of post-translational modifications in target gene choice and activation we investigated the extent of phosphorylation of Serine 46 of p53 bound to DNA (p53-pS46), a modification that has been linked to apoptosis-pathways, and the extent of phosphorylation of Serine 15 (p53-pS15), a general p53-activation mark. Interestingly, the overall extent of S46 phosphorylation of p53 bound to DNA is considerably higher in cells directed towards apoptosis while the degree of phosphorylation at S15 of DNA bound p53 remains highly similar upon both treatments. Moreover, our data suggest that, following different chemotherapeutical treatments, the extent of chromatin-associated p53 phosphorylated at S46 but not at pS15 is higher on certain apoptosis related target genes, including the BAX and PUMA genes. These data provide evidence that cell fate decisions are not made primarily on the level of general p53 DNA-binding, but possibly through post-translational modifications of chromatin bound p53.
Role of p53 serine 46 in p53 target gene regulation.
Specimen part, Cell line
View SamplesWe are investigating the response of human lymphoblastoid cells to low-dose exposure of environmental metals
Comparative genomic analyses identify common molecular pathways modulated upon exposure to low doses of arsenic and cadmium.
Cell line, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Epigenetics and Preeclampsia: Defining Functional Epimutations in the Preeclamptic Placenta Related to the TGF-β Pathway.
Specimen part, Disease, Race
View SamplesPlacental Tissue Samples from 36 women (17 normotensive women, denoted with a P, and 19 preeclamptic women, denoted with a Q) were analyzed for differenital methylation
Epigenetics and Preeclampsia: Defining Functional Epimutations in the Preeclamptic Placenta Related to the TGF-β Pathway.
Specimen part, Disease, Race
View SamplesWe are investigating the mRNA expression profiles of human lung cells to gaseous urban mixtures
A toxicogenomic comparison of primary and photochemically altered air pollutant mixtures.
Cell line, Treatment
View SamplesBackground: Transcription control of mitochondrial metabolism is essential for cellular function. A better understanding of this process will aid the elucidation of mitochondrial disorders, in particular of the many genetically unsolved cases of oxidative phosphorylation (OXPHOS) deficiency. Yet, to date only few studies have investigated nuclear gene regulation in the context of OXPHOS deficiency. In this study, we combined RNA sequencing of human complex I-deficient patient cells across 32 conditions of perturbed mitochondrial metabolism, with a comprehensive analysis of gene expression patterns, co-expression calculations and transcription factor binding sites. Results: Our analysis shows that OXPHOS genes have a significantly higher co-expression with each other than with other genes, including mitochondrial genes. We found no evidence for complex-specific mRNA expression regulation in the tested cell types and conditions: subunits of different OXPHOS complexes are similarly (co-)expressed and regulated by a common set of transcription factors. However, we did observe significant differences between the expression of OXPHOS complex subunits compared to assembly factors, suggesting divergent transcription programs. Furthermore, complex I co-expression calculations identified 684 genes with a likely role in OXPHOS biogenesis and function. Analysis of evolutionarily conserved transcription factor binding sites in the promoters of these genes revealed almost all known OXPHOS regulators (including GABP, NRF1/2, SP1, YY1, E-box factors) and a set of six yet uncharacterized candidate transcription factors (ELK1, KLF7, SP4, EHF, ZNF143, and EL2). Conclusions: OXPHOS genes share an expression program distinct from other mitochondrial genes, indicative of targeted regulation of this mitochondrial sub-process. Within the subset of OXPHOS genes we established a difference in expression between subunits and assembly factors. Most transcription regulators of genes that co-express with complex I are well-established factors for OXPHOS biogenesis. For the remaining six factors we here suggest for the first time a link with transcription regulation in OXPHOS deficiency. Overall design: RNA-SEQ of whole cell RNA in 2 control and 2 complex I deficient patient fibroblast cell lines treated with 4 compounds in duplicate, resulting in a total of 2x2x4x2=32 samples
Transcriptome analysis of complex I-deficient patients reveals distinct expression programs for subunits and assembly factors of the oxidative phosphorylation system.
No sample metadata fields
View SamplesDefective complex I (CI) is the most common type of oxidative phosphorylation (OXPHOS) disease in patients, with an incidence of 1 in 5,000 live births. Complex I deficiency can present in infancy or early adulthood and shows a wide variety of clinical manifestations, including Leigh syndrome, (cardio)myopathy, hypotonia, stroke, ataxia and lactic acidosis. A number of critical processes and factors, like superoxide production, calcium homeostasis, mitochondrial membrane potential and mitochondrial morphology, are known to be involved in clinical CI deficiency, but not all factors are yet known and a complete picture is lacking.
Transcriptional changes in OXPHOS complex I deficiency are related to anti-oxidant pathways and could explain the disturbed calcium homeostasis.
Sex, Age, Specimen part, Disease, Disease stage
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Prenatal arsenic exposure and the epigenome: altered microRNAs associated with innate and adaptive immune signaling in newborn cord blood.
Specimen part
View SamplesThe Biomarkers of Exposure to ARsenic (BEAR) pregnancy cohort in Gmez Palacio, Mexico was recently established to better understand the impacts of prenatal exposure to inorganic arsenic (iAs). In this study, we examined a subset (n=40) of newborn cord blood samples for microRNA (miRNA) expression changes associated with in utero arsenic exposure. Levels of iAs in maternal drinking water (DW-iAs) and maternal urine were assessed. Levels of DW-iAs ranged from below detectable values to 236 g/L (mean=51.7 g/L). Total arsenic in maternal urine (U-tAs) was defined as the sum of iAs and its monomethylated and dimethylated metabolites (MMAs and DMAs, respectively) and ranged from 6.2 to 319.7 g/L (mean=64.5 g/L). Genome-wide miRNA expression analysis of cord blood revealed 12 miRNAs with increasing expression associated with U-tAs. Transcriptional targets of the miRNAs were computationally predicted and subsequently assessed using transcriptional profiling. Pathway analysis demonstrated that the U-tAs-associated miRNAs are involved in signaling pathways related to known health outcomes of iAs exposure including cancer and diabetes mellitus. Immune response-related mRNAs were also identified with decreased expression levels associated with U-tAs, and predicted to be mediated in part by the arsenic-responsive miRNAs. Results of this study highlight miRNAs as novel responders to prenatal arsenic exposure that may contribute to associated immune response perturbations.
Prenatal arsenic exposure and the epigenome: altered microRNAs associated with innate and adaptive immune signaling in newborn cord blood.
Specimen part
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