This SuperSeries is composed of the SubSeries listed below.
Mechanisms of epigenetic and cell-type specific regulation of Hey target genes in ES cells and cardiomyocytes.
Specimen part
View SamplesWe used an in vitro cardiomyocyte differentiation system with inducible Hey1 or Hey2 expression to study target gene regulation in cardiomyocytes (CM) generated from murine embryonic stem cells (ESC). The effects of Hey1 and Hey2 are largely redundant, but cell type specific. The number of regulated genes is comparable between ESC and CM, but the total number of binding sites is much higher, especially in ESC, targeting mainly genes involved in transcriptional regulation and developmental processes. Repression by Hey generally correlates with the extent of Hey-binding to target promoters, subsequent Hdac recruitment and lower histone acetylation. Functionally, treatment with the Hdac inhibitor TSA abolished Hey target gene regulation. However, in CM the repressive effect of Hey-binding is lost for a subset of genes. These lack Hey-dependent histone deacetylation in CM and are enriched for binding sites of cardiac specific activators like Srf, Nkx2-5, and Gata4.
Mechanisms of epigenetic and cell-type specific regulation of Hey target genes in ES cells and cardiomyocytes.
No sample metadata fields
View SamplesWe used an in vitro cardiomyocyte differentiation system with inducible Hey1 or Hey2 expression to study target gene regulation in cardiomyocytes (CM) generated from murine embryonic stem cells (ESC). The effects of Hey1 and Hey2 are largely redundant, but cell type specific. The number of regulated genes is comparable between ESC and CM, but the total number of binding sites is much higher, especially in ESC, targeting mainly genes involved in transcriptional regulation and developmental processes. Repression by Hey generally correlates with the extent of Hey-binding to target promoters, subsequent Hdac recruitment and lower histone acetylation. Functionally, treatment with the Hdac inhibitor TSA abolished Hey target gene regulation. However, in CM the repressive effect of Hey-binding is lost for a subset of genes. These lack Hey-dependent histone deacetylation in CM and are enriched for binding sites of cardiac specific activators like Srf, Nkx2-5, and Gata4. Overall design: ES cells and cardiomyocytes with Hey1 or Hey2 overexpression were compared to control cells
Mechanisms of epigenetic and cell-type specific regulation of Hey target genes in ES cells and cardiomyocytes.
No sample metadata fields
View SamplesGene copy number variation (CNV) is a form of genetic polymorphism that contributes significantly to genome size and function but remains poorly characterized due to technological limitations. Inter-specific comparisons of CNVs in recently diverged plant species are crucial to uncover selection patterns underlying adaptation of a species to stressful environments. Especially given that gene amplifications have long been implicated in emergence of species-specific traits, we conducted a genome-wide survey to identify species-specific gene copy number expansions and deletions in the model extremophile species - Arabidopsis halleri that has diverged in evolutionarily recent time from Arabidopsis thaliana.
Between-species differences in gene copy number are enriched among functions critical for adaptive evolution in Arabidopsis halleri.
Specimen part
View SamplesThe -amyloid precursor protein APP and the related APLPs, undergo complex proteolytic processing giving rise to several fragments. Whereas it is well established that A accumulation is a central trigger for Alzheimer disease (AD), the physiological role of APP family members and their diverse proteolytic products is still largely unknown. The secreted APPs ectodomain has been shown to be involved in neuroprotection and synaptic plasticity. The -secretase generated APP intracellular domain AICD, functions as a transciptional regulator in heterologous reporter assays, although its role for endogenous gene regulation has remained controversial. To gain further insight into the molecular changes associated with knockout phenotypes and to elucidate the physiological functions of APP family members including their proposed role as transcriptional regulators we performed a DNA microarray transcriptome profiling of the frontal cortex of adult wild type, APP-/-, APLP2-/- and APPs knockin (KI) mice, APP/, expressing solely the secreted APPs ectodomain. Biological pathways affected by the lack of APP family members included regulation of neurogenesis, regulation of transcription and regulation of neuron projection development. Comparative analysis of transcriptome changes and qPCR validation identified co-regulated gene sets. Interestingly, these included heat shock proteins and plasticity related genes that were down-regulated in knock-out cortices. In contrast, we failed to detect significant differences in expression of previously proposed AICD target genes including Bace1, Kai1, Gsk3b, p53, Tip60 and Vglut2. Only Egfr was slightly up-regulated in APLP2-/- mice. Comparison of APP-/- and APP/ with wild-type mice revealed a high proportion of co-regulated genes indicating an important role of the C-terminus for cellular signaling. Finally, comparison of APLP2-/- on different genetic backgrounds revealed that background related transcriptome changes may dominate over changes due to the knockout of a single gene. Shared transcriptome profiles corroborated closely related physiological functions of APP family members in the adult central nervous system. As expression of proposed AICD target genes was not altered in adult cortex, this may indicate that these genes are not affected by lack of APP under resting conditions or only in a small subset of cells.
Comparative transcriptome profiling of amyloid precursor protein family members in the adult cortex.
Sex, Specimen part
View SamplesIn this study we have performed expression analysis using paired FF-FFPE glioma samples. We show that expression data from FFPE glioma material is concordant with expression data from matched FF tissue, and can be used for molecular profiling in gliomas.
Gene expression profiles of gliomas in formalin-fixed paraffin-embedded material.
Specimen part, Disease stage
View SamplesPostmenopausal hormone therapy (HT) is associated with many diseases and conditions, but the underlying molecular mechanisms involved are incompletely understood. The aim of the current study was to investigate the effect of 4 types of HT on gene transcription. 24 women (6 women in 4 treatment groups) received 2 mg 17-estradiol combined with 1 mg noresthisterone acetate (NETA), 1 mg 17-estradiol combined with 0.5 mg NETA, tibolone, or raloxifene hydrochloride. RNA was isolated from whole blood before treatment (baseline) and after 6 weeks on treatment. The changes in mRNA from baseline to 6 weeks were assessed with a microarray chip.
A microarray study on the effect of four hormone therapy regimens on gene transcription in whole blood from healthy postmenopausal women.
Sex, Specimen part
View SamplesThe MYC transcription factor is an unstable protein and its turnover is controlled by the ubiquitin system. Ubiquitination enhances MYC-dependent transactivation, but the underlying mechanism remains unresolved. Here we show that proteasomal turnover of MYC is dispensable for recruitment of RNA polymerase II (RNAPII), but is required to promote transcriptional elongation at MYC target genes. Degradation of MYC stimulates histone acetylation and recruitment of BRD4 and P-TEFb to target promoters, leading to phosphorylation of RNAPII CTD and the release of elongating RNAPII. In the absence of degradation, the RNA polymerase II-associated factor (PAF) complex associates with MYC via interaction of its CDC73 subunit with a conserved domain in the amino-terminus of MYC ("MYC box I"), suggesting that a MYC/PAF complex is an intermediate in transcriptional activation. Since histone acetylation depends on a second highly conserved domain in MYCs amino-terminus ("MYC box II"), we propose that both domains co-operate to transfer elongation factors onto paused RNAPII. Overall design: RNA-Seq Experiments were performed in a primary breast epithelial cell line (IMEC).The cell line expressed doxycycline-inducible versions of MYC (WT;Kless,Swap=WTN-KC). Where indicated cells were transfected with siRNAs (siCtrl;siSKP2). Where indicated cells were treaed with the proteasome inhibitor MG132 or EtOH as solvent control. DGE was performed by comparing Dox-treated populations expressing either Dox-inducible MYC or a vector control or comparing Dox-induced cells with EtOH (solvent control) treated cells.
Ubiquitin-Dependent Turnover of MYC Antagonizes MYC/PAF1C Complex Accumulation to Drive Transcriptional Elongation.
No sample metadata fields
View SamplesExpression analyses comparing c-Fos expressing keratinocytes vs non-expressing controls.
Inflammation-mediated skin tumorigenesis induced by epidermal c-Fos.
Specimen part, Treatment, Time
View SamplesFbw7, the substrate recognition subunit of SCF(Fbw7) ubiquitin ligase, mediates turnover of multiple proto-oncoproteins and promotes its own degradation. Fbw7-mediated substrate degradation is antagonized by the Usp28 deubiquitinase. We now show, using knockout mice, that Usp28 preferentially deubiquitinates and stabilizes Fbw7. Monoallelic deletion of Usp28 maintains stable Fbw7 but destabilizes Fbw7 substrates. In contrast, complete knockout of Usp28 promotes Pin1-dependent autocatalytic turnover of Fbw7, accumulation of Fbw7 substrates and oncogenic transformation. Overexpression of Usp28 stabilizes both Fbw7 and its substrates and similarly enhances transformation. We propose that dual regulation of Fbw7 activity by Usp28 maintains physiological levels of Fbw7 substrates, and that both loss and overexpression of Usp28 in human cancer promote Fbw7 substrate accumulation. Overall design: RNAseq experiments of E13.5 murine embryonic fibroblasts (MEFs) derived from animals in which Usp28 was either deleted (-/-), wildtype (+/+) or heterozygous (+/-). In a first set of experiments immortalized MEFs of all three genotypes were analysed in biological triplicates. In a second set of experiments immortalized and Ras transformed MEFs of all three genotypes and MEFs which overexpress USP28 (+/+/+) where sequenced in duplicates.
Dual regulation of Fbw7 function and oncogenic transformation by Usp28.
No sample metadata fields
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