Fibrotic diseases have significant health impact and have been associated with differentiation of the resident fibroblasts into myofibroblasts. In particular, stiffened extracellular matrix and TGF-1 in fibrotic lesions have been shown to promote pathogenic myofibroblast activation and progression of fibrosis in various tissues. To better understand the roles of mechanical and chemical cues on myofibroblast differentiation and how they may crosstalk, we cultured primary valvular interstitial cells (VICs) isolated from porcine aortic valves and studied how traditional TCPS culture, which presents a non-physiologically stiff environment, and TGF-1 affect native VIC phenotypes.
Hydrogels preserve native phenotypes of valvular fibroblasts through an elasticity-regulated PI3K/AKT pathway.
Specimen part, Treatment
View SamplesHow animals coordinate gene expression in response to starvation is an outstanding problem closely linked to aging, obesity, and cancer. Newly hatched Caenorhabditis elegans respond to food deprivation by halting development and promoting long-term survival (L1 diapause), thereby providing an excellent model to study starvation response. Through a genetic search, we have discovered that the tumor suppressor Rb critically promotes survival during L1 diapause and likely does so by regulating the expression of genes in both insulin-IGF-1 signaling (IIS)-dependent and -independent pathways mainly in neurons and the intestine. Global gene expression analyses suggested that Rb maintains the starvation-induced transcriptome and represses the re-feeding induced transcriptome, including the repression of many pathogen/toxin/oxidative stress-inducible and metabolic genes, as well as the activation of many other stress-resistant genes, mitochondrial respiratory chain genes, and potential IIS receptor antagonists. Notably, the majority of genes dysregulated in starved L1 Rb(-) animals were not found to be dysregulated in fed conditions. Together, these findings identify Rb as a critical regulator of the starvation response and suggest a link between functions of tumor suppressors and starvation survival. These results may provide mechanistic insights into why cancer cells are often hypersensitive to starvation treatment.
The tumor suppressor Rb critically regulates starvation-induced stress response in C. elegans.
No sample metadata fields
View SamplesOur understanding of cellular mechanisms by which animals regulate their response to starvation is limited despite the close relevance of the problem to major human health issues. L1 diapause of Caenorhabditis elegans, where newly hatched first stage larval arrested in response to food-less environment, is an excellent system to study the problem. We found through genetic manipulation and lipid analysis that ceramide biosynthesis, particularly those with longer fatty acid side chains, critically impacts animal survival during L1 diapause. Genetic and expression analyses indicate that ceramide likely regulate this response by affecting gene expression and activity in multiple regulatory pathways known to regulate starvation-induced stress, including the insulin-IGF-1 signaling (IIS) pathway, Rb and other pathways that mediate pathogen/toxin/oxidative stress responses. These findings provide an important insight into the roles of sphingolipid metabolism in not only starvation response but also aging and food-response related human health problems.
Starvation-Induced Stress Response Is Critically Impacted by Ceramide Levels in Caenorhabditis elegans.
No sample metadata fields
View SamplesGene expresssion is not globally shut down in elo-5 as compared to N2
No associated publication
Specimen part
View SamplesExpression data from valvular interstitial cells cultured in 2D or 3D PEG hydrogel systems compared to culture on tissue culture polystyrene and freshly isolated cells
Transcriptional profiles of valvular interstitial cells cultured on tissue culture polystyrene, on 2D hydrogels, or within 3D hydrogels.
Specimen part
View SamplesThe Mediator complex allows communication between transcription factors and RNA polymerase II (RNAPII). CDK8, the kinase found in some variants of Mediator, has been characterized mostly as a transcriptional repressor. Recently, CDK8 was demonstrated to be a potent oncoprotein. Here we show that CDK8 is predominantly a positive regulator of gene expression within the serum response network, as it is required for expression of several members of the AP-1 and EGR family of oncogenic transcription factors (e.g. FOS, JUN, EGR1-3). Mechanistic studies demonstrate that CDK8 is not required for recruitment of RNAPII and promoter escape at these loci. Instead, CDK8 depletion leads to the appearance of slower elongation complexes carrying hypophosphorylated RNAPII. We show that CDK8-Mediator regulates precise steps in the assembly of a functional elongation complex, including the recruitment of P-TEFb and BRD4, but is dispensable for recruitment of SPT5 and FACT. Furthermore, CDK8-Mediator specifically interacts with P-TEFb. Thus, we uncovered a novel role for CDK8 in transcriptional regulation that may contribute to its oncogenic effects.
CDK8 is a positive regulator of transcriptional elongation within the serum response network.
Cell line
View SamplesComparative analysis of mouse cardiac left ventricle gene expression: voluntary wheel exercise and pregnancy-induced cardiac hypertrophy
Distinct cardiac transcriptional profiles defining pregnancy and exercise.
Sex, Specimen part
View SamplesGenome-wide expression analysis comparison with and without ionizing radiation in p53 mutant and wild type Drosophila larvae
Genome-wide expression analysis identifies a modulator of ionizing radiation-induced p53-independent apoptosis in Drosophila melanogaster.
Sex, Specimen part, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Anti-inflammatory properties of alpha- and gamma-tocopherol.
Sex
View SamplesThe perception that soy food products and dietary supplements will have beneficial effects on heart health has led to a massive consumer market. However, we have previously noted that diet has a profound effect on disease progression in a genetic model of hypertrophic cardiomyopathy (HCM). In this model, a soy-based diet negatively impacts cardiac function in male mice.
Remodeling the cardiac transcriptional landscape with diet.
Sex, Specimen part
View Samples