Infections of the udder by Escherichia coli very often elicit acute inflammation, while Staphylococcus aureus infections tend to cause mild, subclinical inflammation and persistent infections. The molecular causes undercovering the different disease patterns are poorly understood. We therefore profiled kinetics and extent of global changes in the transcriptome of primary bovine mammary epithelia cells (MEC) subsequent to challenging them with heat inactivated preparations of E. coli or S. aureus pathogens. E. coli swiftly and strongly induced expression of cytokines and bactericidal factors. S. aureus elicited a retarded response and failed to quickly induce expression of bactericidal factors. Both pathogens induced a similar pattern of chemokines for cell recruitment into the udder, but E. coli stimulated their synthesis much faster and stronger. The genes which are exclusively and most strongly up-regulated by E. coli may be clustered into a regulatory network with Tumor necrosis factor alpha (TNF-a) and Interleukin 1 (IL-1) in a central position. In contrast, the expression of these master cytokines is barely regulated by S. aureus. Both pathogens quickly trigger enhanced expression of IL-6. This is still possible after completely abrogating MyD88 dependent TLR-signalling in MEC. The E. coli specific strong induction of TNF-a and IL-1 expression may be causative for the severe inflammatory symptoms of animals suffering from E. coli mastitis while avoidance to quickly induce synthesis of bactericidal factors may support persistent survival of S. aureus within the udder. We suggest that S. aureus subverts MyD88-dependent activation of immune gene expression in MEC.
Comparative kinetics of Escherichia coli- and Staphylococcus aureus-specific activation of key immune pathways in mammary epithelial cells demonstrates that S. aureus elicits a delayed response dominated by interleukin-6 (IL-6) but not by IL-1A or tumor necrosis factor alpha.
Specimen part, Treatment, Time
View SamplesThe tryptophan degrading enzyme TDO2 is downregulated upon HIF1alpha stabilization by exposure to both hypoxia as well as chemical hypoxia mimetics such as DMOG in glioblastoma cell line A172.
Hypoxia Inducible Factor 1α Inhibits the Expression of Immunosuppressive Tryptophan-2,3-Dioxygenase in Glioblastoma.
Cell line
View SamplesAltered daily patterns of hormone action are suspected to contribute to metabolic disease. It is poorly understood how the adrenal glucocorticoid hormones contribute to the coordination of daily global patterns of transcription and metabolism. Here, we examined diurnal metabolite and transcriptome patterns in a zebrafish glucocorticoid deficiency model by RNA-Seq, NMR spectroscopy and liquid chromatography-based methods. We observed dysregulation of metabolic pathways including glutaminolysis, the citrate and urea cycles and glyoxylate detoxification. Constant, non-rhythmic glucocorticoid treatment rescued many of these changes, with some notable exceptions among the amino acid related pathways. Surprisingly, the non-rhythmic glucocorticoid treatment rescued almost half of the entire dysregulated diurnal transcriptome patterns. A combination of E-box and glucocorticoid response elements is enriched in the rescued genes. This simple enhancer element combination is sufficient to drive rhythmic circadian reporter gene expression under non-rhythmic glucocorticoid exposure, revealing a permissive function for the hormones in glucocorticoid-dependent circadian transcription. Our work highlights metabolic pathways potentially contributing to morbidity in patients with glucocorticoid deficiency, even under glucocorticoid replacement therapy. Moreover, we provide mechanistic insight into the interaction between the circadian clock and glucocorticoids in the transcriptional regulation of metabolism. Overall design: RNA-Seq from total RNA of zebrafish larvae during (5 dpf) the diurnal cycle. Time-series mRNA profiles of untreated wild type (WT), rx3t25327/t25327 [rx3 strong] and rx3t25181/t25181 [rx3 weak] mutant larvae as well as dexamethasone treated WT and rx strong larvae were generated by deep sequencing.
Extensive Regulation of Diurnal Transcription and Metabolism by Glucocorticoids.
No sample metadata fields
View SamplesSulfite reductase (SiR) plays an essential role in the assimilatory sulfur reduction pathway by catalyzing the reduction of sulfite to sulfide. The T-DNA insertion mutant line sir1-1 shows lower amounts of SiR transcript, protein and lower activity and is severely affected in growth. In this study we performed global transcriptome analysis to investigate the impact of the mutation in the shoot of 7-week-old plants.
Sulfur availability regulates plant growth via glucose-TOR signaling.
Age
View SamplesThis SuperSeries is composed of the SubSeries listed below.
ACSL1 Is Associated With Fetal Programming of Insulin Sensitivity and Cellular Lipid Content.
Sex
View SamplesWe hypothesised that SGA as a proxy for intrauterine growth restriction promotes specific epigenetic marks and pathways, whose physiological implications may become apparent only in the fully differentiated state.
ACSL1 Is Associated With Fetal Programming of Insulin Sensitivity and Cellular Lipid Content.
Sex
View SamplesWe hypothesised that SGA as a proxy for intrauterine growth restriction promotes specific epigenetic marks and pathways, whose physiological implications may become apparent only in the fully differentiated state.
ACSL1 Is Associated With Fetal Programming of Insulin Sensitivity and Cellular Lipid Content.
Sex
View SamplesHistone deacetylase 1 (HDAC1) is an enzyme that promotes deacetylation of acetylated lysine residues in histones and other proteins. Histone acetylation is often associated with gene activation and expression. Los of HDAC1 leads to severe problems in development and proliferation. Moreover, it seems to be the major histone deacetylase in mouse embryonic stem cells.
Negative and positive regulation of gene expression by mouse histone deacetylase 1.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
BCAT1 restricts αKG levels in AML stem cells leading to IDHmut-like DNA hypermethylation.
Cell line, Treatment
View SamplesThe branched chain amino acid (BCAA) pathway and high levels of BCAA transaminase 1 (BCAT1) have recently been associated with aggressiveness in several cancer entities. However, the mechanistic role of BCAT1 in this process remains largely uncertain. By performing high-resolution proteomic analysis of human acute myeloid leukaemia (AML) stem cell (LSC) and non-LSC populations, we found the BCAA pathway enriched and BCAT1 overexpressed in LSCs. We show that BCAT1, which transfers -amino groups from BCAAs to -ketoglutarate (KG), is a critical regulator of intracellular KG homeostasis. Next to its role in the tricarboxylic acid (TCA) cycle KG is an essential co-factor for KG-dependent dioxygenases such as EGLN1 and the TET family of DNA demethylases. Knockdown of BCAT1 in leukaemia cells caused accumulation of KG leading to HIF1a protein degradation mediated by EGLN1. This resulted in a growth and survival defect and abrogated leukaemia-initiating potential. In contrast, overexpression (OE) of BCAT1 in leukaemia cells decreased intracellular KG levels and caused DNA hypermethylation via altered TET activity. BCAT1high AMLs displayed a DNA hypermethylation phenotype similar to cases carrying mutant isocitrate dehydrogenase (IDHmut), in which TET2 is inhibited by the oncometabolite 2-hydroxyglutarate. High levels of BCAT1 strongly correlate with shorter overall survival in IDHwtTET2wt, but not IDHmut or TET2mut AMLs. Gene sets characteristic for IDHmut AMLs were enriched in IDHwtTETwtBCAT1high patient samples. BCAT1high AMLs showed robust enrichment for LSC signatures and paired sample analysis revealed a significant increase of BCAT1 levels upon disease relapse. In summary, by limiting intracellular KG, BCAT1 links BCAA catabolism to HIF1a stability and regulation of the epigenomic landscape. Our results suggest the BCAA-BCAT1-KG pathway as a therapeutic target to compromise LSC function in IDHwtTET2wt AML patients.
BCAT1 restricts αKG levels in AML stem cells leading to IDHmut-like DNA hypermethylation.
Treatment
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