Project description:The glucocorticoid receptor (GR) is a nuclear hormone receptor critical to the regulation of energy metabolism and the inflammatory response. The actions of GR have been shown to be highly dependent on context. Here, we performed GR ChIP-seq in mouse liver to demonstrate the necessity for liver lineage-determining factor hepatocyte nuclear factor 4A (HNF4A) in defining tissue-specificity of GR action. In normal liver, the HNF4 motif lies adjacent to the glucocorticoid response element (GRE) at GR binding sites found within regions of open chromatin. In the absence of HNF4A, the liver GR cistrome is remodelled, with both loss and gain of GR recruitment evident. Lost sites are characterised by HNF4 motifs and weak GRE motifs. Gained sites are characterised by strong GRE motifs, and typically show GR recruitment in non-liver tissues. The functional importance of these HNF4A-regulated GR sites is further demonstrated by evidence of an altered transcriptional response to glucocorticoid treatment in the Hnf4a-null liver.
Project description:The glucocorticoid receptor (GR) is a nuclear hormone receptor critical to the regulation of energy metabolism and the inflammatory response. The actions of GR are highly dependent on cell type and environmental context. Here, we demonstrate the necessity for liver lineage-determining factor hepatocyte nuclear factor 4A (HNF4A) in defining liver-specificity of GR action. In normal mouse liver, the HNF4 motif lies adjacent to the glucocorticoid response element (GRE) at GR binding sites found within regions of open chromatin. In the absence of HNF4A, the liver GR cistrome is remodelled, with both loss and gain of GR recruitment evident. Loss of chromatin accessibility at HNF4A-marked sites leads to loss of GR binding at weak GRE motifs. GR binding is gained at sites characterised by strong GRE motifs, which typically show GR recruitment in non-liver tissues. The functional importance of these HNF4A-regulated GR sites is further demonstrated by evidence of an altered transcriptional response to glucocorticoid treatment in the Hnf4a-null liver.
Project description:The glucocorticoid receptor (GR) is a nuclear hormone receptor critical to the regulation of energy metabolism and the inflammatory response. The actions of GR have been shown to be highly dependent on context. Here, we demonstrate the necessity for liver lineage-determining factor hepatocyte nuclear factor 4A (HNF4A) in defining tissue-specificity of GR action. In normal liver, the HNF4 motif lies adjacent to the glucocorticoid response element (GRE) at GR binding sites found within regions of open chromatin. In the absence of HNF4A, the liver GR cistrome is remodelled, with both loss and gain of GR recruitment evident. Lost sites are characterised by HNF4 motifs and weak GRE motifs. Gained sites are characterised by strong GRE motifs, and typically show GR recruitment in non-liver tissues. These RNA-seq data demonstrate the functional importance of these HNF4A-regulated GR sites by showing evidence of an altered transcriptional response to glucocorticoid treatment in the Hnf4a-null liver. In Hnf6-null liver, a far more minor effect on the glucocorticoid response is observed.
Project description:DNase-seq and ChIP-seq determine that C/EBP maintains chromatin accessibility in liver and facilitates glucocorticoid receptor recruitment to steroid response elements DNase-seq and ChIP-seq (GR, C/EBPb and RNAPII) in intact liver from adrenalectomized mice injected with dex (1h)
Project description:Macrophages are amongst the major targets of glucocorticoids (GC) as therapeutic anti-inflammatory agents. Here we show that GC treatment of mouse and human macrophages initiates a cascade of induced gene expression including many anti-inflammatory genes. Inducible binding of the glucocorticoid receptor (GR) was detected at candidate enhancers in the vicinity of induced genes in both species and this was strongly associated with canonical GR binding motifs. However, the sets of inducible genes, the candidate enhancers, and the GR motifs within them, were highly-divergent between the two species. Mouse bone marrow derived macrophages were generated from two male 10 week old C57BL/6 mice, treated with dexamethsone 100nM or vehicle and glucocorticoid receptor bound DNA extracted by chromatin immunoprecipitation
Project description:Here we show how chromatin structure is involved in glucocorticoid receptor (GR) binding in a mouse mammary cell line. We show that GR binds to accessible chromatin sites that are either nucleosome-free or contain a nucleosome.
Project description:To identify the sequences responsible for recruitment of Glucocorticoid receptor (GR) to individual loci, we performed ChIP-seq in four cell lines : A549 (ATTC:CCL-185), Nalm-6 (ATCC:CRL-1567), immortalized mouse embryonic fibroblasts (MEFs)(PMID 21131905), and immortalized PCAF-/-; GCN5flox/ MEFs (PMID 21131905) upon glucocorticoid treatment (1.5 hrs, 1M dexamethasone).
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.