Project description:Glucocorticoids are primary stress hormones and their synthetic derivatives are widely used clinically. The therapeutic efficacy of these steroids is limited by severe side effects and glucocorticoid resistance. Multiple glucocorticoid receptor (GR) isoforms are produced by alternative translation initiation; however, the role individual isoforms play in controlling tissue-specific responses to glucocorticoids in vivo is unknown. We have generated knockin mice that exclusively express the most active receptor isoform, GR-C3. The GR-C3 knockin mice die at birth due to respiratory distress but can be completely rescued by antenatal glucocorticoid administration. To evaluate the GR-C3 transcriptome, we prepared mouse embryonic fibroblasts (MEFs) from E12.5 wild-type (WT) and GR-C3 knockin embryos and treated the cells with vehicle or the synthetic glucocorticoid Dexamethasone (Dex) for 6 hours. The GR-C3 isoform was found to have a markedly different gene-regulatory profile than GR in WT MEFs.
Project description:Glucocorticoids are primary stress hormones and their synthetic derivatives are widely used clinically. The therapeutic efficacy of these steroids is limited by severe side effects and glucocorticoid resistance. Multiple glucocorticoid receptor (GR) isoforms are produced by alternative translation initiation; however, the role individual isoforms play in controlling tissue-specific responses to glucocorticoids in vivo is unknown. We have generated knockin mice that exclusively express the most active receptor isoform, GR-C3. The GR-C3 knockin mice die at birth due to respiratory distress but can be completely rescued by antenatal glucocorticoid administration. Rescued GR-C3 mice exhibited alterations in circadian rhythm in a sexually dimorphic manner and in sensitivity to lipopolysaccharide (LPS)-induced endotoxemia. To evaluate the ability of glucocorticoids to protect against LPS-induced inflammation, we measured gene expression in spleens from WT and rescued GR-C3 knockin mice that had been treated with vehicle or LPS for 3 and 24 hours. The GR-C3 isoform was found to be deficient in its ability to repress a large cohort of immune and inflammatory genes.
Project description:Transcription profiling by array of mouse embryonic fibroblasts from p27 -/- knockouts and wild-type controls to study the role of p27 in regulating the cell cycle
Project description:We performed RNA sequencing in Mouse Embryonic Fibroblasts (MEFs) of GR wild-type and GR Zn. Cells were treated with: vehicle (EtOH), Dexamethasone (Dex), Lipopolysaccharide (LPS) or Dex+LPS. We show that GR Zn does not regulate any GR target gene
Project description:Transcriptional profiling of mouse primary embryonic fibroblasts (MEFs) from wild type (WT) and knockin littermates expressing STAT1F77A (KI). For both genotypes, untreated control cells were compared to cells treated with IFN-alpha or IFN-gamma.
Project description:We performed ChIP-Sequencing for GR in GR wild-type, GR Zn mutant and GR Knock-Out Mouse Embryonic Fibroblasts (MEFs). We show that GR Zn mutant chromatin binding is mostly lost except for some tethered binding sites. Together with the corresponding RNA-Seq data, our results illustrate how GR requires direct DNA binding for activation and repression of target genes.
