Project description:To identify the genes regulated by the Glucocorticoid Receptor (GR), we performed RNA-seq in GR18 cell line (derived from U2OS ATTC:HTB-96, stably transfected with an expression construct for GR), upon glucocorticoid (dexamethasone) or vehicle (ethanol) treatment.
Project description:To identify the genes regulated by the Glucocorticoid Receptor (GR), we performed RNA-seq in GR18 cell line (derived from U2OS ATTC:HTB-96, stably transfected with an expression construct for GR), upon glucocorticoid (dexamethasone) or vehicle (ethanol) treatment for 24 hours.
Project description:To identify the sequences responsible for recruitment of Glucocorticoid receptor (GR) to individual loci, we performed BeadArray gene expression analysis in IMR90 cell line (ATTC:CCL-186), upon glucocorticoid treatment.
Project description:ARGLU1 is a Transcriptional Coactivator and Splicing Regulator Important for Stress Hormone Signaling and Development Stress hormones bind and activate the glucocorticoid receptor (GR) in many tissues including the brain. We identified arginine and glutamate rich 1 (ARGLU1) in a screen for new modulators of glucocorticoid signaling in the CNS. Biochemical studies show that the glutamate rich C-terminus of ARGLU1 coactivates multiple nuclear receptors including the glucocorticoid receptor (GR) and the arginine rich N-terminus interacts with splicing factors and binds to RNA. RNA-seq of neuronal cells depleted of ARGLU1 revealed significant changes in the expression and alternative splicing of distinct genes involved in neurogenesis. Loss of ARGLU1 is embryonic lethal in mice, and knockdown in zebrafish causes neurodevelopmental and heart defects. Treatment with dexamethasone, a GR activator, also induces changes in the pattern of alternatively spliced genes, many of which were lost when ARGLU1 was absent. Importantly, the genes found to be alternatively spliced in response to glucocorticoid treatment were distinct from those under transcriptional control by GR, suggesting an additional mechanism of glucocorticoid action is present in neuronal cells. Our results thus show that ARGLU1 is a novel factor for embryonic development that modulates basal transcription and alternative splicing in neuronal cells with consequences for glucocorticoid signaling.
Project description:ARGLU1 is a Transcriptional Coactivator and Splicing Regulator Important for Stress Hormone Signaling and Development Stress hormones bind and activate the glucocorticoid receptor (GR) in many tissues including the brain. We identified arginine and glutamate rich 1 (ARGLU1) in a screen for new modulators of glucocorticoid signaling in the CNS. Biochemical studies show that the glutamate rich C-terminus of ARGLU1 coactivates multiple nuclear receptors including the glucocorticoid receptor (GR) and the arginine rich N-terminus interacts with splicing factors and binds to RNA. RNA-seq of neuronal cells depleted of ARGLU1 revealed significant changes in the expression and alternative splicing of distinct genes involved in neurogenesis. Loss of ARGLU1 is embryonic lethal in mice, and knockdown in zebrafish causes neurodevelopmental and heart defects. Treatment with dexamethasone, a GR activator, also induces changes in the pattern of alternatively spliced genes, many of which were lost when ARGLU1 was absent. Importantly, the genes found to be alternatively spliced in response to glucocorticoid treatment were distinct from those under transcriptional control by GR, suggesting an additional mechanism of glucocorticoid action is present in neuronal cells. Our results thus show that ARGLU1 is a novel factor for embryonic development that modulates basal transcription and alternative splicing in neuronal cells with consequences for glucocorticoid signaling.
Project description:Glucocorticoid resistance is a major driver of therapeutic failure in T-cell acute lymphoblastic leukemia (T-ALL). Here we identify the AKT1 kinase as a signaling factor driving glucocorticoid resistance in T-ALL. Mechanistically, AKT1 directly phosphorylates the glucocorticoid receptor NR3C1 protein and blocks glucocorticoid-induced NR3C1 transcription by inhibiting glucocorticoid-induced NT3C1 translocation to the nucleus. Consistently, pharmacologic inhibition of AKT1 increases the response of T-ALL cells to glucocorticoid therapy and effectively reverses glucocorticoid resistance in vitro and in vivo. These results warrant the clinical testing of AKT1 inhibitors and glucocorticoids in combination for the treatment of T-ALL. Gene Expression Analysis of DND41 cell lines infected with shPTEN or shLUC and treated with 1M-BM-5M Dexamethasone vs DMSO for 24h, in triplicate.