Transcriptional effects of glucocorticoid receptor alpha and beta signaling in zebrafish
Ontology highlight
ABSTRACT:
ORGANISM(S): Danio rerio
PROVIDER: GSE63360 | GEO | 2014/11/18
SECONDARY ACCESSION(S): PRJNA267561
REPOSITORIES: GEO
Similar Datasets
Project description:The glucocorticoid receptor (GR) regulates gene expression upon activation by glucocorticoid (GC) hormones. In zebrafish, two GR splice variants exist: the canonical GR M-NM-1-isoform (GRM-NM-1), and the GR M-NM-2-isoform (GRM-NM-2). The exact function of GRb remains elusive. We have investigated the transcriptional role of GRa and GRb in the zebrafish embryo model by injecting mebryos with two splice-blocking morpholinos (one leading to knockdown of both GR M-NM-1- and M-NM-2-isoforms, and another targeting the alternative splicing of the GR pre-mRNA in favor of the GR M-NM-2-isoform) and with GRM-NM-2 mRNA (resulting in specific GRM-NM-2 overexpression). Transcriptome profiling was performed on total RNA isolated from 30 hpf embryos. Our results show that GRb does not act as a dominant-negative inhibitor of GRa, and that GRa regulates two distinct gene clusters, which are mainly involved in the metabolism of the embryo. This microarray study was designed to determine the effect of knockdown and overexpression of GRa and GRb. For this purpose, wild type (AB/TL) zebrafish embryos were injected at the 1-2 cell stage with a standard control morpholino (SC-MO), a splice-blocking morpholino leading to knockdown of both GR M-NM-1- and M-NM-2-isoforms (MO1), a splice-blocking morpholino targeting the alternative splicing of the GR pre-mRNA in favor of the GR M-NM-2-isoform (MO2), or GRb mRNA. At 24 hpf, each group was treated with dexamathasone (or vehicle) for 6 hr. This resulted in 8 treament groups: SC-MO/veh, SC-MO/dex, MO1/veh, MO1/dex, MO2/veh, MO2/dex, GRb mRNA/veh, GRb mRNA/dex. After the incubation period, embryos were collected and RNA was isolated from 20 embryos per treatment group (30 hpf). Three individual experiments were performed, and the resulting triplicate samples were analyzed by microarray, using a common reference approach.
2014-11-18 | E-GEOD-63360 | biostudies-arrayexpress
Project description:Functional analysis of the zebrafish glucocorticoid receptor beta-isoform
| PRJNA335612 | ENA
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.
2018-04-23 | GSE103675 | GEO
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.
2019-02-15 | PXD012406 | Pride
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.
2019-02-15 | PXD012555 | Pride
Project description:Glucocorticoids regulate diverse physiologic processes and synthetic derivatives of these natural hormones are widely used in the treatment of inflammatory diseases. However, chronic administration often triggers insensitivity and serious side effects including osteoporosis. The underlying mechanisms regulating these side effects are not completely understood. We report here that human osteosarcoma U-2 OS bone cells lacking the glucocorticoid receptor (GR) are resistant to glucocorticoid killing whereas the expression of wild-type GR activates an apoptotic program. Furthermore, we show that the translationally generated GR isoforms from a single GR gene have distinct abilities to induce apoptosis in these cells. Only cells expressing selective GR isoforms underwent apoptosis upon dexamethasone treatment and microarray analysis demonstrated that GR isoforms selectively stimulated the expression of pro-apoptotic enzymes such as caspase 6 and granzyme A. Chromatin immunoprecipitation assays further revealed that GR isoform-dependent induction of pro-apoptotic genes is likely due to selective coregulator recruitment and chromatin modification. Together, these findings provide evidence for a direct apoptotic effect of glucocorticoids on bone cells via selective GR isoforms and delineate multiple molecular components involved in tissue-specific glucocorticoid-induced bone cell apoptosis. Keywords: time course, isoform comparison
2007-12-20 | GSE6711 | GEO
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.
2018-05-08 | GSE103721 | GEO
Project description:Glucocorticoids (GCs) bind to the glucocorticoid receptor (GR) to regulate diverse biological functions from cell growth to apoptosis. Drugs that mimic their action are the most commonly prescribed therapeutic agents in the world and are currently used for the treatment of many diseases including asthma, autoimmune disorders, and some cancers. However, the mechanisms by which one hormone, via one receptor, modulates such diverse biological functions remain unclear. We hypothesized that epigenetic alteration to the GR may contribute to its signaling diversity, and here we demonstrate that Glycogen Synthase Kinase-3-beta phosphorylates GR on Serine 404 in a glucocorticoid-dependent manner. U-2 OS cells expressing a mutant GR that is incapable of Ser404 phosphorylation have enhanced global transcriptional responses, stronger NF-kappaB transrepression, and enhanced cell death in response to dexamethasone. Conversely, presence of Ser404 phosphorylation on the GR inhibits glucocorticoid-dependent NF-kappaB transrepression and cell death of these osteoblasts. Collectively, our results describe a novel convergence point of the GSK-3-beta pathway with the GR resulting in altered glucocorticoid regulated signaling. Our results also provide a mechanism by which the phosphorylation status of Ser404 in GR can dictate how cells will ultimately respond to GCs. Keywords: Glucocorticoid Receptor; GSK-3-beta; NF-kappaB Transrepression; Phosphorylation
2008-11-24 | GSE11205 | GEO
Project description:Transcriptional effects of glucocorticoid receptor alpha and beta signaling in zebrafish
| PRJNA267561 | ENA
Project description:The Glucocorticoid Receptor (GR) co-ordinates metabolic and behavioural responses to stressors. We hypothesised that GR influences behaviour by modulating epigenetic and transcriptional processes in the brain. Using the zebrafish as a model organism, the brain methylomes of wild-type and grs357 mutant adults were analysed and GR-sensitive, differentially methylated regions (GR-DMRs) were identified. DMRs linked to genes with biologically salient functions were selected for confirmatory deep sequencing analysis in wild-type and GR mutant 5dpf larval heads, using the BisPCR2 technique (Bernstein et al., 2015). Our results demonstrate that the genes fkbp5 and aplp1 exemplify two distinct modes of GR-regulated, glucocorticoid-responsive DNA methylation in the brain.
2023-09-18 | GSE134810 | GEO