NR3C1 Antibody

Description: Glucocorticoid hormones control cellular proliferation, inflammation, and metabolism through their association with the glucocorticoid receptor (GR)/NR3C1, a member of the nuclear hormone receptor superfamily of transcription factors (1). GR is composed of several conserved structural elements, including a carboxy-terminal ligand-binding domain (which also contains residues critical for receptor dimerization and hormone-dependent gene transactivation), a neighboring hinge region containing nuclear localization signals, a central zinc-finger-containing DNA-binding domain, and an amino-terminal variable region that participates in ligand-independent gene transcription. In the absence of hormone, a significant population of GR is localized to the cytoplasm in an inactive form via its association with regulatory chaperone proteins, such as HSP90, HSP70, and FKBP52. On hormone binding, GR is released from the chaperone complex and translocates to the nucleus as a dimer to associate with specific DNA sequences termed glucocorticoid response elements (GREs), thereby enhancing or repressing transcription of specific target genes (2). It was demonstrated that GR-mediated transcriptional activation is modulated by phosphorylation (3-5). Although GR can be basally phosphorylated in the absence of hormone, it becomes hyperphosphorylated upon binding receptor agonists. It has been suggested that hormone-dependent phosphorylation of GR may determine target promoter specificity, cofactor interaction, strength and duration of receptor signaling, receptor stability, and receptor subcellular localization (3). Indeed Ser211 of human GR is phosphorylated to a greater extent in the presence of hormone, and biochemical fractionation studies following hormone treatment indicate that Ser211-phosphorylated GR is found in the nucleus (3). Thus, Ser211 phosphorylation is a biomarker for activated GR in vivo. An added layer of complexity to GR signaling lies in the ability of multiple isoforms to be generated through both alternative splicing and the use of alternative translation intiation start sites, thus increasing the repertoire of functional signaling homo-and heterodimers (6, 7).
Function: Receptor for glucocorticoids (GC) (PubMed:27120390). Has a dual mode of action: as a transcription factor that binds to glucocorticoid response elements (GRE), both for nuclear and mitochondrial DNA, and as a modulator of other transcription factors. Affects inflammatory responses, cellular proliferation and differentiation in target tissues. Involved in chromatin remodeling (PubMed:9590696). Plays a role in rapid mRNA degradation by binding to the 5' UTR of target mRNAs and interacting with PNRC2 in a ligand-dependent manner which recruits the RNA helicase UPF1 and the mRNA-decapping enzyme DCP1A, leading to RNA decay (PubMed:25775514). Could act as a coactivator for STAT5-dependent transcription upon growth hormone (GH) stimulation and could reveal an essential role of hepatic GR in the control of body growth (By similarity).
Subunit Structure: Heteromultimeric cytoplasmic complex with HSP90AA1, HSPA1A/HSPA1B, and FKBP5 or another immunophilin such as PPID, STIP1, or the immunophilin homolog PPP5C (PubMed:21730050). Upon ligand binding FKBP5 dissociates from the complex and FKBP4 takes its place, thereby linking the complex to dynein and mediating transport to the nucleus, where the complex dissociates (By similarity). Probably forms a complex composed of chaperones HSP90 and HSP70, co-chaperones CDC37, PPP5C, TSC1 and client protein TSC2, CDK4, AKT, RAF1 and NR3C1; this complex does not contain co-chaperones STIP1/HOP and PTGES3/p23 (PubMed:29127155). Directly interacts with UNC45A (PubMed:16478993). Binds to DNA as a homodimer, and as heterodimer with NR3C2 or the retinoid X receptor. Binds STAT5A and STAT5B homodimers and heterodimers (By similarity). Interacts with NRIP1, POU2F1, POU2F2 and TRIM28 (By similarity). Interacts with several coactivator complexes, including the SMARCA4 complex, CREBBP/EP300, TADA2L (Ada complex) and p160 coactivators such as NCOA2 and NCOA6 (PubMed:10866662, PubMed:12151000, PubMed:12686538, PubMed:9154805, PubMed:9590696). Interaction with BAG1 inhibits transactivation (PubMed:10477749). Interacts with HEXIM1, PELP1 and TGFB1I1 (PubMed:12415108, PubMed:15211577, PubMed:15941832). Interacts with NCOA1 (PubMed:9590696). Interacts with NCOA3, SMARCA4, SMARCC1, SMARCD1, and SMARCE1 (By similarity). Interacts with CLOCK, CRY1 and CRY2 in a ligand-dependent fashion (PubMed:19141540, PubMed:21980503, PubMed:22170608). Interacts with CIART (By similarity). Interacts with RWDD3 (By similarity). Interacts with UBE2I/UBC9 and this interaction is enhanced in the presence of RWDD3 (By similarity). Interacts with GRIP1 (PubMed:15769988, PubMed:17635946). Interacts with NR4A3 (via nuclear receptor DNA-binding domain), represses transcription activity of NR4A3 on the POMC promoter Nur response element (NurRE) (PubMed:15591535). Directly interacts with PNRC2 to attract and form a complex with UPF1 and DCP1A; the interaction leads to rapid mRNA degradation (PubMed:25775514). Interacts with GSK3B (PubMed:18838540). Interacts with FNIP1 and FNIP2 (PubMed:27353360). Interacts (via C-terminus) with HNRNPU (via C-terminus) (PubMed:9353307).
Post-translational Modifications: Acetylation by CLOCK reduces its binding to glucocorticoid response elements and its transcriptional activity.Increased proteasome-mediated degradation in response to glucocorticoids (PubMed:11555652). Isoform Alpha-B appears to be more susceptible to proteolytic degradation than isoform Alpha (PubMed:11435610). Phosphorylated in the absence of hormone; becomes hyperphosphorylated in the presence of glucocorticoid. The Ser-203, Ser-226 and Ser-404-phosphorylated forms are mainly cytoplasmic, and the Ser-211-phosphorylated form is nuclear (PubMed:12000743, PubMed:18838540). Phosphorylation at Ser-211 increases transcriptional activity (PubMed:12000743, PubMed:18483179). Phosphorylation at Ser-203, Ser-226 and Ser-404 decreases signaling capacity (PubMed:12000743, PubMed:18483179, PubMed:18838540). Phosphorylation at Ser-404 may protect from glucocorticoid-induced apoptosis (PubMed:18838540). Phosphorylation at Ser-203 and Ser-211 is not required in regulation of chromosome segregation (PubMed:25847991). May be dephosphorylated by PPP5C, attenuates NR3C1 action (By similarity). Sumoylation at Lys-277 and Lys-293 negatively regulates its transcriptional activity (PubMed:12144530). Sumoylation at Lys-703 positively regulates its transcriptional activity in the presence of RWDD3 (By similarity). Sumoylation at Lys-277 and Lys-293 is dispensable whereas sumoylation at Lys-703 is critical for the stimulatory effect of RWDD3 on its transcriptional activity (By similarity). Heat shock increases sumoylation in a RWDD3-dependent manner (By similarity). Ubiquitinated; restricts glucocorticoid-mediated transcriptional signaling.
Similarity: Composed of three domains: a modulating N-terminal domain, a DNA-binding domain and a C-terminal ligand-binding domain (PubMed:3841189). The ligand-binding domain is required for correct chromosome segregation during mitosis although ligand binding is not required (PubMed:25847991). Belongs to the nuclear hormone receptor family. NR3 subfamily.