The GR is a modular protein containing an N-terminal transactivation domain (NTD), a central DNA-binding domain (DBD), a C-terminal ligand-binding domain (LBD), and a flexible ‘hinge region’ separating the DBD and the LBD. Glucocorticoid-bound GR binds to these simple GREs to mediate transactivation, rather than transrepression, by recruiting coactivators and chromatin-remodeling complexes. GR also binds a half-GRE site on TTP, an mRNA-destabilizing gene, to decrease gene expression of proinflammatory cytokines. GREs recruit other transcription factors that in turn are bound to the GR. For example, suppression of inflammation in diseases such as asthma and COPD occurs by GR tethering with proinflammatory transcription factors such as activator protein-1 (AP-1), nuclear factor kappa B (NF-kB), and signal transducer and activator of transcription 3 (STAT3). 
Phosphorylation of GRs has occured on several serine residues (S113, S134, S141, S143, S203, S211, S226, and S404) by numerous kinases including cyclin-dependent kinase, MAPK, glycogen synthase kinase-3 (GSK-3), and casein kinase II. GR can be acetylated on lysines 494 and 495 in response to glucocorticoids, and this modification correlates with impaired ability of the GR to inhibit the actions of NF-kB. GR isoforms are expressed in nearly all tissue types and glucocorticoid signaling is almost ubiquitously prevalentin the various organ systems. Due to their anti-inflammatory, antiproliferative, proapoptotic, and antiangiogenic roles, glucocorticoids have been remarkably effective in treating various diseases and have been at the forefront of basic science and pharmaceutical research for the past few decades.


1.Kadmiel M and Cidlowski JA. Trends Pharmacol Sci. 2013;34(9):518–530.