Ligand binding domain of nuclear hormone receptors:glucocorticoid receptor, mineralocorticoid receptor , progesterone receptor, and androgen receptor
The ligand binding domain of GR_like nuclear receptors: This family of NRs includes four distinct, but closely related nuclear hormone receptors: glucocorticoid receptor (GR), mineralocorticoid receptor (MR), progesterone receptor (PR), and androgen receptor (AR). These four receptors play key roles in some of the most fundamental physiological functions such as the stress response, metabolism, electrolyte homeostasis, immune function, growth, development, and reproduction. The NRs in this family use multiple signaling pathways and share similar functional mechanisms. The dominant signaling pathway is via direct DNA binding and transcriptional regulation of target genes. Another mechanism is via protein-protein interactions, mainly with other transcription factors such as nuclear factor-kappaB and activator protein-1, to regulate gene expression patterns. Both pathways can up-regulate or down-regulate gene expression and require ligand activation of the receptor and recruitment of other cofactors such as chaperone proteins and coregulator proteins. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, GR, MR, PR, and AR share the same modular structure with a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a flexible hinge and a C-terminal ligand binding domain (LBD).