Mineralocorticoid Receptor (MR) is a member of the nuclear hormone receptor family. Upon binding of ligand (aldosterone or corticosterone) mineralocorticoid receptors translocate to the nucleus and can form either homo or heterodimers. MR dimers bind to the mineralocorticoid response element (AGAACANNNTGTTCT) to regulate gene transcription. There are four known isoforms of MR.
Mineralocorticoid Receptos are expressed in the kidney, gut, brain, pituitary, hypothalamus and heart. MR plays a critical role in regulating electrolyte and fluid balance in the kidney, as well as having specific roles in the central nervous system. The protein is expressed as a 107 kDa nuclear form. MR and glucocorticoid receptors (GR) can cooperatively form heterodimers.