ACTH receptor
The adrenocorticotropic hormone receptor or ACTH receptor also known as the melanocortin receptor 2 or MC2 receptor is a type of melanocortin receptor (type 2) which is specific for ACTH.
Structure
Both human and bovine ACTH receptors are synthesized as 297 residue long proteins. There is 81% homology between human and bovine sequences. The full length sequence includes seven hydrophobic domains that are predicted as transmembrane segments. In the third intracellular loop of the receptor a protein kinase A and protein kinase c phosphorylation motifs have been detected.
Tissue and subcellular localization
ACTH receptor is found in the zona fasciculata of the human adrenal cortex. Binding of the receptor by ACTH stimulates the production of cortisol. (By contrast, aldosterone production from the zona glomerulosa is stimulated primarily by angiotensin II.)
Protein recognition at the receptor uses energy obtained from the dephosphorylation of ATP to cAMP by adenylate cyclase. ACTH receptors are located on the plasma membrane, and are G protein-coupled receptors.
Podcasts:
