Rat Melanocortin receptor (MC4-R) is a 332 amino acid transmembrane protein belonging to the family of G-Protein coupled receptors. It is a receptor for MSH (a,b,g) and ACTH. It is found in brain, placenta, and gut tissues. Anti-Human MC4-R antibodies were raised against 14 aa peptide mapping near c-terminal 4th cytoplasmic domain of human MC4-R. The peptide was coup led with KLH (carrier protein) and antibodies generated in rabbits. The control peptide has been used to affinity purify the antibodies. 64% (9/14 aa) homologous with rat MC4-R. No significant sequence homology of mCR42 is seen with other melanocortin receptors.
Melanocortins are regulatory peptides formed by post-translational processing of pro-opiomelanocortin. Melanocortin peptides have been suggested to perform a variety of physiological roles ranging from control of behavior, memory, neurotrophic properties, antipyretic and modulation of immune system, etc. Their binding sites have been found distributed in tissues ranging from lachrymal and submandibular glands, pancreas, adipose tissue, bladder, duodenum, spleen, brain, gonadal tissues and malignant melanoma tumors. Five melanocortin receptors have been characterized to date. These include melanocyte-stimulating hormone receptor (MSH or MC1-R), corticoaderenal-specific ACTH receptor (MC2-R), melacortin-3 (MC3-R), melanocortin-4 (MC4-R) and melanocortin-5 receptor (MC5-R). MC3-R and MC4-R are distributed in brain whereas MC5-R has a broad distribution.
