MRGX2 is a G-protein coupled receptor that may regulate nociceptor function and development, including the sensation or modulation of pain. Cortistatin-14 seems to be a high potency ligand at this receptor. Cortistatin has several biological functions including roles in sleep regulation locomotor activity, and cortical function. It has been reported to be expressed in regions of the brain, pituitary, thyroid, pancreas, testis, and ovary, as well as in neuroendocrine tumors. References: J Pathol 2005; 207: 336–345