Relaxin-3

Relaxin-3 (H3 relaxin, Insulin-like peptide-7, INSL7) is a secreted protein structurally related to insulin, which is expressed primarily in the brain and central nervous system. Relaxin-3 has been identified as the ligand for the GPCR135 receptor, previously known as “somatostatin-like” or “angiotensin-like” peptide receptor, and also binds specifically to the LGR7 receptor, previously identified as an “orphan” G protein coupled receptor. Signaling by Relaxin-3 through its target receptors is, most likely, part of a CNS processing system, activated in response to signaling by neuropeptides and other factors. Intracerebroventricular injections of Relaxin-3 have been shown to cause a significant increase of food intake and body weight in Wistar rats. Recombinant Relaxin-3 is a 5.5 kDa disulfide linked heterodimeric protein consisting of a 24 amino acid A-chain and a 27 amino acid B-chain.