The relaxin peptide family--structure, function and clinical applications

Linda Chan, Mohammed Hossain, Chrishan Samuel, Frances Separovic, Johh Wade

Research output: Contribution to journalArticleResearchpeer-review

44 Citations (Scopus)


The relaxin peptide family in humans consists of seven members, relaxin-1, -2 and -3 and insulin-like (INSL) peptides 3, 4, 5 and 6. It is an offshoot of the large insulin superfamily. Each member consists of two chains, commonly referred to as A and B, which are held together by two inter-chain disulfide bonds and another intra-chain disulfide bond present within the A chain. The cysteine residues present in each chain, together with the distinctive disulfide bonding pattern, are conserved across all members of the superfamily. The chemical synthesis of these complex peptides poses a significant challenge. In the past, random combination of the two synthetic S-reduced chains under oxidizing conditions was utilized to form the three disulfide bonds. Nowadays, with the aid of highly efficient solid phase peptide synthesis methodologies, in conjunction with selective S-thiol-protecting groups, combination of individual A- and B- chains by sequential chemical formation of each of the three disulfide bonds is now possible resulting in good yields of these peptides. The relaxin peptide family members bind to G-protein coupled receptors (GPCRs) which have been classified as relaxin family peptide (RXFP) receptors. The various unique receptor-ligand interactions are outlined in this review, together with the physiological roles of the relaxin peptide family members and lastly their past and present clinical applications.
Original languageEnglish
Pages (from-to)220 - 229
Number of pages10
JournalProtein and Peptide Letters
Issue number3
Publication statusPublished - 2011
Externally publishedYes

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