Open AccessRelaxin family peptide receptors in GtoPdb v.2021.3
Author(s) -
Ross A. D. Bathgate,
Thomas Dschietzig,
Andrew L. Gundlach,
Michelle L. Halls,
Roger J. Summers
Publication year - 2021
Publication title -
iuphar/bps guide to pharmacology cite
Language(s) - English
Resource type - Journals
ISSN - 2633-1020
DOI - 10.2218/gtopdb/f60/2021.3
Subject(s) - relaxin , receptor , peptide , ligand (biochemistry) , chemistry , g protein coupled receptor , antagonist , biology , biochemistry , microbiology and biotechnology
Relaxin family peptide receptors (RXFP, nomenclature as agreed by the NC-IUPHAR Subcommittee on Relaxin family peptide receptors [18, 81]) may be divided into two pairs, RXFP1/2 and RXFP3/4. Endogenous agonists at these receptors are heterodimeric peptide hormones structurally related to insulin: relaxin-1, relaxin, relaxin-3 (also known as INSL7), insulin-like peptide 3 (INSL3) and INSL5. Species homologues of relaxin have distinct pharmacology and relaxin interacts with RXFP1, RXFP2 and RXFP3, whereas mouse and rat relaxin selectively bind to and activate RXFP1 [184]. relaxin-3 is the ligand for RXFP3 but it also binds to RXFP1 and RXFP4 and has differential affinity for RXFP2 between species [183]. INSL5 is the ligand for RXFP4 but is a weak antagonist of RXFP3. relaxin and INSL3 have multiple complex binding interactions with RXFP1 [189] and RXFP2 [91] which direct the N-terminal LDLa modules of the receptors together with a linker domain to act as a tethered ligand to direct receptor signaling [186]. INSL5 and relaxin-3 interact with their receptors using distinct residues in their B-chains for binding, and activation, respectively [225, 104].