title: Relaxin family peptides: structure-activity relationship studies.
abstract: The human relaxin peptide family consists of seven cystine-rich peptides, four of which are known to signal through relaxin family peptide receptors, RXFP1-4. As these peptides play a vital role physiologically and in various diseases, they are of considerable importance for drug discovery and development. Detailed structure-activity relationship (SAR) studies towards understanding the role of important residues in each of these peptides have been reported over the years and utilized for the design of antagonists and minimized agonist variants. This review summarizes the current knowledge of the SAR of human relaxin 2 (H2 relaxin), human relaxin 3 (H3 relaxin), human insulin-like peptide 3 (INSL3) and human insulin-like peptide 5 (INSL5).
  
  
  
  This article is part of a themed section on Recent Progress in the Understanding of Relaxin Family Peptides and their Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.10/issuetoc.
authors.affiliation: The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia.|School of Chemistry, University of Melbourne, Parkville, VIC, Australia.
authors.forename: Nitin A
authors.initials: NA
authors.lastname: Patil
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, Australia.
authors.forename: K Johan
authors.initials: KJ
authors.lastname: Rosengren
authors.affiliation: School of Chemistry, University of Melbourne, Parkville, VIC, Australia.
authors.forename: Frances
authors.identifier: 0000-0002-6484-2763
authors.initials: F
authors.lastname: Separovic
authors.affiliation: The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia.|School of Chemistry, University of Melbourne, Parkville, VIC, Australia.
authors.forename: John D
authors.initials: JD
authors.lastname: Wade
authors.affiliation: The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia.|Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, Australia.
authors.forename: Ross A D
authors.initials: RAD
authors.lastname: Bathgate
authors.affiliation: The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia.|School of Chemistry, University of Melbourne, Parkville, VIC, Australia.
authors.forename: Mohammed Akhter
authors.identifier: 0000-0002-9961-0006
authors.initials: MA
authors.lastname: Hossain
mesh_terms: D006801:Humans; D007328:Insulin / Q000737:chemistry*; D008958:Models, Molecular; D011506:Proteins / Q000737:chemistry*; D012065:Relaxin / Q000031:analogs & derivatives* / Q000737:chemistry; D013329:Structure-Activity Relationship
chemical_list: D007328:Insulin; C084797:Leydig insulin-like protein; D011506:Proteins; C095068:RLN2 protein, human; C480238:RLN3 protein, human; D012065:Relaxin