title: Development of a Single-Chain Peptide Agonist of the Relaxin-3 Receptor Using Hydrocarbon Stapling.
abstract: Structure-activity studies of the insulin superfamily member, relaxin-3, have shown that its G protein-coupled receptor (RXFP3) binding site is contained within its central B-chain α-helix and this helical structure is essential for receptor activation. We sought to develop a single B-chain mimetic that retained agonist activity. This was achieved by use of solid phase peptide synthesis together with on-resin ruthenium-catalyzed ring closure metathesis of a pair of judiciously placed i,i+4 α-methyl, α-alkenyl amino acids. The resulting hydrocarbon stapled peptide was shown by solution NMR spectroscopy to mimic the native helical conformation of relaxin-3 and to possess potent RXFP3 receptor binding and activation. Alternative stapling procedures were unsuccessful, highlighting the critical need to carefully consider both the peptide sequence and stapling methodology for optimal outcomes. Our result is the first successful minimization of an insulin-like peptide to a single-chain α-helical peptide agonist which will facilitate study of the function of relaxin-3.
authors.affiliation: Faculty of Pharmaceutical Sciences and Cooperative Research Center of Life Sciences, Kobe Gakuin University , Chuo-ku, Kobe 650-8586, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Hojo
authors.affiliation: Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.|School of Chemistry, University of Melbourne , Melbourne, Victoria 3052, Australia.
authors.forename: Mohammed Akhter
authors.initials: MA
authors.lastname: Hossain
authors.affiliation: Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.
authors.forename: Julien
authors.initials: J
authors.lastname: Tailhades
authors.affiliation: Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.|School of Chemistry, University of Melbourne , Melbourne, Victoria 3052, Australia.
authors.forename: Fazel
authors.initials: F
authors.lastname: Shabanpoor
authors.affiliation: Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.
authors.forename: Lilian L L
authors.initials: LL
authors.lastname: Wong
authors.affiliation: Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.
authors.forename: Emma E K
authors.initials: EE
authors.lastname: Ong-Pålsson
authors.affiliation: Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.
authors.forename: Hanna E
authors.initials: HE
authors.lastname: Kastman
authors.affiliation: Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.
authors.forename: Sherie
authors.initials: S
authors.lastname: Ma
authors.affiliation: Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.|Department of Anatomy and Neuroscience, University of Melbourne , Melbourne, Victoria 3052, Australia.
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Gundlach
authors.affiliation: School of Biomedical Sciences, The University of Queensland , Brisbane, Queensland 4072, Australia.
authors.forename: K Johan
authors.initials: KJ
authors.lastname: Rosengren
authors.affiliation: Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.|School of Chemistry, University of Melbourne , Melbourne, Victoria 3052, Australia.
authors.forename: John D
authors.initials: JD
authors.lastname: Wade
authors.affiliation: Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.|Department of Biochemistry and Molecular Biology, University of Melbourne , Melbourne, Victoria 3052, Australia.
authors.forename: Ross A D
authors.initials: RA
authors.lastname: Bathgate
mesh_terms: D000818:Animals; D002460:Cell Line; D003412:Cricetulus; D004305:Dose-Response Relationship, Drug; D006801:Humans; D006838:Hydrocarbons / Q000737:chemistry / Q000494:pharmacology*; D008297:Male; D008958:Models, Molecular; D015394:Molecular Structure; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012065:Relaxin / Q000819:agonists*; D013329:Structure-Activity Relationship
chemical_list: D006838:Hydrocarbons; D010455:Peptides; C480238:RLN3 protein, human; D012065:Relaxin