title: Engineering of a Novel Simplified Human Insulin-Like Peptide 5 Agonist.
abstract: Insulin-like peptide 5 (INSL5) has recently been discovered as only the second orexigenic gut hormone after ghrelin. As we have previously reported, INSL5 is extremely difficult to assemble and oxidize into its two-chain three-disulfide structure. The focus of this study was to generate structure-activity relationships (SARs) of INSL5 and use it to develop a potent and simpler INSL5 mimetic with RXFP4 agonist activity. A series of human and mouse INSL5 (hINSL5/mINSL5) analogues were designed and chemically synthesized, resulting in a chimeric INSL5 analogue exhibiting more than 10-fold higher potency (0.35 nM) at human RXFP4 compared with native hINSL5 (4.57 nM). The SAR study also identified a key residue (K(A15)) in the A-chain of mINSL5 that contributes to improved RXFP4 affinity and potency of mINSL5 compared with hINSL5. This knowledge ultimately led us to engineer a minimized hINSL5 mimetic agonist that retains native hINSL5-like RXFP4 affinity and potency at human RXFP4. This minimized analogue was synthesized in 17.5-fold higher yield and in less time compared with hINSL5.
authors.forename: Nitin A
authors.initials: NA
authors.lastname: Patil
authors.forename: Richard A
authors.initials: RA
authors.lastname: Hughes
authors.affiliation: School of Biomedical Sciences, The University of Queensland , Brisbane, QLD 4072, Australia.
authors.forename: K Johan
authors.initials: KJ
authors.lastname: Rosengren
authors.affiliation: Monash Institute of Pharmaceutical Sciences, Monash University , Parkville, VIC 3052, Australia.
authors.forename: Martina
authors.initials: M
authors.lastname: Kocan
authors.affiliation: Monash Institute of Pharmaceutical Sciences, Monash University , Parkville, VIC 3052, Australia.
authors.forename: Sheng Yu
authors.initials: SY
authors.lastname: Ang
authors.forename: Julien
authors.initials: J
authors.lastname: Tailhades
authors.forename: Frances
authors.initials: F
authors.lastname: Separovic
authors.affiliation: Monash Institute of Pharmaceutical Sciences, Monash University , Parkville, VIC 3052, Australia.
authors.forename: Roger J
authors.initials: RJ
authors.lastname: Summers
authors.affiliation: Takeda Cambridge Ltd. , Cambridge CB4 0PZ, United Kingdom.
authors.forename: Johannes
authors.initials: J
authors.lastname: Grosse
authors.forename: John D
authors.initials: JD
authors.lastname: Wade
authors.forename: Ross A D
authors.initials: RA
authors.lastname: Bathgate
authors.forename: Mohammed Akhter
authors.initials: MA
authors.lastname: Hossain
mesh_terms: D000818:Animals; D016466:CHO Cells; D003412:Cricetulus; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007328:Insulin / Q000819:agonists*; D051379:Mice; D008958:Models, Molecular; D015394:Molecular Structure; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D015202:Protein Engineering; D011506:Proteins / Q000819:agonists*; D013329:Structure-Activity Relationship
chemical_list: D007328:Insulin; C084797:Leydig insulin-like protein; D010455:Peptides; D011506:Proteins