title: Identification of a female spawn-associated Kazal-type inhibitor from the tropical abalone Haliotis asinina.
abstract: Abalone (Haliotis) undergoes a period of reproductive maturation, followed by the synchronous release of gametes, called broadcast spawning. Field and laboratory studies have shown that the tropical species Haliotis asinina undergoes a two-week spawning cycle, thus providing an excellent opportunity to investigate the presence of endogenous spawning-associated peptides. In female H. asinina, we have isolated a peptide (5145 Da) whose relative abundance in hemolymph increases substantially just prior to spawning and is still detected using reverse-phase high-performance liquid chromatography chromatograms up to 1-day post-spawn. We have isolated this peptide from female hemolymph as well as samples prepared from the gravid female gonad, and demonstrated through comparative sequence analysis that it contains features characteristic of Kazal-type proteinase inhibitors (KPIs). Has-KPI is expressed specifically within the gonad of adult females. A recombinant Has-KPI was generated using a yeast expression system. The recombinant Has-KPI does not induce premature spawning of female H. asinina when administered intramuscularly. However it displays homomeric aggregations and interaction with at least one mollusc-type neuropeptide (LRDFVamide), suggesting a role for it in regulating neuropeptide endocrine communication. This research provides new understanding of a peptide that can regulate reproductive processes in female abalone, which has the potential to lead to the development of greater control over abalone spawning. The findings also highlight the need to further explore abalone reproduction to clearly define a role for novel spawning-associated peptide in sexual maturation and spawning. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.
authors.affiliation: Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore, QLD, 4558, Australia.
authors.forename: Tianfang
authors.initials: T
authors.lastname: Wang
authors.affiliation: Faculty of Allied Health Sciences, Burapha University, Chonburi, 20131, Thailand.
authors.forename: Parinyaporn
authors.initials: P
authors.lastname: Nuurai
authors.affiliation: School of Biological Sciences, The University of Queensland, St Lucia, QLD, 4072, Australia.
authors.forename: Carmel
authors.initials: C
authors.lastname: McDougall
authors.affiliation: School of Biological Sciences, The University of Queensland, St Lucia, QLD, 4072, Australia.
authors.forename: Patrick S
authors.initials: PS
authors.lastname: York
authors.affiliation: Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore, QLD, 4558, Australia.
authors.forename: Utpal
authors.initials: U
authors.lastname: Bose
authors.affiliation: School of Biological Sciences, The University of Queensland, St Lucia, QLD, 4072, Australia.
authors.forename: Bernard M
authors.initials: BM
authors.lastname: Degnan
authors.affiliation: Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore, QLD, 4558, Australia.
authors.forename: Scott F
authors.initials: SF
authors.lastname: Cummins
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006458:Hemolymph / Q000737:chemistry; D008958:Models, Molecular; D008974:Mollusca / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D009479:Neuropeptides / Q000235:genetics / Q000378:metabolism*; D010053:Ovary / Q000254:growth & development / Q000378:metabolism*; D010843:Pichia / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012098:Reproduction / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012741:Sexual Maturation / Q000235:genetics*; D015398:Signal Transduction; D014359:Trypsin Inhibitor, Kazal Pancreatic / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D009479:Neuropeptides; D011994:Recombinant Proteins; D014359:Trypsin Inhibitor, Kazal Pancreatic
keywords: abalone; hemolymph; ovary; protease inhibitor; reproduction; spawning