title: Neuropeptides encoded by the genomes of the Akoya pearl oyster Pinctata fucata and Pacific oyster Crassostrea gigas: a bioinformatic and peptidomic survey.
abstract: BACKGROUND
  Oysters impart significant socio-ecological benefits from primary production of food supply, to estuarine ecosystems via reduction of water column nutrients, plankton and seston biomass. Little though is known at the molecular level of what genes are responsible for how oysters reproduce, filter nutrients, survive stressful physiological events and form reef communities. Neuropeptides represent a diverse class of chemical messengers, instrumental in orchestrating these complex physiological events in other species.
  
  
  RESULTS
  By a combination of in silico data mining and peptide analysis of ganglia, 74 putative neuropeptide genes were identified from genome and transcriptome databases of the Akoya pearl oyster, Pinctata fucata and the Pacific oyster, Crassostrea gigas, encoding precursors for over 300 predicted bioactive peptide products, including three newly identified neuropeptide precursors PFGx8amide, RxIamide and Wx3Yamide. Our findings also include a gene for the gonadotropin-releasing hormone (GnRH) and two egg-laying hormones (ELH) which were identified from both oysters. Multiple sequence alignments and phylogenetic analysis supports similar global organization of these mature peptides. Computer-based peptide modeling of the molecular tertiary structures of ELH highlights the structural homologies within ELH family, which may facilitate ELH activity leading to the release of gametes.
  
  
  CONCLUSIONS
  Our analysis demonstrates that oysters possess conserved molluscan neuropeptide domains and overall precursor organization whilst highlighting many previously unrecognized bivalve idiosyncrasies. This genomic analysis provides a solid foundation from which further studies aimed at the functional characterization of these molluscan neuropeptides can be conducted to further stimulate advances in understanding the ecology and cultivation of oysters.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Stewart
authors.forename: Pascal
authors.initials: P
authors.lastname: Favrel
authors.forename: Bronwyn A
authors.initials: BA
authors.lastname: Rotgans
authors.forename: Tianfang
authors.initials: T
authors.lastname: Wang
authors.forename: Min
authors.initials: M
authors.lastname: Zhao
authors.forename: Manzar
authors.initials: M
authors.lastname: Sohail
authors.forename: Wayne A
authors.initials: WA
authors.lastname: O'Connor
authors.forename: Abigail
authors.initials: A
authors.lastname: Elizur
authors.forename: Joel
authors.initials: J
authors.lastname: Henry
authors.affiliation: School of Science and Education, Genecology Research Center, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia. scummins@usc.edu.au.
authors.forename: Scott F
authors.initials: SF
authors.lastname: Cummins
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D049896:Crassostrea / Q000235:genetics*; D057225:Data Mining; D016678:Genome / Q000235:genetics; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000737:chemistry / Q000235:genetics*; D049911:Pinctada / Q000235:genetics* / Q000378:metabolism; D040901:Proteomics
chemical_list: D009479:Neuropeptides