title: Characterization and expression of calmodulin gene during larval settlement and metamorphosis of the polychaete Hydroides elegans.
abstract: The polychaete Hydroides elegans (Serpulidae, Lophotrochozoa) is a problematic marine fouling organism in most tropical and subtropical coastal environment. Competent larvae of H. elegans undergo the transition from the swimming larval stage to the sessile juvenile stage with substantial morphological, physiological, and behavior changes. This transition is often referred to as larval settlement and metamorphosis. In this study, we examined the possible involvement of calmodulin (CaM) - a multifunctional calcium metabolism regulator, in the larval settlement and metamorphosis of H. elegans. A full-length CaM cDNA was successfully cloned from H. elegans (He-CaM) and it contained an open reading frame of 450 bp, encoding 149 amino acid residues. It was highly expressed in 12h post-metamorphic juveniles, and remained high in adults. In situ hybridization conducted in competent larvae and juveniles revealed that He-CaM gene was continuously expressed in the putative growth zones, branchial rudiments, and collar region, suggesting that He-CaM might be involved in tissue differentiation and development. Our subsequent bioassay revealed that the CaM inhibitor W7 could effectively inhibit larval settlement and metamorphosis, and cause some morphological defects of unsettled larvae. In conclusion, our results revealed that CaM has important functions in the larval settlement and metamorphosis of H. elegans.
authors.affiliation: KAUST Global Collaborative Research Program, Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China.
authors.forename: Zhang-Fan
authors.initials: ZF
authors.lastname: Chen
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.forename: Pei-Yuan
authors.initials: PY
authors.lastname: Qian
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002147:Calmodulin / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D017124:Conserved Sequence; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental; D007814:Larva / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D008675:Metamorphosis, Biological; D008969:Molecular Sequence Data; D010802:Phylogeny; D011077:Polychaeta / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D017434:Protein Structure, Tertiary; D013449:Sulfonamides / Q000494:pharmacology
chemical_list: D002147:Calmodulin; D013449:Sulfonamides; C017967:W 7