title: Molecular  characteristics and expression of calmodulin cDNA from the freshwater pearl  mussel, Hyriopsis schlegelii.
abstract: Calmodulin (CaM) is a multifunctional intracellular calcium ion receptor protein that participates in a range of cellular processes, including calcium metabolism in mussels. To investigate the role of CaM in freshwater mollusk shell calcium metabolism, the full-length CaM cDNA was isolated from the freshwater pearl mussel, Hyriopsis schlegelii (referred to as hsCaM) using SMART RACE technology. The full-length hsCaM was 855 bp in size, containing a 70-bp 5'-untranslated sequence, a 447-bp open reading frame, a 309-bp 3'-untranslated sequence, and a 26-nucleotide long poly(A) tail. The hsCaM mRNA expression in different mussel tissues was examined using real-time PCR. The hsCaM mRNA was found to be ubiquitously expressed, but far more abundant in the gill, foot, and mantle than in the posterior adductor muscle. Real-time PCR was also used to determine hsCaM mRNA expression levels in mantle tissues of H. schlegelii at different ages. No significant differences between one-, two-, and three-year-old mussels were detected, but expression increased in four-year-old mussels and then decreased in five-year-old mussels. CaM appears to be involved in calcium regulation of the mantle in four-year-old mussels, which may secrete more mother of pearl during pearl culture.
authors.affiliation: College of Life Science and Food Engineering, Institute of Life Science, Nanchang University, Nanchang, China.
authors.forename: L-G
authors.initials: LG
authors.lastname: Zeng
authors.forename: J-H
authors.initials: JH
authors.lastname: Wang
authors.forename: Y-J
authors.initials: YJ
authors.lastname: Li
authors.forename: J-Q
authors.initials: JQ
authors.lastname: Sheng
authors.forename: Q
authors.initials: Q
authors.lastname: Gu
authors.forename: Y-J
authors.initials: YJ
authors.lastname: Hong
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D049872:Bivalvia / Q000235:genetics*; D002147:Calmodulin / Q000235:genetics* / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA
chemical_list: D002147:Calmodulin; D018076:DNA, Complementary; D012333:RNA, Messenger