title: cDNA cloning and in situ hybridization of a novel lysozyme in the Pacific oyster, Crassostrea gigas.
abstract: A novel lysozyme cDNA from the Pacific oyster, Crassostrea gigas, was identified. This second lysozyme from the Pacific oyster was designated as CGL-2. The complete CGL-2 cDNA sequence comprises of 536 bp, and 429 bp of the open reading frame encodes 147 bp of amino acid residues. Estimated CGL-2 molecular characteristics (isoelectric point and numbers of peptide recognition sites) resembled those of cv-lysozyme 2, a digestive lysozyme of the eastern oyster, Crassostrea virginica. Moreover, CGL-2 is phylogenetically homologous to the cv-lysozyme 2, indicating that CGL-2 and cv-lysozyme 2 evolved from the same ancestor protein for adaptation to the digestive environment. In situ hybridization revealed that the CGL-2 gene is expressed in digestive cells. It is noteworthy that the other Pacific oyster lysozyme, CGL-1, was also transcribed in the same cells. Presence and expression of multiple lysozymes in the digestive diverticula suggest that CGL-1 and CGL-2 might play complementary roles in digestive organs.
authors.affiliation: Aquacultural Biology Laboratory, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori Amamiya-machi, Aoba-ku, Sendai, Miyagi 981-8555, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Itoh
authors.forename: Keisuke G
authors.initials: KG
authors.lastname: Takahashi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D049896:Crassostrea / Q000201:enzymology* / Q000235:genetics*; D018076:DNA, Complementary / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009113:Muramidase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D021381:Protein Transport; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: D018076:DNA, Complementary; D009113:Muramidase