title: Identification of chitin in the prismatic layer of the shell and a chitin synthase gene from the Japanese pearl oyster, Pinctada fucata.
abstract: The shell of the Japanese pearl oyster, Pinctada fucata, consists of two layers, the prismatic layer on the outside and the nacreous layer on the inside, both of which comprise calcium carbonate and organic matrices. Previous studies indicate that the nacreous organic matrix of the central layer of the framework surrounding the aragonite tablet is beta-chitin, but it remains unknown whether organic matrices in the prismatic layer contain chitin or not. In the present study, we identified chitin in the prismatic layer of the Japanese pearl oyster, Pinctada fucata, with a combination of Calcofluor White staining with IR and NMR spectral analyses. Furthermore, we cloned a cDNA encoding chitin synthase (PfCHS1) that produces chitin, contributing to the formation of the framework for calcification in the shell.
authors.affiliation: Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Suzuki
authors.forename: Shohei
authors.initials: S
authors.lastname: Sakuda
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Nagasawa
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002686:Chitin / Q000032:analysis / Q000737:chemistry*; D002687:Chitin Synthase / Q000235:genetics*; D008969:Molecular Sequence Data; D049911:Pinctada / Q000737:chemistry* / Q000201:enzymology*
chemical_list: D002686:Chitin; D002687:Chitin Synthase