title: A novel matrix protein family participating in the prismatic layer framework formation of pearl oyster, Pinctada fucata.
abstract: Understanding the molecular composition and the formation mechanism of shell matrix framework is of great interest for biomineralization in mollusk shell. The cDNAs encoding a novel matrix protein family (KRMP) were cloned from the mantle of pearl oyster, Pinctada fucata. Analysis of the deduced amino acid sequences revealed that KRMP have a high proportion of lysine, glycine, and tyrosine, and their predict isoelectric points are higher than any other identified shell matrix protein to our knowledge. The deduced amino acid sequences of KRMP can be divided into three regions, including an N-terminal signal peptide, a lysine-rich basic region interacting with acidic proteins or CO(3)(2-), and a Gly/Tyr-rich region involved in the protein cross-link via quinone-tanning process. RT-PCR and in situ hybridization demonstrated that KRMP mRNA was specifically expressed in the mantle edge, involved in the prismatic layer formation. Taken together, it seems that KRMP is a matrix protein family participating in the framework formation of prismatic layer.
authors.affiliation: Institute of Marine Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, China.
authors.forename: Cen
authors.initials: C
authors.lastname: Zhang
authors.forename: Liping
authors.initials: L
authors.lastname: Xie
authors.forename: Jing
authors.initials: J
authors.lastname: Huang
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Liu
authors.forename: Rongqing
authors.initials: R
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016326:Extracellular Matrix Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D049911:Pinctada / Q000378:metabolism* / Q000648:ultrastructure*
chemical_list: D016326:Extracellular Matrix Proteins