title: Identification and Characterization of the Lysine-Rich Matrix Protein Family in Pinctada fucata: Indicative of Roles in Shell Formation.
abstract: Mantle can secret matrix proteins playing key roles in regulating the process of shell formation. The genes encoding lysine-rich matrix proteins (KRMPs) are one of the most highly expressed matrix genes in pearl oysters. However, the expression pattern of KRMPs is limited and the functions of them still remain unknown. In this study, we isolated and identified six new members of lysine-rich matrix proteins, rich in lysine, glycine and tyrosine, and all of them are basic matrix proteins. Combined with four members of the KRMPs previously reported, all these proteins can be divided into three subclasses according to the results of phylogenetic analyses: KRMP1-3 belong to subclass KPI, KRMP4-5 belong to KPII, and KRMP6-10 belong to KPIII. Three subcategories of lysine-rich matrix proteins are highly expressed in the D-phase, the larvae and adult mantle. Lysine-rich matrix proteins are involved in the shell repairing process and associated with the formation of the shell and pearl. What's more, they can cause abnormal shell growth after RNA interference. In detail, KPI subgroup was critical for the beginning formation of the prismatic layer; both KPII and KPIII subgroups participated in the formation of prismatic layer and nacreous layer. Compared with different temperatures and salinity stimulation treatments, the influence of changes in pH on KRMPs gene expression was the greatest. Recombinant KRMP7 significantly inhibited CaCO3precipitation, changed the morphology of calcite, and inhibited the growth of aragonite in vitro. Our results are beneficial to understand the functions of the KRMP genes during shell formation.
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.|State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining, Qinghai Province, 810016, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Liang
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Xie
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Gao
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
authors.forename: Chao-Qun
authors.initials: CQ
authors.lastname: Xu
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Yan
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
authors.forename: Gan-Chu
authors.initials: GC
authors.lastname: Jia
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Xiang
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China. lpxie@mail.tsinghua.edu.cn.|Protein Science Laboratory of the Ministry of Education, Tsinghua University, Beijing, 100084, China. lpxie@mail.tsinghua.edu.cn.
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Xie
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China. rqzhang@mail.tsinghua.edu.cn.|State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining, Qinghai Province, 810016, China. rqzhang@mail.tsinghua.edu.cn.|Protein Science Laboratory of the Ministry of Education, Tsinghua University, Beijing, 100084, China. rqzhang@mail.tsinghua.edu.cn.
authors.forename: Rong-Qing
authors.initials: RQ
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D060105:Animal Shells / Q000254:growth & development / Q000378:metabolism*; D000818:Animals; D002119:Calcium Carbonate / Q000737:chemistry; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D006863:Hydrogen-Ion Concentration; D007814:Larva / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D005810:Multigene Family; D060734:Nacre / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D049911:Pinctada / Q000145:classification / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000378:metabolism; D054712:Salinity; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013696:Temperature
chemical_list: D016326:Extracellular Matrix Proteins; D060734:Nacre; D011994:Recombinant Proteins; D002119:Calcium Carbonate
keywords: Biomineralization; Gene expression; Gene family; KRMP; Mollusk