文蛤胞内铜锌超氧化物歧化酶基因的克隆与序列分析  

Molecular Cloning and Sequence Analysis of an Intracellular Cu/Zn-superoxide Dismutase Gene from Hard Clam(Meretrix meretrix)

作　　者：朱丹[1,2] 李宏俊[2] 高祥刚[2] 苏浩[2] 赫崇波[2] 

机构地区：[1]辽宁师范大学生命科学学院,大连116029 [2]辽宁省海洋水产科学研究院辽宁省海洋水产分子生物学重点实验室,大连116023

出　　处：《生物技术通报》2010年第11期123-128,133,共7页Biotechnology Bulletin

基　　金：辽宁省科学技术计划重大;重点项目(2008203001);辽宁省海洋与渔业科研计划项目(200801);国家海洋公益性行业科技专项(200805037)

摘　　要：文蛤(Meretrix meretrix)是我国重要的滩涂养殖贝类之一,由于病害等原因,特别是红肉病的蔓延,文蛤增养殖业的发展受到严重制约。铜锌超氧化物歧化酶(Cu/Zn-SOD)是活性氧清除酶系中最重要的酶,在生物体内参与清除氧自由基,防御分子损伤和机体衰老等诸多生物事件。通过构建SMART全长cDNA文库和RACE的方法,克隆得到了文蛤胞内Cu/Zn-SOD(icCu/Zn-SOD)的全长cDNA序列。生物学软件分析表明,该序列全长为1383bp,5′UTR为45bp,3′UTR为876bp,开放阅读框长度为462bp,编码153个氨基酸,Cu原子分别与His46、His48、His63、His119配位,Zn则与His63、His71、His80和Asp83配位,半胱氨酸Cys57和Cys145之间形成唯一的链内二硫键。蛋白质结构中心是由8条反向平行的β折叠围成的圆桶状结构。文蛤icCu/Zn-SOD与紫贻贝等其它9种海洋贝类的Cu/Zn-SOD具有较高的同源性。Meretrix meretrix is one of China＇s important economic,widely distributed in East Asia along the coast.Species superoxide dismutases are an ubiquitous family of enzymes that function to efficiently catalyze the dismutation of superoxide anions.In the present study,the intracellular Cu/Zn-SOD gene（icCu/Zn-SOD）of Meretrix meretrix（denoted as Mm-Cu/Zn-SOD）was obtained through constructing SMART cDNA library and RACR approaches.The full-length cDNA of Mm-CuZnSOD was 1 383 bp with a 462 bp open reading frame encoding 153 amino acids.The deduced amino acid of Mm-Cu/Zn-SOD shared high similarity with the icCu/Zn-SODs from other species,indicating that Mm-Cu/Zn-SOD should be a new member of icCu/Zn-SOD family.Several highly conserved motifs including Cu,Zn binding sites（H（46）,H（48）,H（63）,H（119）for Cu binding,and H（63）,H（71）,H（80）,D（83）for Zn binding）,intracellular disulfide bond and two Cu,Zn SOD signatures were also identified in Mm-Cu/Zn-SOD.Through tertiary structure prediction,main spatial structure of protein is β-barrel.The Cu/Zn-SOD in Meretrix meretrix is highly homologous to Cu/Zn-SOD in Crassostrea ariakensis and other nine shellfish.

关 键 词：文蛤 铜锌超氧化物歧化酶 表达序列标签 CDNA文库 

分 类 号：S917.4[农业科学—水产科学]