海湾扇贝(Argopecten irradians)金属硫蛋白基因的克隆与分析
CLONING AND CHARACTERIZATION OF A METALLOTHIONEIN GENE IN BAY SCALLOP ARGOPECTEN IRRADIANS

刘维青 ¹ 倪多娇 ¹ 宋林生 ¹ 吴龙涛 ¹ 胥炜 ¹ 孔晓瑜 ²

文摘	金属硫蛋白是一种普遍存在于生物体内的低分子量、半胱氨酸含量丰富、易于被外界刺激诱导的金属结合蛋白。采用表达序列标签法，结合cDNA末端快速扩增技术，首次获得了海湾扇贝金属硫蛋白(AiMT)的全长取cDNA序列。该序列全长787bp,5'UTR(UntranslatedRegion)为79bp，3'UTR为270bp，开放阅读框(Open Reading Frame，ORF)长度为438bp，可编码145个氨基酸。在其编码的氨基酸序列中半胱氨酸含量丰富，甘氨酸含睛也较高，芳香族氨基酸含量低，不合组氨酸，存在有无脊椎动物和软体动物金属硫蛋白的特征序列CKCXXX-CXCX，C-末端的氨基酸序列也符合软体动物金属硫蛋白标签序列C-X-C-x(3)-C-T-G-x(3)-C-x-C-x(3)-C-x-G-K。序列特征分析表明，该序列具备金属蛋白的典型特征，是金属硫蛋白家族的成员。
其他语种文摘	Melallolhioneins( MTs) are linv molecular weighl, cysteine-rifli, mducible metal-binding pro-teins found in a variety of organisms. MTs have many important biological functions acted as a prolective role against excess reactive heavy metal ions, free radical scavengers and reservoir of essential metals that can be donated to other melalloproteins. A partial sequence of the bay scallop Argopecten irradians melullolhionein (named as AiMT) gene was identified from A. irradians cDNA library using expressed sequence tag method. A pair of gene-specific primers was designed according to this sequence and the full-length of AiMT cDNA was obtained using rapid amplificalion of cDNA end technique. The full-length cDNA of AiMT was of 787 lip including a 5'untranslated region (UTR) of 79bp, a 3'UTR of 270 bp and an open reading frame(OHF) of 438bp encoding a polypeplide of 145 ainino acids. The predicted aniino acid sequence of AiMT contained 40 cysleine residues organized in Cys-X_((n))-Cys(n = 1-3) motif as classically described for MTs. The contents of cysleine, glycine and phenylalanine in the AiMT aniino acids sequence were 27.6%, 13.1% and 2.1% respectively while no histidine residue was found. The CKCXXXCXCX motif, a conserved feature for invertebrate and mollusean MT, was found in two regions of the AiMT. A specific pattern of moilusca MT C-X-C-x(3)-C-T-G-x(3)-C-x-C-x(3)-C-x-G-K located at the C-terminal. The result of sequence analysis indicated that AiMT was the member of me-lallothionein family.
来源	海洋与湖沼 ,2006,37(5):444-449 【核心库】
关键词	海湾扇贝 ; 金属硫蛋白基因 ; EST ; cDNA文库
地址	1. 中国科学院海洋研究所, 中国科学院实验海洋生物学重点实验室, 青岛, 266071 2. 中国海洋大学水产学院, 青岛, 266003
语种	中文
文献类型	研究性论文
ISSN	0029-814X
学科	分子生物学
基金	国家863计划 ; 国家自然科学基金
文献收藏号	CSCD:2422943