牙鲆T细胞抗原受体(TCR)β链同源cDNA的克隆  

Cloning of a T Cell Antigen Receptor β-Chain Homolog in Paralichthys olivaceus

作　　者：乌日琴[1] 张培军[1] 李军[1] 徐芃[1] 徐永立[1] 

机构地区：[1]中国科学院海洋研究所实验海洋生物学开放实验室

出　　处：《高技术通讯》2003年第4期85-91,共7页Chinese High Technology Letters

基　　金：973规划(G1999012003;G1999012006)资助项目。

摘　　要：从牙鲆外周血淋巴细胞cDNA文库中克隆TCRβ1319bp同源cDNA序列并对其基因结构进行生物信息学分析。RT-PCR其编码区为942bp,编码314个氨基酸,编码区包括V、D、J和C区4个基因片段。TCRVβ片段主要包括从21～115位氨基酸残基的95个氨基酸序列,Jβ区与哺乳动物的Jβ区高度保守,在位于Vβ和Jβ之间的Dβ区中没有发现8碱基保守序列(GGACAGGG),CDR3β氨基酸序列为GTRILYE。牙鲆TCRCβ片段共有179个氨基酸残基,缺失位于Cβ细胞外区和临近区域的2个5～9氨基酸弹性区域。牙鲆TCRCβ片段的铰链区有6个氨基酸残基,缺少半胱氨酸位点,含Lys271保守位点。经RT-PCR检测,在脾、外周血和前肾中都发现TCRβ的表达,肌肉和肝中均未克隆到目的片段。T cell antigen receptor β-chain cDNA clone were obtained from the Japanese flounder (Paralichthys oliva-ceus) peripheral lymphocytes cDNA library by using RACE (rapid amplification of cDNA end). This cDNA clone, 1319 bp, contains an ORF(open reading frame) of 942bp which encodes a polypeptides of 314 amino acids, including Vβ, Dβ, Jβ and Cβ regions. The deduced amino acids of Vβ region is 95 amino acids residues. The deduced amino acid sequences of CDR3β is GTRILYE. The flounder Cβ is 179 amino acids, the two stretches of five to nine amino acids from the extracellular domain and adjacent region were lost. The putative hinge domain contains 6 amino acides lacking conserved cysteine residue. The flounder Cβ transmembrance-region has the same size as those in other species in which several important residues are rather conserved, including Lys271. RT-PCR analysis revealed that normal expression of TCRβ-chain was highly specific for lymphoid tissues. Expression of TCR p-chain in plant haemoglutinin(PHA)-stimulated lymphocytes from peripheral blood was detected 8 h and 12 h after treatment , we can not detect the expression of TCRβ-chain 16h after PHA-treatment.

关 键 词：牙鲆 T细胞抗原受体β链 TCR-β基因 cDNA末端快速扩增方法 T细胞受体 克隆 鱼类免疫学 疾病治疗 

分 类 号：Q953[生物学—动物学]