革胡子鲶生长激素cDNA克隆与蛋白质结构分析  

cDNA cloning and protein structure analysis of growth hormone from Clarias lazera

作　　者：杨学明[1] 何荆洲[1] 黄雄军[1] 李芳芳[1] 郭亚芬[1] 蒋和生[1] 

机构地区：[1]广西大学动物科技学院

出　　处：《遗传》2008年第7期913-918,共6页Hereditas（Beijing)

基　　金：广西自然科学基金项目(编号:桂科自0542035)资助~~

摘　　要：从革胡子鲶(Clarias lazera(Burchell))的脑垂体组织中提取总RNA,应用RT-PCR方法,扩增得到了革胡子鲶生长激素(Growth hormone,GH)基因cDNA的开放阅读框(Open reading frame,ORF)序列。ORF全长为603nt,编码由22个信号肽氨基酸和178个成熟肽氨基酸共同组成的生长激素前体蛋白。序列同源比较结果表明,研究中得到的革胡子鲶生长激素氨基酸序列与GenBank中已报道的其他6种鲶形目鱼类的氨基酸序列同源性高达95.8%。二级结构预测分析结果表明,革胡子鲶生长激素蛋白中含有α螺旋、β折叠和β转角以及无规卷曲等二级结构,以α螺旋为主,是典型的α型结构蛋白质。此外,抗原性分析表明,在氨基酸序列中的4个区域均可形成优势抗原表位,其结构特点非常适合改造成为重组生长激素疫苗或单克隆抗体制剂加以开发利用。Total RNA was isolated from pituitary gland of Clarias lazera, and the cDNA encoding growth hormone （GH） protein was amplified and cloned by reverse transcription polymerase chain reaction（RT-PCR）. The open reading frame （ORF） of cDNA is of 603 nt which encodes GH precursor consisted of a signal peptide with 22 amino acid residues and a mature peptide with 178 amino acid residues. Sequence alignment indicated that the amino acid sequence homology approached to 95.8% between C. lazera and other 6 species of Siluriforms catfish. Secondary structure assessment showd that the GH protein containd different structural regions of or-helix, β-sheet, β-turn and random coil, among which or-helix has main proportion. Antigenicity analysis indicates that there exist 4 domains in amino acid sequence where B cell dominant epitopes could form. Summarily, the structure characteristics of C. lazera GH should provide a great benefit in its modification into recombinant vaccine or monoclonal antibody for future application.

关 键 词：革胡子鲶 生长激素 CDNA克隆 二级结构 

分 类 号：Q78[生物学—分子生物学] S917.4[农业科学—水产科学]