内源性绵羊肺腺瘤病毒NM株gag基因的克隆、序列分析及蛋白结构预测

Cloning and sequence analysis of the gag gene of endogenous jaagsiekte sheep retrovirus inner mongolia strain

提取内源性绵羊肺腺瘤病毒内蒙古分离株(NM)总DNA,参照GenBank中内源性绵羊肺腺瘤病毒enJS56A1株gag基因序列设计1对引物。应用PCR技术特异性地扩增出病毒的gag基因片段,将其克隆到pMD19-T载体中进行测序得到完整的gag基因序列,并用DNAStar软件进行序列分析,分析结果表明,与内源性南非代表毒株enJS56A1(AF153615)的gag基因序列比较,核苷酸同源性为98.9%。推导出的氨基酸同源性为98.4%。与外源性美国代表株JSRV21(AF105220)的gag基因序列比较,核苷酸同源性为89.6%,氨基酸同源性为94.8%。利用生物信息学软件对其蛋白结构进行预测,结果表明gag-enJSRV-NM为一结构松散的蛋白分子,这也是我国首次报道的内源性绵羊肺腺瘤病毒的gag基因的全序列,为我国科研工作者进行更深入的研究奠定了基础。

A gag gene was amplified from endogenous jaagsiekte sheep retrovirus NM strain （enJSRV-NM） isolated in Inner Mongolia by PCR using a pair of primers designed according to the published gag gene sequence of enJS56AI strain. The PCR product was cloned into pMD19-T vector and then sequenced, The nucleotide and amino acid sequences of NM strain gag gene were compared with those of South Africa enJS56Al strain （AF153615） and USA JSRV21 strain （AF105220） using DNAStar softwaxe. The nucleotide and amino acid homology of gag gene were 98.9 %, 98.4 % and 89.6 %, 94.8 %, respectively, This is the first nucleotide sequence of enJSRV reported in China, The protein structure prediction showed that the gag-enJSRV-NM protein has a relatively loose structure.