【摘要】 【目的】获得细粒棘球蚴抗原B亚单位基因序列 ,并进行序列分析。【方法】从包虫病羊体内获取细粒棘球蚴原头节 ,使用TRIZOL试剂提取总RNA ,逆转录成cDNA。根据E .granulosus抗原B亚单位基因的已知序列设计一对引物 ,采用RT PCR技术扩增出抗原B亚单位基因 ;将PCR产物纯化后用双脱氧链末端终止法进行序列测定 ,并进行序列分析。【结果】用RT PCR成功扩增出细粒棘球蚴抗原B亚单位基因序列 ,测序表明该基因ORF为 2 70bp ,和已发表基因核苷酸序列相比 ,缺失 3个碱基 ,同源性为 84 2 % ,推导编码氨基酸序列同源性为 77 8%。【结论】从E .granulosuscDNA扩增出抗原B亚单位基因 ,该基因编码 8ku亚单位前体蛋白。更多还原

【Abstract】 Objective To obtain and analyze the sequence of cDNA of Echinococcus granulosus antigen B subunit gene. Method Total RNA was extracted from protoscoles of cysts from ovine origin by using TRI ZOL Reagents. The specific primers were designed according to published nucleotide sequence in the GenBank database. The Echinococcus granulosus cDNA was amplified by RT-PCR. The purified product of PCR was sequenced by the dideoxy chain termination method, and sequence analyses was performed by using standard computer program. Results A cDNA sequence with an open reading frame of 270 bp has been amplified successfully by using RT-PCR. Comparison of the DNA sequence and amino acid sequence deduced from cDNA with the published 8 ku subunit sequence of Echinococcus granulosus antigen B in the GenBank revealed lack of three bases and 84.27% and 77.8% identity respectively. Conclusion Ag B subunit gene has been isolated from cDNA of E.granulosus, this gene encodes a 8 ku subunit precursory protein.更多还原