云南香格里拉的带绦虫rDNA-ITS1序列测定及分析

Detection and analysis on the sequence of internal transcribed space-1 in ribosomal DNA of Taenia cestodes from Xiangelila of Yunnan province

目的利用分子生物学技术鉴定产于云南香格里拉带绦虫的种类,以明确当地是否存在亚洲带绦虫。方法从云南香格里拉采集带绦虫标本株成虫节片,抽提DNA,PCR扩增rDNA-ITS1区段,克隆此片段后做序列测定;结合GenBank中已知的亚洲带绦虫、牛带绦虫、猪带绦虫rDNA-ITS1序列,经DNAMAN软件处理后计算遗传距离并构建系统发育树状图。结果香格里拉的带绦虫标本与GenBank中已知的亚洲带绦虫序列同源性为99%;与牛带绦虫同源性98%;与猪带绦虫同源性92%。系统发育树显示:香格里拉标本与亚洲带绦虫标本遗传距离最近,距牛带绦虫标本较远,与猪带绦虫则更远。结论云南香格里拉存在亚洲带绦虫。

By means of the molecular biological technique, the Taenia cestodes in Xianggelila of Yunnan province was investigated in order to determine whether Taenia asiatica exists in this area. The genomic DNA of T. cestodes was extracted from segment adult tapeworms in this area, and the internal transcribed space-1 （ITS1） in ribosomal DNA（rDNA-ITS1） gene sequences were amplified by PCR, cloned and then sequenced. The genomic distance and phylogenetic tree of strain in Xianggelila were constructed in comparison with other known rDNA-ITS-1 gene sequences of Taenia asiatica. T. saginata and T. solium in GenBank using DNAMAN software. It was found that the homologies of the rDNA-ITS1 gene sequence of T. cestodes from Xianggelila between those of the known T. asiatica, T. saginata and T solium in GenBank were 99%, 98% and 92 % respectively. From the analysis of the phylogenetic tree constructed, it revealed that Xianggelila strain was close to T. asiatica genetically, but it was far from T. saginata, and even farther from T. solium. It is concluded that T. asiatica exists in Xianggelila of Yunnan province.