牛瑟氏泰勒虫吉林株18S rRNA基因的扩增及系统发育研究

本研究根据GenBank上发表的牛瑟氏泰勒虫18S rRNA基因的核苷酸序列设计并合成1对特异性引物,对寄生于牛体内的瑟氏泰勒虫基因组DNA进行扩增,得到1 356 bp的18S rRNA基因片段,测序后blast分析表明该虫种属牛瑟氏泰勒虫。将该基因片段序列与GenBank中8种已知泰勒虫的相应序列进行比较分析,建立系统发育树。结果表明,牛瑟氏泰勒虫吉林分离株与水牛泰勒虫亲缘关系最近,与小泰勒虫亲缘关系较远。这一结果说明宿主因素对泰勒虫的基因型影响较大。

Amplification of 18S rRNA gene from Jilin strain of cattle Theileria sergenti and its phylogenesis analysis

A pair of primers was designed according to Theileria sergenti 18S rRNA gene sequences published in the GenBank.The 18S rRNA gene fragment was amplified by PCR and sequenced.The results showed that the gene was 1 356 bp in length and confirmed that it was from T.sergenti.The complete gene sequence was compared with those of 8 other Theileria strains available in GenBank.The phylogenetic tree indicated that Jilin strain of cattle T.sergenti was closer to T.buffeli,but the distant was far to T.parva.It suggested that host factors have a larger impact on the genetic of Theileria.