裳卷蛾变形孢虫SSU rRNA核心序列的克隆与系统发育分析

[目的]利用分子生物学手段探索裳卷蛾变形孢虫的遗传发育地位.[方法]微孢子虫的SSUrRNA序列是构建系统发育进化树的重要工具.试验通过T-A克隆法对裳卷蛾变形孢虫(Vairimorphaceraces)SSU rRNA核心序列进行了克隆,并采用近邻法构建了系统发育进化树.[结果]克隆得到了长为1228bp的核苷酸序列(GenBank EU267796).系统发育分析结果表明:裳卷蛾变形孢虫与分离于小菜蛾(Plutella xylostella)的Vairimorpha sp.Germany(GenBank AF124331)和Vairimorphaimperyecta(GenBank AJ131645)相似性最高,它们在系统发育进化树中与寄主为鳞翅目昆虫的Nosema属聚为一类,与纳卡变形孢虫(Vairimorpha necatrix)为代表的Vairimorpha属为相邻集.[结论]结合其生物学特征,裳卷蛾变形孢虫确实为Vairimorph a属的成员,但根据系统发育分析归入Nosematidae科可能更为合适.

Cloning and phylogenetic analysis of small subunit ribosomal RNA core sequence of Vairimorpha ceraces (Microspora: Burenellidae) from the insect of Lepidoptera, Cerace stipatana (Walker)

Abstract: [Objective] Vairimorpha ceraces is a new microsporidium that isolated from the insect of Lepidoptera, Cerace Stipatana (Walker). We used 16S rDNA sequence to explore genetic status of Vairimorpha ceraces. [Methods] SSU rDNA (small subunit ribosomal RNA) of Vairimorpha ceraces was cloned and sequenced for constructing phylogenetic tree through Neighbor-joining. [Results] The core sequence of SSU rRNA of Vairimorpha ceraces with a length of 1228 nucleotides (GenBank EU267796) was successfully cloned and sequenced. Phylogenetic analysis showed that Vairimor-pha ceraces was closer to the species of Vairimorpha sp. Germany (GenBank AF124331) and Vairimorpha imperfecta (GenBank AJ131645), both isolated from Plutella xylostella. The three species of genera Vairimorpha included Vairi-morpha ceraces formed a clade with the Nosema spp. which from Lepidoptera host in phylogenetic tree. Conversely, other three Vairimorpha spp. from Lepidoptera (Vairimorpha necatrix, Vairimorpha sp. NISM12 and Vairimorpha lymantriae) were mixed with Nosema spp. from non-lepidopteran host in the other clade. [Conclusion] Combined with the biological characters, Vairimorpha ceraces was a member of genera Vairimorpha, Family Nosematidae.