基于wsp基因的叶螨体内Wolbachia株系的多样性与重组分析

Diversity and recombination of Wolbachia strains in spider mites based on analysis of the wsp gene

胞内共生菌Wolbachia能对多种叶螨产生生殖调控作用。为更好地筛选有潜在应用价值的Wolbachia株系,本研究应用PCR技术对自然种群的截形叶螨Tetranychus truncatus、二斑叶螨T.urticae、神泽叶螨T.kanzawai和山楂叶螨Amphitetranychus viennensis体内的Wolbachia感染情况进行检测,并对Wolbachia的wsp基因进行序列分析和基因重组检测。结果表明,叶螨中的Wolbachia株系具有较高的遗传多样性,其中截形叶螨感染两种分化较大的株系。不同叶螨感染特有的Wolbachia株系说明Wolbachia与其宿主存在一定的协同进化关系。二斑叶螨和截形叶螨感染同一株系的Wolbachia,可能由于水平传播造成。同时,不同株系Wolbachia的wsp基因间普遍存在着基因重组现象。

Wolbachia are intracelIular bacteria with the ability to manipulate the reproduction of several spider mite species. We used PCR to examine the infection status of four spider mite species （ Tetranychus truncatus, T. urticae, T. kanzawai and Amphitetranychus viennensis） from different wild populations in China. The sequences and recombination of the wsp gene were then analyzed in order to obtain potentially useful Wolbachia strains. The results indicate that there is a high level of Wolbachia diversity in spider mites; for example, two divergent strains were observed in T. truncatus. Distinctive strains of Wolbachia were each only found in a single species of spider mite, suggesting the potential co- divergence of Wolbachia strains with their hosts. One instance of T. truncatus and T. urticae being infected with an identical Wolbachia strain might have been caused by horizontal transmission. Evidence of recombination of the wsp gene was also discovered.