四种草履虫基因组多态性的研究

A RAPD Study on the Genome DNA in Four Species of -Paramecium

:用 2 0种随机引物对多小核草履虫、旋毛草履虫、双小核草履虫和绿草履虫四种纤毛虫基因组多态性分析显示 ,多小核草履虫与双小核草履虫有共有片段 2 7条 ,共享度达 45 .8% ;旋毛草履虫和绿草履虫有共有片段 2 7条 ,共享度为 42 .8%。多小核草履虫与旋毛草履和绿草履虫的共有片段分别为 1 0条和 1 1条 ,共享度分别为 1 7.1 %和 1 6 .8%。双小核草履虫与旋毛草履虫和绿草履虫的共有片段分别为 1 2条和 1 9条 ,共享度分别为 2 1 .2 %和 2 9.9%。所得结果与Woodruff和Wichterman对草履虫属的两类群的假设相一致。据此作者推测 ,同属于一个类群的草履虫 ,即多小核草履虫和双小核草履虫、旋毛草履虫和绿草履虫的亲缘关系较近。

Genetic variation of four species of Paramecium , such as Paramecium multimicronucleatum, P.aurelia, P.trichium and P.bursaria , was detected by RAPD. The results showed that P.multimicronucleatum shared 27 common fragments with P.aurelia , and the band sharing coefficient is 45.8%, and that P. trichium shared 27 common fragments with P.bursaria , and the band-sharing coefficient is 42.8%, and that P.multimicronucleatum and P. trichium shared 10 common fragments, and P.multimicronucleatum and P.multimicronucleatum and P.bursaria shared 11 fragments, and their bandsharing coefficient are respectively 17.1% and 16.8%, and that P.aurelia shared 12 and 19 common fragments respectively with P. trichium and P.bursaria . So it can be assumed that relationship between species in the same category of paramecium is even closer than that in the different category. The findings are consistent with Woodruff and Wichterman's hypothesis that paramecium can be divided into two categories, namely aurelia and bursaria. RAPD may be valuable to research of systematics of the ciliate.