对约氏疟原虫不同易感性的大劣按蚊和斯氏按蚊基因组RAPD序列比较

RAPD Analysis of Anopheles dirus and Anopheles stephensi

目的分析对约氏疟原虫不易感的大劣按蚊和易感的斯氏按蚊基因组RAPD谱带并测序,探讨媒介按蚊基因型与疟原虫基因型间的相互关系。方法用已筛选的一条随机引物,随机扩增大劣按蚊和斯氏按蚊成蚊的基因组DNA,扩增产物经琼脂糖凝胶电泳后,对相同迁移率的DNA条带克隆、测序,并采用相关在线程序及软件进行序列比较分析。结果大劣按蚊和斯氏按蚊RAPD谱带具有明显的种间差异,但有4对相同迁移率的条带。序列分析显示4对DNA条带在序列长度和组成上呈现多态性,序列的GC含量和简单重复序列存在差异,序列相似性介于48%～52%之间。结论大劣按蚊和斯氏按蚊之间存在不同的遗传背景,其基因多态性可能与产生对约氏疟原虫的易感性不同有关,为进一步研究按蚊与疟原虫之间的相互作用奠定了基础。

Objective To analyze the randomly amplified polymorphic DNA （RAPD） bands of Anopheles dirus and A.stephensi,and the relationship between the host genotype the susceptibility of anopheline mosquitoes to Plasmodium yoelii. Method The genomic DNA extracted from the adults of A.dirus and A.stephensi were amplified by RAPD, and then the amplified products were separated by agarose gel electrophoresis. The gel-purlfied RAPD bands which have similar mobility were isolated and sequenced. Sequence alignment was performed by using DNASIS program. Result The genomic DNA of A.dirus and A.stephensi were successfully amplified by RAPD, and there was obvious difference in their finger printings of the genomic DNA. Sequence alignment of four pairs of RAPD bands which have similar mobility between different anopheline mosquitoes showed that each pair of RAPD bands were differed in GC content and Simple Sequence Repeat, and their similarities were in the arrange from 48% to 52%. It is demonstrated that there are polymorphism in the length and sequences of RAPD bands which have similar mobility. Conclusion Our results indicated that gene variance was distinguished between A.dirus and A.stephensi, and the compatibility between Plasmodium yoelii and mosquito host appear to be, at least in part, determined by the different genetic background of A .dirus and A.stephensi. These findings are useful for the further studies on the interactions between anopheline mosquitoes host and plasmodium genotypes.