Egyed Z, Sréter T, Széll Z, Nyiro G, Márialigeti K, Varga I
Department of Immunology and Molecular Biology, Central Veterinary Institute, Budapest, Hungary.
Vet Parasitol. 2002 Sep 10;108(2):153-61. doi: 10.1016/s0304-4017(02)00186-3.
The morphology of Onchocerca lupi, responsible for canine ocular onchocercosis, is unique within the genus. Earlier analyses of the 5S ribosomal RNA gene spacer region sequence of the parasite and the 16S ribosomal RNA gene sequence of its Wolbachia endosymbiotic bacteria (Rickettsiales) supported the morphological and biological arguments that O. lupi is a distinct species. However, the exact phylogenetic position of O. lupi and its endosymbiont could not be unambiguously determined. Herein we report analyses based on the mitochondrial cytochrome oxidase I (COI) gene of the filarial species and the Wolbachia surface protein (wsp) and the bacterial cell-cycle ftsZ genes of their wolbachiae. Our results indicate that O. lupi separated from other Onchocerca spp. early in evolution. This is in line with the previous morphological analysis demonstrating that O. lupi is an atypical Onchocerca species showing both primitive and evolved characters. The phylogenetic trees generated for the COI sequences of filariae and the wsp and ftsZ sequences of their wolbachiae were congruent with each other, which supports the hypothesis that nematodes and their Wolbachia endobacteria share a long co-evolutionary history.
导致犬眼盘尾丝虫病的盘尾丝虫（Onchocerca lupi）的形态在该属内是独特的。对该寄生虫的5S核糖体RNA基因间隔区序列及其沃尔巴克氏体共生细菌（立克次氏体目）的16S核糖体RNA基因序列的早期分析支持了形态学和生物学观点，即盘尾丝虫是一个独特的物种。然而，盘尾丝虫及其内共生体的确切系统发育位置无法明确确定。在此，我们报告基于丝虫物种的线粒体细胞色素氧化酶I（COI）基因以及其沃尔巴克氏体的沃尔巴克氏体表面蛋白（wsp）和细菌细胞周期ftsZ基因的分析。我们的结果表明，盘尾丝虫在进化早期就与其他盘尾丝虫属物种分离。这与之前的形态学分析一致，该分析表明盘尾丝虫是一种非典型的盘尾丝虫物种，兼具原始和进化特征。为丝虫的COI序列以及其沃尔巴克氏体的wsp和ftsZ序列生成的系统发育树相互一致，这支持了线虫及其沃尔巴克氏体内生细菌有着长期共同进化历史的假设。
