青海湖裸鲤舌状绦虫裂头蚴的分子鉴定及系统发育研究

通过PCR方法扩增了青海湖裸鲤体腔寄生舌状绦虫18S rRNA、COⅠ和COB基因部分序列, 并进行分子鉴定, 分析了3种基因的同源性, 利用这3种基因进行分子进化和系统发育研究。结果显示, 经过分子鉴定, “面条样”绦虫为肠舌状绦虫, 克隆的18S rRNA、COⅠ和COB基因序列分别与AF254121(中国)、AF153910(中国)和JQ279109(阿尔及利亚)的核苷酸序列同源性为100.00%、99.49%和93.32%。同时, 利用GenBank中其他种属绦虫的18S rRNA、COⅠ和COB基因序列构建系统发育树, 均与已鉴定的肠舌状绦虫聚在同一支上, 且与肠舌状绦虫中国广州分离株种属亲缘关系较近, 与其他绦虫所属分支相距较远。初步阐明了鉴定的肠舌状绦虫分离株与其他种属之间的系统发育关系。

MOLECULAR IDENTIFICATION AND PHYLOGENETIC STUDY OF LIGULA INTESTINALIS PLEROCEROID IN GYMNOCYPRIS PRZEWALSKII FROM THE QINGHAI LAKE,CHINA

To identify Ligula intestinalis pleroceroid parasitizing in the abdominal cavity of Gymnocypris przewalskii and analyze its phylogenic status from Qinghai Lake, China, polymerase chain reaction (PCR) of 18S ribosomal RNA gene, COⅠand COB gene was carried out. Their sequences homologies with other tapeworm species were analyzed and the phylogenetic relationships were inferred. The results showed that the noodle-like parasite was identified as L. intestinalis, and that its 18S rRNA gene homogeneity was 100.00% with AF254121 (China), and COⅠand COB gene homogeneities were 99.49% and 93.32% with AF153910 (China) and JQ279109 (Algeria), respectively. Furthermore, the phylogenetic trees based on the 18S rRNA, COⅠand COB gene sequences indicated that the collected tapeworm was in the same branch with L. intestinalis, which are close to the isolated species from China. The phylogenetic relationship between the identified L. intestinalis and other tapeworm species was elucidated.