基于线粒体基因组序列的异尖科线虫系统发育研究

Accurate identification and differentiation of anisakid nematodes has important implications for the specific diagnosis, prevention and control of anisakiasis. Due to limitation of the morphological characters (easily influenced by environmental factors) and few gene sequences (lack of efficient genetic sites) in anisakid nematodes, over the last years, there has been considerable debate as to the classification and higher-level systematics of the family Anisakidae. Mitochondrial (mt) genome sequence provides useful genetic markers for investigating the taxonomy, population genetics and phylogenetics of parasites, but complete mt genomic data have been lacking for most anisakid nematodes. To date, complete mt genomes have been reported for only four species in the Anisakidae. In order to clarify cryptic/complex/sibling species in anisakid nematodes, we aimed determine the mt genomes of representatives of this family, analyze the structural features of their mt genomes, and construct the phylogenetic relationships of anisakid nematodes. Furthermore, combined with the results of mt genomic and phylogenetic analyses and the relative biological characteristics, we will examine the higher-level systematics of Anisakidae. These mt genomes not only provide a useful markers to solve taxonomic status of anisakid nematodes but also lay the theoretical foundation for diagnosis, treatment and prevention of anisakiasis.

对异尖线虫进行准确的鉴定和分类是诊断、防治和控制异尖线虫病的前提和基础。由于形态学（易受环境影响）和少量基因片段序列（缺乏有效的遗传信息位点）在分类上的局限性，异尖科线虫分类和其高级阶元的系统发育仍颇具争议。线粒体基因组序列是研究寄生虫分子分类、群体遗传、系统进化的一种很好的分子标记，然而关于异尖科这一重要类群线粒体基因组的研究较少，目前仅4种异尖科线虫线粒体基因组被解码。申请者拟解码该科代表种线粒体基因组，分析其线粒体基因组结构特征并构建其与其他线虫的系统发育关系，以期阐明异尖科线虫隐藏种、复合种或姊妹种的分类问题。此外，综合线粒体基因组学和系统发育的结果及其相关生物学特性，进一步探讨异尖科高级阶元分类地位及系统发育学。本研究不仅可基本解决异尖线虫的分类问题，而且也可为异尖线虫病的诊断、治疗和防治提供理论依据。

对异尖线虫进行准确的鉴定和分类是诊断、防治和控制异尖线虫病的前提和基础。由于形态学（易受环境影响）和少量基因片段序列（缺乏有效的遗传信息位点）在分类上的局限性，异尖科线虫分类和其高级阶元的系统发育仍颇具争议。线粒体基因组序列是研究寄生虫分子分类、群体遗传、系统进化的一种很好的分子标记。申请者解码了该科8种代表种线粒体基因组，分析其线粒体基因组结构特征并构建其与其他线虫的系统发育关系。结果表明异尖科和蛔科的亲缘关系比和弓首科的亲缘关系更接近。提出了拟地新线虫至少包含6个隐藏种/姐妹种和来自不同国家和宿主的欧氏对盲囊线虫是一个种的新假说。这些关键数据上传到了NCBI数据库，也获得了基因注册（KU558720-KU558727）。本研究不仅为异尖线虫的分子流行病学、群体遗传学和系统分类学研究奠定基础，而且也可为异尖线虫病的诊断、治疗和防治提供理论依据。