Sercundes Michelle Klein, Valadas Samantha Yuri Oshiro Branco, Keid Lara Borges, Oliveira Tricia Maria Ferreira Souza, Ferreira Helena Lage, Vitor Ricardo Wagner de Almeida, Gregori Fábio, Soares Rodrigo Martins
Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brasil.
Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo, Pirassununga, SP, Brasil.
Rev Bras Parasitol Vet. 2016 Jan-Mar;25(1):82-9. doi: 10.1590/S1984-29612016015. Epub 2016 Mar 18.
Phylogenies within Toxoplasmatinae have been widely investigated with different molecular markers. Here, we studied molecular phylogenies of the Toxoplasmatinae subfamily based on apicoplast and mitochondrial genes. Partial sequences of apicoplast genes coding for caseinolytic protease (clpC) and beta subunit of RNA polymerase (rpoB), and mitochondrial gene coding for cytochrome B (cytB) were analyzed. Laboratory-adapted strains of the closely related parasites Sarcocystis falcatula and Sarcocystis neurona were investigated, along with Neospora caninum, Neospora hughesi, Toxoplasma gondii (strains RH, CTG and PTG), Besnoitia akodoni, Hammondia hammondiand two genetically divergent lineages of Hammondia heydorni. The molecular analysis based on organellar genes did not clearly differentiate between N. caninum and N. hughesi, but the two lineages of H. heydorni were confirmed. Slight differences between the strains of S. falcatula and S. neurona were encountered in all markers. In conclusion, congruent phylogenies were inferred from the three different genes and they might be used for screening undescribed sarcocystid parasites in order to ascertain their phylogenetic relationships with organisms of the family Sarcocystidae. The evolutionary studies based on organelar genes confirm that the genus Hammondia is paraphyletic. The primers used for amplification of clpC and rpoB were able to amplify genetic sequences of organisms of the genus Sarcocystisand organisms of the subfamily Toxoplasmatinae as well.
弓形虫亚科内的系统发育已通过不同分子标记进行了广泛研究。在此，我们基于质体和线粒体基因研究了弓形虫亚科的分子系统发育。分析了编码酪蛋白水解蛋白酶（clpC）的质体基因和RNA聚合酶β亚基（rpoB）的部分序列，以及编码细胞色素B（cytB）的线粒体基因。研究了实验室适应的近缘寄生虫——犬小孢子虫和新孢子虫，以及犬新孢子虫、休氏新孢子虫、刚地弓形虫（RH、CTG和PTG株）、阿科多尼贝斯诺孢子虫、哈蒙德孢子虫、哈蒙德氏海多尼的两个遗传分化谱系。基于细胞器基因的分子分析未能明确区分犬新孢子虫和休氏新孢子虫，但确认了哈蒙德氏海多尼的两个谱系。在所有标记中都发现了犬小孢子虫和新孢子虫菌株之间的细微差异。总之，从这三个不同基因推断出了一致的系统发育，它们可用于筛选未描述的肉孢子虫寄生虫，以确定它们与肉孢子虫科生物的系统发育关系。基于细胞器基因的进化研究证实，哈蒙德孢子虫属是并系的。用于扩增clpC和rpoB的引物也能够扩增肉孢子虫属生物和弓形虫亚科生物的基因序列。
