Federal Scientific Center of the East Asia Terrestrial Biodiversity, Far Eastern Branch of the RAS, Vladivostok, Russia.
Department of Cell Biology and Genetics, Far Eastern Federal University, Vladivostok, Russia.
J Helminthol. 2022 Jul 27;96:e54. doi: 10.1017/S0022149X22000438.
We obtained new data on the complete mitochondrial DNA (mtDNA) and the ribosomal operon of the trematode (Digenea: Haploporata: Haploporidae), an intestinal parasite of , using next-generation sequencing. The mtDNA of . contained 13,965 bp, including 12 protein-coding genes, two ribosomal genes, 22 transport RNA (tRNA) genes and a non-coding region. The ribosomal operon of . was 10,644 bp in length, including ETS1 (1449 bp), 18S ribosomal RNA (rRNA) gene (1988 bp), ITS1 ribosomal DNA (rDNA) (558 bp), 5.8S rRNA gene (157 bp), ITS2 rDNA (274 bp), 28S rRNA gene (4152 bp) and ETS2 (2066 bp). Phylogenetic analysis based on mtDNA protein-coding regions showed that . was closely related to , a species from the same suborder Haploporata. Bayesian phylogenetic tree topology was the most reliable and confirmed the validity of the Haploporata. The results of sequence cluster analysis based on codon usage bias demonstrated some agreement with the results of the phylogenetic analysis. In particular, spp. were differentiated from the other members of Digenea and the members of Pronocephalata were localized within the same cluster. and . fell within different clusters. The grouping of . and . within the same cluster was obtained on the basis of frequencies of 13 specified codons, of which three codon pairs were degenerate. A similarity was found between two haploporid species and two spp. in the presence of TTG start codon of the mitochondrial 5 gene. Our results confirmed the taxonomical status of the Haploporata identified in the previous studies and revealed some characteristic features of the codon usage in its representatives.
我们使用下一代测序技术获得了肠道寄生虫 （吸虫纲：单殖亚纲：单殖科）的完整线粒体 DNA（mtDNA）和核糖体基因座的新数据。 的 mtDNA 含有 13965bp，包括 12 个蛋白质编码基因、2 个核糖体基因、22 个转运 RNA（tRNA）基因和一个非编码区。 的核糖体基因座长 10644bp，包括 ETS1（1449bp）、18S 核糖体 RNA（rRNA）基因（1988bp）、ITS1 核糖体 DNA（rDNA）（558bp）、5.8S rRNA 基因（157bp）、ITS2 rDNA（274bp）、28S rRNA 基因（4152bp）和 ETS2（2066bp）。基于 mtDNA 蛋白质编码区的系统发育分析表明， 与同亚目单殖亚纲的 密切相关。贝叶斯系统发育树拓扑结构最可靠，证实了单殖亚纲的有效性。基于密码子使用偏性的序列聚类分析结果与系统发育分析结果有些一致。特别是， spp. 与吸虫纲的其他成员和 Pronocephalata 的成员分化开来，而 Pronocephalata 的成员则位于同一聚类中。 和 属于不同的聚类。在基于 13 个指定密码子的频率的基础上， 和 被分组到同一个聚类中，其中三个密码子对是简并的。在存在线粒体 5 基因 TTG 起始密码子时，两个单殖目物种和两个 属种之间存在相似性。我们的结果证实了先前研究中确定的单殖亚纲的分类地位，并揭示了其代表的密码子使用的一些特征。
