State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China.
Department of Zoology, University of Swabi, Khyber Pakhtunkhwa, Pakistan.
Parasitol Res. 2019 Jul;118(7):2203-2211. doi: 10.1007/s00436-019-06358-y. Epub 2019 Jun 1.
Mitochondrial (mt) DNA has been useful in revealing the phylogenetic relationship of eukaryotic organisms including flatworms. Therefore, the use of mitogenomic data for the comparative and phylogenetic purposes is needed for those families of digenetic trematodes for which the mitogenomic data are still missing. Molecular data with sufficiently rich informative characters that can better resolve species identification, discrimination, and membership in different genera is also required for members of some morphologically difficult families of trematodes bearing few autapomorphic characters among its members. Here, the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (rDNA) and the complete mt genome of the trematode Uvitellina sp. (Cyclocoelidae: Haematotrephinae) was determined and annotated. The mt genome of this avian trematode is 14,217 bp in length, containing 36 genes plus a single non-coding region. The ITS rDNA sequences were used for the pairwise sequence comparison of Uvitellina sp. with European cyclocoelid species, and the mitochondrial 12 protein-coding genes (PCGs) and two ribosomal RNA genes were used to evaluate the position of the family within selected trematodes. The ITS rDNA analysis of Uvitellina sp. showed less nucleotide differences with Hyptiasmus oculeus (16.77%) than with other European cyclocoelids (18.63-23.58%). The Bayesian inference (BI) analysis using the 12 mt PCGs and two rRNA genes supported the placement of the family Cyclocoelidae within the superfamily Echinostomatoidea (Plagiorchiida: Echinostmata). The availability of the mt genome sequences of Uvitellina sp. provides a novel resource of molecular markers for phylogenetic studies of Cyclocoelidae and other trematodes.
线粒体 (mt) DNA 在揭示包括扁形动物在内的真核生物的系统发育关系方面非常有用。因此，对于那些线粒体基因组数据仍然缺失的双肠类吸虫科，需要使用线粒体基因组数据进行比较和系统发育研究。对于那些形态上难以区分的吸虫科成员，还需要具有足够丰富的信息特征的分子数据，以便更好地解决物种鉴定、区分和不同属的归属问题，这些成员的特征在其成员中很少有独特的特征。在这里，确定并注释了核核糖体 DNA (rDNA) 的内部转录间隔区 (ITS) 区域和吸虫 Uvitellina sp. 的完整线粒体基因组。这种禽类吸虫的线粒体基因组长 14217bp，包含 36 个基因和一个单一的非编码区。使用 ITS rDNA 序列对 Uvitellina sp. 与欧洲环肠科物种进行了成对序列比较，并使用线粒体 12 个蛋白编码基因 (PCGs) 和两个核糖体 RNA 基因来评估该科在选定的吸虫中的位置。Uvitellina sp. 的 ITS rDNA 分析显示，与欧洲环肠科其他物种相比，与 Hyptiasmus oculeus 的核苷酸差异较小（16.77%）。使用 12 个 mt PCGs 和两个 rRNA 基因进行的贝叶斯推断 (BI) 分析支持将环肠科家族置于 Echinostomatoidea 超科（Plagiorchiida：Echinostmata）内。Uvitellina sp. 的线粒体基因组序列的可用性为环肠科和其他吸虫的系统发育研究提供了新的分子标记资源。
