Key Laboratory of Marine Ranching, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fisheries Sciences, Guangzhou 510300, China.
Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, School of Life Science, South China Normal University, Guangzhou 510631, China.
Genes (Basel). 2022 Aug 1;13(8):1376. doi: 10.3390/genes13081376.
The capsalid monogeneans are important pathogens that generally infect marine fishes and have a substantial impact on fish welfare in aquaculture systems worldwide. However, the current mitogenome information on capsalids has received little attention, limiting the understanding of their evolution and phylogenetic relationships with other monogeneans. This paper reports the complete mitochondrial genomes of and for the first time, which we obtained using a next-generation sequencing method. The mitogenomes of and are 13,265 and 13,984 bp in length, respectively. Both species contain the typical 12 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a control region. The genome compositions show a moderate A+T bias (66.5% and 63.9% for and , respectively) and exhibit a negative AT skew but a positive GC skew in both species. One gene block rearrangement was found in in comparison with other capsalid species. Instead of being basal to the Gyrodactylidea and Dactylogyridea or being clustered with Dactylogyridea, all species of Capsalidea are grouped into a monophyletic clade. Our results clarify the gene rearrangement process and evolutionary status of Capsalidae and lay a foundation for further phylogenetic studies of monogeneans.
capsalid 单殖吸虫是一类重要的病原体，通常感染海洋鱼类，对全球水产养殖系统中的鱼类福利有重大影响。然而，目前 capsalids 的线粒体基因组信息受到的关注较少，限制了对其进化和与其他单殖吸虫的系统发育关系的理解。本文首次报道了 和 的完整线粒体基因组，我们使用下一代测序方法获得了这些基因组。 和 的线粒体基因组分别长 13265 和 13984bp。这两个物种都包含典型的 12 个蛋白编码基因、2 个核糖体 RNA 基因、22 个转移 RNA 基因和一个控制区。基因组组成表现出适度的 A+T 偏倚（ 和 分别为 66.5%和 63.9%），并且在两个物种中均表现出负的 AT 倾斜和正的 GC 倾斜。与其他 capsalid 物种相比， 在基因块排列上存在一个基因重排。所有的 Capsalidea 物种都被聚类为一个单系群，而不是位于 Gyrodactylidea 和 Dactylogyridea 的基部，或者与 Dactylogyridea 聚类在一起。我们的结果阐明了 Capsalidae 的基因重排过程和进化地位，为进一步研究单殖吸虫的系统发育奠定了基础。
