背景:据报道,来自朝鲜半岛的一种新的Liobagrus鱼,但是缺乏对这个分类单元的研究。此外,在韩国,对Liobagrus属的有丝分裂基因组的研究非常有限,尚未对转移RNA(tRNA)的结构特征或分类单元之间的基因顺序比较进行研究;相反,研究仅限于基本的系统发育。
目的:首次分析了猪八哥的完整线粒体基因组。然后,我们旨在重建Liobagrus属的系统发育关系,并估计物种形成事件的发散时间。
方法:我们使用了从Liobagrusgeumgangensis成虫身上解剖的鳍夹。提取基因组DNA并用全基因组测序(WGS)进行分析,并通过NOVOPlasty方法进行组装。有丝分裂基因组序列被注释,和基因组图谱,tRNA结构,并使用最大似然分析构建系统发育树。此外,估计了发散时间。
结果:线粒体基因组长度为16,522bp,包含37个基因。总的基础成分是30.5%A,25.5%T,28.4%C,和15.7%G。大多数tRNA表现出典型的三叶草叶形状,除了trnS1。系统发育分析显示,Liobragrusgeumgangensis与朝鲜半岛南部地区独有的其他四种Liobragrus物种聚集在一个进化枝中。估计其分歧发生在新世晚期。
结论:猪八哥有丝分裂体的特征与其他洪流cat鱼的特征一致。时间尺度估计显示出不同的分组,其中一些分布在亚洲大陆,另一些分布在朝鲜半岛南部地区。值得注意的是,朝鲜半岛集团被确定为自己的血统,包括完全特有的物种。
BACKGROUND: A new Liobagrus fish was reported from the Korean Peninsula, but research on this taxon is lacking. Moreover, existing research on the mitogenome of the genus Liobagrus in Korea is very limited, and no studies have been conducted on structural characteristics of transfer RNA (tRNA) or gene order comparisons between taxa; instead, research has been restricted to basic phylogeny.
OBJECTIVE: The complete mitochondrial genome of Liobagrus geumgangensis was analyzed for the first time. We then aimed to reconstruct the phylogenetic relationships of the genus Liobagrus and estimate the divergence time of speciation events.
METHODS: We used a dissected fin clip from an adult of Liobagrus geumgangensis. Genomic DNA was extracted and analyzed with whole genome sequencing (WGS) and assembled by the NOVOPlasty method. The mitogenome sequence was annotated, and a genome map, tRNA structure, and phylogenetic tree were constructed using maximum likelihood analysis. In addition, divergence time was estimated.
RESULTS: The mitochondrial genome was 16,522 bp in length and comprised 37 genes. The overall base composition was 30.5% A, 25.5% T, 28.4% C, and 15.7% G. Most tRNAs exhibited the typical clover leaf shape, except trnS1. Phylogenetic analysis revealed that Liobagrus geumgangensis clustered within a clade with four other Liobagrus species exclusive to the southern region of the Korean Peninsula. Its divergence was estimated to have occurred during the late Miocene.
CONCLUSIONS: Characteristics of Liobagrus geumgangensis mitogenome were consistent with those of other torrent catfish species. Time scale estimation revealed distinct groupings, with some distributed across mainland Asia and others in the southern region of the Korean Peninsula. Notably, the Korean Peninsula group was identified as its own lineage, comprising entirely endemic species.