云南瘤蚱线粒体基因组特征与蚱总科系统发育分析

Mitochondrial genome characteristics and phylogenetic analysis of Thoradonta yunnana (Orthoptera: Tetrigoidea)

  • 摘要: 【目的】通过分析云南瘤蚱(Thoradonta yunnana)线粒体基因组结构特征,重建蚱总科系统发育关系,为进一步明确蚱总科各类群间的亲缘关系和进化位置提供理论依据。【方法】通过Illumina HiSeq 2500测序平台的二代测序技术对云南瘤蚱线粒体基因组进行测序,并结合已有的23种蚱类昆虫及2种蚤蝼科昆虫的线粒体蛋白编码基因(Protein-coding genes,PCGs)分别利用最大似然法(ML)和贝叶斯推断法(BI)构建蚱总科系统发育关系。【结果】云南瘤蚱线粒体基因组全长17859 bp,包括2个rRNA基因、22个tRNA基因、13个PCGs及一段非编码控制区。13个PCGs中,除nad6基因以TTG为起始密码子、nad5基因以不完整的T为终止密码子外,其余PCGs均以ATN作为起始密码子且以完整的TAA或TAG密码子终止。22个tRNA基因中,仅trnS1基因缺少DHU臂,其余基因均能折叠成三叶草二级结构。在云南瘤蚱线粒体基因组控制区中共发现6种重复序列,重复单元长度在29~204 bp不等。基于13个PCGs构建的ML法和BI法系统发育进化树拓扑结构基本一致,股沟蚱科和三棱角蚱科位于系统发育进化树的基部,属于较为原始的类群;刺翼蚱科、枝背蚱科及短翼蚱科位于发育进化树中部,属于中间类群;蚱亚科所有物种聚为一支,位于发育进化树顶部,属于较进化类群。【结论】研究结果支持蚱亚科为单系群,刺翼蚱科为并系群的观点,并在一定程度上验证了股沟蚱科属于较原始类群,蚱亚科属于较进化类群的观点。

     

    Abstract: 【Objective】 By analyzing the characteristics of the mitochondrial genome of Thoradonta yunnana, the phylogenetic relationship of Tetrigoidea was reconstructed, which provided a theoretical basis for further clarifying the genetic relationship and evolutionary position among various groups of Tetrigoidea.【Method】 The mitochondrial genome of T. yunnana was sequenced by Illumina HiSeq 2500 platform next-generation sequencing. Based on the protein-coding genes (PCGs) of 24 species of Tetrigoidea and 2 species of Tridactylidae, the phylogenetic tree was constructed by maximum likelihood(ML) method and Bayesian inference(BI) method respectively.【Result】 The total length of the mitogenome was 17859 bp, including 2 rRNA genes, 22 tRNA genes, 13 PCGs and one non-coding control region. Among the 13 PCGs, except for nad6 gene with TTG as the start codon and nad5 gene with incomplete T as the end codon, all PCGs had ATN as the start codon and end with complete TAA or TAG codon. Among the 22 tRNA genes, only trnS1 lacked the DHU arm, and the rest of the genes were able to fold into a clover leaf secondary structure. A total of six repetitive sequences were identified in the control region of T. yunnana, with repeat unit lengths ranging from 29 bp to 204 bp. The topology of two phylogenetic trees constructed based on 13 PCGs was essentially consistent. Batrachididae and Tripetaloceridae were located at the base of the phylogenetic tree and belonged to the more primitive groups. Scelimenidae, Cladonotidae and Metrodoridae were located in the middle of the developmental tree and belonged to the intermediate group. All species of Tetriginae were clustered into one branch, located at the top of the developmental tree, belonging to a more evolutionary group. 【Conclusion】 The results support the view that Tetriginae is a monophyletic group, and Scelimenidae is a paraphyletic group. To a certain extent, the evolutionary position of the Batrachididae as more primitive groups and Tetriginae in Tetrigoidea as more evolutionary group is verified.

     

/

返回文章
返回