Li Ran, Lei Zhiming, Li Wenjuan, Zhang Wei, Zhou Changfa
The Key Laboratory of Jiangsu Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
Insects. 2021 Feb 16;12(2):170. doi: 10.3390/insects12020170.
Large intergenic spacers and tRNA gene duplications have been reported in several insect groups, although little is known about mitogenomes of mayflies. Here, we determined complete mitogenomes of ten heptageniid species and systemically analyzed their mitogenomic features. Both a conserved intergenic spacer (IGS) and duplication were detected in those mitogenomes. The IGS, which was observed in heptageniids, could be further folded into a stable stem-loop structure. The tRNA gene duplication was found in almost all analyzed mitogenomes, and a unique gene block ---- was also discovered. Our analysis demonstrates that the heptageniid gene arrangement pattern can be explained by the tandem duplication-random loss (TDRL) model. Phylogenetic analyses using both Bayesian inference (BI) and maximum likelihood (ML) methods based on the nucleotide and amino acid sequence data recovered the genus as monophyletic with strong support. Our results provide a better understanding of mitogenomic evolution in Heptageniidae, as well as novel molecular markers for species identification of mayflies.
在几个昆虫类群中已报道了大的基因间隔区和tRNA基因重复，尽管对蜉蝣的线粒体基因组了解甚少。在此，我们测定了10种扁蜉科物种的完整线粒体基因组，并系统分析了它们的线粒体基因组特征。在这些线粒体基因组中检测到了一个保守的基因间隔区（IGS）和重复序列。在扁蜉科中观察到的IGS可以进一步折叠成稳定的茎环结构。在几乎所有分析的线粒体基因组中都发现了tRNA基因重复，并且还发现了一个独特的基因块。我们的分析表明，扁蜉科的基因排列模式可以用串联重复-随机丢失（TDRL）模型来解释。基于核苷酸和氨基酸序列数据，使用贝叶斯推断（BI）和最大似然（ML）方法进行的系统发育分析有力支持地将该属恢复为单系类群。我们的结果为更好地理解扁蜉科的线粒体基因组进化以及蜉蝣物种鉴定的新分子标记提供了依据。
