Table1_Comparative mitogenomes reveal diverse and novel gene rearrangements in the genus Meteorus (Hymenoptera: Braconidae).XLSX

Meteorus Haliday, 1835 is a cosmopolitan genus within Braconidae (Hymenoptera). They are koinobiont endoparasitoids of Coleoptera or Lepidoptera larvae. Only one mitogenome of this genus was available. Here, we sequenced and annotated three mitogenomes of Meteorus species, and found that the tRNA gene rearrangements in these mitogenomes were rich and diverse. Compared with the ancestral organization, only seven tRNAs (trnW, trnY, trnL2, trnH, trnT, trnP and trnV) were conserved and trnG had its own unique location in the four mitogenomes. This dramatic tRNA rearrangement was not observed in mitogenomes of other insect groups before. In addition, the tRNA cluster (trnA-trnR-trnN-trnS1-trnE-trnF) between nad3 and nad5 was rearranged into two patterns, i.e., trnE-trnA-trnR-trnN-trnS1 and trnA-trnR-trnS1-trnE-trnF-trnN. The phylogenetic results showed that the Meteorus species formed a clade within the subfamily Euphorinae, and were close to Zele (Hymenoptera, Braconidae, Euphorinae). In the Meteorus, two clades were reconstructed: M. sp. USNM and Meteorus pulchricornis forming one clade while the remaining two species forming another clade. This phylogenetic relationship also matched the tRNA rearrangement patterns. The diverse and phylogenetic signal of tRNA rearrangements within one genus provided insights into tRNA rearrangements of the mitochondrial genome at genus/species levels in insects.

Meteorus Haliday, 1835，作为 Braconidae 科（膜翅目）中的一种世界性属，其物种为 Coleoptera 或 Lepidoptera 蝗虫幼虫的共栖内寄生性昆虫。该属中仅有一份线粒体基因组资料。本研究中，我们对三种 Meteorus 物种的线粒体基因组进行了测序和注释，并发现这些线粒体基因组中的转运RNA基因重排丰富且多样。与祖先基因组组织相比，仅有七个转运RNA（trnW、trnY、trnL2、trnH、trnT、trnP 和 trnV）得以保留，而 trnG 在四个线粒体基因组中具有其独特的定位。这种显著的转运RNA重排现象在以往其他昆虫类群的线粒体基因组中未曾观察到。此外，nad3 和 nad5 之间的转运RNA簇（trnA-trnR-trnN-trnS1-trnE-trnF）重排为两种模式，即 trnE-trnA-trnR-trnN-trnS1 和 trnA-trnR-trnS1-trnE-trnF-trnN。系统发育分析结果表明，Meteorus 物种在 Euphorinae 亚科中形成一个类群，且与 Zele（膜翅目，Braconidae 科，Euphorinae 亚科）亲近。在 Meteorus 中，重建了两个类群：M. sp. USNM 和 Meteorus pulchricornis 形成一个类群，而剩余两种物种形成另一个类群。这一系统发育关系也与转运RNA重排模式相吻合。一个属内转运RNA重排的多样性和系统发育信号为昆虫线粒体基因组在属/种水平上的转运RNA重排提供了洞见。