Extensive gene rearrangements in the mitochondrial genomes of two egg parasitoids, Trichogramma japonicum and Trichogramma ostriniae (Hymenoptera: Chalcidoidea: Trichogrammatidae)

• Published in: Scientific reports Vol. 8; no. 1; pp. 7034 - 11
• Main Authors: Chen, Long, Chen, Peng-Yan, Xue, Xiao-Feng, Hua, Hai-Qing, Li, Yuan-Xi, Zhang, Fan, Wei, Shu-Jun
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 04-05-2018; Nature Publishing Group; Nature Portfolio
• Subjects: 45/23; 45/77; 631/181/757; 631/601/1466; Chalcidoidea; Gene order; Gene rearrangement; Genes; Genomes; Humanities and Social Sciences; Hymenoptera; Insects; Mitochondria; Mitochondrial DNA; multidisciplinary; Parasitoids; Phylogeny; Proteins; Science; Science (multidisciplinary); Trichogramma japonicum; Trichogramma ostriniae; Trichogrammatidae; tRNA
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-018-25338-3

Animal mitochondrial genomes usually exhibit conserved gene arrangement across major lineages, while those in the Hymenoptera are known to possess frequent rearrangements, as are those of several other orders of insects. Here, we sequenced two complete mitochondrial genomes of
Trichogramma japonicum
and
Trichogramma ostriniae
(Hymenoptera: Chalcidoidea: Trichogrammatidae). In total, 37 mitochondrial genes were identified in both species. The same gene arrangement pattern was found in the two species, with extensive gene rearrangement compared with the ancestral insect mitochondrial genome. Most tRNA genes and all protein-coding genes were encoded on the minority strand. In total, 15 tRNA genes and seven protein-coding genes were rearranged. The rearrangements of
cox1
and
nad2
as well as most tRNA genes were novel. Phylogenetic analysis based on nucleotide sequences of protein-coding genes and on gene arrangement patterns produced identical topologies that support the relationship of (Agaonidae + Pteromalidae) + Trichogrammatidae in Chalcidoidea. CREx analysis revealed eight rearrangement operations occurred from presumed ancestral gene order of Chalcidoidea to form the derived gene order of
Trichogramma
. Our study shows that gene rearrangement information in Chalcidoidea can potentially contribute to the phylogeny of Chalcidoidea when more mitochondrial genome sequences are available.