关键词: 蚊虫, 线粒体DNA, 细胞色素C氧化酶亚基Ⅰ, 分子进化

Abstract: Objective To explore gene characteristics of mitochondrial DNA cytochrome C oxidase subunitⅠ (mtDNA-COⅠ) in nine common mosquito species and analyze the corresponding phylogenetic relationship of these mosquitoes. Methods Nine species of mosquitoes (Culex pipiens pallens, Cx. tritaeniorhynchus, Cx. bitaeniorhynchus, Aedes albopictus, Ae. vexans, Anopheles sinensis, Armigeres subalbatus, Mansonia uniformis, Coquillettidia ochracea) were collected with man-bait net trap from Beihu area of Jining district in 2016 and identified in the laboratory. Single mosquito genomic DNA was extracted from each species and mtDNA-COⅠ was specifically amplified by PCR and sequenced. Gene sequences were blasted in GenBank, compared and analyzed by Bioedit 7.0 and DNAman. The gene traits, transversion rates, and divergence times were analyzed by DNAStar、ClustalX 1.81 and Mega 6.0. The phylogenetic tree was constructed. Results The amplified mtDNA-COⅠfragments of nine species of mosquitoes were 528 bp with (A+T)contents 65.72%-69.32%. There were 375 conserved sites, 153 variable sites, 104 parsimony informative sites and 49 singleton sites in the sequences. The transversion rates were from 3.409% to 9.470%, and the divergence times were from 1.482×10⁶a to 4.117×10⁶a. The nucleotide sequence homology among the different mosquito species were 84.28%-92.94%. Molecular phylogenetic study showed that different species were clustered at their own branch at genus level, which was consistent with traditional morphological identification. Conclusion mtDNA-COⅠ can serve as a useful classification and identification molecular marker for different mosquito species and genus, providing a molecular method for the identification and phylogenetic analysis of the mosquitoes.

Key words: Mosquito, Mitochondrial DNA, Cytochrome C oxidase subunit Ⅰ, Molecular evolution