云斑车蝗线粒体基因组全序列测定与分析

采用长距 PCR 扩增及保守引物步移法并结合克隆测序测定并注释了云斑车蝗 Gastrimargus marmoratus （Thunberg）的线粒体基因组全序列。结果表明：云斑车蝗线粒体基因组全序列为15 904 bp（GenBank登录号为EU527334）,A+T含量略高于非洲飞蝗Locusta migratoria,为76.04%,包括13个蛋白质编码基因,22个tRNA 基因,2个rRNA基因和一段1 057 bp的A+T富集区。蛋白质基因的起始密码子中,除COⅠ和ND5为TTG以外,均为昆虫典型的起始密码子ATN。ND5基因使用了不完全终止密码子T,其余基因均为典型的TAA或TAG。预测了22个tRNA基因的二级结构,发现tRNA^Ser（AGN）缺少DHU臂, tRNA^Ser（UGY）的反密码子环上有9个碱基。预测了云斑车蝗12S和16S rRNA二级结构,分别包括3个结构域30个茎环和6个结构域44个茎环。A+T富集区含有3个串联重复序列。

Complete mitochondrial genome sequence of Gastrimargus marmoratus(Thunberg) (Orthoptera: Acridoidea)

The complete sequence of Gastrimargus marmoratus (Thunberg) mitochondrial genome was determined using long PCR and conserved primers walking approaches. The results showed that the entire mitochondrial genome of G. marmoratus (GenBank accession no. EU527334) is 15 904 bp in length with 76.5% A+T content. It contained 13 protein-coding genes, 2 ribosomal RNA genes, 22 tRNA genes, and an A+T-rich region of 1 057 bp. All protein-coding genes of the G. marmoratus mitochondrial genome start with a typical ATN codon, except for COⅠ and ND5 with TTG. The usual TAA and TAG termination codons were found for twelve protein-coding genes. However, the ND5 genes have an incomplete termination codon (T). With respect to the secondary structures of 22 tRNA genes, the absence of DHU arm of tRNA^Ser（AGN）was observed as in Locusta migratoria. tRNA^Ser（UGY）with 9 bases in anticodon loop was found, compared with typical 7 bases in others. The predicted secondary structures of 12S rRNA and 16S rRNA include 30 helices in 3 structural domains and 44 helices in 6 domains, respectively. The A+T content of the A+T-rich region is 76.5%, relatively higher than that of L. migratoria; three tandemly repeated DNA sequences were found in the A+T-rich region in G. marmoratus.