Analysis Of The Four Locust Mitochondrial Genome Sequencing And Phylogenetic

Orthoptera insects include two categories:one for the long-horned suborder to katydids and crickets, represented by its long antennae longer than the body angle of insects, the other for a short corner suborder to locust and grasshopper as the representative body of its antennae shorter than the short-corner type insects.In this study, the mitochondrial DNA of four locusts was fully sequenced, including the genus of Sinopodisma and Pedopodisma. The possibility of establishing of genus Sinopodisma is controversial.1. The Pedopodisma emiensis(Yin) mt genome was16014bp in size, the Sinopodisma guizhouensis Zheng mt genome was16013bp in size, the Qinlingacris taibaiensis Yin et Chou mt genome was15631bp in size and the Oreoptygonotus chinghaiensis(Cheng et Hang) was15620bp in size. The four mitochondrial genomes contain a identical set of13protein-coding genes,22transfer RNA genes, two ribosomal RNA genes and an A+T-rich region in the same arrangenment and orientation as those of the other analysed caeliferan species.2. The nucleotide composition all showed A/T bias and the A+T content of four species mitogenomes showed little difference. The A+T content of Pedopodisma emiensis(Yin), Sinopodisma guizhouensis Zheng, Qinlingacris taibaiensis Yin et Chou and Oreoptygonotus chinghaiensis(Cheng et Hang)was76.5%,76.4%,76.3%and75.2%respectively.3. The AT rich region between srRNA and trnl. The size of AT rich region of Pedopodisma emiensis (Yin), Sinopodisma guizhouensis Zheng, Qinlingacris taibaiensis Yin et Chou and Oreoptygonotus chinghaiensis (Cheng et Hang) was1123bp,1127bp,778bp and711bp. AT content of the AT rich region of Pedopodisma emiensis (Yin), Sinopodisma guizhouensis Zheng, Qinlingacris taibaiensis Yin et Chou and Oreoptygonotus chinghaiensis (Cheng et Hang) was85.8%,84.8%,82.1%and88.7%.4. Each mitogenomes of four species has22tRNA. The pattern of nucleotide conservation in tRNA genes was majority strand-biased. AT content of tRNAs located on the majority strand were high than tRNAs that located on the minority strand. Each tRNA has the typical cloverleaf secondary structure found in most mt tRNA genes, except for tRNA-Ser(AGN), which lacks a DHU arm. Some unmatched base pairs occur in the Pedopodisma emiensis(Yi), Sinopodisma guizhouensis Zheng, Qinlingacris taibaiensis Yin et Chou, and Oreoptygonotus chinghaiensis(Cheng et Hang) tRNAs.5. The secondary structure of16s ribosomal genes are not form H1arm, in addition, mitochondrial rRNA secondary structure of other parts of the very conservative, forming a plurality of sizes of stem-loop structure. Nucleotide substitution rate of the ring to the stem, and C-T is a common form of conversion. Stems mostly nucleotide substitution mutation compensation to ensure that the base to maintain the existence of secondary structure.6.13protein-coding genes in four species of Catantopidae mitochondrial genome, there are11kinds of exactly the same size of protein-coding genes, only two different, cytb andnad3.7. Variation rate of cytb, coxl, cox2, cox3are low (The lowest is cytb, AVE=0.049). Variation rate of nadl, nad4, nad4L and nad5are moderate. Variation rate of atp8, nad3, nad2and nad6are rapid (The fast is nad3, AVE=0.153).8. The least P-distance between mtDNA is0.057(Sinopodisma guizhouensis Zheng to Sinopodisma houshana). The least P-distance between PCGs is0.056(Sinopodisma guizhouensis Zheng to Sinopodisma houshana). Indicate that two species in genus Sinopodisma is quite similar.9. T content of the four species of Catantopidae in J strand lower than N strand, A and C content in the J strand are higher than that of in N strand. The third site of codon of protein-coding genes in N strand show a very low G content, and has a very high T content.10. Based on PCGs, rRNA gene and whole37mitochondrial gene by using maximum parsimony, maximum likelihood and Bayesian inference method reconstructed phylogenetic tree Orthoptera, We consider that the exist of the genus Pedopodisma is reasonable.