Short Amount Of Negative Locust, Japan The Flea Cricket And China Atlas Grasshopper Mitochondrial Genome Sequencing And Analysis

Animal mitochondrial genome is a circular molecule, and used as a useful model for structural, functional and evolutionary genomics studies. Its structure and gene content are stable and predictable. Complete mitochondrial DNA sequences are being generated and released in the sequence databases at a very rapid rate. As of March 2008, complete mitochondrial genome sequences were available in Genbank for 1348 different species of plants, animals, fungi, and protists. Animal mitochondrial genome sequences are strongly over represented with 1195 species. Besides our own phylum Chordata, Arthropada is the best represented phylum, with 151 mitochondrial genome sequences.Orthoptera is one of most familiar among the insecta such as grasshoppers, cricket, long-horned grasshoppers, mole crickets and so on. By far, there are five Orthoptera mitochondrial genomes available in GenBank, belonging to Acridoidea, Tridactyloidea and Tettigonioidea. But there are no Tridactyloidea and other superfamilies' mitochondrial genomes available in GenBank. The phylogenetic relationships between two suborders and among families in Orthoptera are disputed, DNA sequence data from the mitochondrial genome are being used with increasingly frequency to estimate phylogenetic relationships among these taxa, but there are no consensus result by far.In this study, motichondrial genomes of three Orthoptera species were sequenced using the strategy of sub-PCR after long-PCR amplification. These sequences would enriched the database of mitochondrial genome sequences. We also use parts of mitochondrial genes to reconstruction Orthoptera phylogeny. The cinclusions are mainly summarized as follwing:1. The size and A+T composition of mitochondrial genomes of Atractomorpha sinensis,Tridactylus japonicus and Atlanticus sinensis are 15 558, 74.3%, 15 296, 71.5%, 15 811, 68.8%, respectively. They all have a remarkably conserved set of 37 genes and a control region. The gene order of Tridactylus japonicus and Atlanticus sinensis is the same as typical arthropod mitochondrial genome. The gene order of Atractomorpha sinensis is the same as the Locusta migratoria which has a KD reset.2. Most protein genes use the typical start codon ATN, except CO I gene of all three species (CCG) and ND2 genes of Tridactylus japonicas (GTG).3. Most protein genes use the typical and complete stop codon: TAA or TAG except ND5 gene of all three species and ATP8 of Atlanticus sinensis, which use the incomplete stop codons: TA or T. 4. All the 22 tRNA genes of Atractomorpha sinensis,Tridactylus japonicus and Atlanticus sinensis mitochondrial genomes have a typical clover leaf structure except tRNA Ser(AGN), which lack the DHU arm.5. The complete secondary structures of the 16S rRNA genes are predicted. There are 48-49, 31-33 stem-loop structure of 16S and 12S rRNA genes respectively. Most parts of the secondary structure among different species are similar.6. Phylogenetic analysis from the ND2, ND3, ND6, and tRNA genes support two suborder Caelifera and Ensifera as monophyletic groups. Tettigonioidea and Grylloidea were also supported as monophyletic groups. Within Acridoidea, Pyrgomorphidae and Chrotogonidae have closely relationships, and were the most ancestral groups among the 7 families. The monophyly of Catantopidae, Oedipodidae, Acrididae, and Arcypteridae were not supported in this study.