Total mitochondrial genome characteristics in Poecilimon luschani and Isophya major ( Orthoptera, Tettigoniidae )

Over the last 20 years, sequences of the mitochondrial genome have been one of the main sources of data used in molecular evolution, population genetics, phylogenetic and other similar fields. Of the 30.000 species belonging to the Orthoptera order, only mt-genomes of 149 have been sequenced and characterized. In this study, mt-genome of two species representing the subfamily of Phaneropterinae (Orthoptera, Tettigoniidae) were sequenced via the next generation sequencing and characterized comparatively using bioinformatics approaches. Mt-genome lengths were 15.724 and 15.568 base pairs in Isophya major and Poecilimon luschani respectively. The mt-genomes of both species are composed of 13 protein coding, 2 rRNA and 22 tRNA genes and an AT-rich region as the typical for other eukaryotes. The location of 37 genes in both species is identical to the Pantrustaceae mt-genome, which is regarded as the ancestral insect mt-genome. Different than the other a 183 base pair long non-coding region located between trnR and trnN genes was identified in I. major, and this region displays a double consecutively repeating motif. In the protein coding genes the AT/GC ratios were found to be 65,4/34,6 and 68,4/31,6 in in I. major and P. luschani respectively. In the light of these data following conclusions were made: (i) These two species show the typical multicellular mt-genome characteristics in terms of length and number of genes in the mt-genome, (ii) The ancestral gene locations are conserved in these two species which representing the tribe Barbitistini, (iii) this gene arrangement is different that gene locations in some other lineages in Phaneropterinae subfamily, (iv) both species have an AT-rich genome, and (v) The non-coding region of the 183 base pair length detected in I. major species may have been generated during mt-genomic replication or contain the transcription initiation region.