title: Comparative analysis of the mitochondrial genomes of Callitettixini Spittlebugs (Hemiptera: Cercopidae) confirms the overall high evolutionary speed of the AT-rich region but reveals the presence of short conservative elements at the tribal level.
abstract: The present study compares the mitochondrial genomes of five species of the spittlebug tribe Callitettixini (Hemiptera: Cercopoidea: Cercopidae) from eastern Asia. All genomes of the five species sequenced are circular double-stranded DNA molecules and range from 15,222 to 15,637 bp in length. They contain 22 tRNA genes, 13 protein coding genes (PCGs) and 2 rRNA genes and share the putative ancestral gene arrangement of insects. The PCGs show an extreme bias of nucleotide and amino acid composition. Significant differences of the substitution rates among the different genes as well as the different codon position of each PCG are revealed by the comparative evolutionary analyses. The substitution speeds of the first and second codon position of different PCGs are negatively correlated with their GC content. Among the five species, the AT-rich region features great differences in length and pattern and generally shows a 2-5 times higher substitution rate than the fastest PCG in the mitochondrial genome, atp8. Despite the significant variability in length, short conservative segments were identified in the AT-rich region within Callitettixini, although absent from the other groups of the spittlebug superfamily Cercopoidea.
authors.affiliation: Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, P. R. China; Graduate University of the Chinese Academy of Sciences, Shijingshan District, Beijing, P. R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.affiliation: Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, P. R. China; Jiangsu Key Laboratory for Eco-Agricultural Biotechnology around Hongze Lake, Huaiyin Normal University, Huaian, Jiangsu Province, P. R. China.
authors.forename: Cuiping
authors.initials: C
authors.lastname: Bu
authors.affiliation: Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, P. R. China.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Wipfler
authors.affiliation: Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, P. R. China.
authors.forename: Aiping
authors.initials: A
authors.lastname: Liang
mesh_terms: D020856:AT Rich Sequence / Q000235:genetics*; D000818:Animals; D001482:Base Composition / Q000235:genetics; D001483:Base Sequence; D001499:Bayes Theorem; D017124:Conserved Sequence / Q000235:genetics*; D021901:DNA, Intergenic / Q000235:genetics; D019143:Evolution, Molecular; D054629:Genome, Mitochondrial / Q000235:genetics*; D006430:Hemiptera / Q000235:genetics*; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009711:Nucleotides / Q000235:genetics; D016366:Open Reading Frames / Q000235:genetics; D010802:Phylogeny; D012335:RNA, Ribosomal / Q000235:genetics; D012343:RNA, Transfer / Q000235:genetics; D015203:Reproducibility of Results; D020080:Tandem Repeat Sequences / Q000235:genetics
chemical_list: D021901:DNA, Intergenic; D009711:Nucleotides; D012335:RNA, Ribosomal; D012343:RNA, Transfer