The mitochondrial genome of the peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae): complete DNA sequence, genome organization, and phylogenetic analysis with other tephritids using next generation DNA sequencing

Abstract

Mitochondrial genome can provide information for genomic structure as well as for phylogenetic analysis and evolutionary biology. The complete 15,935 bpmitochondrial genome of Bactrocera zonata (Diptera: Tephritidae), is assembled from Illumina MiSeq read data. The mitogenome information for B. zonata was compared to the homologous sequences of other tephritids. Annotation indicated that the structure and orientation of 13 protein coding genes (PCGs), 22 tRNA and 2 rRNA sequences were typical of, and similar to, the ten closely related tephritid species. The nucleotide composition shows heavily biased toward As and Ts accounting 73.34% and exhibits a slightly positive AT skew, which is similar to other known tephritid species. All PCGs are initiated by ATN codons, except for cox1 with TCG and atp8 with GTG. Nine PCGs use a common stop codon of TAA or TAG,whereas the remaining four use an incomplete termination codon T or TA likely to be completed by adenylation. All tRNAs have the typical clover-leaf structure,with an exception for trnS(AGN). Four short intergenic spacers showed high degree of conservation among B. zonata and other ten tephritids. A poly(T) stretch at the 5′ end followed by [TA(A)]n-like stretch and a tandem repeats of 39 bp has been observed in CR. The analysis of gene evolutionary rate revealed that the cox1 and atp6 exhibits lowest and highest gene substitution rates, respectively than other genes. The phylogenetic relationships based onMaximumLikelihood method using all protein-coding genes and two ribosomal RNA genes confirmed that B. zonata is closely related to Bactrocera correcta, Bactrocera carambolae, Bactrocera papayae, and Bactrocera philippinensis and Bactrocera dorsalis belonging to B. dorsalis species complex forms a monophyletic clade, which is in accordance with the traditional morphological classification and recent molecular works.