The mitochondrial genome of the blowfly Chrysomya chloropyga (Diptera: Calliphoridae)

In view of the medical, sanitary and forensic importance of Chrysomya species, a knowledge of their nucleotide sequences would be useful for the molecular characterization of this genus, and would help in designing primers and in improving the molecular identification of Calliphoridae species. In this work, the mitochondrial genome of the blowfly Chrysomya chloropyga (Diptera: Calliphoridae) was completely sequenced. The entire mitochondrial DNA (mtDNA) molecule was 15,837 bp long and was sequenced using the shotgun approach. The overall nucleotide composition was heavily biased towards As and Ts, which accounted for 76.7% of the whole genome. The cox1 gene had a serine as the start codon, while incomplete termination codons mediated by tRNA signals were found for cox2, nd4 and nd5. The C. chloropyga genes were in the same order and orientation as the mitochondrial genome of other dipteran species, except for the occurrence of a 123 bp region that included a complete duplication of tRNA(Ile) and a partial duplication of tRNA(Gln), genes. C. chloropyga is the first species of Diptera with 23 tRNA genes instead of the usual 22 already described. A phylogenetic analysis showed a split of Brachycera into Calyptratae and Acalyptratae subdivisions. The complete sequence of C. chloropyga mtDNA described here will be a useful source of sequence information for general molecular and evolutionary studies in Diptera. (C) 2004 Elsevier B.V. All rights reserved.