Molecular evolution of the mitochondrial genome of the family Calliphoridae (Diptera: Brachycera)

Author(s)

Ana Carolina Martins Junqueira

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia
• Defense date: 2008-02-29

Examining board members

Ana Maria Lima de Azeredo Espin; Cristina Yumi Miyaki; João Miguel de Barros Alexandrino; André Victor Lucci Freitas; Gonçalo Amarante Guimarães Pereira

• Advisor: Ana Maria Lima de Azeredo Espin; Claudia Augusta de Moraes Russo

Abstract

In this study, we present the complete mitochondrial DNA (mtDNA) sequence of three Calliphoridae (Diptera: Brachycera) species: Chloroprocta idioidea, Calliphora vomitoria and Phormia regina, which had 15004, 16143 and 16635 bp, respectively. Each genome was arranged in the same order described for insects and crustaceans, containing 13 protein coding genes (PCGs), two ribossomal RNA subunits (rRNA) and twenty-two transfer RNA (tRNA), with the exception of P. regina, which presented a duplication involving the complete sequences of tRNAIle and tRNAGln genes, besides a partial sequence of the tRNAMet. A similar duplication has been previously described for Chrysomya species in the same location, inserted in the hypervariable domain of the mitochondrial control region. The nucleotide composition was heavily biased toward As and Ts (71.7% for C. idioidea, 72.9% for C. vomitoria and 75.6% for P.regina), mainly when considering third codon positions and non-coding regions, where the A+T content was >90%. The phylogenetic reconstructions were conducted for all available dipteran species in GenBank, this being the most comprehensive study carried out so far with complete mitochondrial genome sequences. The use of single genes has shown that different topologies were obtained with low support, whereas the use of nucleotide and amino-acid data sets with concatenated PCGs usually provided resolution for intraordinal relationships in Diptera. The monophyly of Muscomorpha was not supported in our analyses, as well as the monophyly of Acalyptratae, which is a major clade of Schizophora. The Calliphoridae was a monophyletic family, but the superfamily Oestroidea was disrupted by the inclusion of Muscoidea species as a sister group of Calliphoridae. Within Calliphoridae, the subfamilies Luciliinae and Calliphorinae were clustered together, related to the Chrysomyinae subfamily. In view of its sanitary, medical, economic and forensic importance, knowledge of Calliphoridae relationships is of interest to guide future works on parasitism evolution of the myiasis habit and specific molecular diagnosis of species. In addition, the characterization of complete mitochondrial sequences could provide insights with regard to dipteran relationships and general molecular evolutionary studies on deep-level phylogenies of insects. (AU)