Characterization of the nicotinic acetylcholine receptor subunit gene Mdα2 from the house fly, Musca domestica

Abstract

AbstractA nicotinic acetylcholine receptor (nAChR) subunit gene, Mdα2, was isolated and characterized from the house fly, Musca domestica. This is the first nAChR family member cloned from house flies. Mdα2 had a cDNA of 2,607 bp, which included a 696 bp 5′‐untranslated region (UTR), an open reading frame of 1,692 bp, and a 219 bp 3′‐UTR. Its deduced amino acid sequence possesses the typical characteristics of nAChRs. Mdα2 genomic sequence was 11.2 kb in length in the aabys strain and 10.9 kb in the OCR strain, including eight exons and seven introns. Based on the deduced amino acid sequence, Mdα2 had the closest phylogenetic relationship to the Drosophila melanogaster Dα2 and Anopheles gambiae Agamα2, and a similar genomic structure to Dα2. Quantitative real‐time PCR analysis showed that Mdα2 is expressed in the head and the thorax at 150‐ and 8.5‐fold higher levels than in the abdomen. Linkage analysis of a Mdα2 polymorphism indicates this gene is on autosome 2. The importance of these results in understanding the diversity and phylogenetic relationships of insect nAChRs, the physiology of nAChRs in the house fly, and the utility of nAChR sequences in resistance detection/monitoring is discussed. Arch. Insect Biochem. Physiol. 64:30–42, 2007. © 2006 Wiley‐Liss, Inc.