CLONING AND SEQUENCING OF THE CYCLODIENE INSECTICIDE RESISTANCE GENE FROM THE YELLOW-FEVER MOSQUITO AEDES-AEGYPTI - CONSERVATION OF THE GENE AND RESISTANCE-ASSOCIATED MUTATION WITH DROSOPHILA

In order to examine the conservation of the mechanism of cyclodiene in secticide resistance between species we cloned a cDNA from the yellow fever mosquito Aedes aegypti homologous to the resistance gene Rdl in Drosophila. In D. melanogaster, resistance to cyclodienes and picrotox inin is caused by a single amino acid substitution (alanine to serine) in the putative channel lining of a gamma-aminobutyic acid gated chlo ride ion channel. We report that the mosquito gene not only shows high homology to that of Drosophila but also that resistant strains displa y substitution of the same amino acid. The significance of this result in relation to the evolution of pesticide resistance, the use of Dros ophila as a model insect for resistance studies and the potential use of this gene as a selectable marker in the genetic transformation of n on-Drosophilids is discussed.