Single channel analysis was used to compare the electrophysiological properties of wild-type (WT) and I874M mutant (M874) rat Na(V)1.2 channels expressed in Xenopus oocytes and their modulation by the pyrethroid deltamethrin. In the absence of pyrethroid, histograms of channel open times were best-fit by single exponentials.
View Article and Find Full Text PDFMutations in the DIIS4-S5 linker and DIIS5 have identified hotspots of pyrethroid and DDT interaction with the Drosophila para sodium channel. Wild-type and mutant channels were expressed in Xenopus oocytes and subjected to voltage-clamp analysis. Substitutions L914I, M918T, L925I, T929I and C933A decreased deltamethrin potency, M918T, L925I and T929I decreased permethrin potency and T929I, L925I and I936V decreased fenfluthrin potency.
View Article and Find Full Text PDFThe long term use of many insecticides is continually threatened by the ability of insects to evolve resistance mechanisms that render the chemicals ineffective. Such resistance poses a serious threat to insect pest control both in the UK and worldwide. Resistance may result from either an increase in the ability of the insect to detoxify the insecticide or by changes in the target protein with which the insecticide interacts.
View Article and Find Full Text PDFWe report the complete cDNA sequence of the Anopheles gambiae voltage-gated sodium channel (VGSC) alpha-subunit isolated from mature adult mosquitoes. The genomic DNA contains 35 deduced exons with a predicted translation of