Novel sodium channel gene mutations in Blattella germanica reduce the sensitivity of expressed channels to deltamethrin.

Journal Article (Journal Article)

Pyrethroid insecticides alter the normal gating of voltage-gated sodium channels in the nervous system. Three sodium channel mutations (E434K, C764R, L993F) were recently identified in pyrethroid resistant German cockroach populations. In this report, we show that the L993F mutation decreased sodium channel sensitivity to the pyrethroid, deltamethrin, by five-fold in Xenopus oocytes. In contrast, neither E434K nor C764R alone decreased channel sensitivity to deltamethrin. However, E434K or C764R combined with L993F reduced deltamethrin sensitivity by 100-fold. Furthermore, concomitant presence of all three mutations (KRF) reduced channel sensitivity to deltamethrin by 500-fold. None of the mutations significantly affected channel gating. However, sodium current amplitudes from the mutant sodium channel carrying either E434K or C764R alone were much reduced compared to those of the wild-type channel or the channel carrying the double or triple mutations (KF, RF and KRF). These results indicated that evolution of sodium channel insensitivity in the German cockroach is achieved by sequential selection of a primary mutation L993F and two secondary mutations E434K and C764R, and concomitant presence of all three mutations dramatically reduced sodium channel sensitivity to deltamethrin.

Full Text

Duke Authors

Cited Authors

  • Tan, J; Liu, Z; Tsai, T-D; Valles, SM; Goldin, AL; Dong, K

Published Date

  • April 2002

Published In

Volume / Issue

  • 32 / 4

Start / End Page

  • 445 - 454

PubMed ID

  • 11886779

Pubmed Central ID

  • PMC3057061

Electronic International Standard Serial Number (EISSN)

  • 1879-0240

International Standard Serial Number (ISSN)

  • 0965-1748

Digital Object Identifier (DOI)

  • 10.1016/s0965-1748(01)00122-9

Language

  • eng