The long-term goal of this research is to understand the molecular action and resistance mechanisms of two important classes of insecticides, pyrethroids and sodium channel blocker insecticides (SCBIs). Strategies for the control of arthropod pests of major public health concerns continue to rely heavily on the use of relatively safe insecticides. Currently, pyrethroids are the only class of insecticides used in insecticide treated nets (ITNs) for malaria control, due to their fast acting, high efficacy, and relative low toxicity to humans. However, a major threat to the sustained use of pyrethroids is the development of resistance. Indoxacarb and its active metabolite (DCJW), the first member of a new class of SCBIs, also meets vector control criteria, and could be an alternative insecticide to pyrethroids. Both pyrethroids and indoxacarb target voltage-gated sodium channels;however, the modes of their action are not well understood at the molecular level, which presents a major obstacle to the characterization of mechanisms of resistance.
The specific aims of this renewal proposal are: 1) Characterization of the molecular basis of pyrethroid action and resistance, and 2) Identification of the receptor site and molecular action of indoxacarb/DCJW on sodium channels. A combination of molecular, electrophysiological, and computer modeling methods will be used to test novel hypotheses, with the final goal of defining the molecular identities of the elusive pyrethroid and indoxacarb receptor sites on the insect sodium channel. New knowledge gained from this fundamental research will have significant impact on future development of effective monitoring and management strategies for controlling major human health-threatening arthropod pests.
This application describes basic research to understand how pyrethroid and indoxacarb insecticides interact with the voltage-gated sodium channel at the molecular level and how insect pests develop resistance to these insecticides. The knowledge gained from this research will have important implications for the development of strategies to control arthropod vectors that transmit important human diseases including malaria.
|Dong, Ke; Du, Yuzhe; Rinkevich, Frank et al. (2014) Molecular biology of insect sodium channels and pyrethroid resistance. Insect Biochem Mol Biol 50:1-17|
|Gao, R; Du, Y; Wang, L et al. (2014) Sequence variations at I260 and A1731 contribute to persistent currents in Drosophila sodium channels. Neuroscience 268:297-308|
|Du, Yuzhe; Nomura, Yoshiko; Satar, Gul et al. (2013) Molecular evidence for dual pyrethroid-receptor sites on a mosquito sodium channel. Proc Natl Acad Sci U S A 110:11785-90|
|Rinkevich, Frank D; Du, Yuzhe; Dong, Ke (2013) Diversity and Convergence of Sodium Channel Mutations Involved in Resistance to Pyrethroids. Pestic Biochem Physiol 106:93-100|
|Wang, Lingxin; Nomura, Yoshiko; Du, Yuzhe et al. (2013) Differential effects of TipE and a TipE-homologous protein on modulation of gating properties of sodium channels from Drosophila melanogaster. PLoS One 8:e67551|
|Oliveira, Eugenio E; Du, Yuzhe; Nomura, Yoshiko et al. (2013) A residue in the transmembrane segment 6 of domain I in insect and mammalian sodium channels regulate differential sensitivities to pyrethroid insecticides. Neurotoxicology 38:42-50|
|Song, Weizhong; Du, Yuzhe; Liu, Zhiqi et al. (2011) Substitutions in the domain III voltage-sensing module enhance the sensitivity of an insect sodium channel to a scorpion beta-toxin. J Biol Chem 286:15781-8|
|Du, Yuzhe; Garden, Daniel; Khambay, Bhupinder et al. (2011) Batrachotoxin, pyrethroids, and BTG 502 share overlapping binding sites on insect sodium channels. Mol Pharmacol 80:426-33|
|Du, Yuzhe; Khambay, Bhupinder; Dong, Ke (2011) An important role of a pyrethroid-sensing residue F1519 in the action of the N-alkylamide insecticide BTG 502 on the cockroach sodium channel. Insect Biochem Mol Biol 41:446-50|
|Hu, Zhaonong; Du, Yuzhe; Nomura, Yoshiko et al. (2011) A sodium channel mutation identified in Aedes aegypti selectively reduces cockroach sodium channel sensitivity to type I, but not type II pyrethroids. Insect Biochem Mol Biol 41:9-13|
Showing the most recent 10 out of 24 publications