Distinct roles of two RDL GABA receptors in fipronil action in the diamondback moth (Plutella xylostella).

Journal Article (Journal Article)

The phenylpyrazole insecticide fipronil blocks resistance to dieldrin (RDL) γ-aminobutyric acid (GABA) receptors in insects, thereby impairing inhibitory neurotransmission. Some insect species, such as the diamondback moth (Plutella xylostella), possess more than one Rdl gene. The involvement of multiple Rdls in fipronil toxicity and resistance remains largely unknown. In this study, we investigated the roles of two Rdl genes, PxRdl1 and PxRdl2, in P. xylostella fipronil action. In Xenopus oocytes, PxRDL2 receptors were 40 times less sensitive to fipronil than PxRDL1. PxRDL2 receptors were also less sensitive to GABA compared with PxRDL1. Knockout of the fipronil-sensitive PxRdl1 reduced the fipronil potency 10-fold, whereas knockout of the fipronil-resistant PxRdl2 enhanced the fipronil potency 4.4-fold. Furthermore, in two fipronil-resistant diamondback moth field populations, PxRdl2 expression was elevated 3.7- and 4.1-fold compared with a susceptible strain, whereas PxRdl1 expression was comparable among the resistant and susceptible strains. Collectively, our results indicate antagonistic effects of PxRDL1 and PxRDL2 on fipronil action in vivo and suggest that enhanced expression of fipronil-resistant PxRdl2 is potentially a new mechanism of fipronil resistance in insects.

Full Text

Duke Authors

Cited Authors

  • Li, B-J; Wang, K-K; Chen, D-P; Yan, Y; Cai, X-L; Chen, H-M; Dong, K; Lin, F; Xu, H-H

Published Date

  • December 2021

Published In

Volume / Issue

  • 28 / 6

Start / End Page

  • 1721 - 1733

PubMed ID

  • 33442958

Electronic International Standard Serial Number (EISSN)

  • 1744-7917

International Standard Serial Number (ISSN)

  • 1672-9609

Digital Object Identifier (DOI)

  • 10.1111/1744-7917.12892


  • eng