Structural basis for diamide modulation of ryanodine receptor

Nat Chem Biol. 2020 Nov;16(11):1246-1254. doi: 10.1038/s41589-020-0627-5. Epub 2020 Aug 17.

Abstract

The diamide insecticide class is one of the top-selling insecticides globally. They are used to control a wide range of pests by targeting their ryanodine receptors (RyRs). Here, we report the highest-resolution cryo-electron microscopy (cryo-EM) structure of RyR1 in the open state, in complex with the anthranilic diamide chlorantraniliprole (CHL). The 3.2-Å local resolution map facilitates unambiguous assignment of the CHL binding site. The molecule induces a conformational change by affecting the S4-S5 linker, triggering channel opening. The binding site is further corroborated by mutagenesis data, which reveal how diamide insecticides are selective to the Lepidoptera group of insects over honeybee or mammalian RyRs. Our data reveal that several pests have developed resistance via two mechanisms, steric hindrance and loss of contact. Our results provide a foundation for the development of highly selective pesticides aimed at overcoming resistance and therapeutic molecules to treat human myopathies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Bees
  • Binding Sites
  • Calcium Channel Blockers / chemistry
  • Calcium Channel Blockers / metabolism*
  • Calcium Channel Blockers / pharmacology
  • Cryoelectron Microscopy
  • Diamide / chemistry*
  • Drug Development
  • Drug Resistance
  • Insecticides / chemistry
  • Insecticides / metabolism*
  • Insecticides / pharmacology
  • Lepidoptera
  • Models, Molecular
  • Mutagenesis / physiology
  • Protein Binding
  • Protein Conformation
  • Ryanodine Receptor Calcium Release Channel / metabolism*
  • Signal Transduction
  • Substrate Specificity
  • ortho-Aminobenzoates / chemistry
  • ortho-Aminobenzoates / metabolism*
  • ortho-Aminobenzoates / pharmacology

Substances

  • Calcium Channel Blockers
  • Insecticides
  • Ryanodine Receptor Calcium Release Channel
  • ortho-Aminobenzoates
  • Diamide
  • chlorantranilipole

Grants and funding