Insect Ryanodine Receptor: Distinct but Coupled Insecticide Binding Sites for [N‑C³H₃]Chlorantraniliprole, Flubendiamide, and [³H]Ryanodine

Radiolabeled anthranilic diamide insecticide [N-C³H₃]­chlorantraniliprole was synthesized at high specific activity. It was compared with phthalic diamide insecticide flubendiamide and [³H]­ryanodine in radioligand binding studies with house fly muscle membranes to provide the first direct evidence with a native insect ryanodine receptor that the major anthranilic and phthalic diamide insecticides bind at different allosterically coupled sites, i.e., there are three distinct Ca²⁺-release channel targets for insecticide action.