TRP Channels in Insect Stretch Receptors as Insecticide Targets

• Two commercial insecticides disrupt insect coordination and hearing
• The insecticides silence stretch receptors that co-express the TRPs Iav and Nan
• Nan and Iav together confer cellular insecticide responses in vivo and in vitro
• The two insecticides are specific agonists of Nan-Iav complexes

SummaryDefining the molecular targets of insecticides is crucial for assessing their selectivity and potential impact on environment and health. Two commercial insecticides are now shown to target a transient receptor potential (TRP) ion channel complex that is unique to insect stretch receptor cells. Pymetrozine and pyrifluquinazon disturbed Drosophila coordination and hearing by acting on chordotonal stretch receptor neurons. This action required the two TRPs Nanchung (Nan) and Inactive (Iav), which co-occur exclusively within these cells. Nan and Iav together sufficed to confer cellular insecticide responses in vivo and in vitro, and the two insecticides were identified as specific agonists of Nan-Iav complexes that, by promoting cellular calcium influx, silence the stretch receptor cells. This establishes TRPs as insecticide targets and defines specific agonists of insect TRPs. It also shows that TRPs can render insecticides cell-type selective and puts forward TRP targets to reduce side effects on non-target species.