Adoxophyes orana is a major leafroller pest that damages fruit trees from Asia to Central Europe. The sex pheromone (SP) of A. orana comprises Z9-14:Ac, Z11-14:Ac, Z9-14:OH, Z11-14:OH, and E9-14: Ac. In this study, we characterized the ligand-binding properties of the AoraPBP3, combining experimental and computational approaches. RT-qPCR analyses demonstrated that AoraPBP3 was highly expressed in antennae of both sexes, as well as male wings, and with transcript levels significantly higher in male antennae than in female. Fluorescence competitive binding assays (FCBAs) revealed that AoraPBP3 exhibited the highest binding affinity for Z11-14:Ac and no detectable affinity for Z11-14:OH. Meanwhile, AoraPBP3 bound to six host plant volatiles (HPVs), exhibiting a strong preference for pear ester. Molecular dynamics (MD) simulations evaluating AoraPBP3 interaction with the five SP components showed that the AoraPBP3–Z11-14:Ac complex possessed the lowest binding energy. Conversely, a high RMSD was observed in the AoraPBP3–Z11-14:OH complex, which might be attributed to too short distances between AoraPBP3 and Z11-14:OH throughout the simulation trajectory. By clarifying the functional and structural binding mechanisms of AoraPBP3 toward SP components and host plant recognition, this work will provide valuable insights for developing targeted mating disruption strategies to manage A. orana populations in orchards.
Ren et al. (Sat,) studied this question.