Nuclear Receptors as Lethal Targets in the White-Backed Planthopper via RNAi and Nanocarrier Delivery

Nuclear
receptors (NRs) are master regulators of insect ecdysis,
metamorphosis, and reproduction, ideal targets for eco-friendly pest
control. However, no comprehensive functional screening of the entire
NR family has been conducted in any of the insect species. Here, we
systematically identified 21 NR genes in the white-backed planthopper
(Sogatella furcifera, WBPH), a major
rice pest, and conducted an RNA interference (RNAi) screen via microinjection.
Five highly lethal targets (SfHR38-3, SfHR39, SfHR51, SfEG, and SfE75) were validated using a spray-induced and nanocarrier-delivered
gene silencing (SI-NDGS) system, causing severe ecdysis failure and
wing deformities. Transcriptomic analyses of previously uncharacterized SfEG and SfHR51 reveal that SfEG is an essential mediator of ecdysone signaling for epidermal development,
while SfHR51 integrates cellular proteostasis with
hormonal control of development. This study introduces a dual innovation:
potent species-specific RNAi targets and the functional characterization
of previously unknown NRs, establishing a mechanistic framework for
next-generation, eco-friendly biopesticides.