Knockdown of Clavesin family genes NlClvs1l, NlClvs1t, and NlClvs2l in Nilaparvata lugens reveals their potential as novel targets for pest control strategies.

The brown planthopper (BPH) Nilaparvata lugens is one of the most destructive pests of rice, and its management has primarily relied on chemical insecticides. Currently, the chemical management of BPH is facing challenges due to the development of pesticide resistance. RNA interference (RNAi) provides attractive alternative to chemical insecticides, provided that suitable target genes are identified. Clavesin (clathrin vesicle-associated Sec14 protein) proteins are involved in multiple biological processes, including endocytosis, oxidative stress response, and the regulation of lysosome morphology, among others. However, the potential of these Clavesins in controlling BPH remains unclear. In this study, three Clavesin genes in BPH were identified and their potential for pest control was evaluated. qRT-PCR results revealed that the mRNA expression levels of NlClvs1l and NlClvs2l were higher in male adults than in female adults, while the expression level of the NlClvs1t gene was much higher in eggs. All three Clavesin genes exhibited high expression levels in the head and moderate expression levels in the testis. RNAi-mediated knockdown of Clvs1l, Clvs1t, and Clvs2l reduced the survival rates to 13.3 %, 7.8 % and 41.1 %, respectively, at day 10 post dsRNA injection. The reproductive capacity of the groups treated with dsClvs1l, dsClvs1t, and dsClvs2l decreased compared to that of the control group (dsGFP♂ × dsGFP♀). Notably, in the dsClvs1t♂ × dsGFP♀ group, the number of offspring was significantly decreased by 62.7 %. In addition, RNAi of Clvs1l, Clvs1t, and Clvs2l also influenced the development of both testis and ovaries. Overall, the Clavesin gene plays a crucial role in cellular membrane vesicle trafficking. RNA interference targeting the Clavesin gene, particularly NlClvs1t, significantly impairs membrane vesicle transport, thereby disrupting nutrient absorption and metabolism in brown planthoppers and reducing their survival rate. Additionally, by inhibiting the synthesis of vitellogenin, RNAi of NlClvs1t negatively affects oocyte quantity and quality, ultimately leading to a decline in offspring production. Therefore, these three Clavesin genes are essential for the survival and fecundity of BPH and represent promising candidates for the development of novel pest control strategies.