Silencing OdfoP-gp1 and OdfoP-gp3 with dsRNA increased the lethality of the nonsteroidal ecdysone agonist RH-5849 against Odontotermes formosanus (Shiraki)

Abstract

Odontotermes formosanus (Shiraki) is a highly damaging social insect that causes significant economic losses. Insect growth regulators (IGRs) are efficient and environmentally friendly insecticides. 1,2-dibenzoyl-1-tert-butylhydrazine (RH-5849), a nonsteroidal ecdysone agonist of IGR, is highly effective in controlling various insect species. In this study, the toxicity of RH-5849 against O. formosanus was assessed. To investigate whether ATP-binding cassette (ABC) transporter proteins, detoxification enzymes, play crucial roles in the defense of O. formosanus against RH-5849, transcriptome sequencing was conducted in O. formosanus. Through RNA sequencing, 27 ABC transporter protein genes were identified, 23 of which were significantly upregulated after O. formosanus was exposed to RH-5849, especially two P-glycoprotein genes, OdfoP-gp1 and OdfoP-gp3, whose expression levels were the most significantly upregulated, at 5.79 and 5.56, respectively. Furthermore, using dsRNAs to interfere with the expression of OdfoP-gp1 and OdfoP-gp3, we found that the maximum interference efficiency was achieved at 24 h, with efficiencies of 85.30 % and 59.59 %, respectively. Based on these findings, dsRNA was coupled with RH-5849, and the results indicated that the lethality of RH-5849 against O. formosanus significantly increased following dsRNA interference. Overall, the lethality of RH-5849 significantly increased following dsRNA interference, suggesting that ABC transporter proteins, especially P-glycoproteins, play a crucial role in the defense of O. formosanus against RH-5849. This study provides a new strategy for termite control through the combination of dsRNA and IGR.