Potential for targeting the 26S proteasome non-ATPase regulatory subunit four gene NlPSMD4 for the control of Nilaparvata lugens
Author of the article:SHI Shu-Qi** YANG Jiang-Tao SHEN Bo-Yu HAO Pei-Ying*** YU Xiao-Ping***
Author's Workplace：Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou 310018, China
Key Words：Nilaparvata lugens; PSMD4; 26S proteasome; RNA interference; pest control
Abstract：[Aim] To investigate the function of the 26S proteasome non-ATPase regulatory subunit 4 (NlPSMD4), a core component of the UPS, in the growth, development and reproduction of Nilaparvata lugens, and evaluate its potential as a target for RNA interference (RNAi)-based control. [Methods] The spatiotemporal expression profiles of the NlPSMD4 gene were characterized using qRT-PCR. Gene silencing was performed by microinjecting dsRNA into nymphs and adults. Following RNAi treatment, mortality, fecundity, and egg hatching rates were systematically measured. Furthermore, the mRNA expression levels of vitellogenin (Vg), juvenile hormone acid methyltransferase (JHAMT) and ecdysone receptor (EcR) genes, were analyzed to elucidate the underlying molecular mechanisms. [Results] NlPSMD4 was expressed in all developmental stages and tissues, with the highest abundance observed in 2-day-old eggs and ovarian tissues. RNAi experiments demonstrated that silencing NlPSMD4 caused severe mortality; nymph survival dropped to 3.33% by day 11 post-treatment, and the survival rate of males and females declined to 4.00% and 4.17%, respectively, on days 10 and 14. RNAi treatment of both sexes (dsNlPSMD4♀ × dsNlPSMD4♂) caused the number of eggs to decrease to 62 per female, and the hatching rate to decrease to 25.65%. RNAi treatment of males only (dsGFP♀ × dsNlPSMD4♂) also significantly reduced the hatching rate of eggs to 41.93%. Gene expression analysis indicates that RNAi treatment disrupts hormonal and reproductive signaling homeostasis. mRNA expression of the JHAMT gene was significantly up-regulated in female adults, whereas that of the EcR gene was significantly up-regulated in males. Although the mRNA expression of the Vg gene in females surged 15-fold (20.07), the fecundity and hatching rates of eggs did not increase, but rather declined. [Conclusion] This study confirms that the NlPSMD4 gene plays a critical role in the survival and reproduction of the BPH. Loss of NlPSMD4 function results in significant lethality and sterility. Therefore, the NlPSMD4 gene is a promising target for the RNAi-based management of BPH.