Hubei Engineering Technology Center for Pest Forewarning and Management, College of Agriculture, Yangtze University, Jingzhou 434025, China; State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Pestic Biochem Physiol. 2023 Aug;194:105468. doi: 10.1016/j.pestbp.2023.105468. Epub 2023 May 18.
High level resistance for a variety of insecticides has emerged in Bemisia tabaci, a globally notorious insect. Neonicotinoid insecticides have been applied widely to control B. tabaci. Whether a differentially expressed gene CYP6DB3 discovered from transcriptome data of B. tabaci is involved in the resistance to neonicotinoid insecticides remains unclear. In the study, CYP6DB3 expression was significantly up-regulated in both thiamethoxam- and imidacloprid-resistant strains relative to the susceptive strains. We also found that CYP6DB3 expression was up-regulated after B. tabaci adults were exposed to thiamethoxam and imidacloprid. Moreover, knocking down CYP6DB3 expression via feeding corresponding dsRNA significantly reduced CYP6DB3 mRNA levels by 34.1%. Silencing CYP6DB3 expression increased the sensitivity of B. tabaci Q adults against both thiamethoxam and imidacloprid. Overexpression of CYP6DB3 gene reduced the toxicity of imidacloprid and thiamethoxam to transgenic D. melanogaster. In addition, metabolic studies showed that CYP6DB3 can metabolize 24.41% imidacloprid in vitro. Collectively, these results strongly support that CYP6DB3 plays an important role in the resistance of B. tabaci Q to imidacloprid and thiamethoxam. This work will facilitate a deeper insight into the part of cytochrome P450s in the evolution of insecticide resistance and provide a theoretical basis for the development of new integrated pest resistance management.
烟粉虱是一种全球知名的害虫，对多种杀虫剂已产生高水平抗性。新烟碱类杀虫剂已被广泛用于防治烟粉虱。然而，从烟粉虱转录组数据中发现的差异表达基因 CYP6DB3 是否参与了对新烟碱类杀虫剂的抗性尚不清楚。在本研究中，与敏感株相比，噻虫嗪和吡虫啉抗性株中 CYP6DB3 的表达均显著上调。我们还发现，烟粉虱成虫暴露于噻虫嗪和吡虫啉后 CYP6DB3 的表达上调。此外，通过喂食相应的 dsRNA 敲低 CYP6DB3 表达可使 CYP6DB3 mRNA 水平降低 34.1%。沉默 CYP6DB3 表达可显著提高烟粉虱 Q 代对噻虫嗪和吡虫啉的敏感性。过表达 CYP6DB3 基因降低了转基因 D. melanogaster 对吡虫啉和噻虫嗪的毒性。此外，代谢研究表明 CYP6DB3 可在体外代谢 24.41%的吡虫啉。综上所述，这些结果有力地支持 CYP6DB3 在烟粉虱 Q 代对吡虫啉和噻虫嗪的抗性中发挥重要作用。本研究将有助于深入了解细胞色素 P450s 在杀虫剂抗性进化中的作用，并为新的综合害虫抗性管理策略的制定提供理论依据。
