The detoxification mediated by cytochrome P450 is always involved in insecticide resistance. Our previous studies have demonstrated that multiple P450 genes were overexpressed in the imidacloprid-resistant strain (SA-R) in Sitobion miscanthi. However, the characterization and transcriptional regulation of these related P450 genes were unknown. To understand the regulation mechanisms, the promoter of the two P450 genes, CYP6DD1 and CYP307A2, were obtained and analyzed under the induction of these two neonicotinoid insecticides, indicating that the transcript levels of CYP6DD1 and CYP307A2 were significantly induced by both imidacloprid and thiamethoxam. Furthermore, the overexpression in the imidacloprid-resistant strain (SA-R), and the increased sensitivity of S. miscanthi to these two neonicotinoid insecticides after knockdown of CYP6DD1 and CYP307A2 were all observed, suggesting that CYP6DD1 and CYP307A2 could be involved in the resistance of S. miscanthi to some neonicotinoids. Subsequently, we examined the regulatory mechanism of CYP6DD1 and CYP307A2 based on the transcriptional level. The promoter regions from −610 to +182 bp, and from −292 to +236 bp were critical for transcription activities of CYP6DD1 and CYP307A2, respectively. The cis-elements between −368 and −244 bp of CYP6DD1, and between −128 and + 144 bp of CYP307A2, were identified as insecticide responsive regions. The binding site of a potential nuclear factor erythroid 2-related factor 2 (Nrf2) was found with a conserved sequence motif 5′-CA/TCAGCAT/C-3′. It is of great significance to understand this regulatory mechanism of P450 expression in the resistance of Sitobion miscanthi to neonicotinoids.

细胞色素 P450 介导的解毒作用始终与杀虫剂抗性有关。我们之前的研究表明，在Sitobion miscanthi的吡虫啉抗性菌株 (SA-R) 中，多个 P450 基因过度表达。然而，这些相关 P450 基因的特征和转录调控是未知的。为了解调控机制，在这两种新烟碱类杀虫剂的诱导下，获得并分析了两个P450基因的启动子CYP6DD1和CYP307A2，表明CYP6DD1和CYP307A2的转录水平吡虫啉和噻虫嗪均显着诱导。此外，在吡虫啉抗性菌株（SA-R）中的过度表达，以及在敲除 CYP6DD1和CYP307A2后，芒草对这两种新烟碱类杀虫剂的敏感性增加，均表明CYP6DD1和CYP307A2可能参与抗性的S. miscanthi一些新烟碱类。随后，我们根据转录水平检查了CYP6DD1和CYP307A2的调控机制。-610 至 +182 bp 和 -292 至 +236 bp 的启动子区域对转录活性至关重要分别为CYP6DD1和CYP307A2。CYP6DD1 的-368 和-244 bp 之间以及CYP307A2 的-128 和+ 144 bp之间的顺式元件被鉴定为杀虫剂响应区域。发现具有潜在的序列基序5'-CA / TCAGCAT / C-3'的潜在核因子红系2相关因子2（Nrf2）的结合位点。了解 P450 表达的这种调控机制在Sitobion miscanthi对新烟碱类药物的抗性中具有重要意义。