Wei Jizhen, Yao Xue, Yang Shuo, Liu Shaokai, Zhou Shuai, Cen Junjuan, Liu Xiaoguang, Du Mengfang, Tang Qingbo, An Shiheng
State Key Laboratory of Wheat and Maize Crop Science, College of Plant Protection, Henan Agricultural University, Zhengzhou, China.
Bureau of Agriculture and Rural Affairs of Qixian, Kaifeng, China.
Front Microbiol. 2021 Feb 11;12:634619. doi: 10.3389/fmicb.2021.634619. eCollection 2021.
Insect resistance to (Bt) insecticidal proteins has rapidly evolved with the expansion of the planting area of transgenic Bt crops. Pyramiding RNA interference (RNAi) and Bt in crops is urgently needed to counter the rapid increase in pest resistance. The ideal "pyramid" strategy simultaneously targets different action pathways that exert synergetic effects on each other. Here, we identified a dephosphatase, namely, calcineurin (HaCAN), which might enhance the insecticidal activity of Cry1Ac against by regulating immune gene expression via dephosphatase activity, but not by acting as a receptor. Notably, blocking enzyme activity or knocking down endogenous HaCAN significantly promoted the enhancement in Cry1Ac toxicity to insect larvae and cells. Correspondingly, the increase in HaCAN activity reduced the cytotoxicity of Cry1Ac as shown by the heterologous expression of HaCAN. Our results provide a probable that HaCAN is an important candidate gene for pyramiding RNAi and Cry1Ac crops to control cotton bollworm.
随着转基因抗虫棉种植面积的扩大，昆虫对苏云金芽孢杆菌（Bt）杀虫蛋白的抗性迅速进化。迫切需要在作物中构建RNA干扰（RNAi）和Bt基因的复合性状来应对害虫抗性的快速增加。理想的“复合性状”策略同时针对不同的作用途径，这些途径相互之间发挥协同作用。在此，我们鉴定出一种磷酸酶，即钙调神经磷酸酶（HaCAN），它可能通过磷酸酶活性调节免疫基因表达，而不是作为受体，来增强Cry1Ac对棉铃虫的杀虫活性。值得注意的是，阻断酶活性或敲低内源性HaCAN显著促进了Cry1Ac对昆虫幼虫和细胞毒性的增强。相应地，如通过HaCAN的异源表达所示，HaCAN活性的增加降低了Cry1Ac的细胞毒性。我们的结果提供了一种可能性，即HaCAN是构建RNAi和Cry1Ac复合性状作物以防治棉铃虫的重要候选基因。
