Chen Lin, Wei Jizhen, Liu Chen, Zhang Wanna, Wang Bingjie, Niu LinLin, Liang Gemei
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
College of Plant Protection, Henan Agricultural University, Zhengzhou, China.
Front Physiol. 2018 Jun 19;9:745. doi: 10.3389/fphys.2018.00745. eCollection 2018.
A pyramid strategy combining the crystal (Cry) 1A and 2A toxins in (Bt) crops are active against many species of insects and nematode larvae. It has been widely used to delay pest adaption to genetically modified plants and broaden the insecticidal spectrum in many countries. Unfortunately, Cry2A can also bind with the specific receptor proteins of Cry1A. ATP-binding cassette (ABC) transporters can interact with Cry1A toxins as receptors in the insect midgut, and ABC transporter mutations result in resistance to Bt proteins. However, there is limited knowledge of the ABC transporters that specifically bind to Cry2Ab. Here, we cloned the gene in , which expressed at all larval stages and in nine different tissues. Expression levels were particularly high in fifth-instar larvae and Malpighian tubules. The two heterologously expressed transmembrane domain peptides could specifically bind to Cry2Ab with high affinity levels. Moreover, transfecting into the nine insect cell significantly increased its mortality when exposed to Cry2Ab , and silencing in by RNA interference significantly reduced the mortality of larvae exposed to Cry2Ab . Altogether current results suggest that serves as a functional receptor for Cry2Ab.
一种将苏云金芽孢杆菌(Bt)作物中的Cry1A和2A毒素结合的金字塔策略对多种昆虫和线虫幼虫具有活性。在许多国家,它已被广泛用于延缓害虫对转基因植物的适应性并拓宽杀虫谱。不幸的是,Cry2A也能与Cry1A的特定受体蛋白结合。ATP结合盒(ABC)转运蛋白可作为昆虫中肠中Cry1A毒素的受体相互作用,而ABC转运蛋白突变会导致对Bt蛋白产生抗性。然而,关于与Cry2Ab特异性结合的ABC转运蛋白的了解有限。在这里,我们克隆了棉铃虫中的该基因,其在所有幼虫阶段和九个不同组织中均有表达。在五龄幼虫和马氏管中的表达水平特别高。两种异源表达的跨膜结构域肽能以高亲和力水平特异性结合Cry2Ab。此外,将其转染到棉铃虫九种昆虫细胞中,当暴露于Cry2Ab时显著增加了其死亡率,而通过RNA干扰使棉铃虫中的该基因沉默则显著降低了暴露于Cry2Ab的幼虫的死亡率。总体而言,目前的结果表明该基因作为Cry2Ab的功能性受体。