Loop replacements with gut-binding peptides in Cry1Ab domain II enhanced toxicity against the brown planthopper, Nilaparvata lugens (Stål).
Loop replacements with gut-binding peptides in Cry1Ab domain II enhanced toxicity against the brown planthopper, Nilaparvata lugens (Stål).
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Cry1Abdomain II 中肠道结合肽的环替换增强了对褐飞虱 Nilaparvata lugens(Stàl) 的毒性
DOI：
10.1038/srep20106
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发表时间：
2016-02-01
影响因子：
4.6
通讯作者：
Huang Z
中科院分区：
文献类型：
--
作者：
Shao E;Lin L;Chen C;Chen H;Zhuang H;Wu S;Sha L;Guan X;Huang Z
苏云金芽孢杆菌(Bt)Cry毒素已被广泛应用于害虫治理。然而，Cry毒素对吸液昆虫(半翅目)并不有效，这限制了Bt在害虫管理中的应用。为了将Bt毒素的杀虫谱扩展到褐飞虱(BPH)，我们用精选的BPH肠道结合肽(GBP)修饰了Cry1Ab的受体结合域。用两个Gbps(P_2S和P_1Z)分别取代了Cry1Ab结构域II的三个表面暴露环。生物测定结果表明，修饰毒素L2-P2S对褐飞虱若虫的毒力显著提高(~9 倍)。此外，取食L2-P2S的若虫对中肠细胞有一定的损伤作用。我们的结果表明，基于毒素-肠道相互作用对Cry毒素进行修饰可以拓宽Bt毒素的杀虫谱。该方法为开发具有新型杀虫活性的转基因作物和现有Bt转基因作物抗性的昆虫种群提供了另一种途径。
Bacillus thuringiensis (Bt) Cry toxins have been used widely in pest managements. However, Cry toxins are not effective against sap-sucking insects (Hemiptera), which limits the application of Bt for pest management. In order to extend the insecticidal spectrum of Bt toxins to the rice brown planthopper (BPH), Nilaparvata lugens, we modified Cry1Ab putative receptor binding domains with selected BPH gut-binding peptides (GBPs). Three surface exposed loops in the domain II of Cry1Ab were replaced with two GBPs (P2S and P1Z) respectively. Bioassay results showed that toxicity of modified toxin L2-P2S increased significantly (~9 folds) against BPH nymphs. In addition, damage of midgut cells was observed from the nymphs fed with L2-P2S. Our results indicate that modifying Cry toxins based on the toxin-gut interactions can broaden the insecticidal spectrum of Bt toxin. This method provides another approach for the development of transgenic crops with novel insecticidal activity against hemipteran insects and insect populations resistant to current Bt transgenic crops.