Docking-based generation of antibodies mimicking Cry1A/1B protein binding sites as potential insecticidal agents against diamondback moth (Plutella xylostella).
Docking-based generation of antibodies mimicking Cry1A/1B protein binding sites as potential insecticidal agents against diamondback moth (Plutella xylostella).
复制标题
DOI：
10.1002/ps.6499
复制
发表时间：
2021-06
影响因子：
4.1
通讯作者：
Yajing Xie;Chongxin Xu;M. Gao;Xiao Zhang;Lina Lu;Xiaodan Hu;Wei Chen;J. Jurat-Fuentes;Qing Zhu;Yuan Liu;Manman Lin;J. Zhong;Xianjin Liu
中科院分区：
文献类型：
--
作者：
Yajing Xie;Chongxin Xu;M. Gao;Xiao Zhang;Lina Lu;Xiaodan Hu;Wei Chen;J. Jurat-Fuentes;Qing Zhu;Yuan Liu;Manman Lin;J. Zhong;Xianjin Liu
来自苏云金芽孢杆菌（Bacillus thuringiensis）的杀虫Cry蛋白在生物农药和转基因作物中的广泛使用已经导致了实际田间抗性的情况，突出了对昆虫控制的新方法的需要。先前，我们描述了抗Cry 1Ab独特型抗体（B12-scFv）显示对稻纵卷叶螟（Cnaphalocrocis medinalis）幼虫的毒性，支持用于害虫防治的抗体的潜力。本研究的目的是产生针对小菜蛾（Plutella xylostella）幼虫的杀虫抗体。结果利用B12-scFv的三维结构和与小菜蛾Cry 1Ac受体碱性磷酸酶（ALP）的对接预测，设计了4个基因工程抗体（GEAb）。在这些GEAbs中，由两条轻链组成的GEAb-dVL抗体与Cry 1A和Cry 1B蛋白具有重叠的结合位点，并显示出对小菜蛾中肠刷状缘膜（BBM）蛋白的高结合亲和力。BBM中通过下拉测定鉴定为与GEAb-dVL结合的蛋白质包括ABC转运蛋白和V-ATP酶亚基A蛋白。尽管缺乏Cry 1A中负责孔形成的α-螺旋结构，但GEAb-dVL的摄入破坏了小菜蛾幼虫中肠上皮并导致毒性。在用GEAb-dVL处理后，肠细胞中的凋亡基因被激活。结论本研究描述了第一个通过模拟Cry蛋白靶向小菜蛾的杀虫GEAb。数据支持GEAb-dVL毒性与细胞内细胞死亡途径的激活相关，与Cry蛋白的孔形成相关毒性相反。本工作为设计新型杀虫抗体用于昆虫防治奠定了基础。
BACKGROUND Broad use of insecticidal Cry proteins from Bacillus thuringiensis in biopesticides and transgenic crops has resulted in cases of practical field resistance, highlighting the need for novel approaches to insect control. Previously we described an anti-Cry1Ab idiotypic-antibody (B12-scFv) displaying toxicity against rice leafroller (Cnaphalocrocis medinalis) larvae, supporting the potential of antibodies for pest control. The goal of the present study was to generate insecticidal antibodies against diamondback moth (Plutella xylostella) larvae. RESULTS Four genetically engineered antibodies (GEAbs) were designed in silico from B12-scFv using 3D structure and docking predictions to alkaline phosphatase (ALP) as a Cry1Ac receptor in P. xylostella. Among these GEAbs, the GEAb-dVL antibody consisting of two light chains had overlapping binding sites with Cry1A and Cry1B proteins and displayed high binding affinity to P. xylostella midgut brush border membrane (BBM) proteins. Proteins in BBM identified by pull-down assays as binding to GEAb-dVL included an ABC transporter and V-ATPase subunit A protein. Despite lacking the α-helical structures in Cry1A that are responsible for pore formation, ingestion of GEAb-dVL disrupted the P. xylostella larval midgut epithelium and resulted in toxicity. Apoptotic genes were activated in gut cells upon treatment with GEAb-dVL . CONCLUSION This study describes the first insecticidal GEAb targeting P. xylostella by mimicking Cry proteins. Data support that GEAb-dVL toxicity is associated to activation of intracellular cell death pathways, in contrast to pore-formation associated toxicity of Cry proteins. This work provides a foundation for the design of novel insecticidal antibodies for insect control.