Heckel David G
Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, D-07745 Jena, Germany.
Insects. 2021 Apr 28;12(5):389. doi: 10.3390/insects12050389.
In the last ten years, ABC transporters have emerged as unexpected yet significant contributors to pest resistance to insecticidal pore-forming proteins from (Bt). Evidence includes the presence of mutations in resistant insects, heterologous expression to probe interactions with the three-domain Cry toxins, and CRISPR/Cas9 knockouts. Yet the mechanisms by which ABC transporters facilitate pore formation remain obscure. The three major classes of Cry toxins used in agriculture have been found to target the three major classes of ABC transporters, which requires a mechanistic explanation. Many other families of bacterial pore-forming toxins exhibit conformational changes in their mode of action, which are not yet described for the Cry toxins. Three-dimensional structures of the relevant ABC transporters, the multimeric pore in the membrane, and other proteins that assist in the process are required to test the hypothesis that the ATP-switch mechanism provides a motive force that drives Cry toxins into the membrane. Knowledge of the mechanism of pore insertion will be required to combat the resistance that is now evolving in field populations of insects, including noctuids.
在过去十年中，ABC转运蛋白已成为害虫对来自苏云金芽孢杆菌（Bt）的杀虫成孔蛋白产生抗性的意外但重要的因素。证据包括抗性昆虫中存在突变、用于探究与三结构域Cry毒素相互作用的异源表达，以及CRISPR/Cas9基因敲除。然而，ABC转运蛋白促进孔形成的机制仍不清楚。已发现农业中使用的三大类Cry毒素靶向三大类ABC转运蛋白，这需要一个机理解释。许多其他细菌成孔毒素家族在其作用模式中表现出构象变化，而Cry毒素尚未有相关描述。需要相关ABC转运蛋白的三维结构、膜中的多聚体孔以及其他协助该过程的蛋白质，以检验ATP开关机制提供驱动力将Cry毒素驱动到膜中的假说。为了应对包括夜蛾科昆虫在内的田间昆虫种群正在产生的抗性，将需要了解孔插入的机制。
