鳞翅目昆虫中肠Bt杀虫蛋白受体研究进展

Research progress on Bacillus thuringiensis insecticidal protein receptors in lepidopteran midgut

杀虫晶体蛋白(insecticidal crystal proteins,ICPs;含有Cry和Cyt 2大家族)和营养期杀虫蛋白(vegetative insecticidal proteins,Vips)等Bt杀虫蛋白可有效防治鳞翅目害虫,其中Cry应用最广泛。然而,一些地区的鳞翅目害虫已对Bt杀虫蛋白产生了抗性。目前,普遍认为鳞翅目昆虫中肠受体与Bt杀虫蛋白结合能力的改变是导致其对Bt杀虫蛋白产生抗性的最主要因素。在鳞翅目昆虫中,Cry受体是研究得最为透彻的Bt受体,已经被证实的有氨肽酶N、钙黏蛋白、碱性磷酸酶和ABC转运蛋白等。Vips杀虫蛋白类与鳞翅目昆虫中肠受体的结合方式与Cry杀虫蛋白相似,但结合位点与Cry杀虫蛋白不同。本文从结构特点、作用机制及不同鳞翅目昆虫间的表达差异等角度对以上4种鳞翅目昆虫中肠Bt受体进行了综述,并提出如下展望:(1)以棉铃虫或小菜蛾等鳞翅目昆虫为农业害虫模式生物进行深入研究,阐明其对Bt杀虫蛋白产生抗性的机制,为研究其他鳞翅目农业害虫对Bt杀虫蛋白产生抗性的机制提供理论借鉴;(2)鉴于在不同鳞翅目昆虫间,中肠Bt受体与Bt杀虫蛋白结合存在差异,且同一Bt杀虫蛋白与鳞翅目昆虫Bt受体并不专一性结合,Bt杀虫蛋白多基因组合策略是较为有效的田间鳞翅目昆虫防治策略,是今后一段时间内Bt杀虫蛋白应用的发展方向。

Insecticidal crystal proteins of two major families,Cry and Cyt,vegetative insecticidal proteins and other Bacillus thuringiensis(Bt)insecticidal proteins are effective for controlling lepidopteran pests,with Cry as the most widely used Bt insecticidal protein.However,lepidopteran pests in some areas have developed resistance to Bt insecticidal proteins.A change in the ability of lepidopteran midgut receptors to bind to Bt insecticidal proteins is thought to be the most important factor leading to their resistance to Bt insecticidal proteins.Among lepidopteran insects,Cry receptors are the most widely studied,including aminopeptidase N,cadherin,alkaline phosphatase,and the ATP-binding cassette transporter.The binding modes of vegetative insecticidal proteins are similar to those of Cry insecticidal proteins,but the binding sites differ from those.This review mainly describes the Bt insecticidal protein receptors in the midguts of lepidopteran insects based on the structural characteristics,mechanisms of action,and differences in expression,and proposes the following:(1)Helicoverpa armigera and Plutella xylostella can be used as models of agricultural insect pests to clarify the mechanisms of their resistance to Bt insecticidal proteins,providing theoretical references for the resistance mechanisms;(2)As the midgut receptors of Bt insecticidal proteins may differ and a Bt insecticidal protein may bind to more than one receptor,the multi-gene combination strategy of Bt insecticidal proteins is a more effective method and development direction for Bt insecticidal protein application.