Lee Mi Kyong, Miles Paul, Chen Jeng-Shong
Syngenta Biotechnology, Inc., 3054 Cornwallis Road, Research Triangle Park, NC 27709, USA.
Biochem Biophys Res Commun. 2006 Jan 27;339(4):1043-7. doi: 10.1016/j.bbrc.2005.11.112. Epub 2005 Dec 1.
The binding properties of Vip3A, a new family of Bacillus thuringiensis insecticidal toxins, have been examined in the major cotton pests, Heliothis virescens and Helicoverpa zea. Vip3A bound specifically to brush border membrane vesicles (BBMV) prepared from both insect larval midguts. In order to examine the cross-resistance potential of Vip3A to the commercially available Cry1Ac and Cry2Ab2 toxins, the membrane binding site relationship among these toxins was investigated. Competition binding assays demonstrated that Vip3A does not inhibit the binding of either Cry1Ac or Cry2Ab2 and vice versa. BBMV protein blotting experiments showed that Vip3A does not bind to the known Cry1Ac receptors. These distinct binding properties and the unique protein sequence of Vip3A support its use as a novel insecticidal agent. This study indicates a very low cross-resistance potential between Vip3A and currently deployed Cry toxins and hence supports its use in an effective resistance management strategy in cotton.
苏云金芽孢杆菌新型杀虫毒素家族Vip3A的结合特性已在主要棉花害虫棉铃虫和烟青虫中进行了研究。Vip3A特异性结合从两种昆虫幼虫中肠制备的刷状缘膜囊泡（BBMV）。为了研究Vip3A对市售Cry1Ac和Cry2Ab2毒素的交叉抗性潜力，对这些毒素之间的膜结合位点关系进行了研究。竞争结合试验表明，Vip3A不抑制Cry1Ac或Cry2Ab2的结合，反之亦然。BBMV蛋白质印迹实验表明，Vip3A不与已知的Cry1Ac受体结合。Vip3A独特的结合特性和独特的蛋白质序列支持其作为一种新型杀虫剂使用。这项研究表明Vip3A与目前使用的Cry毒素之间的交叉抗性潜力非常低，因此支持其在棉花有效抗性管理策略中的应用。
