• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Applied Microbiology >Association of Cry1Ac Toxin Resistance in Helicoverpa zea (Boddie) with Increased Alkaline Phosphatase Levels in the Midgut Lumen
【24h】

Association of Cry1Ac Toxin Resistance in Helicoverpa zea (Boddie) with Increased Alkaline Phosphatase Levels in the Midgut Lumen

机译：Helicoverpa zea（Boddie）中Cry1Ac毒素抗性与中肠管腔中碱性磷酸酶水平升高的关系

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Resistance to Bacillus thuringiensis Cry1Ac toxin was characterized in a population of Helicoverpa zea larvae previously shown not to have an alteration in toxin binding as the primary resistance mechanism to this toxin. Cry1Ac-selected larvae (AR1) were resistant to protoxins and toxins of Cry1Ab, Cry1Ac, and the corresponding modified proteins lacking helix α-1 (Cry1AbMod and Cry1AcMod). When comparing brush border membrane vesicles (BBMVs) prepared from susceptible (LC) and AR1 larval midguts, there were only negligible differences in overall Cry1Ac toxin binding, though AR1 had 18% reversible binding, in contrast to LC, in which all binding was irreversible. However, no differences were detected in Cry1Ac-induced pore formation activity in BBMVs from both strains. Enzymatic activities of two putative Cry1Ac receptors (aminopeptidase N [APN] and alkaline phosphatase [ALP]) were significantly reduced (2-fold and 3-fold, respectively) in BBMVs from AR1 compared to LC larvae. These reductions corresponded to reduced protein levels in midgut luminal contents only in the case of ALP, with an almost 10-fold increase in specific ALP activity in midgut fluids from AR1 compared to LC larvae. Partially purified H. zea ALP bound Cry1Ac toxin in ligand blots and competed with Cry1Ac toxin for BBMV binding. Based on these results, we suggest the existence of at least one mechanism of resistance to Cry1A toxins in H. zea involving binding of Cry1Ac toxin to an ALP receptor in the larval midgut lumen of resistant larvae.
机译：对苏云金芽孢杆菌Cry1Ac毒素的抗性的特征是以前显示没有将毒素结合改变作为对该毒素的主要抗性机制的Helicoverpa zea幼虫种群。 Cry1Ac选择的幼虫（AR1）对Cry1Ab，Cry1Ac和缺乏螺旋α-1的相应修饰蛋白（Cry1AbMod和Cry1AcMod）的毒素和毒素具有抗性。当比较由易感性（LC）和AR1幼虫中肠制备的刷状缘膜囊泡（BBMV）时，虽然与LC相比，AR1具有18％的可逆结合，而与所有结合均不可逆的LC相比，Cry1Ac毒素的整体结合仅可忽略不计。然而，在两种菌株的BBMV中，在Cry1Ac诱导的孔形成活性中均未发现差异。与LC幼虫相比，AR1的BBMV中两个推定的Cry1Ac受体（氨基肽酶N [APN]和碱性磷酸酶[ALP]）的酶活性显着降低（分别为2倍和3倍）。这些减少仅在ALP情况下对应于中肠腔内蛋白质含量的降低，与LC幼体相比，来自AR1的中肠液中比ALP活性几乎提高了10倍。部分纯化的玉米H. zea ALP在配体印迹中结合Cry1Ac毒素，并与Cry1Ac毒素竞争BBMV结合。基于这些结果，我们建议在玉米中至少存在一种对Cry1A毒素的抗性机制，其中涉及Cry1Ac毒素与抗性幼虫的幼体中肠腔中的ALP受体结合。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号