Non-recessive Bt toxin resistance conferred by an intracellular cadherin mutation in field-selected populations of cotton bollworm.
Non-recessive Bt toxin resistance conferred by an intracellular cadherin mutation in field-selected populations of cotton bollworm.
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DOI：
10.1371/journal.pone.0053418
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发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Wu Y
中科院分区：
文献类型：
--
作者：
Zhang H;Wu S;Yang Y;Tabashnik BE;Wu Y
转基因作物生产的苏云金芽孢杆菌（Bt）毒素已被广泛种植，以控制害虫，但害虫的抗性进化可能会减少这种方法的好处。在毒素结合钙粘蛋白的胞外结构域的隐性突变，赋予抗性Bt毒素Cry1Ac破坏毒素结合先前已报道在三个主要的鳞翅目害虫，包括棉铃虫，棉铃虫。在这里，我们报告了一个新的等位基因，从棉铃虫与钙粘蛋白的细胞内结构域的缺失，是遗传连锁的非隐性抗性Cry1Ac。我们在中国北方Bt棉生产地的三个田间选择群体中发现了该等位基因。我们在异源细胞培养物中表达了四种类型的钙粘蛋白等位基因：敏感的，具有细胞内结构域突变的抗性的，以及具有和不具有突变的两种互补嵌合等位基因。用四种钙粘蛋白等位基因中的每一种转染的细胞结合Cry1Ac并被Cry1Ac杀死。然而，相对于用易感等位基因或缺乏胞内结构域突变的嵌合等位基因转染的细胞，用抗性等位基因或含有胞内结构域突变的嵌合等位基因转染的细胞对Cry1Ac较不敏感。这些结果表明，钙粘蛋白的细胞内结构域参与后结合事件，影响毒性的Cry1Ac。这一证据与Bt毒素作用模式的细胞信号模型提出的钙粘蛋白细胞内区域的重要作用是一致的。与以前报道的数据一起考虑，结果表明，孔形成和细胞信号通路有助于Bt毒素的功效。
Transgenic crops producing Bacillus thuringiensis (Bt) toxins have been planted widely to control insect pests, yet evolution of resistance by the pests can reduce the benefits of this approach. Recessive mutations in the extracellular domain of toxin-binding cadherin proteins that confer resistance to Bt toxin Cry1Ac by disrupting toxin binding have been reported previously in three major lepidopteran pests, including the cotton bollworm, Helicoverpa armigera. Here we report a novel allele from cotton bollworm with a deletion in the intracellular domain of cadherin that is genetically linked with non-recessive resistance to Cry1Ac. We discovered this allele in each of three field-selected populations we screened from northern China where Bt cotton producing Cry1Ac has been grown intensively. We expressed four types of cadherin alleles in heterologous cell cultures: susceptible, resistant with the intracellular domain mutation, and two complementary chimeric alleles with and without the mutation. Cells transfected with each of the four cadherin alleles bound Cry1Ac and were killed by Cry1Ac. However, relative to cells transfected with either the susceptible allele or the chimeric allele lacking the intracellular domain mutation, cells transfected with the resistant allele or the chimeric allele containing the intracellular domain mutation were less susceptible to Cry1Ac. These results suggest that the intracellular domain of cadherin is involved in post-binding events that affect toxicity of Cry1Ac. This evidence is consistent with the vital role of the intracellular region of cadherin proposed by the cell signaling model of the mode of action of Bt toxins. Considered together with previously reported data, the results suggest that both pore formation and cell signaling pathways contribute to the efficacy of Bt toxins.
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影响因子：
3.7
作者：
Gassmann AJ;Petzold-Maxwell JL;Keweshan RS;Dunbar MW
通讯作者：
Dunbar MW
影响因子：
3.7
作者：
Jurat-Fuentes JL;Karumbaiah L;Jakka SR;Ning C;Liu C;Wu K;Jackson J;Gould F;Blanco C;Portilla M;Perera O;Adang M
通讯作者：
Adang M
影响因子：
4.5
作者：
Gahan LJ;Pauchet Y;Vogel H;Heckel DG
通讯作者：
Heckel DG
影响因子：
2.8
作者：
Kranthi, KR;Dhawad, CS;Kranthi, S
通讯作者：
Kranthi, S
DOI：
10.1073/pnas.0831036100
发表时间：
2003-04-29
影响因子：
11.1
作者：
Morin, S;Biggs, RW;Tabashnik, BE
通讯作者：
Tabashnik, BE