Kwa M S, de Maagd R A, Stiekema W J, Vlak J M, Bosch D
Department of Molecular Biology, Center for Plant Breeding and Reproduction Research-DLO (CPRO-DLO), Wageningen, 6700 AA, the Netherlands.
J Invertebr Pathol. 1998 Mar;71(2):121-7. doi: 10.1006/jipa.1997.4723.
A better understanding of the mode of action of Bacillus thuringiensis delta-endotoxins is needed to develop strategies which may prevent or slow down selection for resistance. We studied the effect of Cry1C on several different cultured insect cell lines by means of toxicity assays, ligand blotting, and toxin binding studies. A clear difference in sensitivity toward Cry1C between the insect cell lines was observed. Spodoptera frugiperda cell line Sf9 was most sensitive, whereas Spodoptera exigua cell lines SeUCR and SelZD2109 showed intermediate sensitivity. Mamestra brassicae (Mb0503) and Drosophila melanogaster (Dm1) cells were the least sensitive as compared to Sf9 cells. Ligand blot analysis of SDS-PAGE size-separated proteins showed that Cry1C specifically binds to a 40-kDa protein in Sf9, SeUCR, and SelZD2109 cells. Cry1Ab does not bind to this protein. The Cry1C-binding protein was not observed in Mb0503 and Dm1 cells, suggesting that the presence of the 40-kDa Cry1C-binding protein is correlated with sensitivity toward Cry1C.
为了制定可能预防或减缓抗性选择的策略，需要更好地了解苏云金芽孢杆菌δ-内毒素的作用模式。我们通过毒性测定、配体印迹和毒素结合研究，研究了Cry1C对几种不同培养昆虫细胞系的影响。观察到昆虫细胞系对Cry1C的敏感性存在明显差异。草地贪夜蛾细胞系Sf9最敏感，而甜菜夜蛾细胞系SeUCR和SelZD2109表现出中等敏感性。与Sf9细胞相比，甘蓝夜蛾（Mb0503）和黑腹果蝇（Dm1）细胞最不敏感。对SDS-PAGE大小分离的蛋白质进行配体印迹分析表明，Cry1C特异性结合Sf9、SeUCR和SelZD2109细胞中的一种40 kDa蛋白质。Cry1Ab不与该蛋白质结合。在Mb0503和Dm1细胞中未观察到Cry1C结合蛋白，这表明40 kDa Cry1C结合蛋白的存在与对Cry1C的敏感性相关。
