获得高抗虫转双基因烟草

Highly Insect-resisant Transgenic Tobacco Plants Containing Both B. t and CpTI Genes

利用DNA合成仪人工合成了豇豆胰蛋白酶抑制剂(CpTI)的cDNA编码全序列。合成的基因经过克隆和序列分析后,克隆到植物高效表达载体上,并转化农杆菌,通过共转化的方法,将CpTI基因和经人工改造的苏云金芽孢杆菌(B.t)δ-内毒素基因共转化烟草,得到经PCR扩增并Southern-blotting验证的分别含有CpTI和B.t基因的植株以及同时含有CpTI和B.t基因的植株。利用棉铃虫幼虫进行的杀虫测试表明,转基因烟草和对照烟草相比具有明显的杀虫活性,同时转双基因的烟草和转单一基因的烟草相比具有增强的杀虫活性。

The cowpea trypsin inhibitor (CpTI) gene was synthesized according to its cDNA sequence using DNA Synthesizer and confirmed by DNA sequencing. The CpTI gene and modified Bacillus thuringiensis (B. t) δ-endotoxin gene were cotransformed to tobacco explants mediated by Agrobacterium tumefaciens. The integration of B. t and CpTI gene was confirmed by PCR and Southern hybridization. Three kinds of transgenic plants were obtained; (1) containing CpTI gene, (2) containing B. t gene, (3) Containing both CpTI and B. t genes. Bioassays showed that the transgenic plants were insectici-dal to the larvae of Heliothis armegra, and that the tobacco plants containing both genes had enhanced toxicity to larvae by comparison with plants containing only CpTI or B. t gene.