Abstract:

A chimeric gene, Bt29K, composed of coding sequences of activated Cry1Ac insecticidal protein and an endoplasm reticulum_retarding signal peptide, was synthesized. A plant expression vector containing two expression cassettes for the Bt29K and API_B genes was constructed. These two insect_resistant genes were transferred into two cotton (Gossypium hirsutum L.) varieties (or lines) via Agrobacterium_mediated transformation and nine homozygous transgenic cotton lines showing a mortality of 90.0%-99.7% to cotton ballworm (Heliothis armigera) larvae and good agronomic traits were selected through six generations. Molecular biology analysis revealed that one or two copies of the insecticidal protein genes were integrated into the transgenic cotton genome and activated Cry1Acand API_B protein expression was at a level of 0.17% and 0.09% of the total soluble protein in the transgenic cotton leaves, respectively. Comparison of the insect_resistance of the homozygous lines expressing the activated chimeric Cry1Ac and API_B with that expressing Cry1Ac only revealed that the insect_resistance of the former is apparently higher than the latter. These results also indicate that the strategy to construct a plant expression vector expressing two different insect_resistant genes reported here is reasonable.

转Cry1Ac活性杀虫蛋白及慈菇蛋白酶抑制剂B基因的棉花
郭洪年¹  吴家和²   陈晓英¹   罗晓丽²  卢 睿¹   石跃进²  秦红敏¹  肖娟丽²  田颖川^1*
（1. 中国科学院微生物研究所，北京 100080；2. 山西省农业科学院棉花研究所，运城 044000)
摘要： 根据植物基因的结构特征，合成了Cry1Ac 活性杀虫蛋白的编码序列并与内质网定位肽编码序列组成嵌合杀虫蛋白基因Bt29K。构建了含Bt29K基因及慈菇蛋白酶抑制剂[（ 8<)B$）基因表达框的双抗虫基因植物表达载
体。通过根癌土壤杆菌（830.@1-%+0"92 %92+I1-"+#6（>W+2. /2 \A1,0/,H）-A,, =[‘bbOb）介导转化了棉花（J.66?’"92 5"069B
%92 =*）的两个生产品种（系）。根据抗棉铃虫（*+,".%5"6 102"3+01）试验及农艺性状的观察调查结果，经N 代筛选，获得
了抗棉铃虫FO*Og h FF*)g且农艺性状优良的F 个双价抗虫棉纯合品系。分子生物学分析结果表明，两个抗虫基
因在棉花基因组中的插入拷贝数为’ 个或$ 个。活性-8J’‘9 和‘?G<[ 蛋白在转基因抗虫棉株系中的表达量分别约
占总可溶性蛋白的O*’)g和O*OFg。对双抗纯合系植株及仅转$% 基因的棉花纯合系抗虫性检测结果表明前者的
抗虫性明显高于后者，因此推断本研究采用的双抗虫基因表达载体构建策略是合理的。
关键词： 合成的嵌合&0?C8- 基因；慈菇蛋白酶抑制剂基因；抗虫转基因棉花
中图分类号：UFb&*$ 文献标识码：‘ 文章编号：OV))<)bFN（$OO&）O’<O’OX<ON
收稿日期：$OO’<’$<$F 接收日期：$OO$<OV<’$
基金项目：国家高技术研究和发展计划（XN&）项目（@’)<O’<O’；$OO’‘‘$’$O)’）。
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