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将全长３．５ｋｂ的Ｂｔ基因３’端缺失，得到长为２．１ｋｂ、１．８ｋｂ的基因。分别将这３个长度 （１．８ｋｂ２．１ｋｂ、３．５ｋｂ）的基因置于水稻叶绿体ｐｓｂＡ基因的启动于和终止子调控之下，并与选择 标记基因ａａｄＡ（编码氨基糖苷－３’－腺苷酸转移酶，具壮观霉素抗性）表达盒相连５以烟草叶绿 体基因ｔｒｎＨ－ｐｓｂＡ－ｔｒｎＫ为同源片段，构建成叶绿体转化载体ｐＢＴ３、ｐＢＴ８和ｐＢＴ２２。用基因枪 把Ｂｔ基因导入烟草叶绿体中，以壮观霉素筛选，获得转化再生植株。经Ｓｏｕｔｈｅｒｎ、Ｗｅｓｔｅｒｎ检测 分析证明Ｂｔ基因已整合进入烟草叶绿体基因组中并得到表达。且子代呈现壮观霉素抗性，即 外源基因得到稳定的遗传。利用转基因植株叶片对棉铃虫进行杀虫实验，有些转化植株表现 出较强的抗虫性。总体上来说，转Ｂｔ全长基因的烟草植株，其杀虫效果最好，其余两种差异不 大。首次报道将Ｂｔ基因成功转入高等植物叶绿体并获得表达。
The 3 ’end of the 3.5 kb Bt gene was deleted, resulting in a 2.1 kb, 1.8 kb gene. These three genes (1.8kb2.1kb, 3.5kb) were placed under the control of promoter and terminator of psbA gene in rice chloroplast and were compared with the selectable marker genes aadA (encoding aminoglycoside-3’-gland Glycosyltransferase with spectinomycin resistance) expression cassette. 5 The chloroplast transformation vectors pBT3, pBT8 and pBT22 were constructed using the tobacco chloroplast gene trnH-psbA-trnK as a homologous fragment. Bt gene was introduced into tobacco chloroplasts by gene gun and transformed into regenerated plants by screening with spectinomycin. Southern and Western analysis showed that the Bt gene was integrated into tobacco chloroplast genome and expressed. And the progeny showed spectinomycin resistance, that is, the exogenous gene was stably inherited. Helicoverpa armigera was insecticidally tested with the leaves of transgenic plants, and some of the transformed plants showed strong insect resistance. Generally speaking, the tobacco plants transformed with the full-length Bt gene have the best insecticidal effect and the other two have little difference. It was first reported that the Bt gene was successfully transferred into higher plant chloroplast and expressed.