【摘要】 来自农杆菌（Ａｇｒｏｂａｃｔｅｒｉｕｍ ｔｕｍ ｅｆａｃｉｅｎｓ）的细胞分裂素生物合成基因——异戊烯基转移酶基因（ｉｐｔ）与矮牵牛（Ｐｅｔｕｎｉａ ｈｙｂｒｉｄａ Ｖｉｌｍ ．）中的磷酸核酮糖羧化酶小亚基启动子（ＳＳＵ）融合后转入烟草（Ｎｉｃｏｔｉａｎａ ｔａｂａｃｕｍ Ｌ．）。在转基因烟草中研究了这种嵌合基因的特异性表达，并且测定了内源细胞分裂素水平的变化。结果表明，矮牵牛的ＳＳＵ 启动子能够特异性地控制ｉｐｔ基因在烟草中的表达更多还原

【Abstract】 The cytokinin biosynthetic gene, isopentenyl transferase (ipt) gene of Agrobacterium tumefaciens was fused to a petunia ribulose bisphosphate carboxylase small subunit (SSU301) promoter and introduced into tobacco plants. The expression pattern of this chimeric SSU ipt gene was studied in the transgenic plants, and the endogenous levels of cytokinins were determined. It was revealed that ipt mRNA level was increased in light cultured transgenic tobacco tissues, but was undetectable in dark cultured condition. The levels of zeatin and zeatin riboside in the transgenic tissues in light increased about 10 times as compared with the tissues in dark. The results show that the petunia SSU301 promoter can specifically direct the expression of the ipt gene in the transgenic tobacco. These SSU ipt gene transgenic tobacco plants will provide valuable materials for studies of cytokinin′s functions in phytosynthetic tissues and in the light related physiological processes.更多还原