摘要
来源于丁香假单孢杆菌 ( Pseudomonas syringae subsp.savastanoi)的吲哚乙酰胺赖氨酸酯合成酶基因 ( iaa L )与来自水稻 ( Oryza sativa)的在花器官中具有高水平表达的启动子 ( Rch1 0 )融合后导入烟草( N icotiana tabacum)。在转基因烟草中研究了这种嵌合基因的表达特性 ,并测定了各个器官内源生长素的水平。结果表明 :Rch1 0启动子能引导 iaa L基因在转基因植株的幼嫩花序、花器官及幼嫩果实中表达 ,并导致了各器官内源生长素水平不同程度的降低。转基因植株当代的花序或花器官的发育出现了明显的表型变异 :开花后顶端优势减弱、花序正常发育受阻、果实发育不良等。这些 Rch1 0 - iaa L的转基因植株可为进一步研究
The indoleacetic acid lysine synthetase (iaaL) gene of Pseudomonas syringae subsp. savastanoi was fused to a rice Rch10 promoter and introduced into tobacco plants. The expression pattern of this chimeric Rch10 iaaL gene in the transgenic plants was studied, and the endogenous levels of indoleacetic acid (IAA) were assayed with the high performance liquid chromatography (HPLC) method. The results showed that the Rch10 promoter could direct the high level expression of the iaaL gene in young inflorescences, fully bloomed flowers, and immature fruits, resulted in a decrease of the IAA levels by 32%～82%. The transgenic plants displayed decreased apical dominance, enlongated stamens, abnormal inflorescences and fruits. The transgenic plant pYL614 T14, in which the endogenous IAA levels in inflorescences were reduced by 82%, displayed extremely abnormal inflorescence with only two flowers and a much higher potential of vegetative growth than that of the controls after flowering. These Rch10 iaaL gene transgenic tobacco plants would provide valuable materials for further studies of physiological functions of IAA in reproductive development.
基金
植物分子遗传国家重点实验室资助课题
关键词
烟草
花器官
特异表达启动子
转基因烟草
iaaL
Floral specific promoter
IAA lysine synthetase gene
Transgenic tobacco
Flower development
