杨树皮储藏蛋白基因启动子的克隆和功能研究

杨树树皮储藏蛋白BSP是类似种子储藏蛋白的氮素储藏物 ,冬季在韧皮部薄壁细胞中大量积累 ,是落叶树氮代谢中的重要成分。为了研究BSP基因启动子在转基因植物中的表达特性 ,探索其在植物基因工程研究中潜在的应用价值 ,我们用PCR方法从美洲黑杨基因组中DNA扩增得到了BSA启动子片段。与GUS基因融合构建中间载体后 ,转化烟草 ,获得了一批PCR检测为阳性的转化再生植株。经GUS组织化学检测 ,发现若干转基因烟草的茎和叶柄韧皮部以及叶脉都呈GUS染色阳性 ,初步证明杨树BSP基因启动子确有韧皮部表达特性 ,可介导GUS基因在转基因烟草韧皮部特异表达。

CLONING OF A PROMOTER FRAGMENT OF BARK STORAGE PROTEIN GENE FROM POPULUS DELTOIDES AND ITS FUNCTION IN TRANSGENIC TOBACCO PLANTS

Bark storage protein(BSP) of poplar, a nitrogen reserve similar to seed storage protein, plays an important role in the nitrogen metabolism of deciduous trees. They present in large quantities in the phloem parenchyma cells in winter. In order to learn the expression pattern of BSP gene promoter in transgenic plants, and to explore its potential application in plant genetic engineering for phloem specific expression of interested genes. BSP gene promoter fragment was amplified by PCR method from Populus deltoides genome DNA. Intermediate vector was constructed by inserting the promoter sequence upstream of GUS gene in pBI121, resulting in the replacement of the original CaMV 35?S promoter by the BSP promoter. Regenerated tobacco plants obtained by transformation were analyzed by PCR to select the putative transgenic plans. Histochemical localization of GUS activity indicated that BSP promoter could confer a phloem specific expression of GUS gene.