【摘要】 将柽柳(Tamarix.sp)金属硫蛋白基因(MT1)插入到植物表达载体pBI121,利用根癌农杆菌(Agrobactrium tumefaciens)介导法将MT1导入烟草(Nicotiana tobacum)基因组。对转基因T1植株的卡那霉素抗性分析表明,整合到烟草基因组的外源基因多为单拷贝基因,也有少数为多拷贝基因。对具有卡那霉素抗性的转基因植株进行PCR-Southern检测和Northern杂交分析表明,外源MT1基因已整合到烟草基因组,并且得到了正确表达。转基因植株对重金属镉的抗性比对照显著提高,表现为转基因植株的株高和鲜重均明显优于非转基因株系。更多还原

【Abstract】 A metallothionein gene from Tamarix sp was directionally cloned into the pBI121 binary vector, in place of the XbaⅠ-SacⅠGUS cassette. The Cauliflower mosaic virus (CaMV) 35S promoter/-nopalin synthase(nos) terminator system and kanamycin resistant gene NPTⅡ (neomycin phosphotransfers II) were used for these constitutive expression systems. The plasmid was then introduced into Agrobacterium tumefaciens (strain EHA105) by electroporation. Tobacco (Nicotiana tobacum) primary transformants were produced by leaf disc transformation. Kanamycin tolerance analysis of T1 generation of transgenic tobacco showed that most of them had 3:1 separation ratios, and only few had 15:1 separate ratios. This indicated that most transgenic plants had one copy of the exogenous gene in tobacco transformants. Southern and Northern hybridization indicated that exogenous gene has been integrated into the transgenic tobacco plants, and correctly expressed under the control of 35S promoter. Transgenic tobacco plants showed a better tolerant ability to cadmium than that of non-transformant.更多还原