Producing Transformed Maize with Dehydration-Responsive Transcription Factor CBF4 Gene

The CBF4 gene was cloned from Arabidopsis thaliana and driven by the promoter of preceding stress responsive gene rd29A. By means of biolistic bombardment, this gene was transferred into immature embryo and embryogenic callus of several elite maize (Zea mays L.) inbred lines via expression vector pBAC146. A total of 64 transgenic plants were obtained following callus induction, resistance selection, differentiation, and plant regeneration. The transgene proved to be integrated into maize genome by PCR, PCR-Southern, and Southern blotting analyses. Under the simulated drought condition, one of the transgenic lines showed twice the contents of proline and chlorophyll compared to the wild type. This suggests that drought resistance is improved to some extent in this transgenic line.

摘 要用PCR方法克隆了拟南芥脱水应答转录因子CBF4基因, 以逆境诱导表达基因rd29A的启动子为驱动, 构建了逆境诱导表达载体pBAC146。用基因枪转化法转化玉米优良自交系的幼胚和胚性愈伤组织, 轰击后的愈伤组织经过筛选、分化和植株再生过程, 共获得36棵转基因植株。经PCR、PCR-Southern和Southern检测表明, 外源目的基因已成功整合到部分转基因玉米株系的基因组中。人工干旱处理下, 抗旱生理指标测定显示, 一个转基因株系的脯氨酸含量和叶绿素含量比野生型对照提高一倍, 间接表明转基因株系的抗旱能力在某种程度上有所提高。