热激诱导表达Hd3a的水稻转基因研究

Studies on Transgenic Rice with Heat-shock Inducible Expression of Hd3a Gene

Hd3a(Heading date 3a)基因是光周期诱导水稻开花过程中的一个关键调控基因,它在短日条件下表达并促进水稻开花.通过根癌农杆菌介导的方法将热激诱导表达的Hd3a基因转化到水稻品种日本晴中.热激处理转基因植株后,检测结果表明,叶片中转基因Hd3a的表达水平比热激前显著提高,随后又下降到热激前的水平,说明转基因Hd3a在水稻中可以被热激诱导瞬间的表达.长日条件下热激转基因水稻可成功诱导其抽穗,而同样处理的野生型植株不能抽穗,表明Hd3a的瞬间表达可诱导水稻开花,且其开花的早晚与热激处理的强度有关.

Hd3a（Heading date 3a） plays a key regulatory role in the photoperiod flowering pathway of rice （Oryza sativa）. In this study,a heat-shock inducible Hd3a gene was transformed into wild-type rice mediated by Agrobacteriurn tumifaciens. The result of real-time PCR analysis showed that the expression level of transgene Hd3a increased significantly after heating treatment, and soon decreased to the background level, which suggested that Hd3a expression can be induced transiently to a very high level. In the longday condition,the flowering of transgenic rice can be induced by heating treatment, while wild type plants can not flower with the same treatment. It proved that a transient expression of Hd3a could induce transgenic rice to flower. There was a positive correlation between flowering time and heating treatment times.