A Heat Shock-Switchable Gene Expression System

<正> The expression of β-D-glucuronidase(Gus)gene under the control of soybean heat shock protein(HSP)promoter Gmhsp17. 5-C was investigated in transgenic Nicotiana plumbaginifolia plants after heat shock treatment. Results of histochemical stain assay showed that the Gus activity increased markedly during the recovery phase(21℃)after heat shock treatment at 42℃ for 2 h. Results of quantitative fluorometric assays indicated that maximal Gus activity after heat shock treatment could reach 5-6 times higher than that before heat shock treatment in transgenic lines HG6 and HG9. Based on several advantages of the heat shock promoter such as easy to induce, sensitivity to heat shock and high inductive activity, it can be potentially used to control expression of gene of interest in transgenic plants.