OsUgp2和otsAB基因共转化增强水稻抗旱抗寒能力

本研究通过农杆菌介导的转化技术，将水稻尿苷-2磷酸葡萄糖焦磷酸化酶基N（OsUgp2）与大肠杆菌海藻糖-6-磷酸合成酶／海藻糖-6-磷酸合成酶磷脂酶融合基因（otsAB）共表达载体转化水稻愈伤组织，对获得的转基因植株分别进行干旱和寒冷处理，试图明确0sUgp2和otsAB共表达是否可以进一步提高转基因水稻植株的抗胁迫能力。表型观察结果显示0sUgp2和。拈AB共表达植株（ABu）经干旱和寒冷处理后恢复生长的能力，较otsAB和OsUgp2分别过量表达的转化植株（AB和U）均有所提高。定量PCR检测结果显示：经干旱处理后，转化植株ABU中0tsAB和OsUgp2的表达量较未处理植株分别提高1．92倍和1．67倍，与转化植株AB和I中0tsAB和OsUgp2表达的增加量相近；而寒冷处理后，转化植株ABU中otsAB和OsUgp2的表达量分别增加2．68倍和2．04倍，明显高于转化植株AB和u中otsAB和OsUgp2表达的增加量。液相色谱检测结果显示：OsUgp2和otsAB共表达和单表达均可以提高转化植株中海藻糖的生物合成量，且共转化植株ABU中海藻糖的含量在干旱和寒冷处理前后均是最高的。干旱和寒冷处理后，共转化植株ABU中蔗糖含量的增加也较明显。本研究结果表明OsUgp2和otsAB共表达可以增加转基因水稻植株中海藻糖和蔗糖分子的含量，同时转基因水稻植株的抗旱和耐冷胁迫的能力也得到了一定提高。

Co-expression of OsUgp2 and otsAB in Rice Increasing Its Resistance to Drought and Cold Stresses

Rice UDP-glucose pyrophosphorylase gene （Os Ugp2） and a fusion gene oftrehalose-6-phosphate synthase/trehalose-6-phosphate phosphatase （otsA B） in E. coli were co-expressed in rice in order to find out if the ability of drought and cold resistance in transgenic rice will be further improved. The phenotypes of the drought and cold treated rice seedlings showed that the surviving ability of transgenic rice co-expressed OsUgp2 and otsA B （ABU） was better than that of rice over-expressed otsAB （AB） or Os Ugp2 （U） separately. The results of realtime PCR revealed that the expression levels of otsAB and OsUgp2 in ABU were increased 1.92 and 1.67-folds after drought treatment, which was similar with that in AB and U. However, the expression quantities of otsA B and Os- Ugp2 in ABU were increased 2.68 and 2.04-folds after cold treatment, which was much higher than that in AB and U. Furthermore, the detection of liquid chromatography indicated that the contents of trehalose in ABU, AB and U were all increased compared with non-transgenic rice ZH11, and that the content oftrehalose in ABU remained the highest preor after drought and cold treatments among the three. Besides, the content of sucrose in ABU was also found enhanced eminently after drought and cold treatments. It was concluded that co-expression of Os Ugp2 and otsA B led to the increase in the contents oftrehalose and sucrose in transgenic rice, which were considered correlative to its improved resistance to drought and cold stresses.