关键词: cyFBPase基因, 蔗糖合成, 耐旱性

Abstract: Osmotic adjustment is mainly functioned under drought stress in plant. Sucrose as one kind of important soluble sugar in plant cells, is a primary osmotic regulator in plants, and its synthesis is limited by some key enzymes, such as cyFBPase. In this work, the Brassica napus cyFBPase gene was transformed into tobacco, and the gene expression level and enzyme activity were detected. The cyFBPase gene expression and enzyme activity were increased significantly in transgenic plants, with 1.88 times and 1.55 times of the wild type controls respectively, and at the same time, the sucrose content in transgenic plants leaves was also significantly increased to 1.59 times than that of the wild type. Under the condition of drought, the transgenic tobacco plants showed high drought resistance, and the sucrose content and the distribution of sucrose in root and leaf organs changed significantly. In transgenic plants, the sucrose content in the root and leaves increased by 2.49 times and 9.41 times of the plants which were treated one day, and increased by 1.78 times and 2.71 times of wild type controls under the same drought treatment. In conclusion, overexpression of cyFBPase gene can improve the ability of sucrose biosynthesis of plants, promote the sucrose transportation from leaves to roots under drought stress, and enhance the tolerance of transgenic plants to drought.

Key words: cyFBPase gene, Sucrose synthesis, Drought tolerance