Improving freezing tolerance of transgenic tobacco expressing-sucrose: sucrose 1-fructosyltransferase gene from Lactuca sativa

作者：Li Hui Juan; Yang Ai Fang; Zhang Xue Cheng; Gao Feng; Zhang Ju Ren^*

来源：Plant Cell, Tissue and Organ Culture, 2007, 89(1): 37-48.

DOI：10.1007/s11240-007-9213-8

• freezing tolerance
• Lactuca sativa
• Ls1-SST
• RACE
• transgenic tobacco

Sucrose: sucrose 1-fructosyltransferase (I-SST) cDNA from Lactuca sativa, coding the enzyme responsible for lower degree polymers fructan biosynthesis, was cloned by RT-PCR and RACE methods. The 1-SST cDNA under the control of CaMV 35S promoter was introduced into tobacco by Agrobacterium-mediated leaf disc transformation protocol. Fructan synthesis in vitro and carbohydrate analysis showed that sense transgenic tobacco plant displayed sucrose: sucrose 1-fructosyltransferse activity. After freezing stress, significant increases in electrolyte leakage and malondialdehyde were found in the wild type and anti-sense transgenic plants, while no apparent differences were observed in sense transgenic plants. Meanwhile, water soluble carbohydrate, fructan and fructose of sense transgenic plants remarkably increased, compared with those of wild type and anti-sense plants. No significant difference was detected in superoxide dismutase activity between transgenic and wild type plants. The above results demonstrated that the expression of 1-SST gene improved the freezing resistance of transgenic tobacco plants.

• 出版日期2007-4
• 单位山东大学; 中国海洋大学