The Study On MfDREB1 Transcription Factor Which Improved The Stress Resistance Of Transgenic Tabacco

The transgenic tobacco of T1 generation, which overexpressed sickle alfalfa stress-related transcription factor MfDREB1 and transformed empty vector without purpose gene, was used as the research material in this study. And 72 transgenic homozygous lines of T3 generation were obtained through selling screened in the tobacco. The wild-type and homozygous transgenic tobacco lines A3-6 and B3-8 were treated with 0℃,300 mM NaCl and 20% PEG6000 to simulate abiotic environments under laboratory conditions. The phenotype of tobacco showed that MfDREBl significantly improved its stress resistance.The real-time quantitative PCR technique was used to analyse the expression characteristic of MfDREB1 gene. The results showed that relative gene expression levels of MfDREBl, NtERD10A and NtP5CS were all increased at first, after decreased and then increased in the transgenic tobacco line A3-6 which overexpressed MfDREB1 gene after abiotic stress treatment, and the relative gene expression levels of MfDREB1, NtERD10A and NtP5CS did not change obviously in the wild-type tobacco and transgenic tobacco line B3-8 which transformed empty vector.The recombinant fragment was used as the hybridization probe, which belong to overexpression vector pPZP221 (35S-MfDREB1-NOS), and the digoxin was labeled to detect the homozygous transgenic tobacco lines. The Southern Blot showed that the genome of transgenic tobacco line A3-6 which overexpressed MfDREBl gene was inserted 3 copies of exogenous recombinant fragment, the genomes of wild-type tobacco and transgenic tobacco line B3-8 which transformed empty vector were not detected exogenous recombinant fragment.