Cloning of Ammopiptanthus mongolicus C-repeat-binding factor Gene and Its Cold-induced Tolerance in Transgenic Tobacco

C-repeat-binding factors (CBFs) are a type of important regulon in stress-related signal transduction pathways that control plant tolerance of abiotic stress. Ammopiptanthus mongolicus is the only evergreen broadleaf shrub in the northwest desert of China. The species shows strong resistance to environmental stress, especially to cold stress. An A. mongolicus CBF1 gene (AmCBF1) was cloned and transformed into tobacco. Expression of AmCBF1 could be detected in A. mongolicus shortly after exposure to low temperature of 4°C. Analysis on ratio of electrolytic leakage, soluble sugar content, free proline content, malondialdehyde (MDA) content and peroxidase (POD) activity before and after cold treatment (4°C) for 24 h indicated AmCBF1 conferred higher cold tolerance to AmCBF1 transgenic tobacco compared with the wild type and empty vector transformed