A CkDREB1 gene isolated from Caragana korshinskii Kom. enhances Arabidopsis drought and cold tolerance

Caragana korshinskii Kom., an arbuscular legume with important economic and ecological value in feed, processing industry, and environmental protection, also has great tolerance potential to abiotic stress conditions. An AP2 domain-containing gene was isolated from the suppression subtractive hybridization library of C. korshinskii under drought stress. In addition, the isolated gene was also found to be responsive to cold and ABA treatment. Phylogenetic analysis indicates that the deduced protein belongs to the DREB A-1subfamily and is designated as CkDREB1. Overexpression of CkDREB1 in Arabidopsis thaliana (L.) Heynh increased drought and cold tolerance compared with the wild type. The drought responsive genes RD29A, RD29B, KIN1, and KIN2, as well as cold-responsive marker genes COR15A and COR47, were also highly induced in the overexpression lines under drought and cold conditions. These results should shed light on our understanding on the mechanisms of abiotic resistance of C. korshinskii.