The dehydrin gene of the Arctic plant Cerastium arcticum , CaDHN, increases tolerance to multiple stresses in Arabidopsis thaliana

Cerastium arcticum is one of the few flowering plants that thrives in the Arctic, suggesting that it possesses mechanisms for overcoming this extreme environment. To verify the functionality of C. arcticum dehydrin (CaDHN), known to play a protective role during cellular dehydration, the gene was introduced to Arabidopsis and Escherichia coli. Transgenic plants expressing CaDHN had significantly greater fresh weight and relative water content than wild-type plants under 15% PEG treatments, representing enhanced tolerance to drought. Under chilling conditions, transgenic plants remained vivid green, containing about 1.35-fold higher levels of chlorophyll than wild-type plants, and transgenic seeds germinated 2–3 days earlier with approximately threefold higher germination rates than wild-type seeds. Furthermore, oxidative stress under chilling conditions was 30% lower in transgenic plants than in wild-type plants. Transgenic plants also showed improved tolerance to various stresses, such as cold shock and salinity. In addition, transformed E. coli expressing CaDHN also showed enhanced tolerance to stress conditions, which suggests that CaDHN is conserved across taxa to provide tolerance to stress. These results indicate that CaDHN plays an important role in conferring tolerance to oxidative stress.