The Poplar () Dehydrin Gene Enhances Tolerance to Salt Stress in Arabidopsis.

Dehydrin (DHN), a member of the late embryogenesis abundant protein (LEA) family, was recently found to play a role in physiological responses to salt and drought stress. In this study, we identified and cloned the gene from . The PtrDHN-3 protein encoded 226 amino acids, having a molecular weight of 25.78 KDa and an isoelectric point of 5.18. It was identified as a SKn-type DHN and was clustered with other resistance-related DHN proteins. Real-time fluorescent quantitative PCR showed that transcription levels of were induced by mannitol stress, and more significantly by salt stress. Meanwhile, in a yeast transgenic assay, salt tolerance increased in the transgenic yeast, while the germination rate, fresh weight and chlorophyll content increased in -overexpressing transgenic plants (OE) under salt stress. Significant increases in expression levels of six antioxidant enzymes genes, and SOD and POD enzyme activity was also observed in the OE lines, resulting in a decrease in O and HO accumulation. The proline content also increased significantly compared with the wild-type, along with expression of proline synthesis-related genes and . These findings suggest that plays an important role in salt resistance in plants.