DsSWEET17, a Tonoplast-Localized Sugar Transporter from Dianthus spiculifolius , Affects Sugar Metabolism and Confers Multiple Stress Tolerance in Arabidopsis

Plant SWEETs (Sugars Will Eventually be Exported Transporters) affect the growth of plants by regulating the transport of sugar from source to sink and its intracellular transport between different organelles. In this study, from was identified and characterized. Real-time quantitative PCR analysis revealed that the expression of was affected by exogenous application of fructose and glucose as well as under salt, osmotic, and oxidation stress. Colocalization experiments showed that the DsSWEET17-GFP (green fluorescent protein) fusion protein was localized to the FM4-64-labeled tonoplasts in . Compared to the wild type, the transgenic seedlings overexpressing had longer roots, greater fresh weight, and a faster root growth upon exogenous application of fructose. Furthermore, transgenic seedlings had significantly higher fructose accumulation than was observed for the wild-type seedlings. The analysis of root length revealed that transgenic had higher tolerance to salt, osmotic, and oxidative stresses. Taken together, our results suggest that DsSWEET17 may be a tonoplast sugar transporter, and its overexpression affects sugar metabolism and confers multiple stress tolerance in .