Sucrose Transporter Gene AtSUC4 Responds to Drought Stress by Regulating the Sucrose Distribution and Metabolism in Arabidopsis Thaliana

摘要

Sucrose transporters (SUCs or SUTs) are considered as the important carriers and responsible for the loading, unloading and distribution of sucrose, but at present there is no report that SUCs are involved in sucrose distribution and metabolism under drought stress at the whole-plant level. AtSUC4, as the unique member of SUT4-clade in Arabidopsis thaliana, may be important for plant stress tolerance. Here, by analyzing two homozygous mutation lines of AtSUC4 (Atsuc4-1 and Atsuc4-2), we found drought stress induced higher sucrose, lower fructose and glucose contents in shoots, and lower sucrose, higher fructose and glucose contents in roots of these mutants compared with the wild-type (WT), leading to an imbalance of sucrose distribution, fructose and glucose (sucrose metabolites) accumulation changes at the whole-plant level. Thus we believe that AtSUC4 regulates sucrose distribution and metabolism in response to drought stress.