Functional Analysis of the KUP9 Gene in Response to Drought Stress in Oilseed Rape

Abstract

Potassium transporters are associated with the drought-stress response in oilseed rape, according to this paper. Molecular Features, Transcriptional Regulation and Mechanisms of Change in Potassium Homeostasis for the KUP9 Gene are Studied in this Paper. KUP9 is a protein that has 11 or 12 transmembrane helices and belongs to the KUP/HAK/KT family. The ABRE and DRE elements in the promoter region are associated with the hierarchical regulation of KUP9 by the SnRK2-AREB and DREB2A pathways, and the peak transcript level in root tissue is about 5.6 times that in the control. Overexpression of KUP9 increased the concentration of cytosolic potassium to 82 ± 6 mM, increased the amount of potassium in guard cells, reduced stomatal opening by 28%, and increased the production of proline and trehalose by 2.4-fold and 1.9-fold, respectively. KUP9 can increase the drought tolerance of rapeseed by changing the distribution of potassium in the cell, closing stomata and producing compatible solutes.