The Maize Root Plasma Membrane H+-ATPase is Regulated by a Sugar-induced Transduction Pathway

H+-ATPase, the key enzyme for the energization of ion and nutrient transport across the plasma membrane, is activated by phosphorylation-dependent 14-3-3 binding. Since the involvement of 14-3-3 proteins in sugar sensing-regulated processes has recently emerged, here we address the question as to whether sugar sensing plays a role in the regulation of H+-ATPase. The data reported here show that sugar depletion inhibits the association of 14-3-3 proteins with H+-ATPase by hampering phosphorylation of the 14-3-3 binding site of the enzyme. By using non-metabolizable disaccharides, we show that H+-ATPase regulation by 14-3-3 proteins can involve a specific sugar perception and transduction mechanism.