Plasma membrane H+-ATPases in mineral nutrition and crop improvement.

Plasma membrane H+-ATPases (PMAs) provide an H+ electrochemical gradient to establish a proton motive force and membrane potential for the transport of various nutrients across the plasma membrane. PMAs are regulated at multiple levels, and genetic modulation of PMA expression could enhance nutrient acquisition and use efficiency in plants. PMAs are involved in the coordination of the uptake and assimilation of both nitrate and ammonium. PMAs are involved in nutrient utilization by regulating root growth, facilitating organic anion exudation, and promoting the acquisition of nutrients through H+ extrusion-mediated apoplast and rhizosphere acidification. PMAs play essential roles in mycorrhizal symbioses in plant roots for nutrient acquisition. Plasma membrane H+-ATPases (PMAs) pump H+ out of the cytoplasm by consuming ATP to generate a membrane potential and proton motive force for the transmembrane transport of nutrients into and out of plant cells. PMAs are involved in nutrient acquisition by regulating root growth, nutrient uptake, and translocation, as well as the establishment of symbiosis with arbuscular mycorrhizas. Under nutrient stresses, PMAs are activated to pump more H+ and promote organic anion excretion, thus improving nutrient availability in the rhizosphere. Herein we review recent progress in the physiological functions and the underlying molecular mechanisms of PMAs in the efficient acquisition and utilization of various nutrients in plants. We also discuss perspectives for the application of PMAs in improving crop production and quality. [ABSTRACT FROM AUTHOR]