Review: The many roles of AVP1, a H+-PPase ($)

avp1The AVP1 gene encodes a proton-pumping pyrophosphatase (H+-PPase) localized to the vacuolar membrane, which means that it pumps H+ into the vacuole using energy stored in pyrophosphatase (PPi). The direct consequences of its action are the acidification of the vacuole and the removal of PPi from the cytosol. Indirect consequences derived from these direct effects include enhanced salinity tolerance, due to sequestration of Na+ in the vacuole via Na+/H+ exchange. However, other effects, such as enhanced plant size in non-stressed conditions, are not so easy to explain. Schilling et al. review the diverse roles of AVP1, including effects on sucrose transport, inferred from knock-out and overexpression studies, and discuss how this gene can be used to increase crop yields. Trends Plant Sci. 10.1016/j.tplants.2016.11.012