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

The 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 (PP_i). The direct consequences of its action are the acidification of the vacuole and the removal of PP_i 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