The aluminum (Al)-induced secretion of citrate has been regarded as an important mechanism for Al resistance in soybean (Glycine max). However, the mechanism of how Al induces citrate secretion remains unclear. In this study, we investigated the regulatory role of plasma membrane H 1 -ATPase activity and expression were higher in an Al-resistant cultivar than in an Al-sensitive cultivar. Al activated the threonine-oriented phosphorylation of plasma membrane H 1 -ATPase in a dose-and time-dependent manner. Taken together, our results demonstrated that up-regulation of plasma membrane H 1 -ATPase activity was associated with the secretion of citrate from soybean roots.

In the original publication, contributing author Hideo Sasakawa was incorrectly listed as Sasakawa Hideo. The online version has been replaced to reflect the correct author list.