The H⁺ efflux in <i>OsVHA</i><i>-</i><i>A</i>-RNAi lines.

<p>(A) Plasma membrane H⁺-ATPase activity was determined in wild type (WT) and three <i>OsVHA-A</i> RNA interference lines (<i>OsV-5</i>, <i>OsV-11</i>, and <i>OsV-18</i>). (B) Plasma membrane H⁺-ATPase proton-pumping measured by the quenching of ACMA fluorescence. Ten micrograms of tonoplast vesicles were applied to detect fluorescence density. (C) The H⁺ fluxes determined by micro-test system in wild type and transgenic line (<i>OsV-5</i>) under normal (CK) and 20% PEG6000 treatment (PEG). The positive values mean ion effluxes, whereas negative values show ion influx. Values are means ± SE (n = 6). Asterisks (*) indicate significant differences from WT at <i>P</i><0.05.