FIGURE 7.
In vivo acidification rate and immunodetection of ectopic PMA2 in N. tabacum BY2 cells expressing PMA2, PMA2 T889D, or PMA2 T889A. A, acidification of the external medium by N. tabacum BY2 cells was measured (pH unit·min−1·g−1 (UpH.min−1g−1, cell fresh weight)) as indicated under “Experimental Procedures.” The data are the mean and confidence interval (95%) for four independent experiments, with several replicates per experiment. B, immunodetection of His tag PMA2, PMA2, and PMA4. Microsomal membrane fractions (10 μg of protein) were analyzed by SDS-PAGE and Western blotting using antibodies against His-tagged PMA2 (top), PMA2 (middle), and PMA4 (bottom).