Figure 5.
Sucrose-mediated changes in symporter activity were reversible. Four leaves were cut from an individual plant, and two of them were placed in H2O and the other two in 100 mM sucrose. Plasma membranes were purified from one leaf of each treatment after 24-h transpirational feeding. At the same time, petioles of the other two leaves were recut, and those leaves were placed in the opposite treatment solution [i.e., H2O-treated leaves into 100 mM sucrose (H2O/Suc), and sucrose-treated leaves into H2O (Suc/H2O)] for another 24 h before isolating plasma membrane vesicles.