FIGURE 9.

Effects of ADP on cofilin-mediated depolymerization of actin filaments. WT or D11Q actin filaments in F-buffer containing 0.1 mm ATP were diluted to 5 μm in F-buffer that contained 2 mm Hepes, pH 7.4, and various concentrations of nucleotides. After 30 min of incubation, concentrated Hepes buffer, pH 8.35, and cofilin were added to a final concentration of 10 mm and 10 μm, respectively. After incubation for 15 min, the mixtures were subjected to ultracentrifugation, and supernatant (sup) and pellet fractions were analyzed by SDS-PAGE. A is representative of three independent sets experiments. B shows the average and standard deviation of the three sets of data. The difference between cofilin-induced depolymerization of WT actin and D11Q actin in the presence of 1 mm ATP, as well as that of D11Q actin between 1 mm ATP and 1 mm ADP, were statistically significant by Student's t test (p < 0.001).