FIGURE 6.

Effect of the tandem PH domains PH1 and PH2 on the enzymatic power of ARAP1. PH1-Ank, mutants of PH1-Ank, and ArfGAP-Ank were titrated into reactions containing myrArf5·GTP as a substrate and LUVs containing 2.5 μm PtdIns(3,4,5)P₃. Reactions were terminated after 3 min. Averages ± S.E. from at least three experiments are presented. A, PH1-Ank, [K347N]PH1-Ank, [R351Q]PH1-Ank, and [K455N]PH1-Ank. B, [K336N]PH1-Ank, [R348Q]PH1-Ank, [R450Q]PH1-Ank, and [K453N]PH1-Ank. C, ArfGAP-Ank. The C₅₀ values ± S.E. derived from these results are presented in Table 3.