Figure 4.

Mutations of NM23 impair its GAP activity. (A) Wild-type and nm23(Pro96) (50 ng) were incubated with 3 μCi of [α-³²P]GTP in the absence or presence of 1 μg of GST-Rad at 25°C for 5 min. The reaction was stopped by the addition of cold buffer, and the nucleotides were resolved as above. (B) [α-³²P]GTP-loaded Rad was incubated in the absence or presence of one of the following: 60 ng/1 μl of Mono S fraction 20, 0.1 μg each of wild-type nm23, H118F-nm23, and P96S-nm23. The Rad-bound nucleotides were eluted and resolved by TLC.