FIGURE 7:

Roy1 inhibits the formation of active, GTP-bound Ypt52. GST-Ypt52 or GST was incubated with BSA or Roy1–Skp1 complex at 30°C for 30 min and then mixed with [γ-³²P]GTP at 30°C for 5 min. The amount of protein-bound GTP was analyzed as described in Materials and Methods. Data are expressed as a percentage of the [³²P]GTP binding of GST-Ypt52 + BSA and are the means ± SD from three independent experiments.