Figure 5.

Immunodepletion of CV2 fractions with GAIP antibody reduces its GAP activity. The CV2 fraction was incubated for 1 h at 4°C with 20 μg of affinity-purified anti-GAIP (C) IgG. Immunodepleted fractions were added to [γ-³²P]GTP-loaded Gα_i3 and assayed for GAP activity. Immunodepletion with affinity-purified anti-GAIP(C) IgG (●) decreases by 30% the GAP activity of the CV2 fraction as compared with an irrelevant antibody used as a control (○). The experiment shown is representative of four separate experiments.