FIGURE 9.

Rac1 is associated with Gβγ and p85α upon thrombin stimulation in A549 cells. A, cells were stimulated with 10 units/ml thrombin for 0–20 min and were then lysed. Cell extracts were immunoprecipitated with an anti-Rac1 antibody, and then immunoblotted with an anti-p85α or anti-Rac1 antibody. IP, immunoprecipitation; IB, immunoblotting. B, A549 cells were stimulated with 10 units/ml thrombin for 0–5 min and then lysed. Cells extracts were immunoprecipitated with anti-Gβ and anti-Gγ antibodies and then immunoblotted with an anti-p85α or anti-Gβ antibody. C, cells were treated with thrombin for the indicated time intervals and then immunoprecipitated with the anti-Rac1 antibody and immunoblotted with the anti-Gβ or anti-Rac1 antibody. α-Tubulin protein in total cell lysates served as the loading control. Typical traces are representative of three experiments with similar results.