Fig. 2. Analysis of Rac1 activation in ETC12 cells adhered to fibronectin. (A) ETC12 cells were incubated in suspension and then aliquots of these cells were adhered to fibronectin (10 µg/ml) for 1 or 2 hours as indicated and the amount of Rac1 GTP-loading was compared in cell lysates. The levels of Rac1 detected by western blot in the GST-PAK pull-down assay (top panel) and the lysate (bottom panel) are shown. (B) The average fold change in Rac1 GTP-loading±s.e.m. from three trials is shown in the bar graph. The level of Rac1-GTP in the suspended cells was normalized to 1. Significant differences are indicated (*).