RhoG mediates EGF-induced Rac1 activation. A) RhoG is activated by EGF (50 ng/ml) in SNB19 cells. Western blot shows activated RhoG and total RhoG for HGF-stimulated and controls cells. Histogram shows quantification (+/− SEM) of 5 independent experiments (p < 0.05, two-tailed t test). B) RhoG mediates EGF-induced Rac activation. Cells were transfected with siRNAs (10 nM) directed against luciferase (control) or RhoG-2. Forty eight hours after transfection, cells were serum starved for 24 hours, and incubated further with or without EGF for the indicated time periods. Rac activity was determined as in Figure 2B. The results shown represent the means +/− SEM of 3 independent experiments (* = p < 0.05, two-tailed t test).