Fig. 6. Inactivation of WAVE1 or co-inactivation of WAVE1 together with N-WASP in WAVE2-knockdown cells profoundly affects HGF-induced actin cytoskeleton rearrangements. (A) HGF (0.6 nM) stimulation induces formation of peripheral (P) and dorsal (D) ruffles in HeLa cells. (B) WAVE2 knockdown (K.D.) HeLa cells were non-transfected (NT) or transfected with WAVE1 siRNA (W1) or co-transfected with WAVE1 and N-WASP siRNA (W1+NW), and stimulated or not with HGF, fixed and stained with phalloidin-488 to detect F-actin. Resting cells display no apparent morphological alterations. Ruffles are mainly formed in WAVE2-knockdown cells. Filopodia are mainly formed in WAVE2-knockdown cells treated with WAVE1 siRNA. Cells detach from each other in WAVE2-knockdown cells treated with WASP1 + NWASP siRNA. Squared regions indicate the position of the fields magnified below. D, dorsal; J, cell junctions; P, peripheral. Bar, 10 µm.