Figure 6.

Actin dynamics of villin-expressing cells relies on a higher available pool of actin monomers than in repressed cells. The G-actin pool was visualized using fluorescent DNase I, which binds to actin monomers with a high affinity. Cells were either unstimulated (a) or stimulated with HGF (10 UI/ml) for 2 h (b) and 6 h (c). Arrows show maintenance of G-actin labeling in the leading edge of induced cells after 6 h of HGF treatment. Fluorescence intensity in the lamellipodia was quantified using MetaMorph software (d). Among the induced cells, 26 nonstimulated cells, 31 cells treated with HGF for 2 h, and 30 cells treated with HGF for 6 h were analyzed. Among the repressed cells, 31 nonstimulated cells, 36 cells treated with HGF for 2 h, and 30 cells treated with HGF for 6 h were analyzed. (p = 0.026 at 2 h; p = 0.001 at 6 h).