Rac1 restores lamellipodia’s motion after transient retraction when Arp2/3 is inhibited.

(a) Kymograph (upper panel) and fractional height reached by lamellipodia (lower panel) in control conditions (before the black vertical line) and in the presence of 100 μM CK (after the vertical black line). (b) As in (a) but in the presence of 50 μM CK (green line) and of 20 μM EH (blue line). (c) As in (a) but in the presence of 50 μM CK and of 20 μM EH together (yellow vertical line). (d) As in (a) but in the presence of 50 μM ZCL (purple vertical line) and of 50 μM CK (green vertical line). (e) As in (a) but in the presence of 1μg/ml CT04 (brown vertical line) and 50 μM CK (green vertical line). Vertical lines show time at which the inhibitors were added. We observed the same behavior in each case for n ≥ 8 experiments. (f) Period of protrusion/Retraction cycles of lamellipodia in control conditions, with 50 μM ZCL (13 min), with 1μg/ml CT (13 min) and 500nm GSK (13 min). (g) Persistence length of lamellipodia in control conditions, with 50 μM ZCL (13 min), with 1μg/ml CT (13 min) and 500nm GSK (13 min). (h) Retrograde flow rate of lamellipodia in control conditions, with 50 μM ZCL (13 min), with 1μg/ml CT (13 min) and 500nm GSK (13 min). Student t-test showed that the data significantly differ from the control conditions, *P<0.05. Data represent mean ± SEM. (i) Quantification of Rac1-GTP level in DRG neurons in control, 25 μM CK (after 2 min), 50 μM CK (after 2 min) and 50 μM CK (after 8 min) conditions. Student t-test showed that the data significantly differ from the control conditions, n = 8,**P<0.005. Data represent mean ± SEM.