Figure 3.

Rac1 Coordinately Promotes Cell Cycle Progression and Cell Motility in Keratinocyte Sheets

(A) Lysates of keratinocyte sheets grown for 30 h after seeding cells in the presence of DMSO (control) or the Rac1 inhibitor (20 μM NSC23766) were subjected to the PAK1-PBD-based pull-down assay for active Rac1.

(B) Immunofluorescence images of cortactin and F-actin in keratinocyte sheets at 30 h after seeding cells in the presence of DMSO (control) or the Rac1 inhibitor (20 μM NSC23766). Merged images are also shown. Scale bar, 30 μm.

(C and D) Time-dependent changes in the average speed (B) and the ratio of Geminin-positive cells against total cells (C) in keratinocyte sheets after seeding cells in the presence of DMSO (control) or the Rac1 inhibitor (20 μM NSC23766). Each data point represents mean ± SD. n = 3 (>100 cells at each time point in each experiment in (D)).

(E) The ratio of Geminin-positive cells was plotted against the average speed at each time point throughout observation under control (DMSO) and Rac1-inhibited (20 μM NSC23766) conditions. Data from three independent experiments were combined for each condition. The regression line of linear fitting is shown.

(F) Duration of S to M phases (i.e., from appearance of the Geminin signal to cell division) in individual cells within keratinocyte sheets under control (DMSO) and Rac1-inhibited (20 μM NSC23766) conditions. n = 36. n.s., no significant difference (Student's two-tailed, unpaired t test).

See also Figures S11 and S12, and Videos S7 and S8.