Figure 4. S79A mutation abolishes the migration activity of PAK1.

The benign prostate RWPE-1 cells infected with lentivirus expressing the vector plasmid, GFP- PAK1^WT (WT), or GFP-PAK1^S79A (S79A) were used for experiments (A) to (E). (A) The invasion rate was determined by counting the cells that migrated through BME-coated inserts in the Transwell Boyden chamber and expressed as the percentage relative to control (vector). Each bar represents the mean ± S.D of five fields counted. ^a) Western blot analysis of PAK1 expression using anti-GFP antibody. Actin was used as an internal control. (B) The S79A mutation impairs the ability of PAK1 to regulate formation of membrane ruffles of cells. RWPE-1 cells infected with lentivirus expressing the vector plasmid (a–c), GFP-PAK1^WT (WT, d–f) or GFP-PAK1^S79A (S79A, g–i) were stained with Phalloidin (red) and DAPI (blue) and visualized by GFP fluorescence (green). (C) Quantification of the cells with membrane ruffles (B). (D) Wound healing migration assays of RWPE-1 cells expressing GFP-PAK1 or GFP-PAK1^S79A. (E) Each bar represents the mean ± S.D of five fields measured in (D).