FIGURE 5.

RSK2 activity is required for actin and talin rearrangements that promote migration. HeLa cells were seeded on fibronectin-coated glass coverslips and allowed to grow to confluence. Growth medium was then replaced with medium containing 0.5% serum and incubated overnight. The coverslips were scratched with a micropipette tip and then treated with vehicle (A), SL0101-1 (100 μm) (B and D), or EGF (100 ng/ml) (C and D) and allowed to incubate an additional 2 h followed by fixation. The coverslips were then stained with phalloidin and antibody against talin to visualize actin and focal adhesions by confocal microscopy. Treatment with EGF leads to peripheral ruffle formation and redistribution of talin. However, when the cells are treated with SL0101-1 in addition to EGF, talin remains predominantly at the focal adhesions, and actin filaments become stabilized at the leading edge. The scale bars shown represent 25 μm.