Figure 7.

Activation of Rho or Rac is not sufficient to redistribute cadherin receptors and Cy3-labeled actin to the periphery of keratinocyte cells. Starved Swiss 3T3 fibroblasts were microinjected with L61Rac and Cy3-labeled actin (A) and after 20 min incubation, cells were fixed and stained with FITC-phalloidin (B). Keratinocytes grown in the absence of cell–cell contacts were injected with Cy3-actin and activated Rac (L61Rac, panels C–F) or activated Rho (L63Rho, panels G and H). Cells were incubated for 20 min in the same medium (low calcium, panels E–H) or immediately transferred to standard calcium medium to induce intercellular contacts (std calcium, panels C and D). Staining for E-cadherin receptors was performed (D, F, and H) and Cy3-actin pattern in injected cells was shown (A, C, E, and G). Arrows in panels A and C indicate accumulation of Cy3-actin at the cell periphery; arrows in E and G show diffuse localization of labeled actin. Bar, 50 μm.