FIG. 6.

The FAK C-terminal domain can cause FC disassembly. (Top) FAK^916-1053 and FRNK result in marked loss of FCs from HeLa cells as visualized by vinculin staining, but the mutant FRNK(L343S) is ineffective. Expression of each construct was by anti-Flag (middle). Typical cells are shown 2 h after injection with expression plasmid (100 μg/ml). FAK^916-1053-expressing cells begin to narrow and undergo cell body retraction. Similar effects were noted with full-length FAK. (Bottom) Distribution of polymerized actin as visualized by phalloidin-fluorescein isothiocyanate in typical cells expressing ^myrαPAK, ^myrGIT1, or FRNK. Only in the first case is there loss of actin stress fibers. Arrowheads indicate injected cells. Bar, 10 μm.