Requirement for PKCα activity in matrix-dependent fascin localization in C2C12 cells. (A) Western blot of C2C12 whole cell extracts probed with antiserum to PKCα or FAS-C to fascin. (UT) Untreated cells; (T100) cells treated with 100 nM TPA for 24 h; (T500) cells treated with 500 nM TPA for 24 h; (PH500) cells treated with 500 nM 4-α-phorbol for 24 h. (B) Comparison of the localizations of fascin, F-actin, and vinculin in cells treated with 500 nM 4-α-phorbol, 500 nM TPA, or 5 μg/ml 5H10 antibody to integrin α5 subunit after 1 h of adhesion to fibronectin under serum-free conditions. Bar, 5 μm.