Figure 2.

cAMP reorganizes the actin cytoskeleton in B16 melanoma cells. B16 melanoma cells growing in serum-containing medium (A and a) were stimulated with forskolin (20 μM) for 5 min (B and b), 1 h (C and c) or 24 h (D and d). F-actin was detected by using phalloidin-rhodamine (A, B, C, and D), and the microtubular network was visualized by an anti-α-tubulin antibody (a, b, c, and d). Arrow in A indicates stress fiber; arrow in B indicates early actin disorganization (punctate actin); arrows in C and c indicate growing dendrites with disorganized actin and positive tubulin labeling. Bar, 40 μm.