Fig. 1. Actin asters are induced by treatment of fibroblasts with cytochalasin. Spreading REF-52 cells (6 hours after plating) were double-stained for actin and myosin II after treatment with 2 µM cytochalasin D for 15 min. Actin is shown in cyan and myosin in red. Areas of superimposition of high intensities of staining for both actin and myosin are represented in white. Inset in (b) shows gallery of actin asters with myosin II spot in the center and tapered actin bundles with myosin II spot at the base. Gallery images were cut out from different regions of the cell. Bar, 2 µm.