Figure 2.

F-actin polymerization responses on cAMP stimulation of Dictyostelium mutants. The F-actin content was determined by tetramethylrhodamine B isothiocyanate-phalloidin staining of cells fixed at various times after stimulation with 50 μM cAMP (see Materials and Methods). The amount of F-actin was normalized relative to the F-actin level of unstimulated wild-type cells (t = 0). Each data point represents the average of two or three independent measurements. Error bars are shown only at 0 and 10 s to avoid complexity.