Figure 1

Progestins induce a rapid rearrangement of the actin cytoskeleton in T47-D cells. T47-D cells were treated with P, MPA, DRSP (all 100 nM) or NES (1 nM) for 10, 15 or 30 minutes, in the presence or absence of the pure PR antagonist ORG 31710 (1 μM). Immunofluorescent staining of actin (in red) reveals the spatial modifications of actin fibers through the time-course and the formation of specialized cell membrane structures (yellow arrows indicate longitudinal actin fibers, green arrows show pseudopodia, light blue arrows indicate ruffles). Nuclei are counterstained in blue.