Figure 7.

Inhibition of Rho GTPases resulted in cell dissociation and loss of desmosomes in keratinocyte monolayers. HaCaT cells were stained for Dsg 3 (a, c, e, and g) to label desmosomes and for F-actin using ALEXA-phalloidin (b, d, f, and h) to detect sensitively cell dissociation and to visualize effects on the actin cytoskeleton. Compared with untreated cells (a and b), inhibition of all three GTPases Rho A, Rac 1, and Cdc42 by toxin B caused cell dissociation (arrows in c and d), loss of Dsg 3 at cell membranes (c), and complete disruption of actin organization (d). Specific inhibition of Rho A by C3FT and Rac 1 inhibition by LT caused similar effects like PF-IgG (compare with Figure 4, g and i) but less pronounced than toxin B (e–h). Bar = 20 μm.