Fig. 7. Role of Rho family GTPases in syndecan-4 endocytosis. The effect of pre-treatment with C. difficile toxin B (A) and C3 exotransferase (B) on syndecan-4 endocytosis was examined in antibody-clustered FcR-S4 chimeras. Note that while toxin B treatment completely inhibited FcR-S4 endocytosis, C3 exotransferase had no effect. Scale bars, 10 µm.