Fig. 3.

Nonmuscle myosin II (NMII) plays a role in EHEC-stimulated Stx1 MPC. A: representative immunoblot of Stx1-Alexa 680 and GAPDH from infected and uninfected T84 cells that were treated or not with 50 μM blebbistatin or 5 nM calyculin A for 4 h. B: treatments of T84 cells with either 50 μM blebbistatin or 5 nM calyculin A for 4 h affect EHEC-induced Stx1 MPC; n ≥ 3 per each condition. C: immunoblot of T84 total cell lysates shows increase in RLC phosphorylation upon EHEC infection with corresponding quantification of RLC phosphorylation. *Significant compared with uninfected cells (P < 0.05; n = 5). D: representative immunoblot of MNIIA shows the increase in the NMIIA amount in cells infected for 4 h with EDL933 compared with control uninfected cells. E: representative immunoblot of MNIIB shows no changes in the NMIIB amount in cells infected for 4 h with EDL933 compared with control uninfected cells. F–G: NMIIA is present in F-actin apical blebs induced by EDL933. Representative XY optical section through the apical region with corresponding XZ projection of T84 cells uninfected (F) or infected (G) with EDL933 for 4 h and immunostained against NMIIA with F-actin; green by phalloidin-AlexaFluor488 and to visualize NMIIA. The pattern of NMIIA overlaps with the pattern of F-actin at the perimeter of the bleb.