FIG. 7.
N-WASP recruitment and F-actin comet tail formation by intracellular S. flexneri strains expressing IcsA deletion mutant proteins with either smooth or rough LPS. IF microscopy of F-actin tail formation and N-WASP recruitment by intracellular S. flexneri strains expressing IcsAΔ mutants. HeLa cells were infected with S. flexneri ΔicsA (S-LPS) or S. flexneri ΔicsA ΔrmlD (R-LPS) strains expressing IcsA deletion mutant proteins and formalin fixed. Bacteria were labeled with DAPI (blue), F-actin was labeled with FITC-phalloidin (green), and N-WASP was labeled with anti-N-WASP and Alex 594-conjugated donkey antirabbit antibodies (red) as detailed in Materials and Methods. Arrows indicate F-actin tail formation or N-WASP recruitment. Strains were assessed in two independent experiments. Bar = 10 μm.