Dual Control of Host Actin Polymerization by a Legionella Effector Pair

Figure 1

LegK2/VipA effector pair controls actin polymerization at the surface of the LCV. (a) Actin polymerization on LCVs during Legionella infection. D. discoideum was infected for 15 min at an MOI of 100 with mCherry-labelled WT, ΔdotA-, ΔlegK2-, ΔvipA-, and ΔlegK2/ΔvipA- mutant L. pneumophila strains. Polymerized actin on LCVs was detected by labelling with phalloidin-FITC. White arrows show examples of actin-positive LCVs. Scale bar, 10 μm. (b) Detection of polymerized actin in ΔdotA, ΔlegK2, ΔvipA, and ΔlegK2/ΔvipA mutant-containing vacuoles. Actin-positive vacuoles () were counted for amoeba infected with L. pneumophila WT, the derivative ΔdotA, ΔlegK2, ΔvipA, and ΔlegK2/ΔvipA mutants. Quantification data are representative of three independent experiments, and the error bars represent the standard deviations from triplicates. Statistical analyses were performed using one-way ANOVA test. ns: no significant difference; ; ; ; .

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