FIGURE 2.

YopO does not affect Rac recruitment to FcγR-phagocytic cups. A, COS-7 cells were transiently transfected with FcγRIIA wild-type (wt) or mutant FcγRIIA (Y2F) and either GFP or GFP-YopOwt and then challenged with IgG-opsonized sRBC for 10 min after synchronization at 4 °C. sRBC and endogenous Rac were labeled and observed by confocal microscopy. Rac enrichment at site of sRBC binding was examined. Scale bars, 10 μm. B, quantification of Rac localization to phagocytic cups in cells co-expressing FcγRIIA or FcγRIIA2YF and GFP or YopO-GFP. At least 100 sRBC were scored for the presence of Rac at sRBC cups per experiment. Data are mean ± S.E. of three independent experiments.