FIG. 4.

The constitutively active form of Rab5 (Rab5Q79L) localizes with the C. burnetii-containing vacuole. Coxiella-infected HeLa cells were incubated for 1 h with recombinant Sindbis viruses encoding the GFP-Rab5wt fusion protein, negative mutant GFP-Rab5S34N, or active mutant GFP-Rab5Q79L. After overnight incubations at 37°C in an air atmosphere, cells were analyzed by phase-contrast (PC; left) and fluorescence (right) microscopy. Coxiella-containing vacuoles did not colocalize with GFP-Rab5wt and GFP-Rab5S34N proteins (top and middle, respectively). Interestingly, the Coxiella-containing vacuole membrane was strongly labeled by GFP-Rab5Q79L (bottom).