HeLa cells were infected with C. burnetii for different lengths of time, lysed and centrifuged to obtain postnuclear supernatant, membrane and cytosolic fractions as described in Materials and Methods. (A) Postnuclear supernatant (T: total), cytosol (C) and membrane (M) fractions were analyzed by SDS-PAGE and Western blot using antibodies against RhoA and Rac1. Anti-actin and anti-E cadherin antibodies were used as loading controls. (B) Quantification of RhoA or Rac1 recruitment to the membrane fraction. The band intensities corresponding to RhoA, Rac1, E cadherin and actin were measured by the ImageJ software, and the band intensity ratio between RhoA and E cadherin, and Rac1 and E cadherin in the membrane fractions was calculated. Results are expressed as means ± SE from at least three independent experiments. Mean values were compared with the 0 min infection condition by Student’s t test for single group mean (*p < 0.05, ***p < 0.001). ns: non-significant differences between groups (p > 0.05). RU: Relative Units.