Figure 4.

Legionella RavZ appears to remove ubiquitin from SCVs in a manner dependent on the catalytic residue responsible for autophagy inhibition. (A,D) 3xFLAG-RavZ or its catalytic mutant was expressed in HeLa cells by transfection. The cells were infected with Salmonella expressing mCherry (A) or Legionella (D) for 1 h. (B,C) The purified His-tagged RavZ or its catalytic mutant protein was supplied into HeLa cells expressing GFP-LC3 (B) or HeLa cells (C) semi-permeabilized with Digitonin-containing buffer after 1 h of infection with Salmonella expressing mCherry. Conjugated ubiquitin was stained with the FK2 antibody. Average percentage of LC3 (B) or ubiquitin (A,C,D)-positive SCVs or LCVs calculated from three independent examinations. Data present the average ± SD; ^*P < 0.02, ^**P < 0.01.