PSaV infection depends on Rab5 and Rab7. A–D LLC-PK, Caco-2, and MA104 cells were transfected with scrambled siRNA or siRNAs against Rab5 or Rab7, and then incubated with PSaV Cowden (A), CVB3 Nancy (B), or rotavirus Wa (C) strains, respectively. Infected cells were counted after staining with antibodies specific for each virus, and nuclei were counted after staining with DAPI. For each virus, results are shown as the percentage of infected cells, normalized to the results obtained in the scrambled siRNA-transfected cells. D The virus titer was determined by TCID50 using the cell lysates harvested from the cells in the above experimental conditions. Data for panels A–D are presented as mean ± standard deviation of the mean from three independent experiments. Differences were evaluated using the one-way ANOVA. *P < 0.05; **P < 0.001; ***P < 0.0001. E The level of PSaV VPg protein production in the above conditions was determined by western blotting analysis. GAPDH was used as a loading control. The intensity of PSaV VPg protein relative to GAPDH was determined by densitometric analysis and is indicated above its lane.