Figure 1

BEFV induces autophagy benefiting virus replication. A MDBK and BHK-21 cells were infected with BEFV at different MOIs for 18 h and the levels of LC3-II were determined. B MDBK cells were seeded in 6-well cell culture dishes with 2 × 10⁵ cells. BEFV-infected MDBK cells at a MOI of 1 for 18 h were then treated with NH₄Cl (20 mM) alone or NH₄Cl (20 mM) combined with rapamycin (5 µM) or starvation (cells supplemented with no FBS), and the cell lysates were collected individually at 18 h post-infection (hpi) for immunoblotting with the respective antibodies. C Cells were pretreated with rapamycin (5 µM) and 3-MA (1.25, 2.5, 5, and 10 mM), respectively, for 30 min and then infected with BEFV at an MOI of 1 for 18 h. The effects of rapamycin and 3-MA on BEFV production were determined by analyzing the expression level of the BEFV M protein (upper panel) and virus titer (lower panel). All data shown represent the mean ± SD calculated from three independent experiments. Signals in all Western blots were quantified with Image J software. The levels of indicated proteins in the mock control (mock, DMSO or un-treatment) were considered onefold. The protein levels were normalised to those for β-actin. The activation and inactivation folds indicated below each lane were normalized against values for the mock control. The predicated size of each protein was labeled at the right-hand side in kDa.