Fig. 2

Autophagy is involved in H9N2 influenza virus replication (II). A549 cells were pre-treated with LY294002, control siRNA or Atg5 siRNA, followed by infection with the H9N2 influenza virus. The control siRNA is the scramble siRNA and it has the same nucleotide composition as the target gene sequence. (a) The protein expression levels of Atg5 were detected by western blot analysis. (b, d) Cells were collected and the protein expression levels of Atg5, LC3-II, NP, and M2 were detected by western blot analysis; **P < 0.01 relative to control, ^##P < 0.01 relative to H9N2. (c) Supernatants from A549 cells were collected, and the viral titer was determined by measuring TCID₅₀;**P < 0.01 relative to H9N2. (e, f) NP mRNA was detected by RT-PCR;**P < 0.01 relative to H9N2. The data are presented as the means ± SD (n = 5)