FIG 4.

Infection with influenza virus has no significant effect on the protein expression and cellular sublocalization of DDX5. (A, B, and C) A549 cells were infected with influenza virus WSN-H7 (A), WSN/1933 (B), or H9N2 (C) at an MOI of 0.5. At 0 h, 6 h, 12 h, 18 h, and 24 h after infection, cells were lysed to harvest the protein lysate, and protein expression levels were detected by Western blotting. (D) A549 cells were infected with influenza virus WSN/1933 at an MOI of 1. At 0 h, 6 h, and 12 h after infection, nuclear and cytoplasmic proteins were isolated separately. Protein expression levels were detected by Western blotting. The expression levels of viral NP protein and DDX5 were normalized to GAPDH expression using ImageJ. ns, no significance. (E and F) A549 cells were infected with influenza virus WSN/1933 (E) or recombinant influenza virus WSN-H7 (F) at an MOI of 0.5. At 0 h, 4 h, 8 h, and 12 h after infection, cells were fixed, permeabilized, and stained with anti-DDX5 antibody and anti-NP antibody, followed by immunostaining with A546-labeled goat anti-mouse secondary antibody or FITC-labeled goat anti-rabbit secondary antibody. Then, cells were stained with DAPI and examined via fluorescence microscopy.