FIG 4.

Knockdown of TRIM41 increases IAV infection in A549 cells. (A) A549 cells were transfected with 5 pmol of a scrambled control siRNA or three different siRNA duplexes against TRIM41. After 48 h, cell lysates were blotted with anti-TRIM41 or anti-β-actin antibody. (B) A549 cells were transfected with 5 pmol of the control siRNA or the indicated siRNA duplex against TRIM41. After 48 h, the cells were infected at an MOI of 0.1 with IAV PR8-Gluc for 12 h. Relative luciferase activities were examined. All experiments were biologically repeated three times. Data represent means ± standard deviations of three independent experiments. The P value was calculated (two-tailed Student's t test) by comparison of results with those of the siRNA control in each cell group (*, P < 0.05). (C) A549 cells were transfected with 5 pmol of the control siRNA or the TRIM41 siRNA 2 or 3 duplex for 48 h and then infected at an MOI of 1 with WSN IAV for 12 h. Cell lysates were blotted using the indicated antibodies. (D) A549 cells were transfected with 5 pmol of the control siRNA or the TRIM41 siRNA 3 duplex for 48 h and then infected at an MOI of 0.1 with NY IAV for 12 h. Fixed cells were stained with anti-NP antibody. The percentage of stained cells is summarized in the graph. *, P < 0.05. DAPI, 4′,6′-diamidino-2-phenylindole. (E) Primary human tracheal epithelial cells were transfected with 5 pmol of the control siRNA or the TRIM41 siRNA 3 duplex. After 48 h, the cells were infected at an MOI of 0.1 with PR8-Gluc for 16 h. The relative luciferase activity was examined. Data represent means ± standard deviations of three independent experiments. *, P < 0.05.