FIG. 9.

Downregulation of NF45 expression increases viral IBDV titers. NF45 expression and virus titers in the supernatants of IBDV-infected DF-1 cells were investigated after transfection with the NF45-specific siRNAs 185 (si185) and 551 (si551), either alone or in combination (si185 si551). Three controls were applied in these experiments: a nonspecific siRNA (Con-siRNA), mock-transfected cells (Mock) and untransfected cells (Con). Protein expression of NF45 was analyzed by Western blotting with protein samples taken from parallel transfected cells before infection and at the time of harvest of the cell culture supernatant (after infection). The analyzed protein amount was normalized for chicken β-actin by using an HRP-conjugated mouse β-actin MAb. The presence of cellular NF45 was analyzed using the rabbit anti-ckNF45-His serum. The graphs show the average measured virus titers (in TCID₅₀/ml) analyzed in DF-1 cells from three individual experiments. Error bars show the standard deviations. The average titer value is shown within the corresponding column.