FIG. 6.

ATF4 expression in reovirus-infected cells and its impact on reovirus replication. (A and B) L929 cells were mock infected or infected with the indicated strains of reovirus at an MOI of 80 PFU/cell, and cell extracts were harvested at 19.5 h p.i. Samples were adjusted to contain 20 μg of protein for eIF2α analysis and 25 μg of protein for ATF4 analysis. The levels of phosphorylated eIF2α (A, top), total eIF2α (A, bottom), and ATF4 (B) were examined by immunoblot analysis. The band intensities for phosphorylated and total eIF2α were determined using NIH Image. The ratio of phosphorylated eIF2α to total eIF2α was set at 1 for mock-infected cells, and relative ratios for the infected samples are displayed beneath panel A. (C) Primary wt and ATF4 KO MEFs were infected with the indicated strains of reovirus at an MOI of 2 PFU/cell. The amounts of infectious virus present at 0, 1, 3, and 5 days p.i. were determined as described in the legend to Fig. 4.