FIG 2 .

E4orf6/E1B55K increases the stability of E1A. (A) H1299 cells were transfected with plasmid DNA expressing E4orf6, E1B55K, and various amounts of E1A as indicated for 48 h. Whole-cell extracts were immunoblotted as indicated using the appropriate antibodies. (B) H1299 cells were transfected with plasmid DNAs expressing E4orf6, E1B55K, and 13S E1A for 43 h followed by 0 to 5 h after addition of 25 μg/ml cycloheximide. Whole-cell extracts were immunoblotted using E1A antibodies, and the blots were scanned and quantified with ImageJ. Each condition was normalized to its time zero (average of three experiments). (C) H1299 cells were infected with the indicated viruses at an MOI of 5 and harvested at the indicated times. Whole-cell extracts were immunoblotted as indicated using the appropriate antibodies. WT virus, H5pg4100; E4orf6-deleted, H5pm4154; E1B55K-deleted, H5pm4149. (D) H1299 cells were transfected with plasmid DNAs expressing E4orf6, E1B55K, and E1A as indicated for 48 h. Whole-cell extracts were immunoblotted as indicated using the appropriate antibodies.