FIG. 7.

Deletion of the mTORC1 target 4EBP1 rescues replication of MCMV in the presence of Torin1. (A) MCMV growth is not inhibited by Torin1 in 4EBP1-null MEFs. Confluent serum-starved cells were infected with MCMV at a multiplicity of 0.05 PFU/cell, and vehicle (black bars) (DMSO), rapamycin (gray bars) (20 nM), or Torin1 (white bars) (250 nM) was added at 1 hpi. At 6 days postinfection the amount of MCMV in cell-free supernatants was determined by the TCID₅₀ method. The error bars represent the standard errors of the means from three independent experiments, each performed in duplicate. (B) Torin1 does not exclude eIF4G or eIF4A from the cap-binding complex in 4EBP1-null MEFs. Cells were infected with MCMV at a multiplicity of 3 PFU/cell and treated with vehicle (N), rapamycin (R), or Torin1 (T) as described above (A). At 48 hpi equal amounts of protein from cell lysates were incubated with m⁷G-Sepharose. The presence of eIF4F complex components bound by the cap analog was determined by Western blotting. The results are representative of two independent experiments.