A. Rapamycin or wortmannin inhibit the shift in polysomal redistribution of TLK1B mRNA. The cells were irradiated and then incubated for 1 h (as in Fig. 1B) in the presence (or not) of rapamycin or wortmannin. B. IR induces an increase in the amount of eIF4G associated with eIF4E and conversely a decrease in the amount of bound 4E-BP1, both of which are inhibited with rapamycin or wortmannin. 0.1 mg of cell extract from the cells treated as indicated in the figure was adsorbed onto m7GTP-Sepharose for 1 h on ice, after which, the bound protein was resolved on a 10% SDS/PAGE. The gel was blotted onto nitrocellulose and sequentially probed for eIF4G, eIF4E, and 4E-BP1. The total immunoreactive signal from eIF4G was used for the quantitations. The lane labeled 4G is recombinant full-length eIF4G isolated from Sf9 cells.