Figure 4.

Effect of inhibition of PP2A (A and C-E) or Mnk (B and D) on the assembly of eIF4E with eIF4G (A and B), 4EBP-1 and eIF4E interaction (C and D), and 4EBP-1 phosphorylation (E). (A, C, and D) The indicated cell lines were transfected with 20 nM of control (Ctrl) or PP2Ac siRNA for 48 hours. (B) A549 cells were treated with 20 µM CGP57380 for the given times. After the aforementioned treatments, the whole-cell protein lysates prepared from these cells were subjected to m⁷GTP pull-down and subsequent detection of the given proteins by Western blot analysis. (E) The given cell lines were transfected with 5 nM of control or PP2Ac siRNA for 48 hours. The cells were then subjected to preparation of whole-cell protein lysates and subsequent detection of the indicated proteins by Western blot analysis. LE indicates long exposure.