MYC, BCL2, and BCL6 are eIF4E targets. (A) Cytosolic/nuclear ratio (left) and total mRNA (right) of BCL6, BCL2, MYC, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH; as control) transcripts in U2OS cells transfected with eIF4E plasmid (eIF4E-WT) or flag-vector as control. (B) Protein levels of BCL6, BCL2, MYC, actin (as control), and eIF4E in U2OS cells transfected with eIF4E plasmid (4E) or flag-vector (V). Endogenous eIF4E is marked with closed arrowhead and flagged eIF4E is marked with an open arrowhead. (C) Cytosolic/nuclear ratio of BCL6, BCL2, MYC, and GAPDH (as control) transcripts in U2OS cells transfected with siRNA for luciferase (as control) or siRNA for eIF4E. Protein levels of BCL6, BCL2, MYC, and eIF4E from the experiments are shown on the right. (D) Cartoon depicting loss of function caused by each mutant eIF4E construct used in subsequent experiment. (E) Cytosolic/nuclear ratio of BCL6, MYC, and BCL2 transcripts (GAPDH transcripts are shown as a control) and total transcript expression (right) of UOS2 cells transfected with green fluorescent protein (GFP) (as a vector control), wild-type eIF4E, and mutant eIF4E constructs eIF4E^W73A and eIF4E^S53A. (F) BCL6, MYC, BCL2, and eIF4E protein expression for cells shown in panel E. (G) eIF4E RIP fold enrichment of MYC, BCL2, BCL6, and GAPDH (negative control) mRNAs over input in U2OS cells. (H) Cytosolic/nuclear ratio of luciferase and GAPDH (as negative control) in U2OS cells transfected with luciferase gene with or without BCL6 3′UTR sequence. Total mRNA for the same conditions is shown on the right. ****P < .0001.