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eIF-4E is a eukaryotic translation initiation factor involved in directing ribosomes to the cap structure of mRNAs. It exists in two forms: as a free form (25 kDa) and as part of a multiprotein complex eIF-4F (1). eIF-4E appears to be the least abundant of the initiation factors and acts as a rate-limiting step of initiation (2). Since translation is regulated by phosphorylation, eIF-4E phosphorylation at Ser 209 by MAPK signal-integrating kinase 1 (Mnk1) and kinase 2 (Mnk2) may directly regulate the rate of protein synthesis initiation (3). There is also evidence that eIF-4E can function as an oncogene (4-5).