Supplementary Figure 1 from Attacking a Nexus of the Oncogenic Circuitry by Reversing Aberrant Eif4f-Mediated Translation

PDF file - 32K, Recognition of capped mRNA for translation initiation by the complex eIF4F. The eukaryotic translation initiation factor 4E (eIF4E), a 25 kDa phosphoprotein which directly contact to the cap structure, exists either as a monomer or as a subunit of the translation initiation complex eIF4F. When bound to capped messages, eIF4E control post-transcriptional gene expression in the nucleus, where it facilitates the nuclear export of some mRNAs, and in the cytoplasm, where it selectively activates mRNAs for their recruitment to ribosomes. The trimolecular complex eIF4F is essential for recruitment of capped transcripts to ribosomes and subsequent ribosome scanning. It consists of translational factors eIF4E, eIF4G and eIF4A and for the eIF4A cofactor eIF4B. There are two isoforms of translation initiation factor 4G, eIF4GI and eIF4GII that serve a docking function, with the amino terminal half binding to eIF4E, and the C-terminal half binding to eIF4A. The eIF4G family proteins also have recognition sites for several other peptides including for the poly (A) binding protein (PARP), which facilitates circularization of the eIF4F-mRNA complex. Translation initiation factor 4A functions as an ATP requiring helicase by unwinding the 5' region