PMID: 27773676

Authors:

Gruner S, Peter D, Weber R, Wohlbold L, Chung MY, Weichenrieder O, Valkov E, Igreja C, Izaurralde E

Title:

The Structures of eIF4E-eIF4G Complexes Reveal an Extended Interface to Regulate Translation Initiation.

Journal:

Mol Cell. 2016 Oct 19. pii: S1097-2765(16)30569-X. doi:, 10.1016/j.molcel.2016.09.020.

Abstract:

Eukaryotic initiation factor 4G (eIF4G) plays a central role in translation initiation through its interactions with the cap-binding protein eIF4E. This interaction is a major drug target for repressing translation and is naturally regulated by 4E-binding proteins (4E-BPs). 4E-BPs and eIF4G compete for binding to the eIF4E dorsal surface via a shared canonical 4E-binding motif, but also contain auxiliary eIF4E-binding sequences, which were assumed to contact non-overlapping eIF4E surfaces. However, it is unknown how metazoan eIF4G auxiliary sequences bind eIF4E. Here, we describe crystal structures of human and Drosophila melanogaster eIF4E-eIF4G complexes, which unexpectedly reveal that the eIF4G auxiliary sequences bind to the lateral surface of eIF4E, using a similar mode to that of 4E-BPs. Our studies provide a molecular model of the eIF4E-eIF4G complex, shed light on the competition mechanism of 4E-BPs, and enable the rational design of selective eIF4G inhibitors to dampen dysregulated translation in disease.