6fc3
From Proteopedia
Crystal structure of the eIF4E-p20 complex from Saccharomyces cerevisiae
Structural highlights
Function[IF4E_YEAST] Recognizes and binds the 7-methylguanosine-containing mRNA cap during an early step in the initiation of protein synthesis and facilitates ribosome binding by inducing the unwinding of the mRNAs secondary structures. [CAF20_YEAST] Acts as an inhibitor of cap-dependent translation. Competes with eIF4G1/TIF4631 and EAP1 for binding to eIF4E/TIF45 and interferes with the formation of the eIF4F complex, inhibiting translation and stabilizing mRNA. Binding affinity for eIF4E/TIF45 is 10-fold less than that of eIF4G1/TIF4631. Required for induction of pseudohyphal growth in response to nitrogen limitation, probably by regulating STE12 translation.[1] [2] [3] [4] [5] [6] [7] Publication Abstract from PubMedThe interaction of the eukaryotic initiation factor 4G (eIF4G) with the cap-binding protein eIF4E initiates cap-dependent translation and is regulated by the 4E-binding proteins (4E-BPs), which compete with eIF4G to repress translation. Metazoan eIF4G and 4E-BPs interact with eIF4E via canonical and non-canonical motifs that bind to the dorsal and lateral surface of eIF4E in a bipartite recognition mode. However, previous studies pointed to mechanistic differences in how fungi and metazoans regulate protein synthesis. We present crystal structures of the yeast eIF4E bound to two yeast 4E-BPs, p20 and Eap1p, as well as crystal structures of a fungal eIF4E-eIF4G complex. We demonstrate that the core principles of molecular recognition of eIF4E are in fact highly conserved among translational activators and repressors in eukaryotes. Finally, we reveal that highly specialized structural motifs do exist and serve to modulate the affinity of protein-protein interactions that regulate cap-dependent translation initiation in fungi. Structural motifs in eIF4G and 4E-BPs modulate their binding to eIF4E to regulate translation initiation in yeast.,Gruner S, Weber R, Peter D, Chung MY, Igreja C, Valkov E, Izaurralde E Nucleic Acids Res. 2018 Jul 27;46(13):6893-6908. doi: 10.1093/nar/gky542. PMID:30053226[8] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. Loading citation details.. Citations 3 reviews cite this structure No citations found References
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