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The eIF1A solution structure reveals a large RNA-binding surface important for scanning function.

J L Battiste·T V Pestova·C U Hellen·G Wagner
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Abstract

The translation initiation factor eIF1A is necessary for directing the 43S preinitiation complex from the 5' end of the mRNA to the initiation codon in a process termed scanning. We have determined the solution structure of human eIF1A, which reveals an oligonucleotide-binding (OB) fold and an additional domain. NMR titration experiments showed that eIF1A binds single-stranded RNA oligonucleotides in a site-specific, but non-sequence-specific manner, hinting at an mRNA interaction rather than specific rRNA or tRNA binding. The RNA binding surface extends over a large area covering the canonical OB fold binding site as well as a groove leading to the second domain. Site-directed mutations at multiple positions along the RNA-binding surface were defective in the ability to properly assemble preinitiation complexes at the AUG codon in vitro.

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Amino Acid SequenceArchaeaBacteriaBase SequenceBinding SitesCodonEukaryotic Initiation Factor-1HumansModels, MolecularMolecular Sequence DataNuclear Magnetic Resonance, BiomolecularOligoribonucleotidesPeptide Initiation FactorsProtein FoldingProtein Structure, SecondaryRNA, MessengerRecombinant ProteinsSaccharomyces cerevisiaeSequence AlignmentSequence Homology, Amino AcidSolutionsSubstrate SpecificityJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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J L Battiste, T V Pestova, C U Hellen, G Wagner. 2000. The eIF1A solution structure reveals a large RNA-binding surface important for scanning function.. https://doi.org/10.1016/s1097-2765(00)80407-4

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