The eIF1A solution structure reveals a large RNA-binding surface important for scanning function.
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.
Battiste
J L
JL
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Pestova
T V
TV
Hellen
C U
CU
Wagner
G
G
D000595:Amino Acid Sequence; D001105:Archaea; D001419:Bacteria; D001483:Base Sequence; D001665:Binding Sites; D003062:Codon; D015977:Eukaryotic Initiation Factor-1; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D009843:Oligoribonucleotides / Q000737:chemistry* / Q000378:metabolism; D010448:Peptide Initiation Factors / Q000737:chemistry* / Q000378:metabolism*; D017510:Protein Folding; D017433:Protein Structure, Secondary; D012333:RNA, Messenger / Q000737:chemistry / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012441:Saccharomyces cerevisiae; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012996:Solutions; D013379:Substrate Specificity
D003062:Codon; D015977:Eukaryotic Initiation Factor-1; D009843:Oligoribonucleotides; D010448:Peptide Initiation Factors; D012333:RNA, Messenger; D011994:Recombinant Proteins; D012996:Solutions; C026022:eukaryotic peptide initiation factor-1A