Participation of initiation factors in the recruitment of mRNA to ribosomes.
The step of protein synthesis which is normally rate limiting, formation of the 48S initiation complex, is catalyzed by the group 4 initiation factors. Collectively they recognize the 7-methylguanosine-containing cap of mRNA, unwind mRNA secondary structure, and allow scanning for the initiation codon by the small ribosomal subunit. The activities of the eIF-4 polypeptides are modulated by phosphorylation. Recent studies shed new light on the mechanism of assembly of the 48S initiation complex and the effect of phosphorylation of one of the eIF-4 polypeptides, the cap-binding protein eIF-4E.
Rhoads
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Department of Biochemistry and Molecular Biology, Louisiana State University Medical Center, Shreveport 71130.
Joshi
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Minich
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D000818:Animals; D006801:Humans; D010448:Peptide Initiation Factors / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000096:biosynthesis; D012270:Ribosomes / Q000378:metabolism*
D010448:Peptide Initiation Factors; D012333:RNA, Messenger; D012269:Ribosomal Proteins