Evidence for role of m7G5′-phosphate group in recognition of eukaryotic mRNA by initiation factor IF-M3

Abstract
7-Methylguanosine 5''-monophosphate inhibits protein synthesis in a fractionated, messenger-dependent rabbit reticulocyte cell-free system. This compound also inhibits binding of histone mRNA to reticulocyte ribosomes and interaction of VSV [vesicular stomatitis virus] mRNA and histone mRNA but not EMC [encephalomyocarditis] virus RNA with purified initiation factor IF-M3. These studies provide evidence that the role of 7-methylguanosine in the mechanism for initiation of eukaryotic mRNA translation may be related to specific recognition of mRNA by initiation factor IF-M3.