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. 1976 Feb;73(2):298–301. doi: 10.1073/pnas.73.2.298

Polypeptide chain initiation in eukaryotes: mechanism of formation of initiation complex.

C Nombela, N A Nombela, S Ochoa, B Safer, W F Anderson, W C Merrick
PMCID: PMC335894  PMID: 1061132

Abstract

Artemia salina ribosomal subunits and highly purified reticulocyte initiation factors (IF) are used to study the mechanism of formation of the puromycin-sensitive initiation complex Met-tRNAi-80S ribosome-AUG. A complex with equimolar amounts of 40S subunit, GTP, and Met-tRNAi is formed at low Mg2+ concentration with a requirement for IF-MP (homogeneous) but not AUG or other factors. An 80S complex is formed only upon the further addition of AUG, IF-M2A, and IF-M2B, but not of either factor alone. This complex contains no GTP or GDP. A 40S complex, which cannot be converted to an 80S one, is formed when the nonhydrolyzable analog GMPPCP is substituted for GTP. IF-M2A has no effect on the formation of this complex, but IF-M2B enhances its formation.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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