The amino acid sequence of eukaryotic translation initiation factor 1 and its similarity to yeast initiation factor SUI1

Eukaryotic initiation factor eIF-1 was purified from rabbit reticulocytes. Amino acid sequence analysis revealed that the protein contained a blocked amino-terminus. After cleavage with the endoproteinase Asp-N, three peptides were sequenced. The obtained partial sequences were identical to sequences of SUI1ISO1, the human homologue of the yeast translation initiation factor SUI1. The SUI1 gene product was identified as a protein involved in the recognition of the protein synthesis initiation codon. A similar mode of action has been suggested for eIF-1.