Sequential Translation of Trinucleotide Codons for the Initiation and Termination of Protein Synthesis

Science  04 Oct 1968:
Vol. 162, Issue 3849, pp. 135-138
DOI: 10.1126/science.162.3849.135


Terminal events in protein synthesis were studied with trinucleotide codons. Initiator and terminator trinucleotides sequentially stimulate N-formyl-methionyl-tRNA binding to ribosomes and the release of free N-formyl-methionine from the ribosomal intermediate. The release factor discovered by Capecchi is also required. The trinucleotides UGA, UAA, and UAG were found to be terminator codons. This pattern of codon degeneracy has not been observed with other trinucleotides and transfer RNA.