Genetic analysis of L123 of the tRNA-mimicking eukaryote release factor eRF1, an amino acid residue critical for discrimination of stop codons.

ABSTRACT: In eukaryotes, the tRNA-mimicking polypeptide-chain release factor, eRF1, decodes stop codons on the ribosome in a complex with eRF3; this complex exhibits striking structural similarity to the tRNA-eEF1A-GTP complex. Although amino acid residues or motifs of eRF1 that are critical for stop codon discrimination have been identified, the details of the molecular mechanisms involved in the function of the ribosomal decoding site remain obscure. Here, we report analyses of the position-123 amino acid of eRF1 (L123 in Saccharomyces cerevisiae eRF1), a residue that is phylogenetically conserved among species with canonical and variant genetic codes. In vivo readthrough efficiency analysis and genetic growth complementation analysis of the residue-123 systematic mutants suggested that this amino

SUBMITTER: Saito K 

PROVIDER: S-EPMC4482090 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature