Eukaryotic translational termination efficiency is influenced by the 3' nucleotides within the ribosomal mRNA channel.

ABSTRACT: When a stop codon is at the 80S ribosomal A site, there are six nucleotides (+4 to +9) downstream that are inferred to be occupying the mRNA channel. We examined the influence of these downstream nucleotides on translation termination success or failure in mammalian cells at the three stop codons. The expected hierarchy in the intrinsic fidelity of the stop codons (UAA>UAG>>UGA) was observed, with highly influential effects on termination readthrough mediated by nucleotides at position +4 and position +8. A more complex influence was observed from the nucleotides at positions +5 and +6. The weakest termination contexts were most affected by increases or decreases in the concentration of the decoding release factor (eRF1), indicating that eRF1 binding to these signals was rate-limiting. Whe

SUBMITTER: Cridge AG 

PROVIDER: S-EPMC5829715 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature