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Joined 2026-09-21 Message
Incoming links: Release factor
Release factor 2026-10-18
A release factor is a protein involved in terminating biological translation and releasing the completed polypeptide at a stop codon.[ref]
Biology 2e by Mary Ann Clark and others. §15.5, Translation, Elongation, and Termination, paragraph beginning “Termination of translation”
Stop codon Created 2026-10-14 Updated 2026-10-18
In the standard genetic code, UAA, UAG and UGA are stop codons: they signal termination of biological translation rather than an amino acid assignment. See Clark, Douglas and Choi: stop codons.
A stop codon supplies no additional amino acid residue. In the constructed AUG GCU UUC UGA example, replacing UGA by UAA preserves termination after the same three amino acid residues. Replacing UUC by UAA instead terminates after methionine and alanine. These are consequences of the stated genetic code, not measurements of expression efficiency.
At a standard stop codon, a release factor promotes release of the polypeptide from the ribosome. Ordinary delivery of an amino acid by transfer RNA does not supply a “stop amino acid”.[ref]
Biology 2e by Mary Ann Clark and others. §15.5, Translation, Elongation, and Termination, paragraph beginning “Termination of translation”: stop codons and release factors