Peptide chain release factor eRF1/aRF1 (IPR004403)

Short name: Peptide_chain-rel_eRF1/aRF1

Overlapping homologous superfamilies


Family relationships


Terminating protein synthesis on the ribosome requires the presence of a class I polypeptide chain release factor (RF) to induce peptidyl-tRNA hydrolysis. Bacteria possess two class I RFs; RF1 which recognises UAG and UAA, and RF2 which recognises UGA and UAA. Mitochondrial RFs are related structurally and functionally to those of bacteria. Eukaryotes posses only a single class 1 factor, eRF1, which recognises all three termination codons. Similarly, in all archaeal species where the complete sequence of the genome is available, only a single class I factor, aRF1, has been identified so far. The aRF1 family is highly homologous to the eRF1 family, indicating a common origin and ancestor molecule. The bacterial and mitochondrial class I RFs show no significant sequence similarity with their eukaryotic and archaeal counterparts and are considered to form a separate family. For more information see [PMID: 9179839, PMID: 10471834, PMID: 10788613].

This entry represents the eRF1 and aRF1 proteins.

GO terms

Biological Process

GO:0006415 translational termination

Molecular Function

GO:0003747 translation release factor activity

Cellular Component

GO:0005737 cytoplasm

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.