Translation elongation factor EF1A, eukaryotic/archaeal (IPR004539)

Short name: Transl_elong_EF1A_euk/arc

Overlapping homologous superfamilies

Family relationships



Translation elongation factors are responsible for two main processes during protein synthesis on the ribosome [PMID: 12762045, PMID: 15922593, PMID: 12932732]. EF1A (or EF-Tu) is responsible for the selection and binding of the cognate aminoacyl-tRNA to the A-site (acceptor site) of the ribosome. EF2 (or EF-G) is responsible for the translocation of the peptidyl-tRNA from the A-site to the P-site (peptidyl-tRNA site) of the ribosome, thereby freeing the A-site for the next aminoacyl-tRNA to bind. Elongation factors are responsible for achieving accuracy of translation and both EF1A and EF2 are remarkably conserved throughout evolution.

EF1A (also known as EF-1alpha or EF-Tu) is a G-protein. It forms a ternary complex of EF1A-GTP-aminoacyltRNA. The binding of aminoacyl-tRNA stimulates GTP hydrolysis by EF1A, causing a conformational change in EF1A that causes EF1A-GDP to detach from the ribosome, leaving the aminoacyl-tRNA attached at the A-site. Only the cognate aminoacyl-tRNA can induce the required conformational change in EF1A through its tight anticodon-codon binding [PMID: 15680978, PMID: 12102560]. EF1A-GDP is returned to its active state, EF1A-GTP, through the action of another elongation factor, EF1B (also known as EF-Ts or EF-1beta/gamma/delta).

This entry represents EF1A proteins from in eukaryotic (eEF1alpha) and archaeal (aEF1alpha) organisms, these proteins being more closely related to one another than to EF1A (or EF-Tu) from bacteria (IPR004541).

Archaeal EF1-alpha is not only involved in translation elongation. It interacts with Pelota, a mRNA surveillance protein involved in no-go mRNA decay and non-stop mRNA decay; and with RF1, a tRNA-mimicking protein which recognises stop codons and catalyses polypeptide-chain release. Through these interactions archaeal EF1-alpha also has a role in translational termination and mRNA surveillance pathways [PMID: 20974926].

GO terms

Biological Process

GO:0006414 translational elongation

Molecular Function

GO:0005525 GTP binding
GO:0003746 translation elongation factor activity

Cellular Component

No terms assigned in this category.

Contributing signatures

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