Translation elongation factor EFTu/EF1A, bacterial/organelle (IPR004541)

Short name: Transl_elong_EFTu/EF1A_bac/org

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 (or EF-Tu) proteins found primarily in bacteria, mitochondria and chloroplasts. Eukaryotic and archaeal EF1A (IPR004539) are excluded from this entry. When bound to GTP, EF-Tu can form a complex with any (correctly) aminoacylated tRNA except those for initiation and for selenocysteine, in which case EF-Tu is replaced by other factors [PMID: 16213500].

GO terms

Biological Process

GO:0006414 translational elongation

Molecular Function

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

Cellular Component

GO:0005622 intracellular

Contributing signatures

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