InterPro domain: IPR036433

Translation elongation factors are responsible for two main processes during protein synthesis on the ribosome [ 1 , 2 , 3 ]. 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.

Elongation factor EF1B (also known as EF-Ts or EF-1beta/gamma/delta) is a nucleotide exchange factor that is required to regenerate EF1A from its inactive form (EF1A-GDP) to its active form (EF1A-GTP). EF1A is then ready to interact with a new aminoacyl-tRNA to begin the cycle again. EF1B is more complex in eukaryotes than in bacteria, and can consist of three subunits: EF1B-alpha (or EF-1beta), EF1B-gamma (or EF-1gamma) and EF1B-beta (or EF-1delta) [ 4 ].

This entry represents a conserved domain superfamily. This domain is usually found near the C terminus of EF1B-gamma chains, a peptide of 410-440 residues. The gamma chain appears to play a role in anchoring the EF1B complex to the beta and delta chains and to other cellular components.

1. Structural studies of eukaryotic elongation factors. Cold Spring Harb. Symp. Quant. Biol. 66, 425-37
2. Elongation factors on the ribosome. Curr. Opin. Struct. Biol. 15, 349-54
3. Elongation factors in protein biosynthesis. Trends Biochem. Sci. 28, 434-41