Elongation factors (EF) facilitate translational elongation during the formation of peptide bonds in the ribosome. EF-selB is selenocysteine-specific EF. EF-Tu or EF 1-α (elongation factor thermo unstable) is a prokaryotic EF. EF-Tu contributes to translational accuracy. It catalyzes the addition of aminoacyl tRNA.
EF-Ts or EF 1-β (elongation factor thermo stable) catalyzes the release of GDP from EF-Tu. EF-G translocates the peptidyl tRNA from the A site to the P site while moving the mRNA through the ribosome. EF-SII helps RNA polymerase II to bypass blocks to elongation. EF-ELL2 enhances polyadenylation and exon skipping with the gene encoding the immunoglobulin heavy-chain complex. EF-GreA or GreB are cleavage factors allowing the resumption of elongation. EF-NusA recruits translesion DNA polymerases to gaps encountered during translation. EF-P alters the ribosome affinity to aminoacyl-tRNA. EF-1 gamma acts during the delivery of aminoacyl tRNA to the ribosome. EF-2 promotes the translocation of the nascent protein chain from the A site to the P site on the ribosome. EF-3 is unique EF in fungi hence it provides an anti-fungal drug target. EF Spt4, Spt5, Spt6 are conserved among eukaryotes. They modulate the chromatin structure. EF-CA150 is believed to play a role in coupling transcription and splicing. The elongin B and C complex is involved in the proteasomal degredation of target proteins.
For EF-3 see HEAT Repeat
For EF-SelB see SelB.
3D structures of elongation factor
Updated on 24-November-2014
