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Elongation factor

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Structure of EF-Tu (cyan and magenta) with EF-Ts (green and yellow) (PDB entry 1efu)

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1 Function
2 3D structures of elongation factor

Function

Elongation factors (EF) facilitate translational elongation during the formation of peptide bonds in the ribosome.

EF-selB is selenocysteine-specific EF. See SelB
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^[1].
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 γ 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^[2].
EF-3 is a unique EF in fungi hence it provides an anti-fungal drug target. See HEAT Repeat
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.
Elongin complex or SIII activates elongation by RNA polymerase II by suppressing transient pausing of the enzyme^[3]. The complex is composed of elongin A, B and C. Elongin A (EloA) is the active component of the complex. Elongin B and C (EloBC) are the regulatory subunits of it. Von Hippel-Landau tumor suppressor protein (VHL) binds to EloBC and inhibits transcriptional elongation.
Negative EF (NELF) are involved in regulating the pausing of RNA Pol II polymerase transcripton^[4].

, or, more exactly (PDB entry 1efu).^[5]

3D structures of elongation factor

Elongation factor 3D structures

References

↑ Takeshita D, Tomita K. Assembly of Q{beta} viral RNA polymerase with host translational elongation factors EF-Tu and -Ts. Proc Natl Acad Sci U S A. 2010 Sep 7;107(36):15733-8. Epub 2010 Aug 23. PMID:20798060 doi:http://dx.doi.org/10.1073/pnas.1006559107
↑ Jorgensen R, Merrill AR, Andersen GR. The life and death of translation elongation factor 2. Biochem Soc Trans. 2006 Feb;34(Pt 1):1-6. PMID:16246167 doi:http://dx.doi.org/10.1042/BST20060001
↑ Aso T, Lane WS, Conaway JW, Conaway RC. Elongin (SIII): a multisubunit regulator of elongation by RNA polymerase II. Science. 1995 Sep 8;269(5229):1439-43. PMID:7660129
↑ Su BG, Vos SM. Distinct negative elongation factor conformations regulate RNA polymerase II promoter-proximal pausing. Mol Cell. 2024 Apr 4;84(7):1243-1256.e5. PMID:38401543 doi:10.1016/j.molcel.2024.01.023
↑ Kawashima T, Berthet-Colominas C, Wulff M, Cusack S, Leberman R. The structure of the Escherichia coli EF-Tu.EF-Ts complex at 2.5 A resolution. Nature. 1996 Feb 8;379(6565):511-8. PMID:8596629 doi:http://dx.doi.org/10.1038/379511a0