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Publication Abstract from PubMed

Elongation factor 4 (EF4) is a member of the family of ribosome-dependent translational GTPase (trGTPase) factors, along with elongation factor G (EF-G) and BPI-inducible protein A (BipA). Although EF4 is highly conserved in bacterial, mitochondrial, and chloroplast genomes, its exact biological function remains controversial. Here, we present the cryo-EM reconstitution of the GTP form of EF4 bound to the ribosome with P- and E-site tRNAs at 3.8 A resolution. Interestingly, our structure reveals an unrotated ribosome rather than a clockwise-rotated ribosome, as observed in the presence of EF4-GDP and P-site tRNA. In addition, we also observed an counterclockwise rotated form of the above complex at 5.7 A resolution. Taken together, our results shed light on the interactions formed between EF4, the ribosome, and the P-site tRNA and illuminate the GTPase activation mechanism at previously unresolved detail.

Structure of the GTP form of elongation factor 4 (EF4) bound to the ribosome.,Kumar V, Ero R, Ahmed T, Goh KJ, Zhan Y, Bhushan S, Gao YG J Biol Chem. 2016 May 2. pii: jbc.M116.725945. PMID:27137929^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.