2P8X

Fitted structure of ADPR-eEF2 in the 80S:ADPR-eEF2:GDPNP cryo-EM reconstruction

Summary for 2P8X

• Entry DOI: 10.2210/pdb2p8x/pdb
• Related: 1K5X 1K5Y 2P8w 2P8y 2P8z
• EMDB information: 1343
• Descriptor: Elongation factor 2, Elongation factor Tu-B, ADENOSINE-5-DIPHOSPHORIBOSE, ... (4 entities in total)
• Functional Keywords: elongation, translocation, gtpase, 80s ribosome, translation
• Biological source: Saccharomyces cerevisiae (baker's yeast); More
• Total number of polymer chains: 2
• Total formula weight: 98459.95

Authors

Taylor, D.J.,Nilsson, J.,Merrill, A.R.,Andersen, G.R.,Nissen, P.,Frank, J. (deposition date: 2007-03-23, release date: 2007-05-08, Last modification date: 2019-12-18)

Primary citation

Taylor, D.J.,Nilsson, J.,Merrill, A.R.,Andersen, G.R.,Nissen, P.,Frank, J.
Structures of modified eEF2.80S ribosome complexes reveal the role of GTP hydrolysis in translocation.
Embo J., 26:2421-2431, 2007

PubMed Abstract: On the basis of kinetic data on ribosome protein synthesis, the mechanical energy for translocation of the mRNA-tRNA complex is thought to be provided by GTP hydrolysis of an elongation factor (eEF2 in eukaryotes, EF-G in bacteria). We have obtained cryo-EM reconstructions of eukaryotic ribosomes complexed with ADP-ribosylated eEF2 (ADPR-eEF2), before and after GTP hydrolysis, providing a structural basis for analyzing the GTPase-coupled mechanism of translocation. Using the ADP-ribosyl group as a distinct marker, we observe conformational changes of ADPR-eEF2 that are due strictly to GTP hydrolysis. These movements are likely representative of native eEF2 motions in a physiological context and are sufficient to uncouple the mRNA-tRNA complex from two universally conserved bases in the ribosomal decoding center (A1492 and A1493 in Escherichia coli) during translocation. Interpretation of these data provides a detailed two-step model of translocation that begins with the eEF2/EF-G binding-induced ratcheting motion of the small ribosomal subunit. GTP hydrolysis then uncouples the mRNA-tRNA complex from the decoding center so translocation of the mRNA-tRNA moiety may be completed by a head rotation of the small subunit.

PubMed: 17446867
DOI: 10.1038/sj.emboj.7601677

Experimental method

ELECTRON MICROSCOPY (9.7 Å)