3JCE

Structure of Escherichia coli EF4 in pretranslocational ribosomes (Pre EF4)

This is a non-PDB format compatible entry.

Summary for 3JCE

• Entry DOI: 10.2210/pdb3jce/pdb
• Related: 3jcd
• EMDB information: 6550
• Descriptor: 16S ribosomal RNA, 30S ribosomal protein S11, 30S ribosomal protein S12, ... (60 entities in total)
• Functional Keywords: ribosome elongation, gtpase ef4, trna back-translocation, p-loop, ribosome
• Biological source: Escherichia coli K-12; More
• Total number of polymer chains: 58
• Total formula weight: 2314955.60

Authors

Zhang, D.,Yan, K.,Liu, G.,Song, G.,Luo, J.,Shi, Y.,Cheng, E.,Wu, S.,Jiang, T.,Low, J.,Gao, N.,Qin, Y. (deposition date: 2015-12-01, release date: 2016-01-13, Last modification date: 2024-06-05)

Primary citation

Zhang, D.,Yan, K.,Liu, G.,Song, G.,Luo, J.,Shi, Y.,Cheng, E.,Wu, S.,Jiang, T.,Lou, J.,Gao, N.,Qin, Y.
EF4 disengages the peptidyl-tRNA CCA end and facilitates back-translocation on the 70S ribosome
Nat. Struct. Mol. Biol., 23:125-131, 2016

PubMed Abstract: EF4 catalyzes tRNA back-translocation through an unknown mechanism. We report cryo-EM structures of Escherichia coli EF4 in post- and pretranslocational ribosomes (Post- and Pre-EF4) at 3.7- and 3.2-Å resolution, respectively. In Post-EF4, peptidyl-tRNA occupies the peptidyl (P) site, but the interaction between its CCA end and the P loop is disrupted. In Pre-EF4, the peptidyl-tRNA assumes a unique position near the aminoacyl (A) site, denoted the A site/EF4 bound (A/4) site, with a large displacement at its acceptor arm. Mutagenesis analyses suggest that a specific region in the EF4 C-terminal domain (CTD) interferes with base-pairing between the peptidyl-tRNA 3'-CCA and the P loop, whereas the EF4 CTD enhances peptidyl-tRNA interaction at the A/4 site. Therefore, EF4 induces back-translocation by disengaging the tRNA's CCA end from the peptidyl transferase center of the translating ribosome.

PubMed: 26809121
DOI: 10.1038/nsmb.3160

Experimental method

ELECTRON MICROSCOPY (3.2 Å)