4qjs

Publication Abstract from PubMed

Elongation factor 4 (EF4/LepA) is a highly conserved guanosine triphosphatase translation factor. It was shown to promote back-translocation of tRNAs on posttranslocational ribosome complexes and to compete with elongation factor G for interaction with pretranslocational ribosomes, inhibiting the elongation phase of protein synthesis. Here, we report a crystal structure of EF4-guanosine diphosphate bound to the Thermus thermophilus ribosome with a P-site tRNA at 2.9 angstroms resolution. The C-terminal domain of EF4 reaches into the peptidyl transferase center and interacts with the acceptor stem of the peptidyl-tRNA in the P site. The ribosome is in an unusual state of ratcheting with the 30S subunit rotated clockwise relative to the 50S subunit, resulting in a remodeled decoding center. The structure is consistent with EF4 functioning either as a back-translocase or a ribosome sequester.

Ribosome structure. Crystal structure of elongation factor 4 bound to a clockwise ratcheted ribosome.,Gagnon MG, Lin J, Bulkley D, Steitz TA Science. 2014 Aug 8;345(6197):684-7. doi: 10.1126/science.1253525. PMID:25104389^[1]

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