Structural basis for ribosome recycling by RRF and tRNA

Dejian Zhou, Takehito Tanzawa, Jinzhong Lin, Matthieu G. Gagnon

Research output: Contribution to journalArticle

Abstract

The bacterial ribosome is recycled into subunits by two conserved proteins, elongation factor G (EF-G) and the ribosome recycling factor (RRF). The molecular basis for ribosome recycling by RRF and EF-G remains unclear. Here, we report the crystal structure of a posttermination Thermus thermophilus 70S ribosome complexed with EF-G, RRF and two transfer RNAs at a resolution of 3.5 Å. The deacylated tRNA in the peptidyl (P) site moves into a previously unsuspected state of binding (peptidyl/recycling, p/R) that is analogous to that seen during initiation. The terminal end of the p/R-tRNA forms nonfavorable contacts with the 50S subunit while RRF wedges next to central inter-subunit bridges, illuminating the active roles of tRNA and RRF in dissociation of ribosomal subunits. The structure uncovers a missing snapshot of tRNA as it transits between the P and exit (E) sites, providing insights into the mechanisms of ribosome recycling and tRNA translocation.

Original languageEnglish (US)
Pages (from-to)25-32
Number of pages8
JournalNature Structural and Molecular Biology
Volume27
Issue number1
DOIs
StatePublished - Jan 1 2020

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ASJC Scopus subject areas

  • Structural Biology
  • Molecular Biology

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