Structural insights into ribosome recycling factor interactions with the 70S ribosome

JOURNAL OF MOLECULAR BIOLOGY

卷:376

Article

Pai, Raj D.¹  Zhang, Wen²  Schuwirth, Barbara S.²  Hirokawa, Go³  Kaji, Hideko³  Kaji, Akira⁴  Cate, Jamie H. D.^1,2,5 

[1] Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA

[2] Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA

[3] Thomas Jefferson Univ, Dept Biochem & Mol Biol, Philadelphia, PA 19107 USA

[4] Univ Penn, Sch Med, Dept Microbiol, Philadelphia, PA 19104 USA

[5] Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA

关键词: ribosome;    x-ray crystallography;    ribosome recycling factor;    protein synthesis;   

DOI  :  10.1016/j.jmb.2007.12.048

来源: Elsevier

【 摘 要 】

At the end of translation in bacteria, ribosome recycling factor (RRF) is used together with elongation factor G to recycle the 30S and 50S ribosomal subunits for the next round of translation. In x-ray crystal structures of RRF with the Escherichia coli 70S ribosome, RRF binds to the large ribosomal subunit in the cleft that contains the peptidyl transferase center. Upon binding of either E. coli or Thermus thermophilus RRF to the E. coli ribosome, the tip of ribosomal RNA helix 69 in the large subunit moves away from the small subunit toward RRF by 8 angstrom, thereby disrupting a key contact between the small and large ribosomal subunits termed bridge B2a. In the ribosome crystals, the ability of RRF to destabilize bridge B2a is influenced by crystal packing forces. Movement of helix 69 involves an ordered-to-disordered transition upon binding of RRF to the ribosome. The disruption of bridge B2a upon RRF binding to the ribosome seen in the present structures reveals one of the key roles that RRF plays in ribosome recycling, the dissociation of 70S ribosomes into subunits. The structures also reveal contacts between domain II of RRF and protein S12 in the 30S subunit that may also play a role in ribosome recycling. (c) 2008 Elsevier Ltd. All rights reserved.

【 授权许可】

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