Skip to Main content Skip to Navigation
Journal articles

tmRNA-SmpB: a journey to the centre of the bacterial ribosome.

Abstract : Ribosomes mediate protein synthesis by decoding the information carried by messenger RNAs (mRNAs) and catalysing peptide bond formation between amino acids. When bacterial ribosomes stall on incomplete messages, the trans-translation quality control mechanism is activated by the transfer-messenger RNA bound to small protein B (tmRNA-SmpB ribonucleoprotein complex). Trans-translation liberates the stalled ribosomes and triggers degradation of the incomplete proteins. Here, we present the cryo-electron microscopy structures of tmRNA-SmpB accommodated or translocated into stalled ribosomes. Two atomic models for each state are proposed. This study reveals how tmRNA-SmpB crosses the ribosome and how, as the problematic mRNA is ejected, the tmRNA resume codon is placed onto the ribosomal decoding site by new contacts between SmpB and the nucleotides upstream of the tag-encoding sequence. This provides a structural basis for the transit of the large tmRNA-SmpB complex through the ribosome and for the means by which the tmRNA internal frame is set for translation to resume.
Complete list of metadatas

Cited literature [49 references]  Display  Hide  Download

https://www.hal.inserm.fr/inserm-00590774
Contributor : Hervé de Villemeur <>
Submitted on : Tuesday, April 9, 2013 - 2:04:05 PM
Last modification on : Saturday, June 6, 2020 - 8:46:05 AM

File

 Restricted access
To satisfy the distribution rights of the publisher, the document is embargoed until : jamais

Please log in to resquest access to the document

Identifiers

Citation

Félix Weis, Patrick Bron, Emmanuel Giudice, Jean-Paul Rolland, Daniel Thomas, et al.. tmRNA-SmpB: a journey to the centre of the bacterial ribosome.. EMBO Journal, EMBO Press, 2010, 29 (22), pp.3810-8. ⟨10.1038/emboj.2010.252⟩. ⟨inserm-00590774⟩

Share

Metrics

Record views

1181