Coordinated conformational and compositional dynamics drive ribosome translocation
Open Access
- 28 April 2013
- journal article
- research article
- Published by Springer Science and Business Media LLC in Nature Structural & Molecular Biology
- Vol. 20 (6), 718-727
- https://doi.org/10.1038/nsmb.2567
Abstract
During translation elongation, the ribosome compositional factors elongation factor G (EF-G; encoded by fusA) and tRNA alternately bind to the ribosome to direct protein synthesis and regulate the conformation of the ribosome. Here, we use single-molecule fluorescence with zero-mode waveguides to directly correlate ribosome conformation and composition during multiple rounds of elongation at high factor concentrations in Escherichia coli. Our results show that EF-G bound to GTP (EF-G–GTP) continuously samples both rotational states of the ribosome, binding with higher affinity to the rotated state. Upon successful accommodation into the rotated ribosome, the EF-G–ribosome complex evolves through several rate-limiting conformational changes and the hydrolysis of GTP, which results in a transition back to the nonrotated state and in turn drives translocation and facilitates release of both EF-G–GDP and E-site tRNA. These experiments highlight the power of tracking single-molecule conformation and composition simultaneously in real time.Keywords
This publication has 51 references indexed in Scilit:
- The Impact of Aminoglycosides on the Dynamics of Translation ElongationCell Reports, 2013
- Conformational Changes of the Small Ribosomal Subunit During Elongation Factor G-dependent tRNA–mRNA TranslocationJournal of Molecular Biology, 2004
- tRNA selection and kinetic proofreading in translationNature Structural & Molecular Biology, 2004
- tRNA dynamics on the ribosome during translationProceedings of the National Academy of Sciences of the United States of America, 2004
- Peptidyl-tRNA Regulates the GTPase Activity of Translation FactorsCell, 2003
- Locking and Unlocking of Ribosomal MotionsCell, 2003
- An Elongation Factor G-Induced Ribosome Rearrangement Precedes tRNA-mRNA TranslocationMolecular Cell, 2003
- Conformationally Restricted Elongation Factor G Retains GTPase Activity but Is Inactive in Translocation on the RibosomeMolecular Cell, 2000
- Large-Scale Movement of Elongation Factor G and Extensive Conformational Change of the Ribosome during TranslocationCell, 2000
- A Model of the Functioning Ribosome: Locking and Unlocking of the Ribosome SubparticlesCold Spring Harbor Symposia on Quantitative Biology, 1969