Direct visualization of translational GTPase factor pool formed around the archaeal ribosomal P-stalk by high-speed AFM
Open Access
- 7 December 2020
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America
- Vol. 117 (51), 32386-32394
- https://doi.org/10.1073/pnas.2018975117
Abstract
In translation elongation, two translational guanosine triphosphatase (trGTPase) factors EF1A and EF2 alternately bind to the ribosome and promote polypeptide elongation. The ribosomal stalk is a multimeric ribosomal protein complex which plays an essential role in the recruitment of EF1A and EF2 to the ribosome and their GTP hydrolysis for efficient and accurate translation elongation. However, due to the flexible nature of the ribosomal stalk, its structural dynamics and mechanism of action remain unclear. Here, we applied high-speed atomic force microscopy (HS-AFM) to directly visualize the action of the archaeal ribosomal heptameric stalk complex, aP0•(aP1•aP1)3 (P-stalk). HS-AFM movies clearly demonstrated the wobbling motion of the P-stalk on the large ribosomal subunit where the stalk base adopted two conformational states, a predicted canonical state, and a newly identified flipped state. Moreover, we showed that up to seven molecules of archaeal EF1A (aEF1A) and archaeal EF2 (aEF2) assembled around the ribosomal P-stalk, corresponding to the copy number of the common C-terminal factor-binding site of the P-stalk. These results provide visual evidence for the factor-pooling mechanism by the P-stalk within the ribosome and reveal that the ribosomal P-stalk promotes translation elongation by increasing the local concentration of translational GTPase factors.This publication has 57 references indexed in Scilit:
- The enigmatic ribosomal stalkQuarterly Reviews of Biophysics, 2018
- Structural Basis for Translation Factor Recruitment to the Eukaryotic/Archaeal RibosomesOnline Journal of Public Health Informatics, 2010
- What recent ribosome structures have revealed about the mechanism of translationNature, 2009
- Recent mechanistic insights into eukaryotic ribosomesCurrent Opinion in Cell Biology, 2009
- Three Binding Sites for Stalk Protein Dimers Are Generally Present in Ribosomes from Archaeal OrganismOnline Journal of Public Health Informatics, 2007
- A Mode of Assembly of P0, P1, and P2 Proteins at the GTPase-associated Center in Animal RibosomeOnline Journal of Public Health Informatics, 2005
- Structural Basis for the Function of the Ribosomal L7/12 Stalk in Factor Binding and GTPase ActivationCell, 2005
- An Elongation Factor G-Induced Ribosome Rearrangement Precedes tRNA-mRNA TranslocationMolecular Cell, 2003
- GTPase Activation of Elongation Factors Tu and G on the RibosomeBiochemistry, 2002
- Initial Binding of the Elongation Factor Tu·GTP·Aminoacyl-tRNA Complex Preceding Codon Recognition on the RibosomeOnline Journal of Public Health Informatics, 1996