The GTPase Nog1 co-ordinates assembly, maturation and quality control of distant ribosomal functional centers
- University of Zürich, Switzerland
- ETH Zürich, Switzerland
Abstract
Eukaryotic ribosome precursors acquire translation competence in the cytoplasm through stepwise release of bound assembly factors, and proofreading of their functional centers. In case of the pre-60S, these steps include removal of placeholders Rlp24, Arx1 and Mrt4 that prevent premature loading of the ribosomal protein eL24, the protein-folding machinery at the polypeptide exit tunnel (PET), and the ribosomal stalk, respectively. Here, we reveal that sequential ATPase and GTPase activities license release factors Rei1 and Yvh1 to trigger Arx1 and Mrt4 removal. Drg1-ATPase activity removes Rlp24 from the GTPase Nog1 on the pre-60S; consequently, the C-terminal tail of Nog1 is extracted from the PET. These events enable Rei1 to probe PET integrity, and catalyze Arx1 release. Concomitantly, Nog1 eviction from the pre-60S permits peptidyl transferase center maturation, and Yvh1 to mediate Mrt4 release for stalk assembly. Thus, Nog1 co-ordinates assembly, maturation and quality control of distant functional centers during ribosome formation.
Data availability
The mass spectrometry data reported in this study has been deposited into the ProteomXchange Consortium via the PRIDE partner repository with dataset identifier PXD011382.
Article and author information
Author details
Daniela Portugal-Calisto
Funding
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Vikram G Panse
H2020 European Research Council (EURIBIO)
- Vikram G Panse
Novartis Stiftung für Medizinisch-Biologische Forschung
- Vikram G Panse
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Klingauf-Nerurkar et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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The GTPase Nog1 co-ordinates assembly, maturation and quality control of distant ribosomal functional centers
eLife 9:e52474.
https://doi.org/10.7554/eLife.52474
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