Synergistic roles of the proteasome and autophagy for mitochondrial maintenance and chronological lifespan in fission yeast
Open Access
- 23 February 2010
- 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. 107 (8), 3540-3545
- https://doi.org/10.1073/pnas.0911055107
Abstract
Regulations of proliferation and quiescence in response to nutritional cues are important for medicine and basic biology. The fission yeast Schizosaccharomyces pombe serves as a model, owing to the shift of proliferating cells to the metabolically active quiescence (designate G0 phase hereafter) by responding to low nitrogen source. S. pombe G0 phase cells keep alive for months without growth and division. Nitrogen replenishment reinstates vegetative proliferation phase (designate VEG). Some 40 genes required for G0 maintenance were identified, but many more remain to be identified. We here show, using mutants, that the proteasome is required for maintaining G0 quiescence. Functional outcomes of proteasome in G0 and VEG phases appear to be distinct. Upon proteasome dysfunction, a number of antioxidant proteins and compounds responsive to ROS (reactive oxygen species) are produced. In addition, autophagy-mediated destruction of mitochondria occurs, which suppresses the loss of viability by eliminating ROS-generating mitochondria. These defensive responses are found in G0 but not in VEG, suggesting that the main function of proteasome in G0 phase homeostasis is to minimize ROS. Proteasome and autophagy are thus collaborative to support the lifespan of S. pombe G0 phase.This publication has 44 references indexed in Scilit:
- Mitochondria-Anchored Receptor Atg32 Mediates Degradation of Mitochondria via Selective AutophagyDevelopmental Cell, 2009
- Atg32 Is a Mitochondrial Protein that Confers Selectivity during MitophagyDevelopmental Cell, 2009
- Genetic control of cellular quiescence in S. pombeJournal of Cell Science, 2009
- Parkin is recruited selectively to impaired mitochondria and promotes their autophagyThe Journal of cell biology, 2008
- Reversible cytoplasmic localization of the proteasome in quiescent yeast cellsThe Journal of cell biology, 2008
- Persistent mitochondrial dysfunction and oxidative stress hinder neuronal cell recovery from reversible proteasome inhibitionApoptosis, 2008
- Rapamycin sensitivity of the Schizosaccharomyces pombe tor2 mutant and organization of two highly phosphorylated TOR complexes by specific and common subunitsGenes to Cells, 2007
- Two‐step, extensive alterations in the transcriptome from G0 arrest to cell division in Schizosaccharomyces pombeGenes to Cells, 2007
- Regulation of Nuclear Proteasome by Rhp6/Ubc2 through Ubiquitination and Destruction of the Sensor and Anchor Cut8Cell, 2005
- [56] Molecular genetic analysis of fission yeast Schizosaccharomyces pombeMethods in Enzymology, 1991