Filament formation by metabolic enzymes is a specific adaptation to an advanced state of cellular starvation
- Max Planck Institute of Molecular Cell Biology and Genetics, Germany
- Helmholtz Institute Dresden-Rossendorf, Germany
Abstract
One of the key questions in biology is how the metabolism of a cell responds to changes in the environment. In budding yeast, starvation causes a drop in intracellular pH, but the functional role of this pH change is not well understood. Here, we show that the enzyme glutamine synthetase (Gln1) forms filaments at low pH and that filament formation leads to enzymatic inactivation. Filament formation by Gln1 is a highly cooperative process, strongly dependent on macromolecular crowding, and involves back-to-back stacking of cylindrical homo-decamers into filaments that associate laterally to form higher order fibrils. Other metabolic enzymes also assemble into filaments at low pH. Hence, we propose that filament formation is a general mechanism to inactivate and store key metabolic enzymes during a state of advanced cellular starvation. These findings have broad implications for understanding the interplay between nutritional stress, the metabolism and the physical organization of a cell.
Article and author information
Author details
Reviewing Editor
- Jeffery W Kelly, Scripps Research Institute, United States
Version history
- Received: January 27, 2014
- Accepted: April 10, 2014
- Accepted Manuscript published: April 25, 2014 (version 1)
- Version of Record published: May 6, 2014 (version 2)
Copyright
© 2014, Petrovska et al.
This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.
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Filament formation by metabolic enzymes is a specific adaptation to an advanced state of cellular starvation
eLife 3:e02409.
https://doi.org/10.7554/eLife.02409
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