Quantitative proteomic analysis reveals posttranslational responses to aneuploidy in yeast
Abstract
Aneuploidy causes severe developmental defects and is a near universal feature of tumor cells. Despite its profound effects, the cellular processes affected by aneuploidy are not well characterized. Here, we examined the consequences of aneuploidy on the proteome of aneuploid budding yeast strains. We show that although protein levels largely scale with gene copy number, subunits of multi-protein complexes are notable exceptions. Posttranslational mechanisms attenuate their expression when their encoding genes are in excess. Our proteomic analyses further revealed a novel aneuploidy-associated protein expression signature characteristic of altered metabolism and redox homeostasis. Indeed aneuploid cells harbor increased levels of reactive oxygen species (ROS). Interestingly, increased protein turnover attenuates ROS levels and this novel aneuploidy-associated signature and improves the fitness of most aneuploid strains. Our results show that aneuploidy causes alterations in metabolism and redox homeostasis. Cells respond to these alterations through both transcriptional and posttranscriptional mechanisms.
Article and author information
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Reviewing Editor
- Ivan Dikic, Goethe University, Germany
Version history
- Received: April 6, 2014
- Accepted: July 27, 2014
- Accepted Manuscript published: July 29, 2014 (version 1)
- Accepted Manuscript updated: July 30, 2014 (version 2)
- Version of Record published: August 12, 2014 (version 3)
Copyright
© 2014, Dephoure 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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