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Updated: May 16, 2026
11:04
Evaluation of the Impact of Protein Aggregation on Cellular Oxidative Stress in Yeast
Published on: June 23, 2018
Aneuploidy causes proteotoxic stress in yeast
Ana B Oromendia1, Stacie E Dodgson, Angelika Amon
1Koch Institute for Integrative Cancer Research, Department of Biology, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02138, USA.
Genes & Development
|December 11, 2012
Summary
Aneuploid yeast cells experience proteotoxic stress, leading to protein aggregation due to compromised protein quality control systems. This link between aneuploidy and protein aggregates may impact diseases like cancer and neurodegeneration.
Area of Science:
- Cell Biology
- Genetics
- Biochemistry
Background:
- Aneuploidy, characterized by whole chromosome gains or losses, is poorly tolerated across eukaryotes.
- The physiological consequences of aneuploidy at the organismal and cellular levels remain largely uncharacterized.
Purpose of the Study:
- To investigate the cellular and physiological effects of aneuploidy.
- To explore the relationship between aneuploidy and protein homeostasis.
Main Methods:
- Utilized budding yeast as a model organism to study aneuploidy.
- Assessed protein aggregation of endogenous and ectopically expressed proteins.
- Examined the function of protein quality control systems, including the proteasome and Hsp90 chaperone family.
Main Results:
- Aneuploid yeast cells exhibit significant proteotoxic stress.
- Aneuploid strains show increased aggregation of both endogenous and misfolded proteins (e.g., polyglutamine stretches).
- Protein aggregation in aneuploid cells is associated with compromised proteasome and Hsp90 chaperone function.
Conclusions:
- Aneuploidy induces proteotoxic stress and protein aggregation in yeast.
- Impaired protein quality control mechanisms contribute to aggregate formation in aneuploid cells.
- The observed link between aneuploidy and protein aggregation has potential implications for understanding diseases such as cancer and neurodegenerative disorders.
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