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Updated: Jun 17, 2026
08:12
High-throughput Screening for Protein-based Inheritance in S. cerevisiae
Published on: August 8, 2017
Prions, protein homeostasis, and phenotypic diversity
Randal Halfmann1, Simon Alberti, Susan Lindquist
1Whitehead Institute for Biomedical Research, Cambridge, MA, USA.
Trends in Cell Biology
|January 15, 2010
Summary
Prions, or protein-based molecular memories, are common in yeast and help populations adapt to stress. These heritable traits diversify yeast, potentially speeding up evolution and the development of new characteristics.
Area of Science:
- Molecular biology
- Genetics
- Evolutionary biology
Background:
- Prions are protein aggregates traditionally linked to mammalian diseases.
- Fungal prions represent a distinct class of protein-based genetic elements.
- Recent research suggests prions may be more prevalent in yeast than previously thought.
Purpose of the Study:
- To explore the role of prions in yeast adaptation and evolution.
- To investigate prions as molecular memories and bet-hedging devices.
- To highlight the significance of prion-driven phenotypic diversity.
Main Methods:
- Literature review and synthesis of recent findings on yeast prions.
- Analysis of prion-induced heritable changes in yeast phenotypes.
- Exploration of the relationship between environmental stress and prion activity.
Main Results:
- Fungal prions can alter genotype-phenotype relationships in a heritable manner.
- Prion prevalence in yeast may be underestimated.
- Prion-driven diversity is enhanced under stress and through prion maturation.
Conclusions:
- Yeast prions function as bet-hedging strategies, promoting adaptation to stressful conditions.
- Prions can accelerate the evolution of novel traits in yeast populations.
- Prions represent a significant, yet underappreciated, factor in fungal evolution.
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