Related Experiment Video
Updated: Sep 19, 2025
07:18
Gene-targeted Random Mutagenesis to Select Heterochromatin-destabilizing Proteasome Mutants in Fission Yeast
Published on: May 15, 2018
10.8K
A transient mutational burst occurs during yeast colony development.
Nicolas Agier1,2, Nina Vittorelli1,2,3, Louis Ollivier1,2,4
1Sorbonne Université, CNRS, Computational, Quantitative and Synthetic Biology, CQSB, F-75005, Paris, France.
Molecular Systems Biology
|June 9, 2025
Summary
Wild-type yeast colonies show surprisingly high double mutation rates, suggesting transient mutator cells drive genomic instability. These findings are crucial for understanding cancer and cellular adaptation.
Area of Science:
- Genetics
- Molecular Biology
- Genomics
Background:
- Understanding mutation accumulation is key to cellular adaptation and diseases like cancer.
- Mutator strains contribute significantly to genomic instability.
Purpose of the Study:
- To characterize the contribution of transient mutators to mutation accumulation in wild-type yeast.
- To investigate the mechanisms and genetic control of hypermutation events.
Main Methods:
- Measurement of single and double mutation rates (point mutations, duplications, translocations) in yeast colonies.
- Numerical simulations to model transient mutator subpopulations.
- Exploration of genetic factors influencing hypermutation, including replication stress and DNA damage tolerance pathways.
Main Results:
- Wild-type yeast exhibited double mutation rates up to 17 times higher than predicted by single mutation rates.
- Identified transient mutator phenotypes in genetically normal cells, with mutations accumulating in bursts.
- Demonstrated that replication stress and DNA damage tolerance pathways modulate excess double mutant formation.
Conclusions:
- Transient mutator subpopulations play a significant role in generating genomic instability.
- These mutators contribute to the overall mutational load in growing populations.
- Findings provide insights into mechanisms underlying adaptation and disease development.
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