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Updated: Dec 13, 2025
08:13
Manipulation and Analysis of Cell Cycle-Dependent Processes in Budding Yeast
Published on: September 26, 2025
343
Punctuated Aneuploidization of the Budding Yeast Genome
Lydia R Heasley1, Ruth A Watson1, Juan Lucas Argueso2
1Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado 80523.
Genetics
|August 6, 2020
Summary
Eukaryotic cells can rapidly evolve complex genomic alterations, including aneuploidy, through fast, unstable events rather than slow, progressive changes over generations.
Area of Science:
- Genetics
- Cell Biology
- Genomics
Background:
- Aneuploidy, or abnormal chromosome numbers, is common in eukaryotes like yeast and tumor cells.
- Genome evolution is typically viewed as a gradual process over many generations.
Purpose of the Study:
- To investigate the dynamics and speed of aneuploidy acquisition in diploid *Saccharomyces cerevisiae* (yeast) cells.
- To explore whether genomes can undergo rapid evolutionary modes.
Main Methods:
- Utilized diploid *Saccharomyces cerevisiae* cells.
- Selected for the loss of single chromosomes.
- Observed concomitant acquisition of additional, unselected aneuploidies.
Main Results:
- Cells selected for single chromosome loss frequently gained additional, unselected aneuploidies simultaneously.
- Observed a spectrum of genomic alterations, from single-chromosome events to complex, systemic changes involving multiple chromosomes.
- Systemic aneuploidy events were frequent and resulted in highly complex karyotypes.
Conclusions:
- Cells can achieve highly altered genomic configurations rapidly.
- Genomic instability can occur in temporally restricted episodes, leading to fast genome evolution.
- Complex aneuploidy patterns can arise quickly, challenging the notion of purely gradual genome evolution.
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