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Updated: May 8, 2026
10:08
Genetic Mapping of Thermotolerance Differences Between Species of Saccharomyces Yeast via Genome-Wide Reciprocal Hemizygosity Analysis
Published on: August 12, 2019
Genome architecture is a selectable trait that can be maintained by antagonistic pleiotropy
Ana Teresa Avelar1, Lília Perfeito, Isabel Gordo
1Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Oeiras 2780-156, Portugal.
Nature Communications
|August 27, 2013
Summary
Chromosomal rearrangements are common in yeast and impact reproductive isolation. These mutations affect fitness, showing genotype-by-environment interactions and influencing gene expression.
Area of Science:
- Evolutionary genetics
- Population genetics
- Molecular evolution
Background:
- Chromosomal rearrangements are key drivers of genetic variation within and between species.
- Their direct impact on organismal fitness, however, remains largely unquantified.
- Understanding these effects is crucial for explaining their prevalence in natural populations.
Purpose of the Study:
- To quantify the fitness consequences of chromosomal rearrangements in natural isolates of Schizosaccharomyces pombe.
- To investigate the role of chromosomal rearrangements in reproductive isolation.
- To explore the impact of chromosomal structure variation on gene expression and fitness across different environments.
Main Methods:
- Construction of specific chromosomal rearrangements (two inversions, eight translocations) in Schizosaccharomyces pombe without altering coding sequences.
- Assessment of fitness effects on reproductive success during meiosis and growth rate during mitosis.
- Analysis of gene expression changes associated with chromosomal rearrangements.
- Evaluation of genotype-by-environment interactions on fitness.
Main Results:
- Chromosomal rearrangements are widespread in natural Schizosaccharomyces pombe isolates and contribute to reproductive isolation.
- These rearrangements significantly impact fitness, affecting both meiotic reproductive success and mitotic growth rates.
- A strong genotype-by-environment interaction was observed, indicating that the fitness effects of rearrangements are context-dependent.
- Rearrangements led to altered gene expression and instances of antagonistic pleiotropy, where a mutation has opposing effects on different fitness components.
Conclusions:
- This study provides the first quantification of fitness effects from de novo mutations causing chromosomal rearrangement variation.
- Chromosomal rearrangements contribute to reproductive isolation and possess complex fitness effects, including trade-offs and environmental dependencies.
- The findings suggest a mechanism for the maintenance of chromosomal rearrangements in natural populations, balancing deleterious and beneficial effects.
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