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Updated: Jul 10, 2025
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Detection of Homologous Recombination Intermediates via Proximity Ligation and Quantitative PCR in Saccharomyces cerevisiae
Published on: September 11, 2022
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Splitting the yeast centromere by recombination
Stanislav G Kozmin1, Margaret Dominska1, Dao-Qiong Zheng2
1Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA.
Nucleic Acids Research
|November 23, 2023
Summary
Intercentromere recombination, a process involving DNA sequences at centromeres, occurs frequently in yeast. This recombination can lead to chromosome translocations and missegregation, suggesting negative genetic outcomes.
Area of Science:
- Genetics
- Molecular Biology
- Yeast Genetics
Background:
- Centromere fusions in human cancer cells are difficult to study due to complex satellite DNA.
- Investigating centromere recombination provides insights into genome stability.
Purpose of the Study:
- To develop and utilize methods for detecting intercentromere recombination in Saccharomyces cerevisiae.
- To elucidate the mechanisms and consequences of recombination between centromeres.
Main Methods:
- Development of novel methods to detect intercentromere recombination in yeast.
- Mapping recombination breakpoints to identify regions of homology.
- Whole-genome DNA sequencing to determine recombination mechanisms.
- Analysis of chromosome missegregation rates.
Main Results:
- Intercentromere recombination occurs at a rate of approximately 10^-8 per cell division between active or inactive centromeres.
- Recombination breakpoints are localized to a 43-base pair region of homology.
- Over 90% of events proceed via non-reciprocal recombination (gene conversion/break-induced replication).
- Intercentromere recombination can generate whole-arm translocations involving non-homologous chromosomes.
- Associated with frequent chromosome missegregation.
Conclusions:
- Intercentromere recombination is a significant source of genetic instability.
- The process can lead to chromosomal aberrations like translocations.
- Associated genetic instability has negative consequences for cell division and genome integrity.
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