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Updated: Jun 2, 2026
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Detection of Homologous Recombination Intermediates via Proximity Ligation and Quantitative PCR in Saccharomyces cerevisiae
Published on: September 11, 2022
The budding yeast Mei5-Sae3 complex interacts with Rad51 and preferentially binds a DNA fork structure
Amanda F Say1, LeAnna L Ledford, Deepti Sharma
1Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA.
DNA Repair
|May 6, 2011
Summary
The Mei5-Sae3 complex binds specific DNA structures and interacts with Rad51, but lacks single-strand DNA annealing activity, distinguishing its role in homologous recombination from Rad52.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Meiotic homologous recombination is crucial for genetic diversity.
- Rad51 and Dmc1 form nucleoprotein filaments for DNA strand exchange.
- The Mei5-Sae3 complex acts as a recombination mediator, promoting Dmc1 nucleation.
Purpose of the Study:
- To biochemically characterize the Mei5-Sae3 complex.
- To elucidate the DNA binding preferences and protein interaction capabilities of Mei5-Sae3.
- To differentiate the function of Mei5-Sae3 from the Rad52 protein in homologous recombination.
Main Methods:
- Expression and purification of Mei5, Sae3, and the Mei5-Sae3 complex.
- Biochemical assays to determine DNA substrate binding specificity.
- Analysis of protein-protein interactions with Rad51.
- Assessment of recombination mediator and single-strand DNA annealing activities.
Main Results:
- Mei5-Sae3 preferentially binds fork-like DNA and 3' overhanging DNA.
- Mei5 protein confers DNA binding activity to the complex.
- Mei5-Sae3 interacts with Rad51 via Mei5's N-terminal domain.
- Mei5-Sae3 lacks recombination mediator activity for Rad51 and single-strand DNA annealing activity.
Conclusions:
- The Mei5-Sae3 complex exhibits distinct DNA binding and functional properties compared to Rad52.
- Mei5-Sae3's role in homologous recombination is differentiated from Rad51 mediation and single-strand DNA annealing.
- These findings clarify the specific functions of Mei5-Sae3 in the meiotic recombination pathway.
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