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Updated: Aug 8, 2026
06:24
Real-time Observation of the DNA Strand Exchange Reaction Mediated by Rad51
Published on: February 13, 2019
Multiple start codons and phosphorylation result in discrete Rad52 protein species
Adriana Antúnez de Mayolo1, Michael Lisby, Naz Erdeniz
1Department of Genetics & Development, Columbia University Medical Center, 701 West 168th Street, New York, NY 10032, USA.
Nucleic Acids Research
|May 19, 2006
Summary
The Saccharomyces cerevisiae RAD52 gene produces multiple protein forms from different start sites and through post-translational modification, including phosphorylation. These Rad52 proteins are essential for DNA repair and recombination processes.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- The Saccharomyces cerevisiae RAD52 gene exhibits multiple translation start sites.
- Protein blot analysis reveals several Rad52 protein species with varying electrophoretic mobilities.
Purpose of the Study:
- To elucidate the gene products encoded by the RAD52 gene.
- To investigate the causes of multiple Rad52 protein species and their functional significance.
Main Methods:
- Analysis of RAD52 gene sequence for potential start sites.
- Protein-blot analysis to detect Rad52 species.
- Investigation of post-translational modifications, including phosphorylation.
- Functional assays for recombination and DNA repair.
Main Results:
- Multiple Rad52 protein species arise from alternative start codon usage and post-translational modification.
- Rad52 undergoes both cell cycle-independent and cell cycle-dependent phosphorylation.
- Phosphorylation requires the Rad52 C terminus but not Rad51 interaction.
- Translation from the last three start sites is sufficient for spontaneous and induced DNA repair.
Conclusions:
- The RAD52 gene encodes multiple functional protein variants.
- Post-translational modifications, particularly phosphorylation, contribute to Rad52 heterogeneity.
- Rad52's role in DNA repair and recombination is robust, utilizing multiple translation initiation points.
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