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Escherichia coli RadD Protein Functionally Interacts with the Single-stranded DNA-binding Protein
Stefanie H Chen1, Rose T Byrne-Nash2, Michael M Cox2
1From the Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706 slchen3@wisc.edu.
The Journal of Biological Chemistry
|August 14, 2016
Summary
The bacterial RadD protein interacts with single-stranded DNA binding protein (SSB) to organize DNA repair complexes, particularly for double-strand breaks. This interaction is crucial for RadD
Area of Science:
- Molecular Biology
- DNA Repair Mechanisms
- Bacterial Protein Interactions
Background:
- Bacterial single-stranded DNA binding protein (SSB) organizes DNA repair complexes.
- The radD gene's role in radiation damage repair, especially DNA double-strand breaks, is unclear.
- RadD protein exhibits DNA-independent ATPase activity.
Purpose of the Study:
- To investigate the functional role of the bacterial RadD protein in DNA repair.
- To elucidate the interaction between RadD and SSB proteins in DNA repair processes.
Main Methods:
- Purification of RadD protein.
- Assay of RadD ATPase activity.
- Yeast two-hybrid assay for in vivo protein interaction.
- Ammonium sulfate co-precipitation for in vitro protein interaction.
Main Results:
- RadD protein possesses DNA-independent ATPase activity.
- SSB protein stimulates RadD's ATP hydrolytic rates via its C terminus.
- RadD and SSB proteins interact directly both in vivo and in vitro.
Conclusions:
- RadD protein likely functions in DNA repair by interacting with SSB.
- This interaction is proposed to occur at the site of DNA damage.
- SSB acts as an organizer for RadD's repair function, particularly for double-strand breaks.
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