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Updated: Jul 3, 2026
11:42
Iterative Optimization of DNA Duplexes for Crystallization of SeqA-DNA Complexes
Published on: November 1, 2012
RecR forms a ring-like tetramer that encircles dsDNA by forming a complex with RecF
Masayoshi Honda1, Tetsuro Fujisawa, Takehiko Shibata
1RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Nucleic Acids Research
|July 29, 2008
Summary
The RecFOR complex
Area of Science:
- Molecular Biology
- Structural Biology
- Biochemistry
Background:
- The RecFOR pathway is crucial for DNA repair.
- RecF and RecR proteins form a complex involved in RecA loading.
- The structure and DNA-binding mechanism of the RecFR complex were unknown.
Purpose of the Study:
- To elucidate the structure of the Thermus thermophilus RecFR complex.
- To understand the DNA-binding mechanism of the RecFR complex.
Main Methods:
- Size-exclusion chromatography
- Small-angle X-ray scattering
- Mutagenesis studies
Main Results:
- The Thermus thermophilus RecFR complex has a globular structure (4 ttRecR: 2 ttRecF).
- A central cavity suggests a ring-like ttRecR tetramer within the complex.
- Mutations disrupting ttRecR tetramerization or located within the ring reduce dsDNA binding.
Conclusions:
- The ring-like ttRecR tetramer is essential for tethering the RecFR complex to dsDNA.
- The RecFR complex, particularly the ttRecR ring, may function as a DNA clamp.
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