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Chromatin remodeling at DNA double-strand breaks.
Brendan D Price1, Alan D D'Andrea
1Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA.
Cell
|March 19, 2013
Summary
DNA double-strand breaks (DSBs) trigger chromatin remodeling, creating open structures essential for DNA repair. This process facilitates access for repair proteins, enabling efficient mammalian DSB repair.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- DNA double-strand breaks (DSBs) are critical DNA lesions.
- Ionizing radiation is a common source of DSBs.
- Chromatin structure can impede DNA repair processes.
Purpose of the Study:
- To review early chromatin-based events in DNA double-strand break repair.
- To understand how chromatin architecture influences DNA damage response.
- To highlight mechanisms facilitating mammalian DSB repair.
Main Methods:
- Literature review of chromatin remodeling and DNA repair.
- Analysis of posttranslational modifications of nucleosomes.
- Examination of DNA-repair protein recruitment to DSBs.
Main Results:
- Chromatin remodeling creates open, relaxed structures at DSBs.
- Nucleosome packing and chromatin architecture present challenges to repair.
- Early chromatin events are crucial for DNA-repair machinery access.
Conclusions:
- Relaxed chromatin structures are vital for efficient DSB repair.
- Overcoming chromatin barriers facilitates DNA repair protein access.
- Understanding these early events is key to mammalian DSB repair mechanisms.
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