Role of BRCA2 DNA-binding and C-terminal domain on its mobility and conformation in DNA repair
- Oncode Institute, Erasmus MC Cancer Institute, Erasmus University Medical Center, Netherlands
Abstract
BRCA2 is an essential protein in genome maintenance, homologous recombination and replication fork protection. Its function includes multiple interaction partners and requires timely localization to relevant sites in the nucleus. We investigated the importance of the highly conserved DNA binding domain (DBD) and C-terminal domain (CTD) of BRCA2. We generated BRCA2 variants missing one or both domains in mouse ES cells and defined their contribution in HR function and dynamic localization in the nucleus, by single particle tracking of BRCA2 mobility. Changes in molecular architecture of BRCA2 induced by binding partners of purified BRCA2 was determined by scanning force microscopy. BRCA2 mobility and DNA damage-induced increase in the immobile fraction was largely unaffected by C-terminal deletions. The purified proteins missing CTD and/or DBD were defective in architectural changes correlating with reduced homologous recombination function in cells. These results emphasize BRCA2 activity at sites of damage beyond promoting RAD51 delivery.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1-5.
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Author details
Funding
Nederlandse Organisatie voor Wetenschappelijk Onderzoek
- Maarten W Paul
KWF Kankerbestrijding (10436)
- Arshdeep Sidhu
Convergence Health & Technology (CHT16)
- Maarten W Paul
KWF Kankerbestrijding (11143)
- Yongxin Liang
Cancer Genomics Centre
- Alex N Zelensky
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Paul et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Role of BRCA2 DNA-binding and C-terminal domain on its mobility and conformation in DNA repair
eLife 10:e67926.
https://doi.org/10.7554/eLife.67926
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