“DNA Binding Region” of BRCA1 Affects Genetic Stability through modulating the Intra-S-Phase Checkpoint

The breast cancer associated gene 1 (BRCA1) contains 3 domains: an N-terminal RING domain with ubiquitin E3 ligase activity, C-terminal BRCT protein interaction domain and a central region. RING and BRCT domains are well characterized, yet the function of the central region remains unclear. In this study, we identified an essential DNA binding region (DBR: 421-701 amino acids) within the central region of human BRCA1, and found that BRCA1 brings DNA together and preferably binds to splayed-arm DNA in a sequence-independent manner. To investigate the biological role of the DBR, we generated mouse ES cells, which lack the DBR (ΔDBR) by using the TALEN method. The ΔDBR cells exhibited decreased survival as compared to the wild type (WT) cells treated with a PARP inhibitor, however they have an intact ability to conduct DNA repair mediated by homologous recombination (HR). The ΔDBR cells continued to incorporate more EdU in the presence of hydroxyurea (HU), which causes replication stress and exhibited reduced viability than the WT cells. Moreover, phosphorylation of CHK1, which regulates the intra-S phase checkpoint, was moderately decreased in ΔDBR cells. These data suggest that DNA binding by BRCA1 affects the stability of DNA replication folks, resulting in weakened intra-S-phase checkpoint control in the ΔDBR cells. The ΔDBR cells also exhibited an increased number of abnormal chromosome structures as compared with WT cells, indicating that the ΔDBR cells have increased genetic instability. Thus, we demonstrated that the DBR of BRCA1 modulates genetic stability through the intra-S-phase checkpoint activated by replication stress.

[1]  Mads Thomassen,et al.  Association of type and location of BRCA1 and BRCA2 mutations with risk of breast and ovarian cancer. , 2015, JAMA.

[2]  Y. Pommier,et al.  SIRT1 Deacetylates TopBP1 and Modulates Intra-S-Phase Checkpoint and DNA Replication Origin Firing , 2014, International journal of biological sciences.

[3]  Ralph Scully,et al.  BRCA1 controls homologous recombination at Tus/Ter-stalled mammalian replication forks , 2014, Nature.

[4]  K. Cimprich,et al.  Causes and consequences of replication stress , 2013, Nature Cell Biology.

[5]  E. Rosen BRCA1 in the DNA damage response and at telomeres , 2013, Front. Genet..

[6]  Y. Kakeji,et al.  CtIP‐ and ATR‐dependent FANCJ phosphorylation in response to DNA strand breaks mediated by DNA replication , 2012, Genes to cells : devoted to molecular & cellular mechanisms.

[7]  V. Costanzo,et al.  Mechanisms of replication fork protection: a safeguard for genome stability , 2012, Critical reviews in biochemistry and molecular biology.

[8]  G. Hankins,et al.  Structure-Function of the Tumor Suppressor BRCA1 , 2012, Computational and structural biotechnology journal.

[9]  J. Glover,et al.  Impact of BRCA1 BRCT Domain Missense Substitutions on Phosphopeptide Recognition , 2011, Biochemistry.

[10]  Steven P Gygi,et al.  Akt–RSK–S6 Kinase Signaling Networks Activated by Oncogenic Receptor Tyrosine Kinases , 2010, Science Signaling.

[11]  T. Lyons,et al.  AKT regulates BRCA1 stability in response to hormone signaling , 2010, Molecular and Cellular Endocrinology.

[12]  S. J. Campbell,et al.  Comparison of the structures and peptide binding specificities of the BRCT domains of MDC1 and BRCA1. , 2010, Structure.

[13]  Junjie Chen,et al.  BRCA1 and its toolbox for the maintenance of genome integrity , 2010, Nature Reviews Molecular Cell Biology.

[14]  C. Arrowsmith,et al.  The Central Region of BRCA1 Binds Preferentially to Supercoiled DNA , 2009, Journal of biomolecular structure & dynamics.

[15]  R. Naseem,et al.  Analysis of the DNA Binding Activity of BRCA1 and Its Modulation by the Tumour Suppressor p53 , 2008, PloS one.

[16]  R. Berro,et al.  Functional consequences of cyclin D1/BRCA1 interaction in breast cancer cells , 2007, Oncogene.

[17]  J. Bartek,et al.  DNA damage checkpoints: from initiation to recovery or adaptation. , 2007, Current opinion in cell biology.

[18]  Weixian Lu,et al.  A time- and cost-efficient system for high-level protein production in mammalian cells. , 2006, Acta crystallographica. Section D, Biological crystallography.

[19]  N. Mailand,et al.  Claspin Operates Downstream of TopBP1 To Direct ATR Signaling towards Chk1 Activation , 2006, Molecular and Cellular Biology.

[20]  C. Deng,et al.  PARP-1 inhibitors: are they the long-sought genetically specific drugs for BRCA1/2-associated breast cancers? , 2006, International journal of medical sciences.

[21]  T. Jowitt,et al.  Mapping and conformational characterization of the DNA-binding region of the breast cancer susceptibility protein BRCA1. , 2006, The Biochemical journal.

[22]  C. Deng,et al.  BRCA1: cell cycle checkpoint, genetic instability, DNA damage response and cancer evolution , 2006, Nucleic acids research.

[23]  Cheryl H Arrowsmith,et al.  Characterization of segments from the central region of BRCA1: an intrinsically disordered scaffold for multiple protein-protein and protein-DNA interactions? , 2005, Journal of molecular biology.

[24]  J. Glover,et al.  Structural basis of phosphopeptide recognition by the BRCT domain of BRCA1 , 2004, Nature Structural &Molecular Biology.

[25]  Yuri L Lyubchenko,et al.  Silatrane-based surface chemistry for immobilization of DNA, protein-DNA complexes and other biological materials. , 2003, Ultramicroscopy.

[26]  Lawrence C. Brody,et al.  BRCA1 regulates the G2/M checkpoint by activating Chk1 kinase upon DNA damage , 2002, Nature Genetics.

[27]  Rachel E. Klevit,et al.  Structure of a BRCA1–BARD1 heterodimeric RING–RING complex , 2001, Nature Structural Biology.

[28]  Curtis C. Harris,et al.  Genetic interactions between tumor suppressors Brca1 and p53 in apoptosis, cell cycle and tumorigenesis , 2001, Nature Genetics.

[29]  Thomas W. Yang,et al.  Impaired DNA Damage Response in Cells Expressing an Exon 11-Deleted Murine Brca1 Variant That Localizes to Nuclear Foci , 2001, Molecular and Cellular Biology.

[30]  S. Elledge,et al.  Direct DNA binding by Brca1 , 2001, Proceedings of the National Academy of Sciences of the United States of America.

[31]  J. P. Henderson,et al.  Production of Brominating Intermediates by Myeloperoxidase , 2001, The Journal of Biological Chemistry.

[32]  B. Koller,et al.  Brca1 controls homology-directed DNA repair. , 1999, Molecular cell.

[33]  Thomas Ried,et al.  Conditional mutation of Brca1 in mammary epithelial cells results in blunted ductal morphogenesis and tumour formation , 1999, Nature Genetics.

[34]  X. Wang,et al.  Centrosome amplification and a defective G2-M cell cycle checkpoint induce genetic instability in BRCA1 exon 11 isoform-deficient cells. , 1999, Molecular cell.

[35]  C. Deng,et al.  A targeted disruption of the murine Brca1 gene causes γ-irradiation hypersensitivity and genetic instability , 1998, Oncogene.

[36]  E. McDermott,et al.  Hereditary breast cancer , 1997, The British journal of surgery.

[37]  Yonghong Xiao,et al.  Association of BRCA1 with Rad51 in Mitotic and Meiotic Cells , 1997, Cell.

[38]  A. Alberg,et al.  Epidemiology, prevention, and early detection of breast cancer , 1994, Current opinion in oncology.

[39]  Steven E. Bayer,et al.  A strong candidate for the breast and ovarian cancer susceptibility gene BRCA1. , 1994, Science.

[40]  J. Eastham,et al.  Clinical features and management of BRCA1 and BRCA2-associated prostate cancer. , 2014, Frontiers in bioscience.

[41]  S. Paul,et al.  The breast cancer susceptibility genes (BRCA) in breast and ovarian cancers. , 2014, Frontiers in bioscience.

[42]  C. Deng,et al.  Generation and analysis of Brca1 conditional knockout mice. , 2004, Methods in molecular biology.

[43]  G. Casey The BRCA1 and BRCA2 breast cancer genes. , 1997, Current opinion in oncology.