Fanconi Anemia Is Characterized by Delayed Repair Kinetics of DNA Double-Strand Breaks

AbstractThe poly(ADP-ribose) polymerase, PARP1, plays a key role in maintaining genomic integrity by detecting DNA damage and mediating repair. γH2A.X is the primary histone marker for DNA double-strand breaks and PARP1 localizes to H2A.X-enriched chromatin damage sites, but the basis for this association is not clear. We characterize the kinetics of PARP1 binding to a variety of nucleosomes harbouring DNA double-strand breaks, which reveal that PARP1 associates faster with (γ)H2A.X- versus H2A-nucleosomes, resulting in a higher affinity for the former, which is maximal for γH2A.X-nucleosome that is also the activator eliciting the greatest poly-ADP-ribosylation catalytic efficiency. The enhanced activities with γH2A.X-nucleosome coincide with increased accessibility of the DNA termini resulting from the H2A.X-Ser139 phosphorylation. Indeed, H2A- and (γ)H2A.X-nucleosomes have distinct stability characteristics, which are rationalized by mutational analysis and (γ)H2A.X-nucleosome core crystal structures. This suggests that the γH2A.X epigenetic marker directly facilitates DNA repair by stabilizing PARP1 association and promoting catalysis.

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Repair Kinetics of Genomic Interstrand DNA Cross-Links: Evidence for DNA Double-Strand Break-Dependent Activation of the Fanconi Anemia/BRCA Pathway

Molecular and Cellular Biology ◽

10.1128/mcb.24.1.123-134.2004 ◽

2004 ◽

Vol 24 (1) ◽

pp. 123-134 ◽

Cited By ~ 170

Author(s):

Andreas Rothfuss ◽

Markus Grompe

Keyword(s):

Fanconi Anemia ◽

Strand Break ◽

S Phase ◽

Dna Double Strand Breaks ◽

Subsequent Formation ◽

Strand Breaks ◽

Dna Double Strand Break ◽

Cross Links ◽

Kinetics Of

ABSTRACT The detailed mechanisms of DNA interstrand cross-link (ICL) repair and the involvement of the Fanconi anemia (FA)/BRCA pathway in this process are not known. Present models suggest that recognition and repair of ICL in human cells occur primarily during the S phase. Here we provide evidence for a refined model in which ICLs are recognized and are rapidly incised by ERCC1/XPF independent of DNA replication. However, the incised ICLs are then processed further and DNA double-strand breaks (DSB) form exclusively in the S phase. FA cells are fully proficient in the sensing and incision of ICL as well as in the subsequent formation of DSB, suggesting a role of the FA/BRCA pathway downstream in ICL repair. In fact, activation of FANCD2 occurs slowly after ICL treatment and correlates with the appearance of DSB in the S phase. In contrast, activation is rapid after ionizing radiation, indicating that the FA/BRCA pathway is specifically activated upon DSB formation. Furthermore, the formation of FANCD2 foci is restricted to a subpopulation of cells, which can be labeled by bromodeoxyuridine incorporation. We therefore conclude that the FA/BRCA pathway, while being dispensable for the early events in ICL repair, is activated in S-phase cells after DSB have formed.

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RELATIONSHIP BETWEEN DNA DOUBLE-STRAND BREAKS AND KINETICS OF G2 CHROMATID ABERRATIONS

Radiation Research: A Twentieth-century Perspective ◽

10.1016/b978-0-12-168561-4.50164-5 ◽

1991 ◽

pp. 412

Author(s):

P.E. BRYANT ◽

P. SLIJEPCEVIC ◽

R.A.F. MACLEOD

Keyword(s):

Double Strand Breaks ◽

Dna Double Strand Breaks ◽

Strand Breaks ◽

Chromatid Aberrations ◽

Kinetics Of

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Fanconi Anemia FANCG Protein in Mitigating Radiation- and Enzyme-Induced DNA Double-Strand Breaks by Homologous Recombination in Vertebrate Cells

Molecular and Cellular Biology ◽

10.1128/mcb.23.15.5421-5430.2003 ◽

2003 ◽

Vol 23 (15) ◽

pp. 5421-5430 ◽

Cited By ~ 103

Author(s):

Kazuhiko Yamamoto ◽

Masamichi Ishiai ◽

Nobuko Matsushita ◽

Hiroshi Arakawa ◽

Jane E. Lamerdin ◽

...

Keyword(s):

Homologous Recombination ◽

Fanconi Anemia ◽

Cancer Susceptibility ◽

Bone Marrow Failure ◽

Chromosome Breakage ◽

Breast Cancer Susceptibility ◽

Double Strand Breaks ◽

Dna Double Strand Breaks ◽

Brca1 And Brca2 ◽

Strand Breaks

ABSTRACT The rare hereditary disorder Fanconi anemia (FA) is characterized by progressive bone marrow failure, congenital skeletal abnormality, elevated susceptibility to cancer, and cellular hypersensitivity to DNA cross-linking chemicals and sometimes other DNA-damaging agents. Molecular cloning identified six causative genes (FANCA, -C, -D2, -E, -F, and -G) encoding a multiprotein complex whose precise biochemical function remains elusive. Recent studies implicate this complex in DNA damage responses that are linked to the breast cancer susceptibility proteins BRCA1 and BRCA2. Mutations in BRCA2, which participates in homologous recombination (HR), are the underlying cause in some FA patients. To elucidate the roles of FA genes in HR, we disrupted the FANCG/XRCC9 locus in the chicken B-cell line DT40. FANCG-deficient DT40 cells resemble mammalian fancg mutants in that they are sensitive to killing by cisplatin and mitomycin C (MMC) and exhibit increased MMC and radiation-induced chromosome breakage. We find that the repair of I-SceI-induced chromosomal double-strand breaks (DSBs) by HR is decreased ∼9-fold in fancg cells compared with the parental and FANCG-complemented cells. In addition, the efficiency of gene targeting is mildly decreased in FANCG-deficient cells, but depends on the specific locus. We conclude that FANCG is required for efficient HR-mediated repair of at least some types of DSBs.

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Kinetics of recombinational hybrid formation in X-irradiated mammalian cells: a possible first step in the repair of DNA double-strand breaks

Mutation Research/DNA Repair Reports ◽

10.1016/0167-8817(84)90005-1 ◽

1984 ◽

Vol 132 (3-4) ◽

pp. 113-118 ◽

Cited By ~ 6

Author(s):

K. Fonck ◽

R. Barthel ◽

P.E. Bryant

Keyword(s):

Mammalian Cells ◽

Double Strand Breaks ◽

Dna Double Strand Breaks ◽

Strand Breaks ◽

Hybrid Formation ◽

Kinetics Of

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Repair kinetics of DNA double-strand breaks and incidence of apoptosis in mouse neural stem/progenitor cells and their differentiated neurons exposed to ionizing radiation

Journal of Radiation Research ◽

10.1093/jrr/rrx089 ◽

2018 ◽

Vol 59 (3) ◽

pp. 261-271 ◽

Cited By ~ 9

Author(s):

Hiroki Kashiwagi ◽

Kazunori Shiraishi ◽

Kenta Sakaguchi ◽

Tomoya Nakahama ◽

Seiji Kodama

Keyword(s):

Ionizing Radiation ◽

Progenitor Cells ◽

Double Strand Breaks ◽

Dna Double Strand Breaks ◽

Strand Breaks ◽

Neural Stem Progenitor Cells ◽

Kinetics Of

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Compromised repair of radiation-induced DNA double-strand breaks in Fanconi anemia fibroblasts in G2

DNA Repair ◽

10.1016/j.dnarep.2020.102992 ◽

2020 ◽

Vol 96 ◽

pp. 102992

Author(s):

Sebastian Zahnreich ◽

Britta Weber ◽

Gundula Rösch ◽

Detlev Schindler ◽

Heinz Schmidberger

Keyword(s):

Fanconi Anemia ◽

Double Strand Breaks ◽

Dna Double Strand Breaks ◽

Strand Breaks ◽

Radiation Induced

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Repair Kinetics of DNA Double Strand Breaks Induced by Simulated Space Radiation

Life ◽

10.3390/life10120341 ◽

2020 ◽

Vol 10 (12) ◽

pp. 341

Author(s):

Takashi Oizumi ◽

Rieko Ohno ◽

Souichiro Yamabe ◽

Tomoo Funayama ◽

Asako J. Nakamura

Keyword(s):

Dna Damage ◽

Ion Irradiation ◽

Space Radiation ◽

Double Strand Breaks ◽

Dependent Manner ◽

Dna Double Strand Breaks ◽

Dsb Repair ◽

Strand Breaks ◽

Carbon Ion ◽

Kinetics Of

Radiation is unavoidable in space. Energetic particles in space radiation are reported to induce cluster DNA damage that is difficult to repair. In this study, normal human fibroblasts were irradiated with components of space radiation such as proton, helium, or carbon ion beams. Immunostaining for γ-H2AX and 53BP1 was performed over time to evaluate the kinetics of DNA damage repair. Our data clearly show that the repair kinetics of DNA double strand breaks (DSBs) induced by carbon ion irradiation, which has a high linear energy transfer (LET), are significantly slower than those of proton and helium ion irradiation. Mixed irradiation with carbon ions, followed by helium ions, did not have an additive effect on the DSB repair kinetics. Interestingly, the mean γ-H2AX focus size was shown to increase with LET, suggesting that the delay in repair kinetics was due to damage that is more complex. Further, the 53BP1 focus size also increased in an LET-dependent manner. Repair of DSBs, characterized by large 53BP1 foci, was a slow process within the biphasic kinetics of DSB repair, suggesting non-homologous end joining with error-prone end resection. Our data suggest that the biological effects of space radiation may be significantly influenced by the dose as well as the type of radiation exposure.

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