1
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Xu MJ, Jordan PW. SMC5/6 Promotes Replication Fork Stability via Negative Regulation of the COP9 Signalosome. Int J Mol Sci 2024; 25:952. [PMID: 38256025 PMCID: PMC10815603 DOI: 10.3390/ijms25020952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/06/2024] [Accepted: 01/10/2024] [Indexed: 01/24/2024] Open
Abstract
It is widely accepted that DNA replication fork stalling is a common occurrence during cell proliferation, but there are robust mechanisms to alleviate this and ensure DNA replication is completed prior to chromosome segregation. The SMC5/6 complex has consistently been implicated in the maintenance of replication fork integrity. However, the essential role of the SMC5/6 complex during DNA replication in mammalian cells has not been elucidated. In this study, we investigate the molecular consequences of SMC5/6 loss at the replication fork in mouse embryonic stem cells (mESCs), employing the auxin-inducible degron (AID) system to deplete SMC5 acutely and reversibly in the defined cellular contexts of replication fork stall and restart. In SMC5-depleted cells, we identify a defect in the restart of stalled replication forks, underpinned by excess MRE11-mediated fork resection and a perturbed localization of fork protection factors to the stalled fork. Previously, we demonstrated a physical and functional interaction of SMC5/6 with the COP9 signalosome (CSN), a cullin deneddylase that enzymatically regulates cullin ring ligase (CRL) activity. Employing a combination of DNA fiber techniques, the AID system, small-molecule inhibition assays, and immunofluorescence microscopy analyses, we show that SMC5/6 promotes the localization of fork protection factors to stalled replication forks by negatively modulating the COP9 signalosome (CSN). We propose that the SMC5/6-mediated modulation of the CSN ensures that CRL activity and their roles in DNA replication fork stabilization are maintained to allow for efficient replication fork restart when a replication fork stall is alleviated.
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Affiliation(s)
- Michelle J. Xu
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Philip W. Jordan
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
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2
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Liu W, Polaczek P, Roubal I, Meng Y, Choe WC, Caron MC, Sedgeman C, Xi Y, Liu C, Wu Q, Zheng L, Masson JY, Shen B, Campbell J. FANCD2 and RAD51 recombinase directly inhibit DNA2 nuclease at stalled replication forks and FANCD2 acts as a novel RAD51 mediator in strand exchange to promote genome stability. Nucleic Acids Res 2023; 51:9144-9165. [PMID: 37526271 PMCID: PMC10516637 DOI: 10.1093/nar/gkad624] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 06/17/2023] [Accepted: 07/28/2023] [Indexed: 08/02/2023] Open
Abstract
FANCD2 protein, a key coordinator and effector of the interstrand crosslink repair pathway, is also required to prevent excessive nascent strand degradation at hydroxyurea-induced stalled forks. The RAD51 recombinase has also been implicated in regulation of resection at stalled replication forks. The mechanistic contributions of these proteins to fork protection are not well understood. Here, we used purified FANCD2 and RAD51 to study how each protein regulates DNA resection at stalled forks. We characterized three mechanisms of FANCD2-mediated fork protection: (1) The N-terminal domain of FANCD2 inhibits the essential DNA2 nuclease activity by directly binding to DNA2 accounting for over-resection in FANCD2 defective cells. (2) Independent of dimerization with FANCI, FANCD2 itself stabilizes RAD51 filaments to inhibit multiple nucleases, including DNA2, MRE11 and EXO1. (3) Unexpectedly, we uncovered a new FANCD2 function: by stabilizing RAD51 filaments, FANCD2 acts to stimulate the strand exchange activity of RAD51. Our work biochemically explains non-canonical mechanisms by which FANCD2 and RAD51 protect stalled forks. We propose a model in which the strand exchange activity of FANCD2 provides a simple molecular explanation for genetic interactions between FANCD2 and BRCA2 in the FA/BRCA fork protection pathway.
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Affiliation(s)
- Wenpeng Liu
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
- Colleges of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Piotr Polaczek
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
| | - Ivan Roubal
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
| | - Yuan Meng
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, 1500 East Duarte Road, Duarte, CA 91010-3000, USA
- Colleges of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Won-chae Choe
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
| | - Marie-Christine Caron
- Genome Stability Laboratory, CHU de Québec Research Center, HDQ Pavilion, Oncology Division, 9 McMahon, Québec City, QC G1R 3S3, Canada
| | - Carl A Sedgeman
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
| | - Yu Xi
- Colleges of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Changwei Liu
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, 1500 East Duarte Road, Duarte, CA 91010-3000, USA
- Colleges of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Qiong Wu
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, 1500 East Duarte Road, Duarte, CA 91010-3000, USA
| | - Li Zheng
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, 1500 East Duarte Road, Duarte, CA 91010-3000, USA
| | - Jean-Yves Masson
- Genome Stability Laboratory, CHU de Québec Research Center, HDQ Pavilion, Oncology Division, 9 McMahon, Québec City, QC G1R 3S3, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology; Laval University Cancer Research Center, Québec City, QC G1V 0A6, Canada
| | - Binghui Shen
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, 1500 East Duarte Road, Duarte, CA 91010-3000, USA
| | - Judith L Campbell
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
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3
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Airik M, Arbore H, Childs E, Huynh AB, Phua YL, Chen CW, Aird K, Bharathi S, Zhang B, Conlon P, Kmoch S, Kidd K, Bleyer AJ, Vockley J, Goetzman E, Wipf P, Airik R. Mitochondrial ROS Triggers KIN Pathogenesis in FAN1-Deficient Kidneys. Antioxidants (Basel) 2023; 12:900. [PMID: 37107275 PMCID: PMC10135478 DOI: 10.3390/antiox12040900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/02/2023] [Accepted: 04/03/2023] [Indexed: 04/29/2023] Open
Abstract
Karyomegalic interstitial nephritis (KIN) is a genetic adult-onset chronic kidney disease (CKD) characterized by genomic instability and mitotic abnormalities in the tubular epithelial cells. KIN is caused by recessive mutations in the FAN1 DNA repair enzyme. However, the endogenous source of DNA damage in FAN1/KIN kidneys has not been identified. Here we show, using FAN1-deficient human renal tubular epithelial cells (hRTECs) and FAN1-null mice as a model of KIN, that FAN1 kidney pathophysiology is triggered by hypersensitivity to endogenous reactive oxygen species (ROS), which cause chronic oxidative and double-strand DNA damage in the kidney tubular epithelial cells, accompanied by an intrinsic failure to repair DNA damage. Furthermore, persistent oxidative stress in FAN1-deficient RTECs and FAN1 kidneys caused mitochondrial deficiencies in oxidative phosphorylation and fatty acid oxidation. The administration of subclinical, low-dose cisplatin increased oxidative stress and aggravated mitochondrial dysfunction in FAN1-deficient kidneys, thereby exacerbating KIN pathophysiology. In contrast, treatment of FAN1 mice with a mitochondria-targeted ROS scavenger, JP4-039, attenuated oxidative stress and accumulation of DNA damage, mitigated tubular injury, and preserved kidney function in cisplatin-treated FAN1-null mice, demonstrating that endogenous oxygen stress is an important source of DNA damage in FAN1-deficient kidneys and a driver of KIN pathogenesis. Our findings indicate that therapeutic modulation of kidney oxidative stress may be a promising avenue to mitigate FAN1/KIN kidney pathophysiology and disease progression in patients.
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Affiliation(s)
- Merlin Airik
- Division of Nephrology, Department of Pediatrics, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Haley Arbore
- Division of Nephrology, Department of Pediatrics, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Elizabeth Childs
- Division of Nephrology, Department of Pediatrics, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Amy B. Huynh
- Division of Nephrology, Department of Pediatrics, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Yu Leng Phua
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Chi Wei Chen
- Department of Pharmacology & Chemical Biology and UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Katherine Aird
- Department of Pharmacology & Chemical Biology and UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Sivakama Bharathi
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine and UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Bob Zhang
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine and UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Peter Conlon
- Nephrology Department, Beaumont Hospital, D09 V2N0 Dublin, Ireland
| | - Stanislav Kmoch
- Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University, 128 08 Prague, Czech Republic
| | - Kendrah Kidd
- Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | | | - Jerry Vockley
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine and UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Eric Goetzman
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine and UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Peter Wipf
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Rannar Airik
- Division of Nephrology, Department of Pediatrics, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
- Department of Developmental Biology, University of Pittsburgh, Pittsburgh, PA 15224, USA
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4
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Kavlashvili T, Liu W, Mohamed TM, Cortez D, Dewar JM. Replication fork uncoupling causes nascent strand degradation and fork reversal. Nat Struct Mol Biol 2023; 30:115-124. [PMID: 36593312 PMCID: PMC9868089 DOI: 10.1038/s41594-022-00871-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 10/14/2022] [Indexed: 01/03/2023]
Abstract
Genotoxins cause nascent strand degradation (NSD) and fork reversal during DNA replication. NSD and fork reversal are crucial for genome stability and are exploited by chemotherapeutic approaches. However, it is unclear how NSD and fork reversal are triggered. Additionally, the fate of the replicative helicase during these processes is unknown. We developed a biochemical approach to study synchronous, localized NSD and fork reversal using Xenopus egg extracts and validated this approach with experiments in human cells. We show that replication fork uncoupling stimulates NSD of both nascent strands and progressive conversion of uncoupled forks to reversed forks. Notably, the replicative helicase remains bound during NSD and fork reversal. Unexpectedly, NSD occurs before and after fork reversal, indicating that multiple degradation steps take place. Overall, our data show that uncoupling causes NSD and fork reversal and elucidate key events that precede fork reversal.
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Affiliation(s)
- Tamar Kavlashvili
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Wenpeng Liu
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Taha M Mohamed
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - David Cortez
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - James M Dewar
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA.
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5
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MYC multimers shield stalled replication forks from RNA polymerase. Nature 2022; 612:148-155. [PMID: 36424410 DOI: 10.1038/s41586-022-05469-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/20/2022] [Indexed: 11/26/2022]
Abstract
Oncoproteins of the MYC family drive the development of numerous human tumours1. In unperturbed cells, MYC proteins bind to nearly all active promoters and control transcription by RNA polymerase II2,3. MYC proteins can also coordinate transcription with DNA replication4,5 and promote the repair of transcription-associated DNA damage6, but how they exert these mechanistically diverse functions is unknown. Here we show that MYC dissociates from many of its binding sites in active promoters and forms multimeric, often sphere-like structures in response to perturbation of transcription elongation, mRNA splicing or inhibition of the proteasome. Multimerization is accompanied by a global change in the MYC interactome towards proteins involved in transcription termination and RNA processing. MYC multimers accumulate on chromatin immediately adjacent to stalled replication forks and surround FANCD2, ATR and BRCA1 proteins, which are located at stalled forks7,8. MYC multimerization is triggered in a HUWE16 and ubiquitylation-dependent manner. At active promoters, MYC multimers block antisense transcription and stabilize FANCD2 association with chromatin. This limits DNA double strand break formation during S-phase, suggesting that the multimerization of MYC enables tumour cells to proliferate under stressful conditions.
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6
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Airik M, Phua YL, Huynh AB, McCourt BT, Rush BM, Tan RJ, Vockley J, Murray SL, Dorman A, Conlon PJ, Airik R. Persistent DNA damage underlies tubular cell polyploidization and progression to chronic kidney disease in kidneys deficient in the DNA repair protein FAN1. Kidney Int 2022; 102:1042-1056. [PMID: 35931300 PMCID: PMC9588672 DOI: 10.1016/j.kint.2022.07.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 06/24/2022] [Accepted: 07/06/2022] [Indexed: 12/14/2022]
Abstract
Defective DNA repair pathways contribute to the development of chronic kidney disease (CKD) in humans. However, the molecular mechanisms underlying DNA damage-induced CKD pathogenesis are not well understood. Here, we investigated the role of tubular cell DNA damage in the pathogenesis of CKD using mice in which the DNA repair protein Fan1 was knocked out. The phenotype of these mice is orthologous to the human DNA damage syndrome, karyomegalic interstitial nephritis (KIN). Inactivation of Fan1 in kidney proximal tubule cells sensitized the kidneys to genotoxic and obstructive injury characterized by replication stress and persistent DNA damage response activity. Accumulation of DNA damage in Fan1 tubular cells induced epithelial dedifferentiation and tubular injury. Characteristic to KIN, cells with chronic DNA damage failed to complete mitosis and underwent polyploidization. In vitro and in vivo studies showed that polyploidization was caused by the overexpression of DNA replication factors CDT1 and CDC6 in FAN1 deficient cells. Mechanistically, inhibiting DNA replication with Roscovitine reduced tubular injury, blocked the development of KIN and mitigated kidney function in these Fan1 knockout mice. Thus, our data delineate a mechanistic pathway by which persistent DNA damage in the kidney tubular cells leads to kidney injury and development of CKD. Furthermore, therapeutic modulation of cell cycle activity may provide an opportunity to mitigate the DNA damage response induced CKD progression.
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Affiliation(s)
- Merlin Airik
- Division of Nephrology, Department of Pediatrics, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Yu Leng Phua
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Amy B Huynh
- Division of Nephrology, Department of Pediatrics, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Blake T McCourt
- Division of Nephrology, Department of Pediatrics, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Brittney M Rush
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Roderick J Tan
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jerry Vockley
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Susan L Murray
- Department of Nephrology, Beaumont Hospital and Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Anthony Dorman
- Department of Nephrology, Beaumont Hospital and Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Peter J Conlon
- Department of Nephrology, Beaumont Hospital and Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Rannar Airik
- Division of Nephrology, Department of Pediatrics, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA; Department of Developmental Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
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7
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Clay DE, Jezuit EA, Montague RA, Fox DT. Conserved function of Drosophila Fancd2 monoubiquitination in response to double-strand DNA breaks. G3 (BETHESDA, MD.) 2022; 12:6589893. [PMID: 35595243 PMCID: PMC9339327 DOI: 10.1093/g3journal/jkac129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 05/12/2022] [Indexed: 11/12/2022]
Abstract
Fanconi anemia genes play key roles in metazoan DNA damage responses, and human FA mutations cause numerous disease phenotypes. In human cells, activating monoubiquitination of the Fanconi anemia protein Fancd2 occurs following diverse DNA damage stimuli. Monoubiquitinated Fancd2 forms nuclear foci to recruit additional repair factors. Fancd2 animal models to date have focused on molecular nulls or whole gene knockdown, leaving the specific in vivo role of monoubiquitination unclear. Using a point mutant in a conserved residue, we recently linked Drosophila Fancd2 monoubiquitination to a mitosis-specific DNA double-strand break response. In this context, we used CRISPR/Cas9 to generate the first animal model of an endogenous mutation in the conserved monoubiquitination site (fancd2K595R). Here, we expand upon our characterization of fancd2K595R. We also introduce and characterize additional Drosophila tools to study fancd2, including new mutant alleles and GFP-tagged rescue transgenes. Using these new reagents, we show the impact of Drosophila Fancd2 on organismal and cell viability, as well as on repair protein localization, in the presence or absence of double-strand breaks. These findings expand our understanding of Fanconi anemia gene function in vivo and provide useful reagents for DNA repair research.
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Affiliation(s)
- Delisa E Clay
- Department of Pharmacology and Cancer Biology, C318 Levine Science Research Center, Duke University Medical School, Durham, NC 27710, USA
| | - Erin A Jezuit
- Department of Pharmacology and Cancer Biology, C318 Levine Science Research Center, Duke University Medical School, Durham, NC 27710, USA
| | - Ruth A Montague
- Department of Pharmacology and Cancer Biology, C318 Levine Science Research Center, Duke University Medical School, Durham, NC 27710, USA
| | - Donald T Fox
- Corresponding author: Department of Pharmacology and Cancer Biology, C318 Levine Science Research Center, DUMC Box 3813, Duke University Medical School, Durham, NC 27710, USA.
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8
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Badra Fajardo N, Taraviras S, Lygerou Z. Fanconi anemia proteins and genome fragility: unraveling replication defects for cancer therapy. Trends Cancer 2022; 8:467-481. [DOI: 10.1016/j.trecan.2022.01.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 01/25/2022] [Indexed: 10/19/2022]
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9
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So A, Dardillac E, Muhammad A, Chailleux C, Sesma-Sanz L, Ragu S, Le Cam E, Canitrot Y, Masson J, Dupaigne P, Lopez BS, Guirouilh-Barbat J. OUP accepted manuscript. Nucleic Acids Res 2022; 50:2651-2666. [PMID: 35137208 PMCID: PMC8934640 DOI: 10.1093/nar/gkac073] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 01/18/2022] [Accepted: 01/25/2022] [Indexed: 11/23/2022] Open
Abstract
Selection of the appropriate DNA double-strand break (DSB) repair pathway is decisive for genetic stability. It is proposed to act according to two steps: 1-canonical nonhomologous end-joining (C-NHEJ) versus resection that generates single-stranded DNA (ssDNA) stretches; 2-on ssDNA, gene conversion (GC) versus nonconservative single-strand annealing (SSA) or alternative end-joining (A-EJ). Here, we addressed the mechanisms by which RAD51 regulates this second step, preventing nonconservative repair in human cells. Silencing RAD51 or BRCA2 stimulated both SSA and A-EJ, but not C-NHEJ, validating the two-step model. Three different RAD51 dominant-negative forms (DN-RAD51s) repressed GC and stimulated SSA/A-EJ. However, a fourth DN-RAD51 repressed SSA/A-EJ, although it efficiently represses GC. In living cells, the three DN-RAD51s that stimulate SSA/A-EJ failed to load efficiently onto damaged chromatin and inhibited the binding of endogenous RAD51, while the fourth DN-RAD51, which inhibits SSA/A-EJ, efficiently loads on damaged chromatin. Therefore, the binding of RAD51 to DNA, rather than its ability to promote GC, is required for SSA/A-EJ inhibition by RAD51. We showed that RAD51 did not limit resection of endonuclease-induced DSBs, but prevented spontaneous and RAD52-induced annealing of complementary ssDNA in vitro. Therefore, RAD51 controls the selection of the DSB repair pathway, protecting genome integrity from nonconservative DSB repair through ssDNA occupancy, independently of the promotion of CG.
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Affiliation(s)
- Ayeong So
- Université de Paris, INSERM U1016, UMR 8104 CNRS, Institut Cochin, Equipe Labellisée Ligue Contre le Cancer, France
- CNRS UMR 8200, Gustave-Roussy, Université Paris-Saclay, 114 rue Edouard Vaillant, 94805 Villejuif, France
| | - Elodie Dardillac
- Université de Paris, INSERM U1016, UMR 8104 CNRS, Institut Cochin, Equipe Labellisée Ligue Contre le Cancer, France
- CNRS UMR 8200, Gustave-Roussy, Université Paris-Saclay, 114 rue Edouard Vaillant, 94805 Villejuif, France
| | - Ali Muhammad
- Genome Maintenance and Molecular Microscopy UMR 9019 CNRS, Université Paris-Saclay, Gustave Roussy, F-94805, Villejuif Cedex, France
| | | | - Laura Sesma-Sanz
- Genome Stability Laboratory, CHU de Québec Research Center (Oncology Division), Quebec City, QC, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Laval University Cancer Research Center, Quebec City, QC, Canada
| | - Sandrine Ragu
- Université de Paris, INSERM U1016, UMR 8104 CNRS, Institut Cochin, Equipe Labellisée Ligue Contre le Cancer, France
- CNRS UMR 8200, Gustave-Roussy, Université Paris-Saclay, 114 rue Edouard Vaillant, 94805 Villejuif, France
| | - Eric Le Cam
- Genome Maintenance and Molecular Microscopy UMR 9019 CNRS, Université Paris-Saclay, Gustave Roussy, F-94805, Villejuif Cedex, France
| | - Yvan Canitrot
- CBI, CNRS UMR5088, LBCMCP, Toulouse University, Toulouse, France
| | - Jean Yves Masson
- Genome Stability Laboratory, CHU de Québec Research Center (Oncology Division), Quebec City, QC, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Laval University Cancer Research Center, Quebec City, QC, Canada
| | - Pauline Dupaigne
- Genome Maintenance and Molecular Microscopy UMR 9019 CNRS, Université Paris-Saclay, Gustave Roussy, F-94805, Villejuif Cedex, France
| | - Bernard S Lopez
- To whom correspondence should be addressed. Tel: +33 1 53 73 27 40;
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10
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Zhao X, Lu H, Usdin K. FAN1's protection against CGG repeat expansion requires its nuclease activity and is FANCD2-independent. Nucleic Acids Res 2021; 49:11643-11652. [PMID: 34718701 PMCID: PMC8599916 DOI: 10.1093/nar/gkab899] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 09/20/2021] [Accepted: 10/12/2021] [Indexed: 12/21/2022] Open
Abstract
The Repeat Expansion Diseases, a large group of human diseases that includes the fragile X-related disorders (FXDs) and Huntington's disease (HD), all result from expansion of a disease-specific microsatellite via a mechanism that is not fully understood. We have previously shown that mismatch repair (MMR) proteins are required for expansion in a mouse model of the FXDs, but that the FANCD2 and FANCI associated nuclease 1 (FAN1), a component of the Fanconi anemia (FA) DNA repair pathway, is protective. FAN1's nuclease activity has been reported to be dispensable for protection against expansion in an HD cell model. However, we show here that in a FXD mouse model a point mutation in the nuclease domain of FAN1 has the same effect on expansion as a null mutation. Furthermore, we show that FAN1 and another nuclease, EXO1, have an additive effect in protecting against MSH3-dependent expansions. Lastly, we show that the loss of FANCD2, a vital component of the Fanconi anemia DNA repair pathway, has no effect on expansions. Thus, FAN1 protects against MSH3-dependent expansions without diverting the expansion intermediates into the canonical FA pathway and this protection depends on FAN1 having an intact nuclease domain.
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Affiliation(s)
- Xiaonan Zhao
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Huiyan Lu
- Laboratory Animal Sciences section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Karen Usdin
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
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11
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Goold R, Hamilton J, Menneteau T, Flower M, Bunting EL, Aldous SG, Porro A, Vicente JR, Allen ND, Wilkinson H, Bates GP, Sartori AA, Thalassinos K, Balmus G, Tabrizi SJ. FAN1 controls mismatch repair complex assembly via MLH1 retention to stabilize CAG repeat expansion in Huntington's disease. Cell Rep 2021; 36:109649. [PMID: 34469738 PMCID: PMC8424649 DOI: 10.1016/j.celrep.2021.109649] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 06/30/2021] [Accepted: 08/11/2021] [Indexed: 11/18/2022] Open
Abstract
CAG repeat expansion in the HTT gene drives Huntington's disease (HD) pathogenesis and is modulated by DNA damage repair pathways. In this context, the interaction between FAN1, a DNA-structure-specific nuclease, and MLH1, member of the DNA mismatch repair pathway (MMR), is not defined. Here, we identify a highly conserved SPYF motif at the N terminus of FAN1 that binds to MLH1. Our data support a model where FAN1 has two distinct functions to stabilize CAG repeats. On one hand, it binds MLH1 to restrict its recruitment by MSH3, thus inhibiting the assembly of a functional MMR complex that would otherwise promote CAG repeat expansion. On the other hand, it promotes accurate repair via its nuclease activity. These data highlight a potential avenue for HD therapeutics in attenuating somatic expansion.
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Affiliation(s)
- Robert Goold
- UCL Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK; UK Dementia Research Institute, University College London, London WC1N 3BG, UK
| | - Joseph Hamilton
- UCL Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK; UK Dementia Research Institute, University College London, London WC1N 3BG, UK
| | - Thomas Menneteau
- UK Dementia Research Institute, University College London, London WC1N 3BG, UK; Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London WC1E 6BT, UK
| | - Michael Flower
- UCL Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK; UK Dementia Research Institute, University College London, London WC1N 3BG, UK
| | - Emma L Bunting
- UCL Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Sarah G Aldous
- UCL Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK; UK Dementia Research Institute, University College London, London WC1N 3BG, UK
| | - Antonio Porro
- Institute of Molecular Cancer Research, University of Zurich, Zurich 8057, Switzerland
| | - José R Vicente
- UK Dementia Research Institute, University of Cambridge, Cambridge CB2 0AH, UK
| | | | | | - Gillian P Bates
- UCL Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK; UK Dementia Research Institute, University College London, London WC1N 3BG, UK
| | - Alessandro A Sartori
- Institute of Molecular Cancer Research, University of Zurich, Zurich 8057, Switzerland
| | - Konstantinos Thalassinos
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London WC1E 6BT, UK; Institute of Structural and Molecular Biology, Birkbeck College, University of London, London WC1E 7HX, UK
| | - Gabriel Balmus
- UK Dementia Research Institute, University of Cambridge, Cambridge CB2 0AH, UK; Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0AH, UK.
| | - Sarah J Tabrizi
- UCL Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK; UK Dementia Research Institute, University College London, London WC1N 3BG, UK.
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12
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Raghunandan M, Yeo JE, Walter R, Saito K, Harvey AJ, Ittershagen S, Lee EA, Yang J, Hoatlin ME, Bielinsky AK, Hendrickson EA, Schärer O, Sobeck A. Functional cross talk between the Fanconi anemia and ATRX/DAXX histone chaperone pathways promotes replication fork recovery. Hum Mol Genet 2021; 29:1083-1095. [PMID: 31628488 DOI: 10.1093/hmg/ddz250] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 09/24/2019] [Accepted: 10/03/2019] [Indexed: 12/31/2022] Open
Abstract
Fanconi anemia (FA) is a chromosome instability syndrome characterized by increased cancer predisposition. Specifically, the FA pathway functions to protect genome stability during DNA replication. The central FA pathway protein, FANCD2, locates to stalled replication forks and recruits homologous recombination (HR) factors such as CtBP interacting protein (CtIP) to promote replication fork restart while suppressing new origin firing. Here, we identify alpha-thalassemia retardation syndrome X-linked (ATRX) as a novel physical and functional interaction partner of FANCD2. ATRX is a chromatin remodeler that forms a complex with Death domain-associated protein 6 (DAXX) to deposit the histone variant H3.3 into specific genomic regions. Intriguingly, ATRX was recently implicated in replication fork recovery; however, the underlying mechanism(s) remained incompletely understood. Our findings demonstrate that ATRX forms a constitutive protein complex with FANCD2 and protects FANCD2 from proteasomal degradation. ATRX and FANCD2 localize to stalled replication forks where they cooperate to recruit CtIP and promote MRE11 exonuclease-dependent fork restart while suppressing the firing of new replication origins. Remarkably, replication restart requires the concerted histone H3 chaperone activities of ATRX/DAXX and FANCD2, demonstrating that coordinated histone H3 variant deposition is a crucial event during the reinitiation of replicative DNA synthesis. Lastly, ATRX also cooperates with FANCD2 to promote the HR-dependent repair of directly induced DNA double-stranded breaks. We propose that ATRX is a novel functional partner of FANCD2 to promote histone deposition-dependent HR mechanisms in S-phase.
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Affiliation(s)
- Maya Raghunandan
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Jung Eun Yeo
- Center for Genomic Integrity (CGI), Institute for Basic Science (IBS), Ulsan, Republic of Korea
| | - Ryan Walter
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Kai Saito
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Adam J Harvey
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Stacie Ittershagen
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Eun-A Lee
- Center for Genomic Integrity (CGI), Institute for Basic Science (IBS), Ulsan, Republic of Korea
| | - Jihyeon Yang
- Center for Genomic Integrity (CGI), Institute for Basic Science (IBS), Ulsan, Republic of Korea
| | - Maureen E Hoatlin
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Anja K Bielinsky
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Eric A Hendrickson
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Orlando Schärer
- Center for Genomic Integrity (CGI), Institute for Basic Science (IBS), Ulsan, Republic of Korea.,School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Alexandra Sobeck
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA
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13
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Willaume S, Rass E, Fontanilla-Ramirez P, Moussa A, Wanschoor P, Bertrand P. A Link between Replicative Stress, Lamin Proteins, and Inflammation. Genes (Basel) 2021; 12:genes12040552. [PMID: 33918867 PMCID: PMC8070205 DOI: 10.3390/genes12040552] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/23/2021] [Accepted: 04/08/2021] [Indexed: 12/12/2022] Open
Abstract
Double-stranded breaks (DSB), the most toxic DNA lesions, are either a consequence of cellular metabolism, programmed as in during V(D)J recombination, or induced by anti-tumoral therapies or accidental genotoxic exposure. One origin of DSB sources is replicative stress, a major source of genome instability, especially when the integrity of the replication forks is not properly guaranteed. To complete stalled replication, restarting the fork requires complex molecular mechanisms, such as protection, remodeling, and processing. Recently, a link has been made between DNA damage accumulation and inflammation. Indeed, defects in DNA repair or in replication can lead to the release of DNA fragments in the cytosol. The recognition of this self-DNA by DNA sensors leads to the production of inflammatory factors. This beneficial response activating an innate immune response and destruction of cells bearing DNA damage may be considered as a novel part of DNA damage response. However, upon accumulation of DNA damage, a chronic inflammatory cellular microenvironment may lead to inflammatory pathologies, aging, and progression of tumor cells. Progress in understanding the molecular mechanisms of DNA damage repair, replication stress, and cytosolic DNA production would allow to propose new therapeutical strategies against cancer or inflammatory diseases associated with aging. In this review, we describe the mechanisms involved in DSB repair, the replicative stress management, and its consequences. We also focus on new emerging links between key components of the nuclear envelope, the lamins, and DNA repair, management of replicative stress, and inflammation.
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14
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Nolan M, Knudson K, Holz MK, Chaudhury I. Fanconi anemia and mTOR pathways functionally interact during stalled replication fork recovery. FEBS Lett 2021; 595:595-603. [PMID: 33423298 PMCID: PMC7993987 DOI: 10.1002/1873-3468.14035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/15/2020] [Accepted: 12/18/2020] [Indexed: 11/07/2022]
Abstract
We have previously demonstrated that Fanconi anemia (FA) proteins work in concert with other FA and non-FA proteins to mediate stalled replication fork restart. Previous studies suggest a connection between the FA protein FANCD2 and the non-FA protein mechanistic target of rapamycin (mTOR). A recent study showed that mTOR is involved in actin-dependent DNA replication fork restart, suggesting possible roles in the FA DNA repair pathway. In this study, we demonstrate that during replication stress mTOR interacts and cooperates with FANCD2 to provide cellular stability, mediate stalled replication fork restart, and prevent nucleolytic degradation of the nascent DNA strands. Taken together, this study unravels a novel functional cross-talk between two important mechanisms: mTOR and FA DNA repair pathways that ensure genomic stability.
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Affiliation(s)
| | | | | | - Indrajit Chaudhury
- University of Minnesota, Morris, MN
- presently at St. Mary’s College of Maryland, St.
Mary’s City, MD
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15
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Deshmukh AL, Porro A, Mohiuddin M, Lanni S, Panigrahi GB, Caron MC, Masson JY, Sartori AA, Pearson CE. FAN1, a DNA Repair Nuclease, as a Modifier of Repeat Expansion Disorders. J Huntingtons Dis 2021; 10:95-122. [PMID: 33579867 PMCID: PMC7990447 DOI: 10.3233/jhd-200448] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
FAN1 encodes a DNA repair nuclease. Genetic deficiencies, copy number variants, and single nucleotide variants of FAN1 have been linked to karyomegalic interstitial nephritis, 15q13.3 microdeletion/microduplication syndrome (autism, schizophrenia, and epilepsy), cancer, and most recently repeat expansion diseases. For seven CAG repeat expansion diseases (Huntington's disease (HD) and certain spinocerebellar ataxias), modification of age of onset is linked to variants of specific DNA repair proteins. FAN1 variants are the strongest modifiers. Non-coding disease-delaying FAN1 variants and coding disease-hastening variants (p.R507H and p.R377W) are known, where the former may lead to increased FAN1 levels and the latter have unknown effects upon FAN1 functions. Current thoughts are that ongoing repeat expansions in disease-vulnerable tissues, as individuals age, promote disease onset. Fan1 is required to suppress against high levels of ongoing somatic CAG and CGG repeat expansions in tissues of HD and FMR1 transgenic mice respectively, in addition to participating in DNA interstrand crosslink repair. FAN1 is also a modifier of autism, schizophrenia, and epilepsy. Coupled with the association of these diseases with repeat expansions, this suggests a common mechanism, by which FAN1 modifies repeat diseases. Yet how any of the FAN1 variants modify disease is unknown. Here, we review FAN1 variants, associated clinical effects, protein structure, and the enzyme's attributed functional roles. We highlight how variants may alter its activities in DNA damage response and/or repeat instability. A thorough awareness of the FAN1 gene and FAN1 protein functions will reveal if and how it may be targeted for clinical benefit.
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Affiliation(s)
- Amit L Deshmukh
- Program of Genetics & Genome Biology, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada
| | - Antonio Porro
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Mohiuddin Mohiuddin
- Program of Genetics & Genome Biology, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada
| | - Stella Lanni
- Program of Genetics & Genome Biology, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada
| | - Gagan B Panigrahi
- Program of Genetics & Genome Biology, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada
| | - Marie-Christine Caron
- Department of Molecular Biology, Medical Biochemistry and Pathology; Laval University Cancer Research Center, Québec City, Quebec, Canada.,Genome Stability Laboratory, CHU de Québec Research Center, HDQ Pavilion, Oncology Division, Québec City, Quebec, Canada
| | - Jean-Yves Masson
- Department of Molecular Biology, Medical Biochemistry and Pathology; Laval University Cancer Research Center, Québec City, Quebec, Canada.,Genome Stability Laboratory, CHU de Québec Research Center, HDQ Pavilion, Oncology Division, Québec City, Quebec, Canada
| | - Alessandro A Sartori
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Christopher E Pearson
- Program of Genetics & Genome Biology, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada.,University of Toronto, Program of Molecular Genetics, Toronto, Ontario, Canada
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16
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Zhou J, Zhou XA, Zhang N, Wang J. Evolving insights: how DNA repair pathways impact cancer evolution. Cancer Biol Med 2020; 17:805-827. [PMID: 33299637 PMCID: PMC7721097 DOI: 10.20892/j.issn.2095-3941.2020.0177] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 07/10/2020] [Indexed: 12/17/2022] Open
Abstract
Viewing cancer as a large, evolving population of heterogeneous cells is a common perspective. Because genomic instability is one of the fundamental features of cancer, this intrinsic tendency of genomic variation leads to striking intratumor heterogeneity and functions during the process of cancer formation, development, metastasis, and relapse. With the increased mutation rate and abundant diversity of the gene pool, this heterogeneity leads to cancer evolution, which is the major obstacle in the clinical treatment of cancer. Cells rely on the integrity of DNA repair machineries to maintain genomic stability, but these machineries often do not function properly in cancer cells. The deficiency of DNA repair could contribute to the generation of cancer genomic instability, and ultimately promote cancer evolution. With the rapid advance of new technologies, such as single-cell sequencing in recent years, we have the opportunity to better understand the specific processes and mechanisms of cancer evolution, and its relationship with DNA repair. Here, we review recent findings on how DNA repair affects cancer evolution, and discuss how these mechanisms provide the basis for critical clinical challenges and therapeutic applications.
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Affiliation(s)
- Jiadong Zhou
- Department of Radiation Medicine, Institute of Systems Biomedicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Xiao Albert Zhou
- Department of Radiation Medicine, Institute of Systems Biomedicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Ning Zhang
- Laboratory of Cancer Cell Biology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin's Clinical Research Center for Cancer, Tianjin 300060, China.,Biomedical Pioneering Innovation Center (BIOPIC) and Translational Cancer Research Center, School of Life Sciences, First Hospital, Peking University, Beijing 100871, China
| | - Jiadong Wang
- Department of Radiation Medicine, Institute of Systems Biomedicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
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17
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Abstract
Exposure to arsenic in contaminated drinking water is an emerging public health problem that impacts more than 200 million people worldwide. Accumulating lines of evidence from epidemiological studies revealed that chronic exposure to arsenic can result in various human diseases including cancer, type 2 diabetes, and neurodegenerative disorders. Arsenic is also classified as a Group I human carcinogen. In this review, we survey extensively different modes of action for arsenic-induced carcinogenesis, with focus being placed on arsenic-mediated impairment of DNA repair pathways. Inorganic arsenic can be bioactivated by methylation, and the ensuing products are highly genotoxic. Bioactivation of arsenicals also elicits the production of reactive oxygen and nitrogen species (ROS and RNS), which can directly damage DNA and modify cysteine residues in proteins. Results from recent studies suggest zinc finger proteins as crucial molecular targets for direct binding to As3+ or for modifications by arsenic-induced ROS/RNS, which may constitute a common mechanism underlying arsenic-induced perturbations of DNA repair.
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18
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Rikitake M, Fujikane R, Obayashi Y, Oka K, Ozaki M, Hidaka M. MLH1-mediated recruitment of FAN1 to chromatin for the induction of apoptosis triggered by O 6 -methylguanine. Genes Cells 2020; 25:175-186. [PMID: 31955481 DOI: 10.1111/gtc.12748] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 01/10/2020] [Accepted: 01/10/2020] [Indexed: 01/03/2023]
Abstract
O6 -Methylguanines (O6 -meG), which are produced in DNA by the action of alkylating agents, are mutagenic and cytotoxic, and induce apoptosis in a mismatch repair (MMR) protein-dependent manner. To understand the molecular mechanism of O6 -meG-induced apoptosis, we performed functional analyses of FANCD2 and FANCI-associated nuclease 1 (FAN1), which was identified as an interacting partner of MLH1. Immunoprecipitation analyses showed that FAN1 interacted with both MLH1 and MSH2 after treatment with N-methyl-N-nitrosourea (MNU), indicating the formation of a FAN1-MMR complex. In comparison with control cells, FAN1-knockdown cells were more resistant to MNU, and the appearances of a sub-G1 population and caspase-9 activation were suppressed. FAN1 formed nuclear foci in an MLH1-dependent manner after MNU treatment, and some were colocalized with both MLH1 foci and single-stranded DNA (ssDNA) created at damaged sites. Under the same condition, FANCD2 also formed nuclear foci, although it was dispensable for the formation of FAN1 foci and ssDNA. MNU-induced formation of ssDNA was dramatically suppressed in FAN1-knockdown cells. We therefore propose that FAN1 is loaded on chromatin through the interaction with MLH1 and produces ssDNA by its exonuclease activity, which contributes to the activation of the DNA damage response followed by the induction of apoptosis triggered by O6 -meG.
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Affiliation(s)
- Mihoko Rikitake
- Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka, Japan.,Department of Oral Growth and Development, Fukuoka Dental College, Fukuoka, Japan
| | - Ryosuke Fujikane
- Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka, Japan.,Oral Medicine Research Center, Fukuoka Dental College, Fukuoka, Japan
| | - Yuko Obayashi
- Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka, Japan.,Department of Oral and Maxillofacial Surgery, Fukuoka Dental College, Fukuoka, Japan
| | - Kyoko Oka
- Department of Oral Growth and Development, Fukuoka Dental College, Fukuoka, Japan
| | - Masao Ozaki
- Department of Oral Growth and Development, Fukuoka Dental College, Fukuoka, Japan
| | - Masumi Hidaka
- Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka, Japan.,Oral Medicine Research Center, Fukuoka Dental College, Fukuoka, Japan
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19
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Nolan M, Knudson K, Holz MK, Chaudhury I. Functional interaction between Fanconi anemia and mTOR pathways during stalled replication fork recovery.. [DOI: 10.1101/2020.01.16.899211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2023]
Abstract
ABSTRACTWe have previously demonstrated that Fanconi Anemia (FA) proteins work in concert with other FA and non-FA proteins to mediate stalled replication fork restart. Previous studies suggest a connection between FA protein FANCD2 and a non-FA protein mechanistic target of rapamycin (mTOR). A recent study showed that mTOR is involved in actin-dependent DNA replication fork restart, suggesting possible roles in FA DNA repair pathway. In this study, we demonstrate that during replication stress mTOR interacts and cooperates with FANCD2 to provide cellular stability, mediates stalled replication fork restart and prevents nucleolytic degradation of the nascent DNA strands. Taken together, this study unravels a novel functional cross-talk between two important mechanisms: mTOR and FA DNA repair pathways that ensure genomic stability.
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20
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Lopez-Martinez D, Kupculak M, Yang D, Yoshikawa Y, Liang CC, Wu R, Gygi SP, Cohn MA. Phosphorylation of FANCD2 Inhibits the FANCD2/FANCI Complex and Suppresses the Fanconi Anemia Pathway in the Absence of DNA Damage. Cell Rep 2019; 27:2990-3005.e5. [PMID: 31167143 PMCID: PMC6581795 DOI: 10.1016/j.celrep.2019.05.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 04/01/2019] [Accepted: 04/29/2019] [Indexed: 12/19/2022] Open
Abstract
Interstrand crosslinks (ICLs) of the DNA helix are a deleterious form of DNA damage. ICLs can be repaired by the Fanconi anemia pathway. At the center of the pathway is the FANCD2/FANCI complex, recruitment of which to DNA is a critical step for repair. After recruitment, monoubiquitination of both FANCD2 and FANCI leads to their retention on chromatin, ensuring subsequent repair. However, regulation of recruitment is poorly understood. Here, we report a cluster of phosphosites on FANCD2 whose phosphorylation by CK2 inhibits both FANCD2 recruitment to ICLs and its monoubiquitination in vitro and in vivo. We have found that phosphorylated FANCD2 possesses reduced DNA binding activity, explaining the previous observations. Thus, we describe a regulatory mechanism operating as a molecular switch, where in the absence of DNA damage, the FANCD2/FANCI complex is prevented from loading onto DNA, effectively suppressing the FA pathway.
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Affiliation(s)
| | - Marian Kupculak
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | - Di Yang
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | | | - Chih-Chao Liang
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | - Ronghu Wu
- Department of Cell Biology, Harvard Medical School, Boston, MA 01125, USA
| | - Steven P Gygi
- Department of Cell Biology, Harvard Medical School, Boston, MA 01125, USA
| | - Martin A Cohn
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK.
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21
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Ge C, Vilfranc CL, Che L, Pandita RK, Hambarde S, Andreassen PR, Niu L, Olowokure O, Shah S, Waltz SE, Zou L, Wang J, Pandita TK, Du C. The BRUCE-ATR Signaling Axis Is Required for Accurate DNA Replication and Suppression of Liver Cancer Development. Hepatology 2019; 69:2608-2622. [PMID: 30693543 PMCID: PMC6541504 DOI: 10.1002/hep.30529] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 01/23/2019] [Indexed: 01/10/2023]
Abstract
Replication fork stability during DNA replication is vital for maintenance of genomic stability and suppression of cancer development in mammals. ATR (ataxia-telangiectasia mutated [ATM] and RAD3-related) is a master regulatory kinase that activates the replication stress response to overcome replication barriers. Although many downstream effectors of ATR have been established, the upstream regulators of ATR and the effect of such regulation on liver cancer remain unclear. The ubiquitin conjugase BRUCE (BIR Repeat containing Ubiquitin-Conjugating Enzyme) is a guardian of chromosome integrity and activator of ATM signaling, which promotes DNA double-strand break repair through homologous recombination. Here we demonstrate the functions for BRUCE in ATR activation in vitro and liver tumor suppression in vivo. BRUCE is recruited to induced DNA damage sites. Depletion of BRUCE inhibited multiple ATR-dependent signaling events during replication stress, including activation of ATR itself, phosphorylation of its downstream targets CHK1 and RPA, and the mono-ubiquitination of FANCD2. Consequently, BRUCE deficiency resulted in stalled DNA replication forks and increased firing of new replication origins. The in vivo impact of BRUCE loss on liver tumorigenesis was determined using the hepatocellular carcinoma model induced by genotoxin diethylnitrosamine. Liver-specific knockout of murine Bruce impaired ATR activation and exacerbated inflammation, fibrosis and hepatocellular carcinoma, which exhibited a trabecular architecture, closely resembling human hepatocellular carcinoma (HCC). In humans, the clinical relevance of BRUCE down-regulation in liver disease was found in hepatitis, cirrhosis, and HCC specimens, and deleterious somatic mutations of the Bruce gene was found in human hepatocellular carcinoma in the Cancer Genome Atlas database. Conclusion: These findings establish a BRUCE-ATR signaling axis in accurate DNA replication and suppression of liver cancer in mice and humans and provides a clinically relevant HCC mouse model.
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Affiliation(s)
- Chunmin Ge
- Department of Cancer and Cell Biology, University of Cincinnati, Cincinnati, Ohio 45267
| | | | - Lixiao Che
- Department of Cancer and Cell Biology, University of Cincinnati, Cincinnati, Ohio 45267
| | - Raj K. Pandita
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston Texas 77030
| | - Shashank Hambarde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston Texas 77030
| | - Paul R. Andreassen
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children Hospital Medical Center, Cincinnati, Ohio 45229
| | - Liang Niu
- Department of Environmental Health, University of Cincinnati, Cincinnati, Ohio 45267
| | - Olugbenga Olowokure
- Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio 45267
| | - Shimul Shah
- University of Cincinnati College of Medicine, University of Cincinnati, Cincinnati, Ohio 45267
| | - Susan E. Waltz
- Department of Cancer and Cell Biology, University of Cincinnati, Cincinnati, Ohio 45267
| | - Lee Zou
- Department of Pathology, Massachusetts General Hospital Cancer Center; Harvard Medical School, Charlestown, MA 02129
| | - Jiang Wang
- Department of Pathology, University of Cincinnati, Cincinnati, Ohio 45267
| | - Tej K. Pandita
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston Texas 77030
| | - Chunying Du
- Department of Cancer and Cell Biology, University of Cincinnati, Cincinnati, Ohio 45267,Corresponding author: Chunying Du, Ph.D. Phone: (513) 558-4803,
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22
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Dattani A, Wilkinson SR. Deciphering the interstrand crosslink DNA repair network expressed by Trypanosoma brucei. DNA Repair (Amst) 2019; 78:154-166. [DOI: 10.1016/j.dnarep.2019.04.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 03/29/2019] [Accepted: 04/24/2019] [Indexed: 10/26/2022]
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23
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Datta A, Brosh RM. Holding All the Cards-How Fanconi Anemia Proteins Deal with Replication Stress and Preserve Genomic Stability. Genes (Basel) 2019; 10:genes10020170. [PMID: 30813363 PMCID: PMC6409899 DOI: 10.3390/genes10020170] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 02/14/2019] [Accepted: 02/15/2019] [Indexed: 12/18/2022] Open
Abstract
Fanconi anemia (FA) is a hereditary chromosomal instability disorder often displaying congenital abnormalities and characterized by a predisposition to progressive bone marrow failure (BMF) and cancer. Over the last 25 years since the discovery of the first linkage of genetic mutations to FA, its molecular genetic landscape has expanded tremendously as it became apparent that FA is a disease characterized by a defect in a specific DNA repair pathway responsible for the correction of covalent cross-links between the two complementary strands of the DNA double helix. This pathway has become increasingly complex, with the discovery of now over 20 FA-linked genes implicated in interstrand cross-link (ICL) repair. Moreover, gene products known to be involved in double-strand break (DSB) repair, mismatch repair (MMR), and nucleotide excision repair (NER) play roles in the ICL response and repair of associated DNA damage. While ICL repair is predominantly coupled with DNA replication, it also can occur in non-replicating cells. DNA damage accumulation and hematopoietic stem cell failure are thought to contribute to the increased inflammation and oxidative stress prevalent in FA. Adding to its confounding nature, certain FA gene products are also engaged in the response to replication stress, caused endogenously or by agents other than ICL-inducing drugs. In this review, we discuss the mechanistic aspects of the FA pathway and the molecular defects leading to elevated replication stress believed to underlie the cellular phenotypes and clinical features of FA.
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Affiliation(s)
- Arindam Datta
- Laboratory of Molecular Gerontology, National Institute on Aging, NIH, NIH Biomedical Research Center, Baltimore, MD 21224, USA.
| | - Robert M Brosh
- Laboratory of Molecular Gerontology, National Institute on Aging, NIH, NIH Biomedical Research Center, Baltimore, MD 21224, USA.
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24
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Goold R, Flower M, Moss DH, Medway C, Wood-Kaczmar A, Andre R, Farshim P, Bates GP, Holmans P, Jones L, Tabrizi SJ. FAN1 modifies Huntington's disease progression by stabilizing the expanded HTT CAG repeat. Hum Mol Genet 2019; 28:650-661. [PMID: 30358836 PMCID: PMC6360275 DOI: 10.1093/hmg/ddy375] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/15/2018] [Accepted: 10/16/2018] [Indexed: 11/13/2022] Open
Abstract
Huntington's disease (HD) is an inherited neurodegenerative disease caused by an expanded CAG repeat in the huntingtin (HTT) gene. CAG repeat length explains around half of the variation in age at onset (AAO) but genetic variation elsewhere in the genome accounts for a significant proportion of the remainder. Genome-wide association studies have identified a bidirectional signal on chromosome 15, likely underlain by FANCD2- and FANCI-associated nuclease 1 (FAN1), a nuclease involved in DNA interstrand cross link repair. Here we show that increased FAN1 expression is significantly associated with delayed AAO and slower progression of HD, suggesting FAN1 is protective in the context of an expanded HTT CAG repeat. FAN1 overexpression in human cells reduces CAG repeat expansion in exogenously expressed mutant HTT exon 1, and in patient-derived stem cells and differentiated medium spiny neurons, FAN1 knockdown increases CAG repeat expansion. The stabilizing effects are FAN1 concentration and CAG repeat length-dependent. We show that FAN1 binds to the expanded HTT CAG repeat DNA and its nuclease activity is not required for protection against CAG repeat expansion. These data shed new mechanistic insights into how the genetic modifiers of HD act to alter disease progression and show that FAN1 affects somatic expansion of the CAG repeat through a nuclease-independent mechanism. This provides new avenues for therapeutic interventions in HD and potentially other triplet repeat disorders.
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Affiliation(s)
- Robert Goold
- UCL Huntington’s Disease Centre,Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London,Queen Square, London WC1N 3BG, UK
| | - Michael Flower
- UCL Huntington’s Disease Centre,Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London,Queen Square, London WC1N 3BG, UK
| | - Davina Hensman Moss
- UCL Huntington’s Disease Centre,Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London,Queen Square, London WC1N 3BG, UK
| | - Chris Medway
- Medical Research Council Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, CF24 4HQ, UK
| | - Alison Wood-Kaczmar
- UCL Huntington’s Disease Centre,Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London,Queen Square, London WC1N 3BG, UK
| | - Ralph Andre
- UCL Huntington’s Disease Centre,Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London,Queen Square, London WC1N 3BG, UK
| | - Pamela Farshim
- UCL Huntington’s Disease Centre,Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London,Queen Square, London WC1N 3BG, UK
| | - Gill P Bates
- UCL Huntington’s Disease Centre,Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London,Queen Square, London WC1N 3BG, UK
- UK Dementia Research Institute, University College London, WC1N 3BG, UK
| | - Peter Holmans
- Medical Research Council Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, CF24 4HQ, UK
| | - Lesley Jones
- Medical Research Council Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, CF24 4HQ, UK
| | - Sarah J Tabrizi
- UCL Huntington’s Disease Centre,Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London,Queen Square, London WC1N 3BG, UK
- UK Dementia Research Institute, University College London, WC1N 3BG, UK
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Kim SM, Forsburg SL. Regulation of Structure-Specific Endonucleases in Replication Stress. Genes (Basel) 2018; 9:genes9120634. [PMID: 30558228 PMCID: PMC6316474 DOI: 10.3390/genes9120634] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 12/11/2018] [Accepted: 12/12/2018] [Indexed: 12/16/2022] Open
Abstract
Replication stress results in various forms of aberrant replication intermediates that need to be resolved for faithful chromosome segregation. Structure-specific endonucleases (SSEs) recognize DNA secondary structures rather than primary sequences and play key roles during DNA repair and replication stress. Holliday junction resolvase MUS81 (methyl methane sulfonate (MMS), and UV-sensitive protein 81) and XPF (xeroderma pigmentosum group F-complementing protein) are a subset of SSEs that resolve aberrant replication structures. To ensure genome stability and prevent unnecessary DNA breakage, these SSEs are tightly regulated by the cell cycle and replication checkpoints. We discuss the regulatory network that control activities of MUS81 and XPF and briefly mention other SSEs involved in the resolution of replication intermediates.
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Affiliation(s)
- Seong Min Kim
- Program in Molecular & Computational Biology, University of Southern California, Los Angeles, CA 90089, USA.
| | - Susan L Forsburg
- Program in Molecular & Computational Biology, University of Southern California, Los Angeles, CA 90089, USA.
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26
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Yates M, Maréchal A. Ubiquitylation at the Fork: Making and Breaking Chains to Complete DNA Replication. Int J Mol Sci 2018; 19:E2909. [PMID: 30257459 PMCID: PMC6213728 DOI: 10.3390/ijms19102909] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 09/20/2018] [Accepted: 09/24/2018] [Indexed: 12/11/2022] Open
Abstract
The complete and accurate replication of the genome is a crucial aspect of cell proliferation that is often perturbed during oncogenesis. Replication stress arising from a variety of obstacles to replication fork progression and processivity is an important contributor to genome destabilization. Accordingly, cells mount a complex response to this stress that allows the stabilization and restart of stalled replication forks and enables the full duplication of the genetic material. This response articulates itself on three important platforms, Replication Protein A/RPA-coated single-stranded DNA, the DNA polymerase processivity clamp PCNA and the FANCD2/I Fanconi Anemia complex. On these platforms, the recruitment, activation and release of a variety of genome maintenance factors is regulated by post-translational modifications including mono- and poly-ubiquitylation. Here, we review recent insights into the control of replication fork stability and restart by the ubiquitin system during replication stress with a particular focus on human cells. We highlight the roles of E3 ubiquitin ligases, ubiquitin readers and deubiquitylases that provide the required flexibility at stalled forks to select the optimal restart pathways and rescue genome stability during stressful conditions.
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Affiliation(s)
- Maïlyn Yates
- Department of Biology, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada.
| | - Alexandre Maréchal
- Department of Biology, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada.
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27
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Bonetti D, Colombo CV, Clerici M, Longhese MP. Processing of DNA Ends in the Maintenance of Genome Stability. Front Genet 2018; 9:390. [PMID: 30258457 PMCID: PMC6143663 DOI: 10.3389/fgene.2018.00390] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 08/29/2018] [Indexed: 12/17/2022] Open
Abstract
DNA double-strand breaks (DSBs) are particularly hazardous lesions as their inappropriate repair can result in chromosome rearrangements, an important driving force of tumorigenesis. DSBs can be repaired by end joining mechanisms or by homologous recombination (HR). HR requires the action of several nucleases that preferentially remove the 5′-terminated strands at both DSB ends in a process called DNA end resection. The same nucleases are also involved in the processing of replication fork structures. Much of our understanding of these pathways has come from studies in the model organism Saccharomyces cerevisiae. Here, we review the current knowledge of the mechanism of resection at DNA DSBs and replication forks.
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Affiliation(s)
- Diego Bonetti
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
| | | | - Michela Clerici
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
| | - Maria Pia Longhese
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
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28
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Pasero P, Vindigni A. Nucleases Acting at Stalled Forks: How to Reboot the Replication Program with a Few Shortcuts. Annu Rev Genet 2018; 51:477-499. [PMID: 29178820 DOI: 10.1146/annurev-genet-120116-024745] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In a lifetime, a human being synthesizes approximately 2×1016 meters of DNA, a distance that corresponds to 130,000 times the distance between the Earth and the Sun. This daunting task is executed by thousands of replication forks, which progress along the chromosomes and frequently stall when they encounter DNA lesions, unusual DNA structures, RNA polymerases, or tightly-bound protein complexes. To complete DNA synthesis before the onset of mitosis, eukaryotic cells have evolved complex mechanisms to process and restart arrested forks through the coordinated action of multiple nucleases, topoisomerases, and helicases. In this review, we discuss recent advances in understanding the role and regulation of nucleases acting at stalled forks with a focus on the nucleolytic degradation of nascent DNA, a process commonly referred to as fork resection. We also discuss the effects of deregulated fork resection on genomic instability and on the unscheduled activation of the interferon response under replication stress conditions.
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Affiliation(s)
- Philippe Pasero
- Institute of Human Genetics, CNRS UMR9002, University of Montpellier, 34396 Montpellier, France;
| | - Alessandro Vindigni
- Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri 63104, USA;
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29
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Jin H, Roy U, Lee G, Schärer OD, Cho Y. Structural mechanism of DNA interstrand cross-link unhooking by the bacterial FAN1 nuclease. J Biol Chem 2018; 293:6482-6496. [PMID: 29514982 PMCID: PMC5925792 DOI: 10.1074/jbc.ra118.002171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/05/2018] [Indexed: 01/04/2023] Open
Abstract
DNA interstrand cross-links (ICLs) block the progress of the replication and transcription machineries and can weaken chromosomal stability, resulting in various diseases. FANCD2-FANCI-associated nuclease (FAN1) is a conserved structure-specific nuclease that unhooks DNA ICLs independently of the Fanconi anemia pathway. Recent structural studies have proposed two different mechanistic features for ICL unhooking by human FAN1: a specific basic pocket that recognizes the terminal phosphate of a 1-nucleotide (nt) 5' flap or FAN1 dimerization. Herein, we show that despite lacking these features, Pseudomonas aeruginosa FAN1 (PaFAN1) cleaves substrates at ∼3-nt intervals and resolves ICLs. Crystal structures of PaFAN1 bound to various DNA substrates revealed that its conserved basic Arg/Lys patch comprising Arg-228 and Lys-260 recognizes phosphate groups near the 5' terminus of a DNA substrate with a 1-nt flap or a nick. Substitution of Lys-260 did not affect PaFAN1's initial endonuclease activity but significantly decreased its subsequent exonuclease activity and ICL unhooking. The Arg/Lys patch also interacted with phosphates at a 3-nt gap, and this interaction could drive movement of the scissile phosphates into the PaFAN1-active site. In human FAN1, the ICL-resolving activity was not affected by individual disruption of the Arg/Lys patch or basic pocket. However, simultaneous substitution of both FAN1 regions significantly reduced its ICL-resolving activity, suggesting that these two basic regions play a complementary role in ICL repair. On the basis of these findings, we propose a conserved role for two basic regions in FAN1 to guide ICL unhooking and to maintain genomic stability.
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Affiliation(s)
- Hyeonseok Jin
- From the Department of Life Science, Pohang University of Science and Technology, Pohang, Kyungbook 37673, South Korea
| | - Upasana Roy
- the Departments of Chemistry and Pharmacological Sciences, Stony Brook University, Stony Brook, New York 11794
| | - Gwangrog Lee
- the Department of Biology, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea
| | - Orlando D Schärer
- the Departments of Chemistry and Pharmacological Sciences, Stony Brook University, Stony Brook, New York 11794
- the Center for Genomic Integrity, Institute for Basic Science, Ulsan 44919, South Korea, and
- the Department of Biological Sciences, School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, South Korea
| | - Yunje Cho
- From the Department of Life Science, Pohang University of Science and Technology, Pohang, Kyungbook 37673, South Korea,
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30
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Federico MB, Campodónico P, Paviolo NS, Gottifredi V. Beyond interstrand crosslinks repair: contribution of FANCD2 and other Fanconi Anemia proteins to the replication of DNA. Mutat Res 2018; 808:83-92. [PMID: 29031493 DOI: 10.1016/j.mrfmmm.2017.09.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/11/2017] [Indexed: 06/07/2023]
Abstract
Biallelic mutations of FANCD2 and other components of the Fanconi Anemia (FA) pathway cause a disease characterized by bone marrow failure, cancer predisposition and a striking sensitivity to agents that induce crosslinks between the two complementary DNA strands (inter-strand crosslinks-ICL). Such genotoxins were used to characterize the contribution of the FA pathway to the genomic stability of cells, thus unravelling the biological relevance of ICL repair in the context of the disease. Notwithstanding this, whether the defect in ICL repair as the sole trigger for the multiple physiological alterations observed in FA patients is still under investigation. Remarkably, ICL-independent functions of FANCD2 and other components of the FA pathway were recently reported. FANCD2 contributes to the processing of very challenging double strand ends (DSEs: one ended Double Strand Breaks -DSBs- created during DNA replication). Other ICL-independent functions of FANCD2 include prevention of DNA breakage at stalled replication forks and facilitation of chromosome segregation at the end of M phase. The current understanding of replication-associated functions of FANCD2 and its relevance for the survival of genomically stable cells is herein discussed.
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Affiliation(s)
- Maria B Federico
- Cell Cycle and Genomic Stability Laboratory, Fundación Instituto Leloir-Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina
| | - Paola Campodónico
- Cell Cycle and Genomic Stability Laboratory, Fundación Instituto Leloir-Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina
| | - Natalia S Paviolo
- Cell Cycle and Genomic Stability Laboratory, Fundación Instituto Leloir-Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina
| | - Vanesa Gottifredi
- Cell Cycle and Genomic Stability Laboratory, Fundación Instituto Leloir-Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina.
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31
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Thompson EL, Yeo JE, Lee EA, Kan Y, Raghunandan M, Wiek C, Hanenberg H, Schärer OD, Hendrickson EA, Sobeck A. FANCI and FANCD2 have common as well as independent functions during the cellular replication stress response. Nucleic Acids Res 2017; 45:11837-11857. [PMID: 29059323 PMCID: PMC5714191 DOI: 10.1093/nar/gkx847] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 09/16/2017] [Indexed: 11/18/2022] Open
Abstract
Fanconi anemia (FA) is an inherited cancer predisposition syndrome characterized by cellular hypersensitivity to DNA interstrand crosslinks (ICLs). To repair these lesions, the FA proteins act in a linear hierarchy: following ICL detection on chromatin, the FA core complex monoubiquitinates and recruits the central FANCI and FANCD2 proteins that subsequently coordinate ICL removal and repair of the ensuing DNA double-stranded break by homology-dependent repair (HDR). FANCD2 also functions during the replication stress response by mediating the restart of temporarily stalled replication forks thereby suppressing the firing of new replication origins. To address if FANCI is also involved in these FANCD2-dependent mechanisms, we generated isogenic FANCI-, FANCD2- and FANCI:FANCD2 double-null cells. We show that FANCI and FANCD2 are partially independent regarding their protein stability, nuclear localization and chromatin recruitment and contribute independently to cellular proliferation. Simultaneously, FANCD2—but not FANCI—plays a major role in HDR-mediated replication restart and in suppressing new origin firing. Consistent with this observation, deficiencies in HDR-mediated DNA DSB repair can be overcome by stabilizing RAD51 filament formation in cells lacking functional FANCD2. We propose that FANCI and FANCD2 have partially non-overlapping and possibly even opposing roles during the replication stress response.
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Affiliation(s)
- Elizabeth L Thompson
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jung E Yeo
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.,Center for Genomic Integrity (CGI), Institute for Basic Science (IBS), Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, South Korea
| | - Eun-A Lee
- Center for Genomic Integrity (CGI), Institute for Basic Science (IBS), Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, South Korea
| | - Yinan Kan
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Maya Raghunandan
- Center for Genomic Integrity (CGI), Institute for Basic Science (IBS), Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, South Korea
| | - Constanze Wiek
- Department of Otorhinolaryngology and Head/Neck Surgery, Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Helmut Hanenberg
- Department of Otorhinolaryngology and Head/Neck Surgery, Heinrich-Heine University, 40225 Düsseldorf, Germany.,Department of Pediatrics III, University Children's Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany
| | - Orlando D Schärer
- Center for Genomic Integrity (CGI), Institute for Basic Science (IBS), Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, South Korea
| | - Eric A Hendrickson
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Alexandra Sobeck
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
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Sidorova J. A game of substrates: replication fork remodeling and its roles in genome stability and chemo-resistance. Cell Stress 2017; 1:115-133. [PMID: 29355244 PMCID: PMC5771654 DOI: 10.15698/cst2017.12.114] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 11/27/2017] [Accepted: 11/29/2017] [Indexed: 01/06/2023] Open
Abstract
During the hours that human cells spend in the DNA synthesis (S) phase of the cell cycle, they may encounter adversities such as DNA damage or shortage of nucleotides. Under these stresses, replication forks in DNA may experience slowing, stalling, and breakage. Fork remodeling mechanisms, which stabilize slow or stalled replication forks and ensure their ability to continue or resume replication, protect cells from genomic instability and carcinogenesis. Fork remodeling includes DNA strand exchanges that result in annealing of newly synthesized strands (fork reversal), controlled DNA resection, and cleavage of DNA strands. Defects in major tumor suppressor genes BRCA1 and BRCA2, and a subset of the Fanconi Anemia genes have been shown to result in deregulation in fork remodeling, and most prominently, loss of kilobases of nascent DNA from stalled replication forks. This phenomenon has recently gained spotlight as a potential marker and mediator of chemo-sensitivity in cancer cells and, conversely, its suppression - as a hallmark of acquired chemo-resistance. Moreover, nascent strand degradation at forks is now known to also trigger innate immune response to self-DNA. An increasingly sophisticated molecular description of these events now points at a combination of unbalanced fork reversal and end-resection as a root cause, yet also reveals the multi-layered complexity and heterogeneity of the underlying processes in normal and cancer cells.
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Affiliation(s)
- Julia Sidorova
- Department of Pathology, University of Washington, Seattle, Washington, USA
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33
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FAN1 interaction with ubiquitylated PCNA alleviates replication stress and preserves genomic integrity independently of BRCA2. Nat Commun 2017; 8:1073. [PMID: 29051491 PMCID: PMC5648898 DOI: 10.1038/s41467-017-01074-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Accepted: 08/16/2017] [Indexed: 11/08/2022] Open
Abstract
Interstrand cross-link (ICL) hypersensitivity is a characteristic trait of Fanconi anemia (FA). Although FANCD2-associated nuclease 1 (FAN1) contributes to ICL repair, FAN1 mutations predispose to karyomegalic interstitial nephritis (KIN) and cancer rather than to FA. Thus, the biological role of FAN1 remains unclear. Because fork stalling in FAN1-deficient cells causes chromosomal instability, we reasoned that the key function of FAN1 might lie in the processing of halted replication forks. Here, we show that FAN1 contains a previously-uncharacterized PCNA interacting peptide (PIP) motif that, together with its ubiquitin-binding zinc finger (UBZ) domain, helps recruit FAN1 to ubiquitylated PCNA accumulated at stalled forks. This prevents replication fork collapse and controls their progression. Furthermore, we show that FAN1 preserves replication fork integrity by a mechanism that is distinct from BRCA2-dependent homologous recombination. Thus, targeting FAN1 activities and its interaction with ubiquitylated PCNA may offer therapeutic opportunities for treatment of BRCA-deficient tumors.
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Federico MB, Campodónico P, Paviolo NS, Gottifredi V. ACCIDENTAL DUPLICATION: Beyond interstrand crosslinks repair: Contribution of FANCD2 and other Fanconi Anemia proteins to the replication of DNA. Mutat Res 2017:S0027-5107(17)30167-7. [PMID: 28966006 DOI: 10.1016/j.mrfmmm.2017.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 09/24/2017] [Indexed: 11/30/2022]
Abstract
The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/ 10.1016/j.mrfmmm.2017.09.006. This duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.
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Affiliation(s)
- Maria B Federico
- Cell Cycle and Genomic Stability Laboratory, Fundación Instituto Leloir-Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina
| | - Paola Campodónico
- Cell Cycle and Genomic Stability Laboratory, Fundación Instituto Leloir-Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina
| | - Natalia S Paviolo
- Cell Cycle and Genomic Stability Laboratory, Fundación Instituto Leloir-Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina
| | - Vanesa Gottifredi
- Cell Cycle and Genomic Stability Laboratory, Fundación Instituto Leloir-Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina.
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36
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Jiang J, Bellani M, Li L, Wang P, Seidman MM, Wang Y. Arsenite Binds to the RING Finger Domain of FANCL E3 Ubiquitin Ligase and Inhibits DNA Interstrand Crosslink Repair. ACS Chem Biol 2017; 12:1858-1866. [PMID: 28535027 DOI: 10.1021/acschembio.6b01135] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Human exposure to arsenic in drinking water is known to be associated with the development of bladder, lung, kidney, and skin cancers. The molecular mechanisms underlying the carcinogenic effects of arsenic species remain incompletely understood. DNA interstrand cross-links (ICLs) are among the most cytotoxic type of DNA lesions that block DNA replication and transcription, and these lesions can be induced by endogenous metabolism and by exposure to exogenous agents. Fanconi anemia (FA) is a congenital disorder manifested with elevated sensitivity toward DNA interstrand cross-linking agents, and monoubiquitination of FANCD2 by FANCL is a crucial step in FA-mediated DNA repair. Here, we demonstrated that As3+ could bind to the PHD/RING finger domain of FANCL in vitro and in cells. This binding led to compromised ubiquitination of FANCD2 in cells and diminished recruitment of FANCD2 to chromatin and DNA damage sites induced by 4,5',8-trimethylpsoralen plus UVA irradiation. Furthermore, clonogenic survival assay results showed that arsenite coexposure rendered cells more sensitive toward DNA interstrand cross-linking agents. Together, our study suggested that arsenite may compromise genomic stability via perturbation of the Fanconi anemia pathway, thereby conferring its carcinogenic effect.
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Affiliation(s)
| | - Marina Bellani
- Laboratory
of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
| | | | | | - Michael M. Seidman
- Laboratory
of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
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Ishiai M, Sato K, Tomida J, Kitao H, Kurumizaka H, Takata M. Activation of the FA pathway mediated by phosphorylation and ubiquitination. Mutat Res 2017; 803-805:89-95. [PMID: 28552166 DOI: 10.1016/j.mrfmmm.2017.05.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 05/04/2017] [Accepted: 05/04/2017] [Indexed: 12/15/2022]
Abstract
Fanconi anemia (FA) is a devastating hereditary condition that impacts genome integrity, leading to clinical features such as skeletal and visceral organ malformations, attrition of bone marrow stem cells, and carcinogenesis. At least 21 proteins, when absent or defective, have been implicated in this disorder, and they together constitute the FA pathway, which functions in detection and repair of, and tolerance to, endogenous DNA damage. The damage primarily handled by the FA pathway has been assumed to be related to DNA interstrand crosslinks (ICLs). The FA pathway is activated upon ICL damage, and a hallmark of this activation is the mono-ubiquitination events of the key FANCD2-FANCI protein complex. Recent data have revealed unexpectedly complex details in the regulation of FA pathway activation by ICLs. In this short review, we summarize the knowledge accumulated over the years regarding how the FA pathway is activated via protein modifications.
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Affiliation(s)
- Masamichi Ishiai
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Kyoto University, Kyoto, Japan
| | - Koichi Sato
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Junya Tomida
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Kyoto University, Kyoto, Japan
| | - Hiroyuki Kitao
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Kyoto University, Kyoto, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan.
| | - Minoru Takata
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Kyoto University, Kyoto, Japan.
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Branzei D, Szakal B. Building up and breaking down: mechanisms controlling recombination during replication. Crit Rev Biochem Mol Biol 2017; 52:381-394. [PMID: 28325102 DOI: 10.1080/10409238.2017.1304355] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The complete and faithful duplication of the genome is an essential prerequisite for proliferating cells to maintain genome integrity. This objective is greatly challenged by DNA damage encountered during replication, which causes fork stalling and in certain cases, fork breakage. DNA damage tolerance (DDT) pathways mitigate the effects on fork stability induced by replication fork stalling by mediating damage-bypass and replication fork restart. These DDT mechanisms, largely relying on homologous recombination (HR) and specialized polymerases, can however contribute to genome rearrangements and mutagenesis. There is a profound connection between replication and recombination: recombination proteins protect replication forks from nuclease-mediated degradation of the nascent DNA strands and facilitate replication completion in cells challenged by DNA damage. Moreover, in case of fork collapse and formation of double strand breaks (DSBs), the recombination factors present or recruited to the fork facilitate HR-mediated DSB repair, which is primarily error-free. Disruption of HR is inexorably linked to genome instability, but the premature activation of HR during replication often leads to genome rearrangements. Faithful replication necessitates the downregulation of HR and disruption of active RAD51 filaments at replication forks, but upon persistent fork stalling, building up of HR is critical for the reorganization of the replication fork and for filling-in of the gaps associated with discontinuous replication induced by DNA lesions. Here we summarize and reflect on our understanding of the mechanisms that either suppress recombination or locally enhance it during replication, and the principles that underlie this regulation.
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Affiliation(s)
- Dana Branzei
- a IFOM, the FIRC Institute of Molecular Oncology , Milan , Italy
| | - Barnabas Szakal
- a IFOM, the FIRC Institute of Molecular Oncology , Milan , Italy
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Dehé PM, Gaillard PHL. Control of structure-specific endonucleases to maintain genome stability. Nat Rev Mol Cell Biol 2017; 18:315-330. [PMID: 28327556 DOI: 10.1038/nrm.2016.177] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Structure-specific endonucleases (SSEs) have key roles in DNA replication, recombination and repair, and emerging roles in transcription. These enzymes have specificity for DNA secondary structure rather than for sequence, and therefore their activity must be precisely controlled to ensure genome stability. In this Review, we discuss how SSEs are controlled as part of genome maintenance pathways in eukaryotes, with an emphasis on the elaborate mechanisms that regulate the members of the major SSE families - including the xeroderma pigmentosum group F-complementing protein (XPF) and MMS and UV-sensitive protein 81 (MUS81)-dependent nucleases, and the flap endonuclease 1 (FEN1), XPG and XPG-like endonuclease 1 (GEN1) enzymes - during processes such as DNA adduct repair, Holliday junction processing and replication stress. We also discuss newly characterized connections between SSEs and other classes of DNA-remodelling enzymes and cell cycle control machineries, which reveal the importance of SSE scaffolds such as the synthetic lethal of unknown function 4 (SLX4) tumour suppressor for the maintenance of genome stability.
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Affiliation(s)
- Pierre-Marie Dehé
- Centre de Recherche en Cancérologie de Marseille, CRCM, CNRS, Aix Marseille Université, INSERM, Institut Paoli-Calmettes, 27 Boulevard Leï Roure, 13009 Marseille, France
| | - Pierre-Henri L Gaillard
- Centre de Recherche en Cancérologie de Marseille, CRCM, CNRS, Aix Marseille Université, INSERM, Institut Paoli-Calmettes, 27 Boulevard Leï Roure, 13009 Marseille, France
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Common Chemical Inductors of Replication Stress: Focus on Cell-Based Studies. Biomolecules 2017; 7:biom7010019. [PMID: 28230817 PMCID: PMC5372731 DOI: 10.3390/biom7010019] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 02/10/2017] [Indexed: 01/01/2023] Open
Abstract
DNA replication is a highly demanding process regarding the energy and material supply and must be precisely regulated, involving multiple cellular feedbacks. The slowing down or stalling of DNA synthesis and/or replication forks is referred to as replication stress (RS). Owing to the complexity and requirements of replication, a plethora of factors may interfere and challenge the genome stability, cell survival or affect the whole organism. This review outlines chemical compounds that are known inducers of RS and commonly used in laboratory research. These compounds act on replication by direct interaction with DNA causing DNA crosslinks and bulky lesions (cisplatin), chemical interference with the metabolism of deoxyribonucleotide triphosphates (hydroxyurea), direct inhibition of the activity of replicative DNA polymerases (aphidicolin) and interference with enzymes dealing with topological DNA stress (camptothecin, etoposide). As a variety of mechanisms can induce RS, the responses of mammalian cells also vary. Here, we review the activity and mechanism of action of these compounds based on recent knowledge, accompanied by examples of induced phenotypes, cellular readouts and commonly used doses.
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S-phase checkpoint regulations that preserve replication and chromosome integrity upon dNTP depletion. Cell Mol Life Sci 2017; 74:2361-2380. [PMID: 28220209 PMCID: PMC5487892 DOI: 10.1007/s00018-017-2474-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 12/29/2016] [Accepted: 01/23/2017] [Indexed: 11/18/2022]
Abstract
DNA replication stress, an important source of genomic instability, arises upon different types of DNA replication perturbations, including those that stall replication fork progression. Inhibitors of the cellular pool of deoxynucleotide triphosphates (dNTPs) slow down DNA synthesis throughout the genome. Following depletion of dNTPs, the highly conserved replication checkpoint kinase pathway, also known as the S-phase checkpoint, preserves the functionality and structure of stalled DNA replication forks and prevents chromosome fragmentation. The underlying mechanisms involve pathways extrinsic to replication forks, such as those involving regulation of the ribonucleotide reductase activity, the temporal program of origin firing, and cell cycle transitions. In addition, the S-phase checkpoint modulates the function of replisome components to promote replication integrity. This review summarizes the various functions of the replication checkpoint in promoting replication fork stability and genome integrity in the face of replication stress caused by dNTP depletion.
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42
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Madireddy A, Gerhardt J. Replication Through Repetitive DNA Elements and Their Role in Human Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1042:549-581. [PMID: 29357073 DOI: 10.1007/978-981-10-6955-0_23] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Human cells contain various repetitive DNA sequences, which can be a challenge for the DNA replication machinery to travel through and replicate correctly. Repetitive DNA sequence can adopt non-B DNA structures, which could block the DNA replication. Prolonged stalling of the replication fork at the endogenous repeats in human cells can have severe consequences such as genome instability that includes repeat expansions, contractions, and chromosome fragility. Several neurological and muscular diseases are caused by a repeat expansion. Furthermore genome instability is the major cause of cancer. This chapter describes some of the important classes of repetitive DNA sequences in the mammalian genome, their ability to form secondary DNA structures, their contribution to replication fork stalling, and models for repeat expansion as well as chromosomal fragility. Included in this chapter are also some of the strategies currently employed to detect changes in DNA replication and proteins that could prevent the repeat-mediated disruption of DNA replication in human cells. Additionally summarized are the consequences of repeat-associated perturbation of the DNA replication, which could lead to specific human diseases.
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Vindigni A, Lopes M. Combining electron microscopy with single molecule DNA fiber approaches to study DNA replication dynamics. Biophys Chem 2016; 225:3-9. [PMID: 27939387 DOI: 10.1016/j.bpc.2016.11.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 11/30/2016] [Accepted: 11/30/2016] [Indexed: 10/20/2022]
Abstract
Replication stress is a crucial driver of genomic instability. Understanding the mechanisms of replication stress response is instrumental to improve diagnosis and treatment of human disease. Electron microscopy (EM) is currently the technique of choice to directly visualize a high number of replication intermediates and to monitor their remodeling upon stress. At the same time, DNA fiber analysis is useful to gain mechanistic insight on how genotoxic agents perturb replication fork dynamics genome-wide at single-molecule resolution. Combining these techniques has proven invaluable to achieve a comprehensive view of the mechanisms that ensure error-free processing of damaged replication forks. Here, we review how EM and single-molecule DNA fiber approaches can be used together to shed light into the mechanisms of replication stress response and discuss important cautions to be taken into account when comparing results obtained by EM and DNA fiber.
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Affiliation(s)
- Alessandro Vindigni
- Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA.
| | - Massimo Lopes
- Institute of Molecular Cancer Research, University of Zurich, 8057 Zurich, Switzerland.
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Fradet-Turcotte A, Sitz J, Grapton D, Orthwein A. BRCA2 functions: from DNA repair to replication fork stabilization. Endocr Relat Cancer 2016; 23:T1-T17. [PMID: 27530658 DOI: 10.1530/erc-16-0297] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Accepted: 08/16/2016] [Indexed: 12/12/2022]
Abstract
Maintaining genomic integrity is essential to preserve normal cellular physiology and to prevent the emergence of several human pathologies including cancer. The breast cancer susceptibility gene 2 (BRCA2, also known as the Fanconi anemia (FA) complementation group D1 (FANCD1)) is a potent tumor suppressor that has been extensively studied in DNA double-stranded break (DSB) repair by homologous recombination (HR). However, BRCA2 participates in numerous other processes central to maintaining genome stability, including DNA replication, telomere homeostasis and cell cycle progression. Consequently, inherited mutations in BRCA2 are associated with an increased risk of breast, ovarian and pancreatic cancers. Furthermore, bi-allelic mutations in BRCA2 are linked to FA, a rare chromosome instability syndrome characterized by aplastic anemia in children as well as susceptibility to leukemia and cancer. Here, we discuss the recent developments underlying the functions of BRCA2 in the maintenance of genomic integrity. The current model places BRCA2 as a central regulator of genome stability by repairing DSBs and limiting replication stress. These findings have direct implications for the development of novel anticancer therapeutic approaches.
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Affiliation(s)
- Amélie Fradet-Turcotte
- Laval University Cancer Research CenterCHU de Québec Research Center - Université Laval, Hôtel-Dieu de Québec, Oncology Axis, Quebec City, Canada
| | - Justine Sitz
- Laval University Cancer Research CenterCHU de Québec Research Center - Université Laval, Hôtel-Dieu de Québec, Oncology Axis, Quebec City, Canada
| | - Damien Grapton
- Lady Davis Institute for Medical ResearchSegal Cancer Centre, Jewish General Hospital, Montreal, Canada
| | - Alexandre Orthwein
- Lady Davis Institute for Medical ResearchSegal Cancer Centre, Jewish General Hospital, Montreal, Canada Department of OncologyMcGill University, Montreal, Canada
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45
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Sato K, Shimomuki M, Katsuki Y, Takahashi D, Kobayashi W, Ishiai M, Miyoshi H, Takata M, Kurumizaka H. FANCI-FANCD2 stabilizes the RAD51-DNA complex by binding RAD51 and protects the 5'-DNA end. Nucleic Acids Res 2016; 44:10758-10771. [PMID: 27694619 PMCID: PMC5159555 DOI: 10.1093/nar/gkw876] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 08/22/2016] [Accepted: 09/21/2016] [Indexed: 01/12/2023] Open
Abstract
The FANCI-FANCD2 (I-D) complex is considered to work with RAD51 to protect the damaged DNA in the stalled replication fork. However, the means by which this DNA protection is accomplished have remained elusive. In the present study, we found that the I-D complex directly binds to RAD51, and stabilizes the RAD51-DNA filament. Unexpectedly, the DNA binding activity of FANCI, but not FANCD2, is explicitly required for the I-D complex-mediated RAD51-DNA filament stabilization. The RAD51 filament stabilized by the I-D complex actually protects the DNA end from nucleolytic degradation by an FA-associated nuclease, FAN1. This DNA end protection is not observed with the RAD51 mutant from FANCR patient cells. These results clearly answer the currently enigmatic question of how RAD51 functions with the I-D complex to prevent genomic instability at the stalled replication fork.
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Affiliation(s)
- Koichi Sato
- Laboratory of Structural Biology, Graduate School of Advanced Science & Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Mayo Shimomuki
- Laboratory of Structural Biology, Graduate School of Advanced Science & Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Yoko Katsuki
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Kyoto University, Kyoto 606-8501, Japan
| | - Daisuke Takahashi
- Laboratory of Structural Biology, Graduate School of Advanced Science & Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Wataru Kobayashi
- Laboratory of Structural Biology, Graduate School of Advanced Science & Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Masamichi Ishiai
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Kyoto University, Kyoto 606-8501, Japan
| | - Hiroyuki Miyoshi
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Minoru Takata
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Kyoto University, Kyoto 606-8501, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Structural Biology, Graduate School of Advanced Science & Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan .,Institute for Medical-oriented Structural Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
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46
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Lopez-Martinez D, Liang CC, Cohn MA. Cellular response to DNA interstrand crosslinks: the Fanconi anemia pathway. Cell Mol Life Sci 2016; 73:3097-114. [PMID: 27094386 PMCID: PMC4951507 DOI: 10.1007/s00018-016-2218-x] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 04/04/2016] [Accepted: 04/05/2016] [Indexed: 12/22/2022]
Abstract
Interstrand crosslinks (ICLs) are a highly toxic form of DNA damage. ICLs can interfere with vital biological processes requiring separation of the two DNA strands, such as replication and transcription. If ICLs are left unrepaired, it can lead to mutations, chromosome breakage and mitotic catastrophe. The Fanconi anemia (FA) pathway can repair this type of DNA lesion, ensuring genomic stability. In this review, we will provide an overview of the cellular response to ICLs. First, we will discuss the origin of ICLs, comparing various endogenous and exogenous sources. Second, we will describe FA proteins as well as FA-related proteins involved in ICL repair, and the post-translational modifications that regulate these proteins. Finally, we will review the process of how ICLs are repaired by both replication-dependent and replication-independent mechanisms.
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Affiliation(s)
- David Lopez-Martinez
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Chih-Chao Liang
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Martin A Cohn
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
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47
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Thongthip S, Bellani M, Gregg SQ, Sridhar S, Conti BA, Chen Y, Seidman MM, Smogorzewska A. Fan1 deficiency results in DNA interstrand cross-link repair defects, enhanced tissue karyomegaly, and organ dysfunction. Genes Dev 2016; 30:645-59. [PMID: 26980189 PMCID: PMC4803051 DOI: 10.1101/gad.276261.115] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Thongthip et al. describe a FANCD2/FANCI-associated nuclease 1 (Fan1)-deficient mouse and show that FAN1 is required for cellular and organismal resistance to DNA interstrand cross-links. Karyomegaly becomes prominent in the kidneys and livers of Fan1-deficient mice with age, and mice develop liver dysfunction. Deficiency of FANCD2/FANCI-associated nuclease 1 (FAN1) in humans leads to karyomegalic interstitial nephritis (KIN), a rare hereditary kidney disease characterized by chronic renal fibrosis, tubular degeneration, and characteristic polyploid nuclei in multiple tissues. The mechanism of how FAN1 protects cells is largely unknown but is thought to involve FAN1's function in DNA interstrand cross-link (ICL) repair. Here, we describe a Fan1-deficient mouse and show that FAN1 is required for cellular and organismal resistance to ICLs. We show that the ubiquitin-binding zinc finger (UBZ) domain of FAN1, which is needed for interaction with FANCD2, is not required for the initial rapid recruitment of FAN1 to ICLs or for its role in DNA ICL resistance. Epistasis analyses reveal that FAN1 has cross-link repair activities that are independent of the Fanconi anemia proteins and that this activity is redundant with the 5′–3′ exonuclease SNM1A. Karyomegaly becomes prominent in kidneys and livers of Fan1-deficient mice with age, and mice develop liver dysfunction. Treatment of Fan1-deficient mice with ICL-inducing agents results in pronounced thymic and bone marrow hypocellularity and the disappearance of c-kit+ cells. Our results provide insight into the mechanism of FAN1 in ICL repair and demonstrate that the Fan1 mouse model effectively recapitulates the pathological features of human FAN1 deficiency.
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Affiliation(s)
- Supawat Thongthip
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| | - Marina Bellani
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Siobhan Q Gregg
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| | - Sunandini Sridhar
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| | - Brooke A Conti
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| | - Yanglu Chen
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| | - Michael M Seidman
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Agata Smogorzewska
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
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48
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Kais Z, Rondinelli B, Holmes A, O'Leary C, Kozono D, D'Andrea AD, Ceccaldi R. FANCD2 Maintains Fork Stability in BRCA1/2-Deficient Tumors and Promotes Alternative End-Joining DNA Repair. Cell Rep 2016; 15:2488-99. [PMID: 27264184 PMCID: PMC4939765 DOI: 10.1016/j.celrep.2016.05.031] [Citation(s) in RCA: 139] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 03/28/2016] [Accepted: 05/05/2016] [Indexed: 11/21/2022] Open
Abstract
BRCA1/2 proteins function in homologous recombination (HR)-mediated DNA repair and cooperate with Fanconi anemia (FA) proteins to maintain genomic integrity through replication fork stabilization. Loss of BRCA1/2 proteins results in DNA repair deficiency and replicative stress, leading to genomic instability and enhanced sensitivity to DNA-damaging agents. Recent studies have shown that BRCA1/2-deficient tumors upregulate Polθ-mediated alternative end-joining (alt-EJ) repair as a survival mechanism. Whether other mechanisms maintain genomic integrity upon loss of BRCA1/2 proteins is currently unknown. Here we show that BRCA1/2-deficient tumors also upregulate FANCD2 activity. FANCD2 is required for fork protection and fork restart in BRCA1/2-deficient tumors. Moreover, FANCD2 promotes Polθ recruitment at sites of damage and alt-EJ repair. Finally, loss of FANCD2 in BRCA1/2-deficient tumors enhances cell death. These results reveal a synthetic lethal relationship between FANCD2 and BRCA1/2, and they identify FANCD2 as a central player orchestrating DNA repair pathway choice at the replication fork.
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Affiliation(s)
- Zeina Kais
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Beatrice Rondinelli
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Amie Holmes
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Colin O'Leary
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - David Kozono
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Alan D D'Andrea
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA; Center for DNA Damage and Repair, Dana-Farber Cancer Institute, Boston, MA 02215, USA.
| | - Raphael Ceccaldi
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA.
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49
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Ceccaldi R, Sarangi P, D'Andrea AD. The Fanconi anaemia pathway: new players and new functions. Nat Rev Mol Cell Biol 2016; 17:337-49. [PMID: 27145721 DOI: 10.1038/nrm.2016.48] [Citation(s) in RCA: 488] [Impact Index Per Article: 61.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The Fanconi anaemia pathway repairs DNA interstrand crosslinks (ICLs) in the genome. Our understanding of this complex pathway is still evolving, as new components continue to be identified and new biochemical systems are used to elucidate the molecular steps of repair. The Fanconi anaemia pathway uses components of other known DNA repair processes to achieve proper repair of ICLs. Moreover, Fanconi anaemia proteins have functions in genome maintenance beyond their canonical roles of repairing ICLs. Such functions include the stabilization of replication forks and the regulation of cytokinesis. Thus, Fanconi anaemia proteins are emerging as master regulators of genomic integrity that coordinate several repair processes. Here, we summarize our current understanding of the functions of the Fanconi anaemia pathway in ICL repair, together with an overview of its connections with other repair pathways and its emerging roles in genome maintenance.
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Affiliation(s)
- Raphael Ceccaldi
- Department of Radiation Oncology and Center for DNA Damage and Repair, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02215, USA
| | - Prabha Sarangi
- Department of Radiation Oncology and Center for DNA Damage and Repair, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02215, USA
| | - Alan D D'Andrea
- Department of Radiation Oncology and Center for DNA Damage and Repair, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02215, USA
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50
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Lachaud C, Moreno A, Marchesi F, Toth R, Blow JJ, Rouse J. Ubiquitinated Fancd2 recruits Fan1 to stalled replication forks to prevent genome instability. Science 2016; 351:846-9. [PMID: 26797144 PMCID: PMC4770513 DOI: 10.1126/science.aad5634] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 01/11/2016] [Indexed: 12/18/2022]
Abstract
Mono-ubiquitination of Fancd2 is essential for repairing DNA interstrand cross-links (ICLs), but the underlying mechanisms are unclear. The Fan1 nuclease, also required for ICL repair, is recruited to ICLs by ubiquitinated (Ub) Fancd2. This could in principle explain how Ub-Fancd2 promotes ICL repair, but we show that recruitment of Fan1 by Ub-Fancd2 is dispensable for ICL repair. Instead, Fan1 recruitment--and activity--restrains DNA replication fork progression and prevents chromosome abnormalities from occurring when DNA replication forks stall, even in the absence of ICLs. Accordingly, Fan1 nuclease-defective knockin mice are cancer-prone. Moreover, we show that a Fan1 variant in high-risk pancreatic cancers abolishes recruitment by Ub-Fancd2 and causes genetic instability without affecting ICL repair. Therefore, Fan1 recruitment enables processing of stalled forks that is essential for genome stability and health.
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Affiliation(s)
- Christophe Lachaud
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, Sir James Black Centre, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Alberto Moreno
- Centre for Gene Regulation and Expression, College of Life Sciences, Sir James Black Centre, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Francesco Marchesi
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bearsden Road, Glasgow G61 1QH, UK
| | - Rachel Toth
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, Sir James Black Centre, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - J Julian Blow
- Centre for Gene Regulation and Expression, College of Life Sciences, Sir James Black Centre, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - John Rouse
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, Sir James Black Centre, University of Dundee, Dundee DD1 5EH, Scotland, UK.
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