1
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Lee JH. Targeting the ATM pathway in cancer: Opportunities, challenges and personalized therapeutic strategies. Cancer Treat Rev 2024; 129:102808. [PMID: 39106770 DOI: 10.1016/j.ctrv.2024.102808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2024] [Revised: 07/29/2024] [Accepted: 07/30/2024] [Indexed: 08/09/2024]
Abstract
Ataxia telangiectasia mutated (ATM) kinase plays a pivotal role in orchestrating the DNA damage response, maintaining genomic stability, and regulating various cellular processes. This review provides a comprehensive analysis of ATM's structure, activation mechanisms, and various functions in cancer development, progression, and treatment. I discuss ATM's dual nature as both a tumor suppressor and potential promoter of cancer cell survival in certain contexts. The article explores the complex signaling pathways mediated by ATM, its interactions with other DNA repair mechanisms, and its influence on cell cycle checkpoints, apoptosis, and metabolism. I examine the clinical implications of ATM alterations, including their impact on cancer predisposition, prognosis, and treatment response. The review highlights recent advances in ATM-targeted therapies, discussing ongoing clinical trials of ATM inhibitors and their potential in combination with other treatment modalities. I also address the challenges in developing effective biomarkers for ATM activity and patient selection strategies for personalized cancer therapy. Finally, I outline future research directions, emphasizing the need for refined biomarker development, optimized combination therapies, and strategies to overcome potential resistance mechanisms. This comprehensive overview underscores the critical importance of ATM in cancer biology and its emerging potential as a therapeutic target in precision oncology.
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Affiliation(s)
- Ji-Hoon Lee
- Department of Biological Sciences, Research Center of Ecomimetics, Chonnam National University, Gwangju 61186, Republic of Korea.
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2
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de la Peña Avalos B, Paquet N, Tropée R, Coulombe Y, Palacios H, Leung J, Masson JY, Duijf PG, Dray E. The protein phosphatase EYA4 promotes homologous recombination (HR) through dephosphorylation of tyrosine 315 on RAD51. Nucleic Acids Res 2024; 52:1173-1187. [PMID: 38084915 PMCID: PMC10853800 DOI: 10.1093/nar/gkad1177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 11/20/2023] [Accepted: 11/27/2023] [Indexed: 01/07/2024] Open
Abstract
Efficient DNA repair and limitation of genome rearrangements rely on crosstalk between different DNA double-strand break (DSB) repair pathways, and their synchronization with the cell cycle. The selection, timing and efficacy of DSB repair pathways are influenced by post-translational modifications of histones and DNA damage repair (DDR) proteins, such as phosphorylation. While the importance of kinases and serine/threonine phosphatases in DDR have been extensively studied, the role of tyrosine phosphatases in DNA repair remains poorly understood. In this study, we have identified EYA4 as the protein phosphatase that dephosphorylates RAD51 on residue Tyr315. Through its Tyr phosphatase activity, EYA4 regulates RAD51 localization, presynaptic filament formation, foci formation, and activity. Thus, it is essential for homologous recombination (HR) at DSBs. DNA binding stimulates EYA4 phosphatase activity. Depletion of EYA4 decreases single-stranded DNA accumulation following DNA damage and impairs HR, while overexpression of EYA4 in cells promotes dephosphorylation and stabilization of RAD51, and thereby nucleoprotein filament formation. Our data have implications for a pathological version of RAD51 in EYA4-overexpressing cancers.
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Affiliation(s)
- Bárbara de la Peña Avalos
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Mays Cancer Center at UT Health San Antonio MD Anderson, San Antonio, TX, USA
| | - Nicolas Paquet
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Romain Tropée
- Queensland University of Technology, Translational Research Institute, Brisbane, QLD, Australia
| | - Yan Coulombe
- Genome Stability Laboratory, CHU de Québec Research Center, HDQ Pavilion, Oncology Division, Québec City, QC, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Laval University Cancer Research Center, Québec City, QC, Canada
| | - Hannah Palacios
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Justin W Leung
- Department of Radiation Oncology, University of Texas Health and Science Center, San Antonio, TX 78229, USA
| | - Jean-Yves Masson
- Genome Stability Laboratory, CHU de Québec Research Center, HDQ Pavilion, Oncology Division, Québec City, QC, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Laval University Cancer Research Center, Québec City, QC, Canada
| | - Pascal H G Duijf
- Centre for Cancer Biology, Clinical and Health Sciences, University of South Australia & SA Pathology, Adelaide SA, Australia
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Medical Genetics, Oslo University Hospital, Oslo, Norway
| | - Eloïse Dray
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Mays Cancer Center at UT Health San Antonio MD Anderson, San Antonio, TX, USA
- Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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3
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Schwarz B, Matejka N, Rudigkeit S, Sammer M, Reindl J. Chromatin Organization after High-LET Irradiation Revealed by Super-Resolution STED Microscopy. Int J Mol Sci 2024; 25:628. [PMID: 38203799 PMCID: PMC10779204 DOI: 10.3390/ijms25010628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 12/15/2023] [Accepted: 12/27/2023] [Indexed: 01/12/2024] Open
Abstract
Ion-radiation-induced DNA double-strand breaks can lead to severe cellular damage ranging from mutations up to direct cell death. The interplay between the chromatin surrounding the damage and the proteins responsible for damage recognition and repair determines the efficiency and outcome of DNA repair. The chromatin is organized in three major functional compartments throughout the interphase: the chromatin territories, the interchromatin compartment, and the perichromatin lying in between. In this study, we perform correlation analysis using super-resolution STED images of chromatin; splicing factor SC35, as an interchromatin marker; and the DNA repair factors 53BP1, Rad51, and γH2AX in carbon-ion-irradiated human HeLa cells. Chromatin and interchromatin overlap only in protruding chromatin branches, which is the same for the correlation between chromatin and 53BP1. In contrast, between interchromatin and 53BP1, a gap of (270 ± 40) nm is visible. Rad51 shows overlap with decondensed euchromatic regions located at the borders of condensed heterochromatin with further correlation with γH2AX. We conclude that the DNA damage is repaired in decondensed DNA loops in the perichromatin, located in the periphery of the DNA-dense chromatin compartments containing the heterochromatin. Proteins like γH2AX and 53BP1 serve as supporters of the chromatin structure.
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García Fernández F, Huet S, Miné-Hattab J. Multi-Scale Imaging of the Dynamic Organization of Chromatin. Int J Mol Sci 2023; 24:15975. [PMID: 37958958 PMCID: PMC10649806 DOI: 10.3390/ijms242115975] [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: 09/19/2023] [Revised: 10/27/2023] [Accepted: 10/27/2023] [Indexed: 11/15/2023] Open
Abstract
Chromatin is now regarded as a heterogeneous and dynamic structure occupying a non-random position within the cell nucleus, where it plays a key role in regulating various functions of the genome. This current view of chromatin has emerged thanks to high spatiotemporal resolution imaging, among other new technologies developed in the last decade. In addition to challenging early assumptions of chromatin being regular and static, high spatiotemporal resolution imaging made it possible to visualize and characterize different chromatin structures such as clutches, domains and compartments. More specifically, super-resolution microscopy facilitates the study of different cellular processes at a nucleosome scale, providing a multi-scale view of chromatin behavior within the nucleus in different environments. In this review, we describe recent imaging techniques to study the dynamic organization of chromatin at high spatiotemporal resolution. We also discuss recent findings, elucidated by these techniques, on the chromatin landscape during different cellular processes, with an emphasis on the DNA damage response.
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Affiliation(s)
- Fabiola García Fernández
- Laboratory of Computational and Quantitative Biology, CNRS, Institut de Biologie Paris-Seine, Sorbonne Université, 75005 Paris, France;
| | - Sébastien Huet
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes)-UMR 6290, BIOSIT-UMS 3480, 35000 Rennes, France;
- Institut Universitaire de France, 75231 Paris, France
| | - Judith Miné-Hattab
- Laboratory of Computational and Quantitative Biology, CNRS, Institut de Biologie Paris-Seine, Sorbonne Université, 75005 Paris, France;
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5
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Arnould C, Rocher V, Saur F, Bader AS, Muzzopappa F, Collins S, Lesage E, Le Bozec B, Puget N, Clouaire T, Mangeat T, Mourad R, Ahituv N, Noordermeer D, Erdel F, Bushell M, Marnef A, Legube G. Chromatin compartmentalization regulates the response to DNA damage. Nature 2023; 623:183-192. [PMID: 37853125 PMCID: PMC10620078 DOI: 10.1038/s41586-023-06635-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 09/12/2023] [Indexed: 10/20/2023]
Abstract
The DNA damage response is essential to safeguard genome integrity. Although the contribution of chromatin in DNA repair has been investigated1,2, the contribution of chromosome folding to these processes remains unclear3. Here we report that, after the production of double-stranded breaks (DSBs) in mammalian cells, ATM drives the formation of a new chromatin compartment (D compartment) through the clustering of damaged topologically associating domains, decorated with γH2AX and 53BP1. This compartment forms by a mechanism that is consistent with polymer-polymer phase separation rather than liquid-liquid phase separation. The D compartment arises mostly in G1 phase, is independent of cohesin and is enhanced after pharmacological inhibition of DNA-dependent protein kinase (DNA-PK) or R-loop accumulation. Importantly, R-loop-enriched DNA-damage-responsive genes physically localize to the D compartment, and this contributes to their optimal activation, providing a function for DSB clustering in the DNA damage response. However, DSB-induced chromosome reorganization comes at the expense of an increased rate of translocations, also observed in cancer genomes. Overall, we characterize how DSB-induced compartmentalization orchestrates the DNA damage response and highlight the critical impact of chromosome architecture in genomic instability.
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Affiliation(s)
- Coline Arnould
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
- Institute for Human Genetics, University of California, San Francisco, San Francisco, CA, USA
| | - Vincent Rocher
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Florian Saur
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Aldo S Bader
- Cancer Research UK Beatson Institute, Glasgow, UK
| | - Fernando Muzzopappa
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Sarah Collins
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Emma Lesage
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Benjamin Le Bozec
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Nadine Puget
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Thomas Clouaire
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Thomas Mangeat
- LITC Core Facility, Centre de Biologie Integrative, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Raphael Mourad
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Nadav Ahituv
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
- Institute for Human Genetics, University of California, San Francisco, San Francisco, CA, USA
| | - Daan Noordermeer
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Fabian Erdel
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Martin Bushell
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Aline Marnef
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Gaëlle Legube
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France.
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6
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Rose JC, Wong ITL, Daniel B, Jones MG, Yost KE, Hung KL, Curtis EJ, Mischel PS, Chang HY. Disparate pathways for extrachromosomal DNA biogenesis and genomic DNA repair. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.22.563489. [PMID: 37961138 PMCID: PMC10634728 DOI: 10.1101/2023.10.22.563489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Oncogene amplification on extrachromosomal DNA (ecDNA) is a pervasive driver event in cancer, yet our understanding of how ecDNA forms is limited. Here, we couple a CRISPR-based method for induction of ecDNA with extensive characterization of newly formed ecDNA to examine ecDNA biogenesis. We find that DNA circularization is efficient, irrespective of 3D genome context, with formation of a 1 Mb and 1.8 Mb ecDNA both reaching 15%. We show non-homologous end joining and microhomology mediated end joining both contribute to ecDNA formation, while inhibition of DNA-PKcs and ATM have opposing impacts on ecDNA formation. EcDNA and the corresponding chromosomal excision scar form at significantly different rates and respond differently to DNA-PKcs and ATM inhibition. Taken together, our results support a model of ecDNA formation in which double strand break ends dissociate from their legitimate ligation partners prior to joining of illegitimate ends to form the ecDNA and excision scar.
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Affiliation(s)
- John C Rose
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA, USA
| | - Ivy Tsz-Lo Wong
- Sarafan ChEM-H, Stanford University, Stanford, CA, USA
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA
| | - Bence Daniel
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA, USA
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA
| | - Matthew G Jones
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA, USA
| | - Kathryn E Yost
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA, USA
| | - King L Hung
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA, USA
| | - Ellis J Curtis
- Sarafan ChEM-H, Stanford University, Stanford, CA, USA
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA
| | - Paul S Mischel
- Sarafan ChEM-H, Stanford University, Stanford, CA, USA
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA
| | - Howard Y Chang
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford, CA, USA
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7
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Elser M, Vehlow A, Juratli TA, Cordes N. Simultaneous inhibition of discoidin domain receptor 1 and integrin αVβ3 radiosensitizes human glioblastoma cells. Am J Cancer Res 2023; 13:4597-4612. [PMID: 37970361 PMCID: PMC10636682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 08/13/2023] [Indexed: 11/17/2023] Open
Abstract
Glioblastomas (GBM) are the most common primary brain tumors in adults and associated with poor clinical outcomes due to therapy resistances and destructive growth. Interactions of cancer cells with the extracellular matrix (ECM) play a pivotal role in therapy resistances and tumor progression. In this study, we investigate the functional dependencies between the discoidin domain receptor 1 (DDR1) and the integrin family of cell adhesion molecules for the radioresponse of human glioblastoma cells. By means of an RNA interference screen on DDR1 and all known integrin subunits, we identified co-targeting of DDR1/integrin β3 to most efficiently reduce clonogenicity, enhance cellular radiosensitivity and diminish repair of DNA double strand breaks (DSB). Simultaneous pharmacological inhibition of DDR1 with DDR1-IN-1 and of integrins αVβ3/αVβ5 with cilengitide resulted in confirmatory data in a panel of 2D grown glioblastoma cultures and 3D gliospheres. Mechanistically, we found that key DNA repair proteins ATM and DNA-PK are altered upon DDR1/integrin αVβ3/integrin αVβ5 inhibition, suggesting a link to DNA repair mechanisms. In sum, the radioresistance of human glioblastoma cells can effectively be declined by co-deactivation of DDR1, integrin αVβ3 and integrin αVβ5.
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Affiliation(s)
- Marc Elser
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden01307 Dresden, Germany
| | - Anne Vehlow
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden01307 Dresden, Germany
| | - Tareq A Juratli
- Department of Neurosurgery, Division of Neuro-Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden01307 Dresden, Germany
| | - Nils Cordes
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden01307 Dresden, Germany
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiooncology-OncoRay01328 Dresden, Germany
- German Cancer Consortium, Partner Site Dresden, German Cancer Research Center69120 Heidelberg, Germany
- Department of Radiotherapy and Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden01307 Dresden, Germany
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8
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Canoy RJ, Shmakova A, Karpukhina A, Lomov N, Tiukacheva E, Kozhevnikova Y, André F, Germini D, Vassetzky Y. Specificity of cancer-related chromosomal translocations is linked to proximity after the DNA double-strand break and subsequent selection. NAR Cancer 2023; 5:zcad049. [PMID: 37750169 PMCID: PMC10518054 DOI: 10.1093/narcan/zcad049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 08/01/2023] [Accepted: 09/14/2023] [Indexed: 09/27/2023] Open
Abstract
Most cancer-related chromosomal translocations appear to be cell type specific. It is currently unknown why different chromosomal translocations occur in different cells. This can be due to either the occurrence of particular translocations in specific cell types or adaptive survival advantage conferred by translocations only in specific cells. We experimentally addressed this question by double-strand break (DSB) induction at MYC, IGH, AML and ETO loci in the same cell to generate chromosomal translocations in different cell lineages. Our results show that any translocation can potentially arise in any cell type. We have analyzed different factors that could affect the frequency of the translocations, and only the spatial proximity between gene loci after the DSB induction correlated with the resulting translocation frequency, supporting the 'breakage-first' model. Furthermore, upon long-term culture of cells with the generated chromosomal translocations, only oncogenic MYC-IGH and AML-ETO translocations persisted over a 60-day period. Overall, the results suggest that chromosomal translocation can be generated after DSB induction in any type of cell, but whether the cell with the translocation would persist in a cell population depends on the cell type-specific selective survival advantage that the chromosomal translocation confers to the cell.
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Affiliation(s)
- Reynand Jay Canoy
- UMR 9018, CNRS, Univ. Paris-Sud, Université Paris Saclay, Institut Gustave Roussy, F-94805 Villejuif, France
- Institute of Human Genetics, National Institutes of Health, University of the Philippines Manila, 1000 Manila, The Philippines
| | - Anna Shmakova
- UMR 9018, CNRS, Univ. Paris-Sud, Université Paris Saclay, Institut Gustave Roussy, F-94805 Villejuif, France
- Laboratory of Molecular Endocrinology, Institute of Experimental Cardiology, Federal State Budgetary Organization ‘National Cardiology Research Center’ of the Ministry of Health of the Russian Federation, 127994 Moscow, Russia
- Koltzov Institute of Developmental Biology, 117334 Moscow, Russia
| | - Anna Karpukhina
- UMR 9018, CNRS, Univ. Paris-Sud, Université Paris Saclay, Institut Gustave Roussy, F-94805 Villejuif, France
- Koltzov Institute of Developmental Biology, 117334 Moscow, Russia
| | - Nikolai Lomov
- Department of Molecular Biology, Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Eugenia Tiukacheva
- UMR 9018, CNRS, Univ. Paris-Sud, Université Paris Saclay, Institut Gustave Roussy, F-94805 Villejuif, France
- Koltzov Institute of Developmental Biology, 117334 Moscow, Russia
| | - Yana Kozhevnikova
- UMR 9018, CNRS, Univ. Paris-Sud, Université Paris Saclay, Institut Gustave Roussy, F-94805 Villejuif, France
| | - Franck André
- UMR 9018, CNRS, Univ. Paris-Sud, Université Paris Saclay, Institut Gustave Roussy, F-94805 Villejuif, France
| | - Diego Germini
- UMR 9018, CNRS, Univ. Paris-Sud, Université Paris Saclay, Institut Gustave Roussy, F-94805 Villejuif, France
| | - Yegor Vassetzky
- UMR 9018, CNRS, Univ. Paris-Sud, Université Paris Saclay, Institut Gustave Roussy, F-94805 Villejuif, France
- Koltzov Institute of Developmental Biology, 117334 Moscow, Russia
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9
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Lu H, Zhang Q, Laverty DJ, Puncheon AC, Augustine M, Williams G, Nagel Z, Chen BC, Davis A. ATM phosphorylates the FATC domain of DNA-PKcs at threonine 4102 to promote non-homologous end joining. Nucleic Acids Res 2023; 51:6770-6783. [PMID: 37309889 PMCID: PMC10359628 DOI: 10.1093/nar/gkad505] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 05/26/2023] [Accepted: 05/31/2023] [Indexed: 06/14/2023] Open
Abstract
Ataxia-telangiectasia mutated (ATM) drives the DNA damage response via modulation of multiple signal transduction and DNA repair pathways. Previously, ATM activity was implicated in promoting the non-homologous end joining (NHEJ) pathway to repair a subset of DNA double-stranded breaks (DSBs), but how ATM performs this function is still unclear. In this study, we identified that ATM phosphorylates the DNA-dependent protein kinase catalytic subunit (DNA-PKcs), a core NHEJ factor, at its extreme C-terminus at threonine 4102 (T4102) in response to DSBs. Ablating phosphorylation at T4102 attenuates DNA-PKcs kinase activity and this destabilizes the interaction between DNA-PKcs and the Ku-DNA complex, resulting in decreased assembly and stabilization of the NHEJ machinery at DSBs. Phosphorylation at T4102 promotes NHEJ, radioresistance, and increases genomic stability following DSB induction. Collectively, these findings establish a key role for ATM in NHEJ-dependent repair of DSBs through positive regulation of DNA-PKcs.
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Affiliation(s)
- Huiming Lu
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX75390, USA
| | - Qin Zhang
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX75390, USA
| | - Daniel J Laverty
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA02115, USA
| | - Andrew C Puncheon
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX75390, USA
| | - Mathew M Augustine
- Division of Surgical Oncology, Department of Surgery, UT Southwestern Medical Center, Dallas, TX75390, USA
- Department of Surgery, North Texas VA Medical Center, Dallas, TX75216, USA
| | - Gareth J Williams
- Department of Biochemistry and Molecular Biology, Robson DNA Science Centre, Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Zachary D Nagel
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA02115, USA
| | - Benjamin P C Chen
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX75390, USA
| | - Anthony J Davis
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX75390, USA
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10
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Lv X, Mao Z, Sun X, Liu B. Intratumoral Heterogeneity in Lung Cancer. Cancers (Basel) 2023; 15:2709. [PMID: 37345046 DOI: 10.3390/cancers15102709] [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: 04/19/2023] [Revised: 05/07/2023] [Accepted: 05/09/2023] [Indexed: 06/23/2023] Open
Abstract
The diagnosis and treatment of lung cancer (LC) is always a challenge. The difficulty in the decision of therapeutic schedule and diagnosis is directly related to intratumoral heterogeneity (ITH) in the progression of LC. It has been proven that most tumors emerge and evolve under the pressure of their living microenvironment, which involves genetic, immunological, metabolic, and therapeutic components. While most research on ITH revealed multiple mechanisms and characteristic, a systemic exposition of ITH in LC is still hard to find. In this review, we describe how ITH in LC develops from the perspective of space and time. We discuss elaborate details and affection of every aspect of ITH in LC and the relationship between them. Based on ITH in LC, we describe a more accurate multidisciplinary therapeutic strategy on LC and provide the newest opinion on the potential approach of LC therapy.
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Affiliation(s)
- Xiaodi Lv
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai 200437, China
| | - Zixian Mao
- Pujiang Community Health Center of Minhang District of Shanghai, Shanghai 201114, China
| | - Xianjun Sun
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai 200437, China
- Institutes of Integrative Medicine, Fudan University, Shanghai 200437, China
| | - Baojun Liu
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai 200437, China
- Institutes of Integrative Medicine, Fudan University, Shanghai 200437, China
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11
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Lu H, Zhang Q, Laverty DJ, Puncheon AC, Williams GJ, Nagel ZD, Chen BP, Davis AJ. ATM phosphorylates the FATC domain of DNA-PK cs at threonine 4102 to promote non-homologous end joining. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.02.526879. [PMID: 36778257 PMCID: PMC9915669 DOI: 10.1101/2023.02.02.526879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Ataxia-telangiectasia mutated (ATM) drives the DNA damage response via modulation of multiple signal transduction and DNA repair pathways. Previously, ATM activity was implicated in promoting the non-homologous end joining (NHEJ) pathway to repair a subset of DNA double strand breaks (DSBs), but how ATM performs this function is still unclear. In this study, we identified that ATM phosphorylates the DNA-dependent protein kinase catalytic subunit (DNA-PK cs ), a core NHEJ factor, at its extreme C-terminus at threonine 4102 (T4102) in response to DSBs. Phosphorylation at T4102 stabilizes the interaction between DNA-PK cs and the Ku-DNA complex and promotes assembly and stabilization of the NHEJ machinery at DSBs. Ablating phosphorylation at this site results in decreased NHEJ, radiosensitivity, and increased radiation-induced genomic instability. Collectively, these findings establish a key role for ATM in NHEJ-dependent repair of DSBs through positive regulation of DNA-PK cs .
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12
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Zagelbaum J, Gautier J. Double-strand break repair and mis-repair in 3D. DNA Repair (Amst) 2023; 121:103430. [PMID: 36436496 PMCID: PMC10799305 DOI: 10.1016/j.dnarep.2022.103430] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 11/13/2022] [Accepted: 11/15/2022] [Indexed: 11/18/2022]
Abstract
DNA double-strand breaks (DSBs) are lesions that arise frequently from exposure to damaging agents as well as from ongoing physiological DNA transactions. Mis-repair of DSBs leads to rearrangements and structural variations in chromosomes, including insertions, deletions, and translocations implicated in disease. The DNA damage response (DDR) limits pathologic mutations and large-scale chromosome rearrangements. DSB repair initiates in 2D at DNA lesions with the stepwise recruitment of repair proteins and local chromatin remodeling which facilitates break accessibility. More complex structures are then formed via protein assembly into nanodomains and via genome folding into chromatin loops. Subsequently, 3D reorganization of DSBs is guided by clustering forces which drive the assembly of repair domains harboring multiple lesions. These domains are further stabilized and insulated into condensates via liquid-liquid phase-separation. Here, we discuss the benefits and risks associated with this 3D reorganization of the broken genome.
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Affiliation(s)
- Jennifer Zagelbaum
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA; Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Jean Gautier
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA; Department of Genetics and Development, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
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13
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Zagelbaum J, Schooley A, Zhao J, Schrank BR, Callen E, Zha S, Gottesman ME, Nussenzweig A, Rabadan R, Dekker J, Gautier J. Multiscale reorganization of the genome following DNA damage facilitates chromosome translocations via nuclear actin polymerization. Nat Struct Mol Biol 2023; 30:99-106. [PMID: 36564591 PMCID: PMC10104780 DOI: 10.1038/s41594-022-00893-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 11/04/2022] [Indexed: 12/24/2022]
Abstract
Nuclear actin-based movements have been shown to orchestrate clustering of DNA double-strand breaks (DSBs) into homology-directed repair domains. Here we describe multiscale three-dimensional genome reorganization following DNA damage and analyze the contribution of the nuclear WASP-ARP2/3-actin pathway toward chromatin topology alterations and pathologic repair. Hi-C analysis reveals genome-wide, DNA damage-induced chromatin compartment flips facilitated by ARP2/3 that enrich for open, A compartments. Damage promotes interactions between DSBs, which in turn facilitate aberrant, actin-dependent intra- and inter-chromosomal rearrangements. Our work establishes that clustering of resected DSBs into repair domains by nuclear actin assembly is coordinated with multiscale alterations in genome architecture that enable homology-directed repair while also increasing nonhomologous end-joining-dependent translocation frequency.
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Affiliation(s)
- Jennifer Zagelbaum
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Allana Schooley
- Department of Systems Biology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Junfei Zhao
- Department of Systems Biology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Benjamin R Schrank
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Elsa Callen
- Laboratory of Genome Integrity, National Institutes of Health, Bethesda, MD, USA
| | - Shan Zha
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Department of Pathology and Cell Biology and Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Max E Gottesman
- Department of Biochemistry and Biophysics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - André Nussenzweig
- Laboratory of Genome Integrity, National Institutes of Health, Bethesda, MD, USA
| | - Raul Rabadan
- Department of Systems Biology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Job Dekker
- Department of Systems Biology, University of Massachusetts Medical School, Worcester, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Jean Gautier
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
- Herbert Irving Comprehensive Cancer Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
- Department of Genetics and Development, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
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14
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Cisneros-Aguirre M, Ping X, Stark JM. To indel or not to indel: Factors influencing mutagenesis during chromosomal break end joining. DNA Repair (Amst) 2022; 118:103380. [PMID: 35926296 PMCID: PMC10105512 DOI: 10.1016/j.dnarep.2022.103380] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 07/22/2022] [Accepted: 07/24/2022] [Indexed: 12/16/2022]
Abstract
Chromosomal DNA double-strand breaks (DSBs) are the effective lesion of radiotherapy and other clastogenic cancer therapeutics, and are also the initiating event of many approaches to gene editing. Ligation of the DSBs by end joining (EJ) pathways can restore the broken chromosome, but the repair junctions can have insertion/deletion (indel) mutations. The indel patterns resulting from DSB EJ are likely defined by the initial structure of the DNA ends, how the ends are processed and synapsed prior to ligation, and the factors that mediate the ligation step. In this review, we describe key factors that influence these steps of DSB EJ in mammalian cells, which is significant both for understanding mutagenesis resulting from clastogenic cancer therapeutics, and for developing approaches to manipulating gene editing outcomes.
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Affiliation(s)
- Metztli Cisneros-Aguirre
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA; Irell and Manella Graduate School of Biological Sciences, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
| | - Xiaoli Ping
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
| | - Jeremy M Stark
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA; Irell and Manella Graduate School of Biological Sciences, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA.
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15
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Abdulla AZ, Vaillant C, Jost D. Painters in chromatin: a unified quantitative framework to systematically characterize epigenome regulation and memory. Nucleic Acids Res 2022; 50:9083-9104. [PMID: 36018799 PMCID: PMC9458448 DOI: 10.1093/nar/gkac702] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 08/03/2022] [Indexed: 12/24/2022] Open
Abstract
In eukaryotes, many stable and heritable phenotypes arise from the same DNA sequence, owing to epigenetic regulatory mechanisms relying on the molecular cooperativity of 'reader-writer' enzymes. In this work, we focus on the fundamental, generic mechanisms behind the epigenome memory encoded by post-translational modifications of histone tails. Based on experimental knowledge, we introduce a unified modeling framework, the painter model, describing the mechanistic interplay between sequence-specific recruitment of chromatin regulators, chromatin-state-specific reader-writer processes and long-range spreading mechanisms. A systematic analysis of the model building blocks highlights the crucial impact of tridimensional chromatin organization and state-specific recruitment of enzymes on the stability of epigenomic domains and on gene expression. In particular, we show that enhanced 3D compaction of the genome and enzyme limitation facilitate the formation of ultra-stable, confined chromatin domains. The model also captures how chromatin state dynamics impact the intrinsic transcriptional properties of the region, slower kinetics leading to noisier expression. We finally apply our framework to analyze experimental data, from the propagation of γH2AX around DNA breaks in human cells to the maintenance of heterochromatin in fission yeast, illustrating how the painter model can be used to extract quantitative information on epigenomic molecular processes.
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Affiliation(s)
- Amith Z Abdulla
- Laboratoire de Biologie et Modélisation de la Cellule, École Normale Supérieure de Lyon, CNRS, UMR5239, Inserm U1293, Université Claude Bernard Lyon 1, 46 Allée d’Italie, 69007 Lyon, France,École Normale Supérieure de Lyon, CNRS, Laboratoire de Physique, 46 Allée d’Italie, 69007 Lyon, France
| | - Cédric Vaillant
- Correspondence may also be addressed to Cédric Vaillant. Tel: +33 4 72 72 81 54; Fax: +33 4 72 72 80 00;
| | - Daniel Jost
- To whom correspondence should be addressed. Tel: +33 4 72 72 86 30; Fax: +33 4 72 72 80 00;
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16
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DNA Damage Response Regulation by Histone Ubiquitination. Int J Mol Sci 2022; 23:ijms23158187. [PMID: 35897775 PMCID: PMC9332593 DOI: 10.3390/ijms23158187] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 07/19/2022] [Accepted: 07/22/2022] [Indexed: 11/30/2022] Open
Abstract
Cells are constantly exposed to numerous genotoxic stresses that induce DNA damage. DNA double-strand breaks (DSBs) are among the most serious damages and should be systematically repaired to preserve genomic integrity. The efficiency of repair is closely associated with chromatin structure, which is regulated by posttranslational modifications of histones, including ubiquitination. Recent evidence shows crosstalk between histone ubiquitination and DNA damage responses, suggesting an integrated model for the systematic regulation of DNA repair. There are two major pathways for DSB repair, viz., nonhomologous end joining and homologous recombination, and the choice of the pathway is partially controlled by posttranslational modifications of histones, including ubiquitination. Histone ubiquitination changes chromatin structure in the vicinity of DSBs and serves as a platform to select and recruit repair proteins; the removal of these modifications by deubiquitinating enzymes suppresses the recruitment of repair proteins and promotes the convergence of repair reactions. This article provides a comprehensive overview of the DNA damage response regulated by histone ubiquitination in response to DSBs.
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17
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A POLD3/BLM dependent pathway handles DSBs in transcribed chromatin upon excessive RNA:DNA hybrid accumulation. Nat Commun 2022; 13:2012. [PMID: 35440629 PMCID: PMC9019021 DOI: 10.1038/s41467-022-29629-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 03/25/2022] [Indexed: 12/03/2022] Open
Abstract
Transcriptionally active loci are particularly prone to breakage and mounting evidence suggests that DNA Double-Strand Breaks arising in active genes are handled by a dedicated repair pathway, Transcription-Coupled DSB Repair (TC-DSBR), that entails R-loop accumulation and dissolution. Here, we uncover a function for the Bloom RecQ DNA helicase (BLM) in TC-DSBR in human cells. BLM is recruited in a transcription dependent-manner at DSBs where it fosters resection, RAD51 binding and accurate Homologous Recombination repair. However, in an R-loop dissolution-deficient background, we find that BLM promotes cell death. We report that upon excessive RNA:DNA hybrid accumulation, DNA synthesis is enhanced at DSBs, in a manner that depends on BLM and POLD3. Altogether our work unveils a role for BLM at DSBs in active chromatin, and highlights the toxic potential of RNA:DNA hybrids that accumulate at transcription-associated DSBs. DNA Double Strand breaks in transcriptionally active loci (TC-DSBs) undergo a dedicated repair pathway. Here, the authors show that excessive RNA:DNA hybrid accumulation at TC-DSBs elicits POLD3/BLM-dependent DNA synthesis that induces cell toxicity.
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18
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Kieffer SR, Lowndes NF. Immediate-Early, Early, and Late Responses to DNA Double Stranded Breaks. Front Genet 2022; 13:793884. [PMID: 35173769 PMCID: PMC8841529 DOI: 10.3389/fgene.2022.793884] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 01/10/2022] [Indexed: 12/18/2022] Open
Abstract
Loss or rearrangement of genetic information can result from incorrect responses to DNA double strand breaks (DSBs). The cellular responses to DSBs encompass a range of highly coordinated events designed to detect and respond appropriately to the damage, thereby preserving genomic integrity. In analogy with events occurring during viral infection, we appropriate the terms Immediate-Early, Early, and Late to describe the pre-repair responses to DSBs. A distinguishing feature of the Immediate-Early response is that the large protein condensates that form during the Early and Late response and are resolved upon repair, termed foci, are not visible. The Immediate-Early response encompasses initial lesion sensing, involving poly (ADP-ribose) polymerases (PARPs), KU70/80, and MRN, as well as rapid repair by so-called ‘fast-kinetic’ canonical non-homologous end joining (cNHEJ). Initial binding of PARPs and the KU70/80 complex to breaks appears to be mutually exclusive at easily ligatable DSBs that are repaired efficiently by fast-kinetic cNHEJ; a process that is PARP-, ATM-, 53BP1-, Artemis-, and resection-independent. However, at more complex breaks requiring processing, the Immediate-Early response involving PARPs and the ensuing highly dynamic PARylation (polyADP ribosylation) of many substrates may aid recruitment of both KU70/80 and MRN to DSBs. Complex DSBs rely upon the Early response, largely defined by ATM-dependent focal recruitment of many signalling molecules into large condensates, and regulated by complex chromatin dynamics. Finally, the Late response integrates information from cell cycle phase, chromatin context, and type of DSB to determine appropriate pathway choice. Critical to pathway choice is the recruitment of p53 binding protein 1 (53BP1) and breast cancer associated 1 (BRCA1). However, additional factors recruited throughout the DSB response also impact upon pathway choice, although these remain to be fully characterised. The Late response somehow channels DSBs into the appropriate high-fidelity repair pathway, typically either ‘slow-kinetic’ cNHEJ or homologous recombination (HR). Loss of specific components of the DSB repair machinery results in cells utilising remaining factors to effect repair, but often at the cost of increased mutagenesis. Here we discuss the complex regulation of the Immediate-Early, Early, and Late responses to DSBs proceeding repair itself.
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19
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García Fernández F, Fabre E. The Dynamic Behavior of Chromatin in Response to DNA Double-Strand Breaks. Genes (Basel) 2022; 13:genes13020215. [PMID: 35205260 PMCID: PMC8872016 DOI: 10.3390/genes13020215] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 01/18/2022] [Accepted: 01/19/2022] [Indexed: 02/05/2023] Open
Abstract
The primary functions of the eukaryotic nucleus as a site for the storage, retrieval, and replication of information require a highly dynamic chromatin organization, which can be affected by the presence of DNA damage. In response to double-strand breaks (DSBs), the mobility of chromatin at the break site is severely affected and, to a lesser extent, that of other chromosomes. The how and why of such movement has been widely studied over the last two decades, leading to different mechanistic models and proposed potential roles underlying both local and global mobility. Here, we review the state of the knowledge on current issues affecting chromatin mobility upon DSBs, and highlight its role as a crucial step in the DNA damage response (DDR).
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Affiliation(s)
- Fabiola García Fernández
- Institut Curie, CNRS UMR3664, Sorbonne Université, F-75005 Paris, France
- Correspondence: (F.G.F.); (E.F.)
| | - Emmanuelle Fabre
- Génomes Biologie Cellulaire et Thérapeutiques, CNRS UMR7212, INSERM U944, Université de Paris, F-75010 Paris, France
- Correspondence: (F.G.F.); (E.F.)
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20
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Shift in G1-Checkpoint from ATM-Alone to a Cooperative ATM Plus ATR Regulation with Increasing Dose of Radiation. Cells 2021; 11:cells11010063. [PMID: 35011623 PMCID: PMC8750242 DOI: 10.3390/cells11010063] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 12/23/2021] [Accepted: 12/24/2021] [Indexed: 12/13/2022] Open
Abstract
The current view of the involvement of PI3-kinases in checkpoint responses after DNA damage is that ATM is the key regulator of G1-, S- or G2-phase checkpoints, that ATR is only partly involved in the regulation of S- and G2-phase checkpoints and that DNA-PKcs is not involved in checkpoint regulation. However, further analysis of the contributions of these kinases to checkpoint responses in cells exposed to ionizing radiation (IR) recently uncovered striking integrations and interplays among ATM, ATR and DNA-PKcs that adapt not only to the phase of the cell cycle in which cells are irradiated, but also to the load of DNA double-strand breaks (DSBs), presumably to optimize their processing. Specifically, we found that low IR doses in G2-phase cells activate a G2-checkpoint that is regulated by epistatically coupled ATM and ATR. Thus, inhibition of either kinase suppresses almost fully its activation. At high IR doses, the epistatic ATM/ATR coupling relaxes, yielding to a cooperative regulation. Thus, single-kinase inhibition suppresses partly, and only combined inhibition suppresses fully G2-checkpoint activation. Interestingly, DNA-PKcs integrates with ATM/ATR in G2-checkpoint control, but functions in its recovery in a dose-independent manner. Strikingly, irradiation during S-phase activates, independently of dose, an exclusively ATR-dependent G2 checkpoint. Here, ATM couples with DNA-PKcs to regulate checkpoint recovery. In the present work, we extend these studies and investigate organization and functions of these PI3-kinases in the activation of the G1 checkpoint in cells irradiated either in the G0 or G1 phase. We report that ATM is the sole regulator of the G1 checkpoint after exposure to low IR doses. At high IR doses, ATM remains dominant, but contributions from ATR also become detectable and are associated with limited ATM/ATR-dependent end resection at DSBs. Under these conditions, only combined ATM + ATR inhibition fully abrogates checkpoint and resection. Contributions of DNA-PKcs and CHK2 to the regulation of the G1 checkpoint are not obvious in these experiments and may be masked by the endpoint employed for checkpoint analysis and perturbations in normal progression through the cell cycle of cells exposed to DNA-PKcs inhibitors. The results broaden our understanding of organization throughout the cell cycle and adaptation with increasing IR dose of the ATM/ATR/DNA-PKcs module to regulate checkpoint responses. They emphasize notable similarities and distinct differences between G1-, G2- and S-phase checkpoint regulation that may guide DSB processing decisions.
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21
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Crewe M, Madabhushi R. Topoisomerase-Mediated DNA Damage in Neurological Disorders. Front Aging Neurosci 2021; 13:751742. [PMID: 34899270 PMCID: PMC8656403 DOI: 10.3389/fnagi.2021.751742] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 10/23/2021] [Indexed: 12/12/2022] Open
Abstract
The nervous system is vulnerable to genomic instability and mutations in DNA damage response factors lead to numerous developmental and progressive neurological disorders. Despite this, the sources and mechanisms of DNA damage that are most relevant to the development of neuronal dysfunction are poorly understood. The identification of primarily neurological abnormalities in patients with mutations in TDP1 and TDP2 suggest that topoisomerase-mediated DNA damage could be an important underlying source of neuronal dysfunction. Here we review the potential sources of topoisomerase-induced DNA damage in neurons, describe the cellular mechanisms that have evolved to repair such damage, and discuss the importance of these repair mechanisms for preventing neurological disorders.
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Affiliation(s)
| | - Ram Madabhushi
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
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22
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Mohan C, Das C, Tyler J. Histone and Chromatin Dynamics Facilitating DNA repair. DNA Repair (Amst) 2021; 107:103183. [PMID: 34419698 PMCID: PMC9733910 DOI: 10.1016/j.dnarep.2021.103183] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 12/13/2022]
Abstract
Our nuclear genomes are complexed with histone proteins to form nucleosomes, the repeating units of chromatin which function to package and limit unscheduled access to the genome. In response to helix-distorting DNA lesions and DNA double-strand breaks, chromatin is disassembled around the DNA lesion to facilitate DNA repair and it is reassembled after repair is complete to reestablish the epigenetic landscape and regulating access to the genome. DNA damage also triggers decondensation of the local chromatin structure, incorporation of histone variants and dramatic transient increases in chromatin mobility to facilitate the homology search during homologous recombination. Here we review the current state of knowledge of these changes in histone and chromatin dynamics in response to DNA damage, the molecular mechanisms mediating these dynamics, as well as their functional contributions to the maintenance of genome integrity to prevent human diseases including cancer.
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Affiliation(s)
- Chitra Mohan
- Department of Pathology and Laboratory Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Chandrima Das
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata, 700064, India
| | - Jessica Tyler
- Department of Pathology and Laboratory Medicine, 1300 York Avenue, New York, NY, 10065, USA.
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23
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Zentout S, Smith R, Jacquier M, Huet S. New Methodologies to Study DNA Repair Processes in Space and Time Within Living Cells. Front Cell Dev Biol 2021; 9:730998. [PMID: 34589495 PMCID: PMC8473836 DOI: 10.3389/fcell.2021.730998] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 08/25/2021] [Indexed: 01/02/2023] Open
Abstract
DNA repair requires a coordinated effort from an array of factors that play different roles in the DNA damage response from recognizing and signaling the presence of a break, creating a repair competent environment, and physically repairing the lesion. Due to the rapid nature of many of these events, live-cell microscopy has become an invaluable method to study this process. In this review we outline commonly used tools to induce DNA damage under the microscope and discuss spatio-temporal analysis tools that can bring added information regarding protein dynamics at sites of damage. In particular, we show how to go beyond the classical analysis of protein recruitment curves to be able to assess the dynamic association of the repair factors with the DNA lesions as well as the target-search strategies used to efficiently find these lesions. Finally, we discuss how the use of mathematical models, combined with experimental evidence, can be used to better interpret the complex dynamics of repair proteins at DNA lesions.
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Affiliation(s)
- Siham Zentout
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes)-UMR 6290, BIOSIT-UMS 3480, Rennes, France
| | - Rebecca Smith
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes)-UMR 6290, BIOSIT-UMS 3480, Rennes, France
| | - Marine Jacquier
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes)-UMR 6290, BIOSIT-UMS 3480, Rennes, France
| | - Sébastien Huet
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes)-UMR 6290, BIOSIT-UMS 3480, Rennes, France
- Institut Universitaire de France, Paris, France
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24
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Cellular functions of the protein kinase ATM and their relevance to human disease. Nat Rev Mol Cell Biol 2021; 22:796-814. [PMID: 34429537 DOI: 10.1038/s41580-021-00394-2] [Citation(s) in RCA: 110] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/18/2021] [Indexed: 02/07/2023]
Abstract
The protein kinase ataxia telangiectasia mutated (ATM) is a master regulator of double-strand DNA break (DSB) signalling and stress responses. For three decades, ATM has been investigated extensively to elucidate its roles in the DNA damage response (DDR) and in the pathogenesis of ataxia telangiectasia (A-T), a human neurodegenerative disease caused by loss of ATM. Although hundreds of proteins have been identified as ATM phosphorylation targets and many important roles for this kinase have been identified, it is still unclear how ATM deficiency leads to the early-onset cerebellar degeneration that is common in all individuals with A-T. Recent studies suggest the existence of links between ATM deficiency and other cerebellum-specific neurological disorders, as well as the existence of broader similarities with more common neurodegenerative disorders. In this Review, we discuss recent structural insights into ATM regulation, and possible aetiologies of A-T phenotypes, including reactive oxygen species, mitochondrial dysfunction, alterations in transcription, R-loop metabolism and alternative splicing, defects in cellular proteostasis and metabolism, and potential pathogenic roles for hyper-poly(ADP-ribosyl)ation.
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25
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Verma P, Greenberg RA. Communication between chromatin and homologous recombination. Curr Opin Genet Dev 2021; 71:1-9. [PMID: 34098484 DOI: 10.1016/j.gde.2021.05.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 05/13/2021] [Indexed: 12/24/2022]
Abstract
Higher-order chromatin packing serves as a structural barrier to the recognition and repair of genomic lesions. The initiation and outcome of the repair response is dictated by a highly coordinated yet complex interplay between chromatin modifying enzymes and their cognate readers, damage induced chemical modifications, nucleosome density, transcriptional state, and cell cycle-dependent availability of DNA repair machinery. The physical and chemical properties of the DNA lesions themselves further regulate the nature of ensuing chromatin responses. Here we review recent discoveries across these various contexts, where chromatin regulates the homology-guided double-strand break repair mechanism, homologous recombination, and also highlight the key knowledge gaps vital to generate a holistic understanding of this process and its contributions to genome integrity.
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Affiliation(s)
- Priyanka Verma
- Department of Cancer Biology, Penn Center for Genome Integrity, Basser Center for BRCA, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Roger A Greenberg
- Department of Cancer Biology, Penn Center for Genome Integrity, Basser Center for BRCA, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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26
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Mangeat T, Labouesse S, Allain M, Negash A, Martin E, Guénolé A, Poincloux R, Estibal C, Bouissou A, Cantaloube S, Vega E, Li T, Rouvière C, Allart S, Keller D, Debarnot V, Wang XB, Michaux G, Pinot M, Le Borgne R, Tournier S, Suzanne M, Idier J, Sentenac A. Super-resolved live-cell imaging using random illumination microscopy. CELL REPORTS METHODS 2021; 1:100009. [PMID: 35474693 PMCID: PMC9017237 DOI: 10.1016/j.crmeth.2021.100009] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/12/2021] [Accepted: 04/08/2021] [Indexed: 12/11/2022]
Abstract
Current super-resolution microscopy (SRM) methods suffer from an intrinsic complexity that might curtail their routine use in cell biology. We describe here random illumination microscopy (RIM) for live-cell imaging at super-resolutions matching that of 3D structured illumination microscopy, in a robust fashion. Based on speckled illumination and statistical image reconstruction, easy to implement and user-friendly, RIM is unaffected by optical aberrations on the excitation side, linear to brightness, and compatible with multicolor live-cell imaging over extended periods of time. We illustrate the potential of RIM on diverse biological applications, from the mobility of proliferating cell nuclear antigen (PCNA) in U2OS cells and kinetochore dynamics in mitotic S. pombe cells to the 3D motion of myosin minifilaments deep inside Drosophila tissues. RIM's inherent simplicity and extended biological applicability, particularly for imaging at increased depths, could help make SRM accessible to biology laboratories.
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Affiliation(s)
- Thomas Mangeat
- LITC Core Facility, Centre de Biologie Integrative, Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Simon Labouesse
- Institut Fresnel, Aix Marseille Université, CNRS, Centrale Marseille, Marseille, France
| | - Marc Allain
- Institut Fresnel, Aix Marseille Université, CNRS, Centrale Marseille, Marseille, France
| | - Awoke Negash
- Institut Fresnel, Aix Marseille Université, CNRS, Centrale Marseille, Marseille, France
| | - Emmanuel Martin
- Molecular, Cellular & Developmental Biology (MCD), Center of Integrative Biology (CBI), Toulouse University, CNRS, UPS, Toulouse, France
| | - Aude Guénolé
- Molecular, Cellular & Developmental Biology (MCD), Center of Integrative Biology (CBI), Toulouse University, CNRS, UPS, Toulouse, France
| | - Renaud Poincloux
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Claire Estibal
- LITC Core Facility, Centre de Biologie Integrative, Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Anaïs Bouissou
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Sylvain Cantaloube
- LITC Core Facility, Centre de Biologie Integrative, Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Elodie Vega
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Tong Li
- Molecular, Cellular & Developmental Biology (MCD), Center of Integrative Biology (CBI), Toulouse University, CNRS, UPS, Toulouse, France
| | - Christian Rouvière
- LITC Core Facility, Centre de Biologie Integrative, Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Sophie Allart
- INSERM Université de Toulouse, UPS, CNRS, Centre de Physiopathologie de Toulouse Purpan (CPTP), Toulouse, France
| | - Debora Keller
- Molecular, Cellular & Developmental Biology (MCD), Center of Integrative Biology (CBI), Toulouse University, CNRS, UPS, Toulouse, France
| | - Valentin Debarnot
- LITC Core Facility, Centre de Biologie Integrative, Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Xia Bo Wang
- Molecular, Cellular & Developmental Biology (MCD), Center of Integrative Biology (CBI), Toulouse University, CNRS, UPS, Toulouse, France
| | - Grégoire Michaux
- Univ Rennes, CNRS, Institut de Génétique et Développement de Rennes (IGDR) - UMR 6290, 35000 Rennes, France
| | - Mathieu Pinot
- Univ Rennes, CNRS, Institut de Génétique et Développement de Rennes (IGDR) - UMR 6290, 35000 Rennes, France
| | - Roland Le Borgne
- Univ Rennes, CNRS, Institut de Génétique et Développement de Rennes (IGDR) - UMR 6290, 35000 Rennes, France
| | - Sylvie Tournier
- Molecular, Cellular & Developmental Biology (MCD), Center of Integrative Biology (CBI), Toulouse University, CNRS, UPS, Toulouse, France
| | - Magali Suzanne
- Molecular, Cellular & Developmental Biology (MCD), Center of Integrative Biology (CBI), Toulouse University, CNRS, UPS, Toulouse, France
| | - Jérome Idier
- LS2N, CNRS UMR 6004, 1 rue de la Noë, F44321 Nantes Cedex 3, France
| | - Anne Sentenac
- Institut Fresnel, Aix Marseille Université, CNRS, Centrale Marseille, Marseille, France
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27
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Lesage E, Clouaire T, Legube G. Repair of DNA double-strand breaks in RNAPI- and RNAPII-transcribed loci. DNA Repair (Amst) 2021; 104:103139. [PMID: 34111758 DOI: 10.1016/j.dnarep.2021.103139] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 05/18/2021] [Accepted: 05/18/2021] [Indexed: 12/15/2022]
Abstract
DNA double-strand breaks (DSBs) are toxic lesions triggered not only by environmental sources, but also by a large number of physiological processes. Of importance, endogenous DSBs frequently occur in genomic loci that are transcriptionally active. Recent work suggests that DSBs occurring in transcribed loci are handled by specific pathway(s) that entail local transcriptional repression, chromatin signaling, the involvement of RNA species and DSB mobility. In this Graphical Review we provide an updated view of the "Transcription-Coupled DSB Repair" (TC-DSBR) pathway(s) that are mounted at DSBs occurring in loci transcribed by RNA Polymerase I (RNAPI) or RNA Polymerase II (RNAPII), highlighting differences and common features, as well as yet unanswered questions.
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Affiliation(s)
- E Lesage
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), UPS, CNRS, Toulouse, France
| | - T Clouaire
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), UPS, CNRS, Toulouse, France
| | - G Legube
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), UPS, CNRS, Toulouse, France.
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28
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Zou RS, Liu Y, Wu B, Ha T. Cas9 deactivation with photocleavable guide RNAs. Mol Cell 2021; 81:1553-1565.e8. [PMID: 33662274 PMCID: PMC8026597 DOI: 10.1016/j.molcel.2021.02.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 12/23/2020] [Accepted: 02/02/2021] [Indexed: 12/11/2022]
Abstract
Precise control of CRISPR-Cas9 would improve its safety and applicability. Controlled CRISPR inhibition is a promising approach but is complicated by separate inhibitor delivery, incomplete deactivation, and slow kinetics. To overcome these obstacles, we engineered photocleavable guide RNAs (pcRNAs) that endow Cas9 nucleases and base editors with a built-in mechanism for light-based deactivation. pcRNA enabled the fastest (<1 min) and most complete (<1% residual indels) approach for Cas9 deactivation. It also exhibited significantly enhanced specificity with wild-type Cas9. Time-resolved deactivation revealed that 12-36 h of Cas9 activity or 2-4 h of base editor activity was sufficient to achieve high editing efficiency. pcRNA is useful for studies of the cellular response to DNA damage by abolishing sustained cycles of damage and repair that would otherwise desynchronize response trajectories. Together, pcRNA expands the CRISPR toolbox for precision genome editing and studies of DNA damage and repair.
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Affiliation(s)
- Roger S Zou
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Yang Liu
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Bin Wu
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Taekjip Ha
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Biophysics and Biophysical Chemistry, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Biophysics, Johns Hopkins University, Baltimore, MD 21205, USA; Howard Hughes Medical Institute, Baltimore, MD 21205, USA.
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29
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Cabrini M, Roncador M, Galbiati A, Cipolla L, Maffia A, Iannelli F, Sabbioneda S, d'Adda di Fagagna F, Francia S. DROSHA is recruited to DNA damage sites by the MRN complex to promote non-homologous end joining. J Cell Sci 2021; 134:jcs.249706. [PMID: 33558311 PMCID: PMC8015226 DOI: 10.1242/jcs.249706] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 01/23/2021] [Indexed: 11/20/2022] Open
Abstract
The DNA damage response (DDR) is the signaling cascade that recognizes DNA double-strand breaks (DSBs) and promotes their resolution via the DNA repair pathways of non-homologous end joining (NHEJ) or homologous recombination (HR). We and others have shown that DDR activation requires DROSHA; however, whether DROSHA exerts its functions by associating with damage sites, what controls its recruitment, and how DROSHA influences DNA repair remains poorly understood. Here, we show that DROSHA associates with DSBs independently of transcription. Neither H2AX, nor ATM or DNA-PK kinase activities are required for recruitment of DROSHA to break sites. Rather, DROSHA interacts with RAD50, and inhibition of the MRN complex by mirin treatment abolishes this interaction. MRN complex inactivation by RAD50 knockdown or mirin treatment prevents DROSHA recruitment to DSBs and, as a consequence, also prevents 53BP1 (also known as TP53BP1) recruitment. During DNA repair, DROSHA inactivation reduces NHEJ and boosts HR frequency. Indeed, DROSHA knockdown also increases the association of downstream HR factors such as RAD51 to DNA ends. Overall, our results demonstrate that DROSHA is recruited at DSBs by the MRN complex and directs DNA repair towards NHEJ.
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Affiliation(s)
- Matteo Cabrini
- Istituto di Genetica Molecolare, CNR - Consiglio Nazionale delle Ricerche, Pavia 27100, Italy.,IFOM Foundation - The FIRC Institute of Molecular Oncology Foundation, Milan 20139, Italy
| | - Marco Roncador
- Istituto di Genetica Molecolare, CNR - Consiglio Nazionale delle Ricerche, Pavia 27100, Italy
| | - Alessandro Galbiati
- IFOM Foundation - The FIRC Institute of Molecular Oncology Foundation, Milan 20139, Italy
| | - Lina Cipolla
- Istituto di Genetica Molecolare, CNR - Consiglio Nazionale delle Ricerche, Pavia 27100, Italy
| | - Antonio Maffia
- Istituto di Genetica Molecolare, CNR - Consiglio Nazionale delle Ricerche, Pavia 27100, Italy
| | - Fabio Iannelli
- IFOM Foundation - The FIRC Institute of Molecular Oncology Foundation, Milan 20139, Italy
| | - Simone Sabbioneda
- Istituto di Genetica Molecolare, CNR - Consiglio Nazionale delle Ricerche, Pavia 27100, Italy
| | - Fabrizio d'Adda di Fagagna
- Istituto di Genetica Molecolare, CNR - Consiglio Nazionale delle Ricerche, Pavia 27100, Italy .,IFOM Foundation - The FIRC Institute of Molecular Oncology Foundation, Milan 20139, Italy
| | - Sofia Francia
- Istituto di Genetica Molecolare, CNR - Consiglio Nazionale delle Ricerche, Pavia 27100, Italy .,IFOM Foundation - The FIRC Institute of Molecular Oncology Foundation, Milan 20139, Italy
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30
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Arnould C, Rocher V, Finoux AL, Clouaire T, Li K, Zhou F, Caron P, Mangeot PE, Ricci EP, Mourad R, Haber JE, Noordermeer D, Legube G. Loop extrusion as a mechanism for formation of DNA damage repair foci. Nature 2021; 590:660-665. [PMID: 33597753 PMCID: PMC7116834 DOI: 10.1038/s41586-021-03193-z] [Citation(s) in RCA: 154] [Impact Index Per Article: 51.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 01/06/2021] [Indexed: 12/26/2022]
Abstract
The repair of DNA double-strand breaks (DSBs) is essential for safeguarding genome integrity. When a DSB forms, the PI3K-related ATM kinase rapidly triggers the establishment of megabase-sized, chromatin domains decorated with phosphorylated histone H2AX (γH2AX), which act as seeds for the formation of DNA-damage response foci1. It is unclear how these foci are rapidly assembled to establish a 'repair-prone' environment within the nucleus. Topologically associating domains are a key feature of 3D genome organization that compartmentalize transcription and replication, but little is known about their contribution to DNA repair processes2,3. Here we show that topologically associating domains are functional units of the DNA damage response, and are instrumental for the correct establishment of γH2AX-53BP1 chromatin domains in a manner that involves one-sided cohesin-mediated loop extrusion on both sides of the DSB. We propose a model in which H2AX-containing nucleosomes are rapidly phosphorylated as they actively pass by DSB-anchored cohesin. Our work highlights the importance of chromosome conformation in the maintenance of genome integrity and demonstrates the establishment of a chromatin modification by loop extrusion.
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Affiliation(s)
- Coline Arnould
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), UPS, CNRS, Toulouse, France
| | - Vincent Rocher
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), UPS, CNRS, Toulouse, France
| | - Anne-Laure Finoux
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), UPS, CNRS, Toulouse, France
| | - Thomas Clouaire
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), UPS, CNRS, Toulouse, France
| | - Kevin Li
- Rosenstiel Basic Medical Sciences Research Center and Department of Biology, Brandeis University, Waltham, MA, USA
| | - Felix Zhou
- Rosenstiel Basic Medical Sciences Research Center and Department of Biology, Brandeis University, Waltham, MA, USA
| | - Pierre Caron
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), UPS, CNRS, Toulouse, France
| | - Philippe E Mangeot
- CIRI - International Center for Infectiology Research, Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, University of Lyon, Lyon, France
| | - Emiliano P Ricci
- Laboratoire de Biologie et Modélisation de la Cellule, Université de Lyon, INSERM U1293, CNRS UMR 5239, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Raphaël Mourad
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), UPS, CNRS, Toulouse, France
| | - James E Haber
- Rosenstiel Basic Medical Sciences Research Center and Department of Biology, Brandeis University, Waltham, MA, USA
| | - Daan Noordermeer
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Gaëlle Legube
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), UPS, CNRS, Toulouse, France.
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31
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de Polo A, Labbé DP. Diet-Dependent Metabolic Regulation of DNA Double-Strand Break Repair in Cancer: More Choices on the Menu. Cancer Prev Res (Phila) 2021; 14:403-414. [PMID: 33509805 DOI: 10.1158/1940-6207.capr-20-0470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/27/2020] [Accepted: 01/21/2021] [Indexed: 11/16/2022]
Abstract
Despite several epidemiologic and preclinical studies supporting the role of diet in cancer progression, the complexity of the diet-cancer link makes it challenging to deconvolute the underlying mechanisms, which remain scantly elucidated. This review focuses on genomic instability as one of the cancer hallmarks affected by diet-dependent metabolic alterations. We discuss how altered dietary intake of metabolites of the one-carbon metabolism, including methionine, folate, and vitamins B and C, can impact the methylation processes and thereby tumorigenesis. We present the concept that the protumorigenic effect of certain diets, such as the Western diet, is in part due to a diet-induced erosion of the DNA repair capacity caused by altered epigenetic and epitranscriptomic landscapes, while the protective effect of other dietary patterns, such as the Mediterranean diet, can be partly explained by their ability to sustain a proficient DNA repair. In particular, considering that diet-dependent alterations of the one-carbon metabolism can impact the rate of methylation processes, changes in dietary patterns can affect the activity of writers and erasers of histone and RNA methyl marks and consequently impair their role in ensuring a proficient DNA damage repair.
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Affiliation(s)
- Anna de Polo
- Division of Urology, Department of Surgery, McGill University and Cancer Research Program, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - David P Labbé
- Division of Urology, Department of Surgery, McGill University and Cancer Research Program, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.
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32
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Zou RS, Ha T. Light activation and deactivation of Cas9 for DNA repair studies. Methods Enzymol 2021; 661:219-249. [PMID: 34776214 DOI: 10.1016/bs.mie.2021.08.007] [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] [Indexed: 01/04/2023]
Abstract
DNA double-strand breaks in DNA (DSBs) are common yet highly detrimental events in living organisms. To repair the damage, each cell requires a coordinated set of DNA damage response (DDR) proteins that can respond quickly, effectively, and precisely. Better understanding of these processes is therefore essential and would require an effective means of inducing targeted DSBs on demand, but previous methods are hampered by limited control over genomic location, timing, or lesion types. Tight spatiotemporal control of CRISPR-Cas9 activity has potential to overcome these limitations, which led to the development of two methods for rapid activation or deactivation of Cas9 using light. In this chapter, we discuss how control of Cas9 can advance DDR studies, describe protocols to control Cas9 activation and deactivation using this new technology, and finally outline three compatible readouts of DNA damage and the cellular response: DSB levels using droplet digital PCR, repair factor localization using ChIP-seq, and insertion-deletion (indel) repair outcomes using Sanger sequencing.
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Affiliation(s)
- Roger S Zou
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MA, United States
| | - Taekjip Ha
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MA, United States; Department of Biophysics and Biophysical Chemistry, Johns Hopkins University, Baltimore, MA, United States; Department of Biophysics, Johns Hopkins University, Baltimore, MA, United States; Howard Hughes Medical Institute, Baltimore, MA, United States.
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33
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Owiti NA, Nagel ZD, Engelward BP. Fluorescence Sheds Light on DNA Damage, DNA Repair, and Mutations. Trends Cancer 2020; 7:240-248. [PMID: 33203608 DOI: 10.1016/j.trecan.2020.10.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 10/09/2020] [Accepted: 10/15/2020] [Indexed: 12/17/2022]
Abstract
DNA damage can lead to carcinogenic mutations and toxicity that promotes diseases. Therefore, having rapid assays to quantify DNA damage, DNA repair, mutations, and cytotoxicity is broadly relevant to health. For example, DNA damage assays can be used to screen chemicals for genotoxicity, and knowledge about DNA repair capacity has applications in precision prevention and in personalized medicine. Furthermore, knowledge of mutation frequency has predictive power for downstream cancer, and assays for cytotoxicity can predict deleterious health effects. Tests for all of these purposes have been rendered faster and more effective via adoption of fluorescent readouts. Here, we provide an overview of established and emerging cell-based assays that exploit fluorescence for studies of DNA damage and its consequences.
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Affiliation(s)
- Norah A Owiti
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Zachary D Nagel
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Bevin P Engelward
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
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34
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Ning S, Wang L. The Multifunctional Protein p62 and Its Mechanistic Roles in Cancers. Curr Cancer Drug Targets 2020; 19:468-478. [PMID: 30332964 PMCID: PMC8052633 DOI: 10.2174/1568009618666181016164920] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 08/17/2018] [Accepted: 09/28/2018] [Indexed: 12/16/2022]
Abstract
The multifunctional signaling hub p62 is well recognized as a ubiquitin sensor and a selective autophagy receptor. As a ubiquitin sensor, p62 promotes NFκB activation by facilitating TRAF6 ubiquitination and aggregation. As a selective autophagy receptor, p62 sorts ubiquitinated substrates including p62 itself for lysosome-mediated degradation. p62 plays crucial roles in myriad cellular processes including DNA damage response, aging/senescence, infection and immunity, chronic inflammation, and cancerogenesis, dependent on or independent of autophagy. Targeting p62-mediated autophagy may represent a promising strategy for clinical interventions of different cancers. In this review, we summarize the transcriptional and post-translational regulation of p62, and its mechanistic roles in cancers, with the emphasis on its roles in regulation of DNA damage response and its connection to the cGAS-STING-mediated antitumor immune response, which is promising for cancer vaccine design.
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Affiliation(s)
- Shunbin Ning
- Division of Infectious Diseases, Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, United States.,Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, United States
| | - Ling Wang
- Division of Infectious Diseases, Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, United States.,Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, United States
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35
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Miné-Hattab J, Chiolo I. Complex Chromatin Motions for DNA Repair. Front Genet 2020; 11:800. [PMID: 33061931 PMCID: PMC7481375 DOI: 10.3389/fgene.2020.00800] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 07/06/2020] [Indexed: 12/26/2022] Open
Abstract
A number of studies across different model systems revealed that chromatin undergoes significant changes in dynamics in response to DNA damage. These include local motion changes at damage sites, increased nuclear exploration of both damaged and undamaged loci, and directed motions to new nuclear locations associated with certain repair pathways. These studies also revealed the need for new analytical methods to identify directed motions in a context of mixed trajectories, and the importance of investigating nuclear dynamics over different time scales to identify diffusion regimes. Here we provide an overview of the current understanding of this field, including imaging and analytical methods developed to investigate nuclear dynamics in different contexts. These dynamics are essential for genome integrity. Identifying the molecular mechanisms responsible for these movements is key to understanding how their misregulation contributes to cancer and other genome instability disorders.
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Affiliation(s)
- Judith Miné-Hattab
- UMR 3664, CNRS, Institut Curie, PSL Research University, Paris, France
- UMR 3664, CNRS, Institut Curie, Sorbonne Université, Paris, France
| | - Irene Chiolo
- Molecular and Computational Biology Department, University of Southern California, Los Angeles, CA, United States
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36
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Luo R, Song J, Xiao X, Xie Z, Zhao Z, Zhang W, Miao S, Tang Y, Ran L. Identifying CpG methylation signature as a promising biomarker for recurrence and immunotherapy in non-small-cell lung carcinoma. Aging (Albany NY) 2020; 12:14649-14676. [PMID: 32723974 PMCID: PMC7425482 DOI: 10.18632/aging.103517] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 06/04/2020] [Indexed: 12/15/2022]
Abstract
Epigenetic alterations are crucial to oncogenesis and regulation of gene expression in non-small-cell lung carcinoma (NSCLC). DNA methylation (DNAm) biomarkers may provide molecular-level prediction of relapse risk in cancer. Identification of optimal treatment is warranted for improving clinical management of NSCLC patients. Using machine learning algorithm we identified 4 recurrence predictive CpG methylation markers (cg00253681/ART4, cg00111503/KCNK9, cg02715629/FAM83A, cg03282991/C6orf10) and constructed a risk score model that potently predicted recurrence-free survival and prognosis for patients with NSCLC (P = 0.0002). Integrating genomic, transcriptomic, proteomic and clinical data, the DNAm-based risk score was observed to significantly associate with clinical stage, cell proliferation markers, somatic alterations, tumor mutation burden (TMB) as well as DNA damage response (DDR) genes, and potentially predict the efficacy of immunotherapy. In general, our identified DNAm signature shows a significant correlation to TMB and DDR pathways, and serves as an effective biomarker for predicting NSCLC recurrence and response to immunotherapy. These findings demonstrate the utility of 4-DNAm-marker panel in the prognosis, treatment decision-making and evaluation of therapeutic responses for NSCLC.
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Affiliation(s)
- Ruihan Luo
- Department of Bioinformatics, The Basic Medical School of Chongqing Medical University, Chongqing, China
| | - Jing Song
- Department of Bioinformatics, The Basic Medical School of Chongqing Medical University, Chongqing, China
| | - Xiao Xiao
- Department of Endocrine and Breast Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhengbo Xie
- Information Center Department, Chongqing Medical University, Chongqing, China
| | - Zhiyuan Zhao
- Information Center Department, Chongqing Medical University, Chongqing, China
| | - Wanfeng Zhang
- Department of Bioinformatics, The Basic Medical School of Chongqing Medical University, Chongqing, China
| | - Shiqi Miao
- Department of Bioinformatics, The Basic Medical School of Chongqing Medical University, Chongqing, China
| | - Yongyao Tang
- Molecular and Tumor Research Center, Chongqing Medical University, Chongqing, China
| | - Longke Ran
- Department of Bioinformatics, The Basic Medical School of Chongqing Medical University, Chongqing, China
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37
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DNA double-strand breaks induce H2Ax phosphorylation domains in a contact-dependent manner. Nat Commun 2020; 11:3158. [PMID: 32572033 PMCID: PMC7308414 DOI: 10.1038/s41467-020-16926-x] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 05/29/2020] [Indexed: 01/20/2023] Open
Abstract
Efficient repair of DNA double-strand breaks (DSBs) requires a coordinated DNA Damage Response (DDR), which includes phosphorylation of histone H2Ax, forming γH2Ax. This histone modification spreads beyond the DSB into neighboring chromatin, generating a DDR platform that protects against end disassociation and degradation, minimizing chromosomal rearrangements. However, mechanisms that determine the breadth and intensity of γH2Ax domains remain unclear. Here, we show that chromosomal contacts of a DSB site are the primary determinants for γH2Ax landscapes. DSBs that disrupt a topological border permit extension of γH2Ax domains into both adjacent compartments. In contrast, DSBs near a border produce highly asymmetric DDR platforms, with γH2Ax nearly absent from one broken end. Collectively, our findings lend insights into a basic DNA repair mechanism and how the precise location of a DSB may influence genome integrity. Formation of γH2Ax serves as a checkpoint for double-strand break (DSB) repair pathways. Here the authors reveal via integrated chromatin analysis that γH2Ax domains are established by chromosomal contacts with the DSB site.
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Abstract
Cells confront DNA damage in every cell cycle. Among the most deleterious types of DNA damage are DNA double-strand breaks (DSBs), which can cause cell lethality if unrepaired or cancers if improperly repaired. In response to DNA DSBs, cells activate a complex DNA damage checkpoint (DDC) response that arrests the cell cycle, reprograms gene expression, and mobilizes DNA repair factors to prevent the inheritance of unrepaired and broken chromosomes. Here we examine the DDC, induced by DNA DSBs, in the budding yeast model system and in mammals.
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Affiliation(s)
- David P Waterman
- Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, Massachusetts 02454, USA;
| | - James E Haber
- Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, Massachusetts 02454, USA;
| | - Marcus B Smolka
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York 14853, USA;
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Akagawa R, Trinh HT, Saha LK, Tsuda M, Hirota K, Yamada S, Shibata A, Kanemaki MT, Nakada S, Takeda S, Sasanuma H. UBC13-Mediated Ubiquitin Signaling Promotes Removal of Blocking Adducts from DNA Double-Strand Breaks. iScience 2020; 23:101027. [PMID: 32283528 PMCID: PMC7155233 DOI: 10.1016/j.isci.2020.101027] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 02/22/2020] [Accepted: 03/26/2020] [Indexed: 12/25/2022] Open
Abstract
Chemical modifications and adducts at DNA double-strand break (DSB) ends must be cleaned before re-joining by non-homologous end-joining (NHEJ). MRE11 nuclease is essential for efficient removal of Topoisomerase II (TOP2)-DNA adducts from TOP2 poison-induced DSBs. However, mechanisms in MRE11 recruitment to DSB sites in G1 phase remain poorly understood. Here, we report that TOP2-DNA adducts are expeditiously removed through UBC13-mediated polyubiquitination, which promotes DSB resection in G2 phase. We found that this ubiquitin signaling is required for efficient recruitment of MRE11 onto DSB sites in G1 by facilitating localization of RAP80 and BRCA1 to DSB sites and complex formation between BRCA1 and MRE11 at DSB sites. UBC13 and MRE11 are dispensable for restriction-enzyme-induced "clean" DSBs repair but responsible for over 50% and 70% of NHEJ-dependent repair of γ-ray-induced "dirty" DSBs, respectively. In conclusion, ubiquitin signaling promotes nucleolytic removal of DSB blocking adducts by MRE11 before NHEJ.
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Affiliation(s)
- Remi Akagawa
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Hai Thanh Trinh
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Liton Kumar Saha
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Masataka Tsuda
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kouji Hirota
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Hachioji-shi, Tokyo 192-0397, Japan
| | - Shintaro Yamada
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501, Japan; Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Atsushi Shibata
- Signal Transduction Program, Gunma University Initiative for Advanced Research (GIAR), Gunma University, Maebashi, Gunma 371-8511, Japan
| | - Masato T Kanemaki
- National Institute of Genetics, Research Organization of Information and Systems (ROIS), and Department of Genetics, The Graduate University for Advanced Studies (SOKENDAI), Yata 1111, Mishima, Shizuoka 411-8540, Japan
| | - Shinichiro Nakada
- Department of Bioregulation and Cellular Response, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Shunichi Takeda
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501, Japan.
| | - Hiroyuki Sasanuma
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501, Japan.
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40
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Vítor AC, Huertas P, Legube G, de Almeida SF. Studying DNA Double-Strand Break Repair: An Ever-Growing Toolbox. Front Mol Biosci 2020; 7:24. [PMID: 32154266 PMCID: PMC7047327 DOI: 10.3389/fmolb.2020.00024] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 02/04/2020] [Indexed: 12/29/2022] Open
Abstract
To ward off against the catastrophic consequences of persistent DNA double-strand breaks (DSBs), eukaryotic cells have developed a set of complex signaling networks that detect these DNA lesions, orchestrate cell cycle checkpoints and ultimately lead to their repair. Collectively, these signaling networks comprise the DNA damage response (DDR). The current knowledge of the molecular determinants and mechanistic details of the DDR owes greatly to the continuous development of ground-breaking experimental tools that couple the controlled induction of DSBs at distinct genomic positions with assays and reporters to investigate DNA repair pathways, their impact on other DNA-templated processes and the specific contribution of the chromatin environment. In this review, we present these tools, discuss their pros and cons and illustrate their contribution to our current understanding of the DDR.
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Affiliation(s)
- Alexandra C Vítor
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
| | - Pablo Huertas
- Department of Genetics, University of Seville, Seville, Spain.,Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Seville, Spain
| | - Gaëlle Legube
- LBCMCP, Centre de Biologie Integrative (CBI), CNRS, Université de Toulouse, Toulouse, France
| | - Sérgio F de Almeida
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
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NF1 patient missense variants predict a role for ATM in modifying neurofibroma initiation. Acta Neuropathol 2020; 139:157-174. [PMID: 31664505 DOI: 10.1007/s00401-019-02086-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 10/11/2019] [Accepted: 10/15/2019] [Indexed: 01/01/2023]
Abstract
In Neurofibromatosis type 1, NF1 gene mutations in Schwann cells (SC) drive benign plexiform neurofibroma (PNF), and no additional SC changes explain patient-to-patient variability in tumor number. Evidence from twin studies suggests that variable expressivity might be caused by unidentified modifier genes. Whole exome sequencing of SC and fibroblast DNA from the same resected PNFs confirmed biallelic SC NF1 mutations; non-NF1 somatic SC variants were variable and present at low read number. We identified frequent germline variants as possible neurofibroma modifier genes. Genes harboring variants were validated in two additional cohorts of NF1 patients and by variant burden test. Genes including CUBN, CELSR2, COL14A1, ATR and ATM also showed decreased gene expression in some neurofibromas. ATM-relevant DNA repair defects were also present in a subset of neurofibromas with ATM variants, and in some neurofibroma SC. Heterozygous ATM G2023R or homozygous S707P variants reduced ATM protein expression in heterologous cells. In mice, genetic Atm heterozygosity promoted Schwann cell precursor self-renewal and increased tumor formation in vivo, suggesting that ATM variants contribute to neurofibroma initiation. We identify germline variants, rare in the general population, overrepresented in NF1 patients with neurofibromas. ATM and other identified genes are candidate modifiers of PNF pathogenesis.
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42
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Regional Gene Repression by DNA Double-Strand Breaks in G 1 Phase Cells. Mol Cell Biol 2019; 39:MCB.00181-19. [PMID: 31591143 DOI: 10.1128/mcb.00181-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Accepted: 09/24/2019] [Indexed: 01/12/2023] Open
Abstract
DNA damage responses (DDR) to double-strand breaks (DSBs) alter cellular transcription programs at the genome-wide level. Through processes that are less well understood, DSBs also alter transcriptional responses locally, which may be important for efficient DSB repair. Here, we developed an approach to elucidate the cis-acting responses to DSBs in G1 phase cells. We found that DSBs within a gene body silence its expression, as well as the transcription of local undamaged genes at a distance defined by the spread of γ-H2AX from the DSB. Importantly, DSBs not only repress ongoing transcription but also block the inducible expression of regional genes. DSB-mediated transcriptional repression depends on DDR signaling but does not require the generation of inaccessible chromatin. Our findings demonstrate that in G1 phase cells, DDR signaling establishes a robust and extensive region of transcriptional repression spreading from DSB sites and introduce an approach to study the mechanistic impact of targeted DNA breaks in nearly any chromatin environment.
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Krenning L, van den Berg J, Medema RH. Life or Death after a Break: What Determines the Choice? Mol Cell 2019; 76:346-358. [PMID: 31561953 DOI: 10.1016/j.molcel.2019.08.023] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/19/2019] [Accepted: 08/26/2019] [Indexed: 01/22/2023]
Abstract
DNA double-strand breaks (DSBs) pose a constant threat to genomic integrity. Such DSBs need to be repaired to preserve homeostasis at both the cellular and organismal levels. Hence, the DNA damage response (DDR) has evolved to repair these lesions and limit their toxicity. The initiation of DNA repair depends on the activation of the DDR, and we know that the strength of DDR signaling may differentially affect cellular viability. However, we do not fully understand what determines the cytotoxicity of a DSB. Recent work has identified genomic location, (in)correct DNA repair pathway usage, and cell-cycle position as contributors to DSB-induced cytotoxicity. In this review, we discuss how these determinants affect cytotoxicity, highlight recent discoveries, and identify open questions that could help to improve our understanding about cell fate decisions after a DNA DSB.
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Affiliation(s)
- Lenno Krenning
- Division of Cell Biology, Oncode Institute, Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Jeroen van den Berg
- Division of Cell Biology, Oncode Institute, Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - René H Medema
- Division of Cell Biology, Oncode Institute, Netherlands Cancer Institute, Amsterdam, the Netherlands.
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44
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Marnef A, Finoux AL, Arnould C, Guillou E, Daburon V, Rocher V, Mangeat T, Mangeot PE, Ricci EP, Legube G. A cohesin/HUSH- and LINC-dependent pathway controls ribosomal DNA double-strand break repair. Genes Dev 2019; 33:1175-1190. [PMID: 31395742 PMCID: PMC6719620 DOI: 10.1101/gad.324012.119] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 06/26/2019] [Indexed: 02/01/2023]
Abstract
The ribosomal DNA (rDNA) represents a particularly unstable locus undergoing frequent breakage. DNA double-strand breaks (DSBs) within rDNA induce both rDNA transcriptional repression and nucleolar segregation, but the link between the two events remains unclear. Here we found that DSBs induced on rDNA trigger transcriptional repression in a cohesin- and HUSH (human silencing hub) complex-dependent manner throughout the cell cycle. In S/G2 cells, transcriptional repression is further followed by extended resection within the interior of the nucleolus, DSB mobilization at the nucleolar periphery within nucleolar caps, and repair by homologous recombination. We showed that nuclear envelope invaginations frequently connect the nucleolus and that rDNA DSB mobilization, but not transcriptional repression, involves the nuclear envelope-associated LINC complex and the actin pathway. Altogether, our data indicate that rDNA break localization at the nucleolar periphery is not a direct consequence of transcriptional repression but rather is an active process that shares features with the mobilization of persistent DSB in active genes and heterochromatin.
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Affiliation(s)
- Aline Marnef
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Anne-Laure Finoux
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Coline Arnould
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Emmanuelle Guillou
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Virginie Daburon
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Vincent Rocher
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Thomas Mangeat
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Philippe E Mangeot
- International Center for Infectiology Research (CIRI), Ecole Normale Supérieure de Lyon (ENS), U1111, Institut National de la Santé et de la Recherche Médicale (INSERM), UMR5308, Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1, Université Lyon, Lyon F-6900, France
| | - Emiliano P Ricci
- Laboratoire de Biologie et Modélisation de la Cellule (LBMC), Ecole Normale Supérieure de Lyon (ENS), U1210, Institut National de la Santé et de la Recherche Médicale (INSERM), UMR5239, Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1, Université de Lyon, Lyon F-69007, France
| | - Gaëlle Legube
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
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45
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Arnould C, Legube G. The Secret Life of Chromosome Loops upon DNA Double-Strand Break. J Mol Biol 2019; 432:724-736. [PMID: 31401119 PMCID: PMC7057266 DOI: 10.1016/j.jmb.2019.07.036] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 07/24/2019] [Accepted: 07/30/2019] [Indexed: 12/22/2022]
Abstract
DNA double-strand breaks (DSBs) are harmful lesions that severely challenge genomic integrity, and recent evidence suggests that DSBs occur more frequently on the genome than previously thought. These lesions activate a complex and multilayered response called the DNA damage response, which allows to coordinate their repair with the cell cycle progression. While the mechanistic details of repair processes have been narrowed, thanks to several decades of intense studies, our knowledge of the impact of DSB on chromatin composition and chromosome architecture is still very sparse. However, the recent development of various tools to induce DSB at annotated loci, compatible with next-generation sequencing-based approaches, is opening a new framework to tackle these questions. Here we discuss the influence of initial and DSB-induced chromatin conformation and the strong potential of 3C-based technologies to decipher the contribution of chromosome architecture during DSB repair.
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Affiliation(s)
- Coline Arnould
- LBCMCP, Centre de Biologie Integrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Gaëlle Legube
- LBCMCP, Centre de Biologie Integrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France.
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46
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Varga D, Majoros H, Ujfaludi Z, Erdélyi M, Pankotai T. Quantification of DNA damage induced repair focus formation via super-resolution dSTORM localization microscopy. NANOSCALE 2019; 11:14226-14236. [PMID: 31317161 DOI: 10.1039/c9nr03696b] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In eukaryotic cells, each process, in which DNA is involved, should take place in the context of a chromatin structure. DNA double-strand breaks (DSBs) are one of the most deleterious lesions often leading to chromosomal rearrangement. In response to environmental stresses, cells have developed repair mechanisms to eliminate the DSBs. Upon DSB induction, several factors play roles in chromatin relaxation by catalysing the appropriate histone posttranslational modification (PTM) steps, therefore promoting the access of the repair factors to the DSBs. Among these PTMs, the phosphorylation of the histone variant H2AX at its Ser139 residue (also known as γH2AX) could be observed at the break sites. The structure of a DNA double-strand break induced repair focus has to be organized during the repair as it contributes to the accessibility of specific repair proteins to the damaged site. Our aim was to develop a quantitative approach to analyse the morphology of single repair foci by super-resolution dSTORM microscopy to gain insight into chromatin organization in DNA repair. We have established a specific dSTORM measurement process by developing a new analytical algorithm for gaining quantitative information about chromatin morphology and repair foci topology at an individual γH2AX enriched repair focus. Using this method we quantified single repair foci to show the distribution of γH2AX. The image of individual γH2AX referred to as the Single target Molecule response scatter Plot (SMPlot) was obtained by using high lateral resolution dSTORM images. Determination of the average localization numbers in an SMPlot was one of the key steps of quantitative dSTORM. A repair focus is made up of nanofoci. Such a substructure of repair foci can only be resolved and detected with super-resolution microscopy. Determination of the number of γH2AXs in the nanofoci was another key step of quantitative dSTORM. Additionally, based on our new analysis method, we were able to show the number of nucleosomes in each nanofocus that could allow us to define the possible chromatin structure and the nucleosome density around the break sites. This method is one of the first demonstrations of a single-cell based quantitative measurement of a discrete repair focus, which could provide new opportunities to categorize the spatial organization of nanofoci by parametric determination of topological similarity.
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Affiliation(s)
- Dániel Varga
- University of Szeged, Department of Optics and Quantum Electronics, Hungary.
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47
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Schrank B, Gautier J. Assembling nuclear domains: Lessons from DNA repair. J Cell Biol 2019; 218:2444-2455. [PMID: 31324649 PMCID: PMC6683749 DOI: 10.1083/jcb.201904202] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/24/2019] [Accepted: 06/27/2019] [Indexed: 12/14/2022] Open
Abstract
Schrank and Gautier discuss the generation and function of nuclear domains during DNA repair with a special focus on nuclear actin polymerization. Eukaryotic nuclei are organized into nuclear domains that unite loci sharing a common function. These domains are essential for diverse processes including (1) the formation of topologically associated domains (TADs) that coordinate replication and transcription, (2) the formation of specialized transcription and splicing factories, and (3) the clustering of DNA double-strand breaks (DSBs), which concentrates damaged DNA for repair. The generation of nuclear domains requires forces that are beginning to be identified. In the case of DNA DSBs, DNA movement and clustering are driven by actin filament nucleators. Furthermore, RNAs and low-complexity protein domains such as RNA-binding proteins also accumulate around sites of transcription and repair. The link between liquid–liquid phase separation and actin nucleation in the formation of nuclear domains is still unknown. This review discusses DSB repair domain formation as a model for functional nuclear domains in other genomic contexts.
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Affiliation(s)
- Benjamin Schrank
- Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, NY
| | - Jean Gautier
- Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, NY
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48
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Quantitative mechanisms of DNA damage sensing and signaling. Curr Genet 2019; 66:59-62. [PMID: 31227863 PMCID: PMC7021746 DOI: 10.1007/s00294-019-01007-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 06/13/2019] [Accepted: 06/14/2019] [Indexed: 11/13/2022]
Abstract
DNA damage occurs abundantly during normal cellular proliferation. This necessitates that cellular DNA damage response and checkpoint pathways monitor the cellular DNA damage load and that DNA damage signaling is quantitative. Yet, how DNA lesions are counted and converted into a quantitative response remains poorly understood. We have recently obtained insights into this question investigating DNA damage signaling elicited by single-stranded DNA (ssDNA). Intriguingly, our findings suggest that local and global DNA damage signaling react differentially to increasing amounts of DNA damage. In this mini-review, we will discuss these findings and put them into perspective of current knowledge on the DNA damage response.
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49
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Zhu Y, Biernacka A, Pardo B, Dojer N, Forey R, Skrzypczak M, Fongang B, Nde J, Yousefi R, Pasero P, Ginalski K, Rowicka M. qDSB-Seq is a general method for genome-wide quantification of DNA double-strand breaks using sequencing. Nat Commun 2019; 10:2313. [PMID: 31127121 PMCID: PMC6534554 DOI: 10.1038/s41467-019-10332-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 04/30/2019] [Indexed: 12/04/2022] Open
Abstract
DNA double-strand breaks (DSBs) are among the most lethal types of DNA damage and frequently cause genome instability. Sequencing-based methods for mapping DSBs have been developed but they allow measurement only of relative frequencies of DSBs between loci, which limits our understanding of the physiological relevance of detected DSBs. Here we propose quantitative DSB sequencing (qDSB-Seq), a method providing both DSB frequencies per cell and their precise genomic coordinates. We induce spike-in DSBs by a site-specific endonuclease and use them to quantify detected DSBs (labeled, e.g., using i-BLESS). Utilizing qDSB-Seq, we determine numbers of DSBs induced by a radiomimetic drug and replication stress, and reveal two orders of magnitude differences in DSB frequencies. We also measure absolute frequencies of Top1-dependent DSBs at natural replication fork barriers. qDSB-Seq is compatible with various DSB labeling methods in different organisms and allows accurate comparisons of absolute DSB frequencies across samples.
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Affiliation(s)
- Yingjie Zhu
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, Texas, 77555, USA
| | - Anna Biernacka
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02-089, Warsaw, Poland
| | - Benjamin Pardo
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, 141 rue de la Cardonille, Montpellier, 34396, France
| | - Norbert Dojer
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, Texas, 77555, USA
- Institute of Informatics, University of Warsaw, Stefana Banacha 2, 02-097, Warsaw, Poland
| | - Romain Forey
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, 141 rue de la Cardonille, Montpellier, 34396, France
| | - Magdalena Skrzypczak
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02-089, Warsaw, Poland
| | - Bernard Fongang
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, Texas, 77555, USA
| | - Jules Nde
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, Texas, 77555, USA
| | - Razie Yousefi
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, Texas, 77555, USA
| | - Philippe Pasero
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, 141 rue de la Cardonille, Montpellier, 34396, France
| | - Krzysztof Ginalski
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02-089, Warsaw, Poland
| | - Maga Rowicka
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, Texas, 77555, USA.
- Institute for Translational Sciences, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, Texas, 77555, USA.
- Sealy Center for Molecular Medicine, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, Texas, 77555, USA.
- Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX, 77555, USA.
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50
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So CC, Ramachandran S, Martin A. E3 Ubiquitin Ligases RNF20 and RNF40 Are Required for Double-Stranded Break (DSB) Repair: Evidence for Monoubiquitination of Histone H2B Lysine 120 as a Novel Axis of DSB Signaling and Repair. Mol Cell Biol 2019; 39:e00488-18. [PMID: 30692271 PMCID: PMC6447412 DOI: 10.1128/mcb.00488-18] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 11/13/2018] [Accepted: 01/23/2019] [Indexed: 01/13/2023] Open
Abstract
Histone posttranslational modifications play fundamental roles in the regulation of double-stranded DNA break (DSB) repair. RNF20/RNF40-mediated monoubiquitination of histone H2B on lysine 120 (H2Bub) has been suggested as a potential mediator of DSB repair, although the nature and function of this posttranslational modification remain enigmatic. In this report, we demonstrate that RNF20 and RNF40 are required for DSB repair leading to homologous recombination (HR) and class switch recombination, a process driven by nonhomologous end joining (NHEJ), in mouse B cells. These findings suggest a role for RNF20 and RNF40 in DSB repair proximal to NHEJ/HR pathway choice and likely in the signaling of DSBs. We found that DSBs led to a global increase in H2Bub but not the transcription-associated posttranslational modifications H3K4me3 and H3K79me2. We also found that H2AX phosphorylation was dispensable for H2Bub and that ATM and ATR jointly regulate ionizing radiation (IR)-induced H2Bub. Together, our results suggest that RNF20, RNF40, and H2Bub may represent a novel pathway for DSB sensing and repair.
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Affiliation(s)
- Clare C So
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | | | - Alberto Martin
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
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