1
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Abbouche L, Murphy V, Gao J, van Twest S, Sobinoff A, Auweiler K, Pickett H, Bythell-Douglas R, Deans A. Mechanism of structure-specific DNA binding by the FANCM branchpoint translocase. Nucleic Acids Res 2024; 52:11029-11044. [PMID: 39189453 PMCID: PMC11472164 DOI: 10.1093/nar/gkae727] [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: 05/28/2024] [Revised: 07/31/2024] [Accepted: 08/09/2024] [Indexed: 08/28/2024] Open
Abstract
FANCM is a DNA repair protein that recognizes stalled replication forks, and recruits downstream repair factors. FANCM activity is also essential for the survival of cancer cells that utilize the Alternative Lengthening of Telomeres (ALT) mechanism. FANCM efficiently recognizes stalled replication forks in the genome or at telomeres through its strong affinity for branched DNA structures. In this study, we demonstrate that the N-terminal translocase domain drives this specific branched DNA recognition. The Hel2i subdomain within the translocase is crucial for effective substrate engagement and couples DNA binding to catalytic ATP-dependent branch migration. Removal of Hel2i or mutation of key DNA-binding residues within this domain diminished FANCM's affinity for junction DNA and abolished branch migration activity. Importantly, these mutant FANCM variants failed to rescue the cell cycle arrest, telomere-associated replication stress, or lethality of ALT-positive cancer cells depleted of endogenous FANCM. Our results reveal the Hel2i domain is key for FANCM to properly engage DNA substrates, and therefore plays an essential role in its tumour-suppressive functions by restraining the hyperactivation of the ALT pathway.
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Affiliation(s)
- Lara Abbouche
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
- Department of Medicine (St Vincent's), University of Melbourne, Fitzroy, VIC, Australia
| | - Vincent J Murphy
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
| | - Jixuan Gao
- Children's Medical Research Institute, Westmead, NSW, Australia
| | - Sylvie van Twest
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
| | | | - Karen M Auweiler
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
- Julius-Maximilians-University of Würzburg, Germany
| | - Hilda A Pickett
- Children's Medical Research Institute, Westmead, NSW, Australia
| | - Rohan Bythell-Douglas
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
| | - Andrew J Deans
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
- Department of Medicine (St Vincent's), University of Melbourne, Fitzroy, VIC, Australia
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2
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Adolph MB, Cortez D. Mechanisms and regulation of replication fork reversal. DNA Repair (Amst) 2024; 141:103731. [PMID: 39089193 DOI: 10.1016/j.dnarep.2024.103731] [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: 04/24/2024] [Revised: 07/15/2024] [Accepted: 07/17/2024] [Indexed: 08/03/2024]
Abstract
DNA replication is remarkably accurate with estimates of only a handful of mutations per human genome per cell division cycle. Replication stress caused by DNA lesions, transcription-replication conflicts, and other obstacles to the replication machinery must be efficiently overcome in ways that minimize errors and maximize completion of DNA synthesis. Replication fork reversal is one mechanism that helps cells tolerate replication stress. This process involves reannealing of parental template DNA strands and generation of a nascent-nascent DNA duplex. While fork reversal may be beneficial by facilitating DNA repair or template switching, it must be confined to the appropriate contexts to preserve genome stability. Many enzymes have been implicated in this process including ATP-dependent DNA translocases like SMARCAL1, ZRANB3, HLTF, and the helicase FBH1. In addition, the RAD51 recombinase is required. Many additional factors and regulatory activities also act to ensure reversal is beneficial instead of yielding undesirable outcomes. Finally, reversed forks must also be stabilized and often need to be restarted to complete DNA synthesis. Disruption or deregulation of fork reversal causes a variety of human diseases. In this review we will describe the latest models for reversal and key mechanisms of regulation.
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Affiliation(s)
- Madison B Adolph
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, United States
| | - David Cortez
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, United States.
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3
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van de Kooij B, van der Wal FJ, Rother MB, Wiegant WW, Creixell P, Stout M, Joughin BA, Vornberger J, Altmeyer M, van Vugt MATM, Yaffe MB, van Attikum H. The Fanconi anemia core complex promotes CtIP-dependent end resection to drive homologous recombination at DNA double-strand breaks. Nat Commun 2024; 15:7076. [PMID: 39152113 PMCID: PMC11329772 DOI: 10.1038/s41467-024-51090-6] [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: 09/11/2023] [Accepted: 07/17/2024] [Indexed: 08/19/2024] Open
Abstract
During the repair of interstrand crosslinks (ICLs) a DNA double-strand break (DSB) is generated. The Fanconi anemia (FA) core complex, which is recruited to ICLs, promotes high-fidelity repair of this DSB by homologous recombination (HR). However, whether the FA core complex also promotes HR at ICL-independent DSBs, for example induced by ionizing irradiation or nucleases, remains controversial. Here, we identified the FA core complex members FANCL and Ube2T as HR-promoting factors in a CRISPR/Cas9-based screen. Using isogenic cell line models, we further demonstrated an HR-promoting function of FANCL and Ube2T, and of their ubiquitination substrate FANCD2. We show that FANCL and Ube2T localize at DSBs in a FANCM-dependent manner, and are required for the DSB accumulation of FANCD2. Mechanistically, we demonstrate that FANCL ubiquitin ligase activity is required for the accumulation of CtIP at DSBs, thereby promoting end resection and Rad51 loading. Together, these data demonstrate a dual genome maintenance function of the FA core complex and FANCD2 in promoting repair of both ICLs and DSBs.
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Affiliation(s)
- Bert van de Kooij
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands.
- Koch Institute for Integrative Cancer Research, MIT Center for Precision Cancer Medicine, Departments of Biology and Bioengineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
| | - Fenna J van der Wal
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Magdalena B Rother
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Wouter W Wiegant
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Pau Creixell
- Koch Institute for Integrative Cancer Research, MIT Center for Precision Cancer Medicine, Departments of Biology and Bioengineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- CRUK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
| | - Merula Stout
- Department of Molecular Mechanisms of Disease, University of Zurich (UZH), Zurich, Switzerland
| | - Brian A Joughin
- Koch Institute for Integrative Cancer Research, MIT Center for Precision Cancer Medicine, Departments of Biology and Bioengineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Julia Vornberger
- Department of Molecular Mechanisms of Disease, University of Zurich (UZH), Zurich, Switzerland
| | - Matthias Altmeyer
- Department of Molecular Mechanisms of Disease, University of Zurich (UZH), Zurich, Switzerland
| | - Marcel A T M van Vugt
- Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Michael B Yaffe
- Koch Institute for Integrative Cancer Research, MIT Center for Precision Cancer Medicine, Departments of Biology and Bioengineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Surgery, Beth Israel Deaconess Medical Center, Divisions of Acute Care Surgery, Trauma, and Critical Care and Surgical Oncology, Harvard Medical School, Boston, USA.
| | - Haico van Attikum
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands.
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4
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Abbouche L, Bythell-Douglas R, Deans AJ. FANCM branchpoint translocase: Master of traverse, reverse and adverse DNA repair. DNA Repair (Amst) 2024; 140:103701. [PMID: 38878565 DOI: 10.1016/j.dnarep.2024.103701] [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: 01/16/2024] [Revised: 05/15/2024] [Accepted: 05/30/2024] [Indexed: 07/13/2024]
Abstract
FANCM is a multifunctional DNA repair enzyme that acts as a sensor and coordinator of replication stress responses, especially interstrand crosslink (ICL) repair mediated by the Fanconi anaemia (FA) pathway. Its specialised ability to bind and remodel branched DNA structures enables diverse genome maintenance activities. Through ATP-powered "branchpoint translocation", FANCM can promote fork reversal, facilitate replication traverse of ICLs, resolve deleterious R-loop structures, and restrain recombination. These remodelling functions also support a role as sensor of perturbed replication, eliciting checkpoint signalling and recruitment of downstream repair factors like the Fanconi anaemia FANCI:FANCD2 complex. Accordingly, FANCM deficiency causes chromosome fragility and cancer susceptibility. Other recent advances link FANCM to roles in gene editing efficiency and meiotic recombination, along with emerging synthetic lethal relationships, and targeting opportunities in ALT-positive cancers. Here we review key properties of FANCM's biochemical activities, with a particular focus on branchpoint translocation as a distinguishing characteristic.
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Affiliation(s)
- Lara Abbouche
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia; Department of Medicine (St Vincent's), University of Melbourne, Fitzroy, VIC, Australia
| | - Rohan Bythell-Douglas
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
| | - Andrew J Deans
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia; Department of Medicine (St Vincent's), University of Melbourne, Fitzroy, VIC, Australia.
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5
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Herr LM, Schaffer ED, Fuchs KF, Datta A, Brosh RM. Replication stress as a driver of cellular senescence and aging. Commun Biol 2024; 7:616. [PMID: 38777831 PMCID: PMC11111458 DOI: 10.1038/s42003-024-06263-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 04/29/2024] [Indexed: 05/25/2024] Open
Abstract
Replication stress refers to slowing or stalling of replication fork progression during DNA synthesis that disrupts faithful copying of the genome. While long considered a nexus for DNA damage, the role of replication stress in aging is under-appreciated. The consequential role of replication stress in promotion of organismal aging phenotypes is evidenced by an extensive list of hereditary accelerated aging disorders marked by molecular defects in factors that promote replication fork progression and operate uniquely in the replication stress response. Additionally, recent studies have revealed cellular pathways and phenotypes elicited by replication stress that align with designated hallmarks of aging. Here we review recent advances demonstrating the role of replication stress as an ultimate driver of cellular senescence and aging. We discuss clinical implications of the intriguing links between cellular senescence and aging including application of senotherapeutic approaches in the context of replication stress.
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Affiliation(s)
- Lauren M Herr
- Helicases and Genomic Integrity Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Ethan D Schaffer
- Helicases and Genomic Integrity Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Kathleen F Fuchs
- Helicases and Genomic Integrity Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Arindam Datta
- Helicases and Genomic Integrity Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA.
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Robert M Brosh
- Helicases and Genomic Integrity Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA.
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6
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Stewart GS. DONSON: Slding in 2 the limelight. DNA Repair (Amst) 2024; 134:103616. [PMID: 38159447 DOI: 10.1016/j.dnarep.2023.103616] [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: 08/25/2023] [Revised: 11/18/2023] [Accepted: 12/19/2023] [Indexed: 01/03/2024]
Abstract
For over a decade, it has been known that yeast Sld2, Dpb11, GINS and Polε form the pre-loading complex (pre-LC), which is recruited to a CDC45-bound MCM2-7 complex by the Sld3/Sld7 heterodimer in a phospho-dependent manner. Whilst functional orthologs of Dbp11 (TOPBP1), Sld3 (TICRR) and Sld7 (MTBP) have been identified in metazoans, controversy has surrounded the identity of the Sld2 ortholog. It was originally proposed that the RECQ helicase, RECQL4, which is mutated in Rothmund-Thomson syndrome, represented the closest vertebrate ortholog of Sld2 due to a small region of sequence homology at its N-Terminus. However, there is no clear evidence that RECQL4 is required for CMG loading. Recently, new findings suggest that the functional ortholog of Sld2 is actually DONSON, a replication fork stability factor mutated in a range of neurodevelopmental disorders characterised by microcephaly, short stature and limb abnormalities. These studies show that DONSON forms a complex with TOPBP1, GINS and Polε analogous to the pre-LC in yeast, which is required to position the GINS complex on the MCM complex and initiate DNA replication. Taken together with previously published functions for DONSON, these observations indicate that DONSON plays two roles in regulating DNA replication, one in promoting replication initiation and one in stabilising the fork during elongation. Combined, these findings may help to uncover why DONSON mutations are associated with such a wide range of clinical deficits.
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Affiliation(s)
- Grant S Stewart
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.
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7
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Ito M, Fujita Y, Shinohara A. Positive and negative regulators of RAD51/DMC1 in homologous recombination and DNA replication. DNA Repair (Amst) 2024; 134:103613. [PMID: 38142595 DOI: 10.1016/j.dnarep.2023.103613] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 12/10/2023] [Accepted: 12/10/2023] [Indexed: 12/26/2023]
Abstract
RAD51 recombinase plays a central role in homologous recombination (HR) by forming a nucleoprotein filament on single-stranded DNA (ssDNA) to catalyze homology search and strand exchange between the ssDNA and a homologous double-stranded DNA (dsDNA). The catalytic activity of RAD51 assembled on ssDNA is critical for the DNA-homology-mediated repair of DNA double-strand breaks in somatic and meiotic cells and restarting stalled replication forks during DNA replication. The RAD51-ssDNA complex also plays a structural role in protecting the regressed/reversed replication fork. Two types of regulators control RAD51 filament formation, stability, and dynamics, namely positive regulators, including mediators, and negative regulators, so-called remodelers. The appropriate balance of action by the two regulators assures genome stability. This review describes the roles of positive and negative RAD51 regulators in HR and DNA replication and its meiosis-specific homolog DMC1 in meiotic recombination. We also provide future study directions for a comprehensive understanding of RAD51/DMC1-mediated regulation in maintaining and inheriting genome integrity.
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Affiliation(s)
- Masaru Ito
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
| | - Yurika Fujita
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
| | - Akira Shinohara
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
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8
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van de Kooij B, van der Wal FJ, Rother MB, Creixell P, Stout M, Wiegant W, Joughin BA, Vornberger J, van Vugt MA, Altmeyer M, Yaffe MB, van Attikum H. The Fanconi anemia core complex promotes CtIP-dependent end-resection to drive homologous recombination at DNA double-strand breaks. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.05.556391. [PMID: 37732274 PMCID: PMC10508776 DOI: 10.1101/2023.09.05.556391] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
Homologous Recombination (HR) is a high-fidelity repair mechanism of DNA Double-Strand Breaks (DSBs), which are induced by irradiation, genotoxic chemicals or physiological DNA damaging processes. DSBs are also generated as intermediates during the repair of interstrand crosslinks (ICLs). In this context, the Fanconi anemia (FA) core complex, which is effectively recruited to ICLs, promotes HR-mediated DSB-repair. However, whether the FA core complex also promotes HR at ICL-independent DSBs remains controversial. Here, we identified the FA core complex members FANCL and Ube2T as HR-promoting factors in a CRISPR/Cas9-based screen with cells carrying the DSB-repair reporter DSB-Spectrum. Using isogenic cell-line models, we validated the HR-function of FANCL and Ube2T, and demonstrated a similar function for their ubiquitination-substrate FANCD2. We further show that FANCL and Ube2T are directly recruited to DSBs and are required for the accumulation of FANCD2 at these break sites. Mechanistically, we demonstrate that FANCL ubiquitin ligase activity is required for the accumulation of the nuclease CtIP at DSBs, and consequently for optimal end-resection and Rad51 loading. CtIP overexpression rescues HR in FANCL-deficient cells, validating that FANCL primarily regulates HR by promoting CtIP recruitment. Together, these data demonstrate that the FA core complex and FANCD2 have a dual genome maintenance function by promoting repair of DSBs as well as the repair of ICLs.
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Affiliation(s)
- Bert van de Kooij
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
- Current address: Department of Medical Oncology, University Medical Center Groningen, University of Groningen, the Netherlands
| | - Fenna J. van der Wal
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Magdalena B. Rother
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Pau Creixell
- Koch Institute for Integrative Cancer Research, MIT Center for Precision Cancer Medicine, Departments of Biology and Bioengineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Current address: CRUK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
| | - Merula Stout
- Department of Molecular Mechanisms of Disease, University of Zurich (UZH), Zurich, Switzerland
| | - Wouter Wiegant
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Brian A. Joughin
- Koch Institute for Integrative Cancer Research, MIT Center for Precision Cancer Medicine, Departments of Biology and Bioengineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Julia Vornberger
- Department of Molecular Mechanisms of Disease, University of Zurich (UZH), Zurich, Switzerland
| | - Marcel A.T.M. van Vugt
- Department of Medical Oncology, University Medical Center Groningen, University of Groningen, the Netherlands
| | - Matthias Altmeyer
- Department of Molecular Mechanisms of Disease, University of Zurich (UZH), Zurich, Switzerland
| | - Michael B. Yaffe
- Koch Institute for Integrative Cancer Research, MIT Center for Precision Cancer Medicine, Departments of Biology and Bioengineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Surgery, Beth Israel Deaconess Medical Center, Divisions of Acute Care Surgery, Trauma, and Critical Care and Surgical Oncology, Harvard Medical School, Boston
| | - Haico van Attikum
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
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9
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Venkadakrishnan J, Lahane G, Dhar A, Xiao W, Bhat KM, Pandita TK, Bhat A. Implications of Translesion DNA Synthesis Polymerases on Genomic Stability and Human Health. Mol Cell Biol 2023; 43:401-425. [PMID: 37439479 PMCID: PMC10448981 DOI: 10.1080/10985549.2023.2224199] [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: 01/31/2023] [Revised: 05/03/2023] [Accepted: 06/01/2023] [Indexed: 07/14/2023] Open
Abstract
Replication fork arrest-induced DNA double strand breaks (DSBs) caused by lesions are effectively suppressed in cells due to the presence of a specialized mechanism, commonly referred to as DNA damage tolerance (DDT). In eukaryotic cells, DDT is facilitated through translesion DNA synthesis (TLS) carried out by a set of DNA polymerases known as TLS polymerases. Another parallel mechanism, referred to as homology-directed DDT, is error-free and involves either template switching or fork reversal. The significance of the DDT pathway is well established. Several diseases have been attributed to defects in the TLS pathway, caused either by mutations in the TLS polymerase genes or dysregulation. In the event of a replication fork encountering a DNA lesion, cells switch from high-fidelity replicative polymerases to low-fidelity TLS polymerases, which are associated with genomic instability linked with several human diseases including, cancer. The role of TLS polymerases in chemoresistance has been recognized in recent years. In addition to their roles in the DDT pathway, understanding noncanonical functions of TLS polymerases is also a key to unraveling their importance in maintaining genomic stability. Here we summarize the current understanding of TLS pathway in DDT and its implication for human health.
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Affiliation(s)
| | - Ganesh Lahane
- Department of Pharmacy, Birla Institute of Technology and Sciences Pilani, Hyderabad Campus, Hyderabad, India
| | - Arti Dhar
- Department of Pharmacy, Birla Institute of Technology and Sciences Pilani, Hyderabad Campus, Hyderabad, India
| | - Wei Xiao
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Canada
| | - Krishna Moorthi Bhat
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, USA
| | - Tej K. Pandita
- Center for Genomics and Precision Medicine, Texas A&M College of Medicine, Houston, Texas, USA
| | - Audesh Bhat
- Center for Molecular Biology, Central University of Jammu, UT Jammu and Kashmir, India
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10
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Strelnikova SR, Komakhin RA. Control of meiotic crossing over in plant breeding. Vavilovskii Zhurnal Genet Selektsii 2023; 27:99-110. [PMID: 37063511 PMCID: PMC10090103 DOI: 10.18699/vjgb-23-15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 09/11/2022] [Accepted: 09/26/2022] [Indexed: 04/18/2023] Open
Abstract
Meiotic crossing over is the main mechanism for constructing a new allelic composition of individual chromosomes and is necessary for the proper distribution of homologous chromosomes between gametes. The parameters of meiotic crossing over that have developed in the course of evolution are determined by natural selection and do not fully suit the tasks of selective breeding research. This review summarizes the results of experimental studies aimed at increasing the frequency of crossovers and redistributing their positions along chromosomes using genetic manipulations at different stages of meiotic recombination. The consequences of inactivation and/or overexpression of the SPO11 genes, the products of which generate meiotic double-strand breaks in DNA, for the redistribution of crossover positions in the genome of various organisms are discussed. The results of studies concerning the effect of inactivation or overexpression of genes encoding RecA-like recombinases on meiotic crossing over, including those in cultivated tomato (Solanum lycopersicum L.) and its interspecific hybrids, are summarized. The consequences of inactivation of key genes of the mismatch repair system are discussed. Their suppression made it possible to significantly increase the frequency of meiotic recombination between homeologues in the interspecific hybrid yeast Saccharomyces cerevisiae × S. paradoxus and between homologues in arabidopsis plants (Arabidopsis thaliana L.). Also discussed are attempts to extrapolate these results to other plant species, in which a decrease in reproductive properties and microsatellite instability in the genome have been noted. The most significant results on the meiotic recombination frequency increase upon inactivation of the FANCM, TOP3α, RECQ4, FIGL1 crossover repressor genes and upon overexpression of the HEI10 crossover enhancer gene are separately described. In some experiments, the increase of meiotic recombination frequency by almost an order of magnitude and partial redistribution of the crossover positions along chromosomes were achieved in arabidopsis while fully preserving fecundity. Similar results have been obtained for some crops.
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Affiliation(s)
- S R Strelnikova
- All-Russia Research Institute of Agricultural Biotechnology, Moscow, Russia
| | - R A Komakhin
- All-Russia Research Institute of Agricultural Biotechnology, Moscow, Russia
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11
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Mechetin GV, Zharkov DO. DNA Damage Response and Repair in Boron Neutron Capture Therapy. Genes (Basel) 2023; 14:127. [PMID: 36672868 PMCID: PMC9859301 DOI: 10.3390/genes14010127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 01/03/2023] Open
Abstract
Boron neutron capture therapy (BNCT) is an approach to the radiotherapy of solid tumors that was first outlined in the 1930s but has attracted considerable attention recently with the advent of a new generation of neutron sources. In BNCT, tumor cells accumulate 10B atoms that react with epithermal neutrons, producing energetic α particles and 7Li atoms that damage the cell's genome. The damage inflicted by BNCT appears not to be easily repairable and is thus lethal for the cell; however, the molecular events underlying the action of BNCT remain largely unaddressed. In this review, the chemistry of DNA damage during BNCT is outlined, the major mechanisms of DNA break sensing and repair are summarized, and the specifics of the repair of BNCT-induced DNA lesions are discussed.
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Affiliation(s)
- Grigory V. Mechetin
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia
| | - Dmitry O. Zharkov
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia
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12
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Abstract
High-fidelity DNA replication is critical for the faithful transmission of genetic information to daughter cells. Following genotoxic stress, specialized DNA damage tolerance pathways are activated to ensure replication fork progression. These pathways include translesion DNA synthesis, template switching and repriming. In this Review, we describe how DNA damage tolerance pathways impact genome stability, their connection with tumorigenesis and their effects on cancer therapy response. We discuss recent findings that single-strand DNA gap accumulation impacts chemoresponse and explore a growing body of evidence that suggests that different DNA damage tolerance factors, including translesion synthesis polymerases, template switching proteins and enzymes affecting single-stranded DNA gaps, represent useful cancer targets. We further outline how the consequences of DNA damage tolerance mechanisms could inform the discovery of new biomarkers to refine cancer therapies.
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Affiliation(s)
- Emily Cybulla
- Division of Oncology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO, USA
| | - Alessandro Vindigni
- Division of Oncology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA.
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13
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Gao J, Pickett HA. Targeting telomeres: advances in telomere maintenance mechanism-specific cancer therapies. Nat Rev Cancer 2022; 22:515-532. [PMID: 35790854 DOI: 10.1038/s41568-022-00490-1] [Citation(s) in RCA: 77] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/25/2022] [Indexed: 12/31/2022]
Abstract
Cancer cells establish replicative immortality by activating a telomere-maintenance mechanism (TMM), be it telomerase or the alternative lengthening of telomeres (ALT) pathway. Targeting telomere maintenance represents an intriguing opportunity to treat the vast majority of all cancer types. Whilst telomerase inhibitors have historically been heralded as promising anticancer agents, the reality has been more challenging, and there are currently no therapeutic options for cancer types that use ALT despite their aggressive nature and poor prognosis. In this Review, we discuss the mechanistic differences between telomere maintenance by telomerase and ALT, the current methods used to detect each mechanism, the utility of these tests for clinical diagnosis, and recent developments in the therapeutic strategies being employed to target both telomerase and ALT. We present notable developments in repurposing established therapeutic agents and new avenues that are emerging to target cancer types according to which TMM they employ. These opportunities extend beyond inhibition of telomere maintenance, by finding and exploiting inherent weaknesses in the telomeres themselves to trigger rapid cellular effects that lead to cell death.
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Affiliation(s)
- Jixuan Gao
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW, Australia
| | - Hilda A Pickett
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW, Australia.
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14
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Halder S, Sanchez A, Ranjha L, Reginato G, Ceppi I, Acharya A, Anand R, Cejka P. Double-stranded DNA binding function of RAD51 in DNA protection and its regulation by BRCA2. Mol Cell 2022; 82:3553-3565.e5. [PMID: 36070766 DOI: 10.1016/j.molcel.2022.08.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 06/16/2022] [Accepted: 08/10/2022] [Indexed: 11/26/2022]
Abstract
RAD51 and the breast cancer suppressor BRCA2 have critical functions in DNA double-strand (dsDNA) break repair by homologous recombination and the protection of newly replicated DNA from nucleolytic degradation. The recombination function of RAD51 requires its binding to single-stranded DNA (ssDNA), whereas binding to dsDNA is inhibitory. Using reconstituted MRE11-, EXO1-, and DNA2-dependent nuclease reactions, we show that the protective function of RAD51 unexpectedly depends on its binding to dsDNA. The BRC4 repeat of BRCA2 abrogates RAD51 binding to dsDNA and accordingly impairs the function of RAD51 in protection. The BRCA2 C-terminal RAD51-binding segment (TR2) acts in a dominant manner to overcome the effect of BRC4. Mechanistically, TR2 stabilizes RAD51 binding to dsDNA, even in the presence of BRC4, promoting DNA protection. Our data suggest that RAD51's dsDNA-binding capacity may have evolved together with its function in replication fork protection and provide a mechanistic basis for the DNA-protection function of BRCA2.
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Affiliation(s)
- Swagata Halder
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, 6500 Bellinzona, Switzerland
| | - Aurore Sanchez
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, 6500 Bellinzona, Switzerland
| | - Lepakshi Ranjha
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, 6500 Bellinzona, Switzerland
| | - Giordano Reginato
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, 6500 Bellinzona, Switzerland; Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), 8049 Zürich, Switzerland
| | - Ilaria Ceppi
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, 6500 Bellinzona, Switzerland; Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), 8049 Zürich, Switzerland
| | - Ananya Acharya
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, 6500 Bellinzona, Switzerland; Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), 8049 Zürich, Switzerland
| | - Roopesh Anand
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, 6500 Bellinzona, Switzerland
| | - Petr Cejka
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, 6500 Bellinzona, Switzerland; Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), 8049 Zürich, Switzerland.
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15
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Fiesco-Roa MÓ, García-de Teresa B, Leal-Anaya P, van ‘t Hek R, Wegman-Ostrosky T, Frías S, Rodríguez A. Fanconi anemia and dyskeratosis congenita/telomere biology disorders: Two inherited bone marrow failure syndromes with genomic instability. Front Oncol 2022; 12:949435. [PMID: 36091172 PMCID: PMC9453478 DOI: 10.3389/fonc.2022.949435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
Inherited bone marrow failure syndromes (IBMFS) are a complex and heterogeneous group of genetic diseases. To date, at least 13 IBMFS have been characterized. Their pathophysiology is associated with germline pathogenic variants in genes that affect hematopoiesis. A couple of these diseases also have genomic instability, Fanconi anemia due to DNA damage repair deficiency and dyskeratosis congenita/telomere biology disorders as a result of an alteration in telomere maintenance. Patients can have extramedullary manifestations, including cancer and functional or structural physical abnormalities. Furthermore, the phenotypic spectrum varies from cryptic features to patients with significantly evident manifestations. These diseases require a high index of suspicion and should be considered in any patient with abnormal hematopoiesis, even if extramedullary manifestations are not evident. This review describes the disrupted cellular processes that lead to the affected maintenance of the genome structure, contrasting the dysmorphological and oncological phenotypes of Fanconi anemia and dyskeratosis congenita/telomere biology disorders. Through a dysmorphological analysis, we describe the phenotypic features that allow to make the differential diagnosis and the early identification of patients, even before the onset of hematological or oncological manifestations. From the oncological perspective, we analyzed the spectrum and risks of cancers in patients and carriers.
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Affiliation(s)
- Moisés Ó. Fiesco-Roa
- Laboratorio de Citogenética, Instituto Nacional de Pediatría, Ciudad de México, Mexico
- Maestría y Doctorado en Ciencias Médicas, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, Ciudad de México, Mexico
| | | | - Paula Leal-Anaya
- Departamento de Genética Humana, Instituto Nacional de Pediatría, Ciudad de México, Mexico
| | - Renée van ‘t Hek
- Facultad de Medicina, Universidad Nacional Autoínoma de Meíxico (UNAM), Ciudad Universitaria, Ciudad de México, Mexico
| | - Talia Wegman-Ostrosky
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, Ciudad de México, Mexico
| | - Sara Frías
- Laboratorio de Citogenética, Instituto Nacional de Pediatría, Ciudad de México, Mexico
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, Mexico
- *Correspondence: Alfredo Rodríguez, ; Sara Frías,
| | - Alfredo Rodríguez
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, Mexico
- Unidad de Genética de la Nutrición, Instituto Nacional de Pediatría, Ciudad de México, Mexico
- *Correspondence: Alfredo Rodríguez, ; Sara Frías,
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16
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Halder S, Ranjha L, Taglialatela A, Ciccia A, Cejka P. Strand annealing and motor driven activities of SMARCAL1 and ZRANB3 are stimulated by RAD51 and the paralog complex. Nucleic Acids Res 2022; 50:8008-8022. [PMID: 35801922 PMCID: PMC9371921 DOI: 10.1093/nar/gkac583] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 06/13/2022] [Accepted: 06/23/2022] [Indexed: 12/17/2022] Open
Abstract
SMARCAL1, ZRANB3 and HLTF are required for the remodeling of replication forks upon stress to promote genome stability. RAD51, along with the RAD51 paralog complex, were also found to have recombination-independent functions in fork reversal, yet the underlying mechanisms remained unclear. Using reconstituted reactions, we build upon previous data to show that SMARCAL1, ZRANB3 and HLTF have unequal biochemical capacities, explaining why they have non-redundant functions. SMARCAL1 uniquely anneals RPA-coated ssDNA, which depends on its direct interaction with RPA, but not on ATP. SMARCAL1, along with ZRANB3, but not HLTF efficiently employ ATPase driven translocase activity to rezip RPA-covered bubbled DNA, which was proposed to mimic elements of fork reversal. In contrast, ZRANB3 and HLTF but not SMARCAL1 are efficient in branch migration that occurs downstream in fork remodeling. We also show that low concentrations of RAD51 and the RAD51 paralog complex, RAD51B–RAD51C–RAD51D–XRCC2 (BCDX2), directly stimulate the motor-driven activities of SMARCAL1 and ZRANB3 but not HLTF, and the interplay is underpinned by physical interactions. Our data provide a possible mechanism explaining previous cellular experiments implicating RAD51 and BCDX2 in fork reversal.
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Affiliation(s)
- Swagata Halder
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, Switzerland
| | - Lepakshi Ranjha
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, Switzerland
| | - Angelo Taglialatela
- Department of Genetics and Development, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, NY, USA
| | - Alberto Ciccia
- Department of Genetics and Development, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, NY, USA
| | - Petr Cejka
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, Switzerland.,Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), Zürich, Switzerland
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17
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WASp modulates RPA function on single-stranded DNA in response to replication stress and DNA damage. Nat Commun 2022; 13:3743. [PMID: 35768435 PMCID: PMC9243104 DOI: 10.1038/s41467-022-31415-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 06/08/2022] [Indexed: 02/07/2023] Open
Abstract
Perturbation in the replication-stress response (RSR) and DNA-damage response (DDR) causes genomic instability. Genomic instability occurs in Wiskott-Aldrich syndrome (WAS), a primary immunodeficiency disorder, yet the mechanism remains largely uncharacterized. Replication protein A (RPA), a single-strand DNA (ssDNA) binding protein, has key roles in the RSR and DDR. Here we show that human WAS-protein (WASp) modulates RPA functions at perturbed replication forks (RFs). Following genotoxic insult, WASp accumulates at RFs, associates with RPA, and promotes RPA:ssDNA complexation. WASp deficiency in human lymphocytes destabilizes RPA:ssDNA-complexes, impairs accumulation of RPA, ATR, ETAA1, and TOPBP1 at genotoxin-perturbed RFs, decreases CHK1 activation, and provokes global RF dysfunction. las17 (yeast WAS-homolog)-deficient S. cerevisiae also show decreased ScRPA accumulation at perturbed RFs, impaired DNA recombination, and increased frequency of DNA double-strand break (DSB)-induced single-strand annealing (SSA). Consequently, WASp (or Las17)-deficient cells show increased frequency of DSBs upon genotoxic insult. Our study reveals an evolutionarily conserved, essential role of WASp in the DNA stress-resolution pathway, such that WASp deficiency provokes RPA dysfunction-coupled genomic instability. Cancer develops in Wiskott-Aldrich syndrome (WAS). Here the authors identify a role for WAS-protein (WASp) in the DNA stress-resolution pathway by promoting the function of Replication Protein A at replication forks after DNA damage.
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18
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Peake JD, Noguchi E. Fanconi anemia: current insights regarding epidemiology, cancer, and DNA repair. Hum Genet 2022; 141:1811-1836. [PMID: 35596788 DOI: 10.1007/s00439-022-02462-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 05/09/2022] [Indexed: 12/12/2022]
Abstract
Fanconi anemia is a genetic disorder that is characterized by bone marrow failure, as well as a predisposition to malignancies including leukemia and squamous cell carcinoma (SCC). At least 22 genes are associated with Fanconi anemia, constituting the Fanconi anemia DNA repair pathway. This pathway coordinates multiple processes and proteins to facilitate the repair of DNA adducts including interstrand crosslinks (ICLs) that are generated by environmental carcinogens, chemotherapeutic crosslinkers, and metabolic products of alcohol. ICLs can interfere with DNA transactions, including replication and transcription. If not properly removed and repaired, ICLs cause DNA breaks and lead to genomic instability, a hallmark of cancer. In this review, we will discuss the genetic and phenotypic characteristics of Fanconi anemia, the epidemiology of the disease, and associated cancer risk. The sources of ICLs and the role of ICL-inducing chemotherapeutic agents will also be discussed. Finally, we will review the detailed mechanisms of ICL repair via the Fanconi anemia DNA repair pathway, highlighting critical regulatory processes. Together, the information in this review will underscore important contributions to Fanconi anemia research in the past two decades.
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Affiliation(s)
- Jasmine D Peake
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA, 19102, USA
| | - Eishi Noguchi
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA, 19102, USA.
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19
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Division of Labor by the HELQ, BLM, and FANCM Helicases during Homologous Recombination Repair in Drosophila melanogaster. Genes (Basel) 2022; 13:genes13030474. [PMID: 35328029 PMCID: PMC8951532 DOI: 10.3390/genes13030474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/02/2022] [Accepted: 03/07/2022] [Indexed: 02/01/2023] Open
Abstract
Repair of DNA double-strand breaks by homologous recombination (HR) requires a carefully orchestrated sequence of events involving many proteins. One type of HR, synthesis-dependent strand annealing (SDSA), proceeds via the formation of a displacement loop (D-loop) when RAD51-coated single-stranded DNA invades a homologous template. The 3' end of the single-stranded DNA is extended by DNA synthesis. In SDSA, the D-loop is then disassembled prior to strand annealing. While many helicases can unwind D-loops in vitro, how their action is choreographed in vivo remains to be determined. To clarify the roles of various DNA helicases during SDSA, we used a double-strand gap repair assay to study the outcomes of homologous recombination repair in Drosophila melanogaster lacking the BLM, HELQ, and FANCM helicases. We found that the absence of any of these three helicases impairs gap repair. In addition, flies lacking both BLM and HELQ or HELQ and FANCM had more severe SDSA defects than the corresponding single mutants. In the absence of BLM, a large percentage of repair events were accompanied by flanking deletions. Strikingly, these deletions were mostly abolished in the blm helq and blm fancm double mutants. Our results suggest that the BLM, HELQ, and FANCM helicases play distinct roles during SDSA, with HELQ and FANCM acting early to promote the formation of recombination intermediates that are then processed by BLM to prevent repair by deletion-prone mechanisms.
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20
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Ler AAL, Carty MP. DNA Damage Tolerance Pathways in Human Cells: A Potential Therapeutic Target. Front Oncol 2022; 11:822500. [PMID: 35198436 PMCID: PMC8859465 DOI: 10.3389/fonc.2021.822500] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 12/30/2021] [Indexed: 12/26/2022] Open
Abstract
DNA lesions arising from both exogenous and endogenous sources occur frequently in DNA. During DNA replication, the presence of unrepaired DNA damage in the template can arrest replication fork progression, leading to fork collapse, double-strand break formation, and to genome instability. To facilitate completion of replication and prevent the generation of strand breaks, DNA damage tolerance (DDT) pathways play a key role in allowing replication to proceed in the presence of lesions in the template. The two main DDT pathways are translesion synthesis (TLS), which involves the recruitment of specialized TLS polymerases to the site of replication arrest to bypass lesions, and homology-directed damage tolerance, which includes the template switching and fork reversal pathways. With some exceptions, lesion bypass by TLS polymerases is a source of mutagenesis, potentially contributing to the development of cancer. The capacity of TLS polymerases to bypass replication-blocking lesions induced by anti-cancer drugs such as cisplatin can also contribute to tumor chemoresistance. On the other hand, during homology-directed DDT the nascent sister strand is transiently utilised as a template for replication, allowing for error-free lesion bypass. Given the role of DNA damage tolerance pathways in replication, mutagenesis and chemoresistance, a more complete understanding of these pathways can provide avenues for therapeutic exploitation. A number of small molecule inhibitors of TLS polymerase activity have been identified that show synergy with conventional chemotherapeutic agents in killing cancer cells. In this review, we will summarize the major DDT pathways, explore the relationship between damage tolerance and carcinogenesis, and discuss the potential of targeting TLS polymerases as a therapeutic approach.
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Affiliation(s)
- Ashlynn Ai Li Ler
- Biochemistry, School of Biological and Chemical Sciences, The National University of Ireland (NUI) Galway, Galway, Ireland
| | - Michael P. Carty
- Biochemistry, School of Biological and Chemical Sciences, The National University of Ireland (NUI) Galway, Galway, Ireland
- DNA Damage Response Laboratory, Centre for Chromosome Biology, NUI Galway, Galway, Ireland
- *Correspondence: Michael P. Carty,
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21
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Balbo Pogliano C, Ceppi I, Giovannini S, Petroulaki V, Palmer N, Uliana F, Gatti M, Kasaciunaite K, Freire R, Seidel R, Altmeyer M, Cejka P, Matos J. The CDK1-TOPBP1-PLK1 axis regulates the Bloom's syndrome helicase BLM to suppress crossover recombination in somatic cells. SCIENCE ADVANCES 2022; 8:eabk0221. [PMID: 35119917 PMCID: PMC8816346 DOI: 10.1126/sciadv.abk0221] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 12/14/2021] [Indexed: 06/14/2023]
Abstract
Bloom's syndrome is caused by inactivation of the BLM helicase, which functions with TOP3A and RMI1-2 (BTR complex) to dissolve recombination intermediates and avoid somatic crossing-over. We show here that crossover avoidance by BTR further requires the activity of cyclin-dependent kinase-1 (CDK1), Polo-like kinase-1 (PLK1), and the DDR mediator protein TOPBP1, which act in the same pathway. Mechanistically, CDK1 phosphorylates BLM and TOPBP1 and promotes the interaction of both proteins with PLK1. This is amplified by the ability of TOPBP1 to facilitate phosphorylation of BLM at sites that stimulate both BLM-PLK1 and BLM-TOPBP1 binding, creating a positive feedback loop that drives rapid BLM phosphorylation at the G2-M transition. In vitro, BLM phosphorylation by CDK/PLK1/TOPBP1 stimulates the dissolution of topologically linked DNA intermediates by BLM-TOP3A. Thus, we propose that the CDK1-TOPBP1-PLK1 axis enhances BTR-mediated dissolution of recombination intermediates late in the cell cycle to suppress crossover recombination and curtail genomic instability.
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Affiliation(s)
| | - Ilaria Ceppi
- Institute for Research in Biomedicine, Faculty of Biomedical Sciences, Università della Svizzera italiana (USI), 6500 Bellinzona, Switzerland
| | - Sara Giovannini
- Institute of Biochemistry, ETH Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
| | - Vasiliki Petroulaki
- Department of Chromosome Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter, Vienna, Austria
| | - Nathan Palmer
- Department of Chromosome Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter, Vienna, Austria
| | - Federico Uliana
- Institute of Biochemistry, ETH Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
| | - Marco Gatti
- Department of Molecular Mechanisms of Disease, University of Zurich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Kristina Kasaciunaite
- Peter Debye Institute for Soft Matter Physics, Universität Leipzig, 04103 Leipzig, Germany
| | - Raimundo Freire
- Unidad de Investigación, Hospital Universitario de Canarias–FIISC, Ofra s/n, 38320 La Laguna, Tenerife, Spain
- Instituto de Tecnologías Biomédicas, Universidad de La Laguna, Tenerife, Spain
- Universidad Fernando Pessoa Canarias, 35450 Las Palmas de Gran Canaria, Spain
| | - Ralf Seidel
- Peter Debye Institute for Soft Matter Physics, Universität Leipzig, 04103 Leipzig, Germany
| | - Matthias Altmeyer
- Department of Molecular Mechanisms of Disease, University of Zurich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Petr Cejka
- Institute of Biochemistry, ETH Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
- Institute for Research in Biomedicine, Faculty of Biomedical Sciences, Università della Svizzera italiana (USI), 6500 Bellinzona, Switzerland
| | - Joao Matos
- Institute of Biochemistry, ETH Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
- Department of Chromosome Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter, Vienna, Austria
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22
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Adeyemi RO, Willis NA, Elia AEH, Clairmont C, Li S, Wu X, D'Andrea AD, Scully R, Elledge SJ. The Protexin complex counters resection on stalled forks to promote homologous recombination and crosslink repair. Mol Cell 2021; 81:4440-4456.e7. [PMID: 34597596 PMCID: PMC8588999 DOI: 10.1016/j.molcel.2021.09.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 07/11/2021] [Accepted: 09/07/2021] [Indexed: 02/06/2023]
Abstract
Protection of stalled replication forks is critical to genomic stability. Using genetic and proteomic analyses, we discovered the Protexin complex containing the ssDNA binding protein SCAI and the DNA polymerase REV3. Protexin is required specifically for protecting forks stalled by nucleotide depletion, fork barriers, fragile sites, and DNA inter-strand crosslinks (ICLs), where it promotes homologous recombination and repair. Protexin loss leads to ssDNA accumulation and profound genomic instability in response to ICLs. Protexin interacts with RNA POL2, and both oppose EXO1's resection of DNA on forks remodeled by the FANCM translocase activity. This pathway acts independently of BRCA/RAD51-mediated fork stabilization, and cells with BRCA2 mutations were dependent on SCAI for survival. These data suggest that Protexin and its associated factors establish a new fork protection pathway that counteracts fork resection in part through a REV3 polymerase-dependent resynthesis mechanism of excised DNA, particularly at ICL stalled forks.
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Affiliation(s)
- Richard O Adeyemi
- Department of Genetics, Harvard Medical School, and Division of Genetics, Brigham and Women's Hospital, Howard Hughes Medical Institute, Boston, MA 02115, USA
| | - Nicholas A Willis
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Andrew E H Elia
- Department of Genetics, Harvard Medical School, and Division of Genetics, Brigham and Women's Hospital, Howard Hughes Medical Institute, Boston, MA 02115, USA
| | - Connor Clairmont
- Department of Radiation Oncology and Center for DNA Damage and Repair, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Shibo Li
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Xiaohua Wu
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Alan D D'Andrea
- Department of Radiation Oncology and Center for DNA Damage and Repair, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Ralph Scully
- Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Stephen J Elledge
- Department of Genetics, Harvard Medical School, and Division of Genetics, Brigham and Women's Hospital, Howard Hughes Medical Institute, Boston, MA 02115, USA.
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23
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Ninou AH, Lehto J, Chioureas D, Stigsdotter H, Schelzig K, Åkerlund E, Gudoityte G, Joneborg U, Carlson J, Jonkers J, Seashore-Ludlow B, Gustafsson NMS. PFKFB3 Inhibition Sensitizes DNA Crosslinking Chemotherapies by Suppressing Fanconi Anemia Repair. Cancers (Basel) 2021; 13:cancers13143604. [PMID: 34298817 PMCID: PMC8306909 DOI: 10.3390/cancers13143604] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/13/2021] [Accepted: 07/15/2021] [Indexed: 12/25/2022] Open
Abstract
Simple Summary DNA-damaging chemotherapeutics, such as platinum drugs, are cornerstones in cancer treatment. The efficacy of such treatment is intimately linked to the DNA repair capacity of the cancer cells, as DNA damage above a tolerable threshold culminates in cell death. Cancer cells often have deregulated DNA repair mechanisms, making them initially more sensitive to DNA-damaging chemotherapies. Unfortunately, over time, cancer cells often develop resistance to such treatments by rewiring their DNA damage response pathways. Here, we identify that targeting the recognized anti-cancer target 6-phosphofructo-2-kinase/fructose-2,6,-bisphophatase 3 (PFKFB3), commonly overexpressed in cancer, with the small molecule inhibitor KAN0438757, selectively sensitizes cancer cells to platinum drugs, including treatment-resistant cancer cells, while sparing normal cells. Mechanistically, PFKFB3 promotes tolerance to and the repair of platinum-induced DNA interstrand crosslinks (ICLs) through modulation of the Fanconi anemia (FA) DNA repair pathway. Thus targeting PFKFB3 opens up therapeutic possibilities to improve the efficacy of ICL-inducing cancer treatments. Abstract Replicative repair of interstrand crosslinks (ICL) generated by platinum chemotherapeutics is orchestrated by the Fanconi anemia (FA) repair pathway to ensure resolution of stalled replication forks and the maintenance of genomic integrity. Here, we identify novel regulation of FA repair by the cancer-associated glycolytic enzyme PFKFB3 that has functional consequences for replication-associated ICL repair and cancer cell survival. Inhibition of PFKFB3 displays a cancer-specific synergy with platinum compounds in blocking cell viability and restores sensitivity in treatment-resistant models. Notably, the synergies are associated with DNA-damage-induced chromatin association of PFKFB3 upon cancer transformation, which further increases upon platinum resistance. FA pathway activation triggers the PFKFB3 assembly into nuclear foci in an ATR- and FANCM-dependent manner. Blocking PFKFB3 activity disrupts the assembly of key FA repair factors and consequently prevents fork restart. This results in an incapacity to replicate cells to progress through S-phase, an accumulation of DNA damage in replicating cells, and fork collapse. We further validate PFKFB3-dependent regulation of FA repair in ex vivo cultures from cancer patients. Collectively, targeting PFKFB3 opens up therapeutic possibilities to improve the efficacy of ICL-inducing cancer treatments.
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Affiliation(s)
- Anna Huguet Ninou
- Science for Life Laboratory, Department of Oncology and Pathology, Karolinska Institutet, 171 21 Stockholm, Sweden; (A.H.N.); (J.L.); (D.C.); (H.S.); (K.S.); (E.Å.); (G.G.); (B.S.-L.)
- Kancera AB, Karolinska Science Park, 171 48 Solna, Sweden
| | - Jemina Lehto
- Science for Life Laboratory, Department of Oncology and Pathology, Karolinska Institutet, 171 21 Stockholm, Sweden; (A.H.N.); (J.L.); (D.C.); (H.S.); (K.S.); (E.Å.); (G.G.); (B.S.-L.)
- Kancera AB, Karolinska Science Park, 171 48 Solna, Sweden
| | - Dimitrios Chioureas
- Science for Life Laboratory, Department of Oncology and Pathology, Karolinska Institutet, 171 21 Stockholm, Sweden; (A.H.N.); (J.L.); (D.C.); (H.S.); (K.S.); (E.Å.); (G.G.); (B.S.-L.)
| | - Hannah Stigsdotter
- Science for Life Laboratory, Department of Oncology and Pathology, Karolinska Institutet, 171 21 Stockholm, Sweden; (A.H.N.); (J.L.); (D.C.); (H.S.); (K.S.); (E.Å.); (G.G.); (B.S.-L.)
| | - Korbinian Schelzig
- Science for Life Laboratory, Department of Oncology and Pathology, Karolinska Institutet, 171 21 Stockholm, Sweden; (A.H.N.); (J.L.); (D.C.); (H.S.); (K.S.); (E.Å.); (G.G.); (B.S.-L.)
| | - Emma Åkerlund
- Science for Life Laboratory, Department of Oncology and Pathology, Karolinska Institutet, 171 21 Stockholm, Sweden; (A.H.N.); (J.L.); (D.C.); (H.S.); (K.S.); (E.Å.); (G.G.); (B.S.-L.)
| | - Greta Gudoityte
- Science for Life Laboratory, Department of Oncology and Pathology, Karolinska Institutet, 171 21 Stockholm, Sweden; (A.H.N.); (J.L.); (D.C.); (H.S.); (K.S.); (E.Å.); (G.G.); (B.S.-L.)
| | - Ulrika Joneborg
- Department of Women’s and Children’s Health, Karolinska Institutet, 171 21 Stockholm, Sweden;
| | - Joseph Carlson
- Department of Oncology and Pathology, Karolinska Institutet, 171 76 Stockholm, Sweden;
- Department of Pathology and Laboratory Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Jos Jonkers
- Oncode Institute and Division of Molecular Pathology, The Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands;
| | - Brinton Seashore-Ludlow
- Science for Life Laboratory, Department of Oncology and Pathology, Karolinska Institutet, 171 21 Stockholm, Sweden; (A.H.N.); (J.L.); (D.C.); (H.S.); (K.S.); (E.Å.); (G.G.); (B.S.-L.)
| | - Nina Marie Susanne Gustafsson
- Science for Life Laboratory, Department of Oncology and Pathology, Karolinska Institutet, 171 21 Stockholm, Sweden; (A.H.N.); (J.L.); (D.C.); (H.S.); (K.S.); (E.Å.); (G.G.); (B.S.-L.)
- Correspondence:
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24
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Abstract
DNA interstrand cross-links (ICLs) covalently connect the two strands of the double helix and are extremely cytotoxic. Defective ICL repair causes the bone marrow failure and cancer predisposition syndrome, Fanconi anemia, and upregulation of repair causes chemotherapy resistance in cancer. The central event in ICL repair involves resolving the cross-link (unhooking). In this review, we discuss the chemical diversity of ICLs generated by exogenous and endogenous agents. We then describe how proliferating and nonproliferating vertebrate cells unhook ICLs. We emphasize fundamentally new unhooking strategies, dramatic progress in the structural analysis of the Fanconi anemia pathway, and insights into how cells govern the choice between different ICL repair pathways. Throughout, we highlight the many gaps that remain in our knowledge of these fascinating DNA repair pathways.
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Affiliation(s)
- Daniel R Semlow
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA; .,Current affiliation: Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Johannes C Walter
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA; .,Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
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25
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Panday A, Willis NA, Elango R, Menghi F, Duffey EE, Liu ET, Scully R. FANCM regulates repair pathway choice at stalled replication forks. Mol Cell 2021; 81:2428-2444.e6. [PMID: 33882298 DOI: 10.1016/j.molcel.2021.03.044] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 02/18/2021] [Accepted: 03/26/2021] [Indexed: 01/19/2023]
Abstract
Repair pathway "choice" at stalled mammalian replication forks is an important determinant of genome stability; however, the underlying mechanisms are poorly understood. FANCM encodes a multi-domain scaffolding and motor protein that interacts with several distinct repair protein complexes at stalled forks. Here, we use defined mutations engineered within endogenous Fancm in mouse embryonic stem cells to study how Fancm regulates stalled fork repair. We find that distinct FANCM repair functions are enacted by molecularly separable scaffolding domains. These findings define FANCM as a key mediator of repair pathway choice at stalled replication forks and reveal its molecular mechanism. Notably, mutations that inactivate FANCM ATPase function disable all its repair functions and "trap" FANCM at stalled forks. We find that Brca1 hypomorphic mutants are synthetic lethal with Fancm null or Fancm ATPase-defective mutants. The ATPase function of FANCM may therefore represent a promising "druggable" target for therapy of BRCA1-linked cancer.
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Affiliation(s)
- Arvind Panday
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA 02215, USA
| | - Nicholas A Willis
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA 02215, USA
| | - Rajula Elango
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA 02215, USA
| | - Francesca Menghi
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06030, USA
| | - Erin E Duffey
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA 02215, USA
| | - Edison T Liu
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06030, USA
| | - Ralph Scully
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA 02215, USA.
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26
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Bythell-Douglas R, Deans AJ. A Structural Guide to the Bloom Syndrome Complex. Structure 2020; 29:99-113. [PMID: 33357470 DOI: 10.1016/j.str.2020.11.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 09/03/2020] [Accepted: 11/25/2020] [Indexed: 01/19/2023]
Abstract
The Bloom syndrome complex is a DNA damage repair machine. It consists of several protein components which are functional in isolation, but interdependent in cells for the maintenance of accurate homologous recombination. Mutations to any of the genes encoding these proteins cause numerous physical and developmental markers as well as phenotypes of genome instability, infertility, and cancer predisposition. Here we review the published structural and biochemical data on each of the components of the complex: the helicase BLM, the type IA topoisomerase TOP3A, and the OB-fold-containing RMI and RPA subunits. We describe how each component contributes to function, interacts with each other, and the DNA that it manipulates/repairs.
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Affiliation(s)
- Rohan Bythell-Douglas
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, 3056, Australia.
| | - Andrew J Deans
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, 3056, Australia; Department of Medicine (St Vincent's), University of Melbourne, Fitzroy, VIC, 3056, Australia.
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27
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Dhar S, Datta A, Brosh RM. DNA helicases and their roles in cancer. DNA Repair (Amst) 2020; 96:102994. [PMID: 33137625 DOI: 10.1016/j.dnarep.2020.102994] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 09/28/2020] [Indexed: 12/15/2022]
Abstract
DNA helicases, known for their fundamentally important roles in genomic stability, are high profile players in cancer. Not only are there monogenic helicase disorders with a strong disposition to cancer, it is well appreciated that helicase variants are associated with specific cancers (e.g., breast cancer). Flipping the coin, DNA helicases are frequently overexpressed in cancerous tissues and reduction in helicase gene expression results in reduced proliferation and growth capacity, as well as DNA damage induction and apoptosis of cancer cells. The seminal roles of helicases in the DNA damage and replication stress responses, as well as DNA repair pathways, validate their vital importance in cancer biology and suggest their potential values as targets in anti-cancer therapy. In recent years, many laboratories have characterized the specialized roles of helicase to resolve transcription-replication conflicts, maintain telomeres, mediate cell cycle checkpoints, remodel stalled replication forks, and regulate transcription. In vivo models, particularly mice, have been used to interrogate helicase function and serve as a bridge for preclinical studies that may lead to novel therapeutic approaches. In this review, we will summarize our current knowledge of DNA helicases and their roles in cancer, emphasizing the latest developments.
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Affiliation(s)
- Srijita Dhar
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Arindam Datta
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Robert M Brosh
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA.
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28
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Tan W, Deans AJ. The ubiquitination machinery of the Fanconi Anemia DNA repair pathway. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2020; 163:5-13. [PMID: 33058944 DOI: 10.1016/j.pbiomolbio.2020.09.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/25/2020] [Accepted: 09/29/2020] [Indexed: 10/23/2022]
Abstract
The Fanconi Anemia (FA) pathway maintains genome stability by preventing DNA damage from occurring when replication is blocked. Central to the FA pathway is the monoubiquitination of FANCI-FANCD2 mediated by a ubiquitin RING-E3 ligase complex called the FA core complex. Genetic mutation in any component of the FA core complex results in defective FANCI-FANCD2 monoubiquitination and phenotypes of DNA damage sensitivity, birth defects, early-onset bone marrow failure and cancer. Here, we discuss the mechanisms of the FA core complex and FANCI-FANCD2 monoubiquitination at sites of blocked replication and review our current understanding of the biological functions of these proteins in replication fork protection.
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Affiliation(s)
- Winnie Tan
- Genome Stability Unit, St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria, 3065, Australia
| | - Andrew J Deans
- Genome Stability Unit, St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria, 3065, Australia; Department of Medicine, St. Vincent's Health, The University of Melbourne, Australia. https://twitter.com/GenomeStability
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29
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Canonical and Noncanonical Roles of Fanconi Anemia Proteins: Implications in Cancer Predisposition. Cancers (Basel) 2020; 12:cancers12092684. [PMID: 32962238 PMCID: PMC7565043 DOI: 10.3390/cancers12092684] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/11/2020] [Accepted: 09/17/2020] [Indexed: 12/14/2022] Open
Abstract
Simple Summary Fanconi anemia (FA) is a genetic disorder that is characterized by bone marrow failure (BMF), developmental abnormalities, and predisposition to cancer. In this review, we present an overview of both canonical (regulation of interstrand cross-links repair, ICLs) and noncanonical roles of FA proteins. We divide noncanonical alternative functions in two types: nuclear (outside ICLs such as FA action in replication stress or DSB repair) and cytosolic (such as in mitochondrial quality control or selective autophagy). We further discuss the involvement of FA genes in the predisposition to develop different types of cancers and we examine current DNA damage response-targeted therapies. Finally, we promote an insightful perspective regarding the clinical implication of the cytosolic noncanonical roles of FA proteins in cancer predisposition, suggesting that these alternative roles could be of critical importance for disease progression. Abstract Fanconi anemia (FA) is a clinically and genetically heterogeneous disorder characterized by the variable presence of congenital somatic abnormalities, bone marrow failure (BMF), and a predisposition to develop cancer. Monoallelic germline mutations in at least five genes involved in the FA pathway are associated with the development of sporadic hematological and solid malignancies. The key function of the FA pathway is to orchestrate proteins involved in the repair of interstrand cross-links (ICLs), to prevent genomic instability and replication stress. Recently, many studies have highlighted the importance of FA genes in noncanonical pathways, such as mitochondria homeostasis, inflammation, and virophagy, which act, in some cases, independently of DNA repair processes. Thus, primary defects in DNA repair mechanisms of FA patients are typically exacerbated by an impairment of other cytoprotective pathways that contribute to the multifaceted clinical phenotype of this disease. In this review, we summarize recent advances in the understanding of the pathogenesis of FA, with a focus on the cytosolic noncanonical roles of FA genes, discussing how they may contribute to cancer development, thus suggesting opportunities to envisage novel therapeutic approaches.
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30
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Finardi A, Massari LF, Visintin R. Anaphase Bridges: Not All Natural Fibers Are Healthy. Genes (Basel) 2020; 11:genes11080902. [PMID: 32784550 PMCID: PMC7464157 DOI: 10.3390/genes11080902] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/04/2020] [Accepted: 08/05/2020] [Indexed: 02/07/2023] Open
Abstract
At each round of cell division, the DNA must be correctly duplicated and distributed between the two daughter cells to maintain genome identity. In order to achieve proper chromosome replication and segregation, sister chromatids must be recognized as such and kept together until their separation. This process of cohesion is mainly achieved through proteinaceous linkages of cohesin complexes, which are loaded on the sister chromatids as they are generated during S phase. Cohesion between sister chromatids must be fully removed at anaphase to allow chromosome segregation. Other (non-proteinaceous) sources of cohesion between sister chromatids consist of DNA linkages or sister chromatid intertwines. DNA linkages are a natural consequence of DNA replication, but must be timely resolved before chromosome segregation to avoid the arising of DNA lesions and genome instability, a hallmark of cancer development. As complete resolution of sister chromatid intertwines only occurs during chromosome segregation, it is not clear whether DNA linkages that persist in mitosis are simply an unwanted leftover or whether they have a functional role. In this review, we provide an overview of DNA linkages between sister chromatids, from their origin to their resolution, and we discuss the consequences of a failure in their detection and processing and speculate on their potential role.
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Affiliation(s)
- Alice Finardi
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, 20139 Milan, Italy;
| | - Lucia F. Massari
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK;
| | - Rosella Visintin
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, 20139 Milan, Italy;
- Correspondence: ; Tel.: +39-02-5748-9859; Fax: +39-02-9437-5991
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31
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The FANC/BRCA Pathway Releases Replication Blockades by Eliminating DNA Interstrand Cross-Links. Genes (Basel) 2020; 11:genes11050585. [PMID: 32466131 PMCID: PMC7288313 DOI: 10.3390/genes11050585] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/14/2020] [Accepted: 05/21/2020] [Indexed: 12/24/2022] Open
Abstract
DNA interstrand cross-links (ICLs) represent a major barrier blocking DNA replication fork progression. ICL accumulation results in growth arrest and cell death—particularly in cell populations undergoing high replicative activity, such as cancer and leukemic cells. For this reason, agents able to induce DNA ICLs are widely used as chemotherapeutic drugs. However, ICLs are also generated in cells as byproducts of normal metabolic activities. Therefore, every cell must be capable of rescuing lCL-stalled replication forks while maintaining the genetic stability of the daughter cells in order to survive, replicate DNA and segregate chromosomes at mitosis. Inactivation of the Fanconi anemia/breast cancer-associated (FANC/BRCA) pathway by inherited mutations leads to Fanconi anemia (FA), a rare developmental, cancer-predisposing and chromosome-fragility syndrome. FANC/BRCA is the key hub for a complex and wide network of proteins that—upon rescuing ICL-stalled DNA replication forks—allows cell survival. Understanding how cells cope with ICLs is mandatory to ameliorate ICL-based anticancer therapies and provide the molecular basis to prevent or bypass cancer drug resistance. Here, we review our state-of-the-art understanding of the mechanisms involved in ICL resolution during DNA synthesis, with a major focus on how the FANC/BRCA pathway ensures DNA strand opening and prevents genomic instability.
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32
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Jain CK, Mukhopadhyay S, Ganguly A. RecQ Family Helicases in Replication Fork Remodeling and Repair: Opening New Avenues towards the Identification of Potential Targets for Cancer Chemotherapy. Anticancer Agents Med Chem 2020; 20:1311-1326. [PMID: 32418530 DOI: 10.2174/1871520620666200518082433] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 08/08/2019] [Accepted: 12/30/2019] [Indexed: 11/22/2022]
Abstract
Replication fork reversal and restart has gained immense interest as a central response mechanism to replication stress following DNA damage. Although the exact mechanism of fork reversal has not been elucidated precisely, the involvement of diverse pathways and different factors has been demonstrated, which are central to this phenomenon. RecQ helicases known for their vital role in DNA repair and maintaining genome stability has recently been implicated in the restart of regressed replication forks. Through interaction with vital proteins like Poly (ADP) ribose polymerase 1 (PARP1), these helicases participate in the replication fork reversal and restart phenomenon. Most therapeutic agents used for cancer chemotherapy act by causing DNA damage in replicating cells and subsequent cell death. These DNA damages can be repaired by mechanisms involving fork reversal as the key phenomenon eventually reducing the efficacy of the therapeutic agent. Hence the factors contributing to this repair process can be good selective targets for developing more efficient chemotherapeutic agents. In this review, we have discussed in detail the role of various proteins in replication fork reversal and restart with special emphasis on RecQ helicases. Involvement of other proteins like PARP1, recombinase rad51, SWI/SNF complex has also been discussed. Since RecQ helicases play a central role in the DNA damage response following chemotherapeutic treatment, we propose that targeting these helicases can emerge as an alternative to available intervention strategies. We have also summarized the current research status of available RecQ inhibitors and siRNA based therapeutic approaches that targets RecQ helicases. In summary, our review gives an overview of the DNA damage responses involving replication fork reversal and provides new directions for the development of more efficient and sustainable chemotherapeutic approaches.
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Affiliation(s)
- Chetan K Jain
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India
| | - Swagata Mukhopadhyay
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India
| | - Agneyo Ganguly
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India
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33
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Sandhu R, Monge Neria F, Monge Neria J, Chen X, Hollingsworth NM, Börner GV. DNA Helicase Mph1 FANCM Ensures Meiotic Recombination between Parental Chromosomes by Dissociating Precocious Displacement Loops. Dev Cell 2020; 53:458-472.e5. [PMID: 32386601 PMCID: PMC7386354 DOI: 10.1016/j.devcel.2020.04.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 02/09/2020] [Accepted: 04/10/2020] [Indexed: 02/07/2023]
Abstract
Meiotic pairing between parental chromosomes (homologs) is required for formation of haploid gametes. Homolog pairing depends on recombination initiation via programmed double-strand breaks (DSBs). Although DSBs appear prior to pairing, the homolog, rather than the sister chromatid, is used as repair partner for crossing over. Here, we show that Mph1, the budding yeast ortholog of Fanconi anemia helicase FANCM, prevents precocious DSB strand exchange between sister chromatids before homologs have completed pairing. By dissociating precocious DNA displacement loops (D-loops) between sister chromatids, Mph1FANCM ensures high levels of crossovers and non-crossovers between homologs. Later-occurring recombination events are protected from Mph1-mediated dissociation by synapsis protein Zip1. Increased intersister repair in absence of Mph1 triggers a shift among remaining interhomolog events from non-crossovers to crossover-specific strand exchange, explaining Mph1's apparent anti-crossover function. Our findings identify temporal coordination between DSB strand exchange and homolog pairing as a critical determinant for recombination outcome.
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Affiliation(s)
- Rima Sandhu
- Center for Gene Regulation in Health and Disease and Department of Biological Sciences, Cleveland State University, Cleveland, OH 44115, USA
| | - Francisco Monge Neria
- Center for Gene Regulation in Health and Disease and Department of Biological Sciences, Cleveland State University, Cleveland, OH 44115, USA
| | - Jesús Monge Neria
- Center for Gene Regulation in Health and Disease and Department of Biological Sciences, Cleveland State University, Cleveland, OH 44115, USA
| | - Xiangyu Chen
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Nancy M Hollingsworth
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - G Valentin Börner
- Center for Gene Regulation in Health and Disease and Department of Biological Sciences, Cleveland State University, Cleveland, OH 44115, USA; Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106, USA; Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
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34
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O'Rourke JJ, Bythell-Douglas R, Dunn EA, Deans AJ. ALT control, delete: FANCM as an anti-cancer target in Alternative Lengthening of Telomeres. Nucleus 2020; 10:221-230. [PMID: 31663812 PMCID: PMC6949022 DOI: 10.1080/19491034.2019.1685246] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Break-induced replication is a specific type of DNA repair that has a co-opted role in telomere extension by telomerase-negative cancer cells. This Alternative Lengthening of Telomeres (or ‘ALT’) is required for viability in approximately 10% of all carcinomas, but up to 50% of the soft-tissue derived sarcomas. In several recent studies, we and others demonstrate that expression and activity of FANCM, a DNA translocase protein, is essential for the viability of ALT-associated cancers. Here we provide a summary of how and why FANCM depletion leads to deletion of ALT-controlled cancers, predominantly through a hyper-activation of break-induced replication. We also discuss how FANCM can and has been targeted in cancer cell killing, including potential opportunities in ALT and other genetic backgrounds.
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Affiliation(s)
- Julienne J O'Rourke
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, Australia.,Department of Medicine, (St Vincent's) University of Melbourne, Fitzroy, Australia
| | - Rohan Bythell-Douglas
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, Australia
| | - Elyse A Dunn
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, Australia
| | - Andrew J Deans
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, Australia.,Department of Medicine, (St Vincent's) University of Melbourne, Fitzroy, Australia
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35
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Huselid E, Bunting SF. The Regulation of Homologous Recombination by Helicases. Genes (Basel) 2020; 11:genes11050498. [PMID: 32369918 PMCID: PMC7290689 DOI: 10.3390/genes11050498] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 04/29/2020] [Accepted: 04/29/2020] [Indexed: 11/16/2022] Open
Abstract
Homologous recombination is essential for DNA repair, replication and the exchange of genetic material between parental chromosomes during meiosis. The stages of recombination involve complex reorganization of DNA structures, and the successful completion of these steps is dependent on the activities of multiple helicase enzymes. Helicases of many different families coordinate the processing of broken DNA ends, and the subsequent formation and disassembly of the recombination intermediates that are necessary for template-based DNA repair. Loss of recombination-associated helicase activities can therefore lead to genomic instability, cell death and increased risk of tumor formation. The efficiency of recombination is also influenced by the ‘anti-recombinase’ effect of certain helicases, which can direct DNA breaks toward repair by other pathways. Other helicases regulate the crossover versus non-crossover outcomes of repair. The use of recombination is increased when replication forks and the transcription machinery collide, or encounter lesions in the DNA template. Successful completion of recombination in these situations is also regulated by helicases, allowing normal cell growth, and the maintenance of genomic integrity.
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36
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Abstract
Common fragile sites (CFSs) are large chromosomal regions that exhibit breakage on metaphase chromosomes upon replication stress. They become preferentially unstable at the early stage of cancer development and are hotspots for chromosomal rearrangements in cancers. Increasing evidence has highlighted the complexity underlying the instability of CFSs, and a combination of multiple mechanisms is believed to cause CFS fragility. We will review recent advancements in our understanding of the molecular mechanisms underlying the maintenance of CFS stability and the relevance of CFSs to cancer-associated genome instability. We will emphasize the contribution of the structure-prone AT-rich sequences to CFS instability, which is in line with the recent genome-wide study showing that structure-forming repeat sequences are principal sites of replication stress.
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Affiliation(s)
- Shibo Li
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, San Diego, CA 92037 USA
| | - Xiaohua Wu
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, San Diego, CA 92037 USA
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37
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Brosh RM, Matson SW. History of DNA Helicases. Genes (Basel) 2020; 11:genes11030255. [PMID: 32120966 PMCID: PMC7140857 DOI: 10.3390/genes11030255] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 02/18/2020] [Accepted: 02/20/2020] [Indexed: 12/13/2022] Open
Abstract
Since the discovery of the DNA double helix, there has been a fascination in understanding the molecular mechanisms and cellular processes that account for: (i) the transmission of genetic information from one generation to the next and (ii) the remarkable stability of the genome. Nucleic acid biologists have endeavored to unravel the mysteries of DNA not only to understand the processes of DNA replication, repair, recombination, and transcription but to also characterize the underlying basis of genetic diseases characterized by chromosomal instability. Perhaps unexpectedly at first, DNA helicases have arisen as a key class of enzymes to study in this latter capacity. From the first discovery of ATP-dependent DNA unwinding enzymes in the mid 1970's to the burgeoning of helicase-dependent pathways found to be prevalent in all kingdoms of life, the story of scientific discovery in helicase research is rich and informative. Over four decades after their discovery, we take this opportunity to provide a history of DNA helicases. No doubt, many chapters are left to be written. Nonetheless, at this juncture we are privileged to share our perspective on the DNA helicase field - where it has been, its current state, and where it is headed.
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Affiliation(s)
- Robert M. Brosh
- Section on DNA Helicases, Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
- Correspondence: (R.M.B.J.); (S.W.M.); Tel.: +1-410-558-8578 (R.M.B.J.); +1-919-962-0005 (S.W.M.)
| | - Steven W. Matson
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Correspondence: (R.M.B.J.); (S.W.M.); Tel.: +1-410-558-8578 (R.M.B.J.); +1-919-962-0005 (S.W.M.)
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RAP80 and BRCA1 PARsylation protect chromosome integrity by preventing retention of BRCA1-B/C complexes in DNA repair foci. Proc Natl Acad Sci U S A 2020; 117:2084-2091. [PMID: 31932421 PMCID: PMC6995001 DOI: 10.1073/pnas.1908003117] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Normally, BRCA1 promotes physiological, error-free homologous recombination repair (HRR) of damaged DNA and genome stability. In contrast, excessive, deregulated HRR can lead to genome instability. The BRCA1-binding protein RAP80 restricts HRR amplitude and genome instability, at least in part by manifesting polyubiquitin and poly-ADP-ribose binding activities in postdamage nuclear foci. Although how these processes operate in detail remains unknown, we find that simultaneous defects in RAP80/BRCA1 complex formation and in BRCA1 poly-ADP-ribosylation result in the persistent accumulation of BRCA1-containing complexes in nuclear foci that also contain CtIP and BACH1. These effects lead to excessive HRR, chromosomal hyper-recombination, and gross chromosomal abnormalities. BRCA1 promotes error-free, homologous recombination-mediated repair (HRR) of DNA double-stranded breaks (DSBs). When excessive and uncontrolled, BRCA1 HRR activity promotes illegitimate recombination and genome disorder. We and others have observed that the BRCA1-associated protein RAP80 recruits BRCA1 to postdamage nuclear foci, and these chromatin structures then restrict the amplitude of BRCA1-driven HRR. What remains unclear is how this process is regulated. Here we report that both BRCA1 poly-ADP ribosylation (PARsylation) and the presence of BRCA1-bound RAP80 are critical for the normal interaction of BRCA1 with some of its partners (e.g., CtIP and BACH1) that are also known components of the aforementioned focal structures. Surprisingly, the simultaneous loss of RAP80 and failure therein of BRCA1 PARsylation results in the dysregulated accumulation in these foci of BRCA1 complexes. This in turn is associated with the intracellular development of a state of hyper-recombination and gross chromosomal disorder. Thus, physiological RAP80-BRCA1 complex formation and BRCA1 PARsylation contribute to the kinetics by which BRCA1 HRR-sustaining complexes normally concentrate in nuclear foci. These events likely contribute to aneuploidy suppression.
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Wong IN, Neo JPS, Oehler J, Schafhauser S, Osman F, Carr SB, Whitby MC. The Fml1-MHF complex suppresses inter-fork strand annealing in fission yeast. eLife 2019; 8:e49784. [PMID: 31855181 PMCID: PMC6952179 DOI: 10.7554/elife.49784] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Accepted: 12/18/2019] [Indexed: 12/30/2022] Open
Abstract
Previously we reported that a process called inter-fork strand annealing (IFSA) causes genomic deletions during the termination of DNA replication when an active replication fork converges on a collapsed fork (Morrow et al., 2017). We also identified the FANCM-related DNA helicase Fml1 as a potential suppressor of IFSA. Here, we confirm that Fml1 does indeed suppress IFSA, and show that this function depends on its catalytic activity and ability to interact with Mhf1-Mhf2 via its C-terminal domain. Finally, a plausible mechanism of IFSA suppression is demonstrated by the finding that Fml1 can catalyse regressed fork restoration in vitro.
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Affiliation(s)
- Io Nam Wong
- Department of BiochemistryUniversity of OxfordOxfordUnited Kingdom
| | | | - Judith Oehler
- Department of BiochemistryUniversity of OxfordOxfordUnited Kingdom
| | | | - Fekret Osman
- Department of BiochemistryUniversity of OxfordOxfordUnited Kingdom
| | - Stephen B Carr
- Research Complex at Harwell, Rutherford Appleton LaboratoryHarwellUnited Kingdom
| | - Matthew C Whitby
- Department of BiochemistryUniversity of OxfordOxfordUnited Kingdom
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FANCM suppresses DNA replication stress at ALT telomeres by disrupting TERRA R-loops. Sci Rep 2019; 9:19110. [PMID: 31836759 PMCID: PMC6911001 DOI: 10.1038/s41598-019-55537-5] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 11/30/2019] [Indexed: 12/03/2022] Open
Abstract
Cancer cells maintain their telomeres by either re-activating telomerase or adopting the homologous recombination (HR)-based Alternative Lengthening of Telomere (ALT) pathway. Among the many prominent features of ALT cells, C-circles (CC) formation is considered to be the most specific and quantifiable biomarker of ALT. However, the molecular mechanism behind the initiation and maintenance of CC formation in ALT cells is still largely unknown. We reported previously that depletion of the FANCM complex (FANCM-FAAP24-MHF1&2) in ALT cells induced pronounced replication stress, which primarily takes place at their telomeres. Here, we characterized the changes in ALT associated phenotypes in cells deficient of the FANCM complex. We found that depletion of FAAP24 or FANCM, but not MHF1&2, induces a dramatic increase of CC formation. Most importantly, we identified multiple DNA damage response (DDR) and DNA repair pathways that stimulate the dramatic increase of CC formation in FANCM deficient cells, including the dissolvase complex (BLM-TOP3A-RMI1/2, or BTR), DNA damage checkpoint kinases (ATR and Chk1), HR proteins (BRCA2, PALB2, and Rad51), as well as proteins involved in Break-Induced Replication (BIR) (POLD1 and POLD3). In addition, FANCD2, another Fanconi Anemia (FA) protein, is also required for CC formation, likely through promoting the recruitment of BLM to the replication stressed ALT telomeres. Finally, we demonstrated that TERRA R-loops accumulate at telomeres in FANCM deficient ALT cells and downregulation of which attenuates the ALT-associated PML bodies (APBs), replication stress and CC formation. Taken together, our data suggest that FANCM prevents replisomes from stalling/collapsing at ALT telomeres by disrupting TERRA R-loops.
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Pilzecker B, Buoninfante OA, Jacobs H. DNA damage tolerance in stem cells, ageing, mutagenesis, disease and cancer therapy. Nucleic Acids Res 2019; 47:7163-7181. [PMID: 31251805 PMCID: PMC6698745 DOI: 10.1093/nar/gkz531] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 05/22/2019] [Accepted: 06/26/2019] [Indexed: 12/12/2022] Open
Abstract
The DNA damage response network guards the stability of the genome from a plethora of exogenous and endogenous insults. An essential feature of the DNA damage response network is its capacity to tolerate DNA damage and structural impediments during DNA synthesis. This capacity, referred to as DNA damage tolerance (DDT), contributes to replication fork progression and stability in the presence of blocking structures or DNA lesions. Defective DDT can lead to a prolonged fork arrest and eventually cumulate in a fork collapse that involves the formation of DNA double strand breaks. Four principal modes of DDT have been distinguished: translesion synthesis, fork reversal, template switching and repriming. All DDT modes warrant continuation of replication through bypassing the fork stalling impediment or repriming downstream of the impediment in combination with filling of the single-stranded DNA gaps. In this way, DDT prevents secondary DNA damage and critically contributes to genome stability and cellular fitness. DDT plays a key role in mutagenesis, stem cell maintenance, ageing and the prevention of cancer. This review provides an overview of the role of DDT in these aspects.
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Affiliation(s)
- Bas Pilzecker
- Division of Tumor Biology and Immunology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Olimpia Alessandra Buoninfante
- Division of Tumor Biology and Immunology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Heinz Jacobs
- Division of Tumor Biology and Immunology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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42
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Wolter F, Puchta H. In planta gene targeting can be enhanced by the use of CRISPR/Cas12a. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 100:1083-1094. [PMID: 31381206 DOI: 10.1111/tpj.14488] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 07/08/2019] [Accepted: 07/29/2019] [Indexed: 05/20/2023]
Abstract
The controlled change of plant genomes by homologous recombination (HR) is still difficult to achieve. We previously developed the in planta gene targeting (ipGT) technology which depends on the simultaneous activation of the target locus by a double-strand break and the excision of the target vector. Whereas the use of SpCas9 resulted in low ipGT frequencies in Arabidopsis, we were recently able to improve the efficiency by using egg cell-specific expression of the potent but less broadly applicable SaCas9 nuclease. In this study, we now tested whether we could improve ipGT further, by either performing it in cells with enhanced intrachromosomal HR efficiencies or by the use of Cas12a, a different kind of CRISPR/Cas nuclease with an alternative cutting mechanism. We could show before that plants possess three kinds of DNA ATPase complexes, which all lead to instabilities of homologous genomic repeats if lost by mutation. As these proteins act in independent pathways, we tested ipGT in double mutants in which intrachromosomal HR is enhanced 20-80-fold. However, we were not able to obtain higher ipGT frequencies, indicating that mechanisms for gene targeting (GT) and chromosomal repeat-induced HR differ. However, using LbCas12a, the GT frequencies were higher than with SaCas9, despite a lower non-homologous end-joining (NHEJ) induction efficiency, demonstrating the particular suitability of Cas12a to induce HR. As SaCas9 has substantial restrictions due to its longer GC rich PAM sequence, the use of LbCas12a with its AT-rich PAM broadens the range of ipGT drastically, particularly when targeting in CG-deserts like promoters and introns.
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Affiliation(s)
- Felix Wolter
- Botanical Institute, Karlsruhe Institute of Technology, POB 6980, 76049, Karlsruhe, Germany
| | - Holger Puchta
- Botanical Institute, Karlsruhe Institute of Technology, POB 6980, 76049, Karlsruhe, Germany
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43
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Mutreja K, Krietsch J, Hess J, Ursich S, Berti M, Roessler FK, Zellweger R, Patra M, Gasser G, Lopes M. ATR-Mediated Global Fork Slowing and Reversal Assist Fork Traverse and Prevent Chromosomal Breakage at DNA Interstrand Cross-Links. Cell Rep 2019; 24:2629-2642.e5. [PMID: 30184498 PMCID: PMC6137818 DOI: 10.1016/j.celrep.2018.08.019] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 07/26/2018] [Accepted: 08/07/2018] [Indexed: 01/02/2023] Open
Abstract
Interstrand cross-links (ICLs) are toxic DNA lesions interfering with DNA metabolism that are induced by widely used anticancer drugs. They have long been considered absolute roadblocks for replication forks, implicating complex DNA repair processes at stalled or converging replication forks. Recent evidence challenged this view, proposing that single forks traverse ICLs by yet elusive mechanisms. Combining ICL immunolabeling and single-molecule approaches in human cells, we now show that ICL induction leads to global replication fork slowing, involving forks not directly challenged by ICLs. Active fork slowing is linked to rapid recruitment of RAD51 to replicating chromatin and to RAD51/ZRANB3-mediated fork reversal. This global modulation of fork speed and architecture requires ATR activation, promotes single-fork ICL traverse—here, directly visualized by electron microscopy—and prevents chromosomal breakage by untimely ICL processing. We propose that global fork slowing by remodeling provides more time for template repair and promotes bypass of residual lesions, limiting fork-associated processing. Fork slowing and reversal are also observed at forks not directly challenged by ICLs Fork reversal assists ICL traverse and limits DSBs associated with ICL unhooking ICL traverse can be directly visualized in human cells by electron microscopy ATR mediates global fork slowing and reversal upon different genotoxic treatments
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Affiliation(s)
- Karun Mutreja
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Jana Krietsch
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Jeannine Hess
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Sebastian Ursich
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Matteo Berti
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Fabienne K Roessler
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Center for Microscopy and Image Analysis, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Ralph Zellweger
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Malay Patra
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Gilles Gasser
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Massimo Lopes
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
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Dattani A, Wilkinson SR. Deciphering the interstrand crosslink DNA repair network expressed by Trypanosoma brucei. DNA Repair (Amst) 2019; 78:154-166. [DOI: 10.1016/j.dnarep.2019.04.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 03/29/2019] [Accepted: 04/24/2019] [Indexed: 10/26/2022]
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45
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Lu R, O'Rourke JJ, Sobinoff AP, Allen JAM, Nelson CB, Tomlinson CG, Lee M, Reddel RR, Deans AJ, Pickett HA. The FANCM-BLM-TOP3A-RMI complex suppresses alternative lengthening of telomeres (ALT). Nat Commun 2019; 10:2252. [PMID: 31138797 PMCID: PMC6538672 DOI: 10.1038/s41467-019-10180-6] [Citation(s) in RCA: 116] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 04/23/2019] [Indexed: 12/21/2022] Open
Abstract
The collapse of stalled replication forks is a major driver of genomic instability. Several committed mechanisms exist to resolve replication stress. These pathways are particularly pertinent at telomeres. Cancer cells that use Alternative Lengthening of Telomeres (ALT) display heightened levels of telomere-specific replication stress, and co-opt stalled replication forks as substrates for break-induced telomere synthesis. FANCM is a DNA translocase that can form independent functional interactions with the BLM-TOP3A-RMI (BTR) complex and the Fanconi anemia (FA) core complex. Here, we demonstrate that FANCM depletion provokes ALT activity, evident by increased break-induced telomere synthesis, and the induction of ALT biomarkers. FANCM-mediated attenuation of ALT requires its inherent DNA translocase activity and interaction with the BTR complex, but does not require the FA core complex, indicative of FANCM functioning to restrain excessive ALT activity by ameliorating replication stress at telomeres. Synthetic inhibition of FANCM-BTR complex formation is selectively toxic to ALT cancer cells.
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Affiliation(s)
- Robert Lu
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, 2145, NSW, Australia
| | - Julienne J O'Rourke
- Genome Stability Unit, St. Vincent's Institute, 9 Princes St, Fitzroy, 3065, VIC, Australia
- Department of Medicine (St. Vincent's), University of Melbourne, Parkville, 3052, VIC, Australia
| | - Alexander P Sobinoff
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, 2145, NSW, Australia
| | - Joshua A M Allen
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, 2145, NSW, Australia
| | - Christopher B Nelson
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, 2145, NSW, Australia
| | - Christopher G Tomlinson
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, 2145, NSW, Australia
| | - Michael Lee
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, 2145, NSW, Australia
| | - Roger R Reddel
- Cancer Research Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, 2145, NSW, Australia
| | - Andrew J Deans
- Genome Stability Unit, St. Vincent's Institute, 9 Princes St, Fitzroy, 3065, VIC, Australia.
- Department of Medicine (St. Vincent's), University of Melbourne, Parkville, 3052, VIC, Australia.
| | - Hilda A Pickett
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, 2145, NSW, Australia.
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Huang J, Zhang J, Bellani MA, Pokharel D, Gichimu J, James RC, Gali H, Ling C, Yan Z, Xu D, Chen J, Meetei AR, Li L, Wang W, Seidman MM. Remodeling of Interstrand Crosslink Proximal Replisomes Is Dependent on ATR, FANCM, and FANCD2. Cell Rep 2019; 27:1794-1808.e5. [PMID: 31067464 PMCID: PMC6676478 DOI: 10.1016/j.celrep.2019.04.032] [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: 12/19/2017] [Revised: 12/19/2018] [Accepted: 04/04/2019] [Indexed: 11/23/2022] Open
Abstract
Eukaryotic replisomes are driven by the mini chromosome maintenance (MCM [M]) helicase complex, an offset ring locked around the template for leading strand synthesis by CDC45 (C) and GINS (G) proteins. Although the CDC45 MCM GINS (CMG) structure implies that interstrand crosslinks (ICLs) are absolute blocks to replisomes, recent studies indicate that cells can restart DNA synthesis on the side of the ICL distal to the initial encounter. Here, we report that restart requires ATR and is promoted by FANCD2 and phosphorylated FANCM. Following introduction of genomic ICLs and dependent on ATR and FANCD2 but not on the Fanconi anemia core proteins or FAAP24, FANCM binds the replisome complex, with concomitant release of the GINS proteins. In situ analysis of replisomes proximal to ICLs confirms the ATR-dependent release of GINS proteins while CDC45 is retained on the remodeled replisome. The results demonstrate the plasticity of CMG composition in response to replication stress.
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Affiliation(s)
- Jing Huang
- Institute of Chemical Biology and Nanomedicine, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, China.
| | - Jing Zhang
- Laboratory of Molecular Gerontology, National Institute on Aging, NIH, 251 Bayview Blvd., Baltimore, MD 21224, USA
| | - Marina A Bellani
- Laboratory of Molecular Gerontology, National Institute on Aging, NIH, 251 Bayview Blvd., Baltimore, MD 21224, USA
| | - Durga Pokharel
- Laboratory of Molecular Gerontology, National Institute on Aging, NIH, 251 Bayview Blvd., Baltimore, MD 21224, USA
| | - Julia Gichimu
- Laboratory of Molecular Gerontology, National Institute on Aging, NIH, 251 Bayview Blvd., Baltimore, MD 21224, USA
| | - Ryan C James
- Laboratory of Molecular Gerontology, National Institute on Aging, NIH, 251 Bayview Blvd., Baltimore, MD 21224, USA
| | - Himabindu Gali
- Department of Pharmacology & Experimental Therapeutics and Medicine, Boston University School of Medicine, 72 East Concord St., K-712D, Boston, MA 02118-2526
| | - Chen Ling
- Laboratory of Genetics and Genomics, National Institute on Aging, NIH, 251 Bayview Blvd., Baltimore, MD 21224, USA
| | - Zhijiang Yan
- Institute of DNA Repair Diseases, School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Dongyi Xu
- Peking University, Beijing 100871, China
| | - Junjie Chen
- Department Experimental Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77225-0334, USA
| | - Amom Ruhikanta Meetei
- Division of Experimental Hematology and Cancer Biology and Cancer & Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Lei Li
- Department Experimental Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77225-0334, USA
| | - Weidong Wang
- Laboratory of Genetics and Genomics, National Institute on Aging, NIH, 251 Bayview Blvd., Baltimore, MD 21224, USA
| | - Michael M Seidman
- Laboratory of Molecular Gerontology, National Institute on Aging, NIH, 251 Bayview Blvd., Baltimore, MD 21224, USA.
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47
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Son MY, Hasty P. Homologous recombination defects and how they affect replication fork maintenance. AIMS GENETICS 2019; 5:192-211. [PMID: 31435521 PMCID: PMC6690234 DOI: 10.3934/genet.2018.4.192] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 03/18/2019] [Indexed: 01/07/2023]
Abstract
Homologous recombination (HR) repairs DNA double strand breaks (DSBs) and stabilizes replication forks (RFs). RAD51 is the recombinase for the HR pathway. To preserve genomic integrity, RAD51 forms a filament on the 3' end of a DSB and on a single-stranded DNA (ssDNA) gap. But unregulated HR results in undesirable chromosomal rearrangements. This review describes the multiple mechanisms that regulate HR with a focus on those mechanisms that promote and contain RAD51 filaments to limit chromosomal rearrangements. If any of these pathways break down and HR becomes unregulated then disease, primarily cancer, can result.
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Affiliation(s)
- Mi Young Son
- Department of Molecular Medicine and Institute of Biotechnology, UT Health San Antonio, 15355 Lambda Drive, San Antonio, USA
| | - Paul Hasty
- Department of Molecular Medicine and Institute of Biotechnology, UT Health San Antonio, 15355 Lambda Drive, San Antonio, USA
- The Mays Cancer Center, USA
- Sam and Ann Barshop Institute for Longevity and Aging Studies, USA
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48
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Basbous J, Constantinou A. A tumor suppressive DNA translocase named FANCM. Crit Rev Biochem Mol Biol 2019; 54:27-40. [DOI: 10.1080/10409238.2019.1568963] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Jihane Basbous
- Institute of Human Genetics (IGH), Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM), Montpellier, France
| | - Angelos Constantinou
- Institute of Human Genetics (IGH), Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM), Montpellier, France
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49
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Andreev V, Hristova R, Asparuhova M, Danovski G, Stoynov S, Gospodinov A. Mammalian INO80 chromatin remodeler cooperates with FANCM to mediate DNA interstrand crosslink-induced checkpoint activation and repair. DNA Repair (Amst) 2019; 74:38-50. [DOI: 10.1016/j.dnarep.2018.12.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 11/30/2018] [Accepted: 12/27/2018] [Indexed: 11/30/2022]
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50
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Wang H, Li S, Zhang H, Wang Y, Hao S, Wu X. BLM prevents instability of structure-forming DNA sequences at common fragile sites. PLoS Genet 2018; 14:e1007816. [PMID: 30496191 PMCID: PMC6289451 DOI: 10.1371/journal.pgen.1007816] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 12/11/2018] [Accepted: 11/07/2018] [Indexed: 01/04/2023] Open
Abstract
Genome instability often arises at common fragile sites (CFSs) leading to cancer-associated chromosomal rearrangements. However, the underlying mechanisms of how CFS protection is achieved is not well understood. We demonstrate that BLM plays an important role in the maintenance of genome stability of structure-forming AT-rich sequences derived from CFSs (CFS-AT). BLM deficiency leads to increased DSB formation and hyper mitotic recombination at CFS-AT and induces instability of the plasmids containing CFS-AT. We further showed that BLM is required for suppression of CFS breakage upon oncogene expression. Both helicase activity and ATR-mediated phosphorylation of BLM are important for preventing genetic instability at CFS-AT sequences. Furthermore, the role of BLM in protecting CFS-AT is not epistatic to that of FANCM, a translocase that is involved in preserving CFS stability. Loss of BLM helicase activity leads to drastic decrease of cell viability in FANCM deficient cells. We propose that BLM and FANCM utilize different mechanisms to remove DNA secondary structures forming at CFS-AT on replication forks, thereby preventing DSB formation and maintaining CFS stability. Common fragile sites (CFSs) are large chromosomal regions which are more prone to breakage than other places in the genome. They are a part of normal chromosome structure and are present in all human beings, but are also hotspots for chromosomal rearrangement during oncogenesis. Understanding how CFSs are protected to prevent genome instability is thus extremely important for revealing the mechanism underlying cancer development. We found that Bloom syndrome protein BLM is involved in resolving DNA secondary structures that arise at AT-rich sequences in CFSs, suggesting a critical function of BLM in protecting CFSs. We also found that this BLM function is distinct from the role of Fanconi anemia protein FANCM in protecting CFSs, and loss of both BLM and FANCM activities leads to cell death. These studies reveal important mechanisms of the maintenance of CFS stability in mammalian cells.
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Affiliation(s)
- Hailong Wang
- Beijing Key Laboratory of DNA Damage Response and College of Life Science, Capital Normal University, Beijing, China
| | - Shibo Li
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
| | - Huimin Zhang
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
| | - Ya Wang
- Beijing Key Laboratory of DNA Damage Response and College of Life Science, Capital Normal University, Beijing, China
| | - Shuailin Hao
- Beijing Key Laboratory of DNA Damage Response and College of Life Science, Capital Normal University, Beijing, China
| | - Xiaohua Wu
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
- * E-mail:
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