1
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Scelfo A, Angrisani A, Grillo M, Barnes BM, Muyas F, Sauer CM, Leung CWB, Dumont M, Grison M, Mazaud D, Garnier M, Guintini L, Nelson L, Esashi F, Cortés-Ciriano I, Taylor SS, Déjardin J, Wilhelm T, Fachinetti D. Specialized replication mechanisms maintain genome stability at human centromeres. Mol Cell 2024; 84:1003-1020.e10. [PMID: 38359824 DOI: 10.1016/j.molcel.2024.01.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 12/12/2023] [Accepted: 01/19/2024] [Indexed: 02/17/2024]
Abstract
The high incidence of whole-arm chromosome aneuploidy and translocations in tumors suggests instability of centromeres, unique loci built on repetitive sequences and essential for chromosome separation. The causes behind this fragility and the mechanisms preserving centromere integrity remain elusive. We show that replication stress, hallmark of pre-cancerous lesions, promotes centromeric breakage in mitosis, due to spindle forces and endonuclease activities. Mechanistically, we unveil unique dynamics of the centromeric replisome distinct from the rest of the genome. Locus-specific proteomics identifies specialized DNA replication and repair proteins at centromeres, highlighting them as difficult-to-replicate regions. The translesion synthesis pathway, along with other factors, acts to sustain centromere replication and integrity. Prolonged stress causes centromeric alterations like ruptures and translocations, as observed in ovarian cancer models experiencing replication stress. This study provides unprecedented insights into centromere replication and integrity, proposing mechanistic insights into the origins of centromere alterations leading to abnormal cancerous karyotypes.
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Affiliation(s)
- Andrea Scelfo
- Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR144, 26 rue d'Ulm, Paris 75005, France
| | - Annapaola Angrisani
- Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR144, 26 rue d'Ulm, Paris 75005, France
| | - Marco Grillo
- Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR144, 26 rue d'Ulm, Paris 75005, France
| | - Bethany M Barnes
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Cancer Research Centre, Wilmslow Road, Manchester M20 4GJ, UK
| | - Francesc Muyas
- European Molecular Biology Laboratory, European Bioinformatics Institute, Hinxton, Cambridge CB10 1SD, UK
| | - Carolin M Sauer
- European Molecular Biology Laboratory, European Bioinformatics Institute, Hinxton, Cambridge CB10 1SD, UK
| | | | - Marie Dumont
- Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR144, 26 rue d'Ulm, Paris 75005, France
| | - Marine Grison
- Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR144, 26 rue d'Ulm, Paris 75005, France
| | - David Mazaud
- Plateforme Imagerie PICT-IBiSA, Institut Curie, PSL Research University, Paris 75005, France; Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR3664, 26 rue d'Ulm, Paris 75005, France
| | - Mickaël Garnier
- Plateforme Imagerie PICT-IBiSA, Institut Curie, PSL Research University, Paris 75005, France; Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR3664, 26 rue d'Ulm, Paris 75005, France
| | - Laetitia Guintini
- Institute of Human Genetics, CNRS-Université de Montpellier, Montpellier 34396, France
| | - Louisa Nelson
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Cancer Research Centre, Wilmslow Road, Manchester M20 4GJ, UK
| | - Fumiko Esashi
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Isidro Cortés-Ciriano
- European Molecular Biology Laboratory, European Bioinformatics Institute, Hinxton, Cambridge CB10 1SD, UK
| | - Stephen S Taylor
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Cancer Research Centre, Wilmslow Road, Manchester M20 4GJ, UK
| | - Jérôme Déjardin
- Institute of Human Genetics, CNRS-Université de Montpellier, Montpellier 34396, France
| | - Therese Wilhelm
- Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR144, 26 rue d'Ulm, Paris 75005, France; Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR3664, 26 rue d'Ulm, Paris 75005, France.
| | - Daniele Fachinetti
- Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR144, 26 rue d'Ulm, Paris 75005, France; Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR3664, 26 rue d'Ulm, Paris 75005, France.
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2
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Shi R, Wang S, Jiang Y, Zhong G, Li M, Sun Y. ERCC4: a potential regulatory factor in inflammatory bowel disease and inflammation-associated colorectal cancer. Front Endocrinol (Lausanne) 2024; 15:1348216. [PMID: 38516408 PMCID: PMC10954797 DOI: 10.3389/fendo.2024.1348216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 02/19/2024] [Indexed: 03/23/2024] Open
Abstract
The pathogenesis of inflammatory bowel disease (IBD) remains unclear and is associated with an increased risk of developing colitis-associated cancer (CAC). Under sustained inflammatory stimulation in the intestines, loss of early DNA damage response genes can lead to tumor formation. Many proteins are involved in the pathways of DNA damage response and play critical roles in protecting genes from various potential damages that DNA may undergo. ERCC4 is a structure-specific endonuclease that participates in the nucleotide excision repair (NER) pathway. The catalytic site of ERCC4 determines the activity of NER and is an indispensable gene in the NER pathway. ERCC4 may be involved in the imbalanced process of DNA damage and repair in IBD-related inflammation and CAC. This article primarily reviews the function of ERCC4 in the DNA repair pathway and discusses its potential role in the processes of IBD-related inflammation and carcinogenesis. Finally, we explore how this knowledge may open novel avenues for the treatment of IBD and IBD-related cancer.
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Affiliation(s)
| | | | | | | | | | - Yan Sun
- *Correspondence: Yan Sun, ; Mingsong Li,
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3
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Li Y, Zhang Y, Shah SB, Chang CY, Wang H, Wu X. MutSβ protects common fragile sites by facilitating homology-directed repair at DNA double-strand breaks with secondary structures. Nucleic Acids Res 2024; 52:1120-1135. [PMID: 38038265 PMCID: PMC10853791 DOI: 10.1093/nar/gkad1112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/14/2023] [Accepted: 11/07/2023] [Indexed: 12/02/2023] Open
Abstract
Common fragile sites (CFSs) are regions prone to chromosomal rearrangements, thereby contributing to tumorigenesis. Under replication stress (RS), CFSs often harbor under-replicated DNA regions at the onset of mitosis, triggering homology-directed repair known as mitotic DNA synthesis (MiDAS) to complete DNA replication. In this study, we identified an important role of DNA mismatch repair protein MutSβ (MSH2/MSH3) in facilitating MiDAS and maintaining CFS stability. Specifically, we demonstrated that MutSβ is required for the increased mitotic recombination induced by RS or FANCM loss at CFS-derived AT-rich and structure-prone sequences (CFS-ATs). We also found that MSH3 exhibits synthetic lethality with FANCM. Mechanistically, MutSβ is required for homologous recombination (HR) especially when DNA double-strand break (DSB) ends contain secondary structures. We also showed that upon RS, MutSβ is recruited to Flex1, a specific CFS-AT, in a PCNA-dependent but MUS81-independent manner. Furthermore, MutSβ interacts with RAD52 and promotes RAD52 recruitment to Flex1 following MUS81-dependent fork cleavage. RAD52, in turn, recruits XPF/ERCC1 to remove DNA secondary structures at DSB ends, enabling HR/break-induced replication (BIR) at CFS-ATs. We propose that the specific requirement of MutSβ in processing DNA secondary structures at CFS-ATs underlies its crucial role in promoting MiDAS and maintaining CFS integrity.
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Affiliation(s)
- Youhang Li
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing 100048, China
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Yunkun Zhang
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Sameer Bikram Shah
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Chia-Yu Chang
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Hailong Wang
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Xiaohua Wu
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
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4
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Medina-Rivera M, Phelps S, Sridharan M, Becker J, Lamb N, Kumar C, Sutton M, Bielinsky A, Balakrishnan L, Surtees J. Elevated MSH2 MSH3 expression interferes with DNA metabolism in vivo. Nucleic Acids Res 2023; 51:12185-12206. [PMID: 37930834 PMCID: PMC10711559 DOI: 10.1093/nar/gkad934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 09/30/2023] [Accepted: 10/10/2023] [Indexed: 11/08/2023] Open
Abstract
The Msh2-Msh3 mismatch repair (MMR) complex in Saccharomyces cerevisiae recognizes and directs repair of insertion/deletion loops (IDLs) up to ∼17 nucleotides. Msh2-Msh3 also recognizes and binds distinct looped and branched DNA structures with varying affinities, thereby contributing to genome stability outside post-replicative MMR through homologous recombination, double-strand break repair (DSBR) and the DNA damage response. In contrast, Msh2-Msh3 promotes genome instability through trinucleotide repeat (TNR) expansions, presumably by binding structures that form from single-stranded (ss) TNR sequences. We previously demonstrated that Msh2-Msh3 binding to 5' ssDNA flap structures interfered with Rad27 (Fen1 in humans)-mediated Okazaki fragment maturation (OFM) in vitro. Here we demonstrate that elevated Msh2-Msh3 levels interfere with DNA replication and base excision repair in vivo. Elevated Msh2-Msh3 also induced a cell cycle arrest that was dependent on RAD9 and ELG1 and led to PCNA modification. These phenotypes also required Msh2-Msh3 ATPase activity and downstream MMR proteins, indicating an active mechanism that is not simply a result of Msh2-Msh3 DNA-binding activity. This study provides new mechanistic details regarding how excess Msh2-Msh3 can disrupt DNA replication and repair and highlights the role of Msh2-Msh3 protein abundance in Msh2-Msh3-mediated genomic instability.
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Affiliation(s)
- Melisa Medina-Rivera
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo NY, 14203, USA
| | - Samantha Phelps
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo NY, 14203, USA
| | - Madhumita Sridharan
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, 46202, USA
| | - Jordan Becker
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Natalie A Lamb
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo NY, 14203, USA
| | - Charanya Kumar
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo NY, 14203, USA
| | - Mark D Sutton
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo NY, 14203, USA
| | - Anja Bielinsky
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Lata Balakrishnan
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, 46202, USA
| | - Jennifer A Surtees
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo NY, 14203, USA
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5
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Bai G, Endres T, Kühbacher U, Greer BH, Peacock EM, Crossley MP, Sathirachinda A, Cortez D, Eichman BF, Cimprich KA. HLTF Prevents G4 Accumulation and Promotes G4-induced Fork Slowing to Maintain Genome Stability. bioRxiv 2023:2023.10.27.563641. [PMID: 37961428 PMCID: PMC10634870 DOI: 10.1101/2023.10.27.563641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
G-quadruplexes (G4s) form throughout the genome and influence important cellular processes, but their deregulation can challenge DNA replication fork progression and threaten genome stability. Here, we demonstrate an unexpected, dual role for the dsDNA translocase HLTF in G4 metabolism. First, we find that HLTF is enriched at G4s in the human genome and suppresses G4 accumulation throughout the cell cycle using its ATPase activity. This function of HLTF affects telomere maintenance by restricting alternative lengthening of telomeres, a process stimulated by G4s. We also show that HLTF and MSH2, a mismatch repair factor that binds G4s, act in independent pathways to suppress G4s and to promote resistance to G4 stabilization. In a second, distinct role, HLTF restrains DNA synthesis upon G4 stabilization by suppressing PrimPol-dependent repriming. Together, the dual functions of HLTF in the G4 response prevent DNA damage and potentially mutagenic replication to safeguard genome stability.
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6
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Wang L, Xue Y, Yang S, Bo T, Xu J, Wang W. Mismatch Repair Protein Msh2 Is Necessary for Macronuclear Stability and Micronuclear Division in Tetrahymena thermophila. Int J Mol Sci 2023; 24:10559. [PMID: 37445734 DOI: 10.3390/ijms241310559] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 06/20/2023] [Accepted: 06/22/2023] [Indexed: 07/15/2023] Open
Abstract
Mismatch repair (MMR) is a conserved mechanism that is primarily responsible for the repair of DNA mismatches during DNA replication. Msh2 forms MutS heterodimer complexes that initiate the MMR in eukaryotes. The function of Msh2 is less clear under different chromatin structures. Tetrahymena thermophila contains a transcriptionally active macronucleus (MAC) and a transcriptionally silent micronucleus (MIC) in the same cytoplasm. Msh2 is localized in the MAC and MIC during vegetative growth. Msh2 is localized in the perinuclear region around the MIC and forms a spindle-like structure as the MIC divides. During the early conjugation stage, Msh2 is localized in the MIC and disappears from the parental MAC. Msh2 is localized in the new MAC and new MIC during the late conjugation stage. Msh2 also forms a spindle-like structure with a meiotic MIC and mitotic gametic nucleus. MSH2 knockdown inhibits the division of MAC and MIC during vegetative growth and affects cellular proliferation. MSH2 knockdown mutants are sensitive to cisplatin treatment. MSH2 knockdown also affects micronuclear meiosis and gametogenesis during sexual development. Furthermore, Msh2 interacts with MMR-dependent and MMR-independent factors. Therefore, Msh2 is necessary for macronuclear stability, as well as micronuclear mitosis and meiosis in Tetrahymena.
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Affiliation(s)
- Lin Wang
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan 030006, China
| | - Yuhuan Xue
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan 030006, China
| | - Sitong Yang
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan 030006, China
| | - Tao Bo
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan 030006, China
- Shanxi Key Laboratory of Biotechnology, Taiyuan 030006, China
| | - Jing Xu
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan 030006, China
- School of Life Science, Shanxi University, Taiyuan 030006, China
| | - Wei Wang
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan 030006, China
- Shanxi Key Laboratory of Biotechnology, Taiyuan 030006, China
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7
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Alghoul E, Paloni M, Takedachi A, Urbach S, Barducci A, Gaillard PH, Basbous J, Constantinou A. Compartmentalization of the SUMO/RNF4 pathway by SLX4 drives DNA repair. Mol Cell 2023; 83:1640-1658.e9. [PMID: 37059091 DOI: 10.1016/j.molcel.2023.03.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 02/06/2023] [Accepted: 03/21/2023] [Indexed: 04/16/2023]
Abstract
SLX4, disabled in the Fanconi anemia group P, is a scaffolding protein that coordinates the action of structure-specific endonucleases and other proteins involved in the replication-coupled repair of DNA interstrand cross-links. Here, we show that SLX4 dimerization and SUMO-SIM interactions drive the assembly of SLX4 membraneless compartments in the nucleus called condensates. Super-resolution microscopy reveals that SLX4 forms chromatin-bound clusters of nanocondensates. We report that SLX4 compartmentalizes the SUMO-RNF4 signaling pathway. SENP6 and RNF4 regulate the assembly and disassembly of SLX4 condensates, respectively. SLX4 condensation per se triggers the selective modification of proteins by SUMO and ubiquitin. Specifically, SLX4 condensation induces ubiquitylation and chromatin extraction of topoisomerase 1 DNA-protein cross-links. SLX4 condensation also induces the nucleolytic degradation of newly replicated DNA. We propose that the compartmentalization of proteins by SLX4 through site-specific interactions ensures the spatiotemporal control of protein modifications and nucleolytic reactions during DNA repair.
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Affiliation(s)
- Emile Alghoul
- Institut de Génétique Humaine, Université de Montpellier, CNRS, Montpellier, France
| | - Matteo Paloni
- Centre de Biologie Structurale (CBS), Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Arato Takedachi
- Aix Marseille Univ, CNRS, INSERM, Institut Paoli-Calmettes, CRCM, Marseille, France
| | - Serge Urbach
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France; Montpellier RIO Imaging, Montpellier, France
| | - Alessandro Barducci
- Centre de Biologie Structurale (CBS), Université de Montpellier, CNRS, INSERM, Montpellier, France
| | | | - Jihane Basbous
- Institut de Génétique Humaine, Université de Montpellier, CNRS, Montpellier, France.
| | - Angelos Constantinou
- Institut de Génétique Humaine, Université de Montpellier, CNRS, Montpellier, France.
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8
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Benitez A, Sebald M, Kanagaraj R, Rodrigo-Brenni MC, Chan YW, Liang CC, West SC. GEN1 promotes common fragile site expression. Cell Rep 2023; 42:112062. [PMID: 36729836 DOI: 10.1016/j.celrep.2023.112062] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 11/01/2022] [Accepted: 01/18/2023] [Indexed: 02/03/2023] Open
Abstract
Our genomes harbor conserved DNA sequences, known as common fragile sites (CFSs), that are difficult to replicate and correspond to regions of genome instability. Following replication stress, CFS loci give rise to breaks or gaps (termed CFS expression) where under-replicated DNA subsequently undergoes mitotic DNA synthesis (MiDAS). We show that loss of the structure-selective endonuclease GEN1 reduces CFS expression, leading to defects in MiDAS, ultrafine anaphase bridge formation, and DNA damage in the ensuing cell cycle due to aberrant chromosome segregation. GEN1 knockout cells also exhibit an elevated frequency of bichromatid constrictions consistent with the presence of unresolved regions of under-replicated DNA. Previously, the role of GEN1 was thought to be restricted to the nucleolytic resolution of recombination intermediates. However, its ability to cleave under-replicated DNA at CFS loci indicates that GEN1 plays a dual role resolving both DNA replication and recombination intermediates before chromosome segregation.
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Affiliation(s)
- Anaid Benitez
- The Francis Crick Institute, DNA Recombination and Repair Laboratory, 1 Midland Road, London NW1 1AT, UK
| | - Marie Sebald
- The Francis Crick Institute, DNA Recombination and Repair Laboratory, 1 Midland Road, London NW1 1AT, UK
| | - Radhakrishnan Kanagaraj
- The Francis Crick Institute, DNA Recombination and Repair Laboratory, 1 Midland Road, London NW1 1AT, UK
| | - Monica C Rodrigo-Brenni
- The Francis Crick Institute, DNA Recombination and Repair Laboratory, 1 Midland Road, London NW1 1AT, UK
| | - Ying Wai Chan
- The Francis Crick Institute, DNA Recombination and Repair Laboratory, 1 Midland Road, London NW1 1AT, UK
| | - Chih-Chao Liang
- The Francis Crick Institute, DNA Recombination and Repair Laboratory, 1 Midland Road, London NW1 1AT, UK
| | - Stephen C West
- The Francis Crick Institute, DNA Recombination and Repair Laboratory, 1 Midland Road, London NW1 1AT, UK.
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9
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Mengoli V, Ceppi I, Sanchez A, Cannavo E, Halder S, Scaglione S, Gaillard P, McHugh PJ, Riesen N, Pettazzoni P, Cejka P. WRN helicase and mismatch repair complexes independently and synergistically disrupt cruciform DNA structures. EMBO J 2023; 42:e111998. [PMID: 36541070 PMCID: PMC9890227 DOI: 10.15252/embj.2022111998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 11/07/2022] [Accepted: 12/06/2022] [Indexed: 12/24/2022] Open
Abstract
The Werner Syndrome helicase, WRN, is a promising therapeutic target in cancers with microsatellite instability (MSI). Long-term MSI leads to the expansion of TA nucleotide repeats proposed to form cruciform DNA structures, which in turn cause DNA breaks and cell lethality upon WRN downregulation. Here we employed biochemical assays to show that WRN helicase can efficiently and directly unfold cruciform structures, thereby preventing their cleavage by the SLX1-SLX4 structure-specific endonuclease. TA repeats are particularly prone to form cruciform structures, explaining why these DNA sequences are preferentially broken in MSI cells upon WRN downregulation. We further demonstrate that the activity of the DNA mismatch repair (MMR) complexes MutSα (MSH2-MSH6), MutSβ (MSH2-MSH3), and MutLα (MLH1-PMS2) similarly decreases the level of DNA cruciforms, although the mechanism is different from that employed by WRN. When combined, WRN and MutLα exhibited higher than additive effects in in vitro cruciform processing, suggesting that WRN and the MMR proteins may cooperate. Our data explain how WRN and MMR defects cause genome instability in MSI cells with expanded TA repeats, and provide a mechanistic basis for their recently discovered synthetic-lethal interaction with promising applications in precision cancer therapy.
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Affiliation(s)
- Valentina Mengoli
- Faculty of Biomedical Sciences, Institute for Research in BiomedicineUniversità della Svizzera italiana (USI)BellinzonaSwitzerland
| | - Ilaria Ceppi
- Faculty of Biomedical Sciences, Institute for Research in BiomedicineUniversità della Svizzera italiana (USI)BellinzonaSwitzerland
| | - Aurore Sanchez
- Faculty of Biomedical Sciences, Institute for Research in BiomedicineUniversità della Svizzera italiana (USI)BellinzonaSwitzerland
| | - Elda Cannavo
- Faculty of Biomedical Sciences, Institute for Research in BiomedicineUniversità della Svizzera italiana (USI)BellinzonaSwitzerland
| | - Swagata Halder
- Faculty of Biomedical Sciences, Institute for Research in BiomedicineUniversità della Svizzera italiana (USI)BellinzonaSwitzerland
| | - Sarah Scaglione
- Centre de Recherche en Cancérologie de Marseille, CRCM, Inserm, CNRS, Aix‐Marseille Université, Institut Paoli‐CalmettesMarseilleFrance
| | - Pierre‐Henri Gaillard
- Centre de Recherche en Cancérologie de Marseille, CRCM, Inserm, CNRS, Aix‐Marseille Université, Institut Paoli‐CalmettesMarseilleFrance
| | - Peter J McHugh
- Department of Oncology, MRC Weatherall Institute of Molecular Medicine, John Radcliffe HospitalUniversity of OxfordOxfordUK
| | - Nathalie Riesen
- Roche Pharma Research & Early Development pREDRoche Innovation CenterBaselSwitzerland
| | | | - Petr Cejka
- Faculty of Biomedical Sciences, Institute for Research in BiomedicineUniversità della Svizzera italiana (USI)BellinzonaSwitzerland
- Department of Biology, Institute of BiochemistryEidgenössische Technische Hochschule (ETH)ZürichSwitzerland
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10
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Song Q, Hu Y, Yin A, Wang H, Yin Q. DNA Holliday Junction: History, Regulation and Bioactivity. Int J Mol Sci 2022; 23:ijms23179730. [PMID: 36077130 PMCID: PMC9456528 DOI: 10.3390/ijms23179730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 08/16/2022] [Accepted: 08/18/2022] [Indexed: 11/16/2022] Open
Abstract
DNA Holliday junction (HJ) is a four-way stranded DNA intermediate that formed in replication fork regression, homology-dependent repair and mitosis, performing a significant role in genomic stability. Failure to remove HJ can induce an acceptable replication fork stalling and DNA damage in normal cells, leading to a serious chromosomal aberration and even cell death in HJ nuclease-deficient tumor cells. Thus, HJ is becoming an attractive target in cancer therapy. However, the development of HJ-targeting ligand faces great challenges because of flexile cavities on the center of HJs. This review introduces the discovery history of HJ, elucidates the formation and dissociation procedures of HJ in corresponding bio-events, emphasizes the importance of prompt HJ-removing in genome stability, and summarizes recent advances in HJ-based ligand discovery. Our review indicate that target HJ is a promising approach in oncotherapy.
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Affiliation(s)
- Qinqin Song
- State/Key Laboratory of Microbial Technology, Shandong University, 72 Jimo Binhai Road, Qingdao 266237, China
| | - Yuemiao Hu
- Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, School of Pharmacy, Yantai University, 30 Qingquan Road, Yantai 264005, China
| | - Anqi Yin
- Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, School of Pharmacy, Yantai University, 30 Qingquan Road, Yantai 264005, China
| | - Hongbo Wang
- Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, School of Pharmacy, Yantai University, 30 Qingquan Road, Yantai 264005, China
| | - Qikun Yin
- Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, School of Pharmacy, Yantai University, 30 Qingquan Road, Yantai 264005, China
- Bohai Rim Advanced Research Institute for Drug Discovery, 198 Binhai East Road, Yantai 264005, China
- Correspondence:
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11
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Elango R, Panday A, Lach FP, Willis NA, Nicholson K, Duffey EE, Smogorzewska A, Scully R. The structure-specific endonuclease complex SLX4-XPF regulates Tus-Ter-induced homologous recombination. Nat Struct Mol Biol 2022; 29:801-812. [PMID: 35941380 PMCID: PMC9941964 DOI: 10.1038/s41594-022-00812-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 07/05/2022] [Indexed: 02/08/2023]
Abstract
Vertebrate replication forks arrested at interstrand DNA cross-links (ICLs) engage the Fanconi anemia pathway to incise arrested forks, 'unhooking' the ICL and forming a double strand break (DSB) that is repaired by homologous recombination (HR). The FANCP product, SLX4, in complex with the XPF (also known as FANCQ or ERCC4)-ERCC1 endonuclease, mediates ICL unhooking. Whether this mechanism operates at replication fork barriers other than ICLs is unknown. Here, we study the role of mouse SLX4 in HR triggered by a site-specific chromosomal DNA-protein replication fork barrier formed by the Escherichia coli-derived Tus-Ter complex. We show that SLX4-XPF is required for Tus-Ter-induced HR but not for error-free HR induced by a replication-independent DSB. We additionally uncover a role for SLX4-XPF in DSB-induced long-tract gene conversion, an error-prone HR pathway related to break-induced replication. Notably, Slx4 and Xpf mutants that are defective for Tus-Ter-induced HR are hypersensitive to ICLs and also to the DNA-protein cross-linking agents 5-aza-2'-deoxycytidine and zebularine. Collectively, these findings show that SLX4-XPF can process DNA-protein fork barriers for HR and that the Tus-Ter system recapitulates this process.
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Affiliation(s)
- Rajula Elango
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Arvind Panday
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Francis P Lach
- Laboratory of Genome Maintenance, The Rockefeller University, New York, NY, 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, USA
| | - Kaitlin Nicholson
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, 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, USA
| | - Agata Smogorzewska
- Laboratory of Genome Maintenance, The Rockefeller University, New York, NY, 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, USA.
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12
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Ho HN, West SC. Generation of double Holliday junction DNAs and their dissolution/resolution within a chromatin context. Proc Natl Acad Sci U S A 2022; 119:e2123420119. [PMID: 35452329 PMCID: PMC9170140 DOI: 10.1073/pnas.2123420119] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 03/20/2022] [Indexed: 12/31/2022] Open
Abstract
Four-way DNA intermediates, also known as Holliday junctions (HJs), are formed during homologous recombination and DNA repair, and their resolution is necessary for proper chromosome segregation. To facilitate the biochemical analysis of HJ processing, we developed a method involving DNAzyme self-cleavage to generate 1.8-kb DNA molecules containing either single (sHJ) or double Holliday junctions (dHJs). We show that dHJ DNAs (referred to as HoJo DNAs) are dissolved by the human BLM–TopIIIα–RMI1–RMI2 complex to form two noncrossover products. However, structure-selective endonucleases (human GEN1 and SMX complex) resolve DNA containing single or double HJs to yield a mixture of crossover and noncrossover products. Finally, we demonstrate that chromatin inhibits the resolution of the double HJ by GEN or SMX while allowing BTRR-mediated dissolution.
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Affiliation(s)
- Han N. Ho
- DNA Recombination and Repair Laboratory, Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Stephen C. West
- DNA Recombination and Repair Laboratory, Francis Crick Institute, London NW1 1AT, United Kingdom
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13
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Guervilly JH, Blin M, Laureti L, Baudelet E, Audebert S, Gaillard PH. SLX4 dampens MutSα-dependent mismatch repair. Nucleic Acids Res 2022; 50:2667-2680. [PMID: 35166826 PMCID: PMC8934664 DOI: 10.1093/nar/gkac075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 01/20/2022] [Accepted: 01/25/2022] [Indexed: 12/12/2022] Open
Abstract
The tumour suppressor SLX4 plays multiple roles in the maintenance of genome stability, acting as a scaffold for structure-specific endonucleases and other DNA repair proteins. It directly interacts with the mismatch repair (MMR) protein MSH2 but the significance of this interaction remained unknown until recent findings showing that MutSβ (MSH2-MSH3) stimulates in vitro the SLX4-dependent Holliday junction resolvase activity. Here, we characterize the mode of interaction between SLX4 and MSH2, which relies on an MSH2-interacting peptide (SHIP box) that drives interaction of SLX4 with both MutSβ and MutSα (MSH2-MSH6). While we show that this MSH2 binding domain is dispensable for the well-established role of SLX4 in interstrand crosslink repair, we find that it mediates inhibition of MutSα-dependent MMR by SLX4, unravelling an unanticipated function of SLX4.
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Affiliation(s)
- Jean-Hugues Guervilly
- Centre de Recherche en Cancérologie de Marseille, CRCM, Inserm, CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Marseille, France
| | - Marion Blin
- Centre de Recherche en Cancérologie de Marseille, CRCM, Inserm, CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Marseille, France
| | - Luisa Laureti
- Centre de Recherche en Cancérologie de Marseille, CRCM, Inserm, CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Marseille, France
| | - Emilie Baudelet
- Centre de Recherche en Cancérologie de Marseille, CRCM, Inserm, CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Marseille, France
| | - Stéphane Audebert
- Centre de Recherche en Cancérologie de Marseille, CRCM, Inserm, CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Marseille, France
| | - Pierre-Henri Gaillard
- Centre de Recherche en Cancérologie de Marseille, CRCM, Inserm, CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Marseille, France
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14
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Barroso-González J, García-Expósito L, Galaviz P, Lynskey ML, Allen JAM, Hoang S, Watkins SC, Pickett HA, O'Sullivan RJ. Anti-recombination function of MutSα restricts telomere extension by ALT-associated homology-directed repair. Cell Rep 2021; 37:110088. [PMID: 34879271 PMCID: PMC8724847 DOI: 10.1016/j.celrep.2021.110088] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 09/13/2021] [Accepted: 11/10/2021] [Indexed: 01/02/2023] Open
Abstract
Alternative lengthening of telomeres (ALT) is a telomere-elongation mechanism observed in ~15% of cancer subtypes. Current models indicate that ALT is mediated by homology-directed repair mechanisms. By disrupting MSH6 gene expression, we show that the deficiency of MutSα (MSH2/MSH6) DNA mismatch repair complex causes striking telomere hyperextension. Mechanistically, we show MutSα is specifically recruited to telomeres in ALT cells by associating with the proliferating-cell nuclear antigen (PCNA) subunit of the ALT telomere replisome. We also provide evidence that MutSα counteracts Bloom (BLM) helicase, which adopts a crucial role in stabilizing hyper-extended telomeres and maintaining the survival of MutSα-deficient ALT cancer cells. Lastly, we propose a model in which MutSα deficiency impairs heteroduplex rejection, leading to premature initiation of telomere DNA synthesis that coincides with an accumulation of telomere variant repeats (TVRs). These findings provide evidence that the MutSα DNA mismatch repair complex acts to restrain unwarranted ALT. Barroso-Gonzalez et al. show that the mismatch repair complex MutSα restricts the alternative lengthening of telomeres (ALT) pathway in cancer cells. MutSα has an anti-recombination function and limits recombination between heteroduplex sequences at telomeres, in part by counteracting the Bloom helicase (BLM).
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Affiliation(s)
- Jonathan Barroso-González
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Laura García-Expósito
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Pablo Galaviz
- Bioinformatics Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Michelle Lee Lynskey
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Joshua A M Allen
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - SongMy Hoang
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Simon C Watkins
- Department of Cell Biology, School of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Hilda A Pickett
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Roderick J O'Sullivan
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.
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15
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Payliss BJ, Patel A, Sheppard AC, Wyatt HDM. Exploring the Structures and Functions of Macromolecular SLX4-Nuclease Complexes in Genome Stability. Front Genet 2021; 12:784167. [PMID: 34804132 PMCID: PMC8599992 DOI: 10.3389/fgene.2021.784167] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 10/21/2021] [Indexed: 12/15/2022] Open
Abstract
All organisms depend on the ability of cells to accurately duplicate and segregate DNA into progeny. However, DNA is frequently damaged by factors in the environment and from within cells. One of the most dangerous lesions is a DNA double-strand break. Unrepaired breaks are a major driving force for genome instability. Cells contain sophisticated DNA repair networks to counteract the harmful effects of genotoxic agents, thus safeguarding genome integrity. Homologous recombination is a high-fidelity, template-dependent DNA repair pathway essential for the accurate repair of DNA nicks, gaps and double-strand breaks. Accurate homologous recombination depends on the ability of cells to remove branched DNA structures that form during repair, which is achieved through the opposing actions of helicases and structure-selective endonucleases. This review focuses on a structure-selective endonuclease called SLX1-SLX4 and the macromolecular endonuclease complexes that assemble on the SLX4 scaffold. First, we discuss recent developments that illuminate the structure and biochemical properties of this somewhat atypical structure-selective endonuclease. We then summarize the multifaceted roles that are fulfilled by human SLX1-SLX4 and its associated endonucleases in homologous recombination and genome stability. Finally, we discuss recent work on SLX4-binding proteins that may represent integral components of these macromolecular nuclease complexes, emphasizing the structure and function of a protein called SLX4IP.
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Affiliation(s)
- Brandon J Payliss
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Ayushi Patel
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Anneka C Sheppard
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Haley D M Wyatt
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada.,Canada Research Chairs Program, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
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16
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Sanchez A, Reginato G, Cejka P. Crossover or non-crossover outcomes: tailored processing of homologous recombination intermediates. Curr Opin Genet Dev 2021; 71:39-47. [PMID: 34293660 DOI: 10.1016/j.gde.2021.06.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/15/2021] [Accepted: 06/23/2021] [Indexed: 12/14/2022]
Abstract
DNA breaks may arise accidentally in vegetative cells or in a programmed manner in meiosis. The usage of a DNA template makes homologous recombination potentially error-free, however, recombination is not always accurate. Cells possess a remarkable capacity to tailor processing of recombination intermediates to fulfill a particular need. Vegetatively growing cells aim to maintain genome stability and therefore repair accidental breaks largely accurately, using sister chromatids as templates, into mostly non-crossovers products. Recombination in meiotic cells is instead more likely to employ homologous chromosomes as templates and result in crossovers to allow proper chromosome segregation and promote genetic diversity. Here we review models explaining the processing of recombination intermediates in vegetative and meiotic cells and its regulation, with a focus on MLH1-MLH3-dependent crossing-over during meiotic recombination.
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Affiliation(s)
- Aurore Sanchez
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, Switzerland
| | - Giordano Reginato
- 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
| | - 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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Young SJ, West SC. Coordinated roles of SLX4 and MutSβ in DNA repair and the maintenance of genome stability. Crit Rev Biochem Mol Biol 2021; 56:157-177. [PMID: 33596761 PMCID: PMC7610648 DOI: 10.1080/10409238.2021.1881433] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/06/2021] [Accepted: 01/22/2021] [Indexed: 12/14/2022]
Abstract
SLX4 provides a molecular scaffold for the assembly of multiple protein complexes required for the maintenance of genome stability. It is involved in the repair of DNA crosslinks, the resolution of recombination intermediates, the response to replication stress and the maintenance of telomere length. To carry out these diverse functions, SLX4 interacts with three structure-selective endonucleases, MUS81-EME1, SLX1 and XPF-ERCC1, as well as the telomere binding proteins TRF2, RTEL1 and SLX4IP. Recently, SLX4 was shown to interact with MutSβ, a heterodimeric protein involved in DNA mismatch repair, trinucleotide repeat instability, crosslink repair and recombination. Importantly, MutSβ promotes the pathogenic expansion of CAG/CTG trinucleotide repeats, which is causative of myotonic dystrophy and Huntington's disease. The colocalization and specific interaction of MutSβ with SLX4, together with their apparently overlapping functions, are suggestive of a common role in reactions that promote DNA maintenance and genome stability. This review will focus on the role of SLX4 in DNA repair, the interplay between MutSβ and SLX4, and detail how they cooperate to promote recombinational repair and DNA crosslink repair. Furthermore, we speculate that MutSβ and SLX4 may provide an alternative cellular mechanism that modulates trinucleotide instability.
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Affiliation(s)
- Sarah J Young
- DNA Recombination and Repair Laboratory, The Francis Crick Institute, London, UK
| | - Stephen C West
- DNA Recombination and Repair Laboratory, The Francis Crick Institute, London, UK
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