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McCoy MN, Adhikari M, Nitiss KC, Nitiss JL. Yeast Tools for Studying Type II Topoisomerases in Budding Yeast. Methods Mol Biol 2025; 2928:123-150. [PMID: 40372643 DOI: 10.1007/978-1-0716-4550-5_12] [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] [Indexed: 05/16/2025]
Abstract
DNA topoisomerases perform diverse functions in DNA metabolism. Type II topoisomerases, which carry out their reaction through a double-strand break intermediate, are absolutely required to separate replicated chromosomes prior to mitosis and play key roles in replication, transcription, and chromosome stability. The yeast Saccharomyces cerevisiae has been a premier system for exploring the biological roles of topoisomerases, and since type II enzymes are required for viability, the availability of conditional mutants greatly enhances the ability to dissect their biological roles. This chapter provides a critical discussion of yeast top2 mutants and plasmids for expressing and genetically manipulating the gene encoding the enzyme. An additional advantage of the yeast is the ability to functionally express human Top2α and Top2β in yeast to determine whether the human enzymes have unique characteristics that impact their biological functions. Therefore, this chapter also discusses plasmids that are available to express human Top2 enzymes in yeast. Finally, yeast has been particularly valuable in studying anti-cancer drugs that target Top2. This chapter discusses novel and powerful approaches for enhancing drug accumulation, allowing detailed examination of various topoisomerase inhibitors and poisons.
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Affiliation(s)
- Maureen Nie McCoy
- Pharmaceutical Sciences Department, Retzky College of Pharmacy, University of Illinois Chicago, Rockford, IL, USA
| | - Myna Adhikari
- Pharmaceutical Sciences Department, Retzky College of Pharmacy, University of Illinois Chicago, Rockford, IL, USA
- Biomedical Sciences Department, University of Illinois College of Medicine, Rockford, IL, USA
| | - Karin C Nitiss
- Pharmaceutical Sciences Department, Retzky College of Pharmacy, University of Illinois Chicago, Rockford, IL, USA
- Biomedical Sciences Department, University of Illinois College of Medicine, Rockford, IL, USA
| | - John L Nitiss
- Pharmaceutical Sciences Department, Retzky College of Pharmacy, University of Illinois Chicago, Rockford, IL, USA.
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2
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Keszthelyi A, Mansoubi S, Whale A, Houseley J, Baxter J. The fork protection complex generates DNA topological stress-induced DNA damage while ensuring full and faithful genome duplication. Proc Natl Acad Sci U S A 2024; 121:e2413631121. [PMID: 39589889 PMCID: PMC11626154 DOI: 10.1073/pnas.2413631121] [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: 07/08/2024] [Accepted: 10/14/2024] [Indexed: 11/28/2024] Open
Abstract
The fork protection complex (FPC), composed of Mrc1, Tof1, and Csm3, supports rapid and stable DNA replication. Here, we show that FPC activity also introduces DNA damage by increasing DNA topological stress during replication. Mrc1 action increases DNA topological stress during plasmid replication, while Mrc1 or Tof1 activity causes replication stress and DNA damage within topologically constrained regions. We show that the recruitment of Top1 to the fork by Tof1 suppresses the DNA damage generated in these loci. While FPC activity introduces some DNA damage due to increased topological stress, the FPC is also necessary to prevent DNA damage in long replicons across the genome, indicating that the FPC is required for complete and faithful genome duplication. We conclude that FPC regulation must balance ensuring full genome duplication through rapid replication with minimizing the consequential DNA topological stress-induced DNA damage caused by rapid replication through constrained regions.
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Affiliation(s)
- Andrea Keszthelyi
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, East SussexBN1 9RQ, United Kingdom
| | - Sahar Mansoubi
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, East SussexBN1 9RQ, United Kingdom
- Biology Department, North Tehran Branch, Islamic Azad University, Tehran1477893855, Iran
| | - Alex Whale
- Epigenetics Programme The Babraham Institute, Babraham Research Campus, CambridgeCB22 3AT, United Kingdom
| | - Jonathan Houseley
- Epigenetics Programme The Babraham Institute, Babraham Research Campus, CambridgeCB22 3AT, United Kingdom
| | - Jonathan Baxter
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, East SussexBN1 9RQ, United Kingdom
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3
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Jia X, Gao X, Zhang S, Inman JT, Hong Y, Singh A, Patel S, Wang MD. Torsion is a Dynamic Regulator of DNA Replication Stalling and Reactivation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.10.14.618227. [PMID: 39464009 PMCID: PMC11507786 DOI: 10.1101/2024.10.14.618227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/29/2024]
Abstract
The inherent helical structure of DNA dictates that a replisome must rotate relative to DNA during replication, presenting inevitable topological challenges to replication. However, little is known about how the replisome progresses against torsional stress. Here, we developed a label-free, high-resolution, real-time assay to monitor replisome movement under torsion. We visualized the replisome rotation of DNA and determined how the replisome slows down under torsion. We found that while helicase or DNA polymerase (DNAP) individually is a weak torsional motor, the replisome composed of both enzymes is the most powerful DNA torsional motor studied to date. It generates ~ 22 pN·nm of torque before stalling, twice the stall torque of E. coli RNA polymerase. Upon replisome stalling, the specific interaction between helicase and DNAP stabilizes the fork junction; without it, the fork can regress hundreds of base pairs. We also discovered that prolonged torsion-induced stalling inactivates the replisome. Surprisingly, DNAP exchange, mediated by the helicase, is highly effective in facilitating replication restart, but only if excess DNAP is present during stalling. Thus, helicase and DNA polymerase work synergistically as a powerful torsional motor, and their dynamic and fluid interactions are crucial for maintaining fork integrity under torsional stress. This work demonstrates that torsion is a strong regulator of DNA replication stalling and reactivation.
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Affiliation(s)
- Xiaomeng Jia
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA
- Department of Physics & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Xiang Gao
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA
- Department of Physics & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Shuming Zhang
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA
- Department of Physics & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - James T. Inman
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA
- Department of Physics & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Yifeng Hong
- Department of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14853, USA
| | - Anupam Singh
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA
| | - Smita Patel
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA
| | - Michelle D. Wang
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA
- Department of Physics & LASSP, Cornell University, Ithaca, NY 14853, USA
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4
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Hong Y, Park SH, Wang H, Wang MD. Geometry of Braided DNA Dictates Supercoiling Partition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.10.08.617221. [PMID: 39416030 PMCID: PMC11482784 DOI: 10.1101/2024.10.08.617221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2024]
Abstract
During DNA replication, the replisome must rotate relative to the DNA substrate, generating supercoiling that must be partitioned in front of or behind the replisome. Supercoiling partitioned behind the replisome may intertwine (or braid) daughter DNA molecules and restrict chromosome segregation. Supercoiling partitioning and torsional resistance at the replisome should depend on the geometry of the two daughter DNA molecules, determined by their end separations. However, experimental investigation of DNA braiding under well-defined DNA geometry has proven challenging. Here, we present methods to engineer braiding substrates of defined geometry, from minimal to significant end separations. We then directly measured the torque required to braid these substrates using an angular optical trap (AOT) and found that the torque required to initiate the braiding during the first 0.5 turn critically depends on the end separation. Once braiding started, we found that the subsequent effective twist persistence length of DNA braiding is about 20-30 nm, insensitive to the end separations. Our work highlights the crucial role of braiding geometry in dictating supercoiling partitioning and torque build-up during replication. It suggests that dynamic modulation of end separation on the daughter DNA molecules could serve as a mechanism to regulate replication progression in vivo.
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Affiliation(s)
- Yifeng Hong
- Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Seong ha Park
- Department of Physics & LASSP, Cornell University, Ithaca, NY 14853, USA
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA
| | - Hanjie Wang
- Department of Physics & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Michelle D. Wang
- Department of Physics & LASSP, Cornell University, Ithaca, NY 14853, USA
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA
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Jones RM, Reynolds-Winczura A, Gambus A. A Decade of Discovery-Eukaryotic Replisome Disassembly at Replication Termination. BIOLOGY 2024; 13:233. [PMID: 38666845 PMCID: PMC11048390 DOI: 10.3390/biology13040233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 03/23/2024] [Accepted: 03/25/2024] [Indexed: 04/28/2024]
Abstract
The eukaryotic replicative helicase (CMG complex) is assembled during DNA replication initiation in a highly regulated manner, which is described in depth by other manuscripts in this Issue. During DNA replication, the replicative helicase moves through the chromatin, unwinding DNA and facilitating nascent DNA synthesis by polymerases. Once the duplication of a replicon is complete, the CMG helicase and the remaining components of the replisome need to be removed from the chromatin. Research carried out over the last ten years has produced a breakthrough in our understanding, revealing that replication termination, and more specifically replisome disassembly, is indeed a highly regulated process. This review brings together our current understanding of these processes and highlights elements of the mechanism that are conserved or have undergone divergence throughout evolution. Finally, we discuss events beyond the classic termination of DNA replication in S-phase and go over the known mechanisms of replicative helicase removal from chromatin in these particular situations.
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Affiliation(s)
- Rebecca M. Jones
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK; (R.M.J.); (A.R.-W.)
- School of Biosciences, Aston University, Birmingham B4 7ET, UK
| | - Alicja Reynolds-Winczura
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK; (R.M.J.); (A.R.-W.)
| | - Agnieszka Gambus
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK; (R.M.J.); (A.R.-W.)
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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] [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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7
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Soliman TN, Keifenheim D, Parker PJ, Clarke DJ. Cell cycle responses to Topoisomerase II inhibition: Molecular mechanisms and clinical implications. J Cell Biol 2023; 222:e202209125. [PMID: 37955972 PMCID: PMC10641588 DOI: 10.1083/jcb.202209125] [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: 07/22/2023] [Revised: 10/24/2023] [Accepted: 10/25/2023] [Indexed: 11/15/2023] Open
Abstract
DNA Topoisomerase IIA (Topo IIA) is an enzyme that alters the topological state of DNA and is essential for the separation of replicated sister chromatids and the integrity of cell division. Topo IIA dysfunction activates cell cycle checkpoints, resulting in arrest in either the G2-phase or metaphase of mitosis, ultimately triggering the abscission checkpoint if non-disjunction persists. These events, which directly or indirectly monitor the activity of Topo IIA, have become of major interest as many cancers have deficiencies in Topoisomerase checkpoints, leading to genome instability. Recent studies into how cells sense Topo IIA dysfunction and respond by regulating cell cycle progression demonstrate that the Topo IIA G2 checkpoint is distinct from the G2-DNA damage checkpoint. Likewise, in mitosis, the metaphase Topo IIA checkpoint is separate from the spindle assembly checkpoint. Here, we integrate mechanistic knowledge of Topo IIA checkpoints with the current understanding of how cells regulate progression through the cell cycle to accomplish faithful genome transmission and discuss the opportunities this offers for therapy.
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Affiliation(s)
- Tanya N. Soliman
- Barts Cancer Institute, Queen Mary University London, London, UK
| | - Daniel Keifenheim
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN, USA
| | | | - Duncan J. Clarke
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN, USA
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8
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Lee J, Wu M, Inman JT, Singh G, Park SH, Lee JH, Fulbright RM, Hong Y, Jeong J, Berger JM, Wang MD. Chromatinization modulates topoisomerase II processivity. Nat Commun 2023; 14:6844. [PMID: 37891161 PMCID: PMC10611788 DOI: 10.1038/s41467-023-42600-z] [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: 02/12/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023] Open
Abstract
Type IIA topoisomerases are essential DNA processing enzymes that must robustly and reliably relax DNA torsional stress. While cellular processes constantly create varying torsional stress, how this variation impacts type IIA topoisomerase function remains obscure. Using multiple single-molecule approaches, we examined the torsional dependence of eukaryotic topoisomerase II (topo II) activity on naked DNA and chromatin. We observed that topo II is ~50-fold more processive on buckled DNA than previously estimated. We further discovered that topo II relaxes supercoiled DNA prior to plectoneme formation, but with processivity reduced by ~100-fold. This relaxation decreases with diminishing torsion, consistent with topo II capturing transient DNA loops. Topo II retains high processivity on buckled chromatin (~10,000 turns) and becomes highly processive even on chromatin under low torsional stress (~1000 turns), consistent with chromatin's predisposition to readily form DNA crossings. This work establishes that chromatin is a major stimulant of topo II function.
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Affiliation(s)
- Jaeyoon Lee
- Physics Department & LASSP, Cornell University, Ithaca, NY, 14853, USA
| | - Meiling Wu
- Physics Department & LASSP, Cornell University, Ithaca, NY, 14853, USA
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY, 14853, USA
| | - James T Inman
- Physics Department & LASSP, Cornell University, Ithaca, NY, 14853, USA
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY, 14853, USA
| | - Gundeep Singh
- Biophysics Program, Cornell University, Ithaca, NY, 14853, USA
| | - Seong Ha Park
- Biophysics Program, Cornell University, Ithaca, NY, 14853, USA
| | - Joyce H Lee
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | | | - Yifeng Hong
- Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Joshua Jeong
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - James M Berger
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Michelle D Wang
- Physics Department & LASSP, Cornell University, Ithaca, NY, 14853, USA.
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY, 14853, USA.
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Lee J, Wu M, Inman JT, Singh G, Park SH, Lee JH, Fulbright RM, Hong Y, Jeong J, Berger JM, Wang MD. Chromatinization Modulates Topoisomerase II Processivity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.03.560726. [PMID: 37873421 PMCID: PMC10592930 DOI: 10.1101/2023.10.03.560726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Type IIA topoisomerases are essential DNA processing enzymes that must robustly and reliably relax DNA torsional stress in vivo. While cellular processes constantly create different degrees of torsional stress, how this stress feeds back to control type IIA topoisomerase function remains obscure. Using a suite of single-molecule approaches, we examined the torsional impact on supercoiling relaxation of both naked DNA and chromatin by eukaryotic topoisomerase II (topo II). We observed that topo II was at least ~ 50-fold more processive on plectonemic DNA than previously estimated, capable of relaxing > 6000 turns. We further discovered that topo II could relax supercoiled DNA prior to plectoneme formation, but with a ~100-fold reduction in processivity; strikingly, the relaxation rate in this regime decreased with diminishing torsion in a manner consistent with the capture of transient DNA loops by topo II. Chromatinization preserved the high processivity of the enzyme under high torsional stress. Interestingly, topo II was still highly processive (~ 1000 turns) even under low torsional stress, consistent with the predisposition of chromatin to readily form DNA crossings. This work establishes that chromatin is a major stimulant of topo II function, capable of enhancing function even under low torsional stress.
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Affiliation(s)
- Jaeyoon Lee
- Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Meiling Wu
- Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA
| | - James T. Inman
- Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA
| | - Gundeep Singh
- Biophysics Program, Cornell University, Ithaca, NY 14853, USA
| | - Seong ha Park
- Biophysics Program, Cornell University, Ithaca, NY 14853, USA
| | - Joyce H. Lee
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | | | - Yifeng Hong
- Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Joshua Jeong
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - James M. Berger
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Michelle D. Wang
- Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA
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10
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Scelfo A, Fachinetti D. Centromere: A Trojan horse for genome stability. DNA Repair (Amst) 2023; 130:103569. [PMID: 37708591 DOI: 10.1016/j.dnarep.2023.103569] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 08/22/2023] [Accepted: 09/05/2023] [Indexed: 09/16/2023]
Abstract
Centromeres play a key role in the maintenance of genome stability to prevent carcinogenesis and diseases. They are specialized chromosome loci essential to ensure faithful transmission of genomic information across cell generations by mediating the interaction with spindle microtubules. Nonetheless, while fulfilling these essential roles, their distinct repetitive composition and susceptibility to mechanical stresses during cell division render them susceptible to breakage events. In this review, we delve into the present understanding of the underlying causes of centromere fragility, from the mechanisms governing its DNA replication and repair, to the pathways acting to counteract potential challenges. We propose that the centromere represents a "Trojan horse" exerting vital functions that, at the same time, potentially threatens whole genome stability.
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Affiliation(s)
- Andrea Scelfo
- Institut Curie, CNRS, UMR 144, Sorbonne University, 26 rue d'Ulm, 75005 Paris, France.
| | - Daniele Fachinetti
- Institut Curie, CNRS, UMR 144, Sorbonne University, 26 rue d'Ulm, 75005 Paris, France.
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11
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Jian JY, Osheroff N. Telling Your Right Hand from Your Left: The Effects of DNA Supercoil Handedness on the Actions of Type II Topoisomerases. Int J Mol Sci 2023; 24:11199. [PMID: 37446377 PMCID: PMC10342825 DOI: 10.3390/ijms241311199] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 07/05/2023] [Accepted: 07/05/2023] [Indexed: 07/15/2023] Open
Abstract
Type II topoisomerases are essential enzymes that modulate the topological state of DNA supercoiling in all living organisms. These enzymes alter DNA topology by performing double-stranded passage reactions on over- or underwound DNA substrates. This strand passage reaction generates a transient covalent enzyme-cleaved DNA structure known as the cleavage complex. Al-though the cleavage complex is a requisite catalytic intermediate, it is also intrinsically dangerous to genomic stability in biological systems. The potential threat of type II topoisomerase function can also vary based on the nature of the supercoiled DNA substrate. During essential processes such as DNA replication and transcription, cleavage complex formation can be inherently more dangerous on overwound versus underwound DNA substrates. As such, it is important to understand the profound effects that DNA topology can have on the cellular functions of type II topoisomerases. This review will provide a broad assessment of how human and bacterial type II topoisomerases recognize and act on their substrates of various topological states.
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Affiliation(s)
- Jeffrey Y. Jian
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA;
| | - Neil Osheroff
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA;
- Department of Medicine (Hematology/Oncology), Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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Campos LV, Van Ravenstein SX, Vontalge EJ, Greer BH, Heintzman DR, Kavlashvili T, McDonald WH, Rose KL, Eichman BF, Dewar JM. RTEL1 and MCM10 overcome topological stress during vertebrate replication termination. Cell Rep 2023; 42:112109. [PMID: 36807139 PMCID: PMC10432576 DOI: 10.1016/j.celrep.2023.112109] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 11/30/2022] [Accepted: 01/30/2023] [Indexed: 02/19/2023] Open
Abstract
Topological stress can cause converging replication forks to stall during termination of vertebrate DNA synthesis. However, replication forks ultimately overcome fork stalling, suggesting that alternative mechanisms of termination exist. Using proteomics in Xenopus egg extracts, we show that the helicase RTEL1 and the replisome protein MCM10 are highly enriched on chromatin during fork convergence and are crucially important for fork convergence under conditions of topological stress. RTEL1 and MCM10 cooperate to promote fork convergence and do not impact topoisomerase activity but do promote fork progression through a replication barrier. Thus, RTEL1 and MCM10 play a general role in promoting progression of stalled forks, including when forks stall during termination. Our data reveal an alternate mechanism of termination involving RTEL1 and MCM10 that can be used to complete DNA synthesis under conditions of topological stress.
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Affiliation(s)
- Lillian V Campos
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | | | - Emma J Vontalge
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Briana H Greer
- Department of Biological Sciences and Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA
| | - Darren R Heintzman
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Tamar Kavlashvili
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - W Hayes McDonald
- Department of Biochemistry and Mass Spectrometry Research Center, Vanderbilt University, Nashville, TN 37232, USA
| | - Kristie Lindsey Rose
- Department of Biochemistry and Mass Spectrometry Research Center, Vanderbilt University, Nashville, TN 37232, USA
| | - Brandt F Eichman
- Department of Biological Sciences and Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA
| | - James M Dewar
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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13
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Kondaka K, Gabriel I. Targeting DNA Topoisomerase II in Antifungal Chemotherapy. Molecules 2022; 27:molecules27227768. [PMID: 36431868 PMCID: PMC9698242 DOI: 10.3390/molecules27227768] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022] Open
Abstract
Topoisomerase inhibitors have been in use clinically for the treatment of several diseases for decades. Although those enzymes are significant molecular targets in antibacterial and anticancer chemotherapy very little is known about the possibilities to target fungal topoisomerase II (topo II). Raising concern for the fungal infections, lack of effective drugs and a phenomenon of multidrug resistance underlie a strong need to expand the range of therapeutic options. In this review paper, we discussed the usefulness of fungal topo II as a molecular target for new drug discovery. On the basis of previously published data, we described structural and biochemical differences between fungal and human enzymes as well as a molecular basis of differential sensitivity to known anticancer drugs targeting the latter. This review focuses especially on highlighting the differences that may underlie the selectivity of action of new inhibitors. Distinct sites within fungal topo II in comparison with human counterparts are observed and should be further studied to understand the significance of those sites and their possible usage in design of new drugs.
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Affiliation(s)
| | - Iwona Gabriel
- Correspondence: ; Tel.: +48-58-348-6078; Fax: +48-58-347-1144
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14
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Menger KE, Chapman J, Díaz-Maldonado H, Khazeem M, Deen D, Erdinc D, Casement JW, Di Leo V, Pyle A, Rodríguez-Luis A, Cowell I, Falkenberg M, Austin C, Nicholls T. Two type I topoisomerases maintain DNA topology in human mitochondria. Nucleic Acids Res 2022; 50:11154-11174. [PMID: 36215039 PMCID: PMC9638942 DOI: 10.1093/nar/gkac857] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 09/03/2022] [Accepted: 09/26/2022] [Indexed: 11/12/2022] Open
Abstract
Genetic processes require the activity of multiple topoisomerases, essential enzymes that remove topological tension and intermolecular linkages in DNA. We have investigated the subcellular localisation and activity of the six human topoisomerases with a view to understanding the topological maintenance of human mitochondrial DNA. Our results indicate that mitochondria contain two topoisomerases, TOP1MT and TOP3A. Using molecular, genomic and biochemical methods we find that both proteins contribute to mtDNA replication, in addition to the decatenation role of TOP3A, and that TOP1MT is stimulated by mtSSB. Loss of TOP3A or TOP1MT also dysregulates mitochondrial gene expression, and both proteins promote transcription elongation in vitro. We find no evidence for TOP2 localisation to mitochondria, and TOP2B knockout does not affect mtDNA maintenance or expression. Our results suggest a division of labour between TOP3A and TOP1MT in mtDNA topology control that is required for the proper maintenance and expression of human mtDNA.
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Affiliation(s)
- Katja E Menger
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - James Chapman
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Héctor Díaz-Maldonado
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, PO Box 440, 405 30 Gothenburg, Sweden
| | - Mushtaq M Khazeem
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Dasha Deen
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Direnis Erdinc
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, PO Box 440, 405 30 Gothenburg, Sweden
| | - John W Casement
- Bioinformatics Support Unit, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Valeria Di Leo
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Angela Pyle
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Alejandro Rodríguez-Luis
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Ian G Cowell
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Maria Falkenberg
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, PO Box 440, 405 30 Gothenburg, Sweden
| | - Caroline A Austin
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Thomas J Nicholls
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
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15
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Dalvie ED, Stacy JC, Neuman KC, Osheroff N. Recognition of DNA Supercoil Handedness during Catenation Catalyzed by Type II Topoisomerases. Biochemistry 2022; 61:2148-2158. [PMID: 36122251 PMCID: PMC9548324 DOI: 10.1021/acs.biochem.2c00370] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although the presence of catenanes (i.e., intermolecular tangles) in chromosomal DNA stabilizes interactions between daughter chromosomes, a lack of resolution can have serious consequences for genomic stability. In all species, from bacteria to humans, type II topoisomerases are the enzymes primarily responsible for catenating/decatenating DNA. DNA topology has a profound influence on the rate at which these enzymes alter the superhelical state of the double helix. Therefore, the effect of supercoil handedness on the ability of human topoisomerase IIα and topoisomerase IIβ and bacterial topoisomerase IV to catenate DNA was examined. Topoisomerase IIα preferentially catenated negatively supercoiled over positively supercoiled substrates. This is opposite to its preference for relaxing (i.e., removing supercoils from) DNA and may prevent the enzyme from tangling the double helix ahead of replication forks and transcription complexes. The ability of topoisomerase IIα to recognize DNA supercoil handedness during catenation resides in its C-terminal domain. In contrast to topoisomerase IIα, topoisomerase IIβ displayed little ability to distinguish DNA geometry during catenation. Topoisomerase IV from three bacterial species preferentially catenated positively supercoiled substrates. This may not be an issue, as these enzymes work primarily behind replication forks. Finally, topoisomerase IIα and topoisomerase IV maintain lower levels of covalent enzyme-cleaved DNA intermediates with catenated over monomeric DNA. This allows these enzymes to perform their cellular functions in a safer manner, as catenated daughter chromosomes may be subject to stress generated by the mitotic spindle that could lead to irreversible DNA cleavage.
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Affiliation(s)
- Esha D. Dalvie
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, United States
| | - Jordan C. Stacy
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, United States
| | - Keir C. Neuman
- Laboratory of Single Molecule Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20982, United States
| | - Neil Osheroff
- Departments of Biochemistry and Medicine (Hematology/Oncology), Vanderbilt University School of Medicine, Nashville, TN 37232, United States; VA Tennessee Valley Healthcare System, Nashville, TN 37212, United States
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16
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Qin S, Yuan Y, Huang X, Tan Z, Hu X, Liu H, Pu Y, Ding YQ, Su Z, He C. Topoisomerase IIA in adult NSCs regulates SVZ neurogenesis by transcriptional activation of Usp37. Nucleic Acids Res 2022; 50:9319-9338. [PMID: 36029179 PMCID: PMC9458435 DOI: 10.1093/nar/gkac731] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 07/31/2022] [Accepted: 08/14/2022] [Indexed: 01/27/2023] Open
Abstract
Topoisomerase IIA (TOP2a) has traditionally been known as an important nuclear enzyme that resolves entanglements and relieves torsional stress of DNA double strands. However, its function in genomic transcriptional regulation remains largely unknown, especially during adult neurogenesis. Here, we show that TOP2a is preferentially expressed in neurogenic niches in the brain of adult mice, such as the subventricular zone (SVZ). Conditional knockout of Top2a in adult neural stem cells (NSCs) of the SVZ significantly inhibits their self-renewal and proliferation, and ultimately reduces neurogenesis. To gain insight into the molecular mechanisms by which TOP2a regulates adult NSCs, we perform RNA-sequencing (RNA-Seq) plus chromatin immunoprecipitation sequencing (ChIP-Seq) and identify ubiquitin-specific protease 37 (Usp37) as a direct TOP2a target gene. Importantly, overexpression of Usp37 is sufficient to rescue the impaired self-renewal ability of adult NSCs caused by Top2a knockdown. Taken together, this proof-of-principle study illustrates a TOP2a/Usp37-mediated novel molecular mechanism in adult neurogenesis, which will significantly expand our understanding of the function of topoisomerase in the adult brain.
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Affiliation(s)
- Shangyao Qin
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Naval Medical University, Shanghai 200433, China
| | - Yimin Yuan
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Naval Medical University, Shanghai 200433, China
| | - Xiao Huang
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Naval Medical University, Shanghai 200433, China
| | - Zijian Tan
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Naval Medical University, Shanghai 200433, China
| | - Xin Hu
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Naval Medical University, Shanghai 200433, China
| | - Hong Liu
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Naval Medical University, Shanghai 200433, China
| | - Yingyan Pu
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Naval Medical University, Shanghai 200433, China
| | - Yu-qiang Ding
- Department of Laboratory Animal Science, and State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai 200032, China
| | - Zhida Su
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Naval Medical University, Shanghai 200433, China
| | - Cheng He
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Naval Medical University, Shanghai 200433, China
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17
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Lockwood N, Martini S, Lopez-Pardo A, Deiss K, Segeren HA, Semple RK, Collins I, Repana D, Cobbaut M, Soliman T, Ciccarelli F, Parker PJ. Genome-Protective Topoisomerase 2a-Dependent G2 Arrest Requires p53 in hTERT-Positive Cancer Cells. Cancer Res 2022; 82:1762-1773. [PMID: 35247890 PMCID: PMC7612711 DOI: 10.1158/0008-5472.can-21-1785] [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: 06/03/2021] [Revised: 02/01/2022] [Accepted: 02/25/2022] [Indexed: 11/16/2022]
Abstract
Topoisomerase 2a (Topo2a)-dependent G2 arrest engenders faithful segregation of sister chromatids, yet in certain tumor cell lines where this arrest is dysfunctional, a PKCε-dependent failsafe pathway can be triggered. Here we elaborate on recent advances in understanding the underlying mechanisms associated with this G2 arrest by determining that p53-p21 signaling is essential for efficient arrest in cell lines, in patient-derived cells, and in colorectal cancer organoids. Regulation of this p53 axis required the SMC5/6 complex, which is distinct from the p53 pathways observed in the DNA damage response. Topo2a inhibition specifically during S phase did not trigger G2 arrest despite affecting completion of DNA replication. Moreover, in cancer cells reliant upon the alternative lengthening of telomeres (ALT) mechanism, a distinct form of Topo2a-dependent, p53-independent G2 arrest was found to be mediated by BLM and Chk1. Importantly, the previously described PKCε-dependent mitotic failsafe was engaged in hTERT-positive cells when Topo2a-dependent G2 arrest was dysfunctional and where p53 was absent, but not in cells dependent on the ALT mechanism. In PKCε knockout mice, p53 deletion elicited tumors were less aggressive than in PKCε-replete animals and exhibited a distinct pattern of chromosomal rearrangements. This evidence suggests the potential of exploiting synthetic lethality in arrest-defective hTERT-positive tumors through PKCε-directed therapeutic intervention. SIGNIFICANCE The identification of a requirement for p53 in stringent Topo2a-dependent G2 arrest and engagement of PKCε failsafe pathways in arrest-defective hTERT-positive cells provides a therapeutic opportunity to induce selective synthetic lethality.
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Affiliation(s)
- Nicola Lockwood
- Protein Phosphorylation Laboratory, The Francis Crick Institute, 1 Midland Road, London, UK
| | - Silvia Martini
- Protein Phosphorylation Laboratory, The Francis Crick Institute, 1 Midland Road, London, UK
| | - Ainara Lopez-Pardo
- Protein Phosphorylation Laboratory, The Francis Crick Institute, 1 Midland Road, London, UK
| | - Katharina Deiss
- Protein Phosphorylation Laboratory, The Francis Crick Institute, 1 Midland Road, London, UK
| | - Hendrika A Segeren
- Protein Phosphorylation Laboratory, The Francis Crick Institute, 1 Midland Road, London, UK
| | - Robert K Semple
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Ian Collins
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, UK
| | - Dimitra Repana
- Cancer Systems Biology Laboratory, The Francis Crick Institute, London, UK.,School of Cancer and Pharmaceutical Sciences King's College London, New Hunt's House, Guy's Campus, London, UK
| | - Mathias Cobbaut
- Protein Phosphorylation Laboratory, The Francis Crick Institute, 1 Midland Road, London, UK
| | - Tanya Soliman
- Barts Cancer Institute, Queen Mary University London, Charterhouse Square, London, UK
| | - Francesca Ciccarelli
- Cancer Systems Biology Laboratory, The Francis Crick Institute, London, UK.,School of Cancer and Pharmaceutical Sciences King's College London, New Hunt's House, Guy's Campus, London, UK
| | - Peter J Parker
- Protein Phosphorylation Laboratory, The Francis Crick Institute, 1 Midland Road, London, UK.,School of Cancer and Pharmaceutical Sciences King's College London, New Hunt's House, Guy's Campus, London, UK
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18
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Muturi E, Meng F, Liu H, Jiang M, Wei H, Yang H. Comprehensive Analysis of G-Quadruplexes in African Swine Fever Virus Genome Reveals Potential Antiviral Targets by G-Quadruplex Stabilizers. Front Microbiol 2022; 12:798431. [PMID: 34975822 PMCID: PMC8718096 DOI: 10.3389/fmicb.2021.798431] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 11/11/2021] [Indexed: 12/24/2022] Open
Abstract
African Swine Fever Virus (ASFV), a lethal hemorrhagic fever of the swine, poses a major threat to the world's swine population and has so far resulted in devastating socio-economic consequences. The situation is further compounded by the lack of an approved vaccine or antiviral drug. Herein, we investigated a novel anti-ASFV approach by targeting G-Quadruplexes (G4s) in the viral genome. Bioinformatics analysis of putative G-quadruplex-forming sequences (PQSs) in the genome of ASFV BA71V strain revealed 317 PQSs on the forward strand and 322 PQSs on the reverse strand of the viral genome, translating to a density of 3.82 PQSs/kb covering 9.52% of the entire genome, which means that 85% of genes in the ASFV genome have at least 1 PQS on either strand. Biochemical characterization showed that 8 out of 13 conserved PQSs could form stable G4s in the presence of K+, and 4 of them could be stabilized by G4 ligands, N-Methyl Mesoporphyrin (NMM), and pyridostatin (PDS) in vitro. An enhanced green fluorescent protein (EGFP)-based reporter system revealed that the expression of two G4-containing genes, i.e., P1192R and D117L, could be significantly suppressed by NMM and PDS in 293T cells. In addition, a virus infection model showed that NMM could inhibit the replication of ASFV in Porcine Alveolar Macrophages (PAM) cells with an EC50 value of 1.16 μM. Altogether, the present study showed that functional PQSs existent in the promoters, CDS, 3' and 5' UTRs of the ASFV genome could be stabilized by G4 ligands, such as NMM and PDS, and could serve as potential targets for antivirals.
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Affiliation(s)
- Elishiba Muturi
- CAS Key Laboratory of Special Pathogens and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Fei Meng
- CAS Key Laboratory of Special Pathogens and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Huan Liu
- CAS Key Laboratory of Special Pathogens and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Mengwei Jiang
- CAS Key Laboratory of Special Pathogens and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Hongping Wei
- CAS Key Laboratory of Special Pathogens and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Hang Yang
- CAS Key Laboratory of Special Pathogens and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
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19
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Menger KE, Rodríguez-Luis A, Chapman J, Nicholls TJ. Controlling the topology of mammalian mitochondrial DNA. Open Biol 2021; 11:210168. [PMID: 34547213 PMCID: PMC8455175 DOI: 10.1098/rsob.210168] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The genome of mitochondria, called mtDNA, is a small circular DNA molecule present at thousands of copies per human cell. MtDNA is packaged into nucleoprotein complexes called nucleoids, and the density of mtDNA packaging affects mitochondrial gene expression. Genetic processes such as transcription, DNA replication and DNA packaging alter DNA topology, and these topological problems are solved by a family of enzymes called topoisomerases. Within mitochondria, topoisomerases are involved firstly in the regulation of mtDNA supercoiling and secondly in disentangling interlinked mtDNA molecules following mtDNA replication. The loss of mitochondrial topoisomerase activity leads to defects in mitochondrial function, and variants in the dual-localized type IA topoisomerase TOP3A have also been reported to cause human mitochondrial disease. We review the current knowledge on processes that alter mtDNA topology, how mtDNA topology is modulated by the action of topoisomerases, and the consequences of altered mtDNA topology for mitochondrial function and human health.
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Affiliation(s)
- Katja E. Menger
- Wellcome Centre for Mitochondrial Research, Biosciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Alejandro Rodríguez-Luis
- Wellcome Centre for Mitochondrial Research, Biosciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - James Chapman
- Wellcome Centre for Mitochondrial Research, Biosciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Thomas J. Nicholls
- Wellcome Centre for Mitochondrial Research, Biosciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
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20
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Topoisomerase II deficiency leads to a postreplicative structural shift in all Saccharomyces cerevisiae chromosomes. Sci Rep 2021; 11:14940. [PMID: 34294749 PMCID: PMC8298500 DOI: 10.1038/s41598-021-93875-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 07/01/2021] [Indexed: 02/06/2023] Open
Abstract
The key role of Topoisomerase II (Top2) is the removal of topological intertwines between sister chromatids. In yeast, inactivation of Top2 brings about distinct cell cycle responses. In the case of the conditional top2-5 allele, interphase and mitosis progress on schedule but cells suffer from a chromosome segregation catastrophe. We here show that top2-5 chromosomes fail to enter a Pulsed-Field Gel Electrophoresis (PFGE) in the first cell cycle, a behavior traditionally linked to the presence of replication and recombination intermediates. We distinguished two classes of affected chromosomes: the rDNA-bearing chromosome XII, which fails to enter a PFGE at the beginning of S-phase, and all the other chromosomes, which fail at a postreplicative stage. In synchronously cycling cells, this late PFGE retention is observed in anaphase; however, we demonstrate that this behavior is independent of cytokinesis, stabilization of anaphase bridges, spindle pulling forces and, probably, anaphase onset. Strikingly, once the PFGE retention has occurred it becomes refractory to Top2 re-activation. DNA combing, two-dimensional electrophoresis, genetic analyses, and GFP-tagged DNA damage markers suggest that neither recombination intermediates nor unfinished replication account for the postreplicative PFGE shift, which is further supported by the fact that the shift does not trigger the G2/M checkpoint. We propose that the absence of Top2 activity leads to a general chromosome structural/topological change in mitosis.
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21
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Xia Y. The Fate of Two Unstoppable Trains After Arriving Destination: Replisome Disassembly During DNA Replication Termination. Front Cell Dev Biol 2021; 9:658003. [PMID: 34368118 PMCID: PMC8335557 DOI: 10.3389/fcell.2021.658003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 06/14/2021] [Indexed: 12/30/2022] Open
Abstract
In eukaryotes, the perfect duplication of the chromosomes is executed by a dynamic molecular machine called the replisome. As a key step to finishing DNA replication, replisome disassembly is triggered by ubiquitylation of the MCM7 subunit of the helicase complex CMG. Afterwards, the CDC48/p97 "unfoldase" is recruited to the ubiquitylated helicase to unfold MCM7 and disassemble the replisome. Here we summarise recently discovered mechanisms of replisome disassembly that are likely to be broadly conserved in eukaryotes. We also discuss two crucial questions that remain to be explored further in the future. Firstly, how is CMG ubiquitylation repressed by the replication fork throughout elongation? Secondly, what is the biological significance of replisome disassembly and what are the consequences of failing to ubiquitylate and disassemble the CMG helicase?
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Affiliation(s)
- Yisui Xia
- The MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee, United Kingdom
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22
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McKie SJ, Neuman KC, Maxwell A. DNA topoisomerases: Advances in understanding of cellular roles and multi-protein complexes via structure-function analysis. Bioessays 2021; 43:e2000286. [PMID: 33480441 PMCID: PMC7614492 DOI: 10.1002/bies.202000286] [Citation(s) in RCA: 106] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/06/2020] [Accepted: 12/17/2020] [Indexed: 12/15/2022]
Abstract
DNA topoisomerases, capable of manipulating DNA topology, are ubiquitous and indispensable for cellular survival due to the numerous roles they play during DNA metabolism. As we review here, current structural approaches have revealed unprecedented insights into the complex DNA-topoisomerase interaction and strand passage mechanism, helping to advance our understanding of their activities in vivo. This has been complemented by single-molecule techniques, which have facilitated the detailed dissection of the various topoisomerase reactions. Recent work has also revealed the importance of topoisomerase interactions with accessory proteins and other DNA-associated proteins, supporting the idea that they often function as part of multi-enzyme assemblies in vivo. In addition, novel topoisomerases have been identified and explored, such as topo VIII and Mini-A. These new findings are advancing our understanding of DNA-related processes and the vital functions topos fulfil, demonstrating their indispensability in virtually every aspect of DNA metabolism.
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Affiliation(s)
- Shannon J. McKie
- Department Biological Chemistry, John Innes Centre, Norwich, UK
- Laboratory of Single Molecule Biophysics, NHLBI, Bethesda, Maryland, USA
| | - Keir C. Neuman
- Laboratory of Single Molecule Biophysics, NHLBI, Bethesda, Maryland, USA
| | - Anthony Maxwell
- Department Biological Chemistry, John Innes Centre, Norwich, UK
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23
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Johansson M, Azuma Y, Clarke DJ. Role of Aurora B and Haspin kinases in the metaphase Topoisomerase II checkpoint. Cell Cycle 2021; 20:345-352. [PMID: 33459116 DOI: 10.1080/15384101.2021.1875671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
DNA Topoisomerase II (TopoII) uses ATP hydrolysis to decatenate chromosomes so that sister chromatids can faithfully segregate in mitosis. When the TopoII enzyme cycle stalls due to failed ATP hydrolysis, the onset of anaphase is delayed, presumably to allow extra time for decatenation to be completed. Recent evidence revealed that, unlike the spindle assembly checkpoint, this TopoII checkpoint response requires Aurora B and Haspin kinases and is triggered by SUMOylation of the C-terminal domain of TopoII.
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Affiliation(s)
- M Johansson
- Department of Genetics, Cell Biology & Development, University of Minnesota , Minneapolis, MN, USA
| | - Y Azuma
- Department of Molecular Biosciences, University of Kansas , Lawrence, KS, USA
| | - D J Clarke
- Department of Genetics, Cell Biology & Development, University of Minnesota , Minneapolis, MN, USA
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24
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Pérez-Arnaiz P, Dattani A, Smith V, Allers T. Haloferax volcanii-a model archaeon for studying DNA replication and repair. Open Biol 2020; 10:200293. [PMID: 33259746 PMCID: PMC7776575 DOI: 10.1098/rsob.200293] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 11/09/2020] [Indexed: 12/16/2022] Open
Abstract
The tree of life shows the relationship between all organisms based on their common ancestry. Until 1977, it comprised two major branches: prokaryotes and eukaryotes. Work by Carl Woese and other microbiologists led to the recategorization of prokaryotes and the proposal of three primary domains: Eukarya, Bacteria and Archaea. Microbiological, genetic and biochemical techniques were then needed to study the third domain of life. Haloferax volcanii, a halophilic species belonging to the phylum Euryarchaeota, has provided many useful tools to study Archaea, including easy culturing methods, genetic manipulation and phenotypic screening. This review will focus on DNA replication and DNA repair pathways in H. volcanii, how this work has advanced our knowledge of archaeal cellular biology, and how it may deepen our understanding of bacterial and eukaryotic processes.
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Affiliation(s)
| | | | | | - Thorsten Allers
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, UK
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25
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Heintzman DR, Campos LV, Byl JAW, Osheroff N, Dewar JM. Topoisomerase II Is Crucial for Fork Convergence during Vertebrate Replication Termination. Cell Rep 2020; 29:422-436.e5. [PMID: 31597101 PMCID: PMC6919565 DOI: 10.1016/j.celrep.2019.08.097] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 07/27/2019] [Accepted: 08/28/2019] [Indexed: 11/28/2022] Open
Abstract
Termination of DNA replication occurs when two replication forks converge upon the same stretch of DNA. Resolution of topological stress by topoisomerases is crucial for fork convergence in bacteria and viruses, but it is unclear whether similar mechanisms operate during vertebrate termination. Using Xenopus egg extracts, we show that topoisomerase II (Top2) resolves topological stress to prevent converging forks from stalling during termination. Under these conditions, stalling arises due to an inability to unwind the final stretch of DNA ahead of each fork. By promoting fork convergence, Top2 facilitates all downstream events of termination. Converging forks ultimately overcome stalling independently of Top2, indicating that additional mechanisms support fork convergence. Top2 acts throughout replication to prevent the accumulation of topological stress that would otherwise stall converging forks. Thus, termination poses evolutionarily conserved topological problems that can be mitigated by careful execution of the earlier stages of replication.
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Affiliation(s)
- Darren R Heintzman
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Lillian V Campos
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Jo Ann W Byl
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Neil Osheroff
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Medicine (Hematology, Oncology), Vanderbilt University School of Medicine, Nashville, TN 37232, USA; VA Tennessee Valley Healthcare System, Nashville, TN 37212, USA
| | - James M Dewar
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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26
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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: 29] [Impact Index Per Article: 5.8] [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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27
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Chromatin Architectural Factors as Safeguards against Excessive Supercoiling during DNA Replication. Int J Mol Sci 2020; 21:ijms21124504. [PMID: 32599919 PMCID: PMC7349988 DOI: 10.3390/ijms21124504] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 06/17/2020] [Accepted: 06/23/2020] [Indexed: 12/21/2022] Open
Abstract
Key DNA transactions, such as genome replication and transcription, rely on the speedy translocation of specialized protein complexes along a double-stranded, right-handed helical template. Physical tethering of these molecular machines during translocation, in conjunction with their internal architectural features, generates DNA topological strain in the form of template supercoiling. It is known that the build-up of transient excessive supercoiling poses severe threats to genome function and stability and that highly specialized enzymes—the topoisomerases (TOP)—have evolved to mitigate these threats. Furthermore, due to their intracellular abundance and fast supercoil relaxation rates, it is generally assumed that these enzymes are sufficient in coping with genome-wide bursts of excessive supercoiling. However, the recent discoveries of chromatin architectural factors that play important accessory functions have cast reasonable doubts on this concept. Here, we reviewed the background of these new findings and described emerging models of how these accessory factors contribute to supercoil homeostasis. We focused on DNA replication and the generation of positive (+) supercoiling in front of replisomes, where two accessory factors—GapR and HMGA2—from pro- and eukaryotic cells, respectively, appear to play important roles as sinks for excessive (+) supercoiling by employing a combination of supercoil constrainment and activation of topoisomerases. Looking forward, we expect that additional factors will be identified in the future as part of an expanding cellular repertoire to cope with bursts of topological strain. Furthermore, identifying antagonists that target these accessory factors and work synergistically with clinically relevant topoisomerase inhibitors could become an interesting novel strategy, leading to improved treatment outcomes.
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28
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The African Swine Fever Virus (ASFV) Topoisomerase II as a Target for Viral Prevention and Control. Vaccines (Basel) 2020; 8:vaccines8020312. [PMID: 32560397 PMCID: PMC7350233 DOI: 10.3390/vaccines8020312] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/12/2020] [Accepted: 06/14/2020] [Indexed: 12/18/2022] Open
Abstract
African swine fever (ASF) is, once more, spreading throughout the world. After its recent reintroduction in Georgia, it quickly reached many neighboring countries in Eastern Europe. It was also detected in Asia, infecting China, the world's biggest pig producer, and spreading to many of the surrounding countries. Without any vaccine or effective treatment currently available, new strategies for the control of the disease are mandatory. Its etiological agent, the African swine fever virus (ASFV), has been shown to code for a type II DNA topoisomerase. These are enzymes capable of modulating the topology of DNA molecules, known to be essential in unicellular and multicellular organisms, and constitute targets in antibacterial and anti-cancer treatments. In this review, we summarize most of what is known about this viral enzyme, pP1192R, and discuss about its possible role(s) during infection. Given the essential role of type II topoisomerases in cells, the data so far suggest that pP1192R is likely to be equally essential for the virus and thus a promising target for the elaboration of a replication-defective virus, which could provide the basis for an effective vaccine. Furthermore, the use of inhibitors could be considered to control the spread of the infection during outbreaks and therefore limit the spreading of the disease.
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29
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Le TT, Gao X, Park SH, Lee J, Inman JT, Lee JH, Killian JL, Badman RP, Berger JM, Wang MD. Synergistic Coordination of Chromatin Torsional Mechanics and Topoisomerase Activity. Cell 2020; 179:619-631.e15. [PMID: 31626768 PMCID: PMC6899335 DOI: 10.1016/j.cell.2019.09.034] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 06/16/2019] [Accepted: 09/24/2019] [Indexed: 12/23/2022]
Abstract
DNA replication in eukaryotes generates DNA supercoiling, which may intertwine (braid) daughter chromatin fibers to form precatenanes, posing topological challenges during chromosome segregation. The mechanisms that limit precatenane formation remain unclear. By making direct torque measurements, we demonstrate that the intrinsic mechanical properties of chromatin play a fundamental role in dictating precatenane formation and regulating chromatin topology. Whereas a single chromatin fiber is torsionally soft, a braided fiber is torsionally stiff, indicating that supercoiling on chromatin substrates is preferentially directed in front of the fork during replication. We further show that topoisomerase II relaxation displays a strong preference for a single chromatin fiber over a braided fiber. These results suggest a synergistic coordination-the mechanical properties of chromatin inherently suppress precatenane formation during replication elongation by driving DNA supercoiling ahead of the fork, where supercoiling is more efficiently removed by topoisomerase II. VIDEO ABSTRACT.
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Affiliation(s)
- Tung T Le
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA; Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Xiang Gao
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA; Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Seong Ha Park
- Biophysics Program, Cornell University, Ithaca, NY 14853, USA
| | - Jaeyoon Lee
- Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - James T Inman
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA; Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Joyce H Lee
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jessica L Killian
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA; Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Ryan P Badman
- Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - James M Berger
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Michelle D Wang
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA; Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA.
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30
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Minchell NE, Keszthelyi A, Baxter J. Cohesin Causes Replicative DNA Damage by Trapping DNA Topological Stress. Mol Cell 2020; 78:739-751.e8. [PMID: 32259483 PMCID: PMC7242899 DOI: 10.1016/j.molcel.2020.03.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 02/12/2020] [Accepted: 03/09/2020] [Indexed: 12/25/2022]
Abstract
DNA topological stress inhibits DNA replication fork (RF) progression and contributes to DNA replication stress. In Saccharomyces cerevisiae, we demonstrate that centromeric DNA and the rDNA array are especially vulnerable to DNA topological stress during replication. The activity of the SMC complexes cohesin and condensin are linked to both the generation and repair of DNA topological-stress-linked damage in these regions. At cohesin-enriched centromeres, cohesin activity causes the accumulation of DNA damage, RF rotation, and pre-catenation, confirming that cohesin-dependent DNA topological stress impacts on normal replication progression. In contrast, at the rDNA, cohesin and condensin activity inhibit the repair of damage caused by DNA topological stress. We propose that, as well as generally acting to ensure faithful genetic inheritance, SMCs can disrupt genome stability by trapping DNA topological stress.
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Affiliation(s)
- Nicola Elizabeth Minchell
- Genome Damage and Stability Centre, School of Life Sciences, Science Park Road, University of Sussex, Falmer, Brighton, East Sussex BN1 9RQ, UK
| | - Andrea Keszthelyi
- Genome Damage and Stability Centre, School of Life Sciences, Science Park Road, University of Sussex, Falmer, Brighton, East Sussex BN1 9RQ, UK
| | - Jonathan Baxter
- Genome Damage and Stability Centre, School of Life Sciences, Science Park Road, University of Sussex, Falmer, Brighton, East Sussex BN1 9RQ, UK.
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31
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Umbreit NT, Zhang CZ, Lynch LD, Blaine LJ, Cheng AM, Tourdot R, Sun L, Almubarak HF, Judge K, Mitchell TJ, Spektor A, Pellman D. Mechanisms generating cancer genome complexity from a single cell division error. Science 2020; 368:eaba0712. [PMID: 32299917 PMCID: PMC7347108 DOI: 10.1126/science.aba0712] [Citation(s) in RCA: 281] [Impact Index Per Article: 56.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 03/04/2020] [Indexed: 12/12/2022]
Abstract
The chromosome breakage-fusion-bridge (BFB) cycle is a mutational process that produces gene amplification and genome instability. Signatures of BFB cycles can be observed in cancer genomes alongside chromothripsis, another catastrophic mutational phenomenon. We explain this association by elucidating a mutational cascade that is triggered by a single cell division error-chromosome bridge formation-that rapidly increases genomic complexity. We show that actomyosin forces are required for initial bridge breakage. Chromothripsis accumulates, beginning with aberrant interphase replication of bridge DNA. A subsequent burst of DNA replication in the next mitosis generates extensive DNA damage. During this second cell division, broken bridge chromosomes frequently missegregate and form micronuclei, promoting additional chromothripsis. We propose that iterations of this mutational cascade generate the continuing evolution and subclonal heterogeneity characteristic of many human cancers.
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Affiliation(s)
- Neil T Umbreit
- Howard Hughes Medical Institute, Chevy Chase, MD, USA.
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Cheng-Zhong Zhang
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, USA.
- Department of Data Sciences, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Luke D Lynch
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Logan J Blaine
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Anna M Cheng
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Richard Tourdot
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, USA
- Department of Data Sciences, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Lili Sun
- Single-Cell Sequencing Program, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Hannah F Almubarak
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, USA
- Department of Data Sciences, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Kim Judge
- Wellcome Sanger Institute, Hinxton, Cambridgeshire CB10 1SA, UK
| | - Thomas J Mitchell
- Wellcome Sanger Institute, Hinxton, Cambridgeshire CB10 1SA, UK
- Cambridge University Hospitals NHS Foundation Trust, Cambridge CB2 0QQ, UK
| | - Alexander Spektor
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - David Pellman
- Howard Hughes Medical Institute, Chevy Chase, MD, USA.
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
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32
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Abstract
The double-helical structure of genomic DNA is both elegant and functional in that it serves both to protect vulnerable DNA bases and to facilitate DNA replication and compaction. However, these design advantages come at the cost of having to evolve and maintain a cellular machinery that can manipulate a long polymeric molecule that readily becomes topologically entangled whenever it has to be opened for translation, replication, or repair. If such a machinery fails to eliminate detrimental topological entanglements, utilization of the information stored in the DNA double helix is compromised. As a consequence, the use of B-form DNA as the carrier of genetic information must have co-evolved with a means to manipulate its complex topology. This duty is performed by DNA topoisomerases, which therefore are, unsurprisingly, ubiquitous in all kingdoms of life. In this review, we focus on how DNA topoisomerases catalyze their impressive range of DNA-conjuring tricks, with a particular emphasis on DNA topoisomerase III (TOP3). Once thought to be the most unremarkable of topoisomerases, the many lives of these type IA topoisomerases are now being progressively revealed. This research interest is driven by a realization that their substrate versatility and their ability to engage in intimate collaborations with translocases and other DNA-processing enzymes are far more extensive and impressive than was thought hitherto. This, coupled with the recent associations of TOP3s with developmental and neurological pathologies in humans, is clearly making us reconsider their undeserved reputation as being unexceptional enzymes.
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Affiliation(s)
- Anna H Bizard
- Center for Chromosome Stability and Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark
| | - Ian D Hickson
- Center for Chromosome Stability and Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark
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33
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Ramos-Pérez C, Dominska M, Anaissi-Afonso L, Cazorla-Rivero S, Quevedo O, Lorenzo-Castrillejo I, Petes TD, Machín F. Cytological and genetic consequences for the progeny of a mitotic catastrophe provoked by Topoisomerase II deficiency. Aging (Albany NY) 2019; 11:11686-11721. [PMID: 31812950 PMCID: PMC6932922 DOI: 10.18632/aging.102573] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 11/24/2019] [Indexed: 02/07/2023]
Abstract
Topoisomerase II (Top2) removes topological linkages between replicated chromosomes. Top2 inhibition leads to mitotic catastrophe (MC) when cells unsuccessfully try to split their genetic material between the two daughter cells. Herein, we have characterized the fate of these daughter cells in the budding yeast. Clonogenic and microcolony experiments, in combination with vital and apoptotic stains, showed that 75% of daughter cells become senescent in the short term; they are unable to divide but remain alive. Decline in cell vitality then occurred, yet slowly, uncoordinatedly when comparing pairs of daughters, and independently of the cell death mediator Mca1/Yca1. Furthermore, we showed that senescence can be modulated by ploidy, suggesting that gross chromosome imbalances during segregation may account for this phenotype. Indeed, we found that diploid long-term survivors of the MC are prone to genomic imbalances such as trisomies, uniparental disomies and terminal loss of heterozygosity (LOH), the latter affecting the longest chromosome arms.
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Affiliation(s)
- Cristina Ramos-Pérez
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Spain.,Escuela de Doctorado y Estudios de Postgrado, Universidad de La Laguna, Tenerife, Spain.,Present address: BenchSci Analytics Inc., Toronto, Canada
| | - Margaret Dominska
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Laura Anaissi-Afonso
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Spain.,Escuela de Doctorado y Estudios de Postgrado, Universidad de La Laguna, Tenerife, Spain
| | - Sara Cazorla-Rivero
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Spain.,Escuela de Doctorado y Estudios de Postgrado, Universidad de La Laguna, Tenerife, Spain
| | - Oliver Quevedo
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Spain.,Present address: Genomic Integrity Unit, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Isabel Lorenzo-Castrillejo
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Spain
| | - Thomas D Petes
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Félix Machín
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Spain.,Instituto de Tecnologías Biomédicas, Universidad de La Laguna, Tenerife, Spain.,Facultad de Ciencias de la Salud, Universidad Fernando Pessoa Canarias, Las Palmas de Gran Canaria, Spain
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34
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Shyian M, Albert B, Zupan AM, Ivanitsa V, Charbonnet G, Dilg D, Shore D. Fork pausing complex engages topoisomerases at the replisome. Genes Dev 2019; 34:87-98. [PMID: 31805522 PMCID: PMC6938670 DOI: 10.1101/gad.331868.119] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 11/07/2019] [Indexed: 12/22/2022]
Abstract
In this study, Shyian et al. set out to address mechanistically how the evolutionarily conserved fork pausing complex acts at proteinaceous replication fork barriers (RFBs) to promote fork passage and genome stability. Using several molecular and cell-based assays, the authors propose that forks pause at proteinaceous RFBs through a “sTOP” mechanism (“slowing down with topoisomerases I–II”), which also contributes to protecting cells from topoisomerase-blocking agents. Replication forks temporarily or terminally pause at hundreds of hard-to-replicate regions around the genome. A conserved pair of budding yeast replisome components Tof1–Csm3 (fission yeast Swi1–Swi3 and human TIMELESS–TIPIN) act as a “molecular brake” and promote fork slowdown at proteinaceous replication fork barriers (RFBs), while the accessory helicase Rrm3 assists the replisome in removing protein obstacles. Here we show that the Tof1–Csm3 complex promotes fork pausing independently of Rrm3 helicase by recruiting topoisomerase I (Top1) to the replisome. Topoisomerase II (Top2) partially compensates for the pausing decrease in cells when Top1 is lost from the replisome. The C terminus of Tof1 is specifically required for Top1 recruitment to the replisome and fork pausing but not for DNA replication checkpoint (DRC) activation. We propose that forks pause at proteinaceous RFBs through a “sTOP” mechanism (“slowing down with topoisomerases I–II”), which we show also contributes to protecting cells from topoisomerase-blocking agents.
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Affiliation(s)
- Maksym Shyian
- Department of Molecular Biology, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva 4, CH-1211, Switzerland
| | - Benjamin Albert
- Department of Molecular Biology, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva 4, CH-1211, Switzerland
| | - Andreja Moset Zupan
- Department of Molecular Biology, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva 4, CH-1211, Switzerland
| | - Vitalii Ivanitsa
- Department of Molecular Biology, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva 4, CH-1211, Switzerland
| | - Gabriel Charbonnet
- Department of Molecular Biology, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva 4, CH-1211, Switzerland
| | - Daniel Dilg
- Department of Molecular Biology, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva 4, CH-1211, Switzerland
| | - David Shore
- Department of Molecular Biology, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva 4, CH-1211, Switzerland
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35
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Cell Cycle-Dependent Control and Roles of DNA Topoisomerase II. Genes (Basel) 2019; 10:genes10110859. [PMID: 31671531 PMCID: PMC6896119 DOI: 10.3390/genes10110859] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 10/25/2019] [Accepted: 10/28/2019] [Indexed: 12/13/2022] Open
Abstract
Type II topoisomerases are ubiquitous enzymes in all branches of life that can alter DNA superhelicity and unlink double-stranded DNA segments during processes such as replication and transcription. In cells, type II topoisomerases are particularly useful for their ability to disentangle newly-replicated sister chromosomes. Growing lines of evidence indicate that eukaryotic topoisomerase II (topo II) activity is monitored and regulated throughout the cell cycle. Here, we discuss the various roles of topo II throughout the cell cycle, as well as mechanisms that have been found to govern and/or respond to topo II function and dysfunction. Knowledge of how topo II activity is controlled during cell cycle progression is important for understanding how its misregulation can contribute to genetic instability and how modulatory pathways may be exploited to advance chemotherapeutic development.
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36
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Gittens WH, Johnson DJ, Allison RM, Cooper TJ, Thomas H, Neale MJ. A nucleotide resolution map of Top2-linked DNA breaks in the yeast and human genome. Nat Commun 2019; 10:4846. [PMID: 31649282 PMCID: PMC6813358 DOI: 10.1038/s41467-019-12802-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 09/30/2019] [Indexed: 01/01/2023] Open
Abstract
DNA topoisomerases are required to resolve DNA topological stress. Despite this essential role, abortive topoisomerase activity generates aberrant protein-linked DNA breaks, jeopardising genome stability. Here, to understand the genomic distribution and mechanisms underpinning topoisomerase-induced DNA breaks, we map Top2 DNA cleavage with strand-specific nucleotide resolution across the S. cerevisiae and human genomes-and use the meiotic Spo11 protein to validate the broad applicability of this method to explore the role of diverse topoisomerase family members. Our data characterises Mre11-dependent repair in yeast and defines two strikingly different fractions of Top2 activity in humans: tightly localised CTCF-proximal, and broadly distributed transcription-proximal, the latter correlated with gene length and expression. Moreover, single nucleotide accuracy reveals the influence primary DNA sequence has upon Top2 cleavage-distinguishing sites likely to form canonical DNA double-strand breaks (DSBs) from those predisposed to form strand-biased DNA single-strand breaks (SSBs) induced by etoposide (VP16) in vivo.
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Affiliation(s)
- William H Gittens
- Genome Damage and Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK.
| | - Dominic J Johnson
- Genome Damage and Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Rachal M Allison
- Genome Damage and Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Tim J Cooper
- Genome Damage and Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Holly Thomas
- Genome Damage and Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Matthew J Neale
- Genome Damage and Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK.
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37
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Swanston A, Zabrady K, Ferreira HC. The ATP-dependent chromatin remodelling enzyme Uls1 prevents Topoisomerase II poisoning. Nucleic Acids Res 2019; 47:6172-6183. [PMID: 31106359 PMCID: PMC6614809 DOI: 10.1093/nar/gkz362] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 03/29/2019] [Accepted: 04/26/2019] [Indexed: 02/07/2023] Open
Abstract
Topoisomerase II (Top2) is an essential enzyme that decatenates DNA via a transient Top2-DNA covalent intermediate. This intermediate can be stabilized by a class of drugs termed Top2 poisons, resulting in massive DNA damage. Thus, Top2 activity is a double-edged sword that needs to be carefully controlled to maintain genome stability. We show that Uls1, an adenosine triphosphate (ATP)-dependent chromatin remodelling (Snf2) enzyme, can alter Top2 chromatin binding and prevent Top2 poisoning in yeast. Deletion mutants of ULS1 are hypersensitive to the Top2 poison acriflavine (ACF), activating the DNA damage checkpoint. We map Uls1's Top2 interaction domain and show that this, together with its ATPase activity, is essential for Uls1 function. By performing ChIP-seq, we show that ACF leads to a general increase in Top2 binding across the genome. We map Uls1 binding sites and identify tRNA genes as key regions where Uls1 associates after ACF treatment. Importantly, the presence of Uls1 at these sites prevents ACF-dependent Top2 accumulation. Our data reveal the effect of Top2 poisons on the global Top2 binding landscape and highlights the role of Uls1 in antagonizing Top2 function. Remodelling Top2 binding is thus an important new means by which Snf2 enzymes promote genome stability.
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Affiliation(s)
- Amy Swanston
- Biomedical Sciences Research Complex, School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
| | - Katerina Zabrady
- Biomedical Sciences Research Complex, School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
| | - Helder C Ferreira
- Biomedical Sciences Research Complex, School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
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38
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Guérin TM, Béneut C, Barinova N, López V, Lazar-Stefanita L, Deshayes A, Thierry A, Koszul R, Dubrana K, Marcand S. Condensin-Mediated Chromosome Folding and Internal Telomeres Drive Dicentric Severing by Cytokinesis. Mol Cell 2019; 75:131-144.e3. [PMID: 31204167 DOI: 10.1016/j.molcel.2019.05.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 02/12/2019] [Accepted: 05/13/2019] [Indexed: 12/13/2022]
Abstract
In Saccharomyces cerevisiae, dicentric chromosomes stemming from telomere fusions preferentially break at the fusion. This process restores a normal karyotype and protects chromosomes from the detrimental consequences of accidental fusions. Here, we address the molecular basis of this rescue pathway. We observe that tandem arrays tightly bound by the telomere factor Rap1 or a heterologous high-affinity DNA binding factor are sufficient to establish breakage hotspots, mimicking telomere fusions within dicentrics. We also show that condensins generate forces sufficient to rapidly refold dicentrics prior to breakage by cytokinesis and are essential to the preferential breakage at telomere fusions. Thus, the rescue of fused telomeres results from a condensin- and Rap1-driven chromosome folding that favors fusion entrapment where abscission takes place. Because a close spacing between the DNA-bound Rap1 molecules is essential to this process, Rap1 may act by stalling condensins.
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Affiliation(s)
- Thomas M Guérin
- CEA Paris-Saclay, Unité Stabilité Génétique Cellules Souches et Radiations, INSERM U1274, Université de Paris, Université Paris-Saclay, Fontenay-aux-roses, France
| | - Claire Béneut
- CEA Paris-Saclay, Unité Stabilité Génétique Cellules Souches et Radiations, INSERM U1274, Université de Paris, Université Paris-Saclay, Fontenay-aux-roses, France
| | - Natalja Barinova
- CEA Paris-Saclay, Unité Stabilité Génétique Cellules Souches et Radiations, INSERM U1274, Université de Paris, Université Paris-Saclay, Fontenay-aux-roses, France
| | - Virginia López
- CEA Paris-Saclay, Unité Stabilité Génétique Cellules Souches et Radiations, INSERM U1274, Université de Paris, Université Paris-Saclay, Fontenay-aux-roses, France
| | - Luciana Lazar-Stefanita
- Institut Pasteur, Unité Régulation Spatiale des Génomes, CNRS UMR 3525, Sorbonne Université, Paris, France
| | - Alice Deshayes
- CEA Paris-Saclay, Unité Stabilité Génétique Cellules Souches et Radiations, INSERM U1274, Université de Paris, Université Paris-Saclay, Fontenay-aux-roses, France
| | - Agnès Thierry
- Institut Pasteur, Unité Régulation Spatiale des Génomes, CNRS UMR 3525, Sorbonne Université, Paris, France
| | - Romain Koszul
- Institut Pasteur, Unité Régulation Spatiale des Génomes, CNRS UMR 3525, Sorbonne Université, Paris, France
| | - Karine Dubrana
- CEA Paris-Saclay, Unité Stabilité Génétique Cellules Souches et Radiations, INSERM U1274, Université de Paris, Université Paris-Saclay, Fontenay-aux-roses, France
| | - Stéphane Marcand
- CEA Paris-Saclay, Unité Stabilité Génétique Cellules Souches et Radiations, INSERM U1274, Université de Paris, Université Paris-Saclay, Fontenay-aux-roses, France.
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39
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Deegan TD, Baxter J, Ortiz Bazán MÁ, Yeeles JTP, Labib KPM. Pif1-Family Helicases Support Fork Convergence during DNA Replication Termination in Eukaryotes. Mol Cell 2019; 74:231-244.e9. [PMID: 30850330 PMCID: PMC6477153 DOI: 10.1016/j.molcel.2019.01.040] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 11/26/2018] [Accepted: 01/29/2019] [Indexed: 01/21/2023]
Abstract
The convergence of two DNA replication forks creates unique problems during DNA replication termination. In E. coli and SV40, the release of torsional strain by type II topoisomerases is critical for converging replisomes to complete DNA synthesis, but the pathways that mediate fork convergence in eukaryotes are unknown. We studied the convergence of reconstituted yeast replication forks that include all core replisome components and both type I and type II topoisomerases. We found that most converging forks stall at a very late stage, indicating a role for additional factors. We showed that the Pif1 and Rrm3 DNA helicases promote efficient fork convergence and completion of DNA synthesis, even in the absence of type II topoisomerase. Furthermore, Rrm3 and Pif1 are also important for termination of plasmid DNA replication in vivo. These findings identify a eukaryotic pathway for DNA replication termination that is distinct from previously characterized prokaryotic mechanisms.
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Affiliation(s)
- Tom D Deegan
- The MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.
| | - Jonathan Baxter
- Genome Damage and Stability Centre, Department of Life Sciences, University of Sussex, Brighton BN1 9RQ, UK
| | - María Ángeles Ortiz Bazán
- The MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Joseph T P Yeeles
- The MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Karim P M Labib
- The MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.
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40
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Korthout T, Poramba-Liyanage DW, van Kruijsbergen I, Verzijlbergen KF, van Gemert FPA, van Welsem T, van Leeuwen F. Decoding the chromatin proteome of a single genomic locus by DNA sequencing. PLoS Biol 2018; 16:e2005542. [PMID: 30005073 PMCID: PMC6059479 DOI: 10.1371/journal.pbio.2005542] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 07/25/2018] [Accepted: 06/26/2018] [Indexed: 12/14/2022] Open
Abstract
Transcription, replication, and repair involve interactions of specific genomic loci with many different proteins. How these interactions are orchestrated at any given location and under changing cellular conditions is largely unknown because systematically measuring protein-DNA interactions at a specific locus in the genome is challenging. To address this problem, we developed Epi-Decoder, a Tag-chromatin immunoprecipitation-Barcode-Sequencing (TAG-ChIP-Barcode-Seq) technology in budding yeast. Epi-Decoder is orthogonal to proteomics approaches because it does not rely on mass spectrometry (MS) but instead takes advantage of DNA sequencing. Analysis of the proteome of a transcribed locus proximal to an origin of replication revealed more than 400 interacting proteins. Moreover, replication stress induced changes in local chromatin proteome composition prior to local origin firing, affecting replication proteins as well as transcription proteins. Finally, we show that native genomic loci can be decoded by efficient construction of barcode libraries assisted by clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9 (CRISPR/Cas9). Thus, Epi-Decoder is an effective strategy to identify and quantify in an unbiased and systematic manner the proteome of an individual genomic locus by DNA sequencing.
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Affiliation(s)
- Tessy Korthout
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | | | - Ila van Kruijsbergen
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | | | | | - Tibor van Welsem
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Fred van Leeuwen
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, The Netherlands
- * E-mail:
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41
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Castán A, Hernández P, Krimer DB, Schvartzman JB. DNA Catenation Reveals the Dynamics of DNA Topology During Replication. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2017; 1703:75-86. [PMID: 29177734 DOI: 10.1007/978-1-4939-7459-7_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Two-dimensional agarose gel electrophoresis is the method of choice to identify and quantify all the topological forms DNA molecules can adopt in vivo. Here we describe the materials and protocols needed to analyze catenanes, the natural outcome of DNA replication, in Saccharomyces cerevisiae. We describe the formation of pre-catenanes during replication and how inhibition of topoisomerase 2 leads to the accumulation of intertwined sister duplexes. This knowledge is essential to determine how replication forks blockage or pausing affects the dynamic of DNA topology during replication.
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Affiliation(s)
- Alicia Castán
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, Madrid, 28040, Spain
| | - Pablo Hernández
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, Madrid, 28040, Spain
| | - Dora B Krimer
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, Madrid, 28040, Spain
| | - Jorge B Schvartzman
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, Madrid, 28040, Spain.
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42
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Clarke DJ, Azuma Y. Non-Catalytic Roles of the Topoisomerase IIα C-Terminal Domain. Int J Mol Sci 2017; 18:ijms18112438. [PMID: 29149026 PMCID: PMC5713405 DOI: 10.3390/ijms18112438] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 11/10/2017] [Accepted: 11/14/2017] [Indexed: 12/26/2022] Open
Abstract
DNA Topoisomerase IIα (Topo IIα) is a ubiquitous enzyme in eukaryotes that performs the strand passage reaction where a double helix of DNA is passed through a second double helix. This unique reaction is critical for numerous cellular processes. However, the enzyme also possesses a C-terminal domain (CTD) that is largely dispensable for the strand passage reaction but is nevertheless important for the fidelity of cell division. Recent studies have expanded our understanding of the roles of the Topo IIα CTD, in particular in mitotic mechanisms where the CTD is modified by Small Ubiquitin-like Modifier (SUMO), which in turn provides binding sites for key regulators of mitosis.
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Affiliation(s)
- Duncan J Clarke
- Department of Genetics, Cell Biology & Development, University of Minnesota, 420 Washington Ave SE, Minneapolis, MN 55455, USA.
| | - Yoshiaki Azuma
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA.
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43
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Mariezcurrena A, Uhlmann F. Observation of DNA intertwining along authentic budding yeast chromosomes. Genes Dev 2017; 31:2151-2161. [PMID: 29208645 PMCID: PMC5749163 DOI: 10.1101/gad.305557.117] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Accepted: 10/30/2017] [Indexed: 11/24/2022]
Abstract
DNA replication of circular genomes generates physically interlinked or catenated sister DNAs. These are resolved through transient DNA fracture by type II topoisomerases to permit chromosome segregation during cell division. Topoisomerase II is similarly required for linear chromosome segregation, suggesting that linear chromosomes also remain intertwined following DNA replication. Indeed, chromosome resolution defects are a frequent cause of chromosome segregation failure and consequent aneuploidies. When and where intertwines arise and persist along linear chromosomes are not known, owing to the difficulty of demonstrating intertwining of linear DNAs. Here, we used excision of chromosomal regions as circular "loop outs" to convert sister chromatid intertwines into catenated circles. This revealed intertwining at replication termination and cohesin-binding sites, where intertwines are thought to arise and persist but not to a greater extent than elsewhere in the genome. Intertwining appears to spread evenly along chromosomes but is excluded from heterochromatin. We found that intertwines arise before replication termination, suggesting that replication forks rotate during replication elongation to dissipate torsion ahead of the forks. Our approach provides previously inaccessible insight into the topology of eukaryotic chromosomes and illuminates a process critical for successful chromosome segregation.
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Affiliation(s)
- Ainhoa Mariezcurrena
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
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44
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Khan FA, Ali SO. Physiological Roles of DNA Double-Strand Breaks. J Nucleic Acids 2017; 2017:6439169. [PMID: 29181194 PMCID: PMC5664317 DOI: 10.1155/2017/6439169] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Accepted: 09/24/2017] [Indexed: 12/20/2022] Open
Abstract
Genomic integrity is constantly threatened by sources of DNA damage, internal and external alike. Among the most cytotoxic lesions is the DNA double-strand break (DSB) which arises from the cleavage of both strands of the double helix. Cells boast a considerable set of defences to both prevent and repair these breaks and drugs which derail these processes represent an important category of anticancer therapeutics. And yet, bizarrely, cells deploy this very machinery for the intentional and calculated disruption of genomic integrity, harnessing potentially destructive DSBs in delicate genetic transactions. Under tight spatiotemporal regulation, DSBs serve as a tool for genetic modification, widely used across cellular biology to generate diverse functionalities, ranging from the fundamental upkeep of DNA replication, transcription, and the chromatin landscape to the diversification of immunity and the germline. Growing evidence points to a role of aberrant DSB physiology in human disease and an understanding of these processes may both inform the design of new therapeutic strategies and reduce off-target effects of existing drugs. Here, we review the wide-ranging roles of physiological DSBs and the emerging network of their multilateral regulation to consider how the cell is able to harness DNA breaks as a critical biochemical tool.
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Affiliation(s)
- Farhaan A. Khan
- School of Clinical Medicine, Addenbrooke's Hospital, University of Cambridge, Hills Road, Cambridge CB2 0SP, UK
| | - Syed O. Ali
- School of Clinical Medicine, Addenbrooke's Hospital, University of Cambridge, Hills Road, Cambridge CB2 0SP, UK
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45
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Genome-Scale Genetic Interactions and Cell Imaging Confirm Cytokinesis as Deleterious to Transient Topoisomerase II Deficiency in Saccharomyces cerevisiae. G3-GENES GENOMES GENETICS 2017; 7:3379-3391. [PMID: 28839115 PMCID: PMC5633387 DOI: 10.1534/g3.117.300104] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Topoisomerase II (Top2) is an essential protein that resolves DNA catenations. When Top2 is inactivated, mitotic catastrophe results from massive entanglement of chromosomes. Top2 is also the target of many first-line anticancer drugs, the so-called Top2 poisons. Often, tumors become resistant to these drugs by acquiring hypomorphic mutations in the genes encoding Top2 Here, we have compared the cell cycle and nuclear segregation of two coisogenic Saccharomyces cerevisiae strains carrying top2 thermosensitive alleles that differ in their resistance to Top2 poisons: the broadly-used poison-sensitive top2-4 and the poison-resistant top2-5 Furthermore, we have performed genome-scale synthetic genetic array (SGA) analyses for both alleles under permissive conditions, chronic sublethal Top2 downregulation, and acute, yet transient, Top2 inactivation. We find that slowing down mitotic progression, especially at the time of execution of the mitotic exit network (MEN), protects against Top2 deficiency. In all conditions, genetic protection was stronger in top2-5; this correlated with cell biology experiments in this mutant, whereby we observed destabilization of both chromatin and ultrafine anaphase bridges by execution of MEN and cytokinesis. Interestingly, whereas transient inactivation of the critical MEN driver Cdc15 partly suppressed top2-5 lethality, this was not the case when earlier steps within anaphase were disrupted; i.e., top2-5 cdc14-1 We discuss the basis of this difference and suggest that accelerated progression through mitosis may be a therapeutic strategy to hypersensitize cancer cells carrying hypomorphic mutations in TOP2.
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46
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Schalbetter SA, Goloborodko A, Fudenberg G, Belton JM, Miles C, Yu M, Dekker J, Mirny L, Baxter J. SMC complexes differentially compact mitotic chromosomes according to genomic context. Nat Cell Biol 2017; 19:1071-1080. [PMID: 28825700 PMCID: PMC5640152 DOI: 10.1038/ncb3594] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 07/19/2017] [Indexed: 12/26/2022]
Abstract
Structural maintenance of chromosomes (SMC) protein complexes are key determinants of chromosome conformation. Using Hi-C and polymer modelling, we study how cohesin and condensin, two deeply conserved SMC complexes, organize chromosomes in the budding yeast Saccharomyces cerevisiae. The canonical role of cohesin is to co-align sister chromatids, while condensin generally compacts mitotic chromosomes. We find strikingly different roles for the two complexes in budding yeast mitosis. First, cohesin is responsible for compacting mitotic chromosome arms, independently of sister chromatid cohesion. Polymer simulations demonstrate that this role can be fully accounted for through cis-looping of chromatin. Second, condensin is generally dispensable for compaction along chromosome arms. Instead, it plays a targeted role compacting the rDNA proximal regions and promoting resolution of peri-centromeric regions. Our results argue that the conserved mechanism of SMC complexes is to form chromatin loops and that distinct SMC-dependent looping activities are selectively deployed to appropriately compact chromosomes.
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MESH Headings
- Adenosine Triphosphatases/genetics
- Adenosine Triphosphatases/metabolism
- Cell Cycle Proteins/genetics
- Cell Cycle Proteins/metabolism
- Chromatin/chemistry
- Chromatin/genetics
- Chromatin/metabolism
- Chromatin Assembly and Disassembly
- Chromosomal Proteins, Non-Histone/genetics
- Chromosomal Proteins, Non-Histone/metabolism
- Chromosome Structures
- Chromosomes, Fungal/chemistry
- Chromosomes, Fungal/genetics
- Chromosomes, Fungal/metabolism
- Computer Simulation
- DNA, Fungal/chemistry
- DNA, Fungal/genetics
- DNA, Fungal/metabolism
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- DNA, Ribosomal/metabolism
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Mitosis
- Models, Genetic
- Models, Molecular
- Multiprotein Complexes/genetics
- Multiprotein Complexes/metabolism
- Nucleic Acid Conformation
- Saccharomyces cerevisiae/genetics
- Saccharomyces cerevisiae/growth & development
- Saccharomyces cerevisiae/metabolism
- Saccharomyces cerevisiae Proteins/genetics
- Saccharomyces cerevisiae Proteins/metabolism
- Structure-Activity Relationship
- Cohesins
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Affiliation(s)
| | - Anton Goloborodko
- Institute for Medical Engineering and Sciences, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Geoffrey Fudenberg
- Institute for Medical Engineering and Sciences, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Jon-Matthew Belton
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
| | - Catrina Miles
- Genome Damage and Stability Centre, Science Park Road, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Miao Yu
- Genome Damage and Stability Centre, Science Park Road, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Job Dekker
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
| | - Leonid Mirny
- Institute for Medical Engineering and Sciences, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Jonathan Baxter
- Genome Damage and Stability Centre, Science Park Road, University of Sussex, Falmer, Brighton BN1 9RQ, UK
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47
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Puddu F, Salguero I, Herzog M, Geisler NJ, Costanzo V, Jackson SP. Chromatin determinants impart camptothecin sensitivity. EMBO Rep 2017; 18:1000-1012. [PMID: 28389464 PMCID: PMC5452016 DOI: 10.15252/embr.201643560] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 03/07/2017] [Accepted: 03/09/2017] [Indexed: 11/09/2022] Open
Abstract
Camptothecin-induced locking of topoisomerase 1 on DNA generates a physical barrier to replication fork progression and creates topological stress. By allowing replisome rotation, absence of the Tof1/Csm3 complex promotes the conversion of impending topological stress to DNA catenation and causes camptothecin hypersensitivity. Through synthetic viability screening, we discovered that histone H4 K16 deacetylation drives the sensitivity of yeast cells to camptothecin and that inactivation of this pathway by mutating H4 K16 or the genes SIR1-4 suppresses much of the hypersensitivity of tof1∆ strains towards this agent. We show that disruption of rDNA or telomeric silencing does not mediate camptothecin resistance but that disruption of Sir1-dependent chromatin domains is sufficient to suppress camptothecin sensitivity in wild-type and tof1∆ cells. We suggest that topoisomerase 1 inhibition in proximity of these domains causes topological stress that leads to DNA hypercatenation, especially in the absence of the Tof1/Csm3 complex. Finally, we provide evidence of the evolutionarily conservation of this mechanism.
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Affiliation(s)
- Fabio Puddu
- The Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Israel Salguero
- The Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Mareike Herzog
- The Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
- The Wellcome Trust Sanger Institute, Hinxton Cambridge, UK
| | - Nicola J Geisler
- The Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Vincenzo Costanzo
- IFOM (Fondazione Istituto FIRC di Oncologia Molecolare), Milan, Italy
| | - Stephen P Jackson
- The Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
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48
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Abstract
Genome duplication is carried out by pairs of replication forks that assemble at origins of replication and then move in opposite directions. DNA replication ends when converging replication forks meet. During this process, which is known as replication termination, DNA synthesis is completed, the replication machinery is disassembled and daughter molecules are resolved. In this Review, we outline the steps that are likely to be common to replication termination in most organisms, namely, fork convergence, synthesis completion, replisome disassembly and decatenation. We briefly review the mechanism of termination in the bacterium Escherichia coli and in simian virus 40 (SV40) and also focus on recent advances in eukaryotic replication termination. In particular, we discuss the recently discovered E3 ubiquitin ligases that control replisome disassembly in yeast and higher eukaryotes, and how their activity is regulated to avoid genome instability.
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49
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Abstract
The accurate and complete replication of genomic DNA is essential for all life. In eukaryotic cells, the assembly of the multi-enzyme replisomes that perform replication is divided into stages that occur at distinct phases of the cell cycle. Replicative DNA helicases are loaded around origins of DNA replication exclusively during G1 phase. The loaded helicases are then activated during S phase and associate with the replicative DNA polymerases and other accessory proteins. The function of the resulting replisomes is monitored by checkpoint proteins that protect arrested replisomes and inhibit new initiation when replication is inhibited. The replisome also coordinates nucleosome disassembly, assembly, and the establishment of sister chromatid cohesion. Finally, when two replisomes converge they are disassembled. Studies in Saccharomyces cerevisiae have led the way in our understanding of these processes. Here, we review our increasingly molecular understanding of these events and their regulation.
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50
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Jain CK, Majumder HK, Roychoudhury S. Natural Compounds as Anticancer Agents Targeting DNA Topoisomerases. Curr Genomics 2017; 18:75-92. [PMID: 28503091 PMCID: PMC5321768 DOI: 10.2174/1389202917666160808125213] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 11/23/2015] [Accepted: 11/26/2015] [Indexed: 12/14/2022] Open
Abstract
DNA topoisomerases are important cellular enzymes found in almost all types of living cells (eukaryotic and prokaryotic). These enzymes are essential for various DNA metabolic processes e.g. replication, transcription, recombination, chromosomal decatenation etc. These enzymes are important molecular drug targets and inhibitors of these enzymes are widely used as effective anticancer and antibacterial drugs. However, topoisomerase inhibitors have some therapeutic limitations and they exert serious side effects during cancer chemotherapy. Thus, development of novel anticancer topoisomerase inhibitors is necessary for improving cancer chemotherapy. Nature serves as a repertoire of structurally and chemically diverse molecules and in the recent years many DNA topoisomerase inhibitors have been identified from natural sources. The present review discusses anticancer properties and therapeutic importance of eighteen recently identified natural topoisomerase inhibitors (from the year 2009 to 2015). Structural characteristics of these novel inhibitors provide backbones for designing and developing new anticancer drugs.
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Affiliation(s)
- Chetan Kumar Jain
- Infectious Diseases and Immunology Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Kolkata-700032, India
| | - Hemanta Kumar Majumder
- Infectious Diseases and Immunology Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Kolkata-700032, India
| | - Susanta Roychoudhury
- Division of Research, Saroj Gupta Cancer Centre & Research Institute, M G Road, Thakurpukur, Kolkata-700 063, India
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