1
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Shaw AE, Whitted JE, Mihelich MN, Reitman HJ, Timmerman AJ, Schauer GD. Revised Mechanism of Hydroxyurea Induced Cell Cycle Arrest and an Improved Alternative. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.02.583010. [PMID: 38496404 PMCID: PMC10942336 DOI: 10.1101/2024.03.02.583010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Replication stress describes various types of endogenous and exogenous challenges to DNA replication in S-phase. Stress during this critical process results in helicase-polymerase decoupling at replication forks, triggering the S-phase checkpoint, which orchestrates global replication fork stalling and delayed entry into G2. The replication stressor most often used to induce the checkpoint response is hydroxyurea (HU), a chemotherapeutic agent. The primary mechanism of S-phase checkpoint activation by HU has thus far been considered to be a reduction of dNTP synthesis by inhibition of ribonucleotide reductase (RNR), leading to helicase-polymerase decoupling and subsequent activation of the checkpoint, mediated by the replisome associated effector kinase Mrc1. In contrast, we observe that HU causes cell cycle arrest in budding yeast independent of both the Mrc1-mediated replication checkpoint response and the Psk1-Mrc1 oxidative signaling pathway. We demonstrate a direct relationship between HU incubation and reactive oxygen species (ROS) production in yeast nuclei. We further observe that ROS strongly inhibits the in vitro polymerase activity of replicative polymerases (Pols), Pol α, Pol δ, and Pol ε, causing polymerase complex dissociation and subsequent loss of DNA substrate binding, likely through oxidation of their integral iron sulfur Fe-S clusters. Finally, we present "RNR-deg," a genetically engineered alternative to HU in yeast with greatly increased specificity of RNR inhibition, allowing researchers to achieve fast, nontoxic, and more readily reversible checkpoint activation compared to HU, avoiding harmful ROS generation and associated downstream cellular effects that may confound interpretation of results.
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Affiliation(s)
- Alisa E Shaw
- Department of Biochemistry and Molecular Biology, Colorado State University, CO, USA
| | - Jackson E Whitted
- Department of Biochemistry and Molecular Biology, Colorado State University, CO, USA
| | - Mattias N Mihelich
- Department of Biochemistry and Molecular Biology, Colorado State University, CO, USA
| | - Hannah J Reitman
- Department of Biochemistry and Molecular Biology, Colorado State University, CO, USA
| | - Adam J Timmerman
- Department of Biochemistry and Molecular Biology, Colorado State University, CO, USA
| | - Grant D Schauer
- Department of Biochemistry and Molecular Biology, Colorado State University, CO, USA
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2
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Bocanegra R, Ortíz-Rodríguez M, Zumeta L, Plaza-G A I, Faro E, Ibarra B. DNA replication machineries: Structural insights from crystallography and electron microscopy. Enzymes 2023; 54:249-271. [PMID: 37945174 DOI: 10.1016/bs.enz.2023.07.004] [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: 11/12/2023]
Abstract
Since the discovery of DNA as the genetic material, scientists have been investigating how the information contained in this biological polymer is transmitted from generation to generation. X-ray crystallography, and more recently, cryo-electron microscopy techniques have been instrumental in providing essential information about the structure, functions and interactions of the DNA and the protein machinery (replisome) responsible for its replication. In this chapter, we highlight several works that describe the structure and structure-function relationships of the core components of the prokaryotic and eukaryotic replisomes. We also discuss the most recent studies on the structural organization of full replisomes.
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Affiliation(s)
| | | | - Lyra Zumeta
- IMDEA Nanociencia, Campus Cantoblanco, Madrid, Spain
| | | | - Elías Faro
- IMDEA Nanociencia, Campus Cantoblanco, Madrid, Spain
| | - Borja Ibarra
- IMDEA Nanociencia, Campus Cantoblanco, Madrid, Spain.
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3
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Hadjicharalambous A, Whale AJ, Can G, Skehel JM, Houseley JM, Zegerman P. Checkpoint kinase interaction with DNA polymerase alpha regulates replication progression during stress. Wellcome Open Res 2023; 8:327. [PMID: 37766847 PMCID: PMC10521137 DOI: 10.12688/wellcomeopenres.19617.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/06/2023] [Indexed: 09/29/2023] Open
Abstract
Background: In eukaryotes, replication stress activates a checkpoint response, which facilitates genome duplication by stabilising the replisome. How the checkpoint kinases regulate the replisome remains poorly understood. The aim of this study is to identify new targets of checkpoint kinases within the replisome during replication stress. Methods: Here we use an unbiased biotin proximity-ligation approach in Saccharomyces cerevisiae to identify new interactors and substrates of the checkpoint kinase Rad53 in vivo. Results: From this screen, we identified the replication initiation factor Sld7 as a Rad53 substrate, and Pol1, the catalytic subunit of polymerase a, as a Rad53-interactor. We showed that CDK phosphorylation of Pol1 mediates its interaction with Rad53. Combined with other interactions between Rad53 and the replisome, this Rad53-Pol1 interaction is important for viability and replisome progression during replication stress. Conclusions: Together, we explain how the interactions of Rad53 with the replisome are controlled by both replication stress and the cell cycle, and why these interactions might be important for coordinating the stabilisation of both the leading and lagging strand machineries.
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Affiliation(s)
| | - Alex J. Whale
- Epigenetics Programme, Babraham Institute, University of Cambridge, Cambridge, England, CB22 3AT, UK
| | - Geylani Can
- Department of Biochemistry, University of Cambridge, Cambridge, England, CB2 1GA, UK
| | - J. Mark Skehel
- Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, London, England, CB2 0QH, UK
| | - Jonathan M. Houseley
- Epigenetics Programme, Babraham Institute, University of Cambridge, Cambridge, England, CB22 3AT, UK
| | - Philip Zegerman
- Department of Biochemistry, University of Cambridge, Cambridge, England, CB2 1GA, UK
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4
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Patel JA, Kim H. The TIMELESS effort for timely DNA replication and protection. Cell Mol Life Sci 2023; 80:84. [PMID: 36892674 PMCID: PMC9998586 DOI: 10.1007/s00018-023-04738-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 02/16/2023] [Accepted: 02/24/2023] [Indexed: 03/10/2023]
Abstract
Accurate replication of the genome is fundamental to cellular survival and tumor prevention. The DNA replication fork is vulnerable to DNA lesions and damages that impair replisome progression, and improper control over DNA replication stress inevitably causes fork stalling and collapse, a major source of genome instability that fuels tumorigenesis. The integrity of the DNA replication fork is maintained by the fork protection complex (FPC), in which TIMELESS (TIM) constitutes a key scaffold that couples the CMG helicase and replicative polymerase activities, in conjunction with its interaction with other proteins associated with the replication machinery. Loss of TIM or the FPC in general results in impaired fork progression, elevated fork stalling and breakage, and a defect in replication checkpoint activation, thus underscoring its pivotal role in protecting the integrity of both active and stalled replication forks. TIM is upregulated in multiple cancers, which may represent a replication vulnerability of cancer cells that could be exploited for new therapies. Here, we discuss recent advances on our understanding of the multifaceted roles of TIM in DNA replication and stalled fork protection, and how its complex functions are engaged in collaboration with other genome surveillance and maintenance factors.
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Affiliation(s)
- Jinal A Patel
- Department of Pharmacological Sciences, State University of New York at Stony Brook, Basic Sciences Tower 8-125, 101 Nicolls Rd, Stony Brook, NY, 11794, USA
| | - Hyungjin Kim
- Department of Pharmacological Sciences, State University of New York at Stony Brook, Basic Sciences Tower 8-125, 101 Nicolls Rd, Stony Brook, NY, 11794, USA.
- Stony Brook Cancer Center and Renaissance School of Medicine, Stony Brook University, Basic Sciences Tower 8-125, 101 Nicolls Rd, Stony Brook, NY, 11794, USA.
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5
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Li X, Wang L, Liu X, Zheng Z, Kong D. Cellular regulation and stability of DNA replication forks in eukaryotic cells. DNA Repair (Amst) 2022; 120:103418. [DOI: 10.1016/j.dnarep.2022.103418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 10/03/2022] [Accepted: 10/07/2022] [Indexed: 11/03/2022]
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6
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He R, Zhang Z. Rad53 arrests leading and lagging strand DNA synthesis via distinct mechanisms in response to DNA replication stress. Bioessays 2022; 44:e2200061. [PMID: 35778827 DOI: 10.1002/bies.202200061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 06/19/2022] [Accepted: 06/22/2022] [Indexed: 12/18/2022]
Abstract
DNA replication stress threatens ordinary DNA synthesis. The evolutionarily conserved DNA replication stress response pathway involves sensor kinase Mec1/ATR, adaptor protein Mrc1/Claspin, and effector kinase Rad53/Chk1, which spurs a host of changes to stabilize replication forks and maintain genome integrity. DNA replication forks consist of largely distinct sets of proteins at leading and lagging strands that function autonomously in DNA synthesis in vitro. In this article, we discuss eSPAN and BrdU-IP-ssSeq, strand-specific sequencing technologies that permit analysis of protein localization and DNA synthesis at individual strands in budding yeast. Using these approaches, we show that under replication stress Rad53 stalls DNA synthesis on both leading and lagging strands. On lagging strands, it stimulates PCNA unloading, and on leading strands, it attenuates the replication function of Mrc1-Tof1. We propose that in doing so, Rad53 couples leading and lagging strand DNA synthesis during replication stress, thereby preventing the emergence of harmful ssDNA.
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Affiliation(s)
- Richard He
- Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, New York, USA.,Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, New York, USA.,Department of Pediatrics, Columbia University Medical Center, New York, New York, USA.,Department of Genetics and Development, Columbia University Medical Center, New York, New York, USA
| | - Zhiguo Zhang
- Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, New York, USA.,Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, New York, USA.,Department of Pediatrics, Columbia University Medical Center, New York, New York, USA.,Department of Genetics and Development, Columbia University Medical Center, New York, New York, USA
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7
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Batté A, van der Horst SC, Tittel-Elmer M, Sun SM, Sharma S, van Leeuwen J, Chabes A, van Attikum H. Chl1 helicase controls replication fork progression by regulating dNTP pools. Life Sci Alliance 2022; 5:5/4/e202101153. [PMID: 35017203 PMCID: PMC8761496 DOI: 10.26508/lsa.202101153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 12/23/2021] [Accepted: 12/28/2021] [Indexed: 12/27/2022] Open
Abstract
Chl1 helicase affects RPA-dependent checkpoint activation after replication fork arrest by ensuring proper dNTP levels, thereby controlling replication fork progression under stress conditions. Eukaryotic cells have evolved a replication stress response that helps to overcome stalled/collapsed replication forks and ensure proper DNA replication. The replication checkpoint protein Mrc1 plays important roles in these processes, although its functional interactions are not fully understood. Here, we show that MRC1 negatively interacts with CHL1, which encodes the helicase protein Chl1, suggesting distinct roles for these factors during the replication stress response. Indeed, whereas Mrc1 is known to facilitate the restart of stalled replication forks, we uncovered that Chl1 controls replication fork rate under replication stress conditions. Chl1 loss leads to increased RNR1 gene expression and dNTP levels at the onset of S phase likely without activating the DNA damage response. This in turn impairs the formation of RPA-coated ssDNA and subsequent checkpoint activation. Thus, the Chl1 helicase affects RPA-dependent checkpoint activation in response to replication fork arrest by ensuring proper intracellular dNTP levels, thereby controlling replication fork progression under replication stress conditions.
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Affiliation(s)
- Amandine Batté
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | | | - Mireille Tittel-Elmer
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands.,Electrical Engineering, Mathematics and Computer Science, Delft University of Technology, Delft, Netherlands
| | - Su Ming Sun
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Sushma Sharma
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Jolanda van Leeuwen
- Center for Integrative Genomics, Université de Lausanne, Lausanne-Dorigny, Switzerland
| | - Andrei Chabes
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Haico van Attikum
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
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8
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Grabarczyk DB. The Fork Protection Complex: A Regulatory Hub at the Head of the Replisome. Subcell Biochem 2022; 99:83-107. [PMID: 36151374 DOI: 10.1007/978-3-031-00793-4_3] [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: 06/16/2023]
Abstract
As well as accurately duplicating DNA, the eukaryotic replisome performs a variety of other crucial tasks to maintain genomic stability. For example, organizational elements, like cohesin, must be transferred from the front of the fork to the new strands, and when there is replication stress, forks need to be protected and checkpoint signalling activated. The Tof1-Csm3 (or Timeless-Tipin in humans) Fork Protection Complex (FPC) ensures efficient replisome progression and is required for a range of replication-associated activities. Recent studies have begun to reveal the structure of this complex, and how it functions within the replisome to perform its diverse roles. The core of the FPC acts as a DNA grip on the front of the replisome to regulate fork progression. Other flexibly linked domains and motifs mediate interactions with proteins and specific DNA structures, enabling the FPC to act as a hub at the head of the replication fork.
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Affiliation(s)
- Daniel B Grabarczyk
- Rudolf Virchow Center for Integrative and Translational Bioimaging, Institute for Structural Biology, University of Würzburg, Würzburg, Germany.
- Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria.
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9
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Jones ML, Baris Y, Taylor MRG, Yeeles JTP. Structure of a human replisome shows the organisation and interactions of a DNA replication machine. EMBO J 2021; 40:e108819. [PMID: 34694004 PMCID: PMC8634136 DOI: 10.15252/embj.2021108819] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 09/28/2021] [Accepted: 09/30/2021] [Indexed: 02/01/2023] Open
Abstract
The human replisome is an elaborate arrangement of molecular machines responsible for accurate chromosome replication. At its heart is the CDC45-MCM-GINS (CMG) helicase, which, in addition to unwinding the parental DNA duplex, arranges many proteins including the leading-strand polymerase Pol ε, together with TIMELESS-TIPIN, CLASPIN and AND-1 that have key and varied roles in maintaining smooth replisome progression. How these proteins are coordinated in the human replisome is poorly understood. We have determined a 3.2 Å cryo-EM structure of a human replisome comprising CMG, Pol ε, TIMELESS-TIPIN, CLASPIN and AND-1 bound to replication fork DNA. The structure permits a detailed understanding of how AND-1, TIMELESS-TIPIN and Pol ε engage CMG, reveals how CLASPIN binds to multiple replisome components and identifies the position of the Pol ε catalytic domain. Furthermore, the intricate network of contacts contributed by MCM subunits and TIMELESS-TIPIN with replication fork DNA suggests a mechanism for strand separation.
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10
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Aricthota S, Haldar D. DDK/Hsk1 phosphorylates and targets fission yeast histone deacetylase Hst4 for degradation to stabilize stalled DNA replication forks. eLife 2021; 10:70787. [PMID: 34608864 PMCID: PMC8565929 DOI: 10.7554/elife.70787] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 10/01/2021] [Indexed: 01/01/2023] Open
Abstract
In eukaryotes, paused replication forks are prone to collapse, which leads to genomic instability, a hallmark of cancer. Dbf4-dependent kinase (DDK)/Hsk1Cdc7 is a conserved replication initiator kinase with conflicting roles in replication stress response. Here, we show that fission yeast DDK/Hsk1 phosphorylates sirtuin, Hst4 upon replication stress at C-terminal serine residues. Phosphorylation of Hst4 by DDK marks it for degradation via the ubiquitin ligase SCFpof3. Phosphorylation-defective hst4 mutant (4SA-hst4) displays defective recovery from replication stress, faulty fork restart, slow S-phase progression and decreased viability. The highly conserved fork protection complex (FPC) stabilizes stalled replication forks. We found that the recruitment of FPC components, Swi1 and Mcl1 to the chromatin is compromised in the 4SA-hst4 mutant, although whole cell levels increased. These defects are dependent upon H3K56ac and independent of intra S-phase checkpoint activation. Finally, we show conservation of H3K56ac-dependent regulation of Timeless, Tipin, and And-1 in human cells. We propose that degradation of Hst4 via DDK increases H3K56ac, changing the chromatin state in the vicinity of stalled forks facilitating recruitment and function of FPC. Overall, this study identified a crucial role of DDK and FPC in the regulation of replication stress response with implications in cancer therapeutics.
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Affiliation(s)
- Shalini Aricthota
- Laboratory of Chromatin Biology and Epigenetics, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, India.,Graduate Studies, Manipal Academy of Higher Education, Manipal, India
| | - Devyani Haldar
- Laboratory of Chromatin Biology and Epigenetics, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, India
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11
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A mechanism for Rad53 to couple leading- and lagging-strand DNA synthesis under replication stress in budding yeast. Proc Natl Acad Sci U S A 2021; 118:2109334118. [PMID: 34531325 DOI: 10.1073/pnas.2109334118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/09/2021] [Indexed: 12/18/2022] Open
Abstract
In response to DNA replication stress, DNA replication checkpoint kinase Mec1 phosphorylates Mrc1, which in turn activates Rad53 to prevent the generation of deleterious single-stranded DNA, a process that remains poorly understood. We previously reported that lagging-strand DNA synthesis proceeds farther than leading strand in rad53-1 mutant cells defective in replication checkpoint under replication stress, resulting in the exposure of long stretches of the leading-strand templates. Here, we show that asymmetric DNA synthesis is also observed in mec1-100 and mrc1-AQ cells defective in replication checkpoint but, surprisingly, not in mrc1∆ cells in which both DNA replication and checkpoint functions of Mrc1 are missing. Furthermore, depletion of either Mrc1 or its partner, Tof1, suppresses the asymmetric DNA synthesis in rad53-1 mutant cells. Thus, the DNA replication checkpoint pathway couples leading- and lagging-strand DNA synthesis by attenuating the replication function of Mrc1-Tof1 under replication stress.
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12
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McClure AW, Diffley JF. Rad53 checkpoint kinase regulation of DNA replication fork rate via Mrc1 phosphorylation. eLife 2021; 10:69726. [PMID: 34387546 PMCID: PMC8387023 DOI: 10.7554/elife.69726] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Accepted: 08/12/2021] [Indexed: 12/18/2022] Open
Abstract
The Rad53 DNA checkpoint protein kinase plays multiple roles in the budding yeast cell response to DNA replication stress. Key amongst these is its enigmatic role in safeguarding DNA replication forks. Using DNA replication reactions reconstituted with purified proteins, we show Rad53 phosphorylation of Sld3/7 or Dbf4-dependent kinase blocks replication initiation whilst phosphorylation of Mrc1 or Mcm10 slows elongation. Mrc1 phosphorylation is necessary and sufficient to slow replication forks in complete reactions; Mcm10 phosphorylation can also slow replication forks, but only in the absence of unphosphorylated Mrc1. Mrc1 stimulates the unwinding rate of the replicative helicase, CMG, and Rad53 phosphorylation of Mrc1 prevents this. We show that a phosphorylation-mimicking Mrc1 mutant cannot stimulate replication in vitro and partially rescues the sensitivity of a rad53 null mutant to genotoxic stress in vivo. Our results show that Rad53 protects replication forks in part by antagonising Mrc1 stimulation of CMG unwinding.
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Affiliation(s)
- Allison W McClure
- Chromosome Replication Laboratory, The Francis Crick Institute, London, United Kingdom
| | - John Fx Diffley
- Chromosome Replication Laboratory, The Francis Crick Institute, London, United Kingdom
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13
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Guilliam TA. Mechanisms for Maintaining Eukaryotic Replisome Progression in the Presence of DNA Damage. Front Mol Biosci 2021; 8:712971. [PMID: 34295925 PMCID: PMC8290200 DOI: 10.3389/fmolb.2021.712971] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 06/25/2021] [Indexed: 12/04/2022] Open
Abstract
The eukaryotic replisome coordinates template unwinding and nascent-strand synthesis to drive DNA replication fork progression and complete efficient genome duplication. During its advancement along the parental template, each replisome may encounter an array of obstacles including damaged and structured DNA that impede its progression and threaten genome stability. A number of mechanisms exist to permit replisomes to overcome such obstacles, maintain their progression, and prevent fork collapse. A combination of recent advances in structural, biochemical, and single-molecule approaches have illuminated the architecture of the replisome during unperturbed replication, rationalised the impact of impediments to fork progression, and enhanced our understanding of DNA damage tolerance mechanisms and their regulation. This review focusses on these studies to provide an updated overview of the mechanisms that support replisomes to maintain their progression on an imperfect template.
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Affiliation(s)
- Thomas A. Guilliam
- Division of Protein and Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom
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14
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Shimada K, Tsai-Pflugfelder M, Vijeh Motlagh ND, Delgoshaie N, Fuchs J, Gut H, Gasser SM. The stabilized Pol31-Pol3 interface counteracts Pol32 ablation with differential effects on repair. Life Sci Alliance 2021; 4:4/9/e202101138. [PMID: 34226278 PMCID: PMC8321694 DOI: 10.26508/lsa.202101138] [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: 06/17/2021] [Revised: 06/23/2021] [Accepted: 06/24/2021] [Indexed: 11/24/2022] Open
Abstract
DNA polymerase δ, which contains the catalytic subunit, Pol3, Pol31, and Pol32, contributes both to DNA replication and repair. The deletion of pol31 is lethal, and compromising the Pol3-Pol31 interaction domains confers hypersensitivity to cold, hydroxyurea (HU), and methyl methanesulfonate, phenocopying pol32Δ. We have identified alanine-substitutions in pol31 that suppress these deficiencies in pol32Δ cells. We characterize two mutants, pol31-T415A and pol31-W417A, which map to a solvent-exposed loop that mediates Pol31-Pol3 and Pol31-Rev3 interactions. The pol31-T415A substitution compromises binding to the Pol3 CysB domain, whereas Pol31-W417A improves it. Importantly, loss of Pol32, such as pol31-T415A, leads to reduced Pol3 and Pol31 protein levels, which are restored by pol31-W417A. The mutations have differential effects on recovery from acute HU, break-induced replication and trans-lesion synthesis repair pathways. Unlike trans-lesion synthesis and growth on HU, the loss of break-induced replication in pol32Δ cells is not restored by pol31-W417A, highlighting pathway-specific roles for Pol32 in fork-related repair. Intriguingly, CHIP analyses of replication forks on HU showed that pol32Δ and pol31-T415A indirectly destabilize DNA pol α and pol ε at stalled forks.
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Affiliation(s)
- Kenji Shimada
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | | | | | - Neda Delgoshaie
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Jeannette Fuchs
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Heinz Gut
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Susan M Gasser
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
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15
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Liu Y, Wang L, Xu X, Yuan Y, Zhang B, Li Z, Xie Y, Yan R, Zheng Z, Ji J, Murray JM, Carr AM, Kong D. The intra-S phase checkpoint directly regulates replication elongation to preserve the integrity of stalled replisomes. Proc Natl Acad Sci U S A 2021; 118:e2019183118. [PMID: 34108240 PMCID: PMC8214678 DOI: 10.1073/pnas.2019183118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
DNA replication is dramatically slowed down under replication stress. The regulation of replication speed is a conserved response in eukaryotes and, in fission yeast, requires the checkpoint kinases Rad3ATR and Cds1Chk2 However, the underlying mechanism of this checkpoint regulation remains unresolved. Here, we report that the Rad3ATR-Cds1Chk2 checkpoint directly targets the Cdc45-MCM-GINS (CMG) replicative helicase under replication stress. When replication forks stall, the Cds1Chk2 kinase directly phosphorylates Cdc45 on the S275, S322, and S397 residues, which significantly reduces CMG helicase activity. Furthermore, in cds1Chk2 -mutated cells, the CMG helicase and DNA polymerases are physically separated, potentially disrupting replisomes and collapsing replication forks. This study demonstrates that the intra-S phase checkpoint directly regulates replication elongation, reduces CMG helicase processivity, prevents CMG helicase delinking from DNA polymerases, and therefore helps preserve the integrity of stalled replisomes and replication forks.
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Affiliation(s)
- Yang Liu
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
- National Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Lu Wang
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
- National Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Xin Xu
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
- National Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Yue Yuan
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
- National Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Bo Zhang
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
- National Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Zeyang Li
- National Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Yuchen Xie
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
- National Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Rui Yan
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
- National Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Zeqi Zheng
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
- National Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Jianguo Ji
- National Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Johanne M Murray
- Genome Damage and Stability Center, School of Life Sciences, University of Sussex, Brighton BN1 9RQ, United Kingdom
| | - Antony M Carr
- Genome Damage and Stability Center, School of Life Sciences, University of Sussex, Brighton BN1 9RQ, United Kingdom
| | - Daochun Kong
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China;
- National Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
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16
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Shyian M, Shore D. Approaching Protein Barriers: Emerging Mechanisms of Replication Pausing in Eukaryotes. Front Cell Dev Biol 2021; 9:672510. [PMID: 34124054 PMCID: PMC8194067 DOI: 10.3389/fcell.2021.672510] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 05/03/2021] [Indexed: 11/13/2022] Open
Abstract
During nuclear DNA replication multiprotein replisome machines have to jointly traverse and duplicate the total length of each chromosome during each cell cycle. At certain genomic locations replisomes encounter tight DNA-protein complexes and slow down. This fork pausing is an active process involving recognition of a protein barrier by the approaching replisome via an evolutionarily conserved Fork Pausing/Protection Complex (FPC). Action of the FPC protects forks from collapse at both programmed and accidental protein barriers, thus promoting genome integrity. In addition, FPC stimulates the DNA replication checkpoint and regulates topological transitions near the replication fork. Eukaryotic cells have been proposed to employ physiological programmed fork pausing for various purposes, such as maintaining copy number at repetitive loci, precluding replication-transcription encounters, regulating kinetochore assembly, or controlling gene conversion events during mating-type switching. Here we review the growing number of approaches used to study replication pausing in vivo and in vitro as well as the characterization of additional factors recently reported to modulate fork pausing in different systems. Specifically, we focus on the positive role of topoisomerases in fork pausing. We describe a model where replisome progression is inherently cautious, which ensures general preservation of fork stability and genome integrity but can also carry out specialized functions at certain loci. Furthermore, we highlight classical and novel outstanding questions in the field and propose venues for addressing them. Given how little is known about replisome pausing at protein barriers in human cells more studies are required to address how conserved these mechanisms are.
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Affiliation(s)
- Maksym Shyian
- Department of Molecular Biology, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - David Shore
- Department of Molecular Biology, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva, Switzerland
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17
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Abstract
The faithful and timely copying of DNA by molecular machines known as replisomes depends on a disparate suite of enzymes and scaffolding factors working together in a highly orchestrated manner. Large, dynamic protein-nucleic acid assemblies that selectively morph between distinct conformations and compositional states underpin this critical cellular process. In this article, we discuss recent progress outlining the physical basis of replisome construction and progression in eukaryotes.
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Affiliation(s)
- Ilan Attali
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA;
| | - Michael R Botchan
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720, USA
| | - James M Berger
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA;
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18
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Xing P, Dong Y, Zhao J, Zhou Z, Li Z, Wang Y, Li M, Zhang X, Chen X. Mrc1-Dependent Chromatin Compaction Represses DNA Double-Stranded Break Repair by Homologous Recombination Upon Replication Stress. Front Cell Dev Biol 2021; 9:630777. [PMID: 33681209 PMCID: PMC7928320 DOI: 10.3389/fcell.2021.630777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 01/06/2021] [Indexed: 11/13/2022] Open
Abstract
The coordination of DNA replication and repair is critical for the maintenance of genome stability. It has been shown that the Mrc1-mediated S phase checkpoint inhibits DNA double-stranded break (DSB) repair through homologous recombination (HR). How the replication checkpoint inhibits HR remains only partially understood. Here we show that replication stress induces the suppression of both Sgs1/Dna2- and Exo1-mediated resection pathways in an Mrc1-dependent manner. As a result, the loading of the single-stranded DNA binding factor replication protein A (RPA) and Rad51 and DSB repair by HR were severely impaired under replication stress. Notably, the deletion of MRC1 partially restored the recruitment of resection enzymes, DSB end resection, and the loading of RPA and Rad51. The role of Mrc1 in inhibiting DSB end resection is independent of Csm3, Tof1, or Ctf4. Mechanistically, we reveal that replication stress induces global chromatin compaction in a manner partially dependent on Mrc1, and this chromatin compaction limits the access of chromatin remodeling factors and HR proteins, leading to the suppression of HR. Our study reveals a critical role of the Mrc1-dependent chromatin structure change in coordinating DNA replication and recombination under replication stress.
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Affiliation(s)
- Poyuan Xing
- Hubei Key Laboratory of Cell Homeostasis and the Institute for Advanced Studies, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yang Dong
- Hubei Key Laboratory of Cell Homeostasis and the Institute for Advanced Studies, College of Life Sciences, Wuhan University, Wuhan, China
| | - Jingyu Zhao
- Hubei Key Laboratory of Cell Homeostasis and the Institute for Advanced Studies, College of Life Sciences, Wuhan University, Wuhan, China
| | - Zhou Zhou
- Hubei Key Laboratory of Cell Homeostasis and the Institute for Advanced Studies, College of Life Sciences, Wuhan University, Wuhan, China
| | - Zhao Li
- Hubei Key Laboratory of Cell Homeostasis and the Institute for Advanced Studies, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yu Wang
- Hubei Key Laboratory of Cell Homeostasis and the Institute for Advanced Studies, College of Life Sciences, Wuhan University, Wuhan, China
| | - Mengfei Li
- Hubei Key Laboratory of Cell Homeostasis and the Institute for Advanced Studies, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xinghua Zhang
- Hubei Key Laboratory of Cell Homeostasis and the Institute for Advanced Studies, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xuefeng Chen
- Hubei Key Laboratory of Cell Homeostasis and the Institute for Advanced Studies, College of Life Sciences, Wuhan University, Wuhan, China
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19
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Westhorpe R, Keszthelyi A, Minchell NE, Jones D, Baxter J. Separable functions of Tof1/Timeless in intra-S-checkpoint signalling, replisome stability and DNA topological stress. Nucleic Acids Res 2020; 48:12169-12187. [PMID: 33166393 PMCID: PMC7708041 DOI: 10.1093/nar/gkaa963] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 10/06/2020] [Accepted: 10/09/2020] [Indexed: 12/16/2022] Open
Abstract
The highly conserved Tof1/Timeless proteins minimise replication stress and promote normal DNA replication. They are required to mediate the DNA replication checkpoint (DRC), the stable pausing of forks at protein fork blocks, the coupling of DNA helicase and polymerase functions during replication stress (RS) and the preferential resolution of DNA topological stress ahead of the fork. Here we demonstrate that the roles of the Saccharomyces cerevisiae Timeless protein Tof1 in DRC signalling and resolution of DNA topological stress require distinct N and C terminal regions of the protein, whereas the other functions of Tof1 are closely linked to the stable interaction between Tof1 and its constitutive binding partner Csm3/Tipin. By separating the role of Tof1 in DRC from fork stabilisation and coupling, we show that Tof1 has distinct activities in checkpoint activation and replisome stability to ensure the viable completion of DNA replication following replication stress.
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Affiliation(s)
- Rose Westhorpe
- 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
| | - Nicola E Minchell
- Genome Damage and Stability Centre, School of Life Sciences, Science Park Road, University of Sussex, Falmer, Brighton, East Sussex BN1 9RQ, UK
| | - David Jones
- 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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20
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Stokes K, Winczura A, Song B, Piccoli GD, Grabarczyk DB. Ctf18-RFC and DNA Pol ϵ form a stable leading strand polymerase/clamp loader complex required for normal and perturbed DNA replication. Nucleic Acids Res 2020; 48:8128-8145. [PMID: 32585006 PMCID: PMC7641331 DOI: 10.1093/nar/gkaa541] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 06/05/2020] [Accepted: 06/16/2020] [Indexed: 12/28/2022] Open
Abstract
The eukaryotic replisome must faithfully replicate DNA and cope with replication fork blocks and stalling, while simultaneously promoting sister chromatid cohesion. Ctf18-RFC is an alternative PCNA loader that links all these processes together by an unknown mechanism. Here, we use integrative structural biology combined with yeast genetics and biochemistry to highlight the specific functions that Ctf18-RFC plays within the leading strand machinery via an interaction with the catalytic domain of DNA Pol ϵ. We show that a large and unusually flexible interface enables this interaction to occur constitutively throughout the cell cycle and regardless of whether forks are replicating or stalled. We reveal that, by being anchored to the leading strand polymerase, Ctf18-RFC can rapidly signal fork stalling to activate the S phase checkpoint. Moreover, we demonstrate that, independently of checkpoint signaling or chromosome cohesion, Ctf18-RFC functions in parallel to Chl1 and Mrc1 to protect replication forks and cell viability.
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Affiliation(s)
- Katy Stokes
- University of Warwick, Warwick Medical School, Coventry, UK
| | | | - Boyuan Song
- Rudolf Virchow Center for Integrative and Translational Bioimaging, Institute for Structural Biology, University of Würzburg, Josef-Schneider-Str. 2, Würzburg 97080, Germany.,Department of Biochemistry, Biocenter, University of Würzburg, Am Hubland, Würzburg 97074, Germany
| | | | - Daniel B Grabarczyk
- Rudolf Virchow Center for Integrative and Translational Bioimaging, Institute for Structural Biology, University of Würzburg, Josef-Schneider-Str. 2, Würzburg 97080, Germany
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21
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Lerner LK, Holzer S, Kilkenny ML, Šviković S, Murat P, Schiavone D, Eldridge CB, Bittleston A, Maman JD, Branzei D, Stott K, Pellegrini L, Sale JE. Timeless couples G-quadruplex detection with processing by DDX11 helicase during DNA replication. EMBO J 2020; 39:e104185. [PMID: 32705708 PMCID: PMC7506991 DOI: 10.15252/embj.2019104185] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 06/25/2020] [Accepted: 06/26/2020] [Indexed: 12/27/2022] Open
Abstract
Regions of the genome with the potential to form secondary DNA structures pose a frequent and significant impediment to DNA replication and must be actively managed in order to preserve genetic and epigenetic integrity. How the replisome detects and responds to secondary structures is poorly understood. Here, we show that a core component of the fork protection complex in the eukaryotic replisome, Timeless, harbours in its C-terminal region a previously unappreciated DNA-binding domain that exhibits specific binding to G-quadruplex (G4) DNA structures. We show that this domain contributes to maintaining processive replication through G4-forming sequences, and exhibits partial redundancy with an adjacent PARP-binding domain. Further, this function of Timeless requires interaction with and activity of the helicase DDX11. Loss of both Timeless and DDX11 causes epigenetic instability at G4-forming sequences and DNA damage. Our findings indicate that Timeless contributes to the ability of the replisome to sense replication-hindering G4 formation and ensures the prompt resolution of these structures by DDX11 to maintain processive DNA synthesis.
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Affiliation(s)
- Leticia K Lerner
- MRC Laboratory of Molecular BiologyCambridgeUK
- Present address:
Centre de Recherche des CordeliersCell Death and Drug Resistance in Hematological Disorders TeamINSERM UMRS 1138Sorbonne UniversitéParisFrance
| | - Sandro Holzer
- Department of BiochemistryUniversity of CambridgeCambridgeUK
| | | | | | | | | | | | | | - Joseph D Maman
- Department of BiochemistryUniversity of CambridgeCambridgeUK
| | - Dana Branzei
- IFOMFondazione Italiana per la Ricerca sul CancroInstitute of Molecular OncologyMilanItaly
| | - Katherine Stott
- Department of BiochemistryUniversity of CambridgeCambridgeUK
| | - Luca Pellegrini
- Department of BiochemistryUniversity of CambridgeCambridgeUK
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22
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Guilliam TA, Yeeles JTP. An updated perspective on the polymerase division of labor during eukaryotic DNA replication. Crit Rev Biochem Mol Biol 2020; 55:469-481. [PMID: 32883112 DOI: 10.1080/10409238.2020.1811630] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In eukaryotes three DNA polymerases (Pols), α, δ, and ε, are tasked with bulk DNA synthesis of nascent strands during genome duplication. Most evidence supports a model where Pol α initiates DNA synthesis before Pol ε and Pol δ replicate the leading and lagging strands, respectively. However, a number of recent reports, enabled by advances in biochemical and genetic techniques, have highlighted emerging roles for Pol δ in all stages of leading-strand synthesis; initiation, elongation, and termination, as well as fork restart. By focusing on these studies, this review provides an updated perspective on the division of labor between the replicative polymerases during DNA replication.
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Affiliation(s)
- Thomas A Guilliam
- Division of Protein and Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Joseph T P Yeeles
- Division of Protein and Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
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23
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Deegan TD, Mukherjee PP, Fujisawa R, Polo Rivera C, Labib K. CMG helicase disassembly is controlled by replication fork DNA, replisome components and a ubiquitin threshold. eLife 2020; 9:e60371. [PMID: 32804080 PMCID: PMC7462611 DOI: 10.7554/elife.60371] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 08/14/2020] [Indexed: 12/20/2022] Open
Abstract
The eukaryotic replisome assembles around the CMG helicase, which stably associates with DNA replication forks throughout elongation. When replication terminates, CMG is ubiquitylated on its Mcm7 subunit and disassembled by the Cdc48/p97 ATPase. Until now, the regulation that restricts CMG ubiquitylation to termination was unknown, as was the mechanism of disassembly. By reconstituting these processes with purified budding yeast proteins, we show that ubiquitylation is tightly repressed throughout elongation by the Y-shaped DNA structure of replication forks. Termination removes the repressive DNA structure, whereupon long K48-linked ubiquitin chains are conjugated to CMG-Mcm7, dependent on multiple replisome components that bind to the ubiquitin ligase SCFDia2. This mechanism pushes CMG beyond a '5-ubiquitin threshold' that is inherent to Cdc48, which specifically unfolds ubiquitylated Mcm7 and thereby disassembles CMG. These findings explain the exquisite regulation of CMG disassembly and provide a general model for the disassembly of ubiquitylated protein complexes by Cdc48.
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Affiliation(s)
- Tom D Deegan
- The MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of DundeeDundeeUnited Kingdom
| | - Progya P Mukherjee
- The MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of DundeeDundeeUnited Kingdom
| | - Ryo Fujisawa
- The MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of DundeeDundeeUnited Kingdom
| | - Cristian Polo Rivera
- The MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of DundeeDundeeUnited Kingdom
| | - Karim Labib
- The MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of DundeeDundeeUnited Kingdom
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24
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Baretić D, Jenkyn-Bedford M, Aria V, Cannone G, Skehel M, Yeeles JTP. Cryo-EM Structure of the Fork Protection Complex Bound to CMG at a Replication Fork. Mol Cell 2020; 78:926-940.e13. [PMID: 32369734 PMCID: PMC7276988 DOI: 10.1016/j.molcel.2020.04.012] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 04/09/2020] [Accepted: 04/09/2020] [Indexed: 12/15/2022]
Abstract
The eukaryotic replisome, organized around the Cdc45-MCM-GINS (CMG) helicase, orchestrates chromosome replication. Multiple factors associate directly with CMG, including Ctf4 and the heterotrimeric fork protection complex (Csm3/Tof1 and Mrc1), which has important roles including aiding normal replication rates and stabilizing stalled forks. How these proteins interface with CMG to execute these functions is poorly understood. Here we present 3 to 3.5 Å resolution electron cryomicroscopy (cryo-EM) structures comprising CMG, Ctf4, and the fork protection complex at a replication fork. The structures provide high-resolution views of CMG-DNA interactions, revealing a mechanism for strand separation, and show Csm3/Tof1 “grip” duplex DNA ahead of CMG via a network of interactions important for efficient replication fork pausing. Although Mrc1 was not resolved in our structures, we determine its topology in the replisome by cross-linking mass spectrometry. Collectively, our work reveals how four highly conserved replisome components collaborate with CMG to facilitate replisome progression and maintain genome stability. Cryo-EM structure of Csm3/Tof1 and Ctf4 bound to the eukaryotic CMG helicase Csm3/Tof1 are positioned at the front of the replisome where they grip duplex DNA High-resolution views of CMG-DNA contacts suggest a mechanism for strand separation Mrc1 binds across one side of CMG contacting the front and back of the replisome
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Affiliation(s)
- Domagoj Baretić
- Laboratory of Molecular Biology, Medical Research Council, Cambridge CB2 0QH, UK
| | | | - Valentina Aria
- Laboratory of Molecular Biology, Medical Research Council, Cambridge CB2 0QH, UK
| | - Giuseppe Cannone
- Laboratory of Molecular Biology, Medical Research Council, Cambridge CB2 0QH, UK
| | - Mark Skehel
- Laboratory of Molecular Biology, Medical Research Council, Cambridge CB2 0QH, UK
| | - Joseph T P Yeeles
- Laboratory of Molecular Biology, Medical Research Council, Cambridge CB2 0QH, UK.
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25
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Feu S, Unzueta F, Llopis A, Semple JI, Ercilla A, Guaita-Esteruelas S, Jaumot M, Freire R, Agell N. OZF is a Claspin-interacting protein essential to maintain the replication fork progression rate under replication stress. FASEB J 2020; 34:6907-6919. [PMID: 32267586 DOI: 10.1096/fj.201901926r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 03/10/2020] [Accepted: 03/16/2020] [Indexed: 12/12/2022]
Abstract
DNA replication is essential for cell proliferation and is one of the cell cycle stages where DNA is more vulnerable. Replication stress is a prominent property of tumor cells and an emerging target for cancer therapy. Although it is not directly involved in nucleotide incorporation, Claspin is a protein with relevant functions in DNA replication. It harbors a DNA-binding domain that interacts preferentially with branched or forked DNA molecules. It also acts as a platform for the interaction of proteins related to DNA damage checkpoint activation, DNA repair, DNA replication origin firing, and fork progression. In order to find new proteins potentially involved in the regulation of DNA replication, we performed a two-hybrid screen to discover new Claspin-binding proteins. This system allowed us to identify the zinc-finger protein OZF (ZNF146) as a new Claspin-interacting protein. OZF is also present at replication forks and co-immunoprecipitates not only with Claspin but also with other replisome components. Interestingly, OZF depletion does not affect DNA replication in a normal cell cycle, but its depletion induces a reduction in the fork progression rate under replication stress conditions. Our results suggest that OZF is a Claspin-binding protein with a specific function in fork progression under replication stress.
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Affiliation(s)
- Sonia Feu
- Departament de Biomedicina, Facultat de Medicina i Ciències de la Salut, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Barcelona, Spain
| | - Fernando Unzueta
- Departament de Biomedicina, Facultat de Medicina i Ciències de la Salut, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Barcelona, Spain
| | - Alba Llopis
- Departament de Biomedicina, Facultat de Medicina i Ciències de la Salut, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Barcelona, Spain
| | | | - Amaia Ercilla
- Departament de Biomedicina, Facultat de Medicina i Ciències de la Salut, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Barcelona, Spain
| | - Sandra Guaita-Esteruelas
- Departament de Biomedicina, Facultat de Medicina i Ciències de la Salut, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Barcelona, Spain
| | - Montserrat Jaumot
- Departament de Biomedicina, Facultat de Medicina i Ciències de la Salut, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Barcelona, Spain
| | - Raimundo Freire
- Unidad de Investigación, Hospital Universitario de Canarias, FIISC, La Laguna, Spain.,Instituto de Tecnologías Biomédicas, Universidad de La Laguna, La Laguna, Spain.,Facultad de Ciencias de la Salud, Universidad Fernando Pessoa Canarias, Las Palmas de Gran Canaria, Spain
| | - Neus Agell
- Departament de Biomedicina, Facultat de Medicina i Ciències de la Salut, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Barcelona, Spain
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26
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Functional interplay between the oxidative stress response and DNA damage checkpoint signaling for genome maintenance in aerobic organisms. J Microbiol 2019; 58:81-91. [DOI: 10.1007/s12275-020-9520-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 11/29/2019] [Accepted: 11/30/2019] [Indexed: 12/13/2022]
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27
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Ma M, Rodriguez A, Sugimoto K. Activation of ATR-related protein kinase upon DNA damage recognition. Curr Genet 2019; 66:327-333. [PMID: 31624858 DOI: 10.1007/s00294-019-01039-w] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/08/2019] [Accepted: 10/10/2019] [Indexed: 12/20/2022]
Abstract
Chromosomes are constantly damaged by exogenous and endogenous factors. To cope with DNA damage, eukaryotic cells are equipped with three phosphatidylinositol 3-kinase-related kinases (PIKKs), such as ATM, ATR, and DNA-PK. PIKKs are structurally related to phosphatidylinositol 3-kinase (lipid kinase), however possess protein kinase activities. The Mre11-Rad50-Nbs1 and the Ku complex interact with and activate ATM and DNA-PKcs at double-stranded DNA breaks (DSBs), respectively. In contrast, ATR responds to various types of DNA lesions by interacting with replication protein A (RPA)-covered single-stranded DNA (ssDNA). Several lines of evidence have established a model in which ATR is activated by interacting with ATR activating proteins including TopBP1 and ETAA1 at DNA lesions in humans, yet the interaction of ATR with RPA-covered ssDNA does not result in ATR activation. In budding yeast, the Mec1-Ddc2 complex (Mec1-Ddc2) corresponds to ATR-ATRIP. Similar to ATR, Mec1 activation is accomplished by interactions with Mec1 activating proteins, which are Ddc1, Dpb11 (TopBP1 homolog) and Dna2. However, recent studies provide results supporting the idea that Mec1ATR is also activated by interacting with RPA-covered ssDNA tracts. These observations suggest that all the ATM, ATR, DNA-PK family proteins can be activated immediately upon DNA damage recognition.
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Affiliation(s)
- Minh Ma
- Department of Microbiology, Biochemistry and Molecular Genetics, International Center for Public Health, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, USA
| | - Anibian Rodriguez
- Department of Microbiology, Biochemistry and Molecular Genetics, International Center for Public Health, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, USA
| | - Katsunori Sugimoto
- Department of Microbiology, Biochemistry and Molecular Genetics, International Center for Public Health, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, USA.
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28
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Abstract
Maintenance of genome integrity is a key process in all organisms. DNA polymerases (Pols) are central players in this process as they are in charge of the faithful reproduction of the genetic information, as well as of DNA repair. Interestingly, all eukaryotes possess a large repertoire of polymerases. Three protein complexes, DNA Pol α, δ, and ε, are in charge of nuclear DNA replication. These enzymes have the fidelity and processivity required to replicate long DNA sequences, but DNA lesions can block their progression. Consequently, eukaryotic genomes also encode a variable number of specialized polymerases (between five and 16 depending on the organism) that are involved in the replication of damaged DNA, DNA repair, and organellar DNA replication. This diversity of enzymes likely stems from their ability to bypass specific types of lesions. In the past 10–15 years, our knowledge regarding plant DNA polymerases dramatically increased. In this review, we discuss these recent findings and compare acquired knowledge in plants to data obtained in other eukaryotes. We also discuss the emerging links between genome and epigenome replication.
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29
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A tel2 Mutation That Destabilizes the Tel2-Tti1-Tti2 Complex Eliminates Rad3 ATR Kinase Signaling in the DNA Replication Checkpoint and Leads to Telomere Shortening in Fission Yeast. Mol Cell Biol 2019; 39:MCB.00175-19. [PMID: 31332096 DOI: 10.1128/mcb.00175-19] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 07/19/2019] [Indexed: 12/12/2022] Open
Abstract
In response to perturbed DNA replication, ATR (ataxia telangiectasia and Rad3-related) kinase is activated to initiate the checkpoint signaling necessary for maintaining genome integrity and cell survival. To better understand the signaling mechanism, we carried out a large-scale genetic screen in fission yeast looking for mutants with enhanced sensitivity to hydroxyurea. From a collection of ∼370 primary mutants, we found a few mutants in which Rad3 (ATR ortholog)-mediated phospho-signaling was significantly compromised. One such mutant carried an uncharacterized mutation in tel2, a gene encoding an essential and highly conserved eukaryotic protein. Previous studies in various biological models have shown that Tel2 mainly functions in Tel2-Tti1-Tti2 (TTT) complex that regulates the steady-state levels of all phosphatidylinositol 3-kinase-like protein kinases, including ATR. We show here that although the levels of Rad3 and Rad3-mediated phospho-signaling in DNA damage checkpoint were moderately reduced in the tel2 mutant, the phospho-signaling in the DNA replication checkpoint was almost completely eliminated. In addition, the tel2 mutation caused telomere shortening. Since the interactions of Tel2 with Tti1 and Tti2 were significantly weakened by the mutation, destabilization of the TTT complex likely contributes to the observed checkpoint and telomere defects.
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30
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Gellon L, Kaushal S, Cebrián J, Lahiri M, Mirkin SM, Freudenreich CH. Mrc1 and Tof1 prevent fragility and instability at long CAG repeats by their fork stabilizing function. Nucleic Acids Res 2019; 47:794-805. [PMID: 30476303 PMCID: PMC6344861 DOI: 10.1093/nar/gky1195] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 11/13/2018] [Indexed: 12/14/2022] Open
Abstract
Fork stabilization at DNA impediments is key to maintaining replication fork integrity and preventing chromosome breaks. Mrc1 and Tof1 are two known stabilizers that travel with the replication fork. In addition to a structural role, Mrc1 has a DNA damage checkpoint function. Using a yeast model system, we analyzed the role of Mrc1 and Tof1 at expanded CAG repeats of medium and long lengths, which are known to stall replication forks and cause trinucleotide expansion diseases such as Huntington's disease and myotonic dystrophy. We demonstrate that the fork stabilizer but not the checkpoint activation function of Mrc1 is key for preventing DNA breakage and death of cells containing expanded CAG tracts. In contrast, both Mrc1 functions are important in preventing repeat length instability. Mrc1 has a general fork protector role that is evident at forks traversing both repetitive and non-repetitive DNA, though it becomes crucial at long CAG repeat lengths. In contrast, the role of Tof1 in preventing fork breakage is specific to long CAG tracts of 85 or more repeats. Our results indicate that long CAG repeats have a particular need for Tof1 and highlight the importance of fork stabilizers in maintaining fork integrity during replication of structure-forming repeats.
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Affiliation(s)
- Lionel Gellon
- Department of Biology, Tufts University, Suite 4700, 200 Boston Ave, Medford, MA 02155, USA
| | - Simran Kaushal
- Department of Biology, Tufts University, Suite 4700, 200 Boston Ave, Medford, MA 02155, USA
| | - Jorge Cebrián
- Department of Biology, Tufts University, Suite 4700, 200 Boston Ave, Medford, MA 02155, USA
| | - Mayurika Lahiri
- Department of Biology, Tufts University, Suite 4700, 200 Boston Ave, Medford, MA 02155, USA
| | - Sergei M Mirkin
- Department of Biology, Tufts University, Suite 4700, 200 Boston Ave, Medford, MA 02155, USA
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31
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Biswas H, Goto G, Wang W, Sung P, Sugimoto K. Ddc2ATRIP promotes Mec1ATR activation at RPA-ssDNA tracts. PLoS Genet 2019; 15:e1008294. [PMID: 31369547 PMCID: PMC6692047 DOI: 10.1371/journal.pgen.1008294] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 08/13/2019] [Accepted: 07/07/2019] [Indexed: 11/19/2022] Open
Abstract
The DNA damage checkpoint response is controlled by the phosphatidylinositol 3-kinase-related kinases (PIKK), including ataxia telangiectasia-mutated (ATM) and ATM and Rad3-related (ATR). ATR forms a complex with its partner ATRIP. In budding yeast, ATR and ATRIP correspond to Mec1 and Ddc2, respectively. ATRIP/Ddc2 interacts with replication protein A-bound single-stranded DNA (RPA-ssDNA) and recruits ATR/Mec1 to sites of DNA damage. Mec1 is stimulated by the canonical activators including Ddc1, Dpb11 and Dna2. We have characterized the ddc2-S4 mutation and shown that Ddc2 not only recruits Mec1 to sites of DNA damage but also stimulates Mec1 kinase activity. However, the underlying mechanism of Ddc2-dependent Mec1 activation remains to be elucidated. Here we show that Ddc2 promotes Mec1 activation independently of Ddc1/Dpb11/Dna2 function in vivo and through ssDNA recognition in vitro. The ddc2-S4 mutation diminishes damage-induced phosphorylation of the checkpoint mediators, Rad9 and Mrc1. Rad9 controls checkpoint throughout the cell-cycle whereas Mrc1 is specifically required for the S-phase checkpoint. Notably, S-phase checkpoint signaling is more defective in ddc2-S4 mutants than in cells where the Mec1 activators (Ddc1/Dpb11 and Dna2) are dysfunctional. To understand a role of Ddc2 in Mec1 activation, we reconstituted an in vitro assay using purified Mec1-Ddc2 complex, RPA and ssDNA. Whereas ssDNA stimulates kinase activity of the Mec1-Ddc2 complex, RPA does not. However, RPA can promote ssDNA-dependent Mec1 activation. Neither ssDNA nor RPA-ssDNA efficiently stimulates the Mec1-Ddc2 complex containing Ddc2-S4 mutant. Together, our data support a model in which Ddc2 promotes Mec1 activation at RPA-ssDNA tracts.
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Affiliation(s)
- Himadri Biswas
- Department of Microbiology, Biochemistry and Molecular Genetics, International Center for Public Health, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey, United States of America
| | - Greicy Goto
- Department of Microbiology, Biochemistry and Molecular Genetics, International Center for Public Health, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey, United States of America
| | - Weibin Wang
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Patrick Sung
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, Connecticut, United States of America
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Katsunori Sugimoto
- Department of Microbiology, Biochemistry and Molecular Genetics, International Center for Public Health, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey, United States of America
- * E-mail:
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32
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Saatchi F, Kirchmaier AL. Tolerance of DNA Replication Stress Is Promoted by Fumarate Through Modulation of Histone Demethylation and Enhancement of Replicative Intermediate Processing in Saccharomyces cerevisiae. Genetics 2019; 212:631-654. [PMID: 31123043 PMCID: PMC6614904 DOI: 10.1534/genetics.119.302238] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Accepted: 05/07/2019] [Indexed: 12/28/2022] Open
Abstract
Fumarase is a well-characterized TCA cycle enzyme that catalyzes the reversible conversion of fumarate to malate. In mammals, fumarase acts as a tumor suppressor, and loss-of-function mutations in the FH gene in hereditary leiomyomatosis and renal cell cancer result in the accumulation of intracellular fumarate-an inhibitor of α-ketoglutarate-dependent dioxygenases. Fumarase promotes DNA repair by nonhomologous end joining in mammalian cells through interaction with the histone variant H2A.Z, and inhibition of KDM2B, a H3 K36-specific histone demethylase. Here, we report that Saccharomyces cerevisiae fumarase, Fum1p, acts as a response factor during DNA replication stress, and fumarate enhances survival of yeast lacking Htz1p (H2A.Z in mammals). We observed that exposure to DNA replication stress led to upregulation as well as nuclear enrichment of Fum1p, and raising levels of fumarate in cells via deletion of FUM1 or addition of exogenous fumarate suppressed the sensitivity to DNA replication stress of htz1Δ mutants. This suppression was independent of modulating nucleotide pool levels. Rather, our results are consistent with fumarate conferring resistance to DNA replication stress in htz1Δ mutants by inhibiting the H3 K4-specific histone demethylase Jhd2p, and increasing H3 K4 methylation. Although the timing of checkpoint activation and deactivation remained largely unaffected by fumarate, sensors and mediators of the DNA replication checkpoint were required for fumarate-dependent resistance to replication stress in the htz1Δ mutants. Together, our findings imply metabolic enzymes and metabolites aid in processing replicative intermediates by affecting chromatin modification states, thereby promoting genome integrity.
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Affiliation(s)
- Faeze Saatchi
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907
- Purdue University Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907
- Bindley Bioscience Center, Purdue University, West Lafayette, Indiana 47907
| | - Ann L Kirchmaier
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907
- Purdue University Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907
- Bindley Bioscience Center, Purdue University, West Lafayette, Indiana 47907
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33
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DNA Replication Through Strand Displacement During Lagging Strand DNA Synthesis in Saccharomyces cerevisiae. Genes (Basel) 2019; 10:genes10020167. [PMID: 30795600 PMCID: PMC6409922 DOI: 10.3390/genes10020167] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 02/14/2019] [Accepted: 02/18/2019] [Indexed: 01/21/2023] Open
Abstract
This review discusses a set of experimental results that support the existence of extended strand displacement events during budding yeast lagging strand DNA synthesis. Starting from introducing the mechanisms and factors involved in leading and lagging strand DNA synthesis and some aspects of the architecture of the eukaryotic replisome, we discuss studies on bacterial, bacteriophage and viral DNA polymerases with potent strand displacement activities. We describe proposed pathways of Okazaki fragment processing via short and long flaps, with a focus on experimental results obtained in Saccharomyces cerevisiae that suggest the existence of frequent and extended strand displacement events during eukaryotic lagging strand DNA synthesis, and comment on their implications for genome integrity.
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34
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Azenha D, Lopes MC, Martins TC. Claspin: From replication stress and DNA damage responses to cancer therapy. DNA Repair (Amst) 2019; 115:203-246. [DOI: 10.1016/bs.apcsb.2018.10.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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35
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Helicase Subunit Cdc45 Targets the Checkpoint Kinase Rad53 to Both Replication Initiation and Elongation Complexes after Fork Stalling. Mol Cell 2018; 73:562-573.e3. [PMID: 30595439 PMCID: PMC6375734 DOI: 10.1016/j.molcel.2018.11.025] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 09/14/2018] [Accepted: 11/15/2018] [Indexed: 01/08/2023]
Abstract
Across eukaryotes, disruption of DNA replication causes an S phase checkpoint response, which regulates multiple processes, including inhibition of replication initiation and fork stabilization. How these events are coordinated remains poorly understood. Here, we show that the replicative helicase component Cdc45 targets the checkpoint kinase Rad53 to distinct replication complexes in the budding yeast Saccharomyces cerevisiae. Rad53 binds to forkhead-associated (FHA) interaction motifs in an unstructured loop region of Cdc45, which is phosphorylated by Rad53 itself, and this interaction is necessary for the inhibition of origin firing through Sld3. Cdc45 also recruits Rad53 to stalled replication forks, which we demonstrate is important for the response to replication stress. Finally, we show that a Cdc45 mutation found in patients with Meier-Gorlin syndrome disrupts the functional interaction with Rad53 in yeast. Together, we present a single mechanism by which a checkpoint kinase targets replication initiation and elongation complexes, which may be relevant to human disease. Cdc45 targets Rad53 to inhibit replication initiation through Sld3 Rad53 binds to the replisome in part through Cdc45 A Meier-Gorlin mutation in Cdc45 prevents interaction with Rad53
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36
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DDR Inc., one business, two associates. Curr Genet 2018; 65:445-451. [DOI: 10.1007/s00294-018-0908-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 11/18/2018] [Accepted: 11/19/2018] [Indexed: 01/03/2023]
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37
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Bacal J, Moriel-Carretero M, Pardo B, Barthe A, Sharma S, Chabes A, Lengronne A, Pasero P. Mrc1 and Rad9 cooperate to regulate initiation and elongation of DNA replication in response to DNA damage. EMBO J 2018; 37:e99319. [PMID: 30158111 PMCID: PMC6213276 DOI: 10.15252/embj.201899319] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 07/17/2018] [Accepted: 07/31/2018] [Indexed: 01/04/2023] Open
Abstract
The S-phase checkpoint maintains the integrity of the genome in response to DNA replication stress. In budding yeast, this pathway is initiated by Mec1 and is amplified through the activation of Rad53 by two checkpoint mediators: Mrc1 promotes Rad53 activation at stalled forks, and Rad9 is a general mediator of the DNA damage response. Here, we have investigated the interplay between Mrc1 and Rad9 in response to DNA damage and found that they control DNA replication through two distinct but complementary mechanisms. Mrc1 rapidly activates Rad53 at stalled forks and represses late-firing origins but is unable to maintain this repression over time. Rad9 takes over Mrc1 to maintain a continuous checkpoint signaling. Importantly, the Rad9-mediated activation of Rad53 slows down fork progression, supporting the view that the S-phase checkpoint controls both the initiation and the elongation of DNA replication in response to DNA damage. Together, these data indicate that Mrc1 and Rad9 play distinct functions that are important to ensure an optimal completion of S phase under replication stress conditions.
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Affiliation(s)
- Julien Bacal
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
| | - María Moriel-Carretero
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
| | - Benjamin Pardo
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
| | - Antoine Barthe
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
| | - Sushma Sharma
- Department of Medical Biochemistry and Biophysics and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Andrei Chabes
- Department of Medical Biochemistry and Biophysics and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Armelle Lengronne
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
| | - Philippe Pasero
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
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38
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Villa-Hernández S, Bermejo R. Replisome-Cohesin Interfacing: A Molecular Perspective. Bioessays 2018; 40:e1800109. [PMID: 30106480 DOI: 10.1002/bies.201800109] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 07/23/2018] [Indexed: 12/27/2022]
Abstract
Cohesion is established in S-phase through the action of key replisome factors as replication forks engage cohesin molecules. By holding sister chromatids together, cohesion critically assists both an equal segregation of the duplicated genetic material and an efficient repair of DNA breaks. Nonetheless, the molecular events leading the entrapment of nascent chromatids by cohesin during replication are only beginning to be understood. The authors describe here the essential structural features of the cohesin complex in connection to its ability to associate DNA molecules and review the current knowledge on the architectural-functional organization of the eukaryotic replisome, significantly advanced by recent biochemical and structural studies. In light of this novel insight, the authors discuss the mechanisms proposed to assist interfacing of replisomes with chromatin-bound cohesin complexes and elaborate on models for nascent chromatids entrapment by cohesin in the environment of the replication fork.
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Affiliation(s)
- Sara Villa-Hernández
- Centro de Investigaciones Biológicas (CIB-CSIC), Calle Ramiro de Maeztu 928040 Madrid, Spain
| | - Rodrigo Bermejo
- Centro de Investigaciones Biológicas (CIB-CSIC), Calle Ramiro de Maeztu 928040 Madrid, Spain
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39
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Srivatsan A, Li BZ, Szakal B, Branzei D, Putnam CD, Kolodner RD. The Swr1 chromatin-remodeling complex prevents genome instability induced by replication fork progression defects. Nat Commun 2018; 9:3680. [PMID: 30206225 PMCID: PMC6134005 DOI: 10.1038/s41467-018-06131-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 08/09/2018] [Indexed: 01/05/2023] Open
Abstract
Genome instability is associated with tumorigenesis. Here, we identify a role for the histone Htz1, which is deposited by the Swr1 chromatin-remodeling complex (SWR-C), in preventing genome instability in the absence of the replication fork/replication checkpoint proteins Mrc1, Csm3, or Tof1. When combined with deletion of SWR1 or HTZ1, deletion of MRC1, CSM3, or TOF1 or a replication-defective mrc1 mutation causes synergistic increases in gross chromosomal rearrangement (GCR) rates, accumulation of a broad spectrum of GCRs, and hypersensitivity to replication stress. The double mutants have severe replication defects and accumulate aberrant replication intermediates. None of the individual mutations cause large increases in GCR rates; however, defects in MRC1, CSM3 or TOF1 cause activation of the DNA damage checkpoint and replication defects. We propose a model in which Htz1 deposition and retention in chromatin prevents transiently stalled replication forks that occur in mrc1, tof1, or csm3 mutants from being converted to DNA double-strand breaks that trigger genome instability.
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Affiliation(s)
- Anjana Srivatsan
- Ludwig Institute for Cancer Research, University of California School of Medicine, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0669, USA
| | - Bin-Zhong Li
- Ludwig Institute for Cancer Research, University of California School of Medicine, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0669, USA
| | - Barnabas Szakal
- The FIRC Institute of Molecular Oncology Foundation, Via Adamello 16, 20139, Milan, Italy
| | - Dana Branzei
- The FIRC Institute of Molecular Oncology Foundation, Via Adamello 16, 20139, Milan, Italy.,Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche (IGM-CNR), Via Abbiategrasso 207, 27100, Pavia, Italy
| | - Christopher D Putnam
- Ludwig Institute for Cancer Research, University of California School of Medicine, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0669, USA.,Departments of Medicine, University of California School of Medicine, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0669, USA
| | - Richard D Kolodner
- Ludwig Institute for Cancer Research, University of California School of Medicine, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0669, USA. .,Cellular and Molecular Medicine, University of California School of Medicine, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0669, USA. .,Moores-UCSD Cancer Center, University of California School of Medicine, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0669, USA. .,Institute of Genomic Medicine, University of California School of Medicine, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0669, USA.
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40
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Bellelli R, Borel V, Logan C, Svendsen J, Cox DE, Nye E, Metcalfe K, O'Connell SM, Stamp G, Flynn HR, Snijders AP, Lassailly F, Jackson A, Boulton SJ. Polε Instability Drives Replication Stress, Abnormal Development, and Tumorigenesis. Mol Cell 2018; 70:707-721.e7. [PMID: 29754823 PMCID: PMC5972231 DOI: 10.1016/j.molcel.2018.04.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 03/28/2018] [Accepted: 04/03/2018] [Indexed: 01/08/2023]
Abstract
DNA polymerase ε (POLE) is a four-subunit complex and the major leading strand polymerase in eukaryotes. Budding yeast orthologs of POLE3 and POLE4 promote Polε processivity in vitro but are dispensable for viability in vivo. Here, we report that POLE4 deficiency in mice destabilizes the entire Polε complex, leading to embryonic lethality in inbred strains and extensive developmental abnormalities, leukopenia, and tumor predisposition in outbred strains. Comparable phenotypes of growth retardation and immunodeficiency are also observed in human patients harboring destabilizing mutations in POLE1. In both Pole4-/- mouse and POLE1 mutant human cells, Polε hypomorphy is associated with replication stress and p53 activation, which we attribute to inefficient replication origin firing. Strikingly, removing p53 is sufficient to rescue embryonic lethality and all developmental abnormalities in Pole4 null mice. However, Pole4-/-p53+/- mice exhibit accelerated tumorigenesis, revealing an important role for controlled CMG and origin activation in normal development and tumor prevention.
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Affiliation(s)
| | - Valerie Borel
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Clare Logan
- MRC Institute of Genetics & Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
| | | | - Danielle E Cox
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Emma Nye
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Kay Metcalfe
- Department of Genetic Medicine, St Mary's Hospital, Oxford Road, Manchester, M13 OJH, UK
| | - Susan M O'Connell
- Department of Paediatrics, Cork University Hospital, Wilton, Cork T12 DC4A, Ireland
| | - Gordon Stamp
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Helen R Flynn
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | | | | | - Andrew Jackson
- MRC Institute of Genetics & Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
| | - Simon J Boulton
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK.
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41
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Fang D, Lengronne A, Shi D, Forey R, Skrzypczak M, Ginalski K, Yan C, Wang X, Cao Q, Pasero P, Lou H. Dbf4 recruitment by forkhead transcription factors defines an upstream rate-limiting step in determining origin firing timing. Genes Dev 2018; 31:2405-2415. [PMID: 29330352 PMCID: PMC5795786 DOI: 10.1101/gad.306571.117] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 11/30/2017] [Indexed: 12/26/2022]
Abstract
Fang et al. show that Dbf4 is enriched at early origins through its interaction with forkhead transcription factors Fkh1 and Fkh2. Dbf4 interacts directly with Sld3 and promotes the recruitment of downstream limiting factors. Initiation of eukaryotic chromosome replication follows a spatiotemporal program. The current model suggests that replication origins compete for a limited pool of initiation factors. However, it remains to be answered how these limiting factors are preferentially recruited to early origins. Here, we report that Dbf4 is enriched at early origins through its interaction with forkhead transcription factors Fkh1 and Fkh2. This interaction is mediated by the Dbf4 C terminus and was successfully reconstituted in vitro. An interaction-defective mutant, dbf4ΔC, phenocopies fkh alleles in terms of origin firing. Remarkably, genome-wide replication profiles reveal that the direct fusion of the DNA-binding domain (DBD) of Fkh1 to Dbf4 restores the Fkh-dependent origin firing but interferes specifically with the pericentromeric origin activation. Furthermore, Dbf4 interacts directly with Sld3 and promotes the recruitment of downstream limiting factors. These data suggest that Fkh1 targets Dbf4 to a subset of noncentromeric origins to promote early replication in a manner that is reminiscent of the recruitment of Dbf4 to pericentromeric origins by Ctf19.
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Affiliation(s)
- Dingqiang Fang
- State Key Laboratory of Agro-Biotechnology, Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Armelle Lengronne
- Institute of Human Genetics, Centre National de la Recherche Scientifique, University of Montpellier, Equipe Labellisée Ligue Contre le Cancer, F-34396 Montpellier Cedex 5, France
| | - Di Shi
- State Key Laboratory of Agro-Biotechnology, Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Romain Forey
- Institute of Human Genetics, Centre National de la Recherche Scientifique, University of Montpellier, Equipe Labellisée Ligue Contre le Cancer, F-34396 Montpellier Cedex 5, France
| | - Magdalena Skrzypczak
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, 02-089 Warsaw, Poland
| | - Krzysztof Ginalski
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, 02-089 Warsaw, Poland
| | - Changhui Yan
- Department of Computer Science, North Dakota State University, Fargo, North Dakota 58108, USA
| | - Xiaoke Wang
- State Key Laboratory of Agro-Biotechnology, Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Qinhong Cao
- State Key Laboratory of Agro-Biotechnology, Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Philippe Pasero
- Institute of Human Genetics, Centre National de la Recherche Scientifique, University of Montpellier, Equipe Labellisée Ligue Contre le Cancer, F-34396 Montpellier Cedex 5, France
| | - Huiqiang Lou
- State Key Laboratory of Agro-Biotechnology, Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Biological Sciences, China Agricultural University, Beijing 100193, China
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42
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Zhang ZX, Zhang J, Cao Q, Campbell JL, Lou H. The DNA Pol ϵ stimulatory activity of Mrc1 is modulated by phosphorylation. Cell Cycle 2017; 17:64-72. [PMID: 29157061 DOI: 10.1080/15384101.2017.1403680] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
DNA replication checkpoint (Mec1-Mrc1-Rad53 in budding yeast) is an evolutionarily conserved surveillance system to ensure proper DNA replication and genome stability in all eukaryotes. Compared to its well-known function as a mediator of replication checkpoint, the exact role of Mrc1 as a component of normal replication forks remains relatively unclear. In this study, we provide in vitro biochemical evidence to support that yeast Mrc1 is able to enhance the activity of DNA polymerase ϵ (Pol ϵ), the major leading strand replicase. Mrc1 can selectively bind avidly to primer/template DNA bearing a single-stranded region, but not to double-stranded DNA (dsDNA). Mutations of the lysine residues within basic patch 1 (BP1) compromise both DNA binding and polymerase stimulatory activities. Interestingly, Mrc1-3D, a mutant mimicking phosphorylation by the Hog1/MAPK kinase during the osmotic stress response, retains DNA binding but not polymerase stimulation. The stimulatory effect is also abrogated in Mrc1 purified from cells treated with hydroxyurea (HU), which elicits replication checkpoint activation. Taken together with previous findings, these results imply that under unperturbed condition, Mrc1 has a DNA synthesis stimulatory activity, which can be eliminated via Mrc1 phosphorylation in response to replication and/or osmotic stresses.
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Affiliation(s)
- Zhong-Xin Zhang
- a Beijing Advanced Innovation Center for Food Nutrition and Human Health , State Key Laboratory of Agrobiotechnology , MOA Key Laboratory of Soil Microbiology , College of Biological Sciences , China Agricultural University , Beijing 100193 , China
| | - Jingjing Zhang
- a Beijing Advanced Innovation Center for Food Nutrition and Human Health , State Key Laboratory of Agrobiotechnology , MOA Key Laboratory of Soil Microbiology , College of Biological Sciences , China Agricultural University , Beijing 100193 , China
| | - Qinhong Cao
- a Beijing Advanced Innovation Center for Food Nutrition and Human Health , State Key Laboratory of Agrobiotechnology , MOA Key Laboratory of Soil Microbiology , College of Biological Sciences , China Agricultural University , Beijing 100193 , China
| | - Judith L Campbell
- b Braun Laboratories , California Institute of Technology , Pasadena , CA 91125 , USA
| | - Huiqiang Lou
- a Beijing Advanced Innovation Center for Food Nutrition and Human Health , State Key Laboratory of Agrobiotechnology , MOA Key Laboratory of Soil Microbiology , College of Biological Sciences , China Agricultural University , Beijing 100193 , China
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Coulton N, Caspari T. The kinase domain residue serine 173 of Schizosaccharomyces pombe Chk1 kinase is critical for the response to DNA replication stress. Biol Open 2017; 6:1840-1850. [PMID: 29092815 PMCID: PMC5769658 DOI: 10.1242/bio.029272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
While mammalian Chk1 kinase regulates replication origins, safeguards fork integrity and promotes fork progression, yeast Chk1 acts only in G1 and G2. We report here that the mutation of serine 173 (S173A) in the kinase domain of fission yeast Chk1 abolishes the G1-M and S-M checkpoints with little impact on the G2-M arrest. This separation-of-function mutation strongly reduces the Rad3-dependent phosphorylation of Chk1 at serine 345 during logarithmic growth, but not when cells experience exogenous DNA damage. Loss of S173 lowers the restrictive temperature of a catalytic DNA polymerase epsilon mutant (cdc20.M10) and is epistatic with a mutation in DNA polymerase delta (cdc6.23) when DNA is alkylated by methyl-methanesulfate (MMS). The chk1-S173A allele is uniquely sensitive to high MMS concentrations where it displays a partial checkpoint defect. A complete checkpoint defect occurs only when DNA replication forks break in cells without the intra-S phase checkpoint kinase Cds1. Chk1-S173A is also unable to block mitosis when the G1 transcription factor Cdc10 (cdc10.V50) is impaired. We conclude that serine 173, which is equivalent to lysine 166 in the activation loop of human Chk1, is only critical in DNA polymerase mutants or when forks collapse in the absence of Cds1. Summary: Mutation of serine-173 in the kinase domain of Chk1 increases genomic instability as it abolishes the response to DNA lesions that arise while chromosomes are being copied.
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Affiliation(s)
- Naomi Coulton
- Genome Biology Group, Bangor University, School of Medical Sciences, Bangor LL57 2UW, UK
| | - Thomas Caspari
- Genome Biology Group, Bangor University, School of Medical Sciences, Bangor LL57 2UW, UK .,Postgraduate School, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg, Austria
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Single-molecule visualization of Saccharomyces cerevisiae leading-strand synthesis reveals dynamic interaction between MTC and the replisome. Proc Natl Acad Sci U S A 2017; 114:10630-10635. [PMID: 28923950 DOI: 10.1073/pnas.1711291114] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The replisome, the multiprotein system responsible for genome duplication, is a highly dynamic complex displaying a large number of different enzyme activities. Recently, the Saccharomyces cerevisiae minimal replication reaction has been successfully reconstituted in vitro. This provided an opportunity to uncover the enzymatic activities of many of the components in a eukaryotic system. Their dynamic behavior and interactions in the context of the replisome, however, remain unclear. We use a tethered-bead assay to provide real-time visualization of leading-strand synthesis by the S. cerevisiae replisome at the single-molecule level. The minimal reconstituted leading-strand replisome requires 24 proteins, forming the CMG helicase, the Pol ε DNA polymerase, the RFC clamp loader, the PCNA sliding clamp, and the RPA single-stranded DNA binding protein. We observe rates and product lengths similar to those obtained from ensemble biochemical experiments. At the single-molecule level, we probe the behavior of two components of the replication progression complex and characterize their interaction with active leading-strand replisomes. The Minichromosome maintenance protein 10 (Mcm10), an important player in CMG activation, increases the number of productive replication events in our assay. Furthermore, we show that the fork protection complex Mrc1-Tof1-Csm3 (MTC) enhances the rate of the leading-strand replisome threefold. The introduction of periods of fast replication by MTC leads to an average rate enhancement of a factor of 2, similar to observations in cellular studies. We observe that the MTC complex acts in a dynamic fashion with the moving replisome, leading to alternating phases of slow and fast replication.
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45
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Azenha D, Lopes MC, Martins TC. Claspin functions in cell homeostasis-A link to cancer? DNA Repair (Amst) 2017; 59:27-33. [PMID: 28942358 DOI: 10.1016/j.dnarep.2017.09.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 09/06/2017] [Indexed: 10/18/2022]
Abstract
Cancer remains one of the leading causes of mortality worldwide. Most cancers present high degrees of genomic instability. DNA damage and replication checkpoints function as barriers to halt cell cycle progression until damage is resolved, preventing the perpetuation of errors. Activation of these checkpoints is critically dependent on Claspin, an adaptor protein that mediates the phosphorylation of the effector kinase Chk1 by ATR. However, Claspin also performs other roles related to the protection and maintenance of cell and genome integrity. For instance, following DNA damage and checkpoint activation, Claspin bridges checkpoint responses to DNA repair or to apoptosis. During DNA replication, Claspin acts a sensor and couples DNA unwinding to strand polymerization, and may also indirectly regulate replication initiation at firing origins. As Claspin participates in several processes that are vital to maintenance of cell homeostasis, its function is tightly regulated at multiple levels. Nevertheless, little is known about its role in cancer. Accumulating evidence suggests that Claspin inactivation could be an essential event during carcinogenesis, indicating that Claspin may function as a tumour suppressor. In this review, we will examine the functions of Claspin and how its deregulation may contribute to cancer initiation and progression. To conclude, we will discuss means by which Claspin can be targeted for cancer therapy.
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Affiliation(s)
- Diana Azenha
- Faculdade de Farmácia da Universidade de Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; Centro de Neurociências e Biologia Celular, Universidade de Coimbra, Rua Larga, Faculdade de Medicina, Pólo I, 1º andar, 3004-504 Coimbra, Portugal; Instituto Português de Oncologia de Coimbra de Francisco Gentil, Av. Bissaya Barreto 98, Apartado 2005, 3000-651, Coimbra, Portugal.
| | - Maria Celeste Lopes
- Faculdade de Farmácia da Universidade de Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; Centro de Neurociências e Biologia Celular, Universidade de Coimbra, Rua Larga, Faculdade de Medicina, Pólo I, 1º andar, 3004-504 Coimbra, Portugal.
| | - Teresa C Martins
- Centro de Neurociências e Biologia Celular, Universidade de Coimbra, Rua Larga, Faculdade de Medicina, Pólo I, 1º andar, 3004-504 Coimbra, Portugal; Instituto Português de Oncologia de Coimbra de Francisco Gentil, Av. Bissaya Barreto 98, Apartado 2005, 3000-651, Coimbra, Portugal.
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Zhang J, Shi D, Li X, Ding L, Tang J, Liu C, Shirahige K, Cao Q, Lou H. Rtt101-Mms1-Mms22 coordinates replication-coupled sister chromatid cohesion and nucleosome assembly. EMBO Rep 2017; 18:1294-1305. [PMID: 28615292 DOI: 10.15252/embr.201643807] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 05/03/2017] [Accepted: 05/08/2017] [Indexed: 01/10/2023] Open
Abstract
Two sister chromatids must be held together by a cohesion process from their synthesis during S phase to segregation in anaphase. Despite its pivotal role in accurate chromosome segregation, how cohesion is established remains elusive. Here, we demonstrate that yeast Rtt101-Mms1, Cul4 family E3 ubiquitin ligases are stronger dosage suppressors of loss-of-function eco1 mutants than PCNA The essential cohesion reaction, Eco1-catalyzed Smc3 acetylation is reduced in the absence of Rtt101-Mms1. One of the adaptor subunits, Mms22, associates directly with Eco1. Point mutations (L61D/G63D) in Eco1 that abolish the interaction with Mms22 impair Smc3 acetylation. Importantly, an eco1LGpol30A251V double mutant displays additive Smc3ac reduction. Moreover, Smc3 acetylation and cohesion defects also occur in the mutants of other replication-coupled nucleosome assembly (RCNA) factors upstream or downstream of Rtt101-Mms1, indicating unanticipated cross talk between histone modifications and cohesin acetylation. These data suggest that fork-associated Cul4-Ddb1 E3s, together with PCNA, coordinate chromatin reassembly and cohesion establishment on the newly replicated sister chromatids, which are crucial for maintaining genome and chromosome stability.
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Affiliation(s)
- Jingjing Zhang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Di Shi
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Xiaoli Li
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Lin Ding
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Jun Tang
- State Key Laboratory of Agrobiotechnology, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Cong Liu
- Laboratory of Genomic Stability, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Katsuhiko Shirahige
- Research Center for Epigenetic Disease, Institute of Molecular and Cellular Biosciences, The University of Tokyo, Tokyo, Japan
| | - Qinhong Cao
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Huiqiang Lou
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
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47
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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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Abstract
This review focuses on the biogenesis and composition of the eukaryotic DNA replication fork, with an emphasis on the enzymes that synthesize DNA and repair discontinuities on the lagging strand of the replication fork. Physical and genetic methodologies aimed at understanding these processes are discussed. The preponderance of evidence supports a model in which DNA polymerase ε (Pol ε) carries out the bulk of leading strand DNA synthesis at an undisturbed replication fork. DNA polymerases α and δ carry out the initiation of Okazaki fragment synthesis and its elongation and maturation, respectively. This review also discusses alternative proposals, including cellular processes during which alternative forks may be utilized, and new biochemical studies with purified proteins that are aimed at reconstituting leading and lagging strand DNA synthesis separately and as an integrated replication fork.
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Affiliation(s)
- Peter M J Burgers
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110;
| | - Thomas A Kunkel
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709;
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Pedroza-García JA, Mazubert C, Del Olmo I, Bourge M, Domenichini S, Bounon R, Tariq Z, Delannoy E, Piñeiro M, Jarillo JA, Bergounioux C, Benhamed M, Raynaud C. Function of the Plant DNA Polymerase Epsilon in Replicative Stress Sensing, a Genetic Analysis. PLANT PHYSIOLOGY 2017; 173:1735-1749. [PMID: 28153919 PMCID: PMC5338674 DOI: 10.1104/pp.17.00031] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 01/30/2017] [Indexed: 05/17/2023]
Abstract
Faithful transmission of the genetic information is essential in all living organisms. DNA replication is therefore a critical step of cell proliferation, because of the potential occurrence of replication errors or DNA damage when progression of a replication fork is hampered causing replicative stress. Like other types of DNA damage, replicative stress activates the DNA damage response, a signaling cascade allowing cell cycle arrest and repair of lesions. The replicative DNA polymerase ε (Pol ε) was shown to activate the S-phase checkpoint in yeast in response to replicative stress, but whether this mechanism functions in multicellular eukaryotes remains unclear. Here, we explored the genetic interaction between Pol ε and the main elements of the DNA damage response in Arabidopsis (Arabidopsis thaliana). We found that mutations affecting the polymerase domain of Pol ε trigger ATR-dependent signaling leading to SOG1 activation, WEE1-dependent cell cycle inhibition, and tolerance to replicative stress induced by hydroxyurea, but result in enhanced sensitivity to a wide range of DNA damaging agents. Using knock-down lines, we also provide evidence for the direct role of Pol ε in replicative stress sensing. Together, our results demonstrate that the role of Pol ε in replicative stress sensing is conserved in plants, and provide, to our knowledge, the first genetic dissection of the downstream signaling events in a multicellular eukaryote.
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Affiliation(s)
- José-Antonio Pedroza-García
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - Christelle Mazubert
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - Ivan Del Olmo
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - Mickael Bourge
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - Séverine Domenichini
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - Rémi Bounon
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - Zakia Tariq
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - Etienne Delannoy
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - Manuel Piñeiro
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - José A Jarillo
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - Catherine Bergounioux
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - Moussa Benhamed
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.)
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
| | - Cécile Raynaud
- Institute of Plant Sciences Paris-Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Évry, Université Paris-Saclay, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.);
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France (J.A.P.-G., C.M., S.D., R.B., Z.T., E.D., C.B., M.B., C.R.);
- Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM 28223-Pozuelo de Alarcón (Madrid), Spain (I.d.O., M.P., J.A.J.); and
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France (M.B.)
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S-phase checkpoint regulations that preserve replication and chromosome integrity upon dNTP depletion. Cell Mol Life Sci 2017; 74:2361-2380. [PMID: 28220209 PMCID: PMC5487892 DOI: 10.1007/s00018-017-2474-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 12/29/2016] [Accepted: 01/23/2017] [Indexed: 11/18/2022]
Abstract
DNA replication stress, an important source of genomic instability, arises upon different types of DNA replication perturbations, including those that stall replication fork progression. Inhibitors of the cellular pool of deoxynucleotide triphosphates (dNTPs) slow down DNA synthesis throughout the genome. Following depletion of dNTPs, the highly conserved replication checkpoint kinase pathway, also known as the S-phase checkpoint, preserves the functionality and structure of stalled DNA replication forks and prevents chromosome fragmentation. The underlying mechanisms involve pathways extrinsic to replication forks, such as those involving regulation of the ribonucleotide reductase activity, the temporal program of origin firing, and cell cycle transitions. In addition, the S-phase checkpoint modulates the function of replisome components to promote replication integrity. This review summarizes the various functions of the replication checkpoint in promoting replication fork stability and genome integrity in the face of replication stress caused by dNTP depletion.
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