1
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Shilkin ES, Petrova DV, Novikova AA, Boldinova EO, Zharkov DO, Makarova AV. Methylation and hydroxymethylation of cytosine alter activity and fidelity of translesion DNA polymerases. DNA Repair (Amst) 2024; 141:103712. [PMID: 38959714 DOI: 10.1016/j.dnarep.2024.103712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 05/24/2024] [Accepted: 06/11/2024] [Indexed: 07/05/2024]
Abstract
Epigenetic cytosine methylation covers most of genomic CpG dinucleotides in human cells. In addition to common deamination-mediated mutagenesis at CpG sites, an alternative deamination-independent pathway associated with DNA polymerase activity was previously described. This mutagenesis is characterized by the TCG→TTG mutational signature and is believed to arise from dAMP misincorporation opposite 5-methylcytosine (mC) or its oxidized derivative 5-hydroxymethylcytosine (hmC) by B-family replicative DNA polymerases with disrupted proofreading 3→5'-exonuclease activity. In addition to being less stable and pro-mutagenic themselves, cytosine modifications also increase the risk of adjacent nucleotides damage, including the formation of 8-oxo-2'-deoxyguanosine (8-oxoG), a well-known mutagenic lesion. The effect of cytosine methylation on error-prone DNA polymerases lacking proofreading activity and involved in repair and DNA translesion synthesis remains unexplored. Here we analyze the efficiency and fidelity of translesion Y-family polymerases (Pol κ, Pol η, Pol ι and REV1) and primase-polymerase PrimPol opposite mC and hmC as well as opposite 8-oxoG adjacent to mC in the TCG context. We demonstrate that epigenetic cytosine modifications suppress Pol ι and REV1 activities and lead to increasing dAMP misincorporation by PrimPol, Pol κ and Pol ι in vitro. Cytosine methylation also increases misincorporation of dAMP opposite the adjacent 8-oxoG by PrimPol, decreases the TLS activity of Pol η opposite the lesion but increases dCMP incorporation opposite 8-oxoG by REV1. Altogether, these data suggest that methylation and hydroxymethylation of cytosine alter activity and fidelity of translesion DNA polymerases.
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Affiliation(s)
- Evgeniy S Shilkin
- Institute of Molecular Genetics, National Research Center "Kurchatov Institute", Moscow 123182, Russia; Institute of Gene Biology of Russian Academy of Sciences, Moscow 119334, Russia
| | - Daria V Petrova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia; Novosibirsk State University, Novosibirsk 63009, Russia
| | - Anna A Novikova
- Institute of Molecular Genetics, National Research Center "Kurchatov Institute", Moscow 123182, Russia; Institute of Gene Biology of Russian Academy of Sciences, Moscow 119334, Russia
| | - Elizaveta O Boldinova
- Institute of Molecular Genetics, National Research Center "Kurchatov Institute", Moscow 123182, Russia; Institute of Gene Biology of Russian Academy of Sciences, Moscow 119334, Russia
| | - Dmitry O Zharkov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia; Novosibirsk State University, Novosibirsk 63009, Russia.
| | - Alena V Makarova
- Institute of Molecular Genetics, National Research Center "Kurchatov Institute", Moscow 123182, Russia; Institute of Gene Biology of Russian Academy of Sciences, Moscow 119334, Russia.
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2
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Chung WH. Signification and Application of Mutator and Antimutator Phenotype-Induced Genetic Variations in Evolutionary Adaptation and Cancer Therapeutics. J Microbiol 2023; 61:1013-1024. [PMID: 38100001 DOI: 10.1007/s12275-023-00091-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 10/30/2023] [Accepted: 11/01/2023] [Indexed: 01/11/2024]
Abstract
Mutations present a dichotomy in their implications for cellular processes. They primarily arise from DNA replication errors or damage repair processes induced by environmental challenges. Cumulative mutations underlie genetic variations and drive evolution, yet also contribute to degenerative diseases such as cancer and aging. The mutator phenotype elucidates the heightened mutation rates observed in malignant tumors. Evolutionary adaptation, analogous to bacterial and eukaryotic systems, manifests through mutator phenotypes during changing environmental conditions, highlighting the delicate balance between advantageous mutations and their potentially detrimental consequences. Leveraging the genetic tractability of Saccharomyces cerevisiae offers unique insights into mutator phenotypes and genome instability akin to human cancers. Innovative reporter assays in yeast model organisms enable the detection of diverse genome alterations, aiding a comprehensive analysis of mutator phenotypes. Despite significant advancements, our understanding of the intricate mechanisms governing spontaneous mutation rates and preserving genetic integrity remains incomplete. This review outlines various cellular pathways affecting mutation rates and explores the role of mutator genes and mutation-derived phenotypes, particularly prevalent in malignant tumor cells. An in-depth comprehension of mutator and antimutator activities in yeast and higher eukaryotes holds promise for effective cancer control strategies.
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Affiliation(s)
- Woo-Hyun Chung
- College of Pharmacy, Duksung Women's University, Seoul, 01369, Republic of Korea.
- Innovative Drug Center, Duksung Women's University, Seoul, 01369, Republic of Korea.
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3
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Lózsa R, Németh E, Gervai JZ, Márkus BG, Kollarics S, Gyüre Z, Tóth J, Simon F, Szüts D. DNA mismatch repair protects the genome from oxygen-induced replicative mutagenesis. Nucleic Acids Res 2023; 51:11040-11055. [PMID: 37791890 PMCID: PMC10639081 DOI: 10.1093/nar/gkad775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 08/23/2023] [Accepted: 09/12/2023] [Indexed: 10/05/2023] Open
Abstract
DNA mismatch repair (MMR) corrects mismatched DNA bases arising from multiple sources including polymerase errors and base damage. By detecting spontaneous mutagenesis using whole genome sequencing of cultured MMR deficient human cell lines, we show that a primary role of MMR is the repair of oxygen-induced mismatches. We found an approximately twofold higher mutation rate in MSH6 deficient DLD-1 cells or MHL1 deficient HCT116 cells exposed to atmospheric conditions as opposed to mild hypoxia, which correlated with oxidant levels measured using electron paramagnetic resonance spectroscopy. The oxygen-induced mutations were dominated by T to C base substitutions and single T deletions found primarily on the lagging strand. A broad sequence context preference, dependence on replication timing and a lack of transcriptional strand bias further suggested that oxygen-induced mutations arise from polymerase errors rather than oxidative base damage. We defined separate low and high oxygen-specific MMR deficiency mutation signatures common to the two cell lines and showed that the effect of oxygen is observable in MMR deficient cancer genomes, where it best correlates with the contribution of mutation signature SBS21. Our results imply that MMR corrects oxygen-induced genomic mismatches introduced by a replicative process in proliferating cells.
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Affiliation(s)
- Rita Lózsa
- Institute of Enzymology, Research Centre for Natural Sciences, H-1117 Budapest, Hungary
| | - Eszter Németh
- Institute of Enzymology, Research Centre for Natural Sciences, H-1117 Budapest, Hungary
| | - Judit Z Gervai
- Institute of Enzymology, Research Centre for Natural Sciences, H-1117 Budapest, Hungary
| | - Bence G Márkus
- Stavropoulos Center for Complex Quantum Matter, Department of Physics and Astronomy, University of Notre Dame, Notre Dame, IN 46556, USA
- Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, H-1525 Budapest, Hungary
- Department of Physics, Institute of Physics, Budapest University of Technology and Economics, H-1111 Budapest, Hungary
| | - Sándor Kollarics
- Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, H-1525 Budapest, Hungary
- Department of Physics, Institute of Physics, Budapest University of Technology and Economics, H-1111 Budapest, Hungary
| | - Zsolt Gyüre
- Institute of Enzymology, Research Centre for Natural Sciences, H-1117 Budapest, Hungary
- Doctoral School of Molecular Medicine, Semmelweis University, H-1085 Budapest, Hungary
- Turbine Simulated Cell Technologies, H-1027 Budapest, Hungary
| | - Judit Tóth
- Institute of Enzymology, Research Centre for Natural Sciences, H-1117 Budapest, Hungary
- Department of Applied Biotechnology and Food Science, Budapest University of Technology and Economics, H-1111 Budapest, Hungary
| | - Ferenc Simon
- Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, H-1525 Budapest, Hungary
- Department of Physics, Institute of Physics, Budapest University of Technology and Economics, H-1111 Budapest, Hungary
| | - Dávid Szüts
- Institute of Enzymology, Research Centre for Natural Sciences, H-1117 Budapest, Hungary
- National Laboratory for Drug Research and Development, H-1117 Budapest, Hungary
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4
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Vandenberg BN, Laughery MF, Cordero C, Plummer D, Mitchell D, Kreyenhagen J, Albaqshi F, Brown AJ, Mieczkowski PA, Wyrick JJ, Roberts SA. Contributions of replicative and translesion DNA polymerases to mutagenic bypass of canonical and atypical UV photoproducts. Nat Commun 2023; 14:2576. [PMID: 37142570 PMCID: PMC10160025 DOI: 10.1038/s41467-023-38255-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 04/21/2023] [Indexed: 05/06/2023] Open
Abstract
UV exposure induces a mutation signature of C > T substitutions at dipyrimidines in skin cancers. We recently identified additional UV-induced AC > TT and A > T substitutions that could respectively cause BRAF V600K and V600E oncogenic mutations. The mutagenic bypass mechanism past these atypical lesions, however, is unknown. Here, we whole genome sequenced UV-irradiated yeast and used reversion reporters to delineate the roles of replicative and translesion DNA polymerases in mutagenic bypass of UV-lesions. Our data indicates that yeast DNA polymerase eta (pol η) has varied impact on UV-induced mutations: protecting against C > T substitutions, promoting T > C and AC > TT substitutions, and not impacting A > T substitutions. Surprisingly, deletion rad30Δ increased novel UV-induced C > A substitutions at CA dinucleotides. In contrast, DNA polymerases zeta (pol ζ) and epsilon (pol ε) participated in AC > TT and A > T mutations. These results uncover lesion-specific accurate and mutagenic bypass of UV lesions, which likely contribute to key driver mutations in melanoma.
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Affiliation(s)
- Brittany N Vandenberg
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA
| | - Marian F Laughery
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA
| | - Cameron Cordero
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA
| | - Dalton Plummer
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA
| | - Debra Mitchell
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA
| | - Jordan Kreyenhagen
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA
| | - Fatimah Albaqshi
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA
| | - Alexander J Brown
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA
| | - Piotr A Mieczkowski
- Department of Genetics, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - John J Wyrick
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA.
| | - Steven A Roberts
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA.
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5
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Hakura A, Sui H, Seki Y, Sonoda J, Yoshida Y, Takagi H, Yokose S, Matsuda T, Asakura S, Nohmi T. DNA polymerase κ suppresses inflammation and inflammation-induced mutagenesis and carcinogenic potential in the colon of mice. Genes Environ 2023; 45:15. [PMID: 37087526 PMCID: PMC10122296 DOI: 10.1186/s41021-023-00272-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 04/05/2023] [Indexed: 04/24/2023] Open
Abstract
BACKGROUND Chronic inflammation induces DNA damage and promotes cell proliferation, thereby increasing the risk of cancer. DNA polymerase κ (Pol κ), involved in translesion DNA synthesis, counteracts mutagenesis induced by inflammation in the colon of mice. In the present study, we examined whether Pol κ suppressed inflammation-induced colon tumorigenesis by treating inactivated Polk knock-in (Polk-/-) mice with dextran sulfate sodium (DSS), an inducer of colon inflammation. RESULTS Male and female Polk-/- and Polk+/+ mice were administered 2% DSS in drinking water for six consecutive days, succeeded via a recovery period of 16 days, followed by 2% DSS for another two days. DSS treatment strongly induced colitis, and the severity of colitis was higher in Polk-/- mice than in Polk+/+ mice. The mice were sacrificed after 19 weeks from the initiation of the first DSS treatment and subjected to pathological examination and mutation analysis. DSS treatment induced colonic dysplasia, and the multiplicity of dysplasia was higher in Polk-/- mice than in Polk+/+mice. Some of the dysplasias in Polk-/- mice exhibited β-catenin-stained nucleus and/or cytoplasm. Mutation frequencies in the gpt reporter gene were increased by DSS treatment in Polk-/- mice, and were higher than those in Polk+/+ mice. CONCLUSIONS Pol κ suppresses inflammation and inflammation-induced dysplasia as well as inflammation-induced mutagenesis. The possible mechanisms by which Pol κ suppresses colitis- and colitis-induced dysplasia are discussed.
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Affiliation(s)
- Atsushi Hakura
- Global Drug Safety, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-Shi, Ibaraki, 300-2635, Japan.
| | - Hajime Sui
- Division of Safety Testing, Food and Drug Safety Center, Hatano Research Institute, Hadano, Kanagawa, 257-0025, Japan
| | - Yuki Seki
- Global Drug Safety, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-Shi, Ibaraki, 300-2635, Japan
| | - Jiro Sonoda
- Global Drug Safety, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-Shi, Ibaraki, 300-2635, Japan
- Present Address: Operations Department, Global Safety HQS, Eisai Co., Ltd., 4-6-10 Koishikawa, Bunkyo-Ku, Tokyo, 112-8088, Japan
| | - Yusaku Yoshida
- Biotechnical Center, Japan SLC, Inc., 3-5-1 Aoihigashi, Naka-Ku, Hamamatsu-Shi, Shizuoka, 433-8114, Japan
| | - Hisayoshi Takagi
- Biotechnical Center, Japan SLC, Inc., 3-5-1 Aoihigashi, Naka-Ku, Hamamatsu-Shi, Shizuoka, 433-8114, Japan
| | - Shigeo Yokose
- Biotechnical Center, Japan SLC, Inc., 3-5-1 Aoihigashi, Naka-Ku, Hamamatsu-Shi, Shizuoka, 433-8114, Japan
| | - Tomonari Matsuda
- Research Center for Environmental Quality Management, Kyoto University, Otsu, Shiga, 520-0811, Japan
| | - Shoji Asakura
- Global Drug Safety, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-Shi, Ibaraki, 300-2635, Japan
| | - Takehiko Nohmi
- Division of Pathology, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-Ku, Kawasaki-Shi, Kanagawa, 210-9501, Japan.
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6
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Murdocca M, Spitalieri P, D'Apice MR, Novelli G, Sangiuolo F. From cue to meaning: The involvement of POLD1 gene in DNA replication, repair and aging. Mech Ageing Dev 2023; 211:111790. [PMID: 36764464 DOI: 10.1016/j.mad.2023.111790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 02/06/2023] [Accepted: 02/06/2023] [Indexed: 02/11/2023]
Abstract
Aging is an extremely complex biological process. Aging, cancer and inflammation represent a trinity, object of many interesting researches. The accumulation of DNA damage and its consequences progressively interfere with cellular function and increase susceptibility to developing aging condition. DNA Polymerase delta (Pol δ), encoded by POLD1 gene (MIM#174761) on 19q13.3, is well implicated in many steps of the replication program and repair. Thanks to its exonuclease and polymerase activities, the enzyme is involved in the regulation of the cell cycle, DNA synthesis, and DNA damage repair processes. Damaging variants within the exonuclease domain predispose to cancers, while those occurring in the polymerase active site cause the autosomal dominant Progeroid Syndrome called MDPL, Mandibular hypoplasia, Deafness and Progeroid features with concomitant Lipodystrophy Since DNA damage represents the main cause of ageing and age-related pathologies, an overview of critical Pol δ activities will allow to better understand the associations between DNA damage and nearly every aspect of the ageing process, helping the researchers to counteract all the ageing-pathologies at the same time.
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Affiliation(s)
- Michela Murdocca
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy.
| | - Paola Spitalieri
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy.
| | | | - Giuseppe Novelli
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy; University of Nevada, Department of Pharmacology, Reno, USA; Neuromed Institute, IRCCS, Pozzilli, IS, Italy.
| | - Federica Sangiuolo
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy.
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7
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Zhou ZX, Follonier C, Lujan SA, Burkholder AB, Zakian VA, Kunkel TA. Pif1 family helicases promote mutation avoidance during DNA replication. Nucleic Acids Res 2022; 50:12844-12855. [PMID: 36533450 PMCID: PMC9825187 DOI: 10.1093/nar/gkac1127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 10/25/2022] [Accepted: 11/12/2022] [Indexed: 12/23/2022] Open
Abstract
Pif1 family 5' → 3' DNA helicases are important for replication fork progression and genome stability. The budding yeast Saccharomyces cerevisiae encodes two Pif1 family helicases, Rrm3 and Pif1, both of which are multi-functional. Here we describe novel functions for Rrm3 in promoting mutation avoidance during DNA replication. We show that loss of RRM3 results in elevated spontaneous mutations made by DNA polymerases Pols ϵ and δ, which are subject to DNA mismatch repair. The absence of RRM3 also causes higher mutagenesis by the fourth B-family DNA polymerase Pol ζ. By genome-wide analysis, we show that the mutational consequences due to loss of RRM3 vary depending on the genomic locus. Rrm3 promotes the accuracy of DNA replication by Pols ϵ and δ across the genome, and it is particularly important for preventing Pol ζ-dependent mutagenesis at tRNA genes. In addition, mutation avoidance by Rrm3 depends on its helicase activity, and Pif1 serves as a backup for Rrm3 in suppressing mutagenesis. We present evidence that the sole human Pif1 family helicase in human cells likely also promotes replication fidelity, suggesting that a role for Pif1 family helicases in mutation avoidance may be evolutionarily conserved, a possible underlying mechanism for its potential tumor-suppressor function.
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Affiliation(s)
- Zhi-Xiong Zhou
- Genome Integrity & Structural Biology Laboratory, Princeton University, Princeton, NJ 08544, USA
| | - Cindy Follonier
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Princeton, NJ 08544, USA
| | - Scott A Lujan
- Genome Integrity & Structural Biology Laboratory, Princeton University, Princeton, NJ 08544, USA
| | - Adam B Burkholder
- Integrative Bioinformatics Support Group, NIH/NIEHS, DHHS, Research Triangle Park, NC 27709, USA
| | - Virginia A Zakian
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Princeton, NJ 08544, USA
| | - Thomas A Kunkel
- Genome Integrity & Structural Biology Laboratory, Princeton University, Princeton, NJ 08544, USA
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8
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Dannenberg RL, Cardina JA, Pytko KG, Hedglin M. Tracking of progressing human DNA polymerase δ holoenzymes reveals distributions of DNA lesion bypass activities. Nucleic Acids Res 2022; 50:9893-9908. [PMID: 36107777 PMCID: PMC9508823 DOI: 10.1093/nar/gkac745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/10/2022] [Accepted: 08/23/2022] [Indexed: 11/13/2022] Open
Abstract
During DNA replication, DNA lesions in lagging strand templates are initially encountered by DNA polymerase δ (pol δ) holoenzymes comprised of pol δ and the PCNA processivity sliding clamp. These encounters are thought to stall replication of an afflicted template before the lesion, activating DNA damage tolerance (DDT) pathways that replicate the lesion and adjacent DNA sequence, allowing pol δ to resume. However, qualitative studies observed that human pol δ can replicate various DNA lesions, albeit with unknown proficiencies, which raises issues regarding the role of DDT in replicating DNA lesions. To address these issues, we re-constituted human lagging strand replication to quantitatively characterize initial encounters of pol δ holoenzymes with DNA lesions. The results indicate pol δ holoenzymes support dNTP incorporation opposite and beyond multiple lesions and the extent of these activities depends on the lesion and pol δ proofreading. Furthermore, after encountering a given DNA lesion, subsequent dissociation of pol δ is distributed around the lesion and a portion does not dissociate. The distributions of these events are dependent on the lesion and pol δ proofreading. Collectively, these results reveal complexity and heterogeneity in the replication of lagging strand DNA lesions, significantly advancing our understanding of human DDT.
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Affiliation(s)
- Rachel L Dannenberg
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
| | - Joseph A Cardina
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
| | - Kara G Pytko
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
| | - Mark Hedglin
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
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9
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Zhou ZX, Kunkel TA. Extrinsic proofreading. DNA Repair (Amst) 2022; 117:103369. [PMID: 35850061 PMCID: PMC9561950 DOI: 10.1016/j.dnarep.2022.103369] [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: 03/27/2022] [Revised: 07/01/2022] [Accepted: 07/02/2022] [Indexed: 11/24/2022]
Abstract
The high fidelity of replication of the nuclear DNA genome in eukaryotes involves three processes. Correct rather than incorrect dNTPs are almost always incorporated by the three major replicases, DNA polymerases α, δ and ε. When an incorrect base is occasionally inserted, the latter Pols δ and ε also have a 3 ´ to 5 ´ exonuclease activity that can remove the mismatch to allow correct DNA synthesis to proceed. Lastly, rare mismatches that escape proofreading activity and are present in newly replicated DNA can be removed by DNA mismatch repair. In this review, we consider evidence supporting the hypothesis that the second mechanism, proofreading, can operate in two different ways. Primer terminal mismatches made by either Pol δ or Pol ε can be 'intrinsically' proofread. This mechanism occurs by direct transfer of a misinserted base made at the polymerase active site to the exonuclease active site that is located a short distance away. Intrinsic proofreading allows mismatch excision without intervening enzyme dissociation. Alternatively, considerable evidence suggests that mismatches made by any of the three replicases can also be proofread by 'extrinsic' proofreading by Pol δ. Extrinsic proofreading occurs when a mismatch made by any of the three replicases is initially abandoned, thereby allowing the exonuclease active site of Pol δ to bind directly to and remove the mismatch before replication continues. Here we review the evidence that extrinsic proofreading significantly enhances the fidelity of nuclear DNA replication, and we then briefly consider the implications of this process for evolution and disease.
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Affiliation(s)
- Zhi-Xiong Zhou
- Genome Integrity Structural Biology Laboratory, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC 27709, USA
| | - Thomas A Kunkel
- Genome Integrity Structural Biology Laboratory, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC 27709, USA.
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10
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Barnes RP, de Rosa M, Thosar SA, Detwiler AC, Roginskaya V, Van Houten B, Bruchez MP, Stewart-Ornstein J, Opresko PL. Telomeric 8-oxo-guanine drives rapid premature senescence in the absence of telomere shortening. Nat Struct Mol Biol 2022; 29:639-652. [PMID: 35773409 PMCID: PMC9287163 DOI: 10.1038/s41594-022-00790-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 05/16/2022] [Indexed: 01/10/2023]
Abstract
Oxidative stress is a primary cause of cellular senescence and contributes to the etiology of numerous human diseases. Oxidative damage to telomeric DNA has been proposed to cause premature senescence by accelerating telomere shortening. Here, we tested this model directly using a precision chemoptogenetic tool to produce the common lesion 8-oxo-guanine (8oxoG) exclusively at telomeres in human fibroblasts and epithelial cells. A single induction of telomeric 8oxoG is sufficient to trigger multiple hallmarks of p53-dependent senescence. Telomeric 8oxoG activates ATM and ATR signaling, and enriches for markers of telomere dysfunction in replicating, but not quiescent cells. Acute 8oxoG production fails to shorten telomeres, but rather generates fragile sites and mitotic DNA synthesis at telomeres, indicative of impaired replication. Based on our results, we propose that oxidative stress promotes rapid senescence by producing oxidative base lesions that drive replication-dependent telomere fragility and dysfunction in the absence of shortening and shelterin loss. This study uncovers a new mechanism linking oxidative stress to telomere-driven senescence. A common oxidative lesion at telomeres causes rapid premature cellular aging by inducing telomere fragility, rather than telomere shortening.
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Affiliation(s)
- Ryan P Barnes
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA.,UPMC Hillman Cancer Center, Pittsburgh, PA, USA
| | - Mariarosaria de Rosa
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA.,UPMC Hillman Cancer Center, Pittsburgh, PA, USA
| | - Sanjana A Thosar
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA.,UPMC Hillman Cancer Center, Pittsburgh, PA, USA
| | - Ariana C Detwiler
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA.,UPMC Hillman Cancer Center, Pittsburgh, PA, USA
| | - Vera Roginskaya
- UPMC Hillman Cancer Center, Pittsburgh, PA, USA.,Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Bennett Van Houten
- UPMC Hillman Cancer Center, Pittsburgh, PA, USA.,Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Marcel P Bruchez
- Departments of Biological Sciences and Chemistry and the Molecular Biosensors and Imaging Center, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Jacob Stewart-Ornstein
- UPMC Hillman Cancer Center, Pittsburgh, PA, USA.,Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Patricia L Opresko
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA. .,UPMC Hillman Cancer Center, Pittsburgh, PA, USA. .,Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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11
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Franco I, Revêchon G, Eriksson M. Challenges of proving a causal role of somatic mutations in the aging process. Aging Cell 2022; 21:e13613. [PMID: 35435316 PMCID: PMC9124308 DOI: 10.1111/acel.13613] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/25/2022] [Accepted: 04/03/2022] [Indexed: 12/21/2022] Open
Abstract
Aging is accompanied by the progressive accumulation of permanent changes to the genomic sequence, termed somatic mutations. Small mutations, including single‐base substitutions and insertions/deletions, are key determinants of the malignant transformations leading to cancer, but their role as initiators of other age‐related phenotypes is controversial. Here, we present recent advances in the study of somatic mutagenesis in aging tissues and posit that the current uncertainty about its causal effects in the aging process is due to technological and methodological weaknesses. We highlight classical and novel experimental systems, including premature aging syndromes, that could be used to model the increase of somatic mutation burden and understand its functional role. It is important that studies are designed to take into account the biological context and peculiarities of each tissue and that the downstream impact of somatic mutation accumulation is measured by methods able to resolve subtle cellular changes.
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Affiliation(s)
- Irene Franco
- Cystic Kidney Disorders Unit Division of Genetics and Cell Biology IRCCS Ospedale San Raffaele Milan Italy
| | - Gwladys Revêchon
- Department of Biosciences and Nutrition Center for Innovative Medicine Karolinska Institutet Huddinge Sweden
| | - Maria Eriksson
- Department of Biosciences and Nutrition Center for Innovative Medicine Karolinska Institutet Huddinge Sweden
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12
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Zhou ZX, Lujan SA, Burkholder AB, St. Charles J, Dahl J, Farrell CE, Williams JS, Kunkel TA. How asymmetric DNA replication achieves symmetrical fidelity. Nat Struct Mol Biol 2021; 28:1020-1028. [PMID: 34887558 PMCID: PMC8815454 DOI: 10.1038/s41594-021-00691-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 10/22/2021] [Indexed: 11/09/2022]
Abstract
Accurate DNA replication of an undamaged template depends on polymerase selectivity for matched nucleotides, exonucleolytic proofreading of mismatches, and removal of remaining mismatches via DNA mismatch repair (MMR). DNA polymerases (Pols) δ and ε have 3'-5' exonucleases into which mismatches are partitioned for excision in cis (intrinsic proofreading). Here we provide strong evidence that Pol δ can extrinsically proofread mismatches made by itself and those made by Pol ε, independently of both Pol δ's polymerization activity and MMR. Extrinsic proofreading across the genome is remarkably efficient. We report, with unprecedented accuracy, in vivo contributions of nucleotide selectivity, proofreading, and MMR to the fidelity of DNA replication in Saccharomyces cerevisiae. We show that extrinsic proofreading by Pol δ improves and balances the fidelity of the two DNA strands. Together, we depict a comprehensive picture of how nucleotide selectivity, proofreading, and MMR cooperate to achieve high and symmetrical fidelity on the two strands.
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Affiliation(s)
- Zhi-Xiong Zhou
- Genome Integrity & Structural Biology Laboratory, NIH/NIEHS, DHHS, Research Triangle Park, North Carolina, USA
| | - Scott A. Lujan
- Genome Integrity & Structural Biology Laboratory, NIH/NIEHS, DHHS, Research Triangle Park, North Carolina, USA
| | - Adam B. Burkholder
- Integrative Bioinformatics Support Group, NIH/NIEHS, DHHS, Research Triangle Park, North Carolina, USA
| | - Jordan St. Charles
- Genome Integrity & Structural Biology Laboratory, NIH/NIEHS, DHHS, Research Triangle Park, North Carolina, USA
| | - Joseph Dahl
- Genome Integrity & Structural Biology Laboratory, NIH/NIEHS, DHHS, Research Triangle Park, North Carolina, USA
| | - Corinne E. Farrell
- Genome Integrity & Structural Biology Laboratory, NIH/NIEHS, DHHS, Research Triangle Park, North Carolina, USA
| | - Jessica S. Williams
- Genome Integrity & Structural Biology Laboratory, NIH/NIEHS, DHHS, Research Triangle Park, North Carolina, USA
| | - Thomas A. Kunkel
- Genome Integrity & Structural Biology Laboratory, NIH/NIEHS, DHHS, Research Triangle Park, North Carolina, USA
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13
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Robinson PS, Coorens THH, Palles C, Mitchell E, Abascal F, Olafsson S, Lee BCH, Lawson ARJ, Lee-Six H, Moore L, Sanders MA, Hewinson J, Martin L, Pinna CMA, Galavotti S, Rahbari R, Campbell PJ, Martincorena I, Tomlinson I, Stratton MR. Increased somatic mutation burdens in normal human cells due to defective DNA polymerases. Nat Genet 2021; 53:1434-1442. [PMID: 34594041 PMCID: PMC8492474 DOI: 10.1038/s41588-021-00930-y] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 07/28/2021] [Indexed: 02/08/2023]
Abstract
Mutation accumulation in somatic cells contributes to cancer development and is proposed as a cause of aging. DNA polymerases Pol ε and Pol δ replicate DNA during cell division. However, in some cancers, defective proofreading due to acquired POLE/POLD1 exonuclease domain mutations causes markedly elevated somatic mutation burdens with distinctive mutational signatures. Germline POLE/POLD1 mutations cause familial cancer predisposition. Here, we sequenced normal tissue and tumor DNA from individuals with germline POLE/POLD1 mutations. Increased mutation burdens with characteristic mutational signatures were found in normal adult somatic cell types, during early embryogenesis and in sperm. Thus human physiology can tolerate ubiquitously elevated mutation burdens. Except for increased cancer risk, individuals with germline POLE/POLD1 mutations do not exhibit overt features of premature aging. These results do not support a model in which all features of aging are attributable to widespread cell malfunction directly resulting from somatic mutation burdens accrued during life.
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Affiliation(s)
- Philip S Robinson
- Wellcome Sanger Institute, Hinxton, UK
- Department of Paediatrics, University of Cambridge, Cambridge, UK
| | | | - Claire Palles
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | | | | | | | - Bernard C H Lee
- Wellcome Sanger Institute, Hinxton, UK
- Hereditary Gastrointestinal Cancer Genetic Diagnosis Laboratory, Department of Pathology, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong
| | | | | | | | - Mathijs A Sanders
- Wellcome Sanger Institute, Hinxton, UK
- Department of Haematology, Erasmus University Medical Centre, Rotterdam, the Netherlands
| | | | - Lynn Martin
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Claudia M A Pinna
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Sara Galavotti
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | | | | | | | - Ian Tomlinson
- Edinburgh Cancer Research Centre, IGMM, University of Edinburgh, Edinburgh, UK.
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14
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Wang Y, Chen Y, Wang C, Yang M, Wang Y, Bao L, Wang JE, Kim B, Chan KY, Xu W, Capota E, Ortega J, Nijhawan D, Li GM, Luo W, Wang Y. MIF is a 3' flap nuclease that facilitates DNA replication and promotes tumor growth. Nat Commun 2021; 12:2954. [PMID: 34012010 PMCID: PMC8134555 DOI: 10.1038/s41467-021-23264-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Accepted: 04/20/2021] [Indexed: 11/13/2022] Open
Abstract
How cancer cells cope with high levels of replication stress during rapid proliferation is currently unclear. Here, we show that macrophage migration inhibitory factor (MIF) is a 3’ flap nuclease that translocates to the nucleus in S phase. Poly(ADP-ribose) polymerase 1 co-localizes with MIF to the DNA replication fork, where MIF nuclease activity is required to resolve replication stress and facilitates tumor growth. MIF loss in cancer cells leads to mutation frequency increases, cell cycle delays and DNA synthesis and cell growth inhibition, which can be rescued by restoring MIF, but not nuclease-deficient MIF mutant. MIF is significantly upregulated in breast tumors and correlates with poor overall survival in patients. We propose that MIF is a unique 3’ nuclease, excises flaps at the immediate 3’ end during DNA synthesis and favors cancer cells evading replication stress-induced threat for their growth. Replication stress is associated with cancer formation and progression. Here the authors reveal that the macrophage migration inhibitory factor (MIF) functions as 3’ flap nuclease involved in resolving replication stress affecting overall tumor progression.
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Affiliation(s)
- Yijie Wang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Yan Chen
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Chenliang Wang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Mingming Yang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Yanan Wang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Lei Bao
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Jennifer E Wang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - BongWoo Kim
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Kara Y Chan
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Weizhi Xu
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Emanuela Capota
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA
| | - Janice Ortega
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Deepak Nijhawan
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA
| | - Guo-Min Li
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Weibo Luo
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Yingfei Wang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA. .,Department of Neurology, UT Southwestern Medical Center, Dallas, TX, USA.
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15
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Guilliam TA, Yeeles JT. The eukaryotic replisome tolerates leading-strand base damage by replicase switching. EMBO J 2021; 40:e107037. [PMID: 33555053 PMCID: PMC7917549 DOI: 10.15252/embj.2020107037] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 12/09/2020] [Accepted: 01/07/2021] [Indexed: 01/15/2023] Open
Abstract
The high‐fidelity replicative DNA polymerases, Pol ε and Pol δ, are generally thought to be poorly equipped to replicate damaged DNA. Direct and complete replication of a damaged template therefore typically requires the activity of low‐fidelity translesion synthesis (TLS) polymerases. Here we show that a yeast replisome, reconstituted with purified proteins, is inherently tolerant of the common oxidative lesion thymine glycol (Tg). Surprisingly, leading‐strand Tg was bypassed efficiently in the presence and absence of the TLS machinery. Our data reveal that following helicase–polymerase uncoupling a switch from Pol ε, the canonical leading‐strand replicase, to the lagging‐strand replicase Pol δ, facilitates rapid, efficient and error‐free lesion bypass at physiological nucleotide levels. This replicase switch mechanism also promotes bypass of the unrelated oxidative lesion, 8‐oxoguanine. We propose that replicase switching may promote continued leading‐strand synthesis whenever the replisome encounters leading‐strand damage that is bypassed more efficiently by Pol δ than by Pol ε.
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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 Tp Yeeles
- Division of Protein and Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
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16
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Suzuki T, Sassa A, Grúz P, Gupta RC, Johnson F, Adachi N, Nohmi T. Error-prone bypass patch by a low-fidelity variant of DNA polymerase zeta in human cells. DNA Repair (Amst) 2021; 100:103052. [PMID: 33607474 DOI: 10.1016/j.dnarep.2021.103052] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 01/16/2021] [Accepted: 01/20/2021] [Indexed: 11/15/2022]
Abstract
DNA polymerase ζ (Pol ζ) is a specialized Pol that is involved in translesion DNA synthesis (TLS), in particular, in the extension of primer DNA after bypassing DNA lesions. Previously, we established human cells that express a variant form of Pol ζ with an amino acid change of leucine 2618 to methionine (L2618M) in the catalytic subunit REV3L (DNA Repair, 45, 34-43, 2016). This amino acid change made the cells more sensitive to the mutagenicity of benzo[a]pyrene diol epoxide (BPDE). In this study, we embedded BPDE-N2-guanine at a defined position in the supF gene on the shuttle plasmid and introduced it to REV3 L2618M cells or the wild-type (WT) cells to examine how far Pol ζ L2618M extends the primer DNA after bypassing the lesion. The adduct induced primarily G to T and G to C at the adducted site in both cell lines, but generated additional sequence changes such as base substitutions, deletions and additions in the extension patch much more often in REV3 L2618M cells than in the WT cells. Mutations in the extension patch in REV3 L2618M cells occurred most often within 10 bps from the adducted site. Then, the number of mutations gradually decreased and no mutations were observed between 30 and 40 bps from the lesion. We concluded that human Pol ζ L2618M and perhaps WT Pol ζ extend the primer DNA up to approximately 30 bps from the lesion in vivo. The possibility of involvement of Pol ζ L2618M in the insertion step of TLS is discussed.
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Affiliation(s)
- Tetsuya Suzuki
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa, 210-9501, Japan.
| | - Akira Sassa
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa, 210-9501, Japan
| | - Petr Grúz
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa, 210-9501, Japan
| | - Ramesh C Gupta
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, 11794-3400, NY, United States
| | - Francis Johnson
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, 11794-3400, NY, United States
| | - Noritaka Adachi
- Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, Kanagawa, 236-0027, Japan
| | - Takehiko Nohmi
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa, 210-9501, Japan
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17
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Kojima K, Ooka M, Abe T, Hirota K. Pold4, the fourth subunit of replicative polymerase δ, suppresses gene conversion in the immunoglobulin-variable gene in avian DT40 cells. DNA Repair (Amst) 2021; 100:103056. [PMID: 33588156 DOI: 10.1016/j.dnarep.2021.103056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/26/2021] [Accepted: 01/28/2021] [Indexed: 10/22/2022]
Abstract
The replicative polymerase δ (Polδ), consisting of four subunits, plays a pivotal role in chromosomal replication. Pold4, the smallest subunit of Polδ, is believed to contribute to the regulation of replication by facilitating repair in response to DNA damage. However, that contribution has not been fully elucidated. We here show that Pold4 contributes to the suppression of gene conversion in immunoglobulin-variable (IgV) gene diversification in the chicken DT40 lymphocyte cell line, where gene conversion diversifies the IgV gene through intragenic homologous recombination (HR) between diverged pseudo-V segments. IgV gene conversion is initiated by activation-induced cytidine deaminase-mediated uracil formation in the IgV gene, which in turn converts into an abasic site, leading to replication arrest. POLD4-/- cells exhibited an increased rate of IgV gene conversion. Moreover, the gene-conversion tract was lengthened and the usage of pseudo-V segments was altered, showing a preference, to use the diverged sequence as a donor in POLD4-/- cells. These data suggest that Pold4 is involved in the regulation of HR-mediated gene conversion in IgV diversification. By contrast, the rate in HR-mediated, sister-chromatid exchange and gene-targeting induced by an I-SceI endonclease-mediated DNA double-strand break exhibited by POLD4-/- cells was indistinguishable from that by wild-type cells. These findings indicate that the functionality of general HR is preserved in POLD4-/- cells. In conclusion, Pold4 is involved in the suppression of IgV-gene conversion without affecting the general functionality of HR.
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Affiliation(s)
- Kota Kojima
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Minamiosawa 1-1, Hachioji-shi, Tokyo, 192-0397, Japan
| | - Masato Ooka
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Minamiosawa 1-1, Hachioji-shi, Tokyo, 192-0397, Japan
| | - Takuya Abe
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Minamiosawa 1-1, Hachioji-shi, Tokyo, 192-0397, Japan
| | - Kouji Hirota
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Minamiosawa 1-1, Hachioji-shi, Tokyo, 192-0397, Japan.
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18
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Visualizing Rev1 catalyze protein-template DNA synthesis. Proc Natl Acad Sci U S A 2020; 117:25494-25504. [PMID: 32999062 DOI: 10.1073/pnas.2010484117] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
During DNA replication, replicative DNA polymerases may encounter DNA lesions, which can stall replication forks. One way to prevent replication fork stalling is through the recruitment of specialized translesion synthesis (TLS) polymerases that have evolved to incorporate nucleotides opposite DNA lesions. Rev1 is a specialized TLS polymerase that bypasses abasic sites, as well as minor-groove and exocyclic guanine adducts. Lesion bypass is accomplished using a unique protein-template mechanism in which the templating base is evicted from the DNA helix and the incoming dCTP hydrogen bonds with an arginine side chain of Rev1. To understand the protein-template mechanism at an atomic level, we employed a combination of time-lapse X-ray crystallography, molecular dynamics simulations, and DNA enzymology on the Saccharomyces cerevisiae Rev1 protein. We find that Rev1 evicts the templating base from the DNA helix prior to binding the incoming nucleotide. Binding the incoming nucleotide changes the conformation of the DNA substrate to orient it for nucleotidyl transfer, although this is not coupled to large structural changes in Rev1 like those observed with other DNA polymerases. Moreover, we found that following nucleotide incorporation, Rev1 converts the pyrophosphate product to two monophosphates, which drives the reaction in the forward direction and prevents pyrophosphorolysis. Following nucleotide incorporation, the hydrogen bonds between the incorporated nucleotide and the arginine side chain are broken, but the templating base remains extrahelical. These postcatalytic changes prevent potentially mutagenic processive synthesis by Rev1 and facilitate dissociation of the DNA product from the enzyme.
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19
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Drosopoulos WC, Vierra DA, Kenworthy CA, Coleman RA, Schildkraut CL. Dynamic Assembly and Disassembly of the Human DNA Polymerase δ Holoenzyme on the Genome In Vivo. Cell Rep 2020; 30:1329-1341.e5. [PMID: 32023453 PMCID: PMC7597369 DOI: 10.1016/j.celrep.2019.12.101] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 11/21/2019] [Accepted: 12/30/2019] [Indexed: 12/15/2022] Open
Abstract
Human DNA polymerase delta (Pol δ) forms a holoenzyme complex with the DNA sliding clamp proliferating cell nuclear antigen (PCNA) to perform its essential roles in genome replication. Here, we utilize live-cell single-molecule tracking to monitor Pol δ holoenzyme interaction with the genome in real time. We find holoenzyme assembly and disassembly in vivo are highly dynamic and ordered. PCNA generally loads onto the genome before Pol δ. Once assembled, the holoenzyme has a relatively short lifetime on the genome, implying multiple Pol δ binding events may be needed to synthesize an Okazaki fragment. During disassembly, Pol δ dissociation generally precedes PCNA unloading. We also find that Pol δ p125, the catalytic subunit of the holoenzyme, is maintained at a constant cellular level, indicating an active mechanism for control of Pol δ levels in vivo. Collectively, our studies reveal that Pol δ holoenzyme assembly and disassembly follow a predominant pathway in vivo; however, alternate pathways are observed.
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Affiliation(s)
- William C Drosopoulos
- Department of Cell Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 USA.
| | - David A Vierra
- Department of Cell Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 USA
| | - Charles A Kenworthy
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 USA
| | - Robert A Coleman
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 USA.
| | - Carl L Schildkraut
- Department of Cell Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 USA.
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20
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Hoitsma NM, Whitaker AM, Schaich MA, Smith MR, Fairlamb MS, Freudenthal BD. Structure and function relationships in mammalian DNA polymerases. Cell Mol Life Sci 2020; 77:35-59. [PMID: 31722068 PMCID: PMC7050493 DOI: 10.1007/s00018-019-03368-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 10/11/2019] [Accepted: 10/31/2019] [Indexed: 12/19/2022]
Abstract
DNA polymerases are vital for the synthesis of new DNA strands. Since the discovery of DNA polymerase I in Escherichia coli, a diverse library of mammalian DNA polymerases involved in DNA replication, DNA repair, antibody generation, and cell checkpoint signaling has emerged. While the unique functions of these DNA polymerases are differentiated by their association with accessory factors and/or the presence of distinctive catalytic domains, atomic resolution structures of DNA polymerases in complex with their DNA substrates have revealed mechanistic subtleties that contribute to their specialization. In this review, the structure and function of all 15 mammalian DNA polymerases from families B, Y, X, and A will be reviewed and discussed with special emphasis on the insights gleaned from recently published atomic resolution structures.
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Affiliation(s)
- Nicole M Hoitsma
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Amy M Whitaker
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Matthew A Schaich
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Mallory R Smith
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Max S Fairlamb
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Bret D Freudenthal
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA.
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21
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Nohmi T, Matsumoto K. Effects of DNA polymerase kappa and mismatch repair on dose-responses of chromosome aberrations induced by three oxidative genotoxins in human cells. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2020; 61:193-199. [PMID: 31294882 DOI: 10.1002/em.22315] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 06/25/2019] [Accepted: 06/27/2019] [Indexed: 06/09/2023]
Abstract
Genotoxic carcinogens are regulated under the policy that there is no threshold or safe dose. It has been pointed out, however, that self-defense mechanisms, such as detoxification, DNA repair, and error-free translesion synthesis, may protect chromosome DNA from genotoxic insults, thereby constituting practical threshold. In this study, we examined dose responses of chromosome aberrations induced by three oxidative genotoxins, that is, hydrogen peroxide (H2 O2 ), menadione and paraquat, with or without DNA polymerase kappa (Polκ) activities and mismatch repair capacities in human cells. Polκ is involved in translesion synthesis across DNA damage and mismatch repair is responsible for correction of base-base mismatch in DNA. Polκ activity of the cells was inactivated either by point mutations in the catalytically essential amino acids (catalytically dead or CD) or by deletion of the POLK gene (knockout or KO). In the absence of mismatch repair, frequencies of chromosome aberrations induced by H2 O2 and menadione were not significantly different among CD, KO, and the wild type (WT) cells. In the presence of mismatch repair, however, cytotoxicity and clastogenicity were enhanced and Polκ modulated the sensitivity of the cells. No-observed-genotoxic-effect-levels (NOGELs) for H2 O2 and menadione were CD = KO < WT cells. In contrast, the sensitivities of the cells to paraquat were not significantly affected by the status of mismatch repair or Polκ activity. The results suggest that mismatch repair and Polκ coordinately modulate NOGELs for the clastogenicity of H2 O2 and menadione and also that DNA lesion(s) responsible for paraquat-induced chromosome aberrations are different from those induced by H2 O2 and menadione. Environ. Mol. Mutagen. 61:193-199, 2020. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Takehiko Nohmi
- Biological Safety Research Center, National Institute of Health Sciences, Kawasaki-shi, Kanagawa, Japan
| | - Kyomu Matsumoto
- Toxicology Division, The Institute of Environmental Toxicology, Joso-shi, Ibaraki, Japan
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22
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Yoshimura A, Oikawa M, Jinbo H, Hasegawa Y, Enomoto T, Seki M. WRNIP1 Controls the Amount of PrimPol. Biol Pharm Bull 2019; 42:764-769. [PMID: 31061318 DOI: 10.1248/bpb.b18-00955] [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] [Indexed: 11/22/2022]
Abstract
Werner helicase-interacting protein 1 (WRNIP1) was originally identified as a protein that interacts with WRN, the product of the gene responsible for Werner syndrome. Our previous studies suggested that WRNIP1 is implicated in translesion synthesis (TLS), a process in which specialized TLS polymerases replace replicative DNA polymerase and take over DNA synthesis on damaged templates. We proposed that a novel error-free pathway involving DNA polymerase δ and primase-polymerase (PrimPol) functions to synthesize DNA on UV-damaged DNA templates in the absence of WRNIP1 and the TLS polymerase Polη. Hence, in the current study, we analyzed the relationship between WRNIP1 and PrimPol. We found that WRNIP1 and PrimPol form a complex in cells. PrimPol protein expression was reduced in cells overexpressing WRNIP1, but was increased in WRNIP1-depleted cells. The WRNIP1-mediated reduction in the amount of PrimPol was suppressed by treatment of the cells with proteasome inhibitors, suggesting that WRNIP1 is involved in the degradation of PrimPol via the proteasome.
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Affiliation(s)
- Akari Yoshimura
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University
| | - Mizuho Oikawa
- Molecular Cell Biology Laboratory, Research Institute of Pharmaceutical Sciences, Faculty of Pharmacy, Musashino University
| | - Hitomi Jinbo
- Molecular Cell Biology Laboratory, Research Institute of Pharmaceutical Sciences, Faculty of Pharmacy, Musashino University
| | - Yuri Hasegawa
- Molecular Cell Biology Laboratory, Research Institute of Pharmaceutical Sciences, Faculty of Pharmacy, Musashino University
| | - Takemi Enomoto
- Molecular Cell Biology Laboratory, Research Institute of Pharmaceutical Sciences, Faculty of Pharmacy, Musashino University
| | - Masayuki Seki
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University
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23
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Natali F, Rancati G. The Mutator Phenotype: Adapting Microbial Evolution to Cancer Biology. Front Genet 2019; 10:713. [PMID: 31447882 PMCID: PMC6691094 DOI: 10.3389/fgene.2019.00713] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 07/05/2019] [Indexed: 01/07/2023] Open
Abstract
The mutator phenotype hypothesis was postulated almost 40 years ago to reconcile the observation that while cancer cells display widespread mutational burden, acquisition of mutations in non-transformed cells is a rare event. Moreover, it also suggested that cancer evolution could be fostered by increased genome instability. Given the evolutionary conservation throughout the tree of life and the genetic tractability of model organisms, yeast and bacterial species pioneered studies to dissect the functions of genes required for genome maintenance (caretaker genes) or for cell growth control (gatekeeper genes). In this review, we first provide an overview of what we learned from model organisms about the roles of these genes and the genome instability that arises as a consequence of their dysregulation. We then discuss our current understanding of how mutator phenotypes shape the evolution of bacteria and yeast species. We end by bringing clinical evidence that lessons learned from single-cell organisms can be applied to tumor evolution.
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Affiliation(s)
- Federica Natali
- Institute of Medical Biology (IMB), Agency for Science, Technology and Research (ASTAR), Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Giulia Rancati
- Institute of Medical Biology (IMB), Agency for Science, Technology and Research (ASTAR), Singapore, Singapore
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Jozwiakowski SK, Kummer S, Gari K. Human DNA polymerase delta requires an iron-sulfur cluster for high-fidelity DNA synthesis. Life Sci Alliance 2019; 2:2/4/e201900321. [PMID: 31278166 PMCID: PMC6613617 DOI: 10.26508/lsa.201900321] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 06/26/2019] [Accepted: 06/27/2019] [Indexed: 01/10/2023] Open
Abstract
The iron–sulfur cluster in human DNA polymerase delta has an impact on DNA polymerase and exonuclease activities and can hence influence the fidelity of DNA synthesis. Replication of eukaryotic genomes relies on the family B DNA polymerases Pol α, Pol δ, and Pol ε. All of these enzymes coordinate an iron–sulfur (FeS) cluster, but the function of this cofactor has remained largely unclear. Here, we show that the FeS cluster in the catalytic subunit of human Pol δ is coordinated by four invariant cysteines of the C-terminal CysB motif. FeS cluster loss causes a partial destabilisation of the four-subunit enzyme, a defect in double-stranded DNA binding, and compromised polymerase and exonuclease activities. Importantly, complex stability, DNA binding, and enzymatic activities are restored in the presence of proliferating cell nuclear antigen. We further show that also more subtle changes to the FeS cluster-binding pocket that do not abolish FeS cluster binding can have repercussions on the distant exonuclease domain and render the enzyme error-prone. Our data hence suggest that the FeS cluster in human Pol δ is an important co-factor that despite its C-terminal location has an impact on both DNA polymerase and exonuclease activities, and can influence the fidelity of DNA synthesis.
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Affiliation(s)
| | - Sandra Kummer
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Kerstin Gari
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
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25
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Abstract
7,8-Dihydro-8-oxoguanine (oxoG) is the most abundant oxidative DNA lesion with dual coding properties. It forms both Watson–Crick (anti)oxoG:(anti)C and Hoogsteen (syn)oxoG:(anti)A base pairs without a significant distortion of a B-DNA helix. DNA polymerases bypass oxoG but the accuracy of nucleotide incorporation opposite the lesion varies depending on the polymerase-specific interactions with the templating oxoG and incoming nucleotides. High-fidelity replicative DNA polymerases read oxoG as a cognate base for A while treating oxoG:C as a mismatch. The mutagenic effects of oxoG in the cell are alleviated by specific systems for DNA repair and nucleotide pool sanitization, preventing mutagenesis from both direct DNA oxidation and oxodGMP incorporation. DNA translesion synthesis could provide an additional protective mechanism against oxoG mutagenesis in cells. Several human DNA polymerases of the X- and Y-families efficiently and accurately incorporate nucleotides opposite oxoG. In this review, we address the mutagenic potential of oxoG in cells and discuss the structural basis for oxoG bypass by different DNA polymerases and the mechanisms of the recognition of oxoG by DNA glycosylases and dNTP hydrolases.
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26
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Hakura A, Sui H, Sonoda J, Matsuda T, Nohmi T. DNA polymerase kappa counteracts inflammation-induced mutagenesis in multiple organs of mice. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2019; 60:320-330. [PMID: 30620413 DOI: 10.1002/em.22272] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 12/26/2018] [Accepted: 12/28/2018] [Indexed: 05/07/2023]
Abstract
In vitro studies indicate that DNA polymerase kappa (Polκ) is able to accurately and efficiently perform DNA synthesis using templates containing various types of DNA damage, including benzo[a]pyrene (BP)-induced N2 -deoxyguanosine adducts. In this study, we examined sensitivity of inactivated Polk knock-in (Polk-/- ) mice to BP carcinogenicity in the colon by administering an oral dose of BP plus dextran sulfate sodium (DSS), an inflammation causing promoter of carcinogenesis. Although colon cancer was successfully induced by BP plus DSS, there was no significant difference in tumor incidence or multiplicity between Polk-/- and Polk+/+ mice. Malignant lymphoma was induced in thymus by the treatment only in Polk-/- mice, but it lacked statistical significance. Mutant frequencies (MFs) in the gpt reporter gene were strongly enhanced in colon; almost to the same extent in both types of mice. Micronucleus formation in bone marrow at the high dose of BP and DNA adducts in colon and lung was not significantly different between two types of mice. Surprisingly, however, Polk-/- mice exhibited significantly higher MFs in colon and lung than did Polk+/+ mice when they were treated with DSS alone. The most prominent mutation induced by DSS treatment was G:C to C:G transversion, whose specific MF in proximal colon was 30 times higher in Polk-/- than in Polk+/+ mice. DSS alone did not enhance MF at all in Polk+/+ mice. The results indicate that Polκ does not suppress BP-induced mutagenesis and carcinogenesis in the colon, but counteracts inflammation-induced mutagenesis in multiple organs. Environ. Mol. Mutagen. 60:320-330, 2019. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Atsushi Hakura
- Tsukuba Drug Safety, Eisai Co., Ltd., Tsukuba-shi, Ibaraki, Japan
| | - Hajime Sui
- Food and Drug Safety Center, Hatano Research Institute, Hadano, Kanagawa, Japan
| | - Jiro Sonoda
- GLP, Eisai Co., Ltd., Tsukuba-shi, Ibaraki, Japan
| | - Tomonari Matsuda
- Research Center for Environmental Quality Management, Kyoto University, Otsu, Shiga, Japan
| | - Takehiko Nohmi
- Biological Safety Research Center, National Institute of Health Sciences, Kawasaki-ku, Kawasaki-shi, Kanagawa, Japan
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27
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Khandagale P, Peroumal D, Manohar K, Acharya N. Human DNA polymerase delta is a pentameric holoenzyme with a dimeric p12 subunit. Life Sci Alliance 2019; 2:2/2/e201900323. [PMID: 30885984 PMCID: PMC6424025 DOI: 10.26508/lsa.201900323] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 03/04/2019] [Accepted: 03/11/2019] [Indexed: 01/07/2023] Open
Abstract
The subunit p12 of human DNA polymerase delta (hPolδ) can dimerize, facilitating its interaction with PCNA and suggesting that hPolδ exists in a pentameric form in the cell. Human DNA polymerase delta (Polδ), a holoenzyme consisting of p125, p50, p68, and p12 subunits, plays an essential role in DNA replication, repair, and recombination. Herein, using multiple physicochemical and cellular approaches, we found that the p12 protein forms a dimer in solution. In vitro reconstitution and pull down of cellular Polδ by tagged p12 substantiate the pentameric nature of this critical holoenzyme. Furthermore, a consensus proliferating nuclear antigen (PCNA) interaction protein motif at the extreme carboxyl-terminal tail and a homodimerization domain at the amino terminus of the p12 subunit were identified. Mutational analyses of these motifs in p12 suggest that dimerization facilitates p12 binding to the interdomain connecting loop of PCNA. In addition, we observed that oligomerization of the smallest subunit of Polδ is evolutionarily conserved as Cdm1 of Schizosaccharomyces pombe also dimerizes. Thus, we suggest that human Polδ is a pentameric complex with a dimeric p12 subunit, and discuss implications of p12 dimerization in enzyme architecture and PCNA interaction during DNA replication.
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Affiliation(s)
- Prashant Khandagale
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
| | - Doureradjou Peroumal
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
| | - Kodavati Manohar
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
| | - Narottam Acharya
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
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28
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Zhang M, Yang D, Gold B. Origin of mutations in genes associated with human glioblastoma multiform cancer: random polymerase errors versus deamination. Heliyon 2019; 5:e01265. [PMID: 30899826 PMCID: PMC6407082 DOI: 10.1016/j.heliyon.2019.e01265] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 01/09/2019] [Accepted: 02/19/2019] [Indexed: 11/26/2022] Open
Abstract
The etiology of glioblastoma multiforme (GBM), the most serious form of brain cancer, remains obscure, although it has been proposed that cancer risk is a function of random polymerase errors that occur during stem cell division and the resulting mutations in oncogenes and tumor suppressor genes. Analysis of the 8 genes (PTEN, TP53, EGFR, PIK3R1, PIK3CA, NF1, RB1, IDH1) that are mutated in at least 5% of GBM tumors indicates a non-random mutation pattern that reflects a significant role for hydrolytic deamination at CpG sites. The formation of activating mutations in some genes, e.g., IDH1, where a very limited set of mutations are oncogenic, statistically cannot involve random mutagenesis due to polymerase errors that occur during each stem cell replication. Comparison of the in vitro misincorporation tendencies of three replicative polymerases and the “random” mutation pattern in a subset of genes indicates non-polymerase based pathways are involved. Analysis of the mutation patterns shows that chemical deamination that occurs at a slow rate at each CpG is favored over random polymerase errors by a factor of more than 10 million. Therefore, if a truncating nonsense mutation in a tumor suppressor, or an activating missense mutation in an oncogene, can occur due to a C > T base substitution at a CpG sequence, it is highly favored over other mutation pathways.
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Affiliation(s)
- Min Zhang
- Department of Pharmaceutical Sciences, University of Pittsburgh, 708 Salk Hall, 3501 Terrace Street, Pittsburgh PA 15261, USA
| | - Da Yang
- Department of Pharmaceutical Sciences, University of Pittsburgh, 708 Salk Hall, 3501 Terrace Street, Pittsburgh PA 15261, USA
| | - Barry Gold
- Department of Pharmaceutical Sciences, University of Pittsburgh, 708 Salk Hall, 3501 Terrace Street, Pittsburgh PA 15261, USA
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29
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Foley MC, Couto L, Rauf S, Boyke A. Insights into DNA polymerase δ’s mechanism for accurate DNA replication. J Mol Model 2019; 25:80. [DOI: 10.1007/s00894-019-3957-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 02/05/2019] [Indexed: 11/28/2022]
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30
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Eyal O, Berkenstadt M, Reznik-Wolf H, Poran H, Ziv-Baran T, Greenbaum L, Yonath H, Pras E. Prenatal diagnosis for de novo mutations: Experience from a tertiary center over a 10-year period. Mol Genet Genomic Med 2019; 7:e00573. [PMID: 30693677 PMCID: PMC6465671 DOI: 10.1002/mgg3.573] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 12/05/2018] [Accepted: 12/05/2018] [Indexed: 11/07/2022] Open
Abstract
Background This study summarizes the results of prenatal diagnosis due to a history of de novo mutation in a previous pregnancy, in a tertiary center in Israel, over a 10‐year period. Methods We sorted all cases of de novo mutations from a pool of 2,260 pregnancies for which prenatal molecular diagnosis was applied, between the years 2008 and 2017. We identified 122 molecular prenatal diagnosis performed for de novo mutations, in 90 women. Results While the total number of yearly prenatal diagnoses stayed stable, a linear increase was detected in the number of cases for which the procedure was done due to a previous de novo mutation: from 3 cases in 2008 to 24 cases in 2017. The most common diseases were Rett syndrome (19), neurofibromatosis Type‐1 (12) and Tuberous sclerosis (5). Recurrence occurred in 3 of the 90 women (3.3%) and hotspot mutations were identified in two genes accounting for 11 cases. We did not find a difference in paternal age at first occurrence of the de novo mutation between the study group and the control group. Conclusion The large increase in the annual number of prenatal diagnoses performed due to a previous pregnancy with a de novo mutation reflects the growing understanding regarding the role of these mutations in the pathogenesis of genetic diseases.
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Affiliation(s)
- Ori Eyal
- The Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Michal Berkenstadt
- The Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Haike Reznik-Wolf
- The Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Hana Poran
- The Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Tomer Ziv-Baran
- Sackler Faculty of Medicine, School of Public Health, Tel-Aviv University, Tel-Aviv, Israel
| | - Lior Greenbaum
- The Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.,The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - Hagit Yonath
- The Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Elon Pras
- The Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
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31
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Abe T, Branzei D, Hirota K. DNA Damage Tolerance Mechanisms Revealed from the Analysis of Immunoglobulin V Gene Diversification in Avian DT40 Cells. Genes (Basel) 2018; 9:genes9120614. [PMID: 30544644 PMCID: PMC6316486 DOI: 10.3390/genes9120614] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/26/2018] [Accepted: 11/30/2018] [Indexed: 01/19/2023] Open
Abstract
DNA replication is an essential biochemical reaction in dividing cells that frequently stalls at damaged sites. Homologous/homeologous recombination (HR)-mediated template switch and translesion DNA synthesis (TLS)-mediated bypass processes release arrested DNA replication forks. These mechanisms are pivotal for replication fork maintenance and play critical roles in DNA damage tolerance (DDT) and gap-filling. The avian DT40 B lymphocyte cell line provides an opportunity to examine HR-mediated template switch and TLS triggered by abasic sites by sequencing the constitutively diversifying immunoglobulin light-chain variable gene (IgV). During IgV diversification, activation-induced deaminase (AID) converts dC to dU, which in turn is excised by uracil DNA glycosylase and yields abasic sites within a defined window of around 500 base pairs. These abasic sites can induce gene conversion with a set of homeologous upstream pseudogenes via the HR-mediated template switch, resulting in templated mutagenesis, or can be bypassed directly by TLS, resulting in non-templated somatic hypermutation at dC/dG base pairs. In this review, we discuss recent works unveiling IgV diversification mechanisms in avian DT40 cells, which shed light on DDT mode usage in vertebrate cells and tolerance of abasic sites.
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Affiliation(s)
- Takuya Abe
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Minamiosawa 1-1, Hachioji-shi, Tokyo 192-0397, Japan.
- IFOM, the FIRC Institute of Molecular Oncology, Via Adamello 16, 20139 Milan, Italy.
| | - Dana Branzei
- IFOM, the FIRC Institute of Molecular Oncology, Via Adamello 16, 20139 Milan, Italy.
- Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche (IGM-CNR), Via Abbiategrasso 207, 27100 Pavia, Italy.
| | - Kouji Hirota
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Minamiosawa 1-1, Hachioji-shi, Tokyo 192-0397, Japan.
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32
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cAMP-mediated regulation of melanocyte genomic instability: A melanoma-preventive strategy. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2018; 115:247-295. [PMID: 30798934 DOI: 10.1016/bs.apcsb.2018.10.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Malignant melanoma of the skin is the leading cause of death from skin cancer and ranks fifth in cancer incidence among all cancers in the United States. While melanoma mortality has remained steady for the past several decades, melanoma incidence has been increasing, particularly among fair-skinned individuals. According to the American Cancer Society, nearly 10,000 people in the United States will die from melanoma this year. Individuals with dark skin complexion are protected damage generated by UV-light due to the high content of UV-blocking melanin pigment in their epidermis as well as better capacity for melanocytes to cope with UV damage. There is now ample evidence that suggests that the melanocortin 1 receptor (MC1R) is a major melanoma risk factor. Inherited loss-of-function mutations in MC1R are common in melanoma-prone persons, correlating with a less melanized skin complexion and poorer recovery from mutagenic photodamage. We and others are interested in the MC1R signaling pathway in melanocytes, its mechanisms of enhancing genomic stability and pharmacologic opportunities to reduce melanoma risk based on those insights. In this chapter, we review melanoma risk factors, the MC1R signaling pathway, and the relationship between MC1R signaling and DNA repair.
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33
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Raper AT, Reed AJ, Suo Z. Kinetic Mechanism of DNA Polymerases: Contributions of Conformational Dynamics and a Third Divalent Metal Ion. Chem Rev 2018; 118:6000-6025. [DOI: 10.1021/acs.chemrev.7b00685] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Austin T. Raper
- Department of Chemistry and Biochemistry, Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio 43210, United States
| | - Andrew J. Reed
- Department of Chemistry and Biochemistry, Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio 43210, United States
| | - Zucai Suo
- Department of Chemistry and Biochemistry, Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio 43210, United States
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34
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Haradhvala NJ, Kim J, Maruvka YE, Polak P, Rosebrock D, Livitz D, Hess JM, Leshchiner I, Kamburov A, Mouw KW, Lawrence MS, Getz G. Distinct mutational signatures characterize concurrent loss of polymerase proofreading and mismatch repair. Nat Commun 2018; 9:1746. [PMID: 29717118 PMCID: PMC5931517 DOI: 10.1038/s41467-018-04002-4] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 03/26/2018] [Indexed: 12/19/2022] Open
Abstract
Fidelity of DNA replication is maintained using polymerase proofreading and the mismatch repair pathway. Tumors with loss of function of either mechanism have elevated mutation rates with characteristic mutational signatures. Here we report that tumors with concurrent loss of both polymerase proofreading and mismatch repair function have mutational patterns that are not a simple sum of the signatures of the individual alterations, but correspond to distinct, previously unexplained signatures: COSMIC database signatures 14 and 20. We then demonstrate that in all five cases in which the chronological order of events could be determined, polymerase epsilon proofreading alterations precede the defect in mismatch repair. Overall, we illustrate that multiple distinct mutational signatures can result from different combinations of a smaller number of mutational processes (of either damage or repair), which can influence the interpretation and discovery of mutational signatures. Polymerase proofreading and the mismatch repair pathway maintain the fidelity of DNA replication. Here the authors show that tumors with concurrent loss of function of both pathways lead to mutation signatures that are not simply a sum of the signatures found in tumors involving single alteration.
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Affiliation(s)
- N J Haradhvala
- Department of Pathology and Cancer Center, Massachusetts General Hospital, 55 Fruit Street, Boston, MA, 02114, USA.,Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA, 02142, USA
| | - J Kim
- Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA, 02142, USA
| | - Y E Maruvka
- Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA, 02142, USA
| | - P Polak
- Department of Pathology and Cancer Center, Massachusetts General Hospital, 55 Fruit Street, Boston, MA, 02114, USA.,Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA, 02142, USA.,Harvard Medical School, 25 Shattuck Street, Boston, MA, 02115, USA
| | - D Rosebrock
- Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA, 02142, USA
| | - D Livitz
- Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA, 02142, USA
| | - J M Hess
- Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA, 02142, USA
| | - I Leshchiner
- Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA, 02142, USA
| | - A Kamburov
- Department of Pathology and Cancer Center, Massachusetts General Hospital, 55 Fruit Street, Boston, MA, 02114, USA.,Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA, 02142, USA.,Harvard Medical School, 25 Shattuck Street, Boston, MA, 02115, USA
| | - K W Mouw
- Harvard Medical School, 25 Shattuck Street, Boston, MA, 02115, USA.,Department of Radiation Oncology, Brigham and Women's Hospital, Dana-Farber Cancer Institute, 450 Brookline Ave, HIM 350, Boston, MA, 02215, USA
| | - M S Lawrence
- Department of Pathology and Cancer Center, Massachusetts General Hospital, 55 Fruit Street, Boston, MA, 02114, USA.,Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA, 02142, USA.,Harvard Medical School, 25 Shattuck Street, Boston, MA, 02115, USA
| | - G Getz
- Department of Pathology and Cancer Center, Massachusetts General Hospital, 55 Fruit Street, Boston, MA, 02114, USA. .,Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA, 02142, USA. .,Harvard Medical School, 25 Shattuck Street, Boston, MA, 02115, USA.
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35
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LA P, D B, Z D, J G, E M. Detection of Allelic Variants of the POLE and POLD1 Genes in Colorectal Cancer Patients. Balkan J Med Genet 2017; 20:83-88. [PMID: 29876237 PMCID: PMC5972507 DOI: 10.1515/bjmg-2017-0028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Incidence of colorectal cancer is high worldwide and it mostly occurs as an accumulation of environmental factors and genetic alterations. Hereditary colorectal cancer can develop as a part of a hereditary syndrome. There is a suspected correlation between colorectal cancer and allelic variants of the POLE and POLD1 genes. The aim of the present study was to look for associations between the allelic variants in the POLE and POLD1 genes and colorectal cancer. One thousand, seven hundred and forty-nine DNA samples from colorectal cancer patients were collected from 2002 to 2013. Samples were divided in three groups: hereditary colorectal cancer patients, patients with different hereditary cancer syndromes in their families and patients with no cancer history in their families. The DNA samples were screened for allelic variants of POLE rs483352909 and POLD1 rs39751463 using denaturing high performance liquid chromatography (DHPLC). All patients were negative for allelic variants rs483352909 of the POLE gene and rs397514632 of the POLD1 gene. One allelic variant rs373243003 in the POLE gene and one novel duplication of four nucleotides at the excision site between intron and exon (c.1384-5dupCCTA) in the POLD1 gene, was found. We could not detect or confirm the connection between the genetic variants in the POLD1 and POLE genes and colorectal cancer patients, but we detected a novel genetic variant with an unknown significance.
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Affiliation(s)
- Pätzold LA
- Institute of Oncology, Riga Stradiņš University, Riga, Latvia
| | - Bērziņa D
- Institute of Oncology, Riga Stradiņš University, Riga, Latvia
| | - Daneberga Z
- Institute of Oncology, Riga Stradiņš University, Riga, Latvia
| | - Gardovskis J
- Institute of Oncology, Riga Stradiņš University, Riga, Latvia
| | - Miklaševičs E
- Institute of Oncology, Riga Stradiņš University, Riga, Latvia
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36
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Masumura K, Toyoda-Hokaiwado N, Niimi N, Grúz P, Wada NA, Takeiri A, Jishage KI, Mishima M, Nohmi T. Limited ability of DNA polymerase kappa to suppress benzo[a]pyrene-induced genotoxicity in vivo. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2017; 58:644-653. [PMID: 29076178 DOI: 10.1002/em.22146] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 08/20/2017] [Accepted: 09/20/2017] [Indexed: 05/07/2023]
Abstract
DNA polymerase kappa (Polk) is a specialized DNA polymerase involved in translesion DNA synthesis. To understand the protective roles against genotoxins in vivo, we established inactivated Polk knock-in gpt delta (inactivated Polk KI) mice that possessed reporter genes for mutations and expressed inactive Polk. In this study, we examined genotoxicity of benzo[a]pyrene (BP) to determine whether Polk actually suppressed BP-induced genotoxicity as predicted by biochemistry and in vitro cell culture studies. Seven-week-old inactivated Polk KI and wild-type (WT) mice were treated with BP at doses of 5, 15, or 50 mg/(kg·day) for three consecutive days by intragastric gavage, and mutations in the colon and micronucleus formation in the peripheral blood were examined. Surprisingly, no differences were observed in the frequencies of mutations and micronucleus formation at 5 or 50 mg/kg doses. Inactivated Polk KI mice exhibited approximately two times higher gpt mutant frequency than did WT mice only at the 15 mg/kg dose. The frequency of micronucleus formation was slightly higher in inactivated Polk KI than in WT mice at the same dose, but it was statistically insignificant. The results suggest that Polk has a limited ability to suppress BP-induced genotoxicity in the colon and bone marrow and also that the roles of specialized DNA polymerases in mutagenesis and carcinogenesis should be examined not only by in vitro assays but also by in vivo mouse studies. We also report the spontaneous mutagenesis in inactivated Polk KI mice at young and old ages. Environ. Mol. Mutagen. 58:644-653, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Kenichi Masumura
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo, 158-8501, Japan
| | - Naomi Toyoda-Hokaiwado
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo, 158-8501, Japan
| | - Naoko Niimi
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo, 158-8501, Japan
| | - Petr Grúz
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo, 158-8501, Japan
| | - Naoko A Wada
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135 Komakado, Gotemba, Shizuoka, 412-8513, Japan
| | - Akira Takeiri
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135 Komakado, Gotemba, Shizuoka, 412-8513, Japan
| | - Kou-Ichi Jishage
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135 Komakado, Gotemba, Shizuoka, 412-8513, Japan
| | - Masayuki Mishima
- Research Division, Chugai Pharmaceutical Co., Ltd., 1-135 Komakado, Gotemba, Shizuoka, 412-8513, Japan
| | - Takehiko Nohmi
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo, 158-8501, Japan
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Baruch-Torres N, Brieba LG. Plant organellar DNA polymerases are replicative and translesion DNA synthesis polymerases. Nucleic Acids Res 2017; 45:10751-10763. [PMID: 28977655 PMCID: PMC5737093 DOI: 10.1093/nar/gkx744] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 08/14/2017] [Indexed: 02/01/2023] Open
Abstract
Genomes acquire lesions that can block the replication fork and some lesions must be bypassed to allow survival. The nuclear genome of flowering plants encodes two family-A DNA polymerases (DNAPs), the result of a duplication event, that are the sole DNAPs in plant organelles. These DNAPs, dubbed Plant Organellar Polymerases (POPs), resemble the Klenow fragment of bacterial DNAP I and are not related to metazoan and fungal mitochondrial DNAPs. Herein we report that replicative POPs from the plant model Arabidopsis thaliana (AtPolI) efficiently bypass one the most insidious DNA lesions, an apurinic/apyrimidinic (AP) site. AtPolIs accomplish lesion bypass with high catalytic efficiency during nucleotide insertion and extension. Lesion bypass depends on two unique polymerization domain insertions evolutionarily unrelated to the insertions responsible for lesion bypass by DNAP θ, an analogous lesion bypass polymerase. AtPolIs exhibit an insertion fidelity that ranks between the fidelity of replicative and lesion bypass DNAPs, moderate 3′-5′ exonuclease activity and strong strand-displacement. AtPolIs are the first known example of a family-A DNAP evolved to function in both DNA replication and lesion bypass. The lesion bypass capabilities of POPs may be required to prevent replication fork collapse in plant organelles.
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Affiliation(s)
- Noe Baruch-Torres
- Langebio-Cinvestav Sede Irapuato, Km. 9.6 Libramiento Norte Carretera. Irapuato-León, 36821 Irapuato Guanajuato, México
| | - Luis G Brieba
- Langebio-Cinvestav Sede Irapuato, Km. 9.6 Libramiento Norte Carretera. Irapuato-León, 36821 Irapuato Guanajuato, México
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38
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Ignatov A, Bondarenko K, Makarova A. Non-bulky Lesions in Human DNA: the Ways of Formation, Repair, and Replication. Acta Naturae 2017; 9:12-26. [PMID: 29104772 PMCID: PMC5662270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Indexed: 11/06/2022] Open
Abstract
DNA damage is a major cause of replication interruption, mutations, and cell death. DNA damage is removed by several types of repair processes. The involvement of specialized DNA polymerases in replication provides an important mechanism that helps tolerate persistent DNA damage. Specialized DNA polymerases incorporate nucleotides opposite lesions with high efficiency but demonstrate low accuracy of DNA synthesis. In this review, we summarize the types and mechanisms of formation and repair of non-bulky DNA lesions, and we provide an overview of the role of specialized DNA polymerases in translesion DNA synthesis.
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Affiliation(s)
- A.V. Ignatov
- Institute of Molecular Genetics of Russian Academy of Sciences, Kurchatov sq. 2, Moscow, 123182 , Russia
- Department of Molecular Biology, Faculty of Biology, Moscow State University, Leninskie Gory 1, bldg. 12, Moscow, 119991, Russia
| | - K.A. Bondarenko
- Institute of Molecular Genetics of Russian Academy of Sciences, Kurchatov sq. 2, Moscow, 123182 , Russia
| | - A.V. Makarova
- Institute of Molecular Genetics of Russian Academy of Sciences, Kurchatov sq. 2, Moscow, 123182 , Russia
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Abstract
Life as we know it, simply would not exist without DNA replication. All living organisms utilize a complex machinery to duplicate their genomes and the central role in this machinery belongs to replicative DNA polymerases, enzymes that are specifically designed to copy DNA. "Hassle-free" DNA duplication exists only in an ideal world, while in real life, it is constantly threatened by a myriad of diverse challenges. Among the most pressing obstacles that replicative polymerases often cannot overcome by themselves are lesions that distort the structure of DNA. Despite elaborate systems that cells utilize to cleanse their genomes of damaged DNA, repair is often incomplete. The persistence of DNA lesions obstructing the cellular replicases can have deleterious consequences. One of the mechanisms allowing cells to complete replication is "Translesion DNA Synthesis (TLS)". TLS is intrinsically error-prone, but apparently, the potential downside of increased mutagenesis is a healthier outcome for the cell than incomplete replication. Although most of the currently identified eukaryotic DNA polymerases have been implicated in TLS, the best characterized are those belonging to the "Y-family" of DNA polymerases (pols η, ι, κ and Rev1), which are thought to play major roles in the TLS of persisting DNA lesions in coordination with the B-family polymerase, pol ζ. In this review, we summarize the unique features of these DNA polymerases by mainly focusing on their biochemical and structural characteristics, as well as potential protein-protein interactions with other critical factors affecting TLS regulation.
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Affiliation(s)
- Alexandra Vaisman
- a Laboratory of Genomic Integrity , National Institute of Child Health and Human Development, National Institutes of Health , Bethesda , MD , USA
| | - Roger Woodgate
- a Laboratory of Genomic Integrity , National Institute of Child Health and Human Development, National Institutes of Health , Bethesda , MD , USA
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Normally lethal amino acid substitutions suppress an ultramutator DNA Polymerase δ variant. Sci Rep 2017; 7:46535. [PMID: 28417960 PMCID: PMC5394481 DOI: 10.1038/srep46535] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 03/22/2017] [Indexed: 02/06/2023] Open
Abstract
In yeast, the pol3-01,L612M double mutant allele, which causes defects in DNA polymerase delta (Pol δ) proofreading (pol3-01) and nucleotide selectivity (pol3-L612M), confers an “ultramutator” phenotype that rapidly drives extinction of haploid and diploid MMR-proficient cells. Here, we investigate antimutator mutations that encode amino acid substitutions in Pol δ that suppress this lethal phenotype. We find that most of the antimutator mutations individually suppress the pol3-01 and pol3-L612M mutator phenotypes. The locations of many of the amino acid substitutions in Pol δ resemble those of previously identified antimutator substitutions; however, two novel mutations encode substitutions (R674G and Q697R) of amino acids in the fingers domain that coordinate the incoming dNTP. These mutations are lethal without pol3-L612M and markedly change the mutation spectra produced by the pol3-01,L612M mutator allele, suggesting that they alter nucleotide selection to offset the pol3-L612M mutator phenotype. Consistent with this hypothesis, mutations and drug treatments that perturb dNTP pool levels disproportionately influence the viability of pol3-L612M,R674G and pol3-L612M,Q697R cells. Taken together, our findings suggest that mutation rate can evolve through genetic changes that alter the balance of dNTP binding and dissociation from DNA polymerases.
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41
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Acuna-Hidalgo R, Veltman JA, Hoischen A. New insights into the generation and role of de novo mutations in health and disease. Genome Biol 2016; 17:241. [PMID: 27894357 PMCID: PMC5125044 DOI: 10.1186/s13059-016-1110-1] [Citation(s) in RCA: 266] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Aside from inheriting half of the genome of each of our parents, we are born with a small number of novel mutations that occurred during gametogenesis and postzygotically. Recent genome and exome sequencing studies of parent-offspring trios have provided the first insights into the number and distribution of these de novo mutations in health and disease, pointing to risk factors that increase their number in the offspring. De novo mutations have been shown to be a major cause of severe early-onset genetic disorders such as intellectual disability, autism spectrum disorder, and other developmental diseases. In fact, the occurrence of novel mutations in each generation explains why these reproductively lethal disorders continue to occur in our population. Recent studies have also shown that de novo mutations are predominantly of paternal origin and that their number increases with advanced paternal age. Here, we review the recent literature on de novo mutations, covering their detection, biological characterization, and medical impact.
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Affiliation(s)
- Rocio Acuna-Hidalgo
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Joris A Veltman
- Department of Human Genetics, Donders Institute of Neuroscience, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands.
- Department of Clinical Genetics, GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.
| | - Alexander Hoischen
- Department of Human Genetics, Donders Institute of Neuroscience, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
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42
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Hedglin M, Pandey B, Benkovic SJ. Characterization of human translesion DNA synthesis across a UV-induced DNA lesion. eLife 2016; 5. [PMID: 27770570 PMCID: PMC5123862 DOI: 10.7554/elife.19788] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 10/21/2016] [Indexed: 12/11/2022] Open
Abstract
Translesion DNA synthesis (TLS) during S-phase uses specialized TLS DNA polymerases to replicate a DNA lesion, allowing stringent DNA synthesis to resume beyond the offending damage. Human TLS involves the conjugation of ubiquitin to PCNA clamps encircling damaged DNA and the role of this post-translational modification is under scrutiny. A widely-accepted model purports that ubiquitinated PCNA recruits TLS polymerases such as pol η to sites of DNA damage where they may also displace a blocked replicative polymerase. We provide extensive quantitative evidence that the binding of pol η to PCNA and the ensuing TLS are both independent of PCNA ubiquitination. Rather, the unique properties of pols η and δ are attuned to promote an efficient and passive exchange of polymerases during TLS on the lagging strand. DOI:http://dx.doi.org/10.7554/eLife.19788.001
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Affiliation(s)
- Mark Hedglin
- Department of Chemistry, The Pennsylvania State University, University Park, United States
| | - Binod Pandey
- Department of Chemistry, The Pennsylvania State University, University Park, United States
| | - Stephen J Benkovic
- Department of Chemistry, The Pennsylvania State University, University Park, United States
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Sensitivity of human cells expressing low-fidelity or weak-catalytic-activity variants of DNA polymerase ζ to genotoxic stresses. DNA Repair (Amst) 2016; 45:34-43. [DOI: 10.1016/j.dnarep.2016.06.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 05/13/2016] [Accepted: 06/04/2016] [Indexed: 01/22/2023]
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Y-family DNA polymerase-independent gap-filling translesion synthesis across aristolochic acid-derived adenine adducts in mouse cells. DNA Repair (Amst) 2016; 46:55-60. [PMID: 27497692 DOI: 10.1016/j.dnarep.2016.07.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 07/25/2016] [Accepted: 07/27/2016] [Indexed: 12/16/2022]
Abstract
Translesion DNA synthesis (TLS) operates when replicative polymerases are blocked by DNA lesions. To investigate the mechanism of mammalian TLS, we employed a plasmid bearing a single 7-(deoxyadenosine-N6-yl)-aristolactam I (dA-AL-I) adduct, which is generated by the human carcinogen, aristolochic acid I, and genetically engineered mouse embryonic fibroblasts. This lesion induces A to T transversions at a high frequency. The simultaneous knockouts of the Polh, Poli and Polk genes did not influence the TLS efficiency or the coding property of dA-AL-I, indicating that an unknown DNA polymerase(s) can efficiently catalyze the insertion of a nucleotide opposite the adduct and subsequent extension. Similarly, knockout of the Rev1 gene did not significantly affect TLS. However, knockout of the Rev3l gene, coding for the catalytic subunit of polζ, drastically suppressed TLS and abolished dA-AL-I to T transversions. The results support the idea that Rev1 is not essential for the cellular TLS functions of polζ in mammalian cells. Furthermore, the frequency of dA-AL-I to T transversion was affected by a sequence context, suggesting that TLS, at least in part, contributes to the formation of mutational hot and cold spots observed in aristolochic acid-induced cancers.
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45
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Nicolas E, Golemis EA, Arora S. POLD1: Central mediator of DNA replication and repair, and implication in cancer and other pathologies. Gene 2016; 590:128-41. [PMID: 27320729 PMCID: PMC4969162 DOI: 10.1016/j.gene.2016.06.031] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 06/10/2016] [Accepted: 06/14/2016] [Indexed: 02/06/2023]
Abstract
The evolutionarily conserved human polymerase delta (POLD1) gene encodes the large p125 subunit which provides the essential catalytic activities of polymerase δ (Polδ), mediated by 5′–3′ DNA polymerase and 3′–5′ exonuclease moieties. POLD1 associates with three smaller subunits (POLD2, POLD3, POLD4), which together with Replication Factor C and Proliferating Nuclear Cell Antigen constitute the polymerase holoenzyme. Polδ function is essential for replication, with a primary role as the replicase for the lagging strand. Polδ also has an important proofreading ability conferred by the exonuclease activity, which is critical for ensuring replicative fidelity, but also serves to repair DNA lesions arising as a result of exposure to mutagens. Polδ has been shown to be important for multiple forms of DNA repair, including nucleotide excision repair, double strand break repair, base excision repair, and mismatch repair. A growing number of studies in the past decade have linked germline and sporadic mutations in POLD1 and the other subunits of Polδ with human pathologies. Mutations in Polδ in mice and humans lead to genomic instability, mutator phenotype and tumorigenesis. The advent of genome sequencing techniques has identified damaging mutations in the proofreading domain of POLD1 as the underlying cause of some inherited cancers, and suggested that mutations in POLD1 may influence therapeutic management. In addition, mutations in POLD1 have been identified in the developmental disorders of mandibular hypoplasia, deafness, progeroid features and lipodystrophy and atypical Werner syndrome, while changes in expression or activity of POLD1 have been linked to senescence and aging. Intriguingly, some recent evidence suggests that POLD1 function may also be altered in diabetes. We provide an overview of critical Polδ activities in the context of these pathologic conditions.
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Affiliation(s)
- Emmanuelle Nicolas
- Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | - Erica A Golemis
- Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | - Sanjeevani Arora
- Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
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46
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Hirota K, Tsuda M, Mohiuddin, Tsurimoto T, Cohen IS, Livneh Z, Kobayashi K, Narita T, Nishihara K, Murai J, Iwai S, Guilbaud G, Sale JE, Takeda S. In vivo evidence for translesion synthesis by the replicative DNA polymerase δ. Nucleic Acids Res 2016; 44:7242-50. [PMID: 27185888 PMCID: PMC5009730 DOI: 10.1093/nar/gkw439] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 05/06/2016] [Indexed: 12/17/2022] Open
Abstract
The intolerance of DNA polymerase δ (Polδ) to incorrect base pairing contributes to its extremely high accuracy during replication, but is believed to inhibit translesion synthesis (TLS). However, chicken DT40 cells lacking the POLD3 subunit of Polδ are deficient in TLS. Previous genetic and biochemical analysis showed that POLD3 may promote lesion bypass by Polδ itself independently of the translesion polymerase Polζ of which POLD3 is also a subunit. To test this hypothesis, we have inactivated Polδ proofreading in pold3 cells. This significantly restored TLS in pold3 mutants, enhancing dA incorporation opposite abasic sites. Purified proofreading-deficient human Polδ holoenzyme performs TLS of abasic sites in vitro much more efficiently than the wild type enzyme, with over 90% of TLS events resulting in dA incorporation. Furthermore, proofreading deficiency enhances the capability of Polδ to continue DNA synthesis over UV lesions both in vivo and in vitro. These data support Polδ contributing to TLS in vivo and suggest that the mutagenesis resulting from loss of Polδ proofreading activity may in part be explained by enhanced lesion bypass.
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Affiliation(s)
- Kouji Hirota
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshidakonoe, Sakyo-ku, Kyoto 606-8501, Japan Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Minami-Osawa 1-1, Hachioji- shi, Tokyo 192-0397, Japan
| | - Masataka Tsuda
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshidakonoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Mohiuddin
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshidakonoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Toshiki Tsurimoto
- Department of Biology, School of Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
| | - Isadora S Cohen
- Weizmann Institute of Science, Department of Biological Chemistry, Rehovot 76100, Israel
| | - Zvi Livneh
- Weizmann Institute of Science, Department of Biological Chemistry, Rehovot 76100, Israel
| | - Kaori Kobayashi
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Minami-Osawa 1-1, Hachioji- shi, Tokyo 192-0397, Japan
| | - Takeo Narita
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshidakonoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kana Nishihara
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshidakonoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Junko Murai
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshidakonoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Shigenori Iwai
- Division of Chemistry, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan
| | - Guillaume Guilbaud
- Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Julian E Sale
- Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Shunichi Takeda
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshidakonoe, Sakyo-ku, Kyoto 606-8501, Japan
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47
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Stability of the human polymerase δ holoenzyme and its implications in lagging strand DNA synthesis. Proc Natl Acad Sci U S A 2016; 113:E1777-86. [PMID: 26976599 DOI: 10.1073/pnas.1523653113] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In eukaryotes, DNA polymerase δ (pol δ) is responsible for replicating the lagging strand template and anchors to the proliferating cell nuclear antigen (PCNA) sliding clamp to form a holoenzyme. The stability of this complex is integral to every aspect of lagging strand replication. Most of our understanding comes from Saccharomyces cerevisae where the extreme stability of the pol δ holoenzyme ensures that every nucleobase within an Okazaki fragment is faithfully duplicated before dissociation but also necessitates an active displacement mechanism for polymerase recycling and exchange. However, the stability of the human pol δ holoenzyme is unknown. We designed unique kinetic assays to analyze the processivity and stability of the pol δ holoenzyme. Surprisingly, the results indicate that human pol δ maintains a loose association with PCNA while replicating DNA. Such behavior has profound implications on Okazaki fragment synthesis in humans as it limits the processivity of pol δ on undamaged DNA and promotes the rapid dissociation of pol δ from PCNA on stalling at a DNA lesion.
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48
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Yeom M, Kim IH, Kim JK, Kang K, Eoff RL, Guengerich FP, Choi JY. Effects of Twelve Germline Missense Variations on DNA Lesion and G-Quadruplex Bypass Activities of Human DNA Polymerase REV1. Chem Res Toxicol 2016; 29:367-79. [PMID: 26914252 DOI: 10.1021/acs.chemrestox.5b00513] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The Y-family DNA polymerase REV1 is involved in replicative bypass of damaged DNA and G-quadruplex (G4) DNA. In addition to a scaffolding role in the replicative bypass, REV1 acts in a catalytic role as a deoxycytidyl transferase opposite some replication stall sites, e.g., apurinic/apyrimidinic (AP) sites, N(2)-guanyl lesions, and G4 sites. We characterized the biochemical properties of 12 reported germline missense variants of human REV1, including the N373S variant associated with high risk of cervical cancer, using the recombinant REV1 (residues 330-833) proteins and DNA templates containing a G, AP site, N(2)-CH2(2-naphthyl)G (N(2)-NaphG), or G4. In steady-state kinetic analyses, the F427L, R434Q, M656V, D700N, R704Q, and P831L variants displayed 2- to 8-fold decreases in kcat/Km for dCTP insertion opposite all four templates, compared to that of wild-type, while the N373S, M407L, and N497S showed 2- to 3-fold increases with all four and the former three or two templates, respectively. The F427L, R434Q, M656V, and R704Q variants also had 2- to 3-fold lower binding affinities to DNA substrates containing G, an AP site, and/or N(2)-NaphG than wild-type. Distinctively, the N373S variant had a 3-fold higher binding affinity to G4 DNA than the wild-type, as well as a 2-fold higher catalytic activity opposite the first tetrad G, suggesting a facilitating effect of this variation on replication of G4 DNA sequences in certain human papillomavirus genomes. Our results suggest that the catalytic function of REV1 is moderately or slightly altered by at least nine genetic variations, and the G4 DNA processing function of REV1 is slightly enhanced by the N373S variation, which might provide the possibility that certain germline missense REV1 variations affect the individual susceptibility to carcinogenesis by modifying the capability of REV1 for replicative bypass past DNA lesions and G4 motifs derived from chemical and viral carcinogens.
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Affiliation(s)
| | | | | | | | - Robert L Eoff
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences , Little Rock, Arkansas 72205-7199, United States
| | - F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine , Nashville, Tennessee 37232-0146, United States
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McConechy MK, Talhouk A, Leung S, Chiu D, Yang W, Senz J, Reha-Krantz LJ, Lee CH, Huntsman DG, Gilks CB, McAlpine JN. Endometrial Carcinomas with POLE Exonuclease Domain Mutations Have a Favorable Prognosis. Clin Cancer Res 2016; 22:2865-73. [DOI: 10.1158/1078-0432.ccr-15-2233] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Accepted: 12/04/2015] [Indexed: 11/16/2022]
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50
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Lujan SA, Williams JS, Kunkel TA. Eukaryotic genome instability in light of asymmetric DNA replication. Crit Rev Biochem Mol Biol 2015; 51:43-52. [PMID: 26822554 DOI: 10.3109/10409238.2015.1117055] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The eukaryotic nuclear genome is replicated asymmetrically, with the leading strand replicated continuously and the lagging strand replicated as discontinuous Okazaki fragments that are subsequently joined. Both strands are replicated with high fidelity, but the processes used to achieve high fidelity are likely to differ. Here we review recent studies of similarities and differences in the fidelity with which the three major eukaryotic replicases, DNA polymerases α, δ, and ɛ, replicate the leading and lagging strands with high nucleotide selectivity and efficient proofreading. We then relate the asymmetric fidelity at the replication fork to the efficiency of DNA mismatch repair, ribonucleotide excision repair and topoisomerase 1 activity.
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Affiliation(s)
- Scott A Lujan
- a Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences , Research Triangle Park , NC , USA
| | - Jessica S Williams
- a Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences , Research Triangle Park , NC , USA
| | - Thomas A Kunkel
- a Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences , Research Triangle Park , NC , USA
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