1
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Kruchinin AA, Kamzeeva PN, Zharkov DO, Aralov AV, Makarova AV. 8-Oxoadenine: A «New» Player of the Oxidative Stress in Mammals? Int J Mol Sci 2024; 25:1342. [PMID: 38279342 PMCID: PMC10816367 DOI: 10.3390/ijms25021342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/13/2024] [Accepted: 01/15/2024] [Indexed: 01/28/2024] Open
Abstract
Numerous studies have shown that oxidative modifications of guanine (7,8-dihydro-8-oxoguanine, 8-oxoG) can affect cellular functions. 7,8-Dihydro-8-oxoadenine (8-oxoA) is another abundant paradigmatic ambiguous nucleobase but findings reported on the mutagenicity of 8-oxoA in bacterial and eukaryotic cells are incomplete and contradictory. Although several genotoxic studies have demonstrated the mutagenic potential of 8-oxoA in eukaryotic cells, very little biochemical and bioinformatics data about the mechanism of 8-oxoA-induced mutagenesis are available. In this review, we discuss dual coding properties of 8-oxoA, summarize historical and recent genotoxicity and biochemical studies, and address the main protective cellular mechanisms of response to 8-oxoA. We also discuss the available structural data for 8-oxoA bypass by different DNA polymerases as well as the mechanisms of 8-oxoA recognition by DNA repair enzymes.
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Affiliation(s)
- Alexander A. Kruchinin
- Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilova St., 119334 Moscow, Russia; (A.A.K.); (P.N.K.)
- National Research Center, Kurchatov Institute, Kurchatov sq. 2, 123182 Moscow, Russia
| | - Polina N. Kamzeeva
- Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilova St., 119334 Moscow, Russia; (A.A.K.); (P.N.K.)
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow, Russia;
| | - Dmitry O. Zharkov
- Department of Natural Sciences, Novosibirsk State University, 1 Pirogova St., 630090 Novosibirsk, Russia;
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia
| | - Andrey V. Aralov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow, Russia;
| | - Alena V. Makarova
- Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilova St., 119334 Moscow, Russia; (A.A.K.); (P.N.K.)
- National Research Center, Kurchatov Institute, Kurchatov sq. 2, 123182 Moscow, Russia
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2
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Yudkina AV, Endutkin AV, Diatlova EA, Zharkov DO. A non-canonical nucleotide from viral genomes interferes with the oxidative DNA damage repair system. DNA Repair (Amst) 2024; 133:103605. [PMID: 38042029 DOI: 10.1016/j.dnarep.2023.103605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 09/09/2023] [Accepted: 11/15/2023] [Indexed: 12/04/2023]
Abstract
Oxidative damage is a major source of genomic instability in all organisms with the aerobic metabolism. 8-Oxoguanine (8-oxoG), an abundant oxidized purine, is mutagenic and must be controlled by a dedicated DNA repair system (GO system) that prevents G:C→T:A transversions through an easily formed 8-oxoG:A mispair. In some forms, the GO system is present in nearly all cellular organisms. However, recent studies uncovered many instances of viruses possessing non-canonical nucleotides in their genomes. The features of genome damage and maintenance in such cases of alternative genetic chemistry remain barely explored. In particular, 2,6-diaminopurine (Z nucleotide) completely substitutes for A in the genomes of some bacteriophages, which have evolved pathways for dZTP synthesis and specialized polymerases that prefer dZTP over dATP. Here we address the ability of the GO system enzymes to cope with oxidative DNA damage in the presence of Z in DNA. DNA polymerases of two different structural families (Klenow fragment and RB69 polymerase) were able to incorporate dZMP opposite to 8-oxoG in the template, as well as 8-oxodGMP opposite to Z in the template. Fpg, a 8-oxoguanine-DNA glycosylase that discriminates against 8-oxoG:A mispairs, also did not remove 8-oxoG from 8-oxoG:Z mispairs. However, MutY, a DNA glycosylase that excises A from pairs with 8-oxoG, had a significantly lower activity on Z:8-oxoG mispairs. Similar preferences were observed for Fpg and MutY from different bacterial species (Escherichia coli, Staphylococcus aureus and Lactococcus lactis). Overall, the relaxed control of 8-oxoG in the presence of the Z nucleotide may be a source of additional mutagenesis in the genomes of bacteriophages or bacteria that have survived the viral invasion.
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Affiliation(s)
- Anna V Yudkina
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia; Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia
| | - Anton V Endutkin
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia
| | - Evgeniia A Diatlova
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia
| | - Dmitry O Zharkov
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia; Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia.
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3
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Kim DV, Diatlova EA, Zharkov TD, Melentyev VS, Yudkina AV, Endutkin AV, Zharkov DO. Back-Up Base Excision DNA Repair in Human Cells Deficient in the Major AP Endonuclease, APE1. Int J Mol Sci 2023; 25:64. [PMID: 38203235 PMCID: PMC10778768 DOI: 10.3390/ijms25010064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/15/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024] Open
Abstract
Apurinic/apyrimidinic (AP) sites are abundant DNA lesions generated both by spontaneous base loss and as intermediates of base excision DNA repair. In human cells, they are normally repaired by an essential AP endonuclease, APE1, encoded by the APEX1 gene. Other enzymes can cleave AP sites by either hydrolysis or β-elimination in vitro, but it is not clear whether they provide the second line of defense in living cells. Here, we studied AP site repairs in APEX1 knockout derivatives of HEK293FT cells using a reporter system based on transcriptional mutagenesis in the enhanced green fluorescent protein gene. Despite an apparent lack of AP site-processing activity in vitro, the cells efficiently repaired the tetrahydrofuran AP site analog resistant to β-elimination. This ability persisted even when the second AP endonuclease homolog, APE2, was also knocked out. Moreover, APEX1 null cells were able to repair uracil, a DNA lesion that is removed via the formation of an AP site. If AP site hydrolysis was chemically blocked, the uracil repair required the presence of NTHL1, an enzyme that catalyzes β-elimination. Our results suggest that human cells possess at least two back-up AP site repair pathways, one of which is NTHL1-dependent.
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Affiliation(s)
- Daria V. Kim
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (D.V.K.); (E.A.D.); (T.D.Z.); (V.S.M.); (A.V.Y.); (A.V.E.)
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
| | - Evgeniia A. Diatlova
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (D.V.K.); (E.A.D.); (T.D.Z.); (V.S.M.); (A.V.Y.); (A.V.E.)
| | - Timofey D. Zharkov
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (D.V.K.); (E.A.D.); (T.D.Z.); (V.S.M.); (A.V.Y.); (A.V.E.)
| | - Vasily S. Melentyev
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (D.V.K.); (E.A.D.); (T.D.Z.); (V.S.M.); (A.V.Y.); (A.V.E.)
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
| | - Anna V. Yudkina
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (D.V.K.); (E.A.D.); (T.D.Z.); (V.S.M.); (A.V.Y.); (A.V.E.)
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
| | - Anton V. Endutkin
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (D.V.K.); (E.A.D.); (T.D.Z.); (V.S.M.); (A.V.Y.); (A.V.E.)
| | - Dmitry O. Zharkov
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (D.V.K.); (E.A.D.); (T.D.Z.); (V.S.M.); (A.V.Y.); (A.V.E.)
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
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Eroshenko DA, Diatlova EA, Golyshev VM, Endutkin AV, Zharkov DO. Aberrant Repair of 8-Oxoguanine in Short DNA Bulges. DOKL BIOCHEM BIOPHYS 2023; 513:S82-S86. [PMID: 38337103 DOI: 10.1134/s1607672923600355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 11/25/2023] [Accepted: 11/25/2023] [Indexed: 02/12/2024]
Abstract
The presence of DNA damage can increase the likelihood of DNA replication errors and promote mutations. In particular, pauses of DNA polymerase at the site of damage can lead to polymerase slippage and the formation of 1-2-nucleotide bulges. Repair of such structures using an undamaged DNA template leads to small deletions. One of the most abundant oxidative DNA lesions, 8-oxoguanine (oxoG), was shown to induce small deletions, but the mechanism of this phenomenon is currently unknown. We studied the aberrant repair of oxoG located in one- and two-nucleotide bulges by the Escherichia coli and human base excision repair systems. Our results indicate that the repair in such substrates can serve as a mechanism for fixing small deletions in bacteria but not in humans.
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Affiliation(s)
- D A Eroshenko
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
- Novosibirsk State University, Novosibirsk, Russia
| | - E A Diatlova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
| | - V M Golyshev
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
| | - A V Endutkin
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
| | - D O Zharkov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia.
- Novosibirsk State University, Novosibirsk, Russia.
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5
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Torres JR, Lescano López I, Ayala AM, Alvarez ME. The Arabidopsis DNA glycosylase MBD4L repairs the nuclear genome in vivo. Plant J 2023; 115:1633-1646. [PMID: 37278489 DOI: 10.1111/tpj.16344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 06/02/2023] [Indexed: 06/07/2023]
Abstract
DNA glycosylases remove mispaired or modified bases from DNA initiating the base excision repair (BER) pathway. The DNA glycosylase MBD4 (methyl-CpG-binding domain protein 4) has been functionally characterized in mammals, but not yet in plants, where it is called MBD4-like (MBD4L). Mammalian MBD4 and Arabidopsis recombinant MBD4L excise U and T mispaired with G, as well as 5-fluorouracil (5-FU) and 5-bromouracil (5-BrU) in vitro. Here, we investigate the ability of Arabidopsis MBD4L to remove some of these substrates from the nuclear genome in vivo in coordination with uracil DNA glycosylase (AtUNG). We found that mbd4l mutants are hypersensitive to 5-FU and 5-BrU, as they displayed smaller size, less root growth, and higher cell death than control plants in both media. Using comet assays, we determined BER-associated DNA fragmentation in isolated nuclei and observed reduced DNA breaks in mbd4l plants under both conditions, but particularly with 5-BrU. The use of ung and ung x mbd4l mutants in these assays indicated that both MBD4L and AtUNG trigger nuclear DNA fragmentation in response to 5-FU. Consistently, we here report the nuclear localization of AtUNG based on the expression of AtUNG-GFP/RFP constructs in transgenic plants. Interestingly, MBD4L and AtUNG are transcriptionally coordinated but display not completely overlapping functions. MBD4L-deficient plants showed reduced expression of BER genes and enhanced expression of DNA damage response (DDR) gene markers. Overall, our findings indicate that Arabidopsis MBD4L is critical for maintaining nuclear genome integrity and preventing cell death under genotoxic stress conditions.
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Affiliation(s)
- José Roberto Torres
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, X5000HUA, Argentina
| | - Ignacio Lescano López
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, X5000HUA, Argentina
| | - Ana María Ayala
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, X5000HUA, Argentina
| | - María Elena Alvarez
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, X5000HUA, Argentina
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Lirussi L, Nilsen HL. DNA Glycosylases Define the Outcome of Endogenous Base Modifications. Int J Mol Sci 2023; 24:10307. [PMID: 37373453 DOI: 10.3390/ijms241210307] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/13/2023] [Accepted: 06/16/2023] [Indexed: 06/29/2023] Open
Abstract
Chemically modified nucleic acid bases are sources of genomic instability and mutations but may also regulate gene expression as epigenetic or epitranscriptomic modifications. Depending on the cellular context, they can have vastly diverse impacts on cells, from mutagenesis or cytotoxicity to changing cell fate by regulating chromatin organisation and gene expression. Identical chemical modifications exerting different functions pose a challenge for the cell's DNA repair machinery, as it needs to accurately distinguish between epigenetic marks and DNA damage to ensure proper repair and maintenance of (epi)genomic integrity. The specificity and selectivity of the recognition of these modified bases relies on DNA glycosylases, which acts as DNA damage, or more correctly, as modified bases sensors for the base excision repair (BER) pathway. Here, we will illustrate this duality by summarizing the role of uracil-DNA glycosylases, with particular attention to SMUG1, in the regulation of the epigenetic landscape as active regulators of gene expression and chromatin remodelling. We will also describe how epigenetic marks, with a special focus on 5-hydroxymethyluracil, can affect the damage susceptibility of nucleic acids and conversely how DNA damage can induce changes in the epigenetic landscape by altering the pattern of DNA methylation and chromatin structure.
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Affiliation(s)
- Lisa Lirussi
- Department of Clinical Molecular Biology, Institute of Clinical Medicine, University of Oslo, 0318 Oslo, Norway
- Section of Clinical Molecular Biology (EpiGen), Akershus University Hospital, 1478 Lørenskog, Norway
- Department of Microbiology, Oslo University Hospital, 0424 Oslo, Norway
| | - Hilde Loge Nilsen
- Department of Clinical Molecular Biology, Institute of Clinical Medicine, University of Oslo, 0318 Oslo, Norway
- Department of Microbiology, Oslo University Hospital, 0424 Oslo, Norway
- Unit for Precision Medicine, Akershus University Hospital, 1478 Lørenskog, Norway
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Raja SJ, Van Houten B. UV-DDB as a General Sensor of DNA Damage in Chromatin: Multifaceted Approaches to Assess Its Direct Role in Base Excision Repair. Int J Mol Sci 2023; 24:10168. [PMID: 37373320 PMCID: PMC10298998 DOI: 10.3390/ijms241210168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
Base excision repair (BER) is a cellular process that removes damaged bases arising from exogenous and endogenous sources including reactive oxygen species, alkylation agents, and ionizing radiation. BER is mediated by the actions of multiple proteins which work in a highly concerted manner to resolve DNA damage efficiently to prevent toxic repair intermediates. During the initiation of BER, the damaged base is removed by one of 11 mammalian DNA glycosylases, resulting in abasic sites. Many DNA glycosylases are product-inhibited by binding to the abasic site more avidly than the damaged base. Traditionally, apurinic/apyrimidinic endonuclease 1, APE1, was believed to help turn over the glycosylases to undergo multiple rounds of damaged base removal. However, in a series of papers from our laboratory, we have demonstrated that UV-damaged DNA binding protein (UV-DDB) stimulates the glycosylase activities of human 8-oxoguanine glycosylase (OGG1), MUTY DNA glycosylase (MUTYH), alkyladenine glycosylase/N-methylpurine DNA glycosylase (AAG/MPG), and single-strand selective monofunctional glycosylase (SMUG1), between three- and five-fold. Moreover, we have shown that UV-DDB can assist chromatin decompaction, facilitating access of OGG1 to 8-oxoguanine damage in telomeres. This review summarizes the biochemistry, single-molecule, and cell biology approaches that our group used to directly demonstrate the essential role of UV-DDB in BER.
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Affiliation(s)
- Sripriya J. Raja
- Molecular Pharmacology Graduate Program, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA;
- UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Bennett Van Houten
- Molecular Pharmacology Graduate Program, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA;
- UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA
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Roszkowicz-Ostrowska K, Młotkowska P, Kowalczyk P, Marciniak E, Barszcz M, Misztal T. Central Stimulatory Effect of Kynurenic Acid on BDNF-TrkB Signaling and BER Enzymatic Activity in the Hippocampal CA1 Field in Sheep. Int J Mol Sci 2022; 24. [PMID: 36613581 DOI: 10.3390/ijms24010136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/12/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
Deficiency of neurotrophic factors and oxidative DNA damage are common causes of many neurodegenerative diseases. Recently, the importance of kynurenic acid (KYNA), an active metabolite of tryptophan, has increased as a neuroprotective molecule in the brain. Therefore, the present study tested the hypothesis that centrally acting KYNA would positively affect: (1) brain-derived neurotrophic factor (BDNF)-tyrosine receptor kinase B (TrkB) signaling and (2) selected base excision repair (BER) pathway enzymes activities in the hippocampal CA1 field in sheep. Both lower (20 μg in total) and higher (100 μg in total) doses of KYNA infused into the third brain ventricle differentially increased the abundance of BDNF and TrkB mRNA in the CA1 field; additionally, the higher dose increased BDNF tissue concentration. The lower dose of KYNA increased mRNA expression for 8-oxoguanine glycosylase (OGG1), N-methylpurine DNA glycosylase (MPG), and thymine DNA glycosylase and stimulated the repair of 1,N6-ethenodeoxyadenosine and 3,N4-ethenodeoxy-cytosine as determined by the excision efficiency of lesioned nucleobases. The higher dose increased the abundance of OGG1 and MPG transcripts, however, its stimulatory effect on repair activity was less pronounced in all cases compared to the lower dose. The increased level of AP-endonuclease mRNA expression was dose-dependent. In conclusion, the potential neurotrophic and neuroprotective effects of KYNA in brain cells may involve stimulation of the BDNF-TrkB and BER pathways.
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Cecchini NM, Torres JR, López IL, Cobo S, Nota F, Alvarez ME. Alternative splicing of an exitron determines the subnuclear localization of the Arabidopsis DNA glycosylase MBD4L under heat stress. Plant J 2022; 110:377-388. [PMID: 35061303 DOI: 10.1111/tpj.15675] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 01/15/2022] [Indexed: 06/14/2023]
Affiliation(s)
- Nicolás Miguel Cecchini
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, Argentina
| | - José Roberto Torres
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, Argentina
| | - Ignacio Lescano López
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, Argentina
| | - Santiago Cobo
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, Argentina
| | - Florencia Nota
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, Argentina
| | - María Elena Alvarez
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, Argentina
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10
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Zhdanova PV, Ishchenko AA, Chernonosov AA, Zharkov DO, Koval VV. Dataset for dynamics and conformational changes in human NEIL2 protein analyzed by integrative structural biology approach. Data Brief 2022; 40:107760. [PMID: 35005149 DOI: 10.1016/j.dib.2021.107760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/10/2021] [Accepted: 12/15/2021] [Indexed: 11/30/2022] Open
Abstract
This work presents new data on human endonuclease VIII-like 2 protein (hNEIL2), a part of DNA glycosylases of the helix–two-turn–helix structural superfamily. While X-ray structure of oNEIL2 (opossum Monodelphis) was resolved partially [1], the structure of hNEIL2 has not yet been determined. This data article describes a powerful combination of hydrogen-deuterium exchange mass spectrometry, homology modeling, and molecular dynamics simulations for protein conformational dynamics analysis. The data supplied in this work are related to the research article entitled “Dynamics and Conformational Changes in Human NEIL2 DNA Glycosylase Analyzed by Hydrogen/Deuterium Exchange Mass Spectrometry”.
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Key Words
- Base excision repair
- CD, circular dichroism
- DNA damage
- DNA glycosylases
- DNA repair
- DTT, (2S,3S)-1,4-Bis(sulfanyl)butane-2,3-diol
- ESI, electrospray ionization
- HDX-MS
- HDX-MS, hydrogen-deuterium exchange mass spectrometry
- HEPES, 2-[4-(2-Hydroxyethyl)piperazin-1-yl]ethane-1-sulfonic acid
- IPTG, Propan-2-yl 1-thio-β-D-galactopyranoside
- LB, Lysogeny broth
- LC-MS, liquid chromatography–mass spectrometry
- MD, molecular dynamics
- MDTRA, Molecular Dynamics Trajectory Reader & Analyzer
- Molecular dynamics
- NEIL2
- PDB, Protein Data Bank
- RMSD, root-mean-square deviation
- SDS-PAGE, sodium dodecyl sulphate–polyacrylamide gel electrophoresis
- Structural dynamics
- TCEP, 3,3’,3’’-Phosphanetriyltripropanoic acid
- hNEIL2, human endonuclease VIII-like 2 protein
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Zhang Y, Hu J, Yang XY, Zhang CY. Combination of bidirectional strand displacement amplification with single-molecule detection for multiplexed DNA glycosylases assay. Talanta 2021; 235:122805. [PMID: 34517663 DOI: 10.1016/j.talanta.2021.122805] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/30/2021] [Accepted: 08/13/2021] [Indexed: 11/21/2022]
Abstract
DNA glycosylases can initiate base excision repair pathway to repair endogenous DNA base damages for the maintenance of genome stability. Multiple DNA glycosylases exhibit abnormal in various diseases, and the simultaneous measurement of different DNA glycosylases is critical to clinical diagnosis and drug discovery. Herein, we take advantage of single-molecule detection and bidirectional strand displacement amplification (SDA) to simultaneously detect uracil DNA glycolase (UDG) and human alkyladenine DNA glycosylase (hAAG). We design a partial double-stranded DNA (dsDNA) substrate modified with specific recognition sites of UDG and hAAG. The dsDNA substrate is labeled with BHQ1 and BHQ2 at the 5'-ends and then hybridizes with the Cy3/Cy5-labeled reporter probes to obtain the BHQ1/Cy3 and BHQ2/Cy5 base pairs, resulting in the quenching of Cy3/Cy5 fluorescence by BHQ1/BHQ2 via fluorescence resonance energy transfer (FRET). When UDG and hAAG are present, they can induce the base excision repair reaction and subsequently initiate the bidirectional SDA amplification process, releasing the Cy5/Cy3-labeled reporter probes from the dsDNA substrate and consequently the recovery of Cy5 and Cy3 fluorescence, which can be measured by single-molecule detection, with Cy5 indicating UDG and Cy3 indicating hAAG. This method possesses high sensitivity and good selectivity with the capability of quantifying multiple DNA glycosylases at the single-cell level. Furthermore, it can be used to simultaneously screen DNA glycosylase inhibitors and determine enzyme kinetic parameters, with the potential of sensing various DNA/RNA enzymes by simple changing the recognition sites of DNA substrates.
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12
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de Sousa MML, Ye J, Luna L, Hildrestrand G, Bjørås K, Scheffler K, Bjørås M. Impact of Oxidative DNA Damage and the Role of DNA Glycosylases in Neurological Dysfunction. Int J Mol Sci 2021; 22:12924. [PMID: 34884729 PMCID: PMC8657561 DOI: 10.3390/ijms222312924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 11/25/2021] [Accepted: 11/27/2021] [Indexed: 11/16/2022] Open
Abstract
The human brain requires a high rate of oxygen consumption to perform intense metabolic activities, accounting for 20% of total body oxygen consumption. This high oxygen uptake results in the generation of free radicals, including reactive oxygen species (ROS), which, at physiological levels, are beneficial to the proper functioning of fundamental cellular processes. At supraphysiological levels, however, ROS and associated lesions cause detrimental effects in brain cells, commonly observed in several neurodegenerative disorders. In this review, we focus on the impact of oxidative DNA base lesions and the role of DNA glycosylase enzymes repairing these lesions on brain function and disease. Furthermore, we discuss the role of DNA base oxidation as an epigenetic mechanism involved in brain diseases, as well as potential roles of DNA glycosylases in different epigenetic contexts. We provide a detailed overview of the impact of DNA glycosylases on brain metabolism, cognition, inflammation, tissue loss and regeneration, and age-related neurodegenerative diseases based on evidence collected from animal and human models lacking these enzymes, as well as post-mortem studies on patients with neurological disorders.
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Affiliation(s)
- Mirta Mittelstedt Leal de Sousa
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, 7028 Trondheim, Norway; (J.Y.); (K.B.)
| | - Jing Ye
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, 7028 Trondheim, Norway; (J.Y.); (K.B.)
| | - Luisa Luna
- Department of Microbiology, Oslo University Hospital, University of Oslo, Rikshospitalet, 0424 Oslo, Norway; (L.L.); (G.H.)
| | - Gunn Hildrestrand
- Department of Microbiology, Oslo University Hospital, University of Oslo, Rikshospitalet, 0424 Oslo, Norway; (L.L.); (G.H.)
| | - Karine Bjørås
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, 7028 Trondheim, Norway; (J.Y.); (K.B.)
| | - Katja Scheffler
- Department of Neurology, St. Olavs Hospital, 7006 Trondheim, Norway;
- Department of Laboratory Medicine, St. Olavs Hospital, 7006 Trondheim, Norway
- Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | - Magnar Bjørås
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, 7028 Trondheim, Norway; (J.Y.); (K.B.)
- Department of Microbiology, Oslo University Hospital, University of Oslo, Rikshospitalet, 0424 Oslo, Norway; (L.L.); (G.H.)
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13
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Zhdanova PV, Ishchenko AA, Chernonosov AA, Zharkov DO, Koval VV. Dynamics and Conformational Changes in Human NEIL2 DNA Glycosylase Analyzed by Hydrogen/Deuterium Exchange Mass Spectrometry. J Mol Biol 2021; 434:167334. [PMID: 34757057 DOI: 10.1016/j.jmb.2021.167334] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/18/2021] [Accepted: 10/25/2021] [Indexed: 12/31/2022]
Abstract
Base excision DNA repair (BER) is necessary for removal of damaged nucleobases from the genome and their replacement with normal nucleobases. BER is initiated by DNA glycosylases, the enzymes that cleave the N-glycosidic bonds of damaged deoxynucleotides. Human endonuclease VIII-like protein 2 (hNEIL2), belonging to the helix-two-turn-helix structural superfamily of DNA glycosylases, is an enzyme uniquely specific for oxidized pyrimidines in non-canonical DNA substrates such as bubbles and loops. The structure of hNEIL2 has not been solved; its closest homologs with known structures are NEIL2 from opossum and from giant mimivirus. Here we analyze the conformational dynamics of free hNEIL2 using a combination of hydrogen/deuterium exchange mass spectrometry, homology modeling and molecular dynamics simulations. We show that a prominent feature of vertebrate NEIL2 - a large insert in its N-terminal domain absent from other DNA glycosylases - is unstructured in solution. It was suggested that helix-two-turn-helix DNA glycosylases undergo open-close transition upon DNA binding, with the large movement of their N- and C-terminal domains, but the open conformation has been elusive to capture. Our data point to the open conformation as favorable for free hNEIL2 in solution. Overall, our results are consistent with the view of hNEIL2 as a conformationally flexible protein, which may be due to its participation in the repair of non-canonical DNA structures and/or to the involvement in functional and regulatory protein-protein interactions.
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Affiliation(s)
- Polina V Zhdanova
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibisk, Russia; Novosibirsk State University, Novosibisk, Russia
| | - Alexander A Ishchenko
- Groupe "Réparation de lADN", Equipe Labellisée par la Ligue Nationale contre le Cancer, CNRS UMR 8200, Univ. Paris-Sud, Université Paris-Saclay, Villejuif F-94805, France; Gustave Roussy, Université Paris-Saclay, Villejuif F-94805, France
| | | | - Dmitry O Zharkov
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibisk, Russia; Novosibirsk State University, Novosibisk, Russia
| | - Vladimir V Koval
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibisk, Russia; Novosibirsk State University, Novosibisk, Russia.
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14
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Jiang T, Monari A, Dumont E, Bignon E. Molecular Mechanisms Associated with Clustered Lesion-Induced Impairment of 8-oxoG Recognition by the Human Glycosylase OGG1. Molecules 2021; 26:molecules26216465. [PMID: 34770874 PMCID: PMC8587150 DOI: 10.3390/molecules26216465] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/21/2021] [Accepted: 10/23/2021] [Indexed: 11/16/2022] Open
Abstract
The 8-oxo-7,8-dihydroguanine, referred to as 8-oxoG, is a highly mutagenic DNA lesion that can provoke the appearance of mismatches if it escapes the DNA Damage Response. The specific recognition of its structural signature by the hOGG1 glycosylase is the first step along the Base Excision Repair pathway, which ensures the integrity of the genome by preventing the emergence of mutations. 8-oxoG formation, structural features, and repair have been matters of extensive research; more recently, this active field of research expended to the more complicated case of 8-oxoG within clustered lesions. Indeed, the presence of a second lesion within 1 or 2 helix turns can dramatically impact the repair yields of 8-oxoG by glycosylases. In this work, we use μs-range molecular dynamics simulations and machine-learning-based postanalysis to explore the molecular mechanisms associated with the recognition of 8-oxoG by hOGG1 when embedded in a multiple-lesion site with a mismatch in 5′ or 3′. We delineate the stiffening of the DNA–protein interactions upon the presence of the mismatches, and rationalize the much lower repair yields reported with a 5′ mismatch by describing the perturbation of 8-oxoG structural features upon addition of an adjacent lesion.
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Affiliation(s)
- Tao Jiang
- Laboratoire de Chimie—UMR CNRS 5182, ENS de Lyon, Université de Lyon, 46 Allée d’Italie, F-69000 Lyon, France; (T.J.); (E.D.)
| | - Antonio Monari
- Laboratoire de Physique et Chimie Théoriques—UMR CNRS 7019, Faculté des Sciences et Technologies, Université de Lorraine, Boulevard des Aiguillettes, F-54506 Vandoeuvre-les-Nancy, France;
- Université de Paris and CNRS, ITODYS, F-75006 Paris, France
| | - Elise Dumont
- Laboratoire de Chimie—UMR CNRS 5182, ENS de Lyon, Université de Lyon, 46 Allée d’Italie, F-69000 Lyon, France; (T.J.); (E.D.)
- Institut Universitaire de France, 5 rue Descartes, F-75005 Paris, France
| | - Emmanuelle Bignon
- Laboratoire de Physique et Chimie Théoriques—UMR CNRS 7019, Faculté des Sciences et Technologies, Université de Lorraine, Boulevard des Aiguillettes, F-54506 Vandoeuvre-les-Nancy, France;
- Correspondence:
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15
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Wallace SS. Consequences and repair of radiation-induced DNA damage: fifty years of fun questions and answers. Int J Radiat Biol 2021; 98:367-382. [PMID: 34187282 DOI: 10.1080/09553002.2021.1948141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
PURPOSE To summarize succinctly the 50 years of research undertaken in my laboratory and to provide an overview of my career in science. It is certainly a privilege to have been asked by Carmel Mothersill and Penny Jeggo to contribute to this special issue of the International Journal of Radiation Biology focusing on the work of women in the radiation sciences. CONCLUSION My students, post-docs and I identified and characterized a number of the enzymes that recognize and remove radiation-damaged DNA bases, the DNA glycosylases, which are the first enzymes in the Base Excision Repair (BER) pathway. Although this pathway actually evolved to repair oxidative and other endogenous DNA damages, it is also responsible for removing the vast majority of radiation-induced DNA damages including base damages, alkali-labile lesions and single strand breaks. However, because of its high efficiency, attempted BER of clustered lesions produced by ionizing radiation, can have disastrous effects on cellular DNA. We also evaluated the potential biological consequences of many of the radiation-induced DNA lesions. In addition, with collaborators, we employed computational techniques, x-ray crystallography and single molecule approaches to answer many questions at the molecular level.
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Affiliation(s)
- Susan S Wallace
- Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, VT, USA
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16
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Prorok P, Grin IR, Matkarimov BT, Ishchenko AA, Laval J, Zharkov DO, Saparbaev M. Evolutionary Origins of DNA Repair Pathways: Role of Oxygen Catastrophe in the Emergence of DNA Glycosylases. Cells 2021; 10:1591. [PMID: 34202661 DOI: 10.3390/cells10071591] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/17/2021] [Accepted: 06/18/2021] [Indexed: 11/23/2022] Open
Abstract
It was proposed that the last universal common ancestor (LUCA) evolved under high temperatures in an oxygen-free environment, similar to those found in deep-sea vents and on volcanic slopes. Therefore, spontaneous DNA decay, such as base loss and cytosine deamination, was the major factor affecting LUCA’s genome integrity. Cosmic radiation due to Earth’s weak magnetic field and alkylating metabolic radicals added to these threats. Here, we propose that ancient forms of life had only two distinct repair mechanisms: versatile apurinic/apyrimidinic (AP) endonucleases to cope with both AP sites and deaminated residues, and enzymes catalyzing the direct reversal of UV and alkylation damage. The absence of uracil–DNA N-glycosylases in some Archaea, together with the presence of an AP endonuclease, which can cleave uracil-containing DNA, suggests that the AP endonuclease-initiated nucleotide incision repair (NIR) pathway evolved independently from DNA glycosylase-mediated base excision repair. NIR may be a relic that appeared in an early thermophilic ancestor to counteract spontaneous DNA damage. We hypothesize that a rise in the oxygen level in the Earth’s atmosphere ~2 Ga triggered the narrow specialization of AP endonucleases and DNA glycosylases to cope efficiently with a widened array of oxidative base damage and complex DNA lesions.
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17
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Endutkin AV, Panferova EP, Barmatov AE, Zharkov DO. DNA glycosylases for 8-oxoguanine repair in Staphylococcus aureus. DNA Repair (Amst) 2021; 105:103160. [PMID: 34192601 DOI: 10.1016/j.dnarep.2021.103160] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 11/20/2022]
Abstract
GO system is part of base excision DNA repair and is required for the correct repair of 8-oxoguanine (8-oxoG), one of the most abundant oxidative lesions. Due to the ability of 8-oxoG to mispair with A, this base is highly mutagenic, and its repair requires two enzymes: Fpg that removes 8-oxoG from 8-oxoG:C pairs, and MutY that excises the normal A from 8-oxoG:A mispairs. Here we characterize the properties of putative GO system DNA glycosylases from Staphylococcus aureus, an important human opportunistic pathogen that causes hospital infections and presents a serious health concern due to quick spread of antibiotic-resistant strains. In addition to Fpg and MutY from the reference NCTC 8325 strain (SauFpg1 and SauMutY), we have also studied an Fpg homolog from a multidrug-resistant C0673 isolate (SauFpg2), which is different from SauFpg1 in its sequence. Both SauFpg enzymes showed the highest activity at pH 7.0-9.0 and NaCl concentrations 25-75 mM (SauFpg1) or 50-100 mM (SauFpg2), whereas SauMutY was active at a broad pH range and had a salt optimum at ∼75 mM NaCl. Both SauFpg1 and SauFpg2 bound and cleaved duplexes containing 8-oxoG, 5-hydroxyuracil, 5,6-dihydrouracil or apurinic/apyrimidinic site paired with C, T, or G, but not with A. For SauFpg1 and SauFpg2, 8-oxoG was the best substrate tested, and 5,6-dihydrouracil was the worst one. SauMutY efficiently excised adenine from duplex substrates containing A:8-oxoG or A:G pairs. SauFpg enzymes were readily trapped on DNA by NaBH4 treatment, indicating formation of a Schiff base reaction intermediate. Surprisingly, SauMutY was also trapped significantly better than its E. coli homolog. All three S. aureus GO glycosylases drastically reduced spontaneous mutagenesis when expressed in an fpg mutY E. coli double mutant. Overall, we conclude that S. aureus possesses an active GO system, which could possibly be targeted for sensitization of this pathogen to oxidative stress.
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18
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Abstract
The GO system is part of the DNA base excision repair pathway and is required for the error-free repair of 8-oxoguanine (oxoG), one of the most common oxidative DNA lesions. Due to the ability of oxoG to form oxoG:A mispairs, this base is highly mutagenic. Its repair requires the action of two enzymes: 8-oxoguanine DNA glycosylase (Fpg or MutM in bacteria and OGG1 in eukaryotes), which removes oxoG from oxoG:C pairs, and adenine DNA glycosylase (MutY in bacteria and MUTYH in eukaryotes), which removes A from oxoG:A mispairs to prevent mutations. The third enzyme of the system (MutT in bacteria and MTH1 or NUDT1 in eukaryotes) hydrolyzes 8-oxo-2'-deoxyguanosine triphosphate, thus preventing its incorporation into DNA. Recent data point to the proteins of the GO system as promising targets for the therapy of cancer, autoimmune diseases, and bacterial infections. This review highlights the structure and specificity of the GO system in bacteria and eukaryotes and its unique role in mutation avoidance.
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Affiliation(s)
- A V Endutkin
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia.,
| | - D O Zharkov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia.,Novosibirsk State University, Novosibirsk, 630090 Russia.,
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19
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Bordin DL, Lirussi L, Nilsen H. Cellular response to endogenous DNA damage: DNA base modifications in gene expression regulation. DNA Repair (Amst) 2021; 99:103051. [PMID: 33540225 DOI: 10.1016/j.dnarep.2021.103051] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/15/2021] [Accepted: 01/18/2021] [Indexed: 12/19/2022]
Abstract
The integrity of the genetic information is continuously challenged by numerous genotoxic insults, most frequently in the form of oxidation, alkylation or deamination of the bases that result in DNA damage. These damages compromise the fidelity of the replication, and interfere with the progression and function of the transcription machineries. The DNA damage response (DDR) comprises a series of strategies to deal with DNA damage, including transient transcriptional inhibition, activation of DNA repair pathways and chromatin remodeling. Coordinated control of transcription and DNA repair is required to safeguardi cellular functions and identities. Here, we address the cellular responses to endogenous DNA damage, with a particular focus on the role of DNA glycosylases and the Base Excision Repair (BER) pathway, in conjunction with the DDR factors, in responding to DNA damage during the transcription process. We will also discuss functions of newly identified epigenetic and regulatory marks, such as 5-hydroxymethylcytosine and its oxidative products and 8-oxoguanine, that were previously considered only as DNA damages. In light of these resultsthe classical perception of DNA damage as detrimental for cellular processes are changing. and a picture emerges whereDNA glycosylases act as dynamic regulators of transcription, placing them at the intersection of DNA repair and gene expression modulation.
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Affiliation(s)
- Diana L Bordin
- Department of Clinical Molecular Biology, University of Oslo, 0318, Oslo, Norway; Department of Clinical Molecular Biology (EpiGen), Akershus University Hospital, 1478, Lørenskog, Norway
| | - Lisa Lirussi
- Department of Clinical Molecular Biology, University of Oslo, 0318, Oslo, Norway; Department of Clinical Molecular Biology (EpiGen), Akershus University Hospital, 1478, Lørenskog, Norway
| | - Hilde Nilsen
- Department of Clinical Molecular Biology, University of Oslo, 0318, Oslo, Norway; Department of Clinical Molecular Biology (EpiGen), Akershus University Hospital, 1478, Lørenskog, Norway.
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20
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Popov AV, Endutkin AV, Yatsenko DD, Yudkina AV, Barmatov AE, Makasheva KA, Raspopova DY, Diatlova EA, Zharkov DO. Molecular dynamics approach to identification of new OGG1 cancer-associated somatic variants with impaired activity. J Biol Chem 2021; 296:100229. [PMID: 33361155 PMCID: PMC7948927 DOI: 10.1074/jbc.ra120.014455] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 01/02/2023] Open
Abstract
DNA of living cells is always exposed to damaging factors. To counteract the consequences of DNA lesions, cells have evolved several DNA repair systems, among which base excision repair is one of the most important systems. Many currently used antitumor drugs act by damaging DNA, and DNA repair often interferes with chemotherapy and radiotherapy in cancer cells. Tumors are usually extremely genetically heterogeneous, often bearing mutations in DNA repair genes. Thus, knowledge of the functionality of cancer-related variants of proteins involved in DNA damage response and repair is of great interest for personalization of cancer therapy. Although computational methods to predict the variant functionality have attracted much attention, at present, they are mostly based on sequence conservation and make little use of modern capabilities in computational analysis of 3D protein structures. We have used molecular dynamics (MD) to model the structures of 20 clinically observed variants of a DNA repair enzyme, 8-oxoguanine DNA glycosylase. In parallel, we have experimentally characterized the activity, thermostability, and DNA binding in a subset of these mutant proteins. Among the analyzed variants of 8-oxoguanine DNA glycosylase, three (I145M, G202C, and V267M) were significantly functionally impaired and were successfully predicted by MD. Alone or in combination with sequence-based methods, MD may be an important functional prediction tool for cancer-related protein variants of unknown significance.
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Affiliation(s)
- Aleksandr V Popov
- Laboratory of Genome and Protein Engineering, SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia.
| | - Anton V Endutkin
- Laboratory of Genome and Protein Engineering, SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
| | - Darya D Yatsenko
- Laboratory of Genome and Protein Engineering, SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia; Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | - Anna V Yudkina
- Laboratory of Genome and Protein Engineering, SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
| | - Alexander E Barmatov
- Laboratory of Genome and Protein Engineering, SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
| | - Kristina A Makasheva
- Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | - Darya Yu Raspopova
- Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | - Evgeniia A Diatlova
- Laboratory of Genome and Protein Engineering, SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
| | - Dmitry O Zharkov
- Laboratory of Genome and Protein Engineering, SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia; Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia.
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Abstract
5-Methylcytosine (5mC) is an epigenetic mark known to contribute to the regulation of gene expression in a wide range of biological systems. Ten Eleven Translocation (TET) dioxygenases oxidize 5mC to 5-hydroxymethylcytosine, 5-formylcytosine, and 5-carboxylcytosine in metazoans and fungi. Moreover, two recent reports imply the existence of other species of modified cytosine in unicellular alga Chlamydomonas reinhardtii and malaria parasite Plasmodium falciparum. Here we provide an overview of the spectrum of cytosine modifications and their roles in demethylation of DNA and regulation of gene expression in different eukaryotic organisms.
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Affiliation(s)
- Maria Eleftheriou
- Division of Cancer and Stem Cells, School of Medicine, Biodiscovery Institute, University of Nottingham, University Park, UK
| | - Alexey Ruzov
- Division of Cancer and Stem Cells, School of Medicine, Biodiscovery Institute, University of Nottingham, University Park, UK.
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22
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Hans F, Senarisoy M, Bhaskar Naidu C, Timmins J. Focus on DNA Glycosylases-A Set of Tightly Regulated Enzymes with a High Potential as Anticancer Drug Targets. Int J Mol Sci 2020; 21:ijms21239226. [PMID: 33287345 PMCID: PMC7730500 DOI: 10.3390/ijms21239226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Accepted: 12/01/2020] [Indexed: 12/25/2022] Open
Abstract
Cancer is the second leading cause of death with tens of millions of people diagnosed with cancer every year around the world. Most radio- and chemotherapies aim to eliminate cancer cells, notably by causing severe damage to the DNA. However, efficient repair of such damage represents a common mechanism of resistance to initially effective cytotoxic agents. Thus, development of new generation anticancer drugs that target DNA repair pathways, and more particularly the base excision repair (BER) pathway that is responsible for removal of damaged bases, is of growing interest. The BER pathway is initiated by a set of enzymes known as DNA glycosylases. Unlike several downstream BER enzymes, DNA glycosylases have so far received little attention and the development of specific inhibitors of these enzymes has been lagging. Yet, dysregulation of DNA glycosylases is also known to play a central role in numerous cancers and at different stages of the disease, and thus inhibiting DNA glycosylases is now considered a valid strategy to eliminate cancer cells. This review provides a detailed overview of the activities of DNA glycosylases in normal and cancer cells, their modes of regulation, and their potential as anticancer drug targets.
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23
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Misztal T, Kowalczyk P, Młotkowska P, Marciniak E. The Effect of Allopregnanolone on Enzymatic Activity of the DNA Base Excision Repair Pathway in the Sheep Hippocampus and Amygdala under Natural and Stressful Conditions. Int J Mol Sci 2020; 21:E7762. [PMID: 33092287 PMCID: PMC7589085 DOI: 10.3390/ijms21207762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 10/15/2020] [Accepted: 10/19/2020] [Indexed: 01/24/2023] Open
Abstract
The neurosteroid allopregnanolone (AL) has many beneficial functions in the brain. This study tested the hypothesis that AL administered for three days into the third brain ventricle would affect the enzymatic activity of the DNA base excision repair (BER) pathway in the hippocampal CA1 and CA3 fields and the central amygdala in luteal-phase sheep under both natural and stressful conditions. Acute stressful stimuli, including isolation and partial movement restriction, were used on the last day of infusion. The results showed that stressful stimuli increased N-methylpurine DNA glycosylase (MPG), thymine DNA glycosylase (TDG), 8-oxoguanine glycosylase (OGG1), and AP-endonuclease 1 (APE1) mRNA expression, as well as repair activities for 1,N6-ethenoadenine (εA), 3,N4-ethenocytosine (εC), and 8-oxoguanine (8-oxoG) compared to controls. The stimulated events were lower in stressed and AL-treated sheep compared to sheep that were only stressed (except MPG mRNA expression in the CA1 and amygdala, as well as TDG mRNA expression in the CA1). AL alone reduced mRNA expression of all DNA repair enzymes (except TDG in the amygdala) relative to controls and other groups. DNA repair activities varied depending on the tissue-AL alone stimulated the excision of εA in the amygdala, εC in the CA3 and amygdala, and 8-oxoG in all tissues studied compared to controls. However, the excision efficiency of lesioned bases in the AL group was lower than in the stressed and stressed and AL-treated groups, with the exception of εA in the amygdala. In conclusion, the presented modulating effect of AL on the synthesis of BER pathway enzymes and their repair capacity, both under natural and stressful conditions, indicates another functional role of this neurosteroid in brain structures.
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Affiliation(s)
- Tomasz Misztal
- The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Instytucka 3, 05-110 Jabłonna, Poland; (P.K.); (P.M.); (E.M.)
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Mechetin GV, Endutkin AV, Diatlova EA, Zharkov DO. Inhibitors of DNA Glycosylases as Prospective Drugs. Int J Mol Sci 2020; 21:ijms21093118. [PMID: 32354123 PMCID: PMC7247160 DOI: 10.3390/ijms21093118] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 04/24/2020] [Accepted: 04/27/2020] [Indexed: 12/22/2022] Open
Abstract
DNA glycosylases are enzymes that initiate the base excision repair pathway, a major biochemical process that protects the genomes of all living organisms from intrinsically and environmentally inflicted damage. Recently, base excision repair inhibition proved to be a viable strategy for the therapy of tumors that have lost alternative repair pathways, such as BRCA-deficient cancers sensitive to poly(ADP-ribose)polymerase inhibition. However, drugs targeting DNA glycosylases are still in development and so far have not advanced to clinical trials. In this review, we cover the attempts to validate DNA glycosylases as suitable targets for inhibition in the pharmacological treatment of cancer, neurodegenerative diseases, chronic inflammation, bacterial and viral infections. We discuss the glycosylase inhibitors described so far and survey the advances in the assays for DNA glycosylase reactions that may be used to screen pharmacological libraries for new active compounds.
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Affiliation(s)
- Grigory V. Mechetin
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (G.V.M.); (A.V.E.); (E.A.D.)
| | - Anton V. Endutkin
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (G.V.M.); (A.V.E.); (E.A.D.)
| | - Evgeniia A. Diatlova
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (G.V.M.); (A.V.E.); (E.A.D.)
| | - Dmitry O. Zharkov
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (G.V.M.); (A.V.E.); (E.A.D.)
- Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
- Correspondence: ; Tel.: +7-383-363-5187
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Devesa-Guerra I, Morales-Ruiz T, Pérez-Roldán J, Parrilla-Doblas JT, Dorado-León M, García-Ortiz MV, Ariza RR, Roldán-Arjona T. DNA Methylation Editing by CRISPR-guided Excision of 5-Methylcytosine. J Mol Biol 2020; 432:2204-2216. [PMID: 32087201 DOI: 10.1016/j.jmb.2020.02.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 02/07/2020] [Accepted: 02/07/2020] [Indexed: 12/22/2022]
Abstract
Tools for actively targeted DNA demethylation are required to increase our knowledge about regulation and specific functions of this important epigenetic modification. DNA demethylation in mammals involves TET-mediated oxidation of 5-methylcytosine (5-meC), which may promote its replication-dependent dilution and/or active removal through base excision repair (BER). However, it is still unclear whether oxidized derivatives of 5-meC are simply DNA demethylation intermediates or rather epigenetic marks on their own. Unlike animals, plants have evolved enzymes that directly excise 5-meC without previous modification. In this work, we have fused the catalytic domain of Arabidopsis ROS1 5-meC DNA glycosylase to a CRISPR-associated null-nuclease (dCas9) and analyzed its capacity for targeted reactivation of methylation-silenced genes, in comparison to other dCas9-effectors. We found that dCas9-ROS1, but not dCas9-TET1, is able to reactivate methylation-silenced genes and induce partial demethylation in a replication-independent manner. We also found that reactivation induced by dCas9-ROS1, as well as that achieved by two different CRISPR-based chromatin effectors (dCas9-VP160 and dCas9-p300), generally decreases with methylation density. Our results suggest that plant 5-meC DNA glycosylases are a valuable addition to the CRISPR-based toolbox for epigenetic editing.
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Affiliation(s)
- Iván Devesa-Guerra
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071, Córdoba, Spain; Department of Genetics, University of Córdoba, 14071, Córdoba, Spain; Reina Sofía University Hospital, 14071, Córdoba, Spain
| | - Teresa Morales-Ruiz
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071, Córdoba, Spain; Department of Genetics, University of Córdoba, 14071, Córdoba, Spain; Reina Sofía University Hospital, 14071, Córdoba, Spain
| | - Juan Pérez-Roldán
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071, Córdoba, Spain; Department of Genetics, University of Córdoba, 14071, Córdoba, Spain; Reina Sofía University Hospital, 14071, Córdoba, Spain
| | - Jara Teresa Parrilla-Doblas
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071, Córdoba, Spain; Department of Genetics, University of Córdoba, 14071, Córdoba, Spain; Reina Sofía University Hospital, 14071, Córdoba, Spain
| | - Macarena Dorado-León
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071, Córdoba, Spain; Department of Genetics, University of Córdoba, 14071, Córdoba, Spain; Reina Sofía University Hospital, 14071, Córdoba, Spain
| | - María Victoria García-Ortiz
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071, Córdoba, Spain; Department of Genetics, University of Córdoba, 14071, Córdoba, Spain; Reina Sofía University Hospital, 14071, Córdoba, Spain
| | - Rafael R Ariza
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071, Córdoba, Spain; Department of Genetics, University of Córdoba, 14071, Córdoba, Spain; Reina Sofía University Hospital, 14071, Córdoba, Spain
| | - Teresa Roldán-Arjona
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071, Córdoba, Spain; Department of Genetics, University of Córdoba, 14071, Córdoba, Spain; Reina Sofía University Hospital, 14071, Córdoba, Spain.
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26
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Gredilla R, Sánchez-Román I, Gómez A, López-Torres M, Barja G. Mitochondrial base excision repair positively correlates with longevity in the liver and heart of mammals. GeroScience 2020; 42:653-65. [PMID: 31970600 DOI: 10.1007/s11357-020-00158-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 01/13/2020] [Indexed: 10/25/2022] Open
Abstract
Damage to DNA is especially important for aging. High DNA repair could contribute, in principle, to lower such damage in long-lived species. However, previous studies showed that repair of endogenous damage to nuclear DNA (base excision repair, BER) is negatively or not correlated with mammalian longevity. However, we hypothesize here that mitochondrial, instead of nuclear, BER is higher in long-lived than in short-lived mammals. We have thus measured activities and/or protein levels of various BER enzymes including DNA glycosylases, NTHL1 and NEIL2, and the APE endonuclease both in total and mitochondrial liver and heart fractions from up to eight mammalian species differing by 13-fold in longevity. Our results show, for the first time, a positive correlation between (mitochondrial) BER and mammalian longevity. This suggests that the low steady-state oxidative damage in mitochondrial DNA of long-lived species would be due to both their lower mitochondrial ROS generation and their higher mitochondrial BER. Long-lived mammals do not need to continuously maintain high nuclear BER levels because they release less mitROS to the cytosol. This can be the reason why they tend to show lower nuclear BER values. The higher mitochondrial BER of long-lived mammals contributes to their superior longevity, agrees with the updated version of the mitochondrial free radical theory of aging, and indicates the special relevance of mitochondria and mitROS for aging.
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27
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Abstract
Supplemental Digital Content is available in the text. Background: Atherosclerotic plaques demonstrate extensive accumulation of oxidative DNA damage, predominantly as 8-oxoguanine (8oxoG) lesions. 8oxoG is repaired by base excision repair enzymes; however, the mechanisms regulating 8oxoG accumulation in vascular smooth muscle cells (VSMCs) and its effects on their function and in atherosclerosis are unknown. Methods: We studied levels of 8oxoG and its regulatory enzymes in human atherosclerosis, the mechanisms regulating 8oxoG repair and the base excision repair enzyme 8oxoG DNA glycosylase I (OGG1) in VSMCs in vitro, and the effects of reducing 8oxoG in VSMCs in atherosclerosis in ApoE−/− mice. Results: Human plaque VSMCs showed defective nuclear 8oxoG repair, associated with reduced acetylation of OGG1. OGG1 was a key regulatory enzyme of 8oxoG repair in VSMCs, and its acetylation was crucial to its repair function through regulation of protein stability and expression. p300 and sirtuin 1 were identified as the OGG1 acetyltransferase and deacetylase regulators, respectively, and both proteins interacted with OGG1 and regulated OGG1 acetylation at endogenous levels. However, p300 levels were decreased in human plaque VSMCs and in response to oxidative stress, suggesting that reactive oxygen species–induced regulation of OGG1 acetylation could be caused by reactive oxygen species–induced decrease in p300 expression. We generated mice that express VSMC-restricted OGG1 or an acetylation defective version (SM22α-OGG1 and SM22α-OGG1K-R mice) and crossed them with ApoE−/− mice. We also studied ApoE−/− mice deficient in OGG1 (OGG1−/−). OGG1−/− mice showed increased 8oxoG in vivo and increased atherosclerosis, whereas mice expressing VSMC-specific OGG1 but not the acetylation mutant OGG1K-R showed markedly reduced intracellular 8oxoG and reduced atherosclerosis. VSMC OGG1 reduced telomere 8oxoG accumulation, DNA strand breaks, cell death and senescence after oxidant stress, and activation of proinflammatory pathways. Conclusions: We identify defective 8oxoG base excision repair in human atherosclerotic plaque VSMCs, OGG1 as a major 8oxoG repair enzyme in VSMCs, and p300/sirtuin 1 as major regulators of OGG1 through acetylation/deacetylation. Reducing oxidative damage by rescuing OGG1 activity reduces plaque development, indicating the detrimental effects of 8oxoG on VSMC function.
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MESH Headings
- Acetylation
- Animals
- Atherosclerosis/genetics
- Atherosclerosis/metabolism
- Atherosclerosis/pathology
- Biomarkers/metabolism
- Cells, Cultured
- DNA Damage
- DNA Glycosylases/deficiency
- DNA Glycosylases/genetics
- DNA Glycosylases/metabolism
- DNA Repair
- Disease Models, Animal
- Female
- Guanine/analogs & derivatives
- Guanine/metabolism
- Humans
- Male
- Mice, Knockout, ApoE
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Oxidative Stress
- Plaque, Atherosclerotic
- Protein Processing, Post-Translational
- Rats
- Sirtuin 1/genetics
- Sirtuin 1/metabolism
- p300-CBP Transcription Factors/metabolism
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Affiliation(s)
- Aarti Shah
- Division of Cardiovascular Medicine, University of Cambridge, Addenbrooke’s Centre for Clinical Investigation, Addenbrooke’s Hospital, United Kingdom. Dr Gray is currently at Cardiovascular Safety, AstraZeneca, Cambridge, United Kingdom
| | - Kelly Gray
- Division of Cardiovascular Medicine, University of Cambridge, Addenbrooke’s Centre for Clinical Investigation, Addenbrooke’s Hospital, United Kingdom. Dr Gray is currently at Cardiovascular Safety, AstraZeneca, Cambridge, United Kingdom
| | - Nichola Figg
- Division of Cardiovascular Medicine, University of Cambridge, Addenbrooke’s Centre for Clinical Investigation, Addenbrooke’s Hospital, United Kingdom. Dr Gray is currently at Cardiovascular Safety, AstraZeneca, Cambridge, United Kingdom
| | - Alison Finigan
- Division of Cardiovascular Medicine, University of Cambridge, Addenbrooke’s Centre for Clinical Investigation, Addenbrooke’s Hospital, United Kingdom. Dr Gray is currently at Cardiovascular Safety, AstraZeneca, Cambridge, United Kingdom
| | - Lakshi Starks
- Division of Cardiovascular Medicine, University of Cambridge, Addenbrooke’s Centre for Clinical Investigation, Addenbrooke’s Hospital, United Kingdom. Dr Gray is currently at Cardiovascular Safety, AstraZeneca, Cambridge, United Kingdom
| | - Martin Bennett
- Division of Cardiovascular Medicine, University of Cambridge, Addenbrooke’s Centre for Clinical Investigation, Addenbrooke’s Hospital, United Kingdom. Dr Gray is currently at Cardiovascular Safety, AstraZeneca, Cambridge, United Kingdom
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28
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Parrilla-Doblas JT, Roldán-Arjona T, Ariza RR, Córdoba-Cañero D. Active DNA Demethylation in Plants. Int J Mol Sci 2019; 20:E4683. [PMID: 31546611 PMCID: PMC6801703 DOI: 10.3390/ijms20194683] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 09/17/2019] [Accepted: 09/19/2019] [Indexed: 02/06/2023] Open
Abstract
Methylation of cytosine (5-meC) is a critical epigenetic modification in many eukaryotes, and genomic DNA methylation landscapes are dynamically regulated by opposed methylation and demethylation processes. Plants are unique in possessing a mechanism for active DNA demethylation involving DNA glycosylases that excise 5-meC and initiate its replacement with unmodified C through a base excision repair (BER) pathway. Plant BER-mediated DNA demethylation is a complex process involving numerous proteins, as well as additional regulatory factors that avoid accumulation of potentially harmful intermediates and coordinate demethylation and methylation to maintain balanced yet flexible DNA methylation patterns. Active DNA demethylation counteracts excessive methylation at transposable elements (TEs), mainly in euchromatic regions, and one of its major functions is to avoid methylation spreading to nearby genes. It is also involved in transcriptional activation of TEs and TE-derived sequences in companion cells of male and female gametophytes, which reinforces transposon silencing in gametes and also contributes to gene imprinting in the endosperm. Plant 5-meC DNA glycosylases are additionally involved in many other physiological processes, including seed development and germination, fruit ripening, and plant responses to a variety of biotic and abiotic environmental stimuli.
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Affiliation(s)
- Jara Teresa Parrilla-Doblas
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071 Córdoba, Spain.
- Department of Genetics, University of Córdoba, 14071 Córdoba, Spain.
- Reina Sofía University Hospital, 14071 Córdoba, Spain.
| | - Teresa Roldán-Arjona
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071 Córdoba, Spain.
- Department of Genetics, University of Córdoba, 14071 Córdoba, Spain.
- Reina Sofía University Hospital, 14071 Córdoba, Spain.
| | - Rafael R Ariza
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071 Córdoba, Spain.
- Department of Genetics, University of Córdoba, 14071 Córdoba, Spain.
- Reina Sofía University Hospital, 14071 Córdoba, Spain.
| | - Dolores Córdoba-Cañero
- Maimónides Biomedical Research Institute of Córdoba (IMIBIC), 14071 Córdoba, Spain.
- Department of Genetics, University of Córdoba, 14071 Córdoba, Spain.
- Reina Sofía University Hospital, 14071 Córdoba, Spain.
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29
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Abstract
Endogenous and exogenous oxidative agents continuously damage genomic DNA, with the brain being particularly vulnerable. Thus, preserving genomic integrity is key for brain health and neuronal function. Accumulation of DNA damage is one of the causative factors of ageing and increases the risk of a wide range of neurological disorders. Base excision repair is the major pathway for removal of oxidized bases in the genome and initiated by DNA glycosylases. Emerging evidence suggest that DNA glycosylases have non-canonical functions important for genome regulation. Understanding canonical and non-canonical functions of DNA glycosylases processing oxidative base lesions modulating brain function will be crucial for the development of novel therapeutic strategies.
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Affiliation(s)
- Katja Scheffler
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Norway; Clinic of Laboratory Medicine, St. Olavs Hospital, N-7491 Trondheim, Norway
| | - Karine Øian Bjørås
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Norway
| | - Magnar Bjørås
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Norway; Clinic of Laboratory Medicine, St. Olavs Hospital, N-7491 Trondheim, Norway; Department of Microbiology, Oslo University Hospital and University of Oslo, N-0424 Oslo, Norway.
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30
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Boldinova EO, Khairullin RF, Makarova AV, Zharkov DO. Isoforms of Base Excision Repair Enzymes Produced by Alternative Splicing. Int J Mol Sci 2019; 20:ijms20133279. [PMID: 31277343 PMCID: PMC6651865 DOI: 10.3390/ijms20133279] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 06/29/2019] [Accepted: 07/02/2019] [Indexed: 02/07/2023] Open
Abstract
Transcripts of many enzymes involved in base excision repair (BER) undergo extensive alternative splicing, but functions of the corresponding alternative splice variants remain largely unexplored. In this review, we cover the studies describing the common alternatively spliced isoforms and disease-associated variants of DNA glycosylases, AP-endonuclease 1, and DNA polymerase beta. We also discuss the roles of alternative splicing in the regulation of their expression, catalytic activities, and intracellular transport.
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Affiliation(s)
| | - Rafil F Khairullin
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 9 Parizhskoy Kommuny Str., 420012 Kazan, Russia
| | - Alena V Makarova
- RAS Institute of Molecular Genetics, 2 Kurchatova Sq., 123182 Moscow, Russia.
| | - Dmitry O Zharkov
- Novosibirsk State University, 1 Pirogova St., 630090 Novosibirsk, Russia.
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia.
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31
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Abstract
Transient protein-protein complexes are of great importance for organizing multiple enzymatic reactions into productive reaction pathways. Base excision repair (BER), a process of critical importance for maintaining genome stability against a plethora of DNA-damaging factors, involves several enzymes, including DNA glycosylases, AP endonucleases, DNA polymerases, DNA ligases and accessory proteins acting sequentially on the same damaged site in DNA. Rather than being assembled into one stable multisubunit complex, these enzymes pass the repair intermediates between them in a highly coordinated manner. In this review, we discuss the nature and the role of transient complexes arising during BER as deduced from structural and kinetic data. Almost all of the transient complexes are DNA-mediated, although some may also exist in solution and strengthen under specific conditions. The best-studied example, the interactions between DNA glycosylases and AP endonucleases, is discussed in more detail to provide a framework for distinguishing between stable and transient complexes based on the kinetic data. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Anton V Endutkin
- SB RAS Institute of Chemical Biology and Fundamental Medicine , Novosibirsk , Russia.,Novosibirsk State University , Novosibirsk , Russia.,Podalirius Ltd. , Novosibirsk , Russia
| | - Anna V Yudkina
- SB RAS Institute of Chemical Biology and Fundamental Medicine , Novosibirsk , Russia.,Novosibirsk State University , Novosibirsk , Russia
| | - Viktoriya S Sidorenko
- Department of Pharmacological Sciences, Stony Brook University , Stony Brook , NY , USA
| | - Dmitry O Zharkov
- SB RAS Institute of Chemical Biology and Fundamental Medicine , Novosibirsk , Russia.,Novosibirsk State University , Novosibirsk , Russia
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32
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Lee AJ, Wallace SS. Hide and seek: How do DNA glycosylases locate oxidatively damaged DNA bases amidst a sea of undamaged bases? Free Radic Biol Med 2017; 107:170-178. [PMID: 27865982 PMCID: PMC5433924 DOI: 10.1016/j.freeradbiomed.2016.11.024] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 11/11/2016] [Accepted: 11/13/2016] [Indexed: 01/10/2023]
Abstract
The first step of the base excision repair (BER) pathway responsible for removing oxidative DNA damage utilizes DNA glycosylases to find and remove the damaged DNA base. How glycosylases find the damaged base amidst a sea of undamaged bases has long been a question in the BER field. Single molecule total internal reflection fluorescence microscopy (SM TIRFM) experiments have allowed for an exciting look into this search mechanism and have found that DNA glycosylases scan along the DNA backbone in a bidirectional and random fashion. By comparing the search behavior of bacterial glycosylases from different structural families and with varying substrate specificities, it was found that glycosylases search for damage by periodically inserting a wedge residue into the DNA stack as they redundantly search tracks of DNA that are 450-600bp in length. These studies open up a wealth of possibilities for further study in real time of the interactions of DNA glycosylases and other BER enzymes with various DNA substrates.
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Affiliation(s)
- Andrea J Lee
- Department of Microbiology and Molecular Genetics, The Markey Center for Molecular Genetics, The University of Vermont, 95 Carrigan Drive, Burlington, VT 05405, USA
| | - Susan S Wallace
- Department of Microbiology and Molecular Genetics, The Markey Center for Molecular Genetics, The University of Vermont, 95 Carrigan Drive, Burlington, VT 05405, USA.
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33
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D'Errico M, Parlanti E, Pascucci B, Fortini P, Baccarini S, Simonelli V, Dogliotti E. Single nucleotide polymorphisms in DNA glycosylases: From function to disease. Free Radic Biol Med 2017; 107:278-291. [PMID: 27932076 DOI: 10.1016/j.freeradbiomed.2016.12.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 11/25/2016] [Accepted: 12/02/2016] [Indexed: 02/08/2023]
Abstract
Oxidative stress is associated with a growing number of diseases that span from cancer to neurodegeneration. Most oxidatively induced DNA base lesions are repaired by the base excision repair (BER) pathway which involves the action of various DNA glycosylases. There are numerous genome wide studies attempting to associate single-nucleotide polymorphisms (SNPs) with predispositions to various types of disease; often, these common variants do not have significant alterations in their biochemical function and do not exhibit a convincing phenotype. Nevertheless several lines of evidence indicate that SNPs in DNA repair genes may modulate DNA repair capacity and contribute to risk of disease. This overview provides a convincing picture that SNPs of DNA glycosylases that remove oxidatively generated DNA lesions are susceptibility factors for a wide disease spectrum that includes besides cancer (particularly lung, breast and gastrointestinal tract), cochlear/ocular disorders, myocardial infarction and neurodegenerative disorders which can be all grouped under the umbrella of oxidative stress-related pathologies.
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Affiliation(s)
- Mariarosaria D'Errico
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
| | - Eleonora Parlanti
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy
| | - Barbara Pascucci
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy; Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Via Salaria, Km 29,300, 00016 Monterotondo Stazione, Rome, Italy
| | - Paola Fortini
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy
| | - Sara Baccarini
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy
| | - Valeria Simonelli
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy
| | - Eugenia Dogliotti
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
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34
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Dizdaroglu M, Coskun E, Jaruga P. Repair of oxidatively induced DNA damage by DNA glycosylases: Mechanisms of action, substrate specificities and excision kinetics. Mutat Res Rev Mutat Res 2017; 771:99-127. [PMID: 28342455 DOI: 10.1016/j.mrrev.2017.02.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Indexed: 02/07/2023]
Abstract
Endogenous and exogenous reactive species cause oxidatively induced DNA damage in living organisms by a variety of mechanisms. As a result, a plethora of mutagenic and/or cytotoxic products are formed in cellular DNA. This type of DNA damage is repaired by base excision repair, although nucleotide excision repair also plays a limited role. DNA glycosylases remove modified DNA bases from DNA by hydrolyzing the glycosidic bond leaving behind an apurinic/apyrimidinic (AP) site. Some of them also possess an accompanying AP-lyase activity that cleaves the sugar-phosphate chain of DNA. Since the first discovery of a DNA glycosylase, many studies have elucidated the mechanisms of action, substrate specificities and excision kinetics of these enzymes present in all living organisms. For this purpose, most studies used single- or double-stranded oligodeoxynucleotides with a single DNA lesion embedded at a defined position. High-molecular weight DNA with multiple base lesions has been used in other studies with the advantage of the simultaneous investigation of many DNA base lesions as substrates. Differences between the substrate specificities and excision kinetics of DNA glycosylases have been found when these two different substrates were used. Some DNA glycosylases possess varying substrate specificities for either purine-derived lesions or pyrimidine-derived lesions, whereas others exhibit cross-activity for both types of lesions. Laboratory animals with knockouts of the genes of DNA glycosylases have also been used to provide unequivocal evidence for the substrates, which had previously been found in in vitro studies, to be the actual substrates in vivo as well. On the basis of the knowledge gained from the past studies, efforts are being made to discover small molecule inhibitors of DNA glycosylases that may be used as potential drugs in cancer therapy.
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35
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Calkins MJ, Vartanian V, Owen N, Kirkali G, Jaruga P, Dizdaroglu M, McCullough AK, Lloyd RS. Enhanced sensitivity of Neil1 -/- mice to chronic UVB exposure. DNA Repair (Amst) 2016; 48:43-50. [PMID: 27818081 DOI: 10.1016/j.dnarep.2016.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/17/2016] [Accepted: 10/27/2016] [Indexed: 01/02/2023]
Abstract
Oxidative stress and reactive oxygen species (ROS)-induced DNA base damage are thought to be central mediators of UV-induced carcinogenesis and skin aging. However, increased steady-state levels of ROS-induced DNA base damage have not been reported after chronic UV exposure. Accumulation of ROS-induced DNA base damage is governed by rates of lesion formation and repair. Repair is generally performed by Base Excision Repair (BER), which is initiated by DNA glycosylases, such as 8-oxoguanine glycosylase and Nei-Endonuclease VIII-Like 1 (NEIL1). In the current study, UV light (UVB) was used to elicit protracted low-level ROS challenge in wild-type (WT) and Neil1-/- mouse skin. Relative to WT controls, Neil1-/- mice showed an increased sensitivity to tissue destruction from the chronic UVB exposure, and corresponding enhanced chronic inflammatory responses as measured by cytokine message levels and profiling, as well as neutrophil infiltration. Additionally, levels of several ROS-induced DNA lesions were measured including 4,6-diamino-5-formamidopyrimidine (FapyGua), 2,6-diamino-4-hydroxy-5-formamidopyrimidine (FapyAde), 8-hydroxyguanine (8-OH-Gua), 5,6-dihydroxyuracil (5,6-diOH-Ura) and thymine glycol (ThyGly). In WT mice, chronic UVB exposure led to increased steady-state levels of FapyGua, FapyAde, and ThyGly with no significant increases in 8-OH-Gua or 5,6-diOH-Ura. Interestingly, the lesions that accumulated were all substrates of NEIL1. Collectively, these data suggest that NEIL1-initiated repair of a subset of ROS-induced DNA base lesions may be insufficient to prevent the initiation of inflammatory pathways during chronic UV exposure in mouse skin.
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Affiliation(s)
- Marcus J Calkins
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University Portland, OR 97239-3098, United States
| | - Vladimir Vartanian
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University Portland, OR 97239-3098, United States
| | - Nichole Owen
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University Portland, OR 97239-3098, United States
| | - Guldal Kirkali
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg MD 20899-8311, United States
| | - Pawel Jaruga
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg MD 20899-8311, United States
| | - Miral Dizdaroglu
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg MD 20899-8311, United States
| | - Amanda K McCullough
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University Portland, OR 97239-3098, United States; Department of Molecular and Medical Genetics, Oregon Health & Science University Portland, OR 97239-3098, United States
| | - R Stephen Lloyd
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University Portland, OR 97239-3098, United States; Department of Physiology and Pharmacology, Oregon Health & Science University Portland, OR 97239-3098, United States.
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Skarpengland T, Dahl TB, Skjelland M, Scheffler K, de Sousa MML, Gregersen I, Kuśnierczyk A, Sharma A, Slupphaug G, Eide L, Segers FM, Skagen KR, Dahl CP, Russell D, Folkersen L, Krohg-Sørensen K, Holm S, Bjørås M, Aukrust P, Halvorsen B. Enhanced base excision repair capacity in carotid atherosclerosis may protect nuclear DNA but not mitochondrial DNA. Free Radic Biol Med 2016; 97:386-397. [PMID: 27381496 DOI: 10.1016/j.freeradbiomed.2016.07.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 06/13/2016] [Accepted: 07/01/2016] [Indexed: 01/05/2023]
Abstract
BACKGROUND Lesional and systemic oxidative stress has been implicated in the pathogenesis of atherosclerosis, potentially leading to accumulation of DNA base lesions within atherosclerotic plaques. Although base excision repair (BER) is a major pathway counteracting oxidative DNA damage, our knowledge on BER and accumulation of DNA base lesions in clinical atherosclerosis is scarce. Here, we evaluated the transcriptional profile of a wide spectrum of BER components as well as DNA damage accumulation in atherosclerotic and non-atherosclerotic arteries. METHODS BER gene expression levels were analyzed in 162 carotid plaques, 8 disease-free carotid specimens from patients with carotid plaques and 10 non-atherosclerotic control arteries. Genomic integrity, mitochondrial (mt) DNA copy number, oxidative DNA damage and BER proteins were evaluated in a subgroup of plaques and controls. RESULTS Our major findings were: (i) The BER pathway showed a global increased transcriptional response in plaques as compared to control arteries, accompanied by increased expression of several BER proteins. (ii) Whereas nuclear DNA stability was maintained within carotid plaques, mtDNA integrity and copy number were decreased. (iii) Within carotid plaques, mRNA levels of several BER genes correlated with macrophage markers. (iv) In vitro, some of the BER genes were highly expressed in the anti-inflammatory and pro-resolving M2 macrophages, showing increased expression upon exposure to modified lipids. CONCLUSIONS The increased transcriptional response of BER genes in atherosclerosis may contribute to lesional nuclear DNA stability but appears insufficient to maintain mtDNA integrity, potentially influencing mitochondrial function in cells within the atherosclerotic lesion.
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Affiliation(s)
- Tonje Skarpengland
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
| | - Tuva B Dahl
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Mona Skjelland
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Norway; Department of Neurology, Oslo University Hospital Rikshospitalet, Norway
| | - Katja Scheffler
- Department of Medical Biochemistry, Oslo University Hospital Rikshospitalet, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Mirta Mittelsted Leal de Sousa
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway; PROMEC Core Facility for Proteomics and Metabolomics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Ida Gregersen
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Anna Kuśnierczyk
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway; PROMEC Core Facility for Proteomics and Metabolomics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Animesh Sharma
- PROMEC Core Facility for Proteomics and Metabolomics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Geir Slupphaug
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway; PROMEC Core Facility for Proteomics and Metabolomics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Lars Eide
- Department of Medical Biochemistry, Oslo University Hospital Rikshospitalet, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Filip M Segers
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Norway
| | | | - Christen P Dahl
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Norway; Department of Cardiology, Oslo University Hospital Rikshospitalet, Norway; Center of Heart Failure Research, University of Oslo, Oslo, Norway
| | - David Russell
- Department of Neurology, Oslo University Hospital Rikshospitalet, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Lasse Folkersen
- Center for Biological Sequence Analysis, Technical University of Denmark, Copenhagen, Denmark
| | - Kirsten Krohg-Sørensen
- Department of Thoracic and Cardiovascular Surgery, Oslo University Hospital Rikshospitalet, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Sverre Holm
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Norway; Lillehammer Hospital for Rheumatic Diseases, Lillehammer, Norway
| | - Magnar Bjørås
- Department of Microbiology, Oslo University Hospital Rikshospitalet, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Pål Aukrust
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Norway; Section of Clinical Immunology and Infectious Diseases, Oslo University Hospital Rikshospitalet, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway; K.G. Jebsen Inflammatory Research Center, University of Oslo, Oslo, Norway
| | - Bente Halvorsen
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway; K.G. Jebsen Inflammatory Research Center, University of Oslo, Oslo, Norway
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Abstract
The Base Excision Repair (BER) pathway removes the vast majority of damages produced by ionizing radiation, including the plethora of radiation-damaged purines and pyrimidines. The first enzymes in the BER pathway are DNA glycosylases, which are responsible for finding and removing the damaged base. Although much is known about the biochemistry of DNA glycosylases, how these enzymes locate their specific damage substrates among an excess of undamaged bases has long remained a mystery. Here we describe the use of single molecule fluorescence to observe the bacterial DNA glycosylases, Nth, Fpg and Nei, scanning along undamaged and damaged DNA. We show that all three enzymes randomly diffuse on the DNA molecule and employ a wedge residue to search for and locate damage. The search behavior of the Escherichia coli DNA glycosylases likely provides a paradigm for their homologous mammalian counterparts.
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Affiliation(s)
- Andrea J Lee
- Department of Microbiology and Molecular Genetics, The Markey Center for Molecular Genetics, The University of Vermont, 95 Carrigan Drive, Burlington, Vermont, 05405, USA
| | - Susan S Wallace
- Department of Microbiology and Molecular Genetics, The Markey Center for Molecular Genetics, The University of Vermont, 95 Carrigan Drive, Burlington, Vermont, 05405, USA
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Kuznetsov NA, Kiryutin AS, Kuznetsova AA, Panov MS, Barsukova MO, Yurkovskaya AV, Fedorova OS. The formation of catalytically competent enzyme-substrate complex is not a bottleneck in lesion excision by human alkyladenine DNA glycosylase. J Biomol Struct Dyn 2016; 35:950-967. [PMID: 27025273 DOI: 10.1080/07391102.2016.1171800] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Human alkyladenine DNA glycosylase (AAG) protects DNA from alkylated and deaminated purine lesions. AAG flips out the damaged nucleotide from the double helix of DNA and catalyzes the hydrolysis of the N-glycosidic bond to release the damaged base. To understand better, how the step of nucleotide eversion influences the overall catalytic process, we performed a pre-steady-state kinetic analysis of AAG interaction with specific DNA-substrates, 13-base pair duplexes containing in the 7th position 1-N6-ethenoadenine (εA), hypoxanthine (Hx), and the stable product analogue tetrahydrofuran (F). The combination of the fluorescence of tryptophan, 2-aminopurine, and 1-N6-ethenoadenine was used to record conformational changes of the enzyme and DNA during the processes of DNA lesion recognition, damaged base eversion, excision of the N-glycosidic bond, and product release. The thermal stability of the duplexes characterized by the temperature of melting, Tm, and the rates of spontaneous opening of individual nucleotide base pairs were determined by NMR spectroscopy. The data show that the relative thermal stability of duplexes containing a particular base pair in position 7, (Tm(F/T) < Tm(εA/T) < Tm(Hx/T) < Tm(A/T)) correlates with the rate of reversible spontaneous opening of the base pair. However, in contrast to that, the catalytic lesion excision rate is two orders of magnitude higher for Hx-containing substrates than for substrates containing εA, proving that catalytic activity is not correlated with the stability of the damaged base pair. Our study reveals that the formation of the catalytically competent enzyme-substrate complex is not the bottleneck controlling the catalytic activity of AAG.
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Affiliation(s)
- N A Kuznetsov
- a Institute of Chemical Biology and Fundamental Medicine , Lavrentyev Ave. 8, Novosibirsk 630090 , Russia.,c Department of Natural Sciences , Novosibirsk State University , Pirogova St. 2, Novosibirsk 630090 , Russia
| | - A S Kiryutin
- b International Tomography Center SB RAS, Institutskaya 3a , Novosibirsk 630090 , Russia.,c Department of Natural Sciences , Novosibirsk State University , Pirogova St. 2, Novosibirsk 630090 , Russia
| | - A A Kuznetsova
- a Institute of Chemical Biology and Fundamental Medicine , Lavrentyev Ave. 8, Novosibirsk 630090 , Russia
| | - M S Panov
- b International Tomography Center SB RAS, Institutskaya 3a , Novosibirsk 630090 , Russia.,c Department of Natural Sciences , Novosibirsk State University , Pirogova St. 2, Novosibirsk 630090 , Russia
| | - M O Barsukova
- c Department of Natural Sciences , Novosibirsk State University , Pirogova St. 2, Novosibirsk 630090 , Russia
| | - A V Yurkovskaya
- b International Tomography Center SB RAS, Institutskaya 3a , Novosibirsk 630090 , Russia.,c Department of Natural Sciences , Novosibirsk State University , Pirogova St. 2, Novosibirsk 630090 , Russia
| | - O S Fedorova
- a Institute of Chemical Biology and Fundamental Medicine , Lavrentyev Ave. 8, Novosibirsk 630090 , Russia
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Synowiec E, Wójcik KA, Czubatka A, Polakowski P, Izdebska J, Szaflik J, Błasiak J, Szaflik JP. Lack of association between polymorphisms of the DNA base excision repair genes MUTYH and hOGG1 and keratoconus in a Polish subpopulation. Arch Med Sci 2015; 11:1101-10. [PMID: 26528356 PMCID: PMC4624754 DOI: 10.5114/aoms.2015.54867] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 09/28/2013] [Accepted: 10/18/2013] [Indexed: 12/12/2022] Open
Abstract
INTRODUCTION Keratoconus (KC) is a non-inflammatory thinning of the cornea and a leading indication for corneal transplantation. Oxidative stress plays a role in the pathogenesis of this disease. The products of the hOGG1 and MUTYH genes play an important role in the repair of oxidatively modified DNA in the base excision repair pathway. We hypothesized that variability in these genes may change susceptibility to oxidative stress and predispose individuals to the development of KC. We investigated the possible association between the c.977C>G polymorphism of the hOGG1 gene (rs1052133) and the c.972G>C polymorphism of the MUTYH gene (rs3219489) and KC occurrence as well as the modulation of this association by some KC risk factors. MATERIAL AND METHODS A total of 205 patients with KC and 220 controls were included in this study. The polymorphisms were genotyped with polymerase chain reaction (PCR) restriction fragment length polymorphism and PCR-confronting two-pair primer techniques. Differences in genotype and allele frequency distributions were evaluated using the χ(2) test, and KC risk was estimated with an unconditional multiple logistic regression with and without adjustment for co-occurrence of visual impairment, allergies, sex and family history for KC. RESULTS We did not find any association between the genotypes and combined genotypes of the c.977C>G polymorphism of the hOGG1 gene and the c.972G>C polymorphism of the MUTYH gene and the occurrence of KC. CONCLUSIONS Our findings suggest that the c.977C>G-hOGG1 polymorphism and the c.972G>C-MUTYH polymorphism may not be linked with KC occurrence in this Polish subpopulation.
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Affiliation(s)
- Ewelina Synowiec
- Department of Molecular Genetics, University of Lodz, Lodz, Poland
| | | | - Anna Czubatka
- Department of Molecular Genetics, University of Lodz, Lodz, Poland
| | - Piotr Polakowski
- Department of Ophthalmology, Medical University of Warsaw, SPKSO Ophthalmic University Hospital, Warsaw, Poland
| | - Justyna Izdebska
- Department of Ophthalmology, Medical University of Warsaw, SPKSO Ophthalmic University Hospital, Warsaw, Poland
| | - Jerzy Szaflik
- Department of Ophthalmology, Medical University of Warsaw, SPKSO Ophthalmic University Hospital, Warsaw, Poland
| | - Janusz Błasiak
- Department of Molecular Genetics, University of Lodz, Lodz, Poland
| | - Jacek P. Szaflik
- Department of Ophthalmology, Medical University of Warsaw, SPKSO Ophthalmic University Hospital, Warsaw, Poland
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Meng H, Cao Y, Qin J, Song X, Zhang Q, Shi Y, Cao L. DNA methylation, its mediators and genome integrity. Int J Biol Sci 2015; 11:604-17. [PMID: 25892967 PMCID: PMC4400391 DOI: 10.7150/ijbs.11218] [Citation(s) in RCA: 151] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 03/02/2015] [Indexed: 12/18/2022] Open
Abstract
DNA methylation regulates many cellular processes, including embryonic development, transcription, chromatin structure, X-chromosome inactivation, genomic imprinting and chromosome stability. DNA methyltransferases establish and maintain the presence of 5-methylcytosine (5mC), and ten-eleven translocation cytosine dioxygenases (TETs) oxidise 5mC to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC), which can be removed by base excision repair (BER) proteins. Multiple forms of DNA methylation are recognised by methyl-CpG binding proteins (MeCPs), which play vital roles in chromatin-based transcriptional regulation, DNA repair and replication. Accordingly, defects in DNA methylation and its mediators may cause silencing of tumour suppressor genes and misregulation of multiple cell cycles, DNA repair and chromosome stability genes, and hence contribute to genome instability in various human diseases, including cancer. Thus, understanding functional genetic mutations and aberrant expression of these DNA methylation mediators is critical to deciphering the crosstalk between concurrent genetic and epigenetic alterations in specific cancer types and to the development of new therapeutic strategies.
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Affiliation(s)
- Huan Meng
- 1. Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, Shenyang 110001, China; ; 2. MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing Biomedical Research Institute, Nanjing University, China
| | - Ying Cao
- 2. MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing Biomedical Research Institute, Nanjing University, China
| | - Jinzhong Qin
- 2. MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing Biomedical Research Institute, Nanjing University, China
| | - Xiaoyu Song
- 1. Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, Shenyang 110001, China
| | - Qing Zhang
- 2. MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing Biomedical Research Institute, Nanjing University, China
| | - Yun Shi
- 2. MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing Biomedical Research Institute, Nanjing University, China
| | - Liu Cao
- 1. Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, Shenyang 110001, China
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41
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Dizdaroglu M. Oxidatively induced DNA damage and its repair in cancer. Mutat Res Rev Mutat Res. 2015;763:212-245. [PMID: 25795122 DOI: 10.1016/j.mrrev.2014.11.002] [Citation(s) in RCA: 173] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 11/03/2014] [Accepted: 11/04/2014] [Indexed: 12/28/2022]
Abstract
Oxidatively induced DNA damage is caused in living organisms by endogenous and exogenous reactive species. DNA lesions resulting from this type of damage are mutagenic and cytotoxic and, if not repaired, can cause genetic instability that may lead to disease processes including carcinogenesis. Living organisms possess DNA repair mechanisms that include a variety of pathways to repair multiple DNA lesions. Mutations and polymorphisms also occur in DNA repair genes adversely affecting DNA repair systems. Cancer tissues overexpress DNA repair proteins and thus develop greater DNA repair capacity than normal tissues. Increased DNA repair in tumors that removes DNA lesions before they become toxic is a major mechanism for development of resistance to therapy, affecting patient survival. Accumulated evidence suggests that DNA repair capacity may be a predictive biomarker for patient response to therapy. Thus, knowledge of DNA protein expressions in normal and cancerous tissues may help predict and guide development of treatments and yield the best therapeutic response. DNA repair proteins constitute targets for inhibitors to overcome the resistance of tumors to therapy. Inhibitors of DNA repair for combination therapy or as single agents for monotherapy may help selectively kill tumors, potentially leading to personalized therapy. Numerous inhibitors have been developed and are being tested in clinical trials. The efficacy of some inhibitors in therapy has been demonstrated in patients. Further development of inhibitors of DNA repair proteins is globally underway to help eradicate cancer.
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Abstract
This perspective reviews the many dimensions of base excision repair from a 10,000 foot vantage point and provides one person's view on where the field is headed. Enzyme function is considered under the lens of X-ray diffraction and single molecule studies. Base excision repair in chromatin and telomeres, regulation of expression and the role of posttranslational modifications are also discussed in the context of enzyme activities, cellular localization and interacting partners. The specialized roles that base excision repair play in transcriptional activation by active demethylation and targeted oxidation as well as how base excision repair functions in the immune processes of somatic hypermutation and class switch recombination and its possible involvement in retroviral infection are also discussed. Finally the complexities of oxidative damage and its repair and its link to neurodegenerative disorders, as well as the role of base excision repair as a tumor suppressor are examined in the context of damage, repair and aging. By outlining the many base excision repair-related mysteries that have yet to be unraveled, hopefully this perspective will stimulate further interest in the field.
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Affiliation(s)
- Susan S Wallace
- Department of Microbiology and Molecular Genetics, The Markey Center for Molecular Genetics, The University of Vermont, 95 Carrigan Drive, Stafford Hall, Burlington, VT 05405-0084, USA.
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Chatterjee N, Eom HJ, Choi J. Effects of silver nanoparticles on oxidative DNA damage-repair as a function of p38 MAPK status: a comparative approach using human Jurkat T cells and the nematode Caenorhabditis elegans. Environ Mol Mutagen 2014; 55:122-133. [PMID: 24347047 DOI: 10.1002/em.21844] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 11/19/2013] [Accepted: 12/01/2013] [Indexed: 06/03/2023]
Abstract
The large-scale use of silver nanoparticles (AgNPs) has raised concerns over potential impacts on the environment and human health. We previously reported that AgNP exposure causes an increase in reactive oxygen species, DNA damage, and induction of p38 MAPK and PMK-1 in Jurkat T cells and in Caenorhabditis elegans. To elucidate the underlying mechanisms of AgNP toxicity, here we evaluate the effects of AgNPs on oxidative DNA damage-repair (in human and C. elegans DNA glycosylases hOGG1, hNTH1, NTH-1, and 8-oxo-GTPases-hMTH1, NDX-4) and explore the role of p38 MAPK and PMK-1 in this process. Our comparative approach examined viability, gene expression, and enzyme activities in wild type (WT) and p38 MAPK knock-down (KD) Jurkat T cells (in vitro) and in WT and pmk-1 loss-of-function mutant strains of C. elegans (in vivo). The results suggest that p38 MAPK/PMK-1 plays protective role against AgNP-mediated toxicity, reduced viability and greater accumulation of 8OHdG was observed in AgNP-treated KD cells, and in pmk-1 mutant worms compared with their WT counterparts, respectively. Furthermore, dose-dependent alterations in hOGG1, hMTH1, and NDX-4 expression and enzyme activity, and survival in ndx-4 mutant worms occurred following AgNP exposure. Interestingly, the absence or depletion of p38 MAPK/PMK-1 caused impaired and additive effects in AgNP-induced ndx-4(ok1003); pmk-1(RNAi) mutant survival, and hOGG1 and NDX-4 expression and enzyme activity, which may lead to higher accumulation of 8OHdG. Together, the results indicate that p38 MAPK/PMK-1 plays an important protective role in AgNP-induced oxidative DNA damage-repair which is conserved from C. elegans to humans.
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Affiliation(s)
- Nivedita Chatterjee
- School of Environmental Engineering, Graduate School of Energy and Environmental system Engineering, University of Seoul, 163 Siripdaero, Dongdaemun-gu, Seoul, 130-743, Korea
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44
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Lee AJ, Warshaw DM, Wallace SS. Insights into the glycosylase search for damage from single-molecule fluorescence microscopy. DNA Repair (Amst) 2014; 20:23-31. [PMID: 24560296 DOI: 10.1016/j.dnarep.2014.01.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 12/13/2013] [Accepted: 01/22/2014] [Indexed: 12/21/2022]
Abstract
The first step of base excision repair utilizes glycosylase enzymes to find damage within a genome. A persistent question in the field of DNA repair is how glycosylases interact with DNA to specifically find and excise target damaged bases with high efficiency and specificity. Ensemble studies have indicated that glycosylase enzymes rely upon both sliding and distributive modes of search, but ensemble methods are limited in their ability to directly observe these modes. Here we review insights into glycosylase scanning behavior gathered through single-molecule fluorescence studies of enzyme interactions with DNA and provide a context for these results in relation to ensemble experiments.
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Affiliation(s)
- Andrea J Lee
- Department of Microbiology and Molecular Genetics, The Markey Center for Molecular Genetics, The University of Vermont, 95 Carrigan Drive, Stafford Hall, Burlington, VT 05405-0084, USA.
| | - David M Warshaw
- Department of Molecular Physiology and Biophysics, The University of Vermont, Health Science Research Facility, 149 Beaumont Avenue, Burlington, VT 05405-0075, USA.
| | - Susan S Wallace
- Department of Microbiology and Molecular Genetics, The Markey Center for Molecular Genetics, The University of Vermont, 95 Carrigan Drive, Stafford Hall, Burlington, VT 05405-0084, USA.
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45
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Backe PH, Simm R, Laerdahl JK, Dalhus B, Fagerlund A, Okstad OA, Rognes T, Alseth I, Kolstø AB, Bjørås M. A new family of proteins related to the HEAT-like repeat DNA glycosylases with affinity for branched DNA structures. J Struct Biol 2013; 183:66-75. [PMID: 23623903 DOI: 10.1016/j.jsb.2013.04.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 04/09/2013] [Accepted: 04/16/2013] [Indexed: 12/27/2022]
Abstract
The recently discovered HEAT-like repeat (HLR) DNA glycosylase superfamily is widely distributed in all domains of life. The present bioinformatics and phylogenetic analysis shows that HLR DNA glycosylase superfamily members in the genus Bacillus form three subfamilies: AlkC, AlkD and AlkF/AlkG. The crystal structure of AlkF shows structural similarity with the DNA glycosylases AlkC and AlkD, however neither AlkF nor AlkG display any DNA glycosylase activity. Instead, both proteins have affinity to branched DNA structures such as three-way and Holliday junctions. A unique β-hairpin in the AlkF/AlkG subfamily is most likely inserted into the DNA major groove, and could be a structural determinant regulating DNA substrate affinity. We conclude that AlkF and AlkG represent a new family of HLR proteins with affinity for branched DNA structures.
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Affiliation(s)
- Paul H Backe
- Department of Microbiology, Oslo University Hospital and University of Oslo, P.O. Box 4950 Nydalen, 0424 Oslo, Norway
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46
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Abstract
Maintenance of genetic stability is crucial for all organisms in order to avoid the onset of deleterious diseases such as cancer. One of the many proveniences of DNA base damage in mammalian cells is oxidative stress, arising from a variety of endogenous and exogenous sources, generating highly mutagenic oxidative DNA lesions. One of the best characterized oxidative DNA lesion is 7,8-dihydro-8-oxoguanine (8-oxo-G), which can give rise to base substitution mutations (also known as point mutations). This mutagenicity is due to the miscoding potential of 8-oxo-G that instructs most DNA polymerases (pols) to preferentially insert an Adenine (A) opposite 8-oxo-G instead of the appropriate Cytosine (C). If left unrepaired, such A:8-oxo-G mispairs can give rise to CG→AT transversion mutations. A:8-oxo-G mispairs are proficiently recognized by the MutY glycosylase homologue (MUTYH). MUTYH can remove the mispaired A from an A:8-oxo-G, giving way to the canonical base-excision repair (BER) that ultimately restores undamaged Guanine (G). The importance of this MUTYH-initiated pathway is illustrated by the fact that biallelic mutations in the MUTYH gene are associated with a hereditary colorectal cancer syndrome termed MUTYH-associated polyposis (MAP). In this review, we will focus on MUTYH, from its discovery to the most recent data regarding its cellular roles and interaction partners. We discuss the involvement of the MUTYH protein in the A:8-oxo-G BER pathway acting together with pol λ, the pol that can faithfully incorporate C opposite 8-oxo-G and thus bypass this lesion in a correct manner. We also outline the current knowledge about the regulation of MUTYH itself and the A:8-oxo-G repair pathway by posttranslational modifications (PTM). Finally, to achieve a clearer overview of the literature, we will briefly touch on the rather confusing MUTYH nomenclature. In short, MUTYH is a unique DNA glycosylase that catalyzes the excision of an undamaged base from DNA.
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Affiliation(s)
- Enni Markkanen
- Institute for Veterinary Biochemistry and Molecular Biology, University of Zürich-Irchel Zürich, Switzerland
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