1
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Ferenc K, Marcinkowski M, Olszewski J, Kowalczyk P, Pilžys T, Garbicz D, Dib N, Świderska B, Matyba P, Gajewski Z, Grzesiuk E, Zabielski R. The proteomic profile is altered but not repaired after bariatric surgery in type 2 diabetes pigs. Sci Rep 2024; 14:10235. [PMID: 38702370 PMCID: PMC11068747 DOI: 10.1038/s41598-024-60022-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 04/17/2024] [Indexed: 05/06/2024] Open
Abstract
To reveal the sources of obesity and type 2 diabetes (T2D) in humans, animal models, mainly rodents, have been used. Here, we propose a pig model of T2D. Weaned piglets were fed high fat/high sugar diet suppling 150% of metabolizable energy. Measurements of weight gain, blood morphology, glucose plasma levels, cholesterol, and triglycerides, as well as glucose tolerance (oral glucose tolerance test, OGTT) were employed to observe T2D development. The histology and mass spectrometry analyses were made post mortem. Within 6 months, the high fat-high sugar (HFHS) fed pigs showed gradual and significant increase in plasma triglycerides and glucose levels in comparison to the controls. Using OGTT test, we found stable glucose intolerance in 10 out of 14 HFHS pigs. Mass spectrometry analysis indicated significant changes in 330 proteins in the intestine, liver, and pancreas of the HFHS pigs. These pigs showed also an increase in DNA base modifications and elevated level of the ALKBH proteins in the tissues. Six diabetic HFHS pigs underwent Scopinaro bariatric surgery restoring glycaemia one month after surgery. In conclusion, a high energy diet applied to piglets resulted in the development of hyperlipidaemia, hyperglycaemia, and type 2 diabetes being reversed by a bariatric procedure, excluding the proteomic profile utill one month after the surgery.
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Affiliation(s)
- Karolina Ferenc
- Center for Translational Medicine, Warsaw University of Life Sciences, Nowoursynowska 100, 02-797, Warsaw, Poland
| | - Michał Marcinkowski
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Jarosław Olszewski
- Center for Translational Medicine, Warsaw University of Life Sciences, Nowoursynowska 100, 02-797, Warsaw, Poland
| | - Paweł Kowalczyk
- Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Instytucka 3, 05-110, Jabłonna, Poland
| | - Tomaš Pilžys
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Damian Garbicz
- Institute of Oncology, Maria Sklodowska-Curie National Research, W.K. Roentgena 5, 02-781, Warsaw, Poland
| | - Naser Dib
- European Health Centre Otwock (ECZ Otwock), The Fryderyk Chopin Hospital, Borowa 14/18, 05-400, Otwock, Poland
| | - Bianka Świderska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Piotr Matyba
- Center for Translational Medicine, Warsaw University of Life Sciences, Nowoursynowska 100, 02-797, Warsaw, Poland
| | - Zdzisław Gajewski
- Center for Translational Medicine, Warsaw University of Life Sciences, Nowoursynowska 100, 02-797, Warsaw, Poland
| | - Elżbieta Grzesiuk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland.
| | - Romuald Zabielski
- Center for Translational Medicine, Warsaw University of Life Sciences, Nowoursynowska 100, 02-797, Warsaw, Poland.
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2
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Cecerska-Heryć E, Wiśniewska Z, Serwin N, Polikowska A, Goszka M, Engwert W, Michałów J, Pękała M, Budkowska M, Michalczyk A, Dołęgowska B. Can Compounds of Natural Origin Be Important in Chemoprevention? Anticancer Properties of Quercetin, Resveratrol, and Curcumin-A Comprehensive Review. Int J Mol Sci 2024; 25:4505. [PMID: 38674092 PMCID: PMC11050349 DOI: 10.3390/ijms25084505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 04/17/2024] [Accepted: 04/18/2024] [Indexed: 04/28/2024] Open
Abstract
Malignant tumors are the second most common cause of death worldwide. More attention is being paid to the link between the body's impaired oxidoreductive balance and cancer incidence. Much attention is being paid to polyphenols derived from plants, as one of their properties is an antioxidant character: the ability to eliminate reactive oxygen and nitrogen species, chelate specific metal ions, modulate signaling pathways affecting inflammation, and raise the level and activity of antioxidant enzymes while lowering those with oxidative effects. The following three compounds, resveratrol, quercetin, and curcumin, are polyphenols modulating multiple molecular targets, or increasing pro-apoptotic protein expression levels and decreasing anti-apoptotic protein expression levels. Experiments conducted in vitro and in vivo on animals and humans suggest using them as chemopreventive agents based on antioxidant properties. The advantage of these natural polyphenols is low toxicity and weak adverse effects at higher doses. However, the compounds discussed are characterized by low bioavailability and solubility, which may make achieving the blood concentrations needed for the desired effect challenging. The solution may lie in derivatives of naturally occurring polyphenols subjected to structural modifications that enhance their beneficial effects or work on implementing new ways of delivering antioxidants that improve their solubility and bioavailability.
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Affiliation(s)
- Elżbieta Cecerska-Heryć
- Department of Laboratory Medicine, Pomeranian Medical University of Szczecin, Powstancow Wielkopolskich 72, 70-111 Szczecin, Poland; (Z.W.); (N.S.); (A.P.); (M.G.); (W.E.); (J.M.); (M.P.); (B.D.)
| | - Zofia Wiśniewska
- Department of Laboratory Medicine, Pomeranian Medical University of Szczecin, Powstancow Wielkopolskich 72, 70-111 Szczecin, Poland; (Z.W.); (N.S.); (A.P.); (M.G.); (W.E.); (J.M.); (M.P.); (B.D.)
| | - Natalia Serwin
- Department of Laboratory Medicine, Pomeranian Medical University of Szczecin, Powstancow Wielkopolskich 72, 70-111 Szczecin, Poland; (Z.W.); (N.S.); (A.P.); (M.G.); (W.E.); (J.M.); (M.P.); (B.D.)
| | - Aleksandra Polikowska
- Department of Laboratory Medicine, Pomeranian Medical University of Szczecin, Powstancow Wielkopolskich 72, 70-111 Szczecin, Poland; (Z.W.); (N.S.); (A.P.); (M.G.); (W.E.); (J.M.); (M.P.); (B.D.)
| | - Małgorzata Goszka
- Department of Laboratory Medicine, Pomeranian Medical University of Szczecin, Powstancow Wielkopolskich 72, 70-111 Szczecin, Poland; (Z.W.); (N.S.); (A.P.); (M.G.); (W.E.); (J.M.); (M.P.); (B.D.)
| | - Weronika Engwert
- Department of Laboratory Medicine, Pomeranian Medical University of Szczecin, Powstancow Wielkopolskich 72, 70-111 Szczecin, Poland; (Z.W.); (N.S.); (A.P.); (M.G.); (W.E.); (J.M.); (M.P.); (B.D.)
| | - Jaśmina Michałów
- Department of Laboratory Medicine, Pomeranian Medical University of Szczecin, Powstancow Wielkopolskich 72, 70-111 Szczecin, Poland; (Z.W.); (N.S.); (A.P.); (M.G.); (W.E.); (J.M.); (M.P.); (B.D.)
| | - Maja Pękała
- Department of Laboratory Medicine, Pomeranian Medical University of Szczecin, Powstancow Wielkopolskich 72, 70-111 Szczecin, Poland; (Z.W.); (N.S.); (A.P.); (M.G.); (W.E.); (J.M.); (M.P.); (B.D.)
| | - Marta Budkowska
- Department of Medical Analytics, Pomeranian Medical University of Szczecin, Powstancow Wielkopolskich 72, 70-111 Szczecin, Poland;
| | - Anna Michalczyk
- Department of Psychiatry, Pomeranian Medical University of Szczecin, Broniewskiego 26, 71-460 Szczecin, Poland;
| | - Barbara Dołęgowska
- Department of Laboratory Medicine, Pomeranian Medical University of Szczecin, Powstancow Wielkopolskich 72, 70-111 Szczecin, Poland; (Z.W.); (N.S.); (A.P.); (M.G.); (W.E.); (J.M.); (M.P.); (B.D.)
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3
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Davletgildeeva AT, Tyugashev TE, Zhao M, Kuznetsov NA, Ishchenko AA, Saparbaev M, Kuznetsova AA. Individual Contributions of Amido Acid Residues Tyr122, Ile168, and Asp173 to the Activity and Substrate Specificity of Human DNA Dioxygenase ABH2. Cells 2023; 12:1839. [PMID: 37508504 PMCID: PMC10377887 DOI: 10.3390/cells12141839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 06/29/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023] Open
Abstract
Human Fe(II)/α-ketoglutarate-dependent dioxygenase ABH2 plays a crucial role in the direct reversal repair of nonbulky alkyl lesions in DNA nucleobases, e.g., N1-methyladenine (m1A), N3-methylcytosine (m3C), and some etheno derivatives. Moreover, ABH2 is capable of a less efficient oxidation of an epigenetic DNA mark called 5-methylcytosine (m5C), which typically is a specific target of DNA dioxygenases from the TET family. In this study, to elucidate the mechanism of the substrate specificity of ABH2, we investigated the role of several active-site amino acid residues. Functional mapping of the lesion-binding pocket was performed through the analysis of the functions of Tyr122, Ile168, and Asp173 in the damaged base recognition mechanism. Interactions of wild-type ABH2, or its mutants Y122A, I168A, or D173A, with damaged DNA containing the methylated base m1A or m3C or the epigenetic marker m5C were analyzed by molecular dynamics simulations and kinetic assays. Comparative analysis of the enzymes revealed an effect of the substitutions on DNA binding and on catalytic activity. Obtained data clearly demonstrate the effect of the tested amino acid residues on the catalytic activity of the enzymes rather than the DNA-binding ability. Taken together, these data shed light on the molecular and kinetic consequences of the substitution of active-site residues for the mechanism of the substrate recognition.
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Affiliation(s)
- Anastasiia T Davletgildeeva
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Timofey E Tyugashev
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Mingxing Zhao
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Nikita A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Alexander A Ishchenko
- Groupe Mechanisms of DNA Repair and Carcinogenesis, CNRS UMR9019, Gustave Roussy Cancer Campus, Université Paris-Saclay, CEDEX, F-94805 Villejuif, France
| | - Murat Saparbaev
- Groupe Mechanisms of DNA Repair and Carcinogenesis, CNRS UMR9019, Gustave Roussy Cancer Campus, Université Paris-Saclay, CEDEX, F-94805 Villejuif, France
| | - Aleksandra A Kuznetsova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
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4
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Conformational Dynamics of Human ALKBH2 Dioxygenase in the Course of DNA Repair as Revealed by Stopped-Flow Fluorescence Spectroscopy. Molecules 2022; 27:molecules27154960. [PMID: 35956910 PMCID: PMC9370705 DOI: 10.3390/molecules27154960] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/28/2022] [Accepted: 08/01/2022] [Indexed: 11/30/2022] Open
Abstract
Elucidation of physicochemical mechanisms of enzymatic processes is one of the main tasks of modern biology. High efficiency and selectivity of enzymatic catalysis are mostly ensured by conformational dynamics of enzymes and substrates. Here, we applied a stopped-flow kinetic analysis based on fluorescent spectroscopy to investigate mechanisms of conformational transformations during the removal of alkylated bases from DNA by ALKBH2, a human homolog of Escherichia coli AlkB dioxygenase. This enzyme protects genomic DNA against various alkyl lesions through a sophisticated catalytic mechanism supported by a cofactor (Fe(II)), a cosubstrate (2-oxoglutarate), and O2. We present here a comparative study of conformational dynamics in complexes of the ALKBH2 protein with double-stranded DNA substrates containing N1-methyladenine, N3-methylcytosine, or 1,N6-ethenoadenine. By means of fluorescent labels of different types, simultaneous detection of conformational transitions in the protein globule and DNA substrate molecule was performed. Fitting of the kinetic curves by a nonlinear-regression method yielded a molecular mechanism and rate constants of its individual steps. The results shed light on overall conformational dynamics of ALKBH2 and damaged DNA during the catalytic cycle.
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5
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Berger MB, Walker AR, Vázquez-Montelongo EA, Cisneros GA. Computational investigations of selected enzymes from two iron and α-ketoglutarate-dependent families. Phys Chem Chem Phys 2021; 23:22227-22240. [PMID: 34586107 PMCID: PMC8516722 DOI: 10.1039/d1cp03800a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
DNA alkylation is used as the key epigenetic mark in eukaryotes, however, most alkylation in DNA can result in deleterious effects. Therefore, this process needs to be tightly regulated. The enzymes of the AlkB and Ten-Eleven Translocation (TET) families are members of the Fe and alpha-ketoglutarate-dependent superfamily of enzymes that are tasked with dealkylating DNA and RNA in cells. Members of these families span all species and are an integral part of transcriptional regulation. While both families catalyze oxidative dealkylation of various bases, each has specific preference for alkylated base type as well as distinct catalytic mechanisms. This perspective aims to provide an overview of computational work carried out to investigate several members of these enzyme families including AlkB, ALKB Homolog 2, ALKB Homolog 3 and Ten-Eleven Translocate 2. Insights into structural details, mutagenesis studies, reaction path analysis, electronic structure features in the active site, and substrate preferences are presented and discussed.
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Affiliation(s)
- Madison B Berger
- Department of Chemistry, University of North Texas, Denton, Texas, 76201, USA.
| | - Alice R Walker
- Department of Chemistry, Wayne State University, Detroit, Michigan, 48202, USA
| | | | - G Andrés Cisneros
- Department of Chemistry, University of North Texas, Denton, Texas, 76201, USA.
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6
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DNA Demethylation in the Processes of Repair and Epigenetic Regulation Performed by 2-Ketoglutarate-Dependent DNA Dioxygenases. Int J Mol Sci 2021; 22:ijms221910540. [PMID: 34638881 PMCID: PMC8508711 DOI: 10.3390/ijms221910540] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 09/26/2021] [Accepted: 09/27/2021] [Indexed: 12/05/2022] Open
Abstract
Site-specific DNA methylation plays an important role in epigenetic regulation of gene expression. Chemical methylation of DNA, including the formation of various methylated nitrogenous bases, leads to the formation of genotoxic modifications that impair DNA functions. Despite the fact that different pathways give rise to methyl groups in DNA, the main pathway for their removal is oxidative demethylation, which is catalyzed by nonheme Fe(II)/α-ketoglutarate–dependent DNA dioxygenases. DNA dioxygenases share a common catalytic mechanism of the oxidation of the alkyl groups on nitrogenous bases in nucleic acids. This review presents generalized data on the catalytic mechanism of action of DNA dioxygenases and on the participation of typical representatives of this superfamily, such as prokaryotic enzyme AlkB and eukaryotic enzymes ALKBH1–8 and TET1–3, in both processes of direct repair of alkylated DNA adducts and in the removal of an epigenetic mark (5-methylcytosine).
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7
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Epigenetic loss of m1A RNA demethylase ALKBH3 in Hodgkin lymphoma targets collagen, conferring poor clinical outcome. Blood 2021; 137:994-999. [PMID: 32915956 DOI: 10.1182/blood.2020005823] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 08/26/2020] [Indexed: 12/28/2022] Open
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8
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Reversal of nucleobase methylation by dioxygenases. Nat Chem Biol 2020; 16:1160-1169. [DOI: 10.1038/s41589-020-00675-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Accepted: 09/11/2020] [Indexed: 12/12/2022]
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9
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Lenz SAP, Li D, Wetmore SD. Insights into the Direct Oxidative Repair of Etheno Lesions: MD and QM/MM Study on the Substrate Scope of ALKBH2 and AlkB. DNA Repair (Amst) 2020; 96:102944. [PMID: 33161373 DOI: 10.1016/j.dnarep.2020.102944] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/27/2020] [Accepted: 07/30/2020] [Indexed: 01/09/2023]
Abstract
E. coli AlkB and human ALKBH2 belong to the AlkB family enzymes, which contain several α-ketoglutarate (α-KG)/Fe(II)-dependent dioxygenases that repair alkylated DNA. Specifically, the AlkB enzymes catalyze decarboxylation of α-KG to generate a high-valent Fe(IV)-oxo species that oxidizes alkyl groups on DNA adducts. AlkB and ALKBH2 have been reported to differentially repair select etheno adducts, with preferences for 1,N6-ethenoadenine (1,N6-εA) and 3,N4-ethenocytosine (3,N4-εC) over 1,N2-ethenoguanine (1,N2-εG). However, N2,3-ethenoguanine (N2,3-εG), the most common etheno adduct, is not repaired by the AlkB enzymes. Unfortunately, a structural understanding of the differential activity of E. coli AlkB and human ALKBH2 is lacking due to challenges acquiring atomistic details for a range of substrates using experiments. This study uses both molecular dynamics (MD) simulations and ONIOM(QM:MM) calculations to determine how the active site changes upon binding each etheno adduct and characterizes the corresponding catalytic impacts. Our data reveal that the preferred etheno substrates (1,N6-εA and 3,N4-εC) form favorable interactions with catalytic residues that situate the lesion near the Fe(IV)-oxo species and permit efficient oxidation. In contrast, although the damage remains correctly aligned with respect to the Fe(IV)-oxo moiety, repair of 1,N2-εG is mitigated by increased solvation of the active site and a larger distance between Fe(IV)-oxo and the aberrant carbons. Binding of non-substrate N2,3-εG in the active site disrupts key DNA-enzyme interactions, and positions the aberrant carbon atoms even further from the Fe(IV)-oxo species, leading to prohibitively high barriers for oxidative catalysis. Overall, our calculations provide the first structural insight required to rationalize the experimentally-reported substrate specificities of AlkB and ALKBH2 and thereby highlight the roles of several active site residues in the repair of etheno adducts that directly correlates with available experimental data. These proposed catalytic strategies can likely be generalized to other α-KG/Fe(II)-dependent dioxygenases that play similar critical biological roles, including epigenetic and post-translational regulation.
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Affiliation(s)
- Stefan A P Lenz
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta, T1K 3M4, Canada
| | - Deyu Li
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, 02881, USA
| | - Stacey D Wetmore
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta, T1K 3M4, Canada.
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10
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Baldwin MR, Admiraal SJ, O'Brien PJ. Transient kinetic analysis of oxidative dealkylation by the direct reversal DNA repair enzyme AlkB. J Biol Chem 2020; 295:7317-7326. [PMID: 32284330 PMCID: PMC7247310 DOI: 10.1074/jbc.ra120.013517] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 04/10/2020] [Indexed: 11/06/2022] Open
Abstract
AlkB is a bacterial Fe(II)- and 2-oxoglutarate-dependent dioxygenase that repairs a wide range of alkylated nucleobases in DNA and RNA as part of the adaptive response to exogenous nucleic acid-alkylating agents. Although there has been longstanding interest in the structure and specificity of Escherichia coli AlkB and its homologs, difficulties in assaying their repair activities have limited our understanding of their substrate specificities and kinetic mechanisms. Here, we used quantitative kinetic approaches to determine the transient kinetics of recognition and repair of alkylated DNA by AlkB. These experiments revealed that AlkB is a much faster alkylation repair enzyme than previously reported and that it is significantly faster than DNA repair glycosylases that recognize and excise some of the same base lesions. We observed that whereas 1,N6-ethenoadenine can be repaired by AlkB with similar efficiencies in both single- and double-stranded DNA, 1-methyladenine is preferentially repaired in single-stranded DNA. Our results lay the groundwork for future studies of AlkB and its human homologs ALKBH2 and ALKBH3.
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Affiliation(s)
- Michael R Baldwin
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
| | - Suzanne J Admiraal
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
| | - Patrick J O'Brien
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600.
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11
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Marcinkowski M, Pilžys T, Garbicz D, Steciuk J, Zugaj D, Mielecki D, Sarnowski TJ, Grzesiuk E. Human and Arabidopsis alpha-ketoglutarate-dependent dioxygenase homolog proteins-New players in important regulatory processes. IUBMB Life 2020; 72:1126-1144. [PMID: 32207231 DOI: 10.1002/iub.2276] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 02/20/2020] [Accepted: 03/08/2020] [Indexed: 12/31/2022]
Abstract
The family of AlkB homolog (ALKBH) proteins, the homologs of Escherichia coli AlkB 2-oxoglutarate (2OG), and Fe(II)-dependent dioxygenase are involved in a number of important regulatory processes in eukaryotic cells including repair of alkylation lesions in DNA, RNA, and nucleoprotein complexes. There are nine human and thirteen Arabidopsis thaliana ALKBH proteins described, which exhibit diversified functions. Among them, human ALKBH5 and FaT mass and Obesity-associated (FTO) protein and Arabidopsis ALKBH9B and ALKBH10B have been recognized as N6 methyladenine (N6 meA) demethylases, the most abundant posttranscriptional modification in mRNA. The FTO protein is reported to be associated with obesity and type 2 diabetes, and involved in multiple other processes, while ALKBH5 is induced by hypoxia. Arabidopsis ALKBH9B is an N6 meA demethylase influencing plant susceptibility to viral infections via m6 A/A ratio control in viral RNA. ALKBH10B has been discovered to be a functional Arabidopsis homolog of FTO; thus, it is also an RNA N6 meA demethylase involved in plant flowering and several other regulatory processes including control of metabolism. High-throughput mass spectrometry showed multiple sites of human ALKBH phosphorylation. In the case of FTO, the type of modified residue decides about the further processing of the protein. This modification may result in subsequent protein ubiquitination and proteolysis, or in the blocking of these processes. However, the impact of phosphorylation on the other ALKBH function and their downstream pathways remains nearly unexplored in both human and Arabidopsis. Therefore, the investigation of evolutionarily conserved functions of ALKBH proteins and their regulatory impact on important cellular processes is clearly called for.
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Affiliation(s)
- Michał Marcinkowski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Tomaš Pilžys
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Damian Garbicz
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Jaroslaw Steciuk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Dorota Zugaj
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Damian Mielecki
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Tomasz J Sarnowski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Elżbieta Grzesiuk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
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12
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Koliadenko V, Wilanowski T. Additional functions of selected proteins involved in DNA repair. Free Radic Biol Med 2020; 146:1-15. [PMID: 31639437 DOI: 10.1016/j.freeradbiomed.2019.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 10/16/2019] [Accepted: 10/16/2019] [Indexed: 12/30/2022]
Abstract
Protein moonlighting is a phenomenon in which a single polypeptide chain can perform a number of different unrelated functions. Here we present our analysis of moonlighting in the case of selected DNA repair proteins which include G:T mismatch-specific thymine DNA glycosylase (TDG), methyl-CpG-binding domain protein 4 (MBD4), apurinic/apyrimidinic endonuclease 1 (APE1), AlkB homologs, poly (ADP-ribose) polymerase 1 (PARP-1) and single-strand selective monofunctional uracil DNA glycosylase 1 (SMUG1). Most of their additional functions are not accidental and clear patterns are emerging. Participation in RNA metabolism is not surprising as bases occurring in RNA are the same or very similar to those in DNA. Other common additional function involves regulation of transcription. This is not unexpected as these proteins bind to specific DNA regions for DNA repair, hence they can also be recruited to regulate transcription. Participation in demethylation and replication of DNA appears logical as well. Some of the multifunctional DNA repair proteins play major roles in many diseases, including cancer. However, their moonlighting might prove a major difficulty in the development of new therapies because it will not be trivial to target a single protein function without affecting its other functions that are not related to the disease.
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Affiliation(s)
- Vlada Koliadenko
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Ilji Miecznikowa 1, 02-096, Warsaw, Poland
| | - Tomasz Wilanowski
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Ilji Miecznikowa 1, 02-096, Warsaw, Poland.
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13
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Kay J, Thadhani E, Samson L, Engelward B. Inflammation-induced DNA damage, mutations and cancer. DNA Repair (Amst) 2019; 83:102673. [PMID: 31387777 DOI: 10.1016/j.dnarep.2019.102673] [Citation(s) in RCA: 199] [Impact Index Per Article: 39.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 06/15/2019] [Accepted: 07/18/2019] [Indexed: 12/22/2022]
Abstract
The relationships between inflammation and cancer are varied and complex. An important connection linking inflammation to cancer development is DNA damage. During inflammation reactive oxygen and nitrogen species (RONS) are created to combat pathogens and to stimulate tissue repair and regeneration, but these chemicals can also damage DNA, which in turn can promote mutations that initiate and promote cancer. DNA repair pathways are essential for preventing DNA damage from causing mutations and cytotoxicity, but RONS can interfere with repair mechanisms, reducing their efficacy. Further, cellular responses to DNA damage, such as damage signaling and cytotoxicity, can promote inflammation, creating a positive feedback loop. Despite coordination of DNA repair and oxidative stress responses, there are nevertheless examples whereby inflammation has been shown to promote mutagenesis, tissue damage, and ultimately carcinogenesis. Here, we discuss the DNA damage-mediated associations between inflammation, mutagenesis and cancer.
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Affiliation(s)
- Jennifer Kay
- Department of Biological Engineering, United States.
| | | | - Leona Samson
- Department of Biological Engineering, United States; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, 02139, United States
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14
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In vivo measurements of interindividual differences in DNA glycosylases and APE1 activities. Proc Natl Acad Sci U S A 2017; 114:E10379-E10388. [PMID: 29122935 DOI: 10.1073/pnas.1712032114] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The integrity of our DNA is challenged with at least 100,000 lesions per cell on a daily basis. Failure to repair DNA damage efficiently can lead to cancer, immunodeficiency, and neurodegenerative disease. Base excision repair (BER) recognizes and repairs minimally helix-distorting DNA base lesions induced by both endogenous and exogenous DNA damaging agents. Levels of BER-initiating DNA glycosylases can vary between individuals, suggesting that quantitating and understanding interindividual differences in DNA repair capacity (DRC) may enable us to predict and prevent disease in a personalized manner. However, population studies of BER capacity have been limited because most methods used to measure BER activity are cumbersome, time consuming and, for the most part, only allow for the analysis of one DNA glycosylase at a time. We have developed a fluorescence-based multiplex flow-cytometric host cell reactivation assay wherein the activity of several enzymes [four BER-initiating DNA glycosylases and the downstream processing apurinic/apyrimidinic endonuclease 1 (APE1)] can be tested simultaneously, at single-cell resolution, in vivo. Taking advantage of the transcriptional properties of several DNA lesions, we have engineered specific fluorescent reporter plasmids for quantitative measurements of 8-oxoguanine DNA glycosylase, alkyl-adenine DNA glycosylase, MutY DNA glycosylase, uracil DNA glycosylase, and APE1 activity. We have used these reporters to measure differences in BER capacity across a panel of cell lines collected from healthy individuals, and to generate mathematical models that predict cellular sensitivity to methylmethane sulfonate, H2O2, and 5-FU from DRC. Moreover, we demonstrate the suitability of these reporters to measure differences in DRC in multiple pathways using primary lymphocytes from two individuals.
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15
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Chaim IA, Gardner A, Wu J, Iyama T, Wilson DM, Samson LD. A novel role for transcription-coupled nucleotide excision repair for the in vivo repair of 3,N4-ethenocytosine. Nucleic Acids Res 2017; 45:3242-3252. [PMID: 28115629 PMCID: PMC5389632 DOI: 10.1093/nar/gkx015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 01/20/2017] [Indexed: 12/13/2022] Open
Abstract
Etheno (ε) DNA base adducts are highly mutagenic lesions produced endogenously via reactions with lipid peroxidation (LPO) products. Cancer-promoting conditions, such as inflammation, can induce persistent oxidative stress and increased LPO, resulting in the accumulation of ε-adducts in different tissues. Using a recently described fluorescence multiplexed host cell reactivation assay, we show that a plasmid reporter bearing a site-specific 3,N4-ethenocytosine (εC) causes transcriptional blockage. Notably, this blockage is exacerbated in Cockayne Syndrome and xeroderma pigmentosum patient-derived lymphoblastoid and fibroblast cells. Parallel RNA-Seq expression analysis of the plasmid reporter identifies novel transcriptional mutagenesis properties of εC. Our studies reveal that beyond the known pathways, such as base excision repair, the process of transcription-coupled nucleotide excision repair plays a role in the removal of εC from the genome, and thus in the protection of cells and tissues from collateral damage induced by inflammatory responses.
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Affiliation(s)
- Isaac A Chaim
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Alycia Gardner
- Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jie Wu
- The Barbara K. Ostrom (1978) Bioinformatics and Computing Facility in the Swanson Biotechnology Center, Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Teruaki Iyama
- Laboratory of Molecular Gerontology, National Institute on Aging, Intramural Research Program, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - David M Wilson
- Laboratory of Molecular Gerontology, National Institute on Aging, Intramural Research Program, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Leona D Samson
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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16
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Tudek B, Zdżalik-Bielecka D, Tudek A, Kosicki K, Fabisiewicz A, Speina E. Lipid peroxidation in face of DNA damage, DNA repair and other cellular processes. Free Radic Biol Med 2017; 107:77-89. [PMID: 27908783 DOI: 10.1016/j.freeradbiomed.2016.11.043] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 11/20/2016] [Accepted: 11/27/2016] [Indexed: 01/09/2023]
Abstract
Exocyclic adducts to DNA bases are formed as a consequence of exposure to certain environmental carcinogens as well as inflammation and lipid peroxidation (LPO). Complex family of LPO products gives rise to a variety of DNA adducts, which can be grouped in two classes: (i) small etheno-type adducts of strong mutagenic potential, and (ii) bulky, propano-type adducts, which block replication and transcription, and are lethal lesions. Etheno-DNA adducts are removed from the DNA by base excision repair (BER), AlkB and nucleotide incision repair enzymes (NIR), while substituted propano-type lesions by nucleotide excision repair (NER) and homologous recombination (HR). Changes of the level and activity of several enzymes removing exocyclic adducts from the DNA was reported during carcinogenesis. Also several beyond repair functions of these enzymes, which participate in regulation of cell proliferation and growth, as well as RNA processing was recently described. In addition, adducts of LPO products to proteins was reported during aging and age-related diseases. The paper summarizes pathways for exocyclic adducts removal and describes how proteins involved in repair of these adducts can modify pathological states of the organism.
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Affiliation(s)
- Barbara Tudek
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland; Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
| | - Daria Zdżalik-Bielecka
- Laboratory of Cell Biology, International Institute of Molecular and Cell Biology, Ksiecia Trojdena 4, 02-109 Warsaw, Poland
| | - Agnieszka Tudek
- Department of Molecular Biology and Genetics, Aarhus University, C. F. Mollers Alle 3, 8000 Aarhus, Denmark
| | - Konrad Kosicki
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
| | - Anna Fabisiewicz
- Department of Molecular and Translational Oncology, Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Roentgena 5, Warsaw 02-781, Poland
| | - Elżbieta Speina
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland
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Hendershot JM, O'Brien PJ. Transient Kinetic Methods for Mechanistic Characterization of DNA Binding and Nucleotide Flipping. Methods Enzymol 2017; 592:377-415. [PMID: 28668128 DOI: 10.1016/bs.mie.2017.04.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Enzymes that modify nucleobases in double-stranded genomic DNA, either as part of a DNA repair pathway or as an epigenetic modifying pathway, adopt a multistep pathway to locate target sites and reconfigure the DNA to gain access. Work on several different enzymes has shown that in almost all cases base flipping, also known as nucleotide flipping, is a key feature of specific site recognition. In this chapter, we discuss some of the strategies that can be used to perform a kinetic characterization for DNA binding and nucleotide flipping. The resulting kinetic and thermodynamic framework provides a platform for understanding substrate specificity, mechanisms of inhibition, and the roles of important amino acids. We use a human DNA repair glycosylase called alkyladenine DNA glycosylase as a case study, because this is one of the best-characterized nucleotide-flipping enzymes. However, the approaches that are described can be readily adapted to study other enzymes, and future studies are needed to understand the mechanism of substrate recognition in each individual case. As more enzymes are characterized, we can hope to uncover which features of DNA searching and nucleotide flipping are fundamental features shared by many different families of DNA modifying enzymes, and which features are specific to a particular enzyme. Such an understanding provides reasonable models for less characterized enzymes that are important for epigenetic DNA modification and DNA repair pathways.
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Affiliation(s)
| | - Patrick J O'Brien
- University of Michigan Medical School, Ann Arbor, MI, United States.
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18
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Gao L, Mutlu E, Collins LB, Walker NJ, Hartwell HJ, Olson JR, Sun W, Gold A, Ball LM, Swenberg JA. DNA Product Formation in Female Sprague-Dawley Rats Following Polyhalogenated Aromatic Hydrocarbon (PHAH) Exposure. Chem Res Toxicol 2017; 30:794-803. [PMID: 28207250 PMCID: PMC5363288 DOI: 10.1021/acs.chemrestox.6b00368] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Indexed: 01/16/2023]
Abstract
DNA oxidation damage has been regarded as one of the possible mechanisms for the hepatic carcinogenesis of dioxin-like compounds (DLCs). In this study, we evaluated the toxic equivalency factor (TEF) from the standpoint of induced DNA oxidation products and their relationship to toxicity and carcinogenicity. Nine DNA oxidation products were analyzed in the liver of female Sprague-Dawley rats exposed to 2,3,7,8-tetrachlorodibenzo-pdioxin (TCDD) alone or the tertiary mixture of TCDD, 3,3',4,4',5-pentachlorobiphenyl (PCB 126), and 2,3,4,7,8-pentachlorodibenzofuran (PeCDF) by gavage for 14, 31, and 53 weeks (5 days/week) by LC-MS/MS: 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dGuo); 1,N6-etheno-2'-deoxyadenosine (1,N6-εdAdo); N2,3-ethenoguanine (N2,3-εG); 7-(2-oxoethly)guanine (7-OEG); 1,N2-etheno-2'-deoxyguanosine (1,N2-εdGuo); malondialdehyde (M1dGuo); acrolein (AcrdGuo); crotonaldehyde (CrdGuo); and 4-hydroxynonenal (HNEdGuo) derived 2'-deoxyguanosine adducts. Exposure to TCDD (100 ng/kg/day) significantly induced 1,N6-εdAdo at 31 and 53 weeks, while no increase of 8-oxo-dGuo was observed. Significant increases were observed for 8-oxo-dGuo and 1,N6-εdAdo at all time points following exposure to the tertiary mixture (TEQ 100 ng/kg/day). Exposure to TCDD for 53 weeks only significantly increased 1,N6-εdAdo, while increases of N2,3-εG and 7-OEG were only found in the highest dose group (100 ng/kg/day). Exposure to the tertiary mixture for 53 weeks had no effect on N2,3-εG in any exposure group (TEQ 0, 22, 46, or 100 ng/kg/day), while significant increases were observed for 1,N6-εdAdo (all dose groups), 8-oxo-dGuo (46 and 100 ng/kg/day), and 7-OEG (100 ng/kg/day). While no significant increase was observed at 53 weeks for 1,N2-εdGuo, M1dGuo, AcrdGuo, or CrdGuo following exposure to TCDD (100 ng/kg/day), all of them were significantly induced in animals exposed to the tertiary mixture (TEQ 100 ng/kg/day). This oxidation DNA product data suggest that the simple TEF methodology cannot be applied to evaluate the diverse patterns of toxic effects induced by DLCs.
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Affiliation(s)
- Lina Gao
- Department of Environmental Sciences and Engineering and Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Esra Mutlu
- National
Toxicology Program, National Institute of
Environmental Health Sciences, NIH, RTP, Durham, North Carolina 27709, United States
| | - Leonard B. Collins
- Department of Environmental Sciences and Engineering and Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Nigel J. Walker
- National
Toxicology Program, National Institute of
Environmental Health Sciences, NIH, RTP, Durham, North Carolina 27709, United States
| | - Hadley J. Hartwell
- Department of Environmental Sciences and Engineering and Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - James R. Olson
- Department
of Pharmacology and Toxicology, State University
of New York at Buffalo, Buffalo, New York 14214, United States
| | - Wei Sun
- Department of Environmental Sciences and Engineering and Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Avram Gold
- Department of Environmental Sciences and Engineering and Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Louise M. Ball
- Department of Environmental Sciences and Engineering and Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - James A. Swenberg
- Department of Environmental Sciences and Engineering and Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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19
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Zhang L, Reyes A, Wang X. The Role of DNA Repair in Maintaining Mitochondrial DNA Stability. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1038:85-105. [PMID: 29178071 DOI: 10.1007/978-981-10-6674-0_7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Mitochondria are vital double-membrane organelles that act as a "powerhouse" inside the cell and have essential roles to maintain cellular functions, e.g., ATP production, iron-sulfur synthesis metabolism, and steroid synthesis. An important difference with other organelles is that they contain their own mitochondrial DNA (mtDNA). Such powerful organelles are also sensitive to both endogenous and exogenous factors that can cause lesions to their structural components and their mtDNA, resulting in gene mutations and eventually leading to diseases. In this review, we will mainly focus on mammalian mitochondrial DNA repair pathways that safeguard mitochondrial DNA integrity and several important factors involved in the repair process, especially on an essential pathway, base excision repair. We eagerly anticipate to explore more methods to treat related diseases by constantly groping for these complexes and precise repair mechanisms.
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Affiliation(s)
- Linlin Zhang
- Zhongshan Hospital Institute of Clinical Science, Fudan University, Shanghai Medical College, Shanghai, China.
| | - Aurelio Reyes
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK.
| | - Xiangdong Wang
- Zhongshan Hospital Institute of Clinical Science, Fudan University, Shanghai Medical College, Shanghai, China.
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20
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Bauer NC, Corbett AH, Doetsch PW. The current state of eukaryotic DNA base damage and repair. Nucleic Acids Res 2015; 43:10083-101. [PMID: 26519467 PMCID: PMC4666366 DOI: 10.1093/nar/gkv1136] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 10/16/2015] [Indexed: 12/15/2022] Open
Abstract
DNA damage is a natural hazard of life. The most common DNA lesions are base, sugar, and single-strand break damage resulting from oxidation, alkylation, deamination, and spontaneous hydrolysis. If left unrepaired, such lesions can become fixed in the genome as permanent mutations. Thus, evolution has led to the creation of several highly conserved, partially redundant pathways to repair or mitigate the effects of DNA base damage. The biochemical mechanisms of these pathways have been well characterized and the impact of this work was recently highlighted by the selection of Tomas Lindahl, Aziz Sancar and Paul Modrich as the recipients of the 2015 Nobel Prize in Chemistry for their seminal work in defining DNA repair pathways. However, how these repair pathways are regulated and interconnected is still being elucidated. This review focuses on the classical base excision repair and strand incision pathways in eukaryotes, considering both Saccharomyces cerevisiae and humans, and extends to some important questions and challenges facing the field of DNA base damage repair.
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Affiliation(s)
- Nicholas C Bauer
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Anita H Corbett
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Paul W Doetsch
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA 30322, USA Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA 30322, USA Department of Hematology and Medical Oncology, Emory University School of Medicine, Atlanta, GA 30322, USA
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21
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Reverendo M, Soares AR, Pereira PM, Carreto L, Ferreira V, Gatti E, Pierre P, Moura GR, Santos MA. TRNA mutations that affect decoding fidelity deregulate development and the proteostasis network in zebrafish. RNA Biol 2015; 11:1199-213. [PMID: 25483040 DOI: 10.4161/rna.32199] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Mutations in genes that encode tRNAs, aminoacyl-tRNA syntheases, tRNA modifying enzymes and other tRNA interacting partners are associated with neuropathies, cancer, type-II diabetes and hearing loss, but how these mutations cause disease is unclear. We have hypothesized that levels of tRNA decoding error (mistranslation) that do not fully impair embryonic development can accelerate cell degeneration through proteome instability and saturation of the proteostasis network. To test this hypothesis we have induced mistranslation in zebrafish embryos using mutant tRNAs that misincorporate Serine (Ser) at various non-cognate codon sites. Embryo viability was affected and malformations were observed, but a significant proportion of embryos survived by activating the unfolded protein response (UPR), the ubiquitin proteasome pathway (UPP) and downregulating protein biosynthesis. Accumulation of reactive oxygen species (ROS), mitochondrial and nuclear DNA damage and disruption of the mitochondrial network, were also observed, suggesting that mistranslation had a strong negative impact on protein synthesis rate, ER and mitochondrial homeostasis. We postulate that mistranslation promotes gradual cellular degeneration and disease through protein aggregation, mitochondrial dysfunction and genome instability.
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22
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Zdżalik D, Domańska A, Prorok P, Kosicki K, van den Born E, Falnes PØ, Rizzo CJ, Guengerich FP, Tudek B. Differential repair of etheno-DNA adducts by bacterial and human AlkB proteins. DNA Repair (Amst) 2015; 30:1-10. [PMID: 25797601 PMCID: PMC4451939 DOI: 10.1016/j.dnarep.2015.02.021] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Revised: 02/17/2015] [Accepted: 02/25/2015] [Indexed: 11/16/2022]
Abstract
AlkB proteins are evolutionary conserved Fe(II)/2-oxoglutarate-dependent dioxygenases, which remove alkyl and highly promutagenic etheno(ɛ)-DNA adducts, but their substrate specificity has not been fully determined. We developed a novel assay for the repair of ɛ-adducts by AlkB enzymes using oligodeoxynucleotides with a single lesion and specific DNA glycosylases and AP-endonuclease for identification of the repair products. We compared the repair of three ɛ-adducts, 1,N(6)-ethenoadenine (ɛA), 3,N(4)-ethenocytosine (ɛC) and 1,N(2)-ethenoguanine (1,N(2)-ɛG) by nine bacterial and two human AlkBs, representing four different structural groups defined on the basis of conserved amino acids in the nucleotide recognition lid, engaged in the enzyme binding to the substrate. Two bacterial AlkB proteins, MT-2B (from Mycobacterium tuberculosis) and SC-2B (Streptomyces coelicolor) did not repair these lesions in either double-stranded (ds) or single-stranded (ss) DNA. Three proteins, RE-2A (Rhizobium etli), SA-2B (Streptomyces avermitilis), and XC-2B (Xanthomonas campestris) efficiently removed all three lesions from the DNA substrates. Interestingly, XC-2B and RE-2A are the first AlkB proteins shown to be specialized for ɛ-adducts, since they do not repair methylated bases. Three other proteins, EcAlkB (Escherichia coli), SA-1A, and XC-1B removed ɛA and ɛC from ds and ssDNA but were inactive toward 1,N(2)-ɛG. SC-1A repaired only ɛA with the preference for dsDNA. The human enzyme ALKBH2 repaired all three ɛ-adducts in dsDNA, while only ɛA and ɛC in ssDNA and repair was less efficient in ssDNA. ALKBH3 repaired only ɛC in ssDNA. Altogether, we have shown for the first time that some AlkB proteins, namely ALKBH2, RE-2A, SA-2B and XC-2B can repair 1,N(2)-ɛG and that ALKBH3 removes only ɛC from ssDNA. Our results also suggest that the nucleotide recognition lid is not the sole determinant of the substrate specificity of AlkB proteins.
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Affiliation(s)
- Daria Zdżalik
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Anna Domańska
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw, Poland; Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Paulina Prorok
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Konrad Kosicki
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | | | - Pål Ø Falnes
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Carmelo J Rizzo
- Department of Chemistry, Center in Molecular Toxicology, and Vanderbilt Ingram Cancer Center, Vanderbilt University, Nashville, TN, USA
| | - F Peter Guengerich
- Department of Biochemistry, Center in Molecular Toxicology, and Vanderbilt Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Barbara Tudek
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw, Poland; Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.
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23
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Ougland R, Rognes T, Klungland A, Larsen E. Non-homologous functions of the AlkB homologs. J Mol Cell Biol 2015; 7:494-504. [PMID: 26003568 DOI: 10.1093/jmcb/mjv029] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 02/26/2015] [Indexed: 12/22/2022] Open
Abstract
The DNA repair enzyme AlkB was identified in E. coli more than three decades ago. Since then, nine mammalian homologs, all members of the superfamily of alpha-ketoglutarate and Fe(II)-dependent dioxygenases, have been identified (designated ALKBH1-8 and FTO). While E. coli AlkB serves as a DNA repair enzyme, only two mammalian homologs have been confirmed to repair DNA in vivo. The other mammalian homologs have remarkably diverse substrate specificities and biological functions. Substrates recognized by the different AlkB homologs comprise erroneous methyl- and etheno adducts in DNA, unique wobble uridine modifications in certain tRNAs, methylated adenines in mRNA, and methylated lysines on proteins. The phenotypes of organisms lacking or overexpressing individual AlkB homologs include obesity, severe sensitivity to inflammation, infertility, growth retardation, and multiple malformations. Here we review the present knowledge of the mammalian AlkB homologs and their implications for human disease and development.
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Affiliation(s)
- Rune Ougland
- Clinic for Diagnostics and Intervention and Institute of Medical Microbiology, Oslo University Hospital, Rikshospitalet, 0027 Oslo, Norway Department of Anesthesiology, Division of Emergencies and Critical Care, Oslo University Hospital, The Norwegian Radium Hospital, 0310 Oslo, Norway
| | - Torbjørn Rognes
- Clinic for Diagnostics and Intervention and Institute of Medical Microbiology, Oslo University Hospital, Rikshospitalet, 0027 Oslo, Norway Department of Informatics, University of Oslo, 0316 Oslo, Norway
| | - Arne Klungland
- Clinic for Diagnostics and Intervention and Institute of Medical Microbiology, Oslo University Hospital, Rikshospitalet, 0027 Oslo, Norway Faculty of Medicine, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway
| | - Elisabeth Larsen
- Clinic for Diagnostics and Intervention and Institute of Medical Microbiology, Oslo University Hospital, Rikshospitalet, 0027 Oslo, Norway
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24
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Müller TA, Hausinger RP. AlkB and Its Homologues – DNA Repair and Beyond. 2-OXOGLUTARATE-DEPENDENT OXYGENASES 2015. [DOI: 10.1039/9781782621959-00246] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
AlkB is an Fe(ii)/2-oxoglutarate-dependent dioxygenase that is part of the adaptive response to alkylating agents in Escherichia coli. AlkB hydroxylates a wide variety of alkylated DNA bases producing unstable intermediates which decompose to restore the non-alkylated bases. Homologues exist in other bacteria, metazoa (e.g. nine in humans), plants and viruses, but not in archaea, with many catalysing the same oxidative demethylation reactions as for AlkB. The mammalian enzymes Alkbh2 and Alkbh3 catalyse direct DNA repair, Alkbh5 and FTO (Alkbh9) are RNA demethylases, and Alkbh8 is used to synthesize a tRNA, while the remaining mammalian homologues have alternative functions. Alkbh1 is an apurinic/apyrimidinic lyase in addition to exhibiting demethylase activities, but no clear role for the Alkbh1 protein has emerged. Alkbh4 is involved in cell division and potentially demethylates actin, whereas the mitochondrial homologue Alkbh7 has a role in obesity; however, no enzymatic activity has been linked to Alkbh4 or Alkbh7. Here, we discuss AlkB as the ‘archetype’ of this class of hydroxylases, compare it to Alkbh2 and Alkbh3, and then briefly review the diverse (and largely unknown) functions of Alkbh1, Alkbh4, Alkbh6 and Alkbh7. Alkbh5, Alkbh8 and Alkbh9 (FTO) are described separately.
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Affiliation(s)
- Tina A. Müller
- Department of Microbiology and Molecular Genetics, Michigan State University East Lansing MI 48824 USA
| | - Robert P. Hausinger
- Department of Microbiology and Molecular Genetics, Michigan State University East Lansing MI 48824 USA
- Department of Biochemistry and Molecular Biology, Michigan State University East Lansing MI 48824 USA
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25
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Adhikari S, Chetram MA, Woodrick J, Mitra PS, Manthena PV, Khatkar P, Dakshanamurthy S, Dixon M, Karmahapatra SK, Nuthalapati NK, Gupta S, Narasimhan G, Mazumder R, Loffredo CA, Üren A, Roy R. Germ line variants of human N-methylpurine DNA glycosylase show impaired DNA repair activity and facilitate 1,N6-ethenoadenine-induced mutations. J Biol Chem 2014; 290:4966-4980. [PMID: 25538240 DOI: 10.1074/jbc.m114.627000] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Human N-methylpurine DNA glycosylase (hMPG) initiates base excision repair of a number of structurally diverse purine bases including 1,N(6)-ethenoadenine, hypoxanthine, and alkylation adducts in DNA. Genetic studies discovered at least eight validated non-synonymous single nucleotide polymorphisms (nsSNPs) of the hMPG gene in human populations that result in specific single amino acid substitutions. In this study, we tested the functional consequences of these nsSNPs of hMPG. Our results showed that two specific arginine residues, Arg-141 and Arg-120, are important for the activity of hMPG as the germ line variants R120C and R141Q had reduced enzymatic activity in vitro as well as in mammalian cells. Expression of these two variants in mammalian cells lacking endogenous MPG also showed an increase in mutations and sensitivity to an alkylating agent compared with the WT hMPG. Real time binding experiments by surface plasmon resonance spectroscopy suggested that these variants have substantial reduction in the equilibrium dissociation constant of binding (KD) of hMPG toward 1,N(6)-ethenoadenine-containing oligonucleotide (ϵA-DNA). Pre-steady-state kinetic studies showed that the substitutions at arginine residues affected the turnover of the enzyme significantly under multiple turnover condition. Surface plasmon resonance spectroscopy further showed that both variants had significantly decreased nonspecific (undamaged) DNA binding. Molecular modeling suggested that R141Q substitution may have resulted in a direct loss of the salt bridge between ϵA-DNA and hMPG, whereas R120C substitution redistributed, at a distance, the interactions among residues in the catalytic pocket. Together our results suggest that individuals carrying R120C and R141Q MPG variants may be at risk for genomic instability and associated diseases as a consequence.
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Affiliation(s)
- Sanjay Adhikari
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057,; Cancer Research Program, Houston Methodist Hospital Research Institute, Houston, Texas 77030, and
| | - Mahandranauth A Chetram
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Jordan Woodrick
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Partha S Mitra
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Praveen V Manthena
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Pooja Khatkar
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Sivanesan Dakshanamurthy
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Monica Dixon
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Soumendra K Karmahapatra
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Nikhil K Nuthalapati
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Suhani Gupta
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Ganga Narasimhan
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Raja Mazumder
- Department of Biochemistry and Molecular Medicine, The George Washington University, Washington, D. C. 20037
| | - Christopher A Loffredo
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Aykut Üren
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057
| | - Rabindra Roy
- From the Molecular Oncology Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D. C. 20057,.
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Goto M, Shinmura K, Matsushima Y, Ishino K, Yamada H, Totsuka Y, Matsuda T, Nakagama H, Sugimura H. Human DNA glycosylase enzyme TDG repairs thymine mispaired with exocyclic etheno-DNA adducts. Free Radic Biol Med 2014; 76:136-46. [PMID: 25151120 DOI: 10.1016/j.freeradbiomed.2014.07.044] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 07/14/2014] [Accepted: 07/31/2014] [Indexed: 11/24/2022]
Abstract
Lipid peroxidation directly reacts with DNA and produces various exocyclic etheno-base DNA adducts, some of which are considered to contribute to carcinogenesis. However, the system for repairing them in humans is largely unknown. We hypothesized that etheno-DNA adducts are repaired by base excision repair initiated by DNA glycosylase. To test this hypothesis, we examined the activities of the DNA glycosylase proteins OGG1, SMUG1, TDG, NEIL1, MUTYH, NTH1, MPG, and UNG2 against double-stranded oligonucleotides containing 1,N(6)-ethenoadenine (εA), 3,N(4)-ethenocytosine (εC), butanone-ethenocytosine (BεC), butanone-ethenoguanine (BεG), heptanone-ethenocytosine (HεC), or heptanone-ethenoguanine (HεG) using a DNA cleavage assay. We found that TDG is capable of removing thymine that has mispaired with εC, BεC, BεG, HεC, or HεG in vitro. We next examined the effect of TDG against etheno-DNA adducts in human cells. TDG-knockdown cells exhibited the following characteristics: (a) higher resistance to cell death caused by the induction of etheno-DNA adducts; (b) lower repair activity for εC; and (c) a modest acceleration of mutations caused by εC, compared with the rate in control cells. All these characteristics suggest that TDG exerts a repair activity against etheno-DNA adducts in human cells. These results suggest that TDG has novel repair activities toward etheno-DNA adducts.
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Affiliation(s)
- Masanori Goto
- Division of Cancer Development System, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan; Department of Tumor Pathology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi Ward, Hamamatsu, Shizuoka 431-3192, Japan
| | - Kazuya Shinmura
- Department of Tumor Pathology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi Ward, Hamamatsu, Shizuoka 431-3192, Japan.
| | - Yoshitaka Matsushima
- Department of Chemistry, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi Ward, Hamamatsu, Shizuoka 431-3192, Japan
| | - Kousuke Ishino
- Division of Cancer Development System, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan; Department of Pathology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8602, Japan
| | - Hidetaka Yamada
- Department of Tumor Pathology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi Ward, Hamamatsu, Shizuoka 431-3192, Japan
| | - Yukari Totsuka
- Division of Cancer Development System, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Tomonari Matsuda
- Research Center for Environmental Quality Management, Kyoto University, Otsu, Shiga, 520-0811, Japan
| | - Hitoshi Nakagama
- Division of Cancer Development System, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Haruhiko Sugimura
- Department of Tumor Pathology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi Ward, Hamamatsu, Shizuoka 431-3192, Japan.
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27
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Leitner-Dagan Y, Sevilya Z, Pinchev M, Kremer R, Elinger D, Rennert HS, Schechtman E, Freedman L, Rennert G, Livneh Z, Paz-Elizur T. Enzymatic MPG DNA repair assays for two different oxidative DNA lesions reveal associations with increased lung cancer risk. Carcinogenesis 2014; 35:2763-70. [PMID: 25355292 DOI: 10.1093/carcin/bgu214] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
DNA repair is a major mechanism for minimizing mutations and reducing cancer risk. Here, we present the development of reproducible and specific enzymatic assays for methylpurine DNA glycosylase (MPG) repairing the oxidative lesions 1,N6-ethenoadenine (εA) and hypoxanthine (Hx) in peripheral blood mononuclear cells protein extracts. Association of these DNA repair activities with lung cancer was determined using conditional logistic regression with specimens from a population-based case-control study with 96 lung cancer cases and 96 matched control subjects. The mean MPG-εA in case patients was 15.8 units/μg protein (95% CI 15.3-16.3), significantly higher than in control subjects-15.1 (14.6-15.5), *P = 0.011. The adjusted odds ratio for lung cancer associated with a one SD increase in MPG-εA activity (2.48 units) was significantly bigger than 1 (OR = 1.6, 95% CI = 1.1-2.4; *P = 0.013). When activity of OGG1, a different DNA repair enzyme for oxidative damage, was included in the model, the estimated odds ratio/SD for a combined MPG-εA-OGG1 score was 2.6 (95% CI 1.6-4.2) *P = 0.0001, higher than the odds ratio for each single assay. The MPG enzyme activity assays described provide robust functional risk biomarkers, with increased MPG-εA activity being associated with increased lung cancer risk, similar to the behavior of MPG-Hx. This underscores the notion that imbalances in DNA repair, including high DNA repair, usually perceived as beneficial, can cause cancer risk. Such DNA repair risk biomarkers may be useful for risk assessment of lung cancer and perhaps other cancer types, and for early detection techniques such as low-dose CT.
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Affiliation(s)
- Yael Leitner-Dagan
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel, Department of Community Medicine and Epidemiology, Carmel Medical Center, Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, and Clalit Health Services National Cancer Control Center, Haifa, Israel, Department of General Thoracic Surgery, Rambam Health Care Campus, Haifa, Israel, Department of Industrial Engineering and Management, Ben Gurion University of the Negev, Beer Sheva 84105, Israel and Biostatistics Unit, Gertner Institute for Epidemiology and Public Health Policy Sheba Medical Center Tel Hashomer 52621, Israel
| | - Ziv Sevilya
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel, Department of Community Medicine and Epidemiology, Carmel Medical Center, Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, and Clalit Health Services National Cancer Control Center, Haifa, Israel, Department of General Thoracic Surgery, Rambam Health Care Campus, Haifa, Israel, Department of Industrial Engineering and Management, Ben Gurion University of the Negev, Beer Sheva 84105, Israel and Biostatistics Unit, Gertner Institute for Epidemiology and Public Health Policy Sheba Medical Center Tel Hashomer 52621, Israel
| | - Mila Pinchev
- Department of Community Medicine and Epidemiology, Carmel Medical Center, Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, and Clalit Health Services National Cancer Control Center, Haifa, Israel
| | - Ran Kremer
- Department of General Thoracic Surgery, Rambam Health Care Campus, Haifa, Israel
| | - Dalia Elinger
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel, Department of Community Medicine and Epidemiology, Carmel Medical Center, Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, and Clalit Health Services National Cancer Control Center, Haifa, Israel, Department of General Thoracic Surgery, Rambam Health Care Campus, Haifa, Israel, Department of Industrial Engineering and Management, Ben Gurion University of the Negev, Beer Sheva 84105, Israel and Biostatistics Unit, Gertner Institute for Epidemiology and Public Health Policy Sheba Medical Center Tel Hashomer 52621, Israel
| | - Hedy S Rennert
- Department of Community Medicine and Epidemiology, Carmel Medical Center, Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, and Clalit Health Services National Cancer Control Center, Haifa, Israel
| | - Edna Schechtman
- Department of Industrial Engineering and Management, Ben Gurion University of the Negev, Beer Sheva 84105, Israel and
| | - Laurence Freedman
- Biostatistics Unit, Gertner Institute for Epidemiology and Public Health Policy Sheba Medical Center Tel Hashomer 52621, Israel
| | - Gad Rennert
- Department of Community Medicine and Epidemiology, Carmel Medical Center, Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, and Clalit Health Services National Cancer Control Center, Haifa, Israel
| | - Zvi Livneh
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel, Department of Community Medicine and Epidemiology, Carmel Medical Center, Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, and Clalit Health Services National Cancer Control Center, Haifa, Israel, Department of General Thoracic Surgery, Rambam Health Care Campus, Haifa, Israel, Department of Industrial Engineering and Management, Ben Gurion University of the Negev, Beer Sheva 84105, Israel and Biostatistics Unit, Gertner Institute for Epidemiology and Public Health Policy Sheba Medical Center Tel Hashomer 52621, Israel
| | - Tamar Paz-Elizur
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel, Department of Community Medicine and Epidemiology, Carmel Medical Center, Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, and Clalit Health Services National Cancer Control Center, Haifa, Israel, Department of General Thoracic Surgery, Rambam Health Care Campus, Haifa, Israel, Department of Industrial Engineering and Management, Ben Gurion University of the Negev, Beer Sheva 84105, Israel and Biostatistics Unit, Gertner Institute for Epidemiology and Public Health Policy Sheba Medical Center Tel Hashomer 52621, Israel
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28
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Aag-initiated base excision repair promotes ischemia reperfusion injury in liver, brain, and kidney. Proc Natl Acad Sci U S A 2014; 111:E4878-86. [PMID: 25349415 DOI: 10.1073/pnas.1413582111] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Inflammation is accompanied by the release of highly reactive oxygen and nitrogen species (RONS) that damage DNA, among other cellular molecules. Base excision repair (BER) is initiated by DNA glycosylases and is crucial in repairing RONS-induced DNA damage; the alkyladenine DNA glycosylase (Aag/Mpg) excises several DNA base lesions induced by the inflammation-associated RONS release that accompanies ischemia reperfusion (I/R). Using mouse I/R models we demonstrate that Aag(-/-) mice are significantly protected against, rather than sensitized to, I/R injury, and that such protection is observed across three different organs. Following I/R in liver, kidney, and brain, Aag(-/-) mice display decreased hepatocyte death, cerebral infarction, and renal injury relative to wild-type. We infer that in wild-type mice, Aag excises damaged DNA bases to generate potentially toxic abasic sites that in turn generate highly toxic DNA strand breaks that trigger poly(ADP-ribose) polymerase (Parp) hyperactivation, cellular bioenergetics failure, and necrosis; indeed, steady-state levels of abasic sites and nuclear PAR polymers were significantly more elevated in wild-type vs. Aag(-/-) liver after I/R. This increase in PAR polymers was accompanied by depletion of intracellular NAD and ATP levels plus the translocation and extracellular release of the high-mobility group box 1 (Hmgb1) nuclear protein, activating the sterile inflammatory response. We thus demonstrate the detrimental effects of Aag-initiated BER during I/R and sterile inflammation, and present a novel target for controlling I/R-induced injury.
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29
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Meira LB, Calvo JA, Shah D, Klapacz J, Moroski-Erkul CA, Bronson RT, Samson LD. Repair of endogenous DNA base lesions modulate lifespan in mice. DNA Repair (Amst) 2014; 21:78-86. [PMID: 24994062 PMCID: PMC4125484 DOI: 10.1016/j.dnarep.2014.05.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 04/30/2014] [Accepted: 05/20/2014] [Indexed: 12/21/2022]
Abstract
The accumulation of DNA damage is thought to contribute to the physiological decay associated with the aging process. Here, we report the results of a large-scale study examining longevity in various mouse models defective in the repair of DNA alkylation damage, or defective in the DNA damage response. We find that the repair of spontaneous DNA damage by alkyladenine DNA glycosylase (Aag/Mpg)-initiated base excision repair and O(6)-methylguanine DNA methyltransferase (Mgmt)-mediated direct reversal contributes to maximum life span in the laboratory mouse. We also uncovered important genetic interactions between Aag, which excises a wide variety of damaged DNA bases, and the DNA damage sensor and signaling protein, Atm. We show that Atm plays a role in mediating survival in the face of both spontaneous and induced DNA damage, and that Aag deficiency not only promotes overall survival, but also alters the tumor spectrum in Atm(-/-) mice. Further, the reversal of spontaneous alkylation damage by Mgmt interacts with the DNA mismatch repair pathway to modulate survival and tumor spectrum. Since these aging studies were performed without treatment with DNA damaging agents, our results indicate that the DNA damage that is generated endogenously accumulates with age, and that DNA alkylation repair proteins play a role in influencing longevity.
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Affiliation(s)
- Lisiane B Meira
- Biological Engineering Department, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States; Center for Environmental Health Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Jennifer A Calvo
- Biological Engineering Department, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States; Center for Environmental Health Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Dharini Shah
- Biological Engineering Department, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States; Center for Environmental Health Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Joanna Klapacz
- Biological Engineering Department, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States; Center for Environmental Health Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Catherine A Moroski-Erkul
- Biological Engineering Department, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States; Center for Environmental Health Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Roderick T Bronson
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States; Rodent Histopathology Core, Harvard Medical School, 126 Goldenson Building, Boston, MA 02115, United States
| | - Leona D Samson
- Biological Engineering Department, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States; Biology Department, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States; Center for Environmental Health Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States; Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States; Rodent Histopathology Core, Harvard Medical School, 126 Goldenson Building, Boston, MA 02115, United States.
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30
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Woodrick J, Gupta S, Khatkar P, Sarangi S, Narasimhan G, Trehan A, Adhikari S, Roy R. Slow repair of lipid peroxidation-induced DNA damage at p53 mutation hotspots in human cells caused by low turnover of a DNA glycosylase. Nucleic Acids Res 2014; 42:9033-46. [PMID: 25081213 PMCID: PMC4132702 DOI: 10.1093/nar/gku520] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 05/21/2014] [Accepted: 05/24/2014] [Indexed: 12/16/2022] Open
Abstract
Repair of oxidative stress- and inflammation-induced DNA lesions by the base excision repair (BER) pathway prevents mutation, a form of genomic instability which is often observed in cancer as 'mutation hotspots'. This suggests that some sequences have inherent mutability, possibly due to sequence-related differences in repair. This study has explored intrinsic mutability as a consequence of sequence-specific repair of lipid peroxidation-induced DNA adduct, 1, N(6)-ethenoadenine (εA). For the first time, we observed significant delay in repair of ϵA at mutation hotspots in the tumor suppressor gene p53 compared to non-hotspots in live human hepatocytes and endothelial cells using an in-cell real time PCR-based method. In-cell and in vitro mechanism studies revealed that this delay in repair was due to inefficient turnover of N-methylpurine-DNA glycosylase (MPG), which initiates BER of εA. We determined that the product dissociation rate of MPG at the hotspot codons was ≈5-12-fold lower than the non-hotspots, suggesting a previously unknown mechanism for slower repair at mutation hotspots and implicating sequence-related variability of DNA repair efficiency to be responsible for mutation hotspot signatures.
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Affiliation(s)
- Jordan Woodrick
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School, Washington, DC 20057, USA
| | - Suhani Gupta
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School, Washington, DC 20057, USA
| | - Pooja Khatkar
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School, Washington, DC 20057, USA
| | - Sanchita Sarangi
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School, Washington, DC 20057, USA
| | - Ganga Narasimhan
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School, Washington, DC 20057, USA
| | - Akriti Trehan
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School, Washington, DC 20057, USA
| | - Sanjay Adhikari
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School, Washington, DC 20057, USA
| | - Rabindra Roy
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School, Washington, DC 20057, USA
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31
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Zdżalik D, Vågbø CB, Kirpekar F, Davydova E, Puścian A, Maciejewska AM, Krokan HE, Klungland A, Tudek B, van den Born E, Falnes PØ. Protozoan ALKBH8 oxygenases display both DNA repair and tRNA modification activities. PLoS One 2014; 9:e98729. [PMID: 24914785 PMCID: PMC4051686 DOI: 10.1371/journal.pone.0098729] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 05/07/2014] [Indexed: 11/29/2022] Open
Abstract
The ALKBH family of Fe(II) and 2-oxoglutarate dependent oxygenases comprises enzymes that display sequence homology to AlkB from E. coli, a DNA repair enzyme that uses an oxidative mechanism to dealkylate methyl and etheno adducts on the nucleobases. Humans have nine different ALKBH proteins, ALKBH1–8 and FTO. Mammalian and plant ALKBH8 are tRNA hydroxylases targeting 5-methoxycarbonylmethyl-modified uridine (mcm5U) at the wobble position of tRNAGly(UCC). In contrast, the genomes of some bacteria encode a protein with strong sequence homology to ALKBH8, and robust DNA repair activity was previously demonstrated for one such protein. To further explore this apparent functional duality of the ALKBH8 proteins, we have here enzymatically characterized a panel of such proteins, originating from bacteria, protozoa and mimivirus. All the enzymes showed DNA repair activity in vitro, but, interestingly, two protozoan ALKBH8s also catalyzed wobble uridine modification of tRNA, thus displaying a dual in vitro activity. Also, we found the modification status of tRNAGly(UCC) to be unaltered in an ALKBH8 deficient mutant of Agrobacterium tumefaciens, indicating that bacterial ALKBH8s have a function different from that of their eukaryotic counterparts. The present study provides new insights on the function and evolution of the ALKBH8 family of proteins.
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Affiliation(s)
- Daria Zdżalik
- Department of Biosciences, University of Oslo, Oslo, Norway
- Institute of Genetics and Biotechnology, University of Warsaw, Warsaw, Poland
| | - Cathrine B. Vågbø
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Finn Kirpekar
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Erna Davydova
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Alicja Puścian
- Institute of Genetics and Biotechnology, University of Warsaw, Warsaw, Poland
- Department of Neurophysiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | | | - Hans E. Krokan
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Arne Klungland
- Clinic for Diagnostics and Intervention and Institute of Medical Microbiology, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Barbara Tudek
- Institute of Genetics and Biotechnology, University of Warsaw, Warsaw, Poland
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | | | - Pål Ø. Falnes
- Department of Biosciences, University of Oslo, Oslo, Norway
- * E-mail:
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32
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Lu L, Zhu C, Xia B, Yi C. Oxidative Demethylation of DNA and RNA Mediated by Non-Heme Iron-Dependent Dioxygenases. Chem Asian J 2014; 9:2018-29. [DOI: 10.1002/asia.201402148] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Indexed: 11/10/2022]
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33
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Nagel ZD, Chaim IA, Samson LD. Inter-individual variation in DNA repair capacity: a need for multi-pathway functional assays to promote translational DNA repair research. DNA Repair (Amst) 2014; 19:199-213. [PMID: 24780560 DOI: 10.1016/j.dnarep.2014.03.009] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Why does a constant barrage of DNA damage lead to disease in some individuals, while others remain healthy? This article surveys current work addressing the implications of inter-individual variation in DNA repair capacity for human health, and discusses the status of DNA repair assays as potential clinical tools for personalized prevention or treatment of disease. In particular, we highlight research showing that there are significant inter-individual variations in DNA repair capacity (DRC), and that measuring these differences provides important biological insight regarding disease susceptibility and cancer treatment efficacy. We emphasize work showing that it is important to measure repair capacity in multiple pathways, and that functional assays are required to fill a gap left by genome wide association studies, global gene expression and proteomics. Finally, we discuss research that will be needed to overcome barriers that currently limit the use of DNA repair assays in the clinic.
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Affiliation(s)
- Zachary D Nagel
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Isaac A Chaim
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Leona D Samson
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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34
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Affiliation(s)
- Guanqun Zheng
- Department of Chemistry and
Institute for Biophysical Dynamics, The
University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United
States
| | - Ye Fu
- Department of Chemistry and
Institute for Biophysical Dynamics, The
University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United
States
| | - Chuan He
- Department of Chemistry and
Institute for Biophysical Dynamics, The
University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United
States
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35
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Affiliation(s)
- Guanqun Zheng
- Department of Chemistry and Institute for Biophysical Dynamics, The University of Chicago , 929 East 57th Street, Chicago, Illinois 60637, United States
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Kidane D, Chae WJ, Czochor J, Eckert KA, Glazer PM, Bothwell ALM, Sweasy JB. Interplay between DNA repair and inflammation, and the link to cancer. Crit Rev Biochem Mol Biol 2014; 49:116-39. [PMID: 24410153 DOI: 10.3109/10409238.2013.875514] [Citation(s) in RCA: 117] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
DNA damage and repair are linked to cancer. DNA damage that is induced endogenously or from exogenous sources has the potential to result in mutations and genomic instability if not properly repaired, eventually leading to cancer. Inflammation is also linked to cancer. Reactive oxygen and nitrogen species (RONs) produced by inflammatory cells at sites of infection can induce DNA damage. RONs can also amplify inflammatory responses, leading to increased DNA damage. Here, we focus on the links between DNA damage, repair, and inflammation, as they relate to cancer. We examine the interplay between chronic inflammation, DNA damage and repair and review recent findings in this rapidly emerging field, including the links between DNA damage and the innate immune system, and the roles of inflammation in altering the microbiome, which subsequently leads to the induction of DNA damage in the colon. Mouse models of defective DNA repair and inflammatory control are extensively reviewed, including treatment of mouse models with pathogens, which leads to DNA damage. The roles of microRNAs in regulating inflammation and DNA repair are discussed. Importantly, DNA repair and inflammation are linked in many important ways, and in some cases balance each other to maintain homeostasis. The failure to repair DNA damage or to control inflammatory responses has the potential to lead to cancer.
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Affiliation(s)
- Dawit Kidane
- Departments of Therapeutic Radiology and Genetics
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Pang X, Han K, Cui Q. A simple but effective modeling strategy for structural properties of non-heme Fe(II) sites in proteins: test of force field models and application to proteins in the AlkB family. J Comput Chem 2013; 34:1620-35. [PMID: 23666816 DOI: 10.1002/jcc.23305] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 03/09/2013] [Accepted: 04/03/2013] [Indexed: 12/25/2022]
Abstract
To facilitate computational study of proteins in the AlkB family and related α-ketoglutarate/Fe(II)-dependent dioxygenases, we have tested a simple modeling strategy for the non-heme Fe(II) site in which the iron is represented by a simple +2 point charge with Lennard-Jones parameters. Calculations for an AlkB active site model in the gas phase and ∼150 ns molecular dynamics (MD) simulations for two enzyme-dsDNA complexes (E. coli AlkB-dsDNA and ABH2-dsDNA) suggest that this simple modeling strategy provides a satisfactory description of structural properties of the Fe(II) site in AlkB enzymes, provided that care is exercised to control the binding mode of carboxylate (Asp) to the iron. MD simulations using the model for AlkB-dsDNA and ABH2-dsDNA systems find that although the structural features for the latter are overall in good agreement with the crystal structure, the dsDNA, and AlkB-dsDNA interface undergo substantial changes during the MD simulations from the crystal structure. Even for ABH2, new interactions form between a long loop region and dsDNA upon structural relaxation of the loop, supporting the role of this loop in DNA binding despite the lack of interactions between them in the crystal structure. Analysis of DNA backbone torsional distributions helps identify regions that adopt strained conformations. Collectively, the results highlight that crystal packing may have a significant impact on the structure of protein-DNA complexes; the simulations also provide additional insights regarding why AlkB and ABH2 prefer single-strand and double-strand DNA, respectively, as substrate.
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Affiliation(s)
- Xueqin Pang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
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Alexeyev M, Shokolenko I, Wilson G, LeDoux S. The maintenance of mitochondrial DNA integrity--critical analysis and update. Cold Spring Harb Perspect Biol 2013; 5:a012641. [PMID: 23637283 DOI: 10.1101/cshperspect.a012641] [Citation(s) in RCA: 291] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
DNA molecules in mitochondria, just like those in the nucleus of eukaryotic cells, are constantly damaged by noxious agents. Eukaryotic cells have developed efficient mechanisms to deal with this assault. The process of DNA repair in mitochondria, initially believed nonexistent, has now evolved into a mature area of research. In recent years, it has become increasingly appreciated that mitochondria possess many of the same DNA repair pathways that the nucleus does. Moreover, a unique pathway that is enabled by high redundancy of the mitochondrial DNA and allows for the disposal of damaged DNA molecules operates in this organelle. In this review, we attempt to present a unified view of our current understanding of the process of DNA repair in mitochondria with an emphasis on issues that appear controversial.
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Affiliation(s)
- Mikhail Alexeyev
- Department of Cell Biology and Neuroscience, University of South Alabama, Mobile, AL 36688, USA
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Solberg A, Robertson AB, Aronsen JM, Rognmo Ø, Sjaastad I, Wisløff U, Klungland A. Deletion of mouse Alkbh7 leads to obesity. J Mol Cell Biol 2013; 5:194-203. [PMID: 23572141 DOI: 10.1093/jmcb/mjt012] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Mammals have nine homologues of the Escherichia coli AlkB repair protein: Alkbh1-8, and the fat mass and obesity associated protein FTO. In this report, we describe the first functional characterization of mouse Alkbh7. We show that the Alkbh7 protein is located in the mitochondrial matrix and that an Alkbh7 deletion dramatically increases body weight and body fat. Our data indicate that Alkbh7, directly or indirectly, facilitates the utilization of short-chain fatty acids, which we propose is the likely cause for the obesity phenotype observed in the Alkbh7(-/-) mice. Collectively, our data provide the first direct demonstration that murine Alkbh7 is a mitochondrial resident protein involved in fatty acid metabolism and the development of obesity.
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Affiliation(s)
- Anja Solberg
- Clinic for Diagnostics and Intervention and Institute of Medical Microbiology, Oslo University Hospital, Rikshospitalet, 0027 Oslo, Norway
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40
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Prestwich EG, Mangerich A, Pang B, McFaline JL, Lonkar P, Sullivan MR, Trudel LJ, Taghizedeh K, Dedon PC. Increased levels of inosine in a mouse model of inflammation. Chem Res Toxicol 2013; 26:538-46. [PMID: 23506120 DOI: 10.1021/tx300473n] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
One possible mechanism linking inflammation with cancer involves the generation of reactive oxygen, nitrogen, and halogen species by activated macrophages and neutrophils infiltrating sites of infection or tissue damage, with these chemical mediators causing damage that ultimately leads to cell death and mutation. To determine the most biologically deleterious chemistries of inflammation, we previously assessed products across the spectrum of DNA damage arising in inflamed tissues in the SJL mouse model nitric oxide overproduction ( Pang et al. ( 2007 ) Carcinogenesis 28 , 1807 - 1813 ). Among the anticipated DNA damage chemistries, we observed significant changes only in lipid peroxidation-derived etheno adducts. We have now developed an isotope-dilution, liquid chromatography-coupled, tandem quadrupole mass spectrometric method to quantify representative species across the spectrum of RNA damage products predicted to arise at sites of inflammation, including nucleobase deamination (xanthosine and inosine), oxidation (8-oxoguanosine), and alkylation (1,N(6)-ethenoadenosine). Application of the method to the liver, spleen, and kidney from the SJL mouse model revealed generally higher levels of oxidative background RNA damage than was observed in DNA in control mice. However, compared to control mice, RcsX treatment to induce nitric oxide overproduction resulted in significant increases only in inosine and only in the spleen. Further, the nitric oxide synthase inhibitor, N-methylarginine, did not significantly affect the levels of inosine in control and RcsX-treated mice. The differences between DNA and RNA damage in the same animal model of inflammation point to possible influences from DNA repair, RcsX-induced alterations in adenosine deaminase activity, and differential accessibility of DNA and RNA to reactive oxygen and nitrogen species as determinants of nucleic acid damage during inflammation.
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Affiliation(s)
- Erin G Prestwich
- Department of Biological Engineering and ‡Center for Environmental Health Science, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02193, United States
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Prorok P, Saint-Pierre C, Gasparutto D, Fedorova OS, Ishchenko AA, Leh H, Buckle M, Tudek B, Saparbaev M. Highly mutagenic exocyclic DNA adducts are substrates for the human nucleotide incision repair pathway. PLoS One 2012; 7:e51776. [PMID: 23251620 PMCID: PMC3522590 DOI: 10.1371/journal.pone.0051776] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Accepted: 11/12/2012] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Oxygen free radicals induce lipid peroxidation (LPO) that damages and breaks polyunsaturated fatty acids in cell membranes. LPO-derived aldehydes and hydroxyalkenals react with DNA leading to the formation of etheno(ε)-bases including 1,N(6)-ethenoadenine (εA) and 3,N(4)-ethenocytosine (εC). The εA and εC residues are highly mutagenic in mammalian cells and eliminated in the base excision repair (BER) pathway and/or by AlkB family proteins in the direct damage reversal process. BER initiated by DNA glycosylases is thought to be the major pathway for the removal of non-bulky endogenous base damage. Alternatively, in the nucleotide incision repair (NIR) pathway, the apurinic/apyrimidinic (AP) endonucleases can directly incise DNA duplex 5' to a damaged base in a DNA glycosylase-independent manner. METHODOLOGY/PRINCIPAL FINDINGS Here we have characterized the substrate specificity of human major AP endonuclease 1, APE1, towards εA, εC, thymine glycol (Tg) and 7,8-dihydro-8-oxoguanine (8oxoG) residues when present in duplex DNA. APE1 cleaves oligonucleotide duplexes containing εA, εC and Tg, but not those containing 8oxoG. Activity depends strongly on sequence context. The apparent kinetic parameters of the reactions suggest that APE1 has a high affinity for DNA containing ε-bases but cleaves DNA duplexes at an extremely slow rate. Consistent with this observation, oligonucleotide duplexes containing an ε-base strongly inhibit AP site nicking activity of APE1 with IC(50) values in the range of 5-10 nM. MALDI-TOF MS analysis of the reaction products demonstrated that APE1-catalyzed cleavage of εA•T and εC•G duplexes generates, as expected, DNA fragments containing 5'-terminal ε-base residue. CONCLUSIONS/SIGNIFICANCE The fact that ε-bases and Tg in duplex DNA are recognized and cleaved by APE1 in vitro, suggests that NIR may act as a backup pathway to BER to remove a large variety of genotoxic base lesions in human cells.
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Affiliation(s)
- Paulina Prorok
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
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42
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Maciejewska AM, Poznanski J, Kaczmarska Z, Krowisz B, Nieminuszczy J, Polkowska-Nowakowska A, Grzesiuk E, Kusmierek JT. AlkB dioxygenase preferentially repairs protonated substrates: specificity against exocyclic adducts and molecular mechanism of action. J Biol Chem 2012; 288:432-41. [PMID: 23148216 DOI: 10.1074/jbc.m112.353342] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Efficient repair by Escherichia coli AlkB dioxygenase of exocyclic DNA adducts 3,N(4)-ethenocytosine, 1,N(6)-ethenoadenine, 3,N(4)-α-hydroxyethanocytosine, and reported here for the first time 3,N(4)-α-hydroxypropanocytosine requires higher Fe(II) concentration than the reference 3-methylcytosine. The pH optimum for the repair follows the order of pK(a) values for protonation of the adduct, suggesting that positively charged substrates favorably interact with the negatively charged carboxylic group of Asp-135 side chain in the enzyme active center. This interaction is supported by molecular modeling, indicating that 1,N(6)-ethenoadenine and 3,N(4)-ethenocytosine are bound to AlkB more favorably in their protonated cationic forms. An analysis of the pattern of intermolecular interactions that stabilize the location of the ligand points to a role of Asp-135 in recognition of the adduct in its protonated form. Moreover, ab initio calculations also underline the role of substrate protonation in lowering the free energy barrier of the transition state of epoxidation of the etheno adducts studied. The observed time courses of repair of mixtures of stereoisomers of 3,N(4)-α-hydroxyethanocytosine or 3,N(4)-α-hydroxypropanocytosine are unequivocally two-exponential curves, indicating that the respective isomers are repaired by AlkB with different efficiencies. Molecular modeling of these adducts bound by AlkB allowed evaluation of the participation of their possible conformational states in the enzymatic reaction.
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Calvo JA, Meira LB, Lee CYI, Moroski-Erkul CA, Abolhassani N, Taghizadeh K, Eichinger LW, Muthupalani S, Nordstrand LM, Klungland A, Samson LD. DNA repair is indispensable for survival after acute inflammation. J Clin Invest 2012; 122:2680-9. [PMID: 22684101 DOI: 10.1172/jci63338] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 05/02/2012] [Indexed: 01/27/2023] Open
Abstract
More than 15% of cancer deaths worldwide are associated with underlying infections or inflammatory conditions, therefore understanding how inflammation contributes to cancer etiology is important for both cancer prevention and treatment. Inflamed tissues are known to harbor elevated etheno-base (ε-base) DNA lesions induced by the lipid peroxidation that is stimulated by reactive oxygen and nitrogen species (RONS) released from activated neutrophils and macrophages. Inflammation contributes to carcinogenesis in part via RONS-induced cytotoxic and mutagenic DNA lesions, including ε-base lesions. The mouse alkyl adenine DNA glycosylase (AAG, also known as MPG) recognizes such base lesions, thus protecting against inflammation-associated colon cancer. Two other DNA repair enzymes are known to repair ε-base lesions, namely ALKBH2 and ALKBH3; thus, we sought to determine whether these DNA dioxygenase enzymes could protect against chronic inflammation-mediated colon carcinogenesis. Using established chemically induced colitis and colon cancer models in mice, we show here that ALKBH2 and ALKBH3 provide cancer protection similar to that of the DNA glycosylase AAG. Moreover, Alkbh2 and Alkbh3 each display apparent epistasis with Aag. Surprisingly, deficiency in all 3 DNA repair enzymes confers a massively synergistic phenotype, such that animals lacking all 3 DNA repair enzymes cannot survive even a single bout of chemically induced colitis.
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Affiliation(s)
- Jennifer A Calvo
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
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Duplex interrogation by a direct DNA repair protein in search of base damage. Nat Struct Mol Biol 2012; 19:671-6. [PMID: 22659876 PMCID: PMC3392526 DOI: 10.1038/nsmb.2320] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 04/30/2012] [Indexed: 12/04/2022]
Abstract
ALKBH2 is a direct DNA repair dioxygenase guarding mammalian genome against N1-methyladenine, N3-methylcytosine, and 1,N6-ethenoadenine damage. A prerequisite for repair is to identify these lesions in the genome. Here we present crystal structures of ALKBH2 bound to different duplex DNAs. Together with computational and biochemical analyses, our results suggest that DNA interrogation by ALKBH2 displays two novel features: i) ALKBH2 probes base-pair stability and detects base pairs with reduced stability; ii) ALKBH2 does not have nor need a “damage-checking site”, which is critical for preventing spurious base-cleavage for several glycosylases. The demethylation mechanism of ALKBH2 insures that only cognate lesions are oxidized and reversed to normal bases, and that a flipped, non-substrate base remains intact in the active site. Overall, the combination of duplex interrogation and oxidation chemistry allows ALKBH2 to detect and process diverse lesions efficiently and correctly.
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45
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Tudek B, Speina E. Oxidatively damaged DNA and its repair in colon carcinogenesis. Mutat Res 2012; 736:82-92. [PMID: 22561673 DOI: 10.1016/j.mrfmmm.2012.04.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 04/02/2012] [Accepted: 04/16/2012] [Indexed: 12/18/2022]
Abstract
Inflammation, high fat, high red meat and low fiber consumption have for long been known as the most important etiological factors of sporadic colorectal cancers (CRC). Colon cancer originates from neoplastic transformation in a single layer of epithelial cells occupying colonic crypts, in which migration and apoptosis program becomes disrupted. This results in the formation of polyps and metastatic cancers. Mutational program in sporadic cancers involves APC gene, in which mutations occur most abundantly in the early phase of the process. This is followed by mutations in RAS, TP53, and other genes. Progression of carcinogenic process in the colon is accompanied by augmentation of the oxidative stress, which manifests in the increased level of oxidatively damaged DNA both in the colon epithelium, and in blood leukocytes and urine, already at the earliest stages of disease development. Defence mechanisms are deregulated in CRC patients: (i) antioxidative vitamins level in blood plasma declines with the development of disease; (ii) mRNA level of base excision repair enzymes in blood leukocytes of CRC patients is significantly increased; however, excision rate is regulated separately, being increased for 8-oxoGua, while decreased for lipid peroxidation derived ethenoadducts, ɛAde and ɛCyt; (iii) excision rate of ɛAde and ɛCyt in colon tumors is significantly increased in comparison to asymptomatic colon margin, and ethenoadducts level is decreased. This review highlights mechanisms underlying such deregulation, which is the driving force to colon carcinogenesis.
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Affiliation(s)
- Barbara Tudek
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
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46
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Meza TJ, Moen MN, Vågbø CB, Krokan HE, Klungland A, Grini PE, Falnes PØ. The DNA dioxygenase ALKBH2 protects Arabidopsis thaliana against methylation damage. Nucleic Acids Res 2012; 40:6620-31. [PMID: 22532610 PMCID: PMC3413135 DOI: 10.1093/nar/gks327] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The Escherichia coli AlkB protein (EcAlkB) is a DNA repair enzyme which reverses methylation damage such as 1-methyladenine (1-meA) and 3-methylcytosine (3-meC). The mammalian AlkB homologues ALKBH2 and ALKBH3 display EcAlkB-like repair activity in vitro, but their substrate specificities are different, and ALKBH2 is the main DNA repair enzyme for 1-meA in vivo. The genome of the model plant Arabidopsis thaliana encodes several AlkB homologues, including the yet uncharacterized protein AT2G22260, which displays sequence similarity to both ALKBH2 and ALKBH3. We have here characterized protein AT2G22260, by us denoted ALKBH2, as both our functional studies and bioinformatics analysis suggest it to be an orthologue of mammalian ALKBH2. The Arabidopsis ALKBH2 protein displayed in vitro repair activities towards methyl and etheno adducts in DNA, and was able to complement corresponding repair deficiencies of the E. coli alkB mutant. Interestingly, alkbh2 knock-out plants were sensitive to the methylating agent methylmethanesulphonate (MMS), and seedlings from these plants developed abnormally when grown in the presence of MMS. The present study establishes ALKBH2 as an important enzyme for protecting Arabidopsis against methylation damage in DNA, and suggests its homologues in other plants to have a similar function.
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Affiliation(s)
- Trine J Meza
- Department of Molecular Biosciences, University of Oslo, P.O. Box 1041 Blindern, N-0316 Oslo, Norway
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Korvald H, Falnes PØ, Laerdahl JK, Bjørås M, Alseth I. The Schizosaccharomyces pombe AlkB homolog Abh1 exhibits AP lyase activity but no demethylase activity. DNA Repair (Amst) 2012; 11:453-62. [PMID: 22365419 DOI: 10.1016/j.dnarep.2012.01.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 01/26/2012] [Accepted: 01/26/2012] [Indexed: 11/24/2022]
Abstract
2-Oxoglutarate (2OG) and iron (Fe(II)) dependent dioxygenases catalyze a wide range of biological oxidations, including hydroxylation and demethylation of proteins and nucleic acids. AlkB from Escherichia coli directly reverses certain methyl lesions in DNA, and defines a subfamily of 2OG/Fe(II) dioxygenases that has so far been shown to be involved in both nucleic acid repair and modification. The human genome encodes nine AlkB homologs and the function of most of these is still unknown. The fission yeast Schizosaccharomyces pombe has two AlkB homologs and here we have addressed the function of one of these, Abh1, which appears not to possess a classical AlkB-like repair activity. No enzymatic activity was found toward methylated DNA or etheno adducts, nor was the yeast abh1- mutant sensitive toward alkylating agents. Interestingly, heterologous expression of E. coli AlkB protected the fission yeast cells from alkylation induced cytotoxicity, suggesting that S. pombe lacks systems for efficient repair of lesions that are AlkB substrates. Further, we show that Abh1 possesses an unexpected DNA incision activity at apurinic/apyrimidinic (AP) sites. This AP lyase activity did not depend on 2OG and Fe(II) and was not repressed by dioxygenase inhibitors. Survival and complementation analyses failed to reveal any biological role for AP lyase cleavage by Abh1. It appears that in vitro AP lyase activity can be detected for a number of enzymes belonging to structurally and functionally unrelated families, but the in vivo significance of such activities may be questionable.
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Affiliation(s)
- Hanne Korvald
- Department of Microbiology, Oslo University Hospital HF Rikshospitalet, and Centre for Molecular Biology and Neuroscience (CMBN), University of Oslo, Oslo, Norway
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Winczura A, Zdżalik D, Tudek B. Damage of DNA and proteins by major lipid peroxidation products in genome stability. Free Radic Res 2012; 46:442-59. [PMID: 22257221 DOI: 10.3109/10715762.2012.658516] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Oxidative stress and lipid peroxidation (LPO) accompanying infections and chronic inflammation may induce several human cancers. LPO products are characterized by carbohydrate chains of different length, reactive aldehyde groups and double bonds, which make these molecules reactive to nucleic acids, proteins and cellular thiols. LPO-derived adducts to DNA bases form etheno-type and propano-type exocyclic rings, which have profound mutagenic potential, and are elevated in several cancer-prone diseases. Adducts of long chain LPO products to DNA bases inhibit transcription. Elimination from DNA of LPO-induced lesions is executed by several repair systems: base excision repair (BER), direct reversal by AlkB family proteins, nucleotide excision repair (NER) and recombination. Modifications of proteins with LPO products may regulate cellular processes like apoptosis, cell signalling and senescence. This review summarizes consequences of LPO products' presence in cell, particularly 4-hydroxy-2-nonenal, in terms of genomic stability.
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Affiliation(s)
- Alicja Winczura
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 02-106 Warsaw, Poland
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49
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DNA unwinding by ASCC3 helicase is coupled to ALKBH3-dependent DNA alkylation repair and cancer cell proliferation. Mol Cell 2011; 44:373-84. [PMID: 22055184 DOI: 10.1016/j.molcel.2011.08.039] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 06/08/2011] [Accepted: 08/27/2011] [Indexed: 12/26/2022]
Abstract
Demethylation by the AlkB dioxygenases represents an important mechanism for repair of N-alkylated nucleotides. However, little is known about their functions in mammalian cells. We report the purification of the ALKBH3 complex and demonstrate its association with the activating signal cointegrator complex (ASCC). ALKBH3 is overexpressed in various cancers, and both ALKBH3 and ASCC are important for alkylation damage resistance in these tumor cell lines. ASCC3, the largest subunit of ASCC, encodes a 3'-5' DNA helicase, whose activity is crucial for the generation of single-stranded DNA upon which ALKBH3 preferentially functions for dealkylation. In cell lines that are dependent on ALKBH3 and ASCC3 for alkylation damage resistance, loss of ALKBH3 or ASCC3 leads to increased 3-methylcytosine and reduced cell proliferation, which correlates with pH2A.X and 53BP1 foci formation. Our data provide a molecular mechanism by which ALKBH3 collaborates with ASCC to maintain genomic integrity in a cell-type specific manner.
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50
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Fu D, Samson LD. Direct repair of 3,N(4)-ethenocytosine by the human ALKBH2 dioxygenase is blocked by the AAG/MPG glycosylase. DNA Repair (Amst) 2011; 11:46-52. [PMID: 22079122 DOI: 10.1016/j.dnarep.2011.10.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Revised: 10/03/2011] [Accepted: 10/04/2011] [Indexed: 12/19/2022]
Abstract
Exocyclic ethenobases are highly mutagenic DNA lesions strongly implicated in inflammation and vinyl chloride-induced carcinogenesis. While the alkyladenine DNA glycosylase, AAG (or MPG), binds the etheno lesions 1,N(6)-ethenoadenine (ɛA) and 3,N(4)-ethenocytosine (ɛC) with high affinity, only ɛA can be excised to initiate base excision repair. Here, we discover that the human AlkB homolog 2 (ALKBH2) dioxygenase enzyme catalyzes direct reversal of ɛC lesions in both double- and single-stranded DNA with comparable efficiency to canonical ALKBH2 substrates. Notably, we find that in vitro, the non-enzymatic binding of AAG to ɛC specifically blocks ALKBH2-catalyzed repair of ɛC but not that of methylated ALKBH2 substrates. These results identify human ALKBH2 as a repair enzyme for mutagenic ɛC lesions and highlight potential consequences for substrate-binding overlap between the base excision and direct reversal DNA repair pathways.
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Affiliation(s)
- Dragony Fu
- Department of Biological Engineering, and Biology, Center for Environmental Health Sciences, David H. Koch Center for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
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