1
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Wang J, Takyi NA, Hsiao YC, Tang Q, Chen YT, Liu CW, Ma J, Qi R, Bian K, Peng Z, Essigmann JM, Lu K, Wetmore SD, Li D. Stable Interstrand Cross-Links Generated from the Repair of 1, N6-Ethenoadenine in DNA by α-Ketoglutarate/Fe(II)-Dependent Dioxygenase ALKBH2. J Am Chem Soc 2024; 146:10381-10392. [PMID: 38573229 PMCID: PMC11060877 DOI: 10.1021/jacs.3c12890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2024]
Abstract
DNA cross-links severely challenge replication and transcription in cells, promoting senescence and cell death. In this paper, we report a novel type of DNA interstrand cross-link (ICL) produced as a side product during the attempted repair of 1,N6-ethenoadenine (εA) by human α-ketoglutarate/Fe(II)-dependent enzyme ALKBH2. This stable/nonreversible ICL was characterized by denaturing polyacrylamide gel electrophoresis analysis and quantified by high-resolution LC-MS in well-matched and mismatched DNA duplexes, yielding 5.7% as the highest level for cross-link formation. The binary lesion is proposed to be generated through covalent bond formation between the epoxide intermediate of εA repair and the exocyclic N6-amino group of adenine or the N4-amino group of cytosine residues in the complementary strand under physiological conditions. The cross-links occur in diverse sequence contexts, and molecular dynamics simulations rationalize the context specificity of cross-link formation. In addition, the cross-link generated from attempted εA repair was detected in cells by highly sensitive LC-MS techniques, giving biological relevance to the cross-link adducts. Overall, a combination of biochemical, computational, and mass spectrometric methods was used to discover and characterize this new type of stable cross-link both in vitro and in human cells, thereby uniquely demonstrating the existence of a potentially harmful ICL during DNA repair by human ALKBH2.
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Affiliation(s)
- Jie Wang
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, Rhode Island 02881, United States
| | - Nathania A Takyi
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| | - Yun-Chung Hsiao
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Qi Tang
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, Rhode Island 02881, United States
| | - Yi-Tzai Chen
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, Rhode Island 02881, United States
| | - Chih-Wei Liu
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Jian Ma
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, Rhode Island 02881, United States
| | - Rui Qi
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, Rhode Island 02881, United States
| | - Ke Bian
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, Rhode Island 02881, United States
| | - Zhiyuan Peng
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, Rhode Island 02881, United States
| | - John M Essigmann
- Departments of Biological Engineering, Chemistry, and Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Kun Lu
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Stacey D Wetmore
- 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, Rhode Island 02881, United States
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2
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Crisalli AM, Chen YT, Cai A, Li D, Cho BP. Conformation-dependent lesion bypass of bulky arylamine-dG adducts generated from 2-nitrofluorene in epigenetic sequence contexts. Nucleic Acids Res 2023; 51:12043-12053. [PMID: 37953358 PMCID: PMC10711442 DOI: 10.1093/nar/gkad1038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 09/27/2023] [Accepted: 10/24/2023] [Indexed: 11/14/2023] Open
Abstract
Sequence context influences structural characteristics and repair of DNA adducts, but there is limited information on how epigenetic modulation affects conformational heterogeneity and bypass of DNA lesions. Lesions derived from the environmental pollutant 2-nitrofluorene have been extensively studied as chemical carcinogenesis models; they adopt a sequence-dependent mix of two significant conformers: major groove binding (B) and base-displaced stacked (S). We report a conformation-dependent bypass of the N-(2'-deoxyguanosin-8-yl)-7-fluoro-2-aminofluorene (dG-FAF) lesion in epigenetic sequence contexts (d[5'-CTTCTC#G*NCCTCATTC-3'], where C# is C or 5-methylcytosine (5mC), G* is G or G-FAF, and N is A, T, C or G). FAF-modified sequences with a 3' flanking pyrimidine were better bypassed when the 5' base was 5mC, whereas sequences with a 3' purine exhibited the opposite effect. The conformational basis behind these variations differed; for -CG*C- and -CG*T-, bypass appeared to be inversely correlated with population of the duplex-destabilizing S conformer. On the other hand, the connection between conformation and a decrease in bypass for flanking purines in the 5mC sequences relative to C was more complex. It could be related to the emergence of a disruptive non-S/B conformation. The present work provides novel conformational insight into how 5mC influences the bypass efficiency of bulky DNA damage.
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Affiliation(s)
- Alicia M Crisalli
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI 02881, USA
| | - Yi-Tzai Chen
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI 02881, USA
| | - Ang Cai
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI 02881, USA
| | - Deyu Li
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI 02881, USA
| | - Bongsup P Cho
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI 02881, USA
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3
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Li F, Wang Y, Zhang J. Kinetic isotope effect study of N-6 methyladenosine chemical demethylation in bicarbonate-activated peroxide system. J Chem Phys 2023; 159:124103. [PMID: 38127372 DOI: 10.1063/5.0169285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 09/05/2023] [Indexed: 12/23/2023] Open
Abstract
N-6 methyladenosine is the most abundant nucleic acid modification in eukaryotes and plays a crucial role in gene regulation. The AlkB family of alpha-ketoglutarate-dependent dioxygenases is responsible for nucleic acid demethylation. Recent studies have discovered that a chemical demethylation system using hydrogen peroxide and ammonium bicarbonate can effectively demethylate nucleic acids. The addition of ferrous ammonium sulfate boosts the oxidation rate by forming a Fenton reagent with hydrogen peroxide. However, the specific mechanism and key steps of this process remain unclear. In this study, we investigate the influence of ferrous ammonium sulfate concentration on the kinetic isotope effect (KIE) of the chemical demethylation system using LC-MS. As the concentration of ferrous ions increases, the observed KIE decreases from 1.377 ± 0.020 to 1.120 ± 0.016, indicating a combination of the primary isotope effect and inverse α-secondary isotope effect with the ion pairing effect. We propose that the initial hydrogen extraction is the rate-limiting step and observe a tight transition state structure in the formation of the hm6A process through the analysis of KIE trends. The concentration-dependent KIE provides a novel perspective on the mechanism of chemical demethylation and offers a chemical model for enzyme-catalyzed demethylation.
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Affiliation(s)
- Fangya Li
- School of Pharmaceutical Science and Technology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, People's Republic of China
| | - Ying Wang
- School of Pharmaceutical Science and Technology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, People's Republic of China
| | - Jianyu Zhang
- School of Pharmaceutical Science and Technology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, People's Republic of China
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4
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Zhang L, Ding X, Kratka CR, Levine A, Lee JK. Gas Phase Experimental and Computational Studies of AlkB Substrates: Intrinsic Properties and Biological Implications. J Org Chem 2023; 88:13115-13124. [PMID: 37651719 DOI: 10.1021/acs.joc.3c01335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
The gas phase acidity and proton affinity of nucleobases that are substrates for the DNA repair enzyme AlkB have been examined using both computational and experimental methods. These thermochemical values have not heretofore been measured and provide experimental data that help benchmark the theoretical results. We also use our gas phase results to lend insight into the AlkB mechanism, particularly in terms of the role AlkB plays in DNA repair, versus its complementary enzyme AlkA.
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Affiliation(s)
- Lanxin Zhang
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
| | - Xiao Ding
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
| | - Catherine R Kratka
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
| | - Alec Levine
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
| | - Jeehiun K Lee
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
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5
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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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6
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Peng Z, Ma J, Christov CZ, Karabencheva-Christova T, Lehnert N, Li D. Kinetic Studies on the 2-Oxoglutarate/Fe(II)-Dependent Nucleic Acid Modifying Enzymes from the AlkB and TET Families. DNA 2023; 3:65-84. [PMID: 38698914 PMCID: PMC11065319 DOI: 10.3390/dna3020005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
Nucleic acid methylations are important genetic and epigenetic biomarkers. The formation and removal of these markers is related to either methylation or demethylation. In this review, we focus on the demethylation or oxidative modification that is mediated by the 2-oxoglutarate (2-OG)/Fe(II)-dependent AlkB/TET family enzymes. In the catalytic process, most enzymes oxidize 2-OG to succinate, in the meantime oxidizing methyl to hydroxymethyl, leaving formaldehyde and generating demethylated base. The AlkB enzyme from Escherichia coli has nine human homologs (ALKBH1-8 and FTO) and the TET family includes three members, TET1 to 3. Among them, some enzymes have been carefully studied, but for certain enzymes, few studies have been carried out. This review focuses on the kinetic properties of those 2-OG/Fe(II)-dependent enzymes and their alkyl substrates. We also provide some discussions on the future directions of this field.
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Affiliation(s)
- Zhiyuan Peng
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI 02881, USA
| | - Jian Ma
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI 02881, USA
| | - Christo Z. Christov
- Department of Chemistry, Michigan Technological University, Houghton, MI 49931, USA
| | | | - Nicolai Lehnert
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Deyu Li
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI 02881, USA
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7
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Li J, Hu Z, Liu D, Wang P. Mass spectrometry-based assays for assessing replicative bypass and repair of DNA alkylation in cells. RSC Adv 2023; 13:15490-15497. [PMID: 37223415 PMCID: PMC10201546 DOI: 10.1039/d2ra08340j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 05/15/2023] [Indexed: 05/25/2023] Open
Abstract
Endogenous metabolism and environmental exposure can give rise to DNA alkylation, which can elicit deleterious biological consequences. In the search for reliable and quantitative analytical methods to elucidate the impact of DNA alkylation on the flow of genetic information, mass spectrometry (MS) has attracted increasing attention, owing to its unambiguous determination of molecular mass. The MS-based assays obviate conventional colony-picking methods and Sanger sequencing procedures, and retained the high sensitivity of postlabeling methods. With the help of the CRISPR/Cas9 gene editing method, MS-based assays showed high potential in studying individual functions of repair proteins and translesion synthesis (TLS) polymerases in DNA replication. In this mini-review, we have summarized the development of MS-based competitive and replicative adduct bypass (CRAB) assays and their recent applications in assessing the impact of alkylation on DNA replication. With further development of MS instruments for high resolving power and high throughput, these assays should be generally applicable and efficient in quantitative measurement of the biological consequences and repair of other DNA lesions.
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Affiliation(s)
- Jiaxian Li
- Institute of Surface Analysis and Chemical Biology, University of Jinan Jinan Shandong 250022 P. R. China
| | - Zhihai Hu
- Institute of Surface Analysis and Chemical Biology, University of Jinan Jinan Shandong 250022 P. R. China
| | - Dandan Liu
- Institute of Surface Analysis and Chemical Biology, University of Jinan Jinan Shandong 250022 P. R. China
| | - Pengcheng Wang
- Institute of Surface Analysis and Chemical Biology, University of Jinan Jinan Shandong 250022 P. R. China
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8
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Fahrer J, Christmann M. DNA Alkylation Damage by Nitrosamines and Relevant DNA Repair Pathways. Int J Mol Sci 2023; 24:ijms24054684. [PMID: 36902118 PMCID: PMC10003415 DOI: 10.3390/ijms24054684] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 02/17/2023] [Accepted: 02/24/2023] [Indexed: 03/04/2023] Open
Abstract
Nitrosamines occur widespread in food, drinking water, cosmetics, as well as tobacco smoke and can arise endogenously. More recently, nitrosamines have been detected as impurities in various drugs. This is of particular concern as nitrosamines are alkylating agents that are genotoxic and carcinogenic. We first summarize the current knowledge on the different sources and chemical nature of alkylating agents with a focus on relevant nitrosamines. Subsequently, we present the major DNA alkylation adducts induced by nitrosamines upon their metabolic activation by CYP450 monooxygenases. We then describe the DNA repair pathways engaged by the various DNA alkylation adducts, which include base excision repair, direct damage reversal by MGMT and ALKBH, as well as nucleotide excision repair. Their roles in the protection against the genotoxic and carcinogenic effects of nitrosamines are highlighted. Finally, we address DNA translesion synthesis as a DNA damage tolerance mechanism relevant to DNA alkylation adducts.
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Affiliation(s)
- Jörg Fahrer
- Division of Food Chemistry and Toxicology, Department of Chemistry, RPTU Kaiserslautern-Landau, Erwin-Schrödinger Strasse 52, D-67663 Kaiserslautern, Germany
- Correspondence: (J.F.); (M.C.); Tel.: +496312052974 (J.F.); Tel: +496131179066 (M.C.)
| | - Markus Christmann
- Department of Toxicology, University Medical Center Mainz, Obere Zahlbacher Strasse 67, D-55131 Mainz, Germany
- Correspondence: (J.F.); (M.C.); Tel.: +496312052974 (J.F.); Tel: +496131179066 (M.C.)
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9
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Ma X, Shi L, Xie H, Kuang D, Xu Y, Ma J, Yang J, Sun L. Sensitive Detection of Fat Mass and Obesity-Associated Protein based on Terminal Deoxynucleotidyl Transferase-Mediated Signal Amplification. Microchem J 2022. [DOI: 10.1016/j.microc.2022.108131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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10
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Aralov AV, Gubina N, Cabrero C, Tsvetkov VB, Turaev AV, Fedeles BI, Croy RG, Isaakova EA, Melnik D, Dukova S, Ryazantsev DY, Khrulev AA, Varizhuk AM, González C, Zatsepin TS, Essigmann JM. 7,8-Dihydro-8-oxo-1,N6-ethenoadenine: an exclusively Hoogsteen-paired thymine mimic in DNA that induces A→T transversions in Escherichia coli. Nucleic Acids Res 2022; 50:3056-3069. [PMID: 35234900 PMCID: PMC8989528 DOI: 10.1093/nar/gkac148] [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: 08/11/2021] [Revised: 02/09/2022] [Accepted: 02/25/2022] [Indexed: 12/15/2022] Open
Abstract
This work investigated the structural and biological properties of DNA containing 7,8-dihydro-8-oxo-1,N6-ethenoadenine (oxo-ϵA), a non-natural synthetic base that combines structural features of two naturally occurring DNA lesions (7,8-dihydro-8-oxoadenine and 1,N6-ethenoadenine). UV-, CD-, NMR spectroscopies and molecular modeling of DNA duplexes revealed that oxo-ϵA adopts the non-canonical syn conformation (χ = 65º) and fits very well among surrounding residues without inducing major distortions in local helical architecture. The adduct remarkably mimics the natural base thymine. When considered as an adenine-derived DNA lesion, oxo-ϵA was >99% mutagenic in living cells, causing predominantly A→T transversion mutations in Escherichia coli. The adduct in a single-stranded vector was not repaired by base excision repair enzymes (MutM and MutY glycosylases) or the AlkB dioxygenase and did not detectably affect the efficacy of DNA replication in vivo. When the biological and structural data are viewed together, it is likely that the nearly exclusive syn conformation and thymine mimicry of oxo-ϵA defines the selectivity of base pairing in vitro and in vivo, resulting in lesion pairing with A during replication. The base pairing properties of oxo-ϵA, its strong fluorescence and its invisibility to enzymatic repair systems in vivo are features that are sought in novel DNA-based probes and modulators of gene expression.
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Affiliation(s)
- Andrey V Aralov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow 117997, Russia
| | - Nina Gubina
- Department of Biological Engineering, Department of Chemistry and Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Institute of Theoretical and Experimental Biophysics RAS, Pushchino 142290, Russia
| | - Cristina Cabrero
- Instituto de Química-Física Rocasolano (IQFR-CSIC), Madrid 28006, Spain
| | - Vladimir B Tsvetkov
- Federal Research and Clinical Center of Physical Chemical Medicine of Federal Medical Biological Agency, Moscow 119435, Russia.,World-Class Research Center "Digital biodesign and personalized healthcare", Sechenov First Moscow State Medical University, Moscow 119146, Russia
| | - Anton V Turaev
- Federal Research and Clinical Center of Physical Chemical Medicine of Federal Medical Biological Agency, Moscow 119435, Russia
| | - Bogdan I Fedeles
- Department of Biological Engineering, Department of Chemistry and Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Robert G Croy
- Department of Biological Engineering, Department of Chemistry and Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ekaterina A Isaakova
- Federal Research and Clinical Center of Physical Chemical Medicine of Federal Medical Biological Agency, Moscow 119435, Russia
| | - Denis Melnik
- Center for Life Sciences, Skolkovo Institute of Science and Technology, Moscow 143026, Russia
| | - Svetlana Dukova
- Center for Life Sciences, Skolkovo Institute of Science and Technology, Moscow 143026, Russia
| | - Dmitriy Y Ryazantsev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow 117997, Russia
| | - Alexei A Khrulev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow 117997, Russia
| | - Anna M Varizhuk
- Federal Research and Clinical Center of Physical Chemical Medicine of Federal Medical Biological Agency, Moscow 119435, Russia.,Moscow Institute of Physics and Technology, Dolgoprudny 141701, Russia
| | - Carlos González
- Instituto de Química-Física Rocasolano (IQFR-CSIC), Madrid 28006, Spain
| | - Timofei S Zatsepin
- Center for Life Sciences, Skolkovo Institute of Science and Technology, Moscow 143026, Russia.,Chemistry Department, Lomonosov Moscow State University, Moscow 119992, Russia
| | - John M Essigmann
- Department of Biological Engineering, Department of Chemistry and Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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11
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Schmidl D, Jonasson NSW, Menke A, Schneider S, Daumann L. Spectroscopic and in vitro investigations of Fe2+/α-Ketoglutarate-dependent enzymes involved in nucleic acid repair and modification. Chembiochem 2022; 23:e202100605. [PMID: 35040547 PMCID: PMC9401043 DOI: 10.1002/cbic.202100605] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/14/2022] [Indexed: 11/08/2022]
Abstract
The activation of molecular oxygen for the highly selective functionalization and repair of DNA and RNA nucleobases is achieved by α-ketoglutarate (α-KG)/iron-dependent dioxygenases. Enzymes of special interest are the human homologs AlkBH of Escherichia coli EcAlkB and ten-eleven translocation (TET) enzymes. These enzymes are involved in demethylation or dealkylation of DNA and RNA, although additional physiological functions are continuously being revealed. Given their importance, studying enzyme-substrate interactions, turnover and kinetic parameters is pivotal for the understanding of the mode of action of these enzymes. Diverse analytical methods, including X-ray crystallography, UV/Vis absorption, electron paramagnetic resonance (EPR), circular dichroism (CD) and NMR spectroscopy have been employed to study the changes in the active site and the overall enzyme structure upon substrate, cofactor and inhibitor addition. Several methods are now available to assess activity of these enzymes. By discussing limitations and possibilities of these techniques for EcAlkB, AlkBH and TET we aim to give a comprehensive synopsis from a bioinorganic point of view, addressing researchers from different disciplines working in the highly interdisciplinary and rapidly evolving field of epigenetic processes and DNA/RNA repair and modification.
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Affiliation(s)
- David Schmidl
- Ludwig-Maximilians-Universität München: Ludwig-Maximilians-Universitat Munchen, Chemistry, GERMANY
| | - Niko S W Jonasson
- Ludwig-Maximilians-Universität München: Ludwig-Maximilians-Universitat Munchen, Chemistry, GERMANY
| | - Annika Menke
- Ludwig-Maximilians-Universität München: Ludwig-Maximilians-Universitat Munchen, Chemistry, GERMANY
| | - Sabine Schneider
- Ludwig-Maximilians-Universität München: Ludwig-Maximilians-Universitat Munchen, Chemistry, GERMANY
| | - Lena Daumann
- Ludwig-Maximilians-Universität München, Department of Chemistry, Butenandtstr. 5-13, 81377, München, GERMANY
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12
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Perry GS, Das M, Woon ECY. Inhibition of AlkB Nucleic Acid Demethylases: Promising New Epigenetic Targets. J Med Chem 2021; 64:16974-17003. [PMID: 34792334 DOI: 10.1021/acs.jmedchem.1c01694] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The AlkB family of nucleic acid demethylases is currently of intense chemical, biological, and medical interest because of its critical roles in several key cellular processes, including epigenetic gene regulation, RNA metabolism, and DNA repair. Emerging evidence suggests that dysregulation of AlkB demethylases may underlie the pathogenesis of several human diseases, particularly obesity, diabetes, and cancer. Hence there is strong interest in developing selective inhibitors for these enzymes to facilitate their mechanistic and functional studies and to validate their therapeutic potential. Herein we review the remarkable advances made over the past 20 years in AlkB demethylase inhibition research. We discuss the rational design of reported inhibitors, their mode-of-binding, selectivity, cellular activity, and therapeutic opportunities. We further discuss unexplored structural elements of the AlkB subfamilies and propose potential strategies to enable subfamily selectivity. It is hoped that this perspective will inspire novel inhibitor design and advance drug discovery research in this field.
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Affiliation(s)
- Gemma S Perry
- School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
| | - Mohua Das
- Lab of Precision Oncology and Cancer Evolution, Genome Institute of Singapore, 60 Biopolis Street, Singapore 138672, Singapore
| | - Esther C Y Woon
- School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
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13
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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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14
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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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15
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Qi R, Bian K, Chen F, Tang Q, Zhou X, Li D. Sequence Dependent Repair of 1, N6-Ethenoadenine by DNA Repair Enzymes ALKBH2, ALKBH3, and AlkB. Molecules 2021; 26:molecules26175285. [PMID: 34500720 PMCID: PMC8434105 DOI: 10.3390/molecules26175285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/17/2021] [Accepted: 08/25/2021] [Indexed: 11/16/2022] Open
Abstract
Mutation patterns of DNA adducts, such as mutational spectra and signatures, are useful tools for diagnostic and prognostic purposes. Mutational spectra of carcinogens derive from three sources: adduct formation, replication bypass, and repair. Here, we consider the repair aspect of 1,N6-ethenoadenine (εA) by the 2-oxoglutarate/Fe(II)-dependent AlkB family enzymes. Specifically, we investigated εA repair across 16 possible sequence contexts (5'/3' flanking base to εA varied as G/A/T/C). The results revealed that repair efficiency is altered according to sequence, enzyme, and strand context (ss- versus ds-DNA). The methods can be used to study other aspects of mutational spectra or other pathways of repair.
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16
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Guengerich FP, Ghodke PP. Etheno adducts: from tRNA modifications to DNA adducts and back to miscoding ribonucleotides. Genes Environ 2021; 43:24. [PMID: 34130743 PMCID: PMC8207595 DOI: 10.1186/s41021-021-00199-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 06/03/2021] [Indexed: 11/19/2022] Open
Abstract
Etheno (and ethano) derivatives of nucleic acid bases have an extra 5-membered ring attached. These were first noted as wyosine bases in tRNAs. Some were fluorescent, and the development of etheno derivatives of adenosine, cytosine, and guanosine led to the synthesis of fluorescent analogs of ATP, NAD+, and other cofactors for use in biochemical studies. Early studies with the carcinogen vinyl chloride revealed that these modified bases were being formed in DNA and RNA and might be responsible for mutations and cancer. The etheno bases are also derived from other carcinogenic vinyl monomers. Further work showed that endogenous etheno DNA adducts were present in animals and humans and are derived from lipid peroxidation. The chemical mechanisms of etheno adduct formation involve reactions with bis-electrophiles generated by cytochrome P450 enzymes or lipid peroxidation, which have been established in isotopic labeling studies. The mechanisms by which etheno DNA adducts miscode have been studied with several DNA polymerases, aided by the X-ray crystal structures of these polymerases in mispairing situations and in extension beyond mispairs. Repair of etheno DNA adduct damage is done primarily by glycosylases and also by the direct action of dioxygenases. Some human DNA polymerases (η, κ) can insert bases opposite etheno adducts in DNA and RNA, and the reverse transcriptase activity may be of relevance with the RNA etheno adducts. Further questions involve the extent that the etheno adducts contribute to human cancer.
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Affiliation(s)
- F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, 638B Robinson Research Building, 2200 Pierce Avenue, Nashville, TN, 37232-0146, USA.
| | - Pratibha P Ghodke
- Department of Biochemistry, Vanderbilt University School of Medicine, 638B Robinson Research Building, 2200 Pierce Avenue, Nashville, TN, 37232-0146, USA
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17
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Bayoumi M, Munir M. Structural Insights Into m6A-Erasers: A Step Toward Understanding Molecule Specificity and Potential Antiviral Targeting. Front Cell Dev Biol 2021; 8:587108. [PMID: 33511112 PMCID: PMC7835257 DOI: 10.3389/fcell.2020.587108] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 11/26/2020] [Indexed: 12/13/2022] Open
Abstract
The cellular RNA can acquire a variety of chemical modifications during the cell cycle, and compelling pieces of evidence highlight the importance of these modifications in determining the metabolism of RNA and, subsequently, cell physiology. Among myriads of modifications, methylation at the N6-position of adenosine (m6A) is the most important and abundant internal modification in the messenger RNA. The m6A marks are installed by methyltransferase complex proteins (writers) in the majority of eukaryotes and dynamically reversed by demethylases such as FTO and ALKBH5 (erasers). The incorporated m6A marks on the RNA transcripts are recognized by m6A-binding proteins collectively called readers. Recent epigenetic studies have unequivocally highlighted the association of m6A demethylases with a range of biomedical aspects, including human diseases, cancers, and metabolic disorders. Moreover, the mechanisms of demethylation by m6A erasers represent a new frontier in the future basic research on RNA biology. In this review, we focused on recent advances describing various physiological, pathological, and viral regulatory roles of m6A erasers. Additionally, we aim to analyze structural insights into well-known m6A-demethylases in assessing their substrate binding-specificity, efficiency, and selectivity. Knowledge on cellular and viral RNA metabolism will shed light on m6A-specific recognition by demethylases and will provide foundations for the future development of efficacious therapeutic agents to various cancerous conditions and open new avenues for the development of antivirals.
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Affiliation(s)
- Mahmoud Bayoumi
- Division of Biomedical and Life Sciences, Lancaster University, Lancaster, United Kingdom.,Virology Department, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| | - Muhammad Munir
- Division of Biomedical and Life Sciences, Lancaster University, Lancaster, United Kingdom
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18
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Abstract
Genomic DNA is chemically reactive and therefore susceptible to damage by many exogenous and endogenous sources. Lesions produced from these damaging events can have various mutagenic and genotoxic consequences. This Perspective follows the journey of one particular lesion, 1,N6-ethenoadenine (εA), from its formation to replication and repair, and its role in cancerous tissues and inflammatory diseases. εA is generated by the reaction of adenine (A) with vinyl chloride or lipid peroxidation products. We present the miscoding properties of εA with an emphasis on how bacterial and mammalian cells can process lesions differently, leading to varied mutational spectra. But with information from these assays, we can better understand how the miscoding properties of εA lead to biological consequences and how genomic stability can be maintained via DNA repair mechanisms. We discuss how base excision repair (BER) and direct reversal repair (DRR) can minimize the biological consequences of εA lesions. Kinetic parameters of glycosylases and AlkB family enzymes are described, along with a discussion of the relative contributions of the BER and DRR pathways in the repair of εA. Because eukaryotic DNA is packaged in chromatin, we also discuss the impact of this packaging on BER and DRR, specifically in regards to repair of εA. Studying DNA lesions like εA in this context, from origin to biological implications, can provide crucial information to better understand prevention of mutagenesis and cancer.
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Affiliation(s)
- Katelyn L Rioux
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Sarah Delaney
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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19
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Van Deuren V, Plessers S, Robben J. Structural determinants of nucleobase modification recognition in the AlkB family of dioxygenases. DNA Repair (Amst) 2020; 96:102995. [PMID: 33069898 DOI: 10.1016/j.dnarep.2020.102995] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 09/30/2020] [Indexed: 01/29/2023]
Abstract
Iron-dependent dioxygenases of the AlkB protein family found in most organisms throughout the tree of life play a major role in oxidative dealkylation processes. Many of these enzymes have attracted the attention of researchers across different fields and have been subjected to thorough biochemical characterization because of their link to human health and disease. For example, several mammalian AlkB homologues are involved in the direct reversal of alkylation damage in DNA, while others have been shown to play a regulatory role in epigenetic or epitranscriptomic nucleic acid methylation or in post-translational modifications such as acetylation of actin filaments. These studies show that that divergence in amino acid sequence and structure leads to different characteristics and substrate specificities. In this review, we aim to summarize current insights in the structural features involved in the substrate selection of AlkB homologues, with focus on nucleic acid interactions.
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Affiliation(s)
- V Van Deuren
- Department of Chemistry, KU Leuven, Celestijnenlaan 200G, B-3001, Heverlee, Belgium
| | - S Plessers
- Department of Chemistry, KU Leuven, Celestijnenlaan 200G, B-3001, Heverlee, Belgium
| | - J Robben
- Department of Chemistry, KU Leuven, Celestijnenlaan 200G, B-3001, Heverlee, Belgium.
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20
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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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21
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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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22
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Caffrey PJ, Kher R, Bian K, Li D, Delaney S. Comparison of the Base Excision and Direct Reversal Repair Pathways for Correcting 1, N6-Ethenoadenine in Strongly Positioned Nucleosome Core Particles. Chem Res Toxicol 2020; 33:1888-1896. [PMID: 32293880 PMCID: PMC7374743 DOI: 10.1021/acs.chemrestox.0c00089] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
![]()
1,N6-ethenoadenine (εA) is a
mutagenic lesion and biomarker observed in numerous cancerous tissues.
Two pathways are responsible for its repair: base excision repair
(BER) and direct reversal repair (DRR). Alkyladenine DNA glycosylase
(AAG) is the primary enzyme that excises εA in BER, generating
stable intermediates that are processed by downstream enzymes. For
DRR, the Fe(II)/α-ketoglutarate-dependent ALKBH2 enzyme repairs
εA by direct conversion of εA to A. While the molecular
mechanism of each enzyme is well understood on unpackaged duplex DNA,
less is known about their actions on packaged DNA. The nucleosome
core particle (NCP) forms the minimal packaging unit of DNA in eukaryotic
organisms and is composed of 145–147 base pairs wrapped around
a core of eight histone proteins. In this work, we investigated the
activity of AAG and ALKBH2 on εA lesions globally distributed
at positions throughout a strongly positioned NCP. Overall, we examined
the repair of εA at 23 unique locations in packaged DNA. We
observed a strong correlation between rotational positioning of εA
and AAG activity but not ALKBH2 activity. ALKBH2 was more effective
than AAG at repairing occluded εA lesions, but only AAG was
capable of full repair of any εA in the NCP. However, notable
exceptions to these trends were observed, highlighting the complexity
of the NCP as a substrate for DNA repair. Modeling of binding of the
repair enzymes to NCPs revealed that some of these observations can
be explained by steric interference caused by DNA packaging. Specifically,
interactions between ALKBH2 and the histone proteins obstruct binding
to DNA, which leads to diminished activity. Taken together, these
results support in vivo observations of alkylation
damage profiles and contribute to our understanding of mutational
hotspots.
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Affiliation(s)
- Paul J Caffrey
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Raadhika Kher
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Ke Bian
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, Rhode Island 02881, United States
| | - Deyu Li
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, Rhode Island 02881, United States
| | - Sarah Delaney
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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23
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Tudek A, Czerwińska J, Kosicki K, Zdżalik-Bielecka D, Shahmoradi Ghahe S, Bażlekowa-Karaban M, Borsuk EM, Speina E. DNA damage, repair and the improvement of cancer therapy - A tribute to the life and research of Barbara Tudek. Mutat Res 2020; 852:503160. [PMID: 32265045 DOI: 10.1016/j.mrgentox.2020.503160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 02/10/2020] [Accepted: 02/13/2020] [Indexed: 10/25/2022]
Abstract
Professor Barbara Tudek received the Frits Sobels Award in 2019 from the European Environmental Mutagenesis and Genomics Society (EEMGS). This article presents her outstanding character and most important lines of research. The focus of her studies covered alkylative and oxidative damage to DNA bases, in particular mutagenic and carcinogenic properties of purines with an open imidazole ring and 8-oxo-7,8-dihydroguanine (8-oxoGua). They also included analysis of mutagenic properties and pathways for the repair of DNA adducts of lipid peroxidation (LPO) products arising in large quantities during inflammation. Professor Tudek did all of this in the hope of deciphering the mechanisms of DNA damage removal, in particular by the base excision repair (BER) pathway. Some lines of research aimed at discovering factors that can modulate the activity of DNA damage repair in hope to enhance existing anti-cancer therapies. The group's ongoing research aims at deciphering the resistance mechanisms of cancer cell lines acquired following prolonged exposure to photodynamic therapy (PDT) and the possibility of re-sensitizing cells to PDT in order to increase the application of this minimally invasive therapeutic method.
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Affiliation(s)
- Agnieszka Tudek
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland
| | - Jolanta Czerwińska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland
| | - Konrad Kosicki
- Faculty of Biology, Institute of Genetics and Biotechnology, University of Warsaw, Pawińskiego 5a, 02-106 Warsaw, Poland
| | - Daria Zdżalik-Bielecka
- Laboratory of Cell Biology, International Institute of Molecular and Cell Biology, Księcia Trojdena 4, 02-109 Warsaw, Poland
| | - Somayeh Shahmoradi Ghahe
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland
| | - Milena Bażlekowa-Karaban
- Faculty of Biology, Institute of Genetics and Biotechnology, University of Warsaw, Pawińskiego 5a, 02-106 Warsaw, Poland; UMR 8200 C.N.R.S., Université Paris-Saclay, Gustave Roussy Cancer Campus, F-94805 Villejuif Cedex, France
| | - Ewelina M Borsuk
- Laboratory of Structural Biology, International Institute of Molecular and Cell Biology, Księcia Trojdena 4, 02-109 Warsaw, Poland
| | - Elżbieta Speina
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland.
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24
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Kanazhevskaya LY, Alekseeva IV, Fedorova OS. A Single-Turnover Kinetic Study of DNA Demethylation Catalyzed by Fe(II)/α-Ketoglutarate-Dependent Dioxygenase AlkB. Molecules 2019; 24:molecules24244576. [PMID: 31847292 PMCID: PMC6943663 DOI: 10.3390/molecules24244576] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 11/26/2019] [Accepted: 12/11/2019] [Indexed: 01/31/2023] Open
Abstract
AlkB is a Fe(II)/α-ketoglutarate-dependent dioxygenase that repairs some alkylated bases of DNA and RNA in Escherichia coli. In the course of catalysis, oxidation of a co-substrate (α-ketoglutarate, αKG) leads to the formation of a highly reactive ‘oxyferryl’ enzyme-bound intermediate, Fe(IV) = O, ensuring hydroxylation of the alkyl nucleobase adducts. Previous studies have revealed that AlkB is a flexible protein and can adopt different conformations during interactions with cofactors and DNA. To assess the conformational dynamics of the enzyme in complex with single- or double-stranded DNA in real-time mode, we employed the stopped-flow fluorescence method. N1-Methyladenine (m1A) introduced into a sequence of 15-mer oligonucleotides was chosen as the specific damage. Single-turnover kinetics were monitored by means of intrinsic fluorescence of the protein’s Trp residues, fluorescent base analogue 2-aminopurine (2aPu), and a dye–quencher pair (FAM/BHQ1). For all the fluorescent labels, the fluorescent traces showed several phases of consistent conformational changes, which were assigned to specific steps of the enzymatic process. These data offer an overall picture of the structural dynamics of AlkB and DNA during their interaction.
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Affiliation(s)
| | | | - Olga S. Fedorova
- Correspondence: (L.Y.K.); (O.S.F.); Tel.: +7-(383)-3635175 (O.S.F.)
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25
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Xie LJ, Liu L, Cheng L. Selective Inhibitors of AlkB Family of Nucleic Acid Demethylases. Biochemistry 2019; 59:230-239. [PMID: 31603665 DOI: 10.1021/acs.biochem.9b00774] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The α-ketoglutarate-dependent (AlkB) superfamily of FeII/2-oxoglutarate (2-OG)-dependent dioxygenases consists of a unique class of nucleic acid repair enzymes that reversibly remove alkyl substituents from nucleobases through oxidative dealkylation. Recent studies have verified the involvement of AlkB dioxygenases in a variety of human diseases. However, the development of small organic molecules that can function as enzyme inhibitors to block the action of oxidative dealkylation is still in its infancy. These purposeful chemical motifs, if capable of influencing the dealkylation activity, would have a potential clinical value by controlling genetic information expression. In this Perspective, we will summarize some of the most updated inhibitors of AlkB family demethylases and hope to provide a thought for the follow-up screening optimization.
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Affiliation(s)
- Li-Jun Xie
- Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.,University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Li Liu
- Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.,University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Liang Cheng
- Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.,University of Chinese Academy of Sciences , Beijing 100049 , China
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26
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Admiraal SJ, Eyler DE, Baldwin MR, Brines EM, Lohans CT, Schofield CJ, O'Brien PJ. Expansion of base excision repair compensates for a lack of DNA repair by oxidative dealkylation in budding yeast. J Biol Chem 2019; 294:13629-13637. [PMID: 31320474 PMCID: PMC6746446 DOI: 10.1074/jbc.ra119.009813] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 07/15/2019] [Indexed: 12/15/2022] Open
Abstract
The Mag1 and Tpa1 proteins from budding yeast (Saccharomyces cerevisiae) have both been reported to repair alkylation damage in DNA. Mag1 initiates the base excision repair pathway by removing alkylated bases from DNA, and Tpa1 has been proposed to directly repair alkylated bases as does the prototypical oxidative dealkylase AlkB from Escherichia coli. However, we found that in vivo repair of methyl methanesulfonate (MMS)-induced alkylation damage in DNA involves Mag1 but not Tpa1. We observed that yeast strains without tpa1 are no more sensitive to MMS than WT yeast, whereas mag1-deficient yeast are ∼500-fold more sensitive to MMS. We therefore investigated the substrate specificity of Mag1 and found that it excises alkylated bases that are known AlkB substrates. In contrast, purified recombinant Tpa1 did not repair these alkylated DNA substrates, but it did exhibit the prolyl hydroxylase activity that has also been ascribed to it. A comparison of several of the kinetic parameters of Mag1 and its E. coli homolog AlkA revealed that Mag1 catalyzes base excision from known AlkB substrates with greater efficiency than does AlkA, consistent with an expanded role of yeast Mag1 in repair of alkylation damage. Our results challenge the proposal that Tpa1 directly functions in DNA repair and suggest that Mag1-initiated base excision repair compensates for the absence of oxidative dealkylation of alkylated nucleobases in budding yeast. This expanded role of Mag1, as compared with alkylation repair glycosylases in other organisms, could explain the extreme sensitivity of Mag1-deficient S. cerevisiae toward alkylation damage.
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Affiliation(s)
- Suzanne J Admiraal
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
| | - Daniel E Eyler
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
| | - Michael R Baldwin
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
| | - Emily M Brines
- 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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Brickner JR, Townley BA, Mosammaparast N. Intersections between transcription-coupled repair and alkylation damage reversal. DNA Repair (Amst) 2019; 81:102663. [PMID: 31326362 DOI: 10.1016/j.dnarep.2019.102663] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The response to DNA damage intersects with many other physiological processes in the cell, such as DNA replication, chromatin remodeling, and the cell cycle. Certain damaging lesions, such as UV-induced pyrimidine dimers, also strongly block RNA polymerases, necessitating the coordination of the repair mechanism with remodeling of the elongating transcriptional machinery, in a process called transcription-coupled nucleotide excision repair (TC-NER). This pathway is typically not thought to be engaged with smaller lesions such as base alkylation. However, recent work has uncovered the potential for shared molecular components between the cellular response to alkylation and UV damage. Here, we review our current understanding of the alkylation damage response and its impacts on RNA biogenesis. We give particular attention to the Activating Signal Cointegrator Complex (ASCC), which plays important roles in the transcriptional response during UV damage as well as alkylation damage reversal, and intersects with trichothiodystrophy, an inherited disease associated with TC-NER.
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Affiliation(s)
- Joshua R Brickner
- Department of Pathology and Immunology, Division of Laboratory and Genomic Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Brittany A Townley
- Department of Pathology and Immunology, Division of Laboratory and Genomic Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Nima Mosammaparast
- Department of Pathology and Immunology, Division of Laboratory and Genomic Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA.
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Biological Evaluation of DNA Biomarkers in a Chemically Defined and Site-Specific Manner. TOXICS 2019; 7:toxics7020036. [PMID: 31242562 PMCID: PMC6631660 DOI: 10.3390/toxics7020036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 06/13/2019] [Accepted: 06/14/2019] [Indexed: 02/06/2023]
Abstract
As described elsewhere in this Special Issue on biomarkers, much progress has been made in the detection of modified DNA within organisms at endogenous and exogenous levels of exposure to chemical species, including putative carcinogens and chemotherapeutic agents. Advances in the detection of damaged or unnatural bases have been able to provide correlations to support or refute hypotheses between the level of exposure to oxidative, alkylative, and other stresses, and the resulting DNA damage (lesion formation). However, such stresses can form a plethora of modified nucleobases, and it is therefore difficult to determine the individual contribution of a particular modification to alter a cell's genetic fate, as measured in the form of toxicity by stalled replication past the damage, by subsequent mutation, and by lesion repair. Chemical incorporation of a modification at a specific site within a vector (site-specific mutagenesis) has been a useful tool to deconvolute what types of damage quantified in biologically relevant systems may lead to toxicity and/or mutagenicity, thereby allowing researchers to focus on the most relevant biomarkers that may impact human health. Here, we will review a sampling of the DNA modifications that have been studied by shuttle vector techniques.
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Muenter MM, Aiken A, Akanji JO, Baig S, Bellou S, Carlson A, Conway C, Cowell CM, DeLateur NA, Hester A, Joshi C, Kramer C, Leifer BS, Nash E, Qi MH, Travers M, Wong KC, Hu M, Gou N, Giese RW, Gu AZ, Beuning PJ. The response of Escherichia coli to the alkylating agents chloroacetaldehyde and styrene oxide. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2019; 840:1-10. [PMID: 30857727 DOI: 10.1016/j.mrgentox.2019.02.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Revised: 02/06/2019] [Accepted: 02/06/2019] [Indexed: 10/27/2022]
Abstract
DNA damage is ubiquitous and can arise from endogenous or exogenous sources. DNA-damaging alkylating agents are present in environmental toxicants as well as in cancer chemotherapy drugs and are a constant threat, which can lead to mutations or cell death. All organisms have multiple DNA repair and DNA damage tolerance pathways to resist the potentially negative effects of exposure to alkylating agents. In bacteria, many of the genes in these pathways are regulated as part of the SOS reponse or the adaptive response. In this work, we probed the cellular responses to the alkylating agents chloroacetaldehyde (CAA), which is a metabolite of 1,2-dichloroethane used to produce polyvinyl chloride, and styrene oxide (SO), a major metabolite of styrene used in the production of polystyrene and other polymers. Vinyl chloride and styrene are produced on an industrial scale of billions of kilograms annually and thus have a high potential for environmental exposure. To identify stress response genes in E. coli that are responsible for tolerance to the reactive metabolites CAA and SO, we used libraries of transcriptional reporters and gene deletion strains. In response to both alkylating agents, genes associated with several different stress pathways were upregulated, including protein, membrane, and oxidative stress, as well as DNA damage. E. coli strains lacking genes involved in base excision repair and nucleotide excision repair were sensitive to SO, whereas strains lacking recA and the SOS gene ybfE were sensitive to both alkylating agents tested. This work indicates the varied systems involved in cellular responses to alkylating agents, and highlights the specific DNA repair genes involved in the responses.
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Affiliation(s)
- Mark M Muenter
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Ariel Aiken
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Jadesola O Akanji
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Samir Baig
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Sirine Bellou
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Alyssa Carlson
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Charles Conway
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Courtney M Cowell
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Nicholas A DeLateur
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Alexis Hester
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Christopher Joshi
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Caitlin Kramer
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Becky S Leifer
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Emma Nash
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Macee H Qi
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Meghan Travers
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Kelly C Wong
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA
| | - Man Hu
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, 02115 USA
| | - Na Gou
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, 02115 USA; School of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14850, USA
| | - Roger W Giese
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, 02115 USA
| | - April Z Gu
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, 02115 USA; School of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14850, USA
| | - Penny J Beuning
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, 02115 USA.
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Mohan M, Pandya V, Anindya R. Escherichia coli AlkB and single-stranded DNA binding protein SSB interaction explored by Molecular Dynamics Simulation. J Mol Graph Model 2018; 84:29-35. [DOI: 10.1016/j.jmgm.2018.05.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/30/2018] [Accepted: 05/16/2018] [Indexed: 12/15/2022]
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Nigam R, Anindya R. Escherichia coli single-stranded DNA binding protein SSB promotes AlkB-mediated DNA dealkylation repair. Biochem Biophys Res Commun 2018; 496:274-279. [PMID: 29326044 DOI: 10.1016/j.bbrc.2018.01.043] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 01/06/2018] [Indexed: 11/17/2022]
Abstract
Repair of alkylation damage in DNA is essential for maintaining genome integrity. Escherichia coli (E.coli) protein AlkB removes various alkyl DNA adducts including N1-methyladenine (N1meA) and N3-methylcytosine (N3meC) by oxidative demethylation. Previous studies showed that AlkB preferentially removes N1meA and N3meC from single-stranded DNA (ssDNA). It can also remove N1meA and N3meC from double-stranded DNA by base-flipping. Notably, ssDNA produced during DNA replication and recombination, remains bound to E. coli single-stranded DNA binding protein SSB and it is not known whether AlkB can repair methyl adduct present in SSB-coated DNA. Here we have studied AlkB-mediated DNA repair using SSB-bound DNA as substrate. In vitro repair reaction revealed that AlkB could efficiently remove N3meC adducts inasmuch as DNA length is shorter than 20 nucleotides. However, when longer N3meC-containing oligonuleotides were used as the substrate, efficiency of AlkB catalyzed reaction was abated compared to SSB-bound DNA substrate of identical length. Truncated SSB containing only the DNA binding domain could also support the stimulation of AlkB activity, suggesting the importance of SSB-DNA interaction for AlkB function. Using 70-mer oligonucleotide containing single N3meC we demonstrate that SSB-AlkB interaction promotes faster repair of the methyl DNA adducts.
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Affiliation(s)
- Richa Nigam
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Hyderabad 502285, Telangana, India
| | - Roy Anindya
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Hyderabad 502285, Telangana, India.
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32
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Tang Q, Cai A, Bian K, Chen F, Delaney JC, Adusumalli S, Bach AC, Akhlaghi F, Cho BP, Li D. Characterization of Byproducts from Chemical Syntheses of Oligonucleotides Containing 1-Methyladenine and 3-Methylcytosine. ACS OMEGA 2017; 2:8205-8212. [PMID: 29214236 PMCID: PMC5709782 DOI: 10.1021/acsomega.7b01482] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 11/01/2017] [Indexed: 06/07/2023]
Abstract
Oligonucleotides serve as important tools for biological, chemical, and medical research. The preparation of oligonucleotides through automated solid-phase synthesis is well-established. However, identification of byproducts generated from DNA synthesis, especially from oligonucleotides containing site-specific modifications, is sometimes challenging. Typical high-performance liquid chromatography (HPLC), mass spectrometry (MS), and gel electrophoresis methods alone are not sufficient for characterizing unexpected byproducts, especially for those having identical or very similar molecular weight (MW) to the products. We used a rigorous quality control procedure to characterize byproducts generated during oligonucleotide syntheses: (1) purify oligonucleotides by different HPLC systems; (2) determine exact MW by high-resolution MS; (3) locate modification position by MS/MS or exonuclease digestion with matrix-assisted laser desorption ionization-time of flight analysis; and (4) conduct, where applicable, enzymatic assays. We applied these steps to characterize byproducts in the syntheses of oligonucleotides containing biologically important methyl DNA adducts 1-methyladenine (m1A) and 3-methylcytosine (m3C). In m1A synthesis, we differentiated a regioisomeric byproduct 6-methyladenine, which possesses a MW identical to uncharged m1A. As for m3C, we identified a deamination byproduct 3-methyluracil, which is only 1 Da greater than uncharged m3C in the ∼4900 Da context. The detection of these byproducts would be very challenging if the abovementioned procedure was not adopted.
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Affiliation(s)
- Qi Tang
- Department
of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, 7 Greenhouse Road, Kingston, Rhode Island 02881, United States
| | - Ang Cai
- Department
of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, 7 Greenhouse Road, Kingston, Rhode Island 02881, United States
| | - Ke Bian
- Department
of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, 7 Greenhouse Road, Kingston, Rhode Island 02881, United States
| | - Fangyi Chen
- Department
of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, 7 Greenhouse Road, Kingston, Rhode Island 02881, United States
| | - James C. Delaney
- Visterra
Inc., One Kendall Square, Cambridge, Massachusetts 02139, United States
| | - Sravani Adusumalli
- Department
of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, 7 Greenhouse Road, Kingston, Rhode Island 02881, United States
| | - Alvin C. Bach
- Department
of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, 7 Greenhouse Road, Kingston, Rhode Island 02881, United States
| | - Fatemeh Akhlaghi
- Department
of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, 7 Greenhouse Road, Kingston, Rhode Island 02881, United States
| | - Bongsup P. Cho
- Department
of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, 7 Greenhouse Road, Kingston, Rhode Island 02881, United States
| | - Deyu Li
- Department
of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, 7 Greenhouse Road, Kingston, Rhode Island 02881, United States
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Bian K, Chen F, Humulock ZT, Tang Q, Li D. Copper Inhibits the AlkB Family DNA Repair Enzymes under Wilson's Disease Condition. Chem Res Toxicol 2017; 30:1794-1796. [PMID: 28926697 DOI: 10.1021/acs.chemrestox.7b00230] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Disturbed metabolism of copper ions can cause diseases such as Wilson's disease (WD). In this work, we investigated the inhibitory effect of Cu(II) ion in vitro on the AlkB family DNA repair enzymes, which are members of the Fe(II)/alpha-ketoglutarate-dependent dioxygenase and include human ALKBH2, ALKBH3, and E. coli AlkB proteins. None of the three proteins was significantly inhibited under normal cellular copper concentrations. However, under WD related condition, we observed that the activities of all three enzymes were strongly suppressed (from 95.2 to 100.0%). We also noted the repair efficiency under ds-DNA condition was less susceptible than ss-DNA to the inhibition.
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Affiliation(s)
- Ke Bian
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Fangyi Chen
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Zachary T Humulock
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Qi Tang
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Deyu Li
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
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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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1,N 6-α-hydroxypropanoadenine, the acrolein adduct to adenine, is a substrate for AlkB dioxygenase. Biochem J 2017; 474:1837-1852. [PMID: 28408432 DOI: 10.1042/bcj20161008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 04/07/2017] [Accepted: 04/13/2017] [Indexed: 11/17/2022]
Abstract
1,N6-α-hydroxypropanoadenine (HPA) is an exocyclic DNA adduct of acrolein - an environmental pollutant and endocellular oxidative stress product. Escherichia coli AlkB dioxygenase belongs to the superfamily of α-ketoglutarate (αKG)- and iron-dependent dioxygenases which remove alkyl lesions from bases via an oxidative mechanism, thereby restoring native DNA structure. Here, we provide in vivo and in vitro evidence that HPA is mutagenic and is effectively repaired by AlkB dioxygenase. HPA generated in plasmid DNA caused A → C and A → T transversions and, less frequently, A → G transitions. The lesion was efficiently repaired by purified AlkB protein; the optimal pH, Fe(II), and αKG concentrations for this reaction were determined. In vitro kinetic data show that the protonated form of HPA is preferentially repaired by AlkB, albeit the reaction is stereoselective. Moreover, the number of reaction cycles carried out by an AlkB molecule remains limited. Molecular modeling of the T(HPA)T/AlkB complex demonstrated that the R stereoisomer in the equatorial conformation of the HPA hydroxyl group is strongly preferred, while the S stereoisomer seems to be susceptible to AlkB-directed oxidative hydroxylation only when HPA adopts the syn conformation around the glycosidic bond. In addition to the biochemical activity assays, substrate binding to the protein was monitored by differential scanning fluorimetry allowing identification of the active protein form, with cofactor and cosubstrate bound, and monitoring of substrate binding. In contrast FTO, a human AlkB homolog, failed to bind an ssDNA trimer carrying HPA.
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Chang SC, Seneviratne UI, Wu J, Tretyakova N, Essigmann JM. 1,3-Butadiene-Induced Adenine DNA Adducts Are Genotoxic but Only Weakly Mutagenic When Replicated in Escherichia coli of Various Repair and Replication Backgrounds. Chem Res Toxicol 2017; 30:1230-1239. [PMID: 28394575 PMCID: PMC5512570 DOI: 10.1021/acs.chemrestox.7b00064] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The adverse effects of the human carcinogen 1,3-butadiene (BD) are believed to be mediated by its DNA-reactive metabolites such as 3,4-epoxybut-1-ene (EB) and 1,2,3,4-diepoxybutane (DEB). The specific DNA adducts responsible for toxic and mutagenic effects of BD, however, have yet to be identified. Recent in vitro polymerase bypass studies of BD-induced adenine (BD-dA) adducts show that DEB-induced N6,N6-DHB-dA (DHB = 2,3-dihydroxybutan-1,4-diyl) and 1,N6-γ-HMHP-dA (HMHP = 2-hydroxy-3-hydroxymethylpropan-1,3-diyl) adducts block replicative DNA polymerases but are bypassed by human polymerases η and κ, leading to point mutations and deletions. In contrast, EB-induced N6-HB-dA (HB = 2-hydroxy-3-buten-1-yl) does not block DNA synthesis and is nonmutagenic. In the present study, we employed a newly established in vivo lesion-induced mutagenesis/genotoxicity assay via next-generation sequencing to evaluate the in vivo biological consequences of S-N6-HB-dA, R,R-N6,N6-DHB-dA, S,S-N6,N6-DHB-dA, and R,S-1,N6-γ-HMHP-dA. In addition, the effects of AlkB-mediated direct reversal repair, MutM and MutY catalyzed base excision repair, and DinB translesion synthesis on the BD-dA adducts in bacterial cells were investigated. BD-dA adducts showed the expected inhibition of DNA replication in vivo but were not substantively mutagenic in any of the genetic environments investigated. This result is in contrast with previous in vitro observations and opens the possibility that E. coli repair and bypass systems other than the ones studied here are able to minimize the mutagenic properties of BD-dA adducts.
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Affiliation(s)
- Shiou-chi Chang
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
- Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Uthpala I. Seneviratne
- Department of Medicinal Chemistry, and the Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455
| | - Jie Wu
- BioMicro Center, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Natalia Tretyakova
- Department of Medicinal Chemistry, and the Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455
| | - John M. Essigmann
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
- Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139
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37
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Chen F, Bian K, Tang Q, Fedeles BI, Singh V, Humulock ZT, Essigmann JM, Li D. Oncometabolites d- and l-2-Hydroxyglutarate Inhibit the AlkB Family DNA Repair Enzymes under Physiological Conditions. Chem Res Toxicol 2017; 30:1102-1110. [PMID: 28269980 DOI: 10.1021/acs.chemrestox.7b00009] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Cancer-associated mutations often lead to perturbed cellular energy metabolism and accumulation of potentially harmful oncometabolites. One example is the chiral molecule 2-hydroxyglutarate (2HG); its two stereoisomers (d- and l-2HG) have been found at abnormally high concentrations in tumors featuring anomalous metabolic pathways. 2HG has been demonstrated to competitively inhibit several α-ketoglutarate (αKG)- and non-heme iron-dependent dioxygenases, including some of the AlkB family DNA repair enzymes, such as ALKBH2 and ALKBH3. However, previous studies have only provided the IC50 values of d-2HG on the enzymes, and the results have not been correlated to physiologically relevant concentrations of 2HG and αKG in cancer cells. In this work, we performed detailed kinetic analyses of DNA repair reactions catalyzed by ALKBH2, ALKBH3, and the bacterial AlkB in the presence of d- and l-2HG in both double- and single-stranded DNA contexts. We determined the kinetic parameters of inhibition, including kcat, KM, and Ki. We also correlated the relative concentrations of 2HG and αKG previously measured in tumor cells with the inhibitory effect of 2HG on the AlkB family enzymes. Both d- and l-2HG significantly inhibited the human DNA repair enzymes ALKBH2 and ALKBH3 at pathologically relevant concentrations (73-88% for d-2HG and 31-58% for l-2HG inhibition). This work provides a new perspective that the elevation of the d- or l-2HG concentration in cancer cells may contribute to an increased mutation rate by inhibiting the DNA repair performed by the AlkB family enzymes and thus exacerbate the genesis and progression of tumors.
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Affiliation(s)
- Fangyi Chen
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Ke Bian
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Qi Tang
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Bogdan I Fedeles
- Department of Biological Engineering, Department of Chemistry, and Center for Environmental Health Sciences, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Vipender Singh
- Department of Biological Engineering, Department of Chemistry, and Center for Environmental Health Sciences, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Zachary T Humulock
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - John M Essigmann
- Department of Biological Engineering, Department of Chemistry, and Center for Environmental Health Sciences, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Deyu Li
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
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38
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Regulation of DNA Alkylation Damage Repair: Lessons and Therapeutic Opportunities. Trends Biochem Sci 2016; 42:206-218. [PMID: 27816326 DOI: 10.1016/j.tibs.2016.10.001] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 10/03/2016] [Accepted: 10/11/2016] [Indexed: 12/15/2022]
Abstract
Alkylation chemotherapy is one of the most widely used systemic therapies for cancer. While somewhat effective, clinical responses and toxicities of these agents are highly variable. A major contributing factor for this variability is the numerous distinct lesions that are created upon alkylation damage. These adducts activate multiple repair pathways. There is mounting evidence that the individual pathways function cooperatively, suggesting that coordinated regulation of alkylation repair is critical to prevent toxicity. Furthermore, some alkylating agents produce adducts that overlap with newly discovered methylation marks, making it difficult to distinguish between bona fide damaged bases and so-called 'epigenetic' adducts. Here, we discuss new efforts aimed at deciphering the mechanisms that regulate these repair pathways, emphasizing their implications for cancer chemotherapy.
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39
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Shivange G, Monisha M, Nigam R, Kodipelli N, Anindya R. RecA stimulates AlkB-mediated direct repair of DNA adducts. Nucleic Acids Res 2016; 44:8754-8763. [PMID: 27378775 PMCID: PMC5062977 DOI: 10.1093/nar/gkw611] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Accepted: 06/28/2016] [Indexed: 11/16/2022] Open
Abstract
The Escherichia coli AlkB protein is a 2-oxoglutarate/Fe(II)-dependent demethylase that repairs alkylated single stranded and double stranded DNA. Immunoaffinity chromatography coupled with mass spectrometry identified RecA, a key factor in homologous recombination, as an AlkB-associated protein. The interaction between AlkB and RecA was validated by yeast two-hybrid assay; size-exclusion chromatography and standard pull down experiment and was shown to be direct and mediated by the N-terminal domain of RecA. RecA binding results AlkB–RecA heterodimer formation and RecA–AlkB repairs alkylated DNA with higher efficiency than AlkB alone.
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Affiliation(s)
- Gururaj Shivange
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, 502285 Hyderabad, Telangana, India
| | - Mohan Monisha
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, 502285 Hyderabad, Telangana, India
| | - Richa Nigam
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, 502285 Hyderabad, Telangana, India
| | - Naveena Kodipelli
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, 502285 Hyderabad, Telangana, India
| | - Roy Anindya
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, 502285 Hyderabad, Telangana, India
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40
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Patra A, Su Y, Zhang Q, Johnson KM, Guengerich FP, Egli M. Structural and Kinetic Analysis of Miscoding Opposite the DNA Adduct 1,N6-Ethenodeoxyadenosine by Human Translesion DNA Polymerase η. J Biol Chem 2016; 291:14134-14145. [PMID: 27226627 PMCID: PMC4933172 DOI: 10.1074/jbc.m116.732487] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 05/13/2016] [Indexed: 01/12/2023] Open
Abstract
1,N(6)-Ethenodeoxyadenosine (1,N(6)-ϵdA) is the major etheno lesion formed in the reaction of DNA with epoxides substituted with good leaving groups (e.g. vinyl chloride epoxide). This lesion is also formed endogenously in DNA from lipid oxidation. Recombinant human DNA polymerase η (hpol η) can replicate oligonucleotide templates containing 1,N(6)-ϵdA. In steady-state kinetic analysis, hpol η preferred to incorporate dATP and dGTP, compared with dTTP. Mass spectral analysis of incorporation products also showed preferred purine (A, G) incorporation and extensive -1 frameshifts, suggesting pairing of the inserted purine and slippage before further replication. Five x-ray crystal structures of hpol η ternary complexes were determined, three at the insertion and two at the extension stage. Two insertion complexes revealed incoming non-hydrolyzable dATP or dGTP analogs not pairing with but instead in a staggered configuration relative to 1,N(6)-ϵdA in the anti conformation, thus opposite the 5'-T in the template, explaining the proclivity for frameshift misincorporation. In another insertion complex, dTTP was positioned opposite 1,N(6)-ϵdA, and the adduct base was in the syn conformation, with formation of two hydrogen bonds. At the extension stage, with either an incorporated dA or dT opposite 1,N(6)-ϵdA and 2'-deoxythymidine-5'-[(α,β)-imido]triphosphate opposite the 5'-A, the 3'-terminal nucleoside of the primer was disordered, consistent with the tendency not to incorporate dTTP opposite 1,N(6)-ϵdA. Collectively, the results show a preference for purine pairing opposite 1,N(6)-ϵdA and for -1 frameshifts.
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Affiliation(s)
- Amritraj Patra
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - Yan Su
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - Qianqian Zhang
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - Kevin M Johnson
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146.
| | - Martin Egli
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146.
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41
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You C, Wang P, Nay SL, Wang J, Dai X, O’Connor TR, Wang Y. Roles of Aag, Alkbh2, and Alkbh3 in the Repair of Carboxymethylated and Ethylated Thymidine Lesions. ACS Chem Biol 2016; 11:1332-8. [PMID: 26930515 DOI: 10.1021/acschembio.6b00085] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Environmental and endogenous genotoxic agents can result in a variety of alkylated and carboxymethylated DNA lesions, including N3-ethylthymidine (N3-EtdT), O(2)-EtdT, and O(4)-EtdT as well as N3-carboxymethylthymidine (N3-CMdT) and O(4)-CMdT. By using nonreplicative double-stranded vectors harboring a site-specifically incorporated DNA lesion, we assessed the potential roles of alkyladenine DNA glycosylase (Aag); alkylation repair protein B homologue 2 (Alkbh2); or Alkbh3 in modulating the effects of N3-EtdT, O(2)-EtdT, O(4)-EtdT, N3-CMdT, or O(4)-CMdT on DNA transcription in mammalian cells. We found that the depletion of Aag did not significantly change the transcriptional inhibitory or mutagenic properties of all five examined lesions, suggesting a negligible role of Aag in the repair of these DNA adducts in mammalian cells. In addition, our results revealed that N3-EtdT, but not other lesions, could be repaired by Alkbh2 and Alkbh3 in mammalian cells. Furthermore, we demonstrated the direct reversal of N3-EtdT by purified human Alkbh2 protein in vitro. These findings provided important new insights into the repair of the carboxymethylated and alkylated thymidine lesions in mammalian cells.
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Affiliation(s)
- Changjun You
- Department
of Chemistry, University of California, Riverside, California, United States
| | - Pengcheng Wang
- Environmental
Toxicology Graduate Program, University of California, Riverside, California, United States
| | - Stephanie L. Nay
- Department
of Cancer Biology, Beckman Research Institute, Duarte, California, United States
| | - Jianshuang Wang
- Department
of Chemistry, University of California, Riverside, California, United States
| | - Xiaoxia Dai
- Department
of Chemistry, University of California, Riverside, California, United States
| | - Timothy R. O’Connor
- Department
of Cancer Biology, Beckman Research Institute, Duarte, California, United States
| | - Yinsheng Wang
- Department
of Chemistry, University of California, Riverside, California, United States
- Environmental
Toxicology Graduate Program, University of California, Riverside, California, United States
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42
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Yang T, Cheong A, Mai X, Zou S, Woon ECY. A methylation-switchable conformational probe for the sensitive and selective detection of RNA demethylase activity. Chem Commun (Camb) 2016; 52:6181-4. [PMID: 27074833 DOI: 10.1039/c6cc01045h] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We describe a novel methylation-sensitive nucleic acid (RNA) probe which switches conformation according to its methylation status. When combined with a differential scanning fluorimetry technique, it enables highly sensitive and selective detection of demethylase activity at a single methylated-base level. The approach is highly versatile and may be adapted to a broad range of RNA demethylases.
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Affiliation(s)
- Tianming Yang
- Department of Pharmacy, National University of Singapore, 18 Science Drive 4, 117 543, Singapore.
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43
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Chen F, Tang Q, Bian K, Humulock ZT, Yang X, Jost M, Drennan CL, Essigmann JM, Li D. Adaptive Response Enzyme AlkB Preferentially Repairs 1-Methylguanine and 3-Methylthymine Adducts in Double-Stranded DNA. Chem Res Toxicol 2016; 29:687-93. [PMID: 26919079 DOI: 10.1021/acs.chemrestox.5b00522] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The AlkB protein is a repair enzyme that uses an α-ketoglutarate/Fe(II)-dependent mechanism to repair alkyl DNA adducts. AlkB has been reported to repair highly susceptible substrates, such as 1-methyladenine and 3-methylcytosine, more efficiently in ss-DNA than in ds-DNA. Here, we tested the repair of weaker AlkB substrates 1-methylguanine and 3-methylthymine and found that AlkB prefers to repair them in ds-DNA. We also discovered that AlkB and its human homologues, ABH2 and ABH3, are able to repair the aforementioned adducts when the adduct is present in a mismatched base pair. These observations demonstrate the strong adaptability of AlkB toward repairing various adducts in different environments.
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Affiliation(s)
- Fangyi Chen
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Qi Tang
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Ke Bian
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Zachary T Humulock
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Xuedong Yang
- School of Pharmaceutical Science and Technology, Tianjin University , Tianjin 300072, P. R. China
| | | | | | | | - Deyu Li
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island , Kingston, Rhode Island 02881, United States
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44
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You C, Wang Y. Mass Spectrometry-Based Quantitative Strategies for Assessing the Biological Consequences and Repair of DNA Adducts. Acc Chem Res 2016; 49:205-13. [PMID: 26758048 DOI: 10.1021/acs.accounts.5b00437] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The genetic integrity of living organisms is constantly threatened by environmental and endogenous sources of DNA damaging agents that can induce a plethora of chemically modified DNA lesions. Unrepaired DNA lesions may elicit cytotoxic and mutagenic effects and contribute to the development of human diseases including cancer and neurodegeneration. Understanding the deleterious outcomes of DNA damage necessitates the investigation about the effects of DNA adducts on the efficiency and fidelity of DNA replication and transcription. Conventional methods for measuring lesion-induced replicative or transcriptional alterations often require time-consuming colony screening and DNA sequencing procedures. Recently, a series of mass spectrometry (MS)-based strategies have been developed in our laboratory as an efficient platform for qualitative and quantitative analyses of the changes in genetic information induced by DNA adducts during DNA replication and transcription. During the past few years, we have successfully used these MS-based methods for assessing the replicative or transcriptional blocking and miscoding properties of more than 30 distinct DNA adducts. When combined with genetic manipulation, these methods have also been successfully employed for revealing the roles of various DNA repair proteins or translesion synthesis DNA polymerases (Pols) in modulating the adverse effects of DNA lesions on transcription or replication in mammalian and bacterial cells. For instance, we found that Escherichia coli Pol IV and its mammalian ortholog (i.e., Pol κ) are required for error-free bypass of N(2)-(1-carboxyethyl)-2'-deoxyguanosine (N(2)-CEdG) in cells. We also found that the N(2)-CEdG lesions strongly inhibit DNA transcription and they are repaired by transcription-coupled nucleotide excision repair in mammalian cells. In this Account, we focus on the development of MS-based approaches for determining the effects of DNA adducts on DNA replication and transcription, where liquid chromatography-tandem mass spectrometry is employed for the identification, and sometimes quantification, of the progeny products arising from the replication or transcription of lesion-bearing DNA substrates in vitro and in mammalian cells. We also highlight their applications to lesion bypass, mutagenesis, and repair studies of three representative types of DNA lesions, that is, the methylglyoxal-induced N(2)-CEdG, oxidatively induced 8,5'-cyclopurine-2'-deoxynucleosides, and regioisomeric alkylated thymidine lesions. Specially, we discuss the similar and distinct effects of the minor-groove DNA lesions including N(2)-CEdG and O(2)-alkylated thymidine lesions, as well as the major-groove O(4)-alkylated thymidine lesions on DNA replication and transcription machinery. For example, we found that the addition of an alkyl group to the O(4) position of thymine may facilitate its preferential pairing with guanine and thus induce exclusively the misincorporation of guanine nucleotide opposite the lesion, whereas alkylation of thymine at the O(2) position may render the nucleobase unfavorable in pairing with any of the canonical nucleobases and thus exhibit promiscuous miscoding properties during DNA replication and transcription. The MS-based strategies described herein should be generally applicable for quantitative measurement of the biological consequences and repair of other DNA lesions in vitro and in cells.
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Affiliation(s)
- Changjun You
- Department
of Chemistry, University of California, Riverside, California 92521-0403, United States
| | - Yinsheng Wang
- Department
of Chemistry, University of California, Riverside, California 92521-0403, United States
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45
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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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46
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Yu Y, Guerrero CR, Liu S, Amato NJ, Sharma Y, Gupta S, Wang Y. Comprehensive Assessment of Oxidatively Induced Modifications of DNA in a Rat Model of Human Wilson's Disease. Mol Cell Proteomics 2015; 15:810-7. [PMID: 26362317 DOI: 10.1074/mcp.m115.052696] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Indexed: 01/14/2023] Open
Abstract
Defective copper excretion from hepatocytes in Wilson's disease causes accumulation of copper ions with increased generation of reactive oxygen species via the Fenton-type reaction. Here we developed a nanoflow liquid chromatography-nanoelectrospray ionization-tandem mass spectrometry coupled with the isotope-dilution method for the simultaneous quantification of oxidatively induced DNA modifications. This method enabled measurement, in microgram quantities of DNA, of four oxidative stress-induced lesions, including direct ROS-induced purine cyclonucleosides (cPus) and two exocyclic adducts induced by byproducts of lipid peroxidation, i.e. 1,N(6)-etheno-2'-deoxyadenosine (εdA) and 1,N(2)-etheno-2'-deoxyguanosine (εdG). Analysis of liver tissues of Long-Evans Cinnamon rats, which constitute an animal model of human Wilson's disease, and their healthy counterparts [i.e. Long-Evans Agouti rats] showed significantly higher levels of all four DNA lesions in Long-Evans Cinnamon than Long-Evans Agouti rats. Moreover, cPus were present at much higher levels than εdA and εdG lesions. In contrast, the level of 5-hydroxymethyl-2'-deoxycytidine (5-HmdC), an oxidation product of 5-methyl-2'-deoxycytidine (5-mdC), was markedly lower in the liver tissues of Long-Evans Cinnamon than Long-Evans Agouti rats, though no differences were observed for the levels of 5-mdC. In vitro biochemical assay showed that Cu(2+) ions could directly inhibit the activity of Tet enzymes. Together, these results suggest that aberrant copper accumulation may perturb genomic stability by elevating oxidatively induced DNA lesions, and by altering epigenetic pathways of gene regulation.
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Affiliation(s)
- Yang Yu
- From the ‡Environmental Toxicology Graduate Program and
| | - Candace R Guerrero
- §Department of Chemistry, University of California, Riverside, California 92521
| | - Shuo Liu
- From the ‡Environmental Toxicology Graduate Program and
| | - Nicholas J Amato
- §Department of Chemistry, University of California, Riverside, California 92521
| | | | - Sanjeev Gupta
- ¶Department of Medicine and ‖Department of Pathology, **Marion Bessin Liver Research Center, Diabetes Center, Cancer Center, and Ruth L. and David S. Gottesman Institute for Stem Cell and Regenerative Medicine Research, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Yinsheng Wang
- From the ‡Environmental Toxicology Graduate Program and §Department of Chemistry, University of California, Riverside, California 92521;
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47
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Kim I, Choi JS, Lee S, Byeon HJ, Lee ES, Shin BS, Choi HG, Lee KC, Youn YS. In situ facile-forming PEG cross-linked albumin hydrogels loaded with an apoptotic TRAIL protein. J Control Release 2015; 214:30-9. [PMID: 26188152 DOI: 10.1016/j.jconrel.2015.07.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 06/08/2015] [Accepted: 07/11/2015] [Indexed: 01/01/2023]
Abstract
The key to making a practicable hydrogel for pharmaceutical or medical purposes is to endow it with relevant properties, i.e., facile fabrication, gelation time-controllability, and in situ injectability given a firm basis for safety/biocompatibility. Here, the authors describe an in situ gelling, injectable, albumin-cross-linked polyethylene glycol (PEG) hydrogel that was produced using a thiol-maleimide reaction. This hydrogel consists of two biocompatible components, namely, thiolated human serum albumin and 4-arm PEG20k-maleimide, and can be easily fabricated and gelled in situ within 60s by simply mixing its two components. In addition, the gelation time of this system is controllable in the range 15s to 5min. This hydrogel hardly interacted with an apoptotic TRAIL protein, ensuring suitable release profiles that maximize therapeutic efficacy. Specifically, tumors (volume: 278.8mm(3)) in Mia Paca-2 cell-xenografted BALB/c nu/nu mice treated with the TRAIL-loaded HSA-PEG hydrogel were markedly smaller than mice treated with the hydrogel prepared via an amine-N-hydroxysuccinimide reaction or non-treated mice (1275.5mm(3) and 1816.5mm(3), respectively). We believe that this hydrogel would be a new prototype of locally injectable sustained-release type anti-cancer agents, and furthermore offers practical convenience for a doctor and universal applicability for a variety of therapeutic proteins.
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Affiliation(s)
- Insoo Kim
- School of Pharmacy, Sungkyunkwan University, 300 Cheoncheon-dong, Jangan-gu, Suwon, Gyeonggi-do 440-746, Republic of Korea
| | - Ji Su Choi
- School of Pharmacy, Sungkyunkwan University, 300 Cheoncheon-dong, Jangan-gu, Suwon, Gyeonggi-do 440-746, Republic of Korea
| | - Seunghyun Lee
- School of Pharmacy, Sungkyunkwan University, 300 Cheoncheon-dong, Jangan-gu, Suwon, Gyeonggi-do 440-746, Republic of Korea
| | - Hyeong Jun Byeon
- School of Pharmacy, Sungkyunkwan University, 300 Cheoncheon-dong, Jangan-gu, Suwon, Gyeonggi-do 440-746, Republic of Korea
| | - Eun Seong Lee
- Division of Biotechnology, The Catholic University of Korea, 43-1 Yeokgok 2-dong, Wonmi-gu, Bucheon-si, Gyeonggi-do 420-743, Republic of Korea
| | - Beom Soo Shin
- College of Pharmacy, Catholic University of Daegu, 330 Geumrak 1-ri, Hayang Eup, Gyeongsan si, Gyeongbuk 712-702, Republic of Korea
| | - Han-Gon Choi
- College of Pharmacy & Institute of Pharmaceutical Science and Technology, Hanyang University, 55, Hanyangdaehak-ro, Sangnok-gu, Ansan, Gyeonggi-do 426-791, Republic of Korea
| | - Kang Choon Lee
- School of Pharmacy, Sungkyunkwan University, 300 Cheoncheon-dong, Jangan-gu, Suwon, Gyeonggi-do 440-746, Republic of Korea
| | - Yu Seok Youn
- School of Pharmacy, Sungkyunkwan University, 300 Cheoncheon-dong, Jangan-gu, Suwon, Gyeonggi-do 440-746, Republic of Korea.
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48
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Fedeles BI, Singh V, Delaney JC, Li D, Essigmann JM. The AlkB Family of Fe(II)/α-Ketoglutarate-dependent Dioxygenases: Repairing Nucleic Acid Alkylation Damage and Beyond. J Biol Chem 2015; 290:20734-20742. [PMID: 26152727 DOI: 10.1074/jbc.r115.656462] [Citation(s) in RCA: 270] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The AlkB family of Fe(II)- and α-ketoglutarate-dependent dioxygenases is a class of ubiquitous direct reversal DNA repair enzymes that remove alkyl adducts from nucleobases by oxidative dealkylation. The prototypical and homonymous family member is an Escherichia coli "adaptive response" protein that protects the bacterial genome against alkylation damage. AlkB has a wide variety of substrates, including monoalkyl and exocyclic bridged adducts. Nine mammalian AlkB homologs exist (ALKBH1-8, FTO), but only a subset functions as DNA/RNA repair enzymes. This minireview presents an overview of the AlkB proteins including recent data on homologs, structural features, substrate specificities, and experimental strategies for studying DNA repair by AlkB family proteins.
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Affiliation(s)
- Bogdan I Fedeles
- Departments of Chemistry and Biological Engineering and the Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Vipender Singh
- Departments of Chemistry and Biological Engineering and the Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - James C Delaney
- Departments of Chemistry and Biological Engineering and the Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Deyu Li
- Departments of Chemistry and Biological Engineering and the Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139.
| | - John M Essigmann
- Departments of Chemistry and Biological Engineering and the Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139.
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49
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Sikora A, Maciejewska AM, Poznański J, Pilżys T, Marcinkowski M, Dylewska M, Piwowarski J, Jakubczak W, Pawlak K, Grzesiuk E. Effects of changes in intracellular iron pool on AlkB-dependent and AlkB-independent mechanisms protecting E.coli cells against mutagenic action of alkylating agent. Mutat Res 2015; 778:52-60. [PMID: 26114961 DOI: 10.1016/j.mrfmmm.2015.05.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 04/30/2015] [Accepted: 05/21/2015] [Indexed: 11/29/2022]
Abstract
An Escherichia coli hemH mutant accumulates protoporphyrin IX, causing photosensitivity of cells to visible light. Here, we have shown that intracellular free iron in hemH mutants is double that observed in hemH(+) strain. The aim of this study was to recognize the influence of this increased free iron concentration on AlkB-directed repair of alkylated DNA by analyzing survival and argE3 → Arg(+) reversion induction after λ>320 nm light irradiation and MMS-treatment in E. coli AB1157 hemH and alkB mutants. E.coli AlkB dioxygenase constitutes a direct single-protein repair system using non-hem Fe(II) and cofactors 2-oxoglutarate (2OG) and oxygen (O2) to initiate oxidative dealkylation of DNA/RNA bases. We have established that the frequency of MMS-induced Arg(+) revertants in AB1157 alkB(+)hemH(-)/pMW1 strain was 40 and 26% reduced comparing to the alkB(+)hemH(-) and alkB(+)hemH(+)/pMW1, respectively. It is noteworthy that the effect was observed only when bacteria were irradiated with λ>320 nm light prior MMS-treatment. This finding indicates efficient repair of alkylated DNA in photosensibilized cells in the presence of higher free iron pool and AlkB concentrations. Interestingly, a 31% decrease in the level of Arg(+) reversion was observed in irradiated and MMS-treated hemH(-)alkB(-) cells comparing to the hemH(+)alkB(-) strain. Also, the level of Arg(+) revertants in the irradiated and MMS treated hemH(-) alkB(-) mutant was significantly lower (by 34%) in comparison to the same strain but MMS-treated only. These indicate AlkB-independent repair involving Fe ions and reactive oxygen species. According to our hypothesis it may be caused by non-enzymatic dealkylation of alkylated dNTPs in E. coli cells. In in vitro studies, the absence of AlkB protein in the presence of iron ions allowed etheno(ϵ) dATP and ϵdCTP to spontaneously convert to dAMP and dCMP, respectively. Thus, hemH(-) intra-cellular conditions may favor Fe-dependent dealkylation of modified dNTPs.
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Affiliation(s)
- Anna Sikora
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | | | - Jarosław Poznański
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Tomasz Pilżys
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Michał Marcinkowski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Małgorzata Dylewska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Jan Piwowarski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Wioletta Jakubczak
- Department of Analytical Chemistry, Faculty of Chemistry, Warsaw University of Technology, Warsaw, Poland
| | - Katarzyna Pawlak
- Department of Analytical Chemistry, Faculty of Chemistry, Warsaw University of Technology, Warsaw, Poland
| | - Elżbieta Grzesiuk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.
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Chang SC, Fedeles BI, Wu J, Delaney JC, Li D, Zhao L, Christov PP, Yau E, Singh V, Jost M, Drennan CL, Marnett LJ, Rizzo CJ, Levine SS, Guengerich FP, Essigmann JM. Next-generation sequencing reveals the biological significance of the N(2),3-ethenoguanine lesion in vivo. Nucleic Acids Res 2015; 43:5489-500. [PMID: 25837992 PMCID: PMC4477646 DOI: 10.1093/nar/gkv243] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Revised: 03/06/2015] [Accepted: 03/09/2015] [Indexed: 12/20/2022] Open
Abstract
Etheno DNA adducts are a prevalent type of DNA damage caused by vinyl chloride (VC) exposure and oxidative stress. Etheno adducts are mutagenic and may contribute to the initiation of several pathologies; thus, elucidating the pathways by which they induce cellular transformation is critical. Although N(2),3-ethenoguanine (N(2),3-εG) is the most abundant etheno adduct, its biological consequences have not been well characterized in cells due to its labile glycosidic bond. Here, a stabilized 2'-fluoro-2'-deoxyribose analog of N(2),3-εG was used to quantify directly its genotoxicity and mutagenicity. A multiplex method involving next-generation sequencing enabled a large-scale in vivo analysis, in which both N(2),3-εG and its isomer 1,N(2)-ethenoguanine (1,N(2)-εG) were evaluated in various repair and replication backgrounds. We found that N(2),3-εG potently induces G to A transitions, the same mutation previously observed in VC-associated tumors. By contrast, 1,N(2)-εG induces various substitutions and frameshifts. We also found that N(2),3-εG is the only etheno lesion that cannot be repaired by AlkB, which partially explains its persistence. Both εG lesions are strong replication blocks and DinB, a translesion polymerase, facilitates the mutagenic bypass of both lesions. Collectively, our results indicate that N(2),3-εG is a biologically important lesion and may have a functional role in VC-induced or inflammation-driven carcinogenesis.
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Affiliation(s)
- Shiou-chi Chang
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Bogdan I Fedeles
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Jie Wu
- BioMicro Center, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - James C Delaney
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Deyu Li
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Linlin Zhao
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, United States Center in Molecular Toxicology, Vanderbilt University, Nashville, TN 37232, United States
| | - Plamen P Christov
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, United States Center in Molecular Toxicology, Vanderbilt University, Nashville, TN 37232, United States Department of Chemistry, Vanderbilt University, Nashville, TN 37232, United States
| | - Emily Yau
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Vipender Singh
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Marco Jost
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Catherine L Drennan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Lawrence J Marnett
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, United States Center in Molecular Toxicology, Vanderbilt University, Nashville, TN 37232, United States Department of Chemistry, Vanderbilt University, Nashville, TN 37232, United States Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN 37232, United States
| | - Carmelo J Rizzo
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, United States Center in Molecular Toxicology, Vanderbilt University, Nashville, TN 37232, United States Department of Chemistry, Vanderbilt University, Nashville, TN 37232, United States Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN 37232, United States
| | - Stuart S Levine
- BioMicro Center, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - F Peter Guengerich
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, United States Center in Molecular Toxicology, Vanderbilt University, Nashville, TN 37232, United States Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN 37232, United States
| | - John M Essigmann
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
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